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/DeclVisitor.h"
17 #include "clang/AST/DeclCXX.h"
18 #include "clang/AST/DeclTemplate.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/AST/DeclContextInternals.h"
21 #include "clang/Basic/SourceManager.h"
22 #include "llvm/ADT/Twine.h"
23 #include "llvm/Bitcode/BitstreamWriter.h"
24 #include "llvm/Support/ErrorHandling.h"
25 using namespace clang;
26 using namespace serialization;
27 
28 //===----------------------------------------------------------------------===//
29 // Declaration serialization
30 //===----------------------------------------------------------------------===//
31 
32 namespace clang {
33   class ASTDeclWriter : public DeclVisitor<ASTDeclWriter, void> {
34 
35     ASTWriter &Writer;
36     ASTContext &Context;
37     typedef ASTWriter::RecordData RecordData;
38     RecordData &Record;
39 
40   public:
41     serialization::DeclCode Code;
42     unsigned AbbrevToUse;
43 
44     ASTDeclWriter(ASTWriter &Writer, ASTContext &Context, RecordData &Record)
45       : Writer(Writer), Context(Context), Record(Record) {
46     }
47 
48     void Visit(Decl *D);
49 
50     void VisitDecl(Decl *D);
51     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
52     void VisitNamedDecl(NamedDecl *D);
53     void VisitLabelDecl(LabelDecl *LD);
54     void VisitNamespaceDecl(NamespaceDecl *D);
55     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
56     void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
57     void VisitTypeDecl(TypeDecl *D);
58     void VisitTypedefNameDecl(TypedefNameDecl *D);
59     void VisitTypedefDecl(TypedefDecl *D);
60     void VisitTypeAliasDecl(TypeAliasDecl *D);
61     void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
62     void VisitTagDecl(TagDecl *D);
63     void VisitEnumDecl(EnumDecl *D);
64     void VisitRecordDecl(RecordDecl *D);
65     void VisitCXXRecordDecl(CXXRecordDecl *D);
66     void VisitClassTemplateSpecializationDecl(
67                                             ClassTemplateSpecializationDecl *D);
68     void VisitClassTemplatePartialSpecializationDecl(
69                                      ClassTemplatePartialSpecializationDecl *D);
70     void VisitClassScopeFunctionSpecializationDecl(
71                                        ClassScopeFunctionSpecializationDecl *D);
72     void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
73     void VisitValueDecl(ValueDecl *D);
74     void VisitEnumConstantDecl(EnumConstantDecl *D);
75     void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
76     void VisitDeclaratorDecl(DeclaratorDecl *D);
77     void VisitFunctionDecl(FunctionDecl *D);
78     void VisitCXXMethodDecl(CXXMethodDecl *D);
79     void VisitCXXConstructorDecl(CXXConstructorDecl *D);
80     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
81     void VisitCXXConversionDecl(CXXConversionDecl *D);
82     void VisitFieldDecl(FieldDecl *D);
83     void VisitIndirectFieldDecl(IndirectFieldDecl *D);
84     void VisitVarDecl(VarDecl *D);
85     void VisitImplicitParamDecl(ImplicitParamDecl *D);
86     void VisitParmVarDecl(ParmVarDecl *D);
87     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
88     void VisitTemplateDecl(TemplateDecl *D);
89     void VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
90     void VisitClassTemplateDecl(ClassTemplateDecl *D);
91     void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
92     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
93     void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
94     void VisitUsingDecl(UsingDecl *D);
95     void VisitUsingShadowDecl(UsingShadowDecl *D);
96     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
97     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
98     void VisitImportDecl(ImportDecl *D);
99     void VisitAccessSpecDecl(AccessSpecDecl *D);
100     void VisitFriendDecl(FriendDecl *D);
101     void VisitFriendTemplateDecl(FriendTemplateDecl *D);
102     void VisitStaticAssertDecl(StaticAssertDecl *D);
103     void VisitBlockDecl(BlockDecl *D);
104 
105     void VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
106                           uint64_t VisibleOffset);
107     template <typename T> void VisitRedeclarable(Redeclarable<T> *D);
108 
109 
110     // FIXME: Put in the same order is DeclNodes.td?
111     void VisitObjCMethodDecl(ObjCMethodDecl *D);
112     void VisitObjCContainerDecl(ObjCContainerDecl *D);
113     void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
114     void VisitObjCIvarDecl(ObjCIvarDecl *D);
115     void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
116     void VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D);
117     void VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *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->TopLevelDeclInObjCContainer);
159   Record.push_back(D->getAccess());
160   Record.push_back(D->ModulePrivate);
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->getPreviousDeclaration() &&
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   Writer.AddDeclRef(D->getInstantiatedFromMemberEnum(), Record);
235 
236   if (!D->hasAttrs() &&
237       !D->isImplicit() &&
238       !D->isUsed(false) &&
239       !D->hasExtInfo() &&
240       !D->getPreviousDeclaration() &&
241       !D->isInvalidDecl() &&
242       !D->isReferenced() &&
243       !D->isTopLevelDeclInObjCContainer() &&
244       D->getAccess() == AS_none &&
245       !D->isModulePrivate() &&
246       !CXXRecordDecl::classofKind(D->getKind()) &&
247       !D->getIntegerTypeSourceInfo() &&
248       D->getDeclName().getNameKind() == DeclarationName::Identifier)
249     AbbrevToUse = Writer.getDeclEnumAbbrev();
250 
251   Code = serialization::DECL_ENUM;
252 }
253 
254 void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
255   VisitTagDecl(D);
256   Record.push_back(D->hasFlexibleArrayMember());
257   Record.push_back(D->isAnonymousStructOrUnion());
258   Record.push_back(D->hasObjectMember());
259 
260   if (!D->hasAttrs() &&
261       !D->isImplicit() &&
262       !D->isUsed(false) &&
263       !D->hasExtInfo() &&
264       !D->getPreviousDeclaration() &&
265       !D->isInvalidDecl() &&
266       !D->isReferenced() &&
267       !D->isTopLevelDeclInObjCContainer() &&
268       D->getAccess() == AS_none &&
269       !D->isModulePrivate() &&
270       !CXXRecordDecl::classofKind(D->getKind()) &&
271       D->getDeclName().getNameKind() == DeclarationName::Identifier)
272     AbbrevToUse = Writer.getDeclRecordAbbrev();
273 
274   Code = serialization::DECL_RECORD;
275 }
276 
277 void ASTDeclWriter::VisitValueDecl(ValueDecl *D) {
278   VisitNamedDecl(D);
279   Writer.AddTypeRef(D->getType(), Record);
280 }
281 
282 void ASTDeclWriter::VisitEnumConstantDecl(EnumConstantDecl *D) {
283   VisitValueDecl(D);
284   Record.push_back(D->getInitExpr()? 1 : 0);
285   if (D->getInitExpr())
286     Writer.AddStmt(D->getInitExpr());
287   Writer.AddAPSInt(D->getInitVal(), Record);
288 
289   Code = serialization::DECL_ENUM_CONSTANT;
290 }
291 
292 void ASTDeclWriter::VisitDeclaratorDecl(DeclaratorDecl *D) {
293   VisitValueDecl(D);
294   Writer.AddSourceLocation(D->getInnerLocStart(), Record);
295   Record.push_back(D->hasExtInfo());
296   if (D->hasExtInfo())
297     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
298 }
299 
300 void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
301   VisitRedeclarable(D);
302   VisitDeclaratorDecl(D);
303 
304   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
305   Record.push_back(D->getIdentifierNamespace());
306   Record.push_back(D->getTemplatedKind());
307   switch (D->getTemplatedKind()) {
308   default: llvm_unreachable("Unhandled TemplatedKind!");
309   case FunctionDecl::TK_NonTemplate:
310     break;
311   case FunctionDecl::TK_FunctionTemplate:
312     Writer.AddDeclRef(D->getDescribedFunctionTemplate(), Record);
313     break;
314   case FunctionDecl::TK_MemberSpecialization: {
315     MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo();
316     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
317     Record.push_back(MemberInfo->getTemplateSpecializationKind());
318     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
319     break;
320   }
321   case FunctionDecl::TK_FunctionTemplateSpecialization: {
322     FunctionTemplateSpecializationInfo *
323       FTSInfo = D->getTemplateSpecializationInfo();
324     Writer.AddDeclRef(FTSInfo->getTemplate(), Record);
325     Record.push_back(FTSInfo->getTemplateSpecializationKind());
326 
327     // Template arguments.
328     Writer.AddTemplateArgumentList(FTSInfo->TemplateArguments, Record);
329 
330     // Template args as written.
331     Record.push_back(FTSInfo->TemplateArgumentsAsWritten != 0);
332     if (FTSInfo->TemplateArgumentsAsWritten) {
333       Record.push_back(FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs);
334       for (int i=0, e = FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs;
335              i!=e; ++i)
336         Writer.AddTemplateArgumentLoc((*FTSInfo->TemplateArgumentsAsWritten)[i],
337                                       Record);
338       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->LAngleLoc,
339                                Record);
340       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->RAngleLoc,
341                                Record);
342     }
343 
344     Writer.AddSourceLocation(FTSInfo->getPointOfInstantiation(), Record);
345 
346     if (D->isCanonicalDecl()) {
347       // Write the template that contains the specializations set. We will
348       // add a FunctionTemplateSpecializationInfo to it when reading.
349       Writer.AddDeclRef(FTSInfo->getTemplate()->getCanonicalDecl(), Record);
350     }
351     break;
352   }
353   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
354     DependentFunctionTemplateSpecializationInfo *
355       DFTSInfo = D->getDependentSpecializationInfo();
356 
357     // Templates.
358     Record.push_back(DFTSInfo->getNumTemplates());
359     for (int i=0, e = DFTSInfo->getNumTemplates(); i != e; ++i)
360       Writer.AddDeclRef(DFTSInfo->getTemplate(i), Record);
361 
362     // Templates args.
363     Record.push_back(DFTSInfo->getNumTemplateArgs());
364     for (int i=0, e = DFTSInfo->getNumTemplateArgs(); i != e; ++i)
365       Writer.AddTemplateArgumentLoc(DFTSInfo->getTemplateArg(i), Record);
366     Writer.AddSourceLocation(DFTSInfo->getLAngleLoc(), Record);
367     Writer.AddSourceLocation(DFTSInfo->getRAngleLoc(), Record);
368     break;
369   }
370   }
371 
372   // FunctionDecl's body is handled last at ASTWriterDecl::Visit,
373   // after everything else is written.
374 
375   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
376   Record.push_back(D->getStorageClassAsWritten());
377   Record.push_back(D->IsInline);
378   Record.push_back(D->isInlineSpecified());
379   Record.push_back(D->isVirtualAsWritten());
380   Record.push_back(D->isPure());
381   Record.push_back(D->hasInheritedPrototype());
382   Record.push_back(D->hasWrittenPrototype());
383   Record.push_back(D->isDeletedAsWritten());
384   Record.push_back(D->isTrivial());
385   Record.push_back(D->isDefaulted());
386   Record.push_back(D->isExplicitlyDefaulted());
387   Record.push_back(D->hasImplicitReturnZero());
388   Record.push_back(D->isConstexpr());
389   Writer.AddSourceLocation(D->getLocEnd(), Record);
390 
391   Record.push_back(D->param_size());
392   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
393        P != PEnd; ++P)
394     Writer.AddDeclRef(*P, Record);
395   Code = serialization::DECL_FUNCTION;
396 }
397 
398 void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
399   VisitNamedDecl(D);
400   // FIXME: convert to LazyStmtPtr?
401   // Unlike C/C++, method bodies will never be in header files.
402   bool HasBodyStuff = D->getBody() != 0     ||
403                       D->getSelfDecl() != 0 || D->getCmdDecl() != 0;
404   Record.push_back(HasBodyStuff);
405   if (HasBodyStuff) {
406     Writer.AddStmt(D->getBody());
407     Writer.AddDeclRef(D->getSelfDecl(), Record);
408     Writer.AddDeclRef(D->getCmdDecl(), Record);
409   }
410   Record.push_back(D->isInstanceMethod());
411   Record.push_back(D->isVariadic());
412   Record.push_back(D->isSynthesized());
413   Record.push_back(D->isDefined());
414 
415   Record.push_back(D->IsRedeclaration);
416   Record.push_back(D->HasRedeclaration);
417   if (D->HasRedeclaration) {
418     assert(Context.getObjCMethodRedeclaration(D));
419     Writer.AddDeclRef(Context.getObjCMethodRedeclaration(D), Record);
420   }
421 
422   // FIXME: stable encoding for @required/@optional
423   Record.push_back(D->getImplementationControl());
424   // FIXME: stable encoding for in/out/inout/bycopy/byref/oneway
425   Record.push_back(D->getObjCDeclQualifier());
426   Record.push_back(D->hasRelatedResultType());
427   Writer.AddTypeRef(D->getResultType(), Record);
428   Writer.AddTypeSourceInfo(D->getResultTypeSourceInfo(), Record);
429   Writer.AddSourceLocation(D->getLocEnd(), Record);
430   Record.push_back(D->param_size());
431   for (ObjCMethodDecl::param_iterator P = D->param_begin(),
432                                    PEnd = D->param_end(); P != PEnd; ++P)
433     Writer.AddDeclRef(*P, Record);
434 
435   Record.push_back(D->SelLocsKind);
436   unsigned NumStoredSelLocs = D->getNumStoredSelLocs();
437   SourceLocation *SelLocs = D->getStoredSelLocs();
438   Record.push_back(NumStoredSelLocs);
439   for (unsigned i = 0; i != NumStoredSelLocs; ++i)
440     Writer.AddSourceLocation(SelLocs[i], Record);
441 
442   Code = serialization::DECL_OBJC_METHOD;
443 }
444 
445 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
446   VisitNamedDecl(D);
447   Writer.AddSourceLocation(D->getAtStartLoc(), Record);
448   Writer.AddSourceRange(D->getAtEndRange(), Record);
449   // Abstract class (no need to define a stable serialization::DECL code).
450 }
451 
452 void ASTDeclWriter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
453   VisitRedeclarable(D);
454   VisitObjCContainerDecl(D);
455   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
456 
457   ObjCInterfaceDecl *Def = D->getDefinition();
458   Writer.AddDeclRef(Def, Record);
459 
460   if (D == Def) {
461     // Write the DefinitionData
462     ObjCInterfaceDecl::DefinitionData &Data = D->data();
463 
464     Writer.AddDeclRef(D->getSuperClass(), Record);
465     Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
466     Writer.AddSourceLocation(D->getEndOfDefinitionLoc(), Record);
467 
468     // Write out the protocols that are directly referenced by the @interface.
469     Record.push_back(Data.ReferencedProtocols.size());
470     for (ObjCInterfaceDecl::protocol_iterator P = D->protocol_begin(),
471                                            PEnd = D->protocol_end();
472          P != PEnd; ++P)
473       Writer.AddDeclRef(*P, Record);
474     for (ObjCInterfaceDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
475          PLEnd = D->protocol_loc_end();
476          PL != PLEnd; ++PL)
477       Writer.AddSourceLocation(*PL, Record);
478 
479     // Write out the protocols that are transitively referenced.
480     Record.push_back(Data.AllReferencedProtocols.size());
481     for (ObjCList<ObjCProtocolDecl>::iterator
482               P = Data.AllReferencedProtocols.begin(),
483            PEnd = Data.AllReferencedProtocols.end();
484          P != PEnd; ++P)
485       Writer.AddDeclRef(*P, Record);
486 
487     // Write out the ivars.
488     Record.push_back(D->ivar_size());
489     for (ObjCInterfaceDecl::ivar_iterator I = D->ivar_begin(),
490                                        IEnd = D->ivar_end(); I != IEnd; ++I)
491       Writer.AddDeclRef(*I, Record);
492 
493     Writer.AddDeclRef(D->getCategoryList(), Record);
494   }
495 
496   Code = serialization::DECL_OBJC_INTERFACE;
497 }
498 
499 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
500   VisitFieldDecl(D);
501   // FIXME: stable encoding for @public/@private/@protected/@package
502   Record.push_back(D->getAccessControl());
503   Record.push_back(D->getSynthesize());
504 
505   if (!D->hasAttrs() &&
506       !D->isImplicit() &&
507       !D->isUsed(false) &&
508       !D->isInvalidDecl() &&
509       !D->isReferenced() &&
510       !D->isModulePrivate() &&
511       !D->getBitWidth() &&
512       !D->hasExtInfo() &&
513       D->getDeclName())
514     AbbrevToUse = Writer.getDeclObjCIvarAbbrev();
515 
516   Code = serialization::DECL_OBJC_IVAR;
517 }
518 
519 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
520   VisitObjCContainerDecl(D);
521   Record.push_back(D->isInitiallyForwardDecl());
522   Record.push_back(D->isForwardDecl());
523   Writer.AddSourceLocation(D->getLocEnd(), Record);
524   Record.push_back(D->protocol_size());
525   for (ObjCProtocolDecl::protocol_iterator
526        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
527     Writer.AddDeclRef(*I, Record);
528   for (ObjCProtocolDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
529          PLEnd = D->protocol_loc_end();
530        PL != PLEnd; ++PL)
531     Writer.AddSourceLocation(*PL, Record);
532   Code = serialization::DECL_OBJC_PROTOCOL;
533 }
534 
535 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
536   VisitFieldDecl(D);
537   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
538 }
539 
540 void ASTDeclWriter::VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *D) {
541   VisitDecl(D);
542   Record.push_back(D->protocol_size());
543   for (ObjCForwardProtocolDecl::protocol_iterator
544        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
545     Writer.AddDeclRef(*I, Record);
546   for (ObjCForwardProtocolDecl::protocol_loc_iterator
547          PL = D->protocol_loc_begin(), PLEnd = D->protocol_loc_end();
548        PL != PLEnd; ++PL)
549     Writer.AddSourceLocation(*PL, Record);
550   Code = serialization::DECL_OBJC_FORWARD_PROTOCOL;
551 }
552 
553 void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
554   VisitObjCContainerDecl(D);
555   Writer.AddDeclRef(D->getClassInterface(), Record);
556   Record.push_back(D->protocol_size());
557   for (ObjCCategoryDecl::protocol_iterator
558        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
559     Writer.AddDeclRef(*I, Record);
560   for (ObjCCategoryDecl::protocol_loc_iterator
561          PL = D->protocol_loc_begin(), PLEnd = D->protocol_loc_end();
562        PL != PLEnd; ++PL)
563     Writer.AddSourceLocation(*PL, Record);
564   Writer.AddDeclRef(D->getNextClassCategory(), Record);
565   Record.push_back(D->hasSynthBitfield());
566   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
567   Code = serialization::DECL_OBJC_CATEGORY;
568 }
569 
570 void ASTDeclWriter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D) {
571   VisitNamedDecl(D);
572   Writer.AddDeclRef(D->getClassInterface(), Record);
573   Code = serialization::DECL_OBJC_COMPATIBLE_ALIAS;
574 }
575 
576 void ASTDeclWriter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
577   VisitNamedDecl(D);
578   Writer.AddSourceLocation(D->getAtLoc(), 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.AddCXXCtorInitializers(D->IvarInitializers, D->NumIvarInitializers,
610                                 Record);
611   Record.push_back(D->hasSynthBitfield());
612   Code = serialization::DECL_OBJC_IMPLEMENTATION;
613 }
614 
615 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
616   VisitDecl(D);
617   Writer.AddSourceLocation(D->getLocStart(), Record);
618   Writer.AddDeclRef(D->getPropertyDecl(), Record);
619   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
620   Writer.AddSourceLocation(D->getPropertyIvarDeclLoc(), Record);
621   Writer.AddStmt(D->getGetterCXXConstructor());
622   Writer.AddStmt(D->getSetterCXXAssignment());
623   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
624 }
625 
626 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
627   VisitDeclaratorDecl(D);
628   Record.push_back(D->isMutable());
629   Record.push_back(D->getBitWidth()? 1 : D->hasInClassInitializer() ? 2 : 0);
630   if (D->getBitWidth())
631     Writer.AddStmt(D->getBitWidth());
632   else if (D->hasInClassInitializer())
633     Writer.AddStmt(D->getInClassInitializer());
634   if (!D->getDeclName())
635     Writer.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D), Record);
636 
637   if (!D->hasAttrs() &&
638       !D->isImplicit() &&
639       !D->isUsed(false) &&
640       !D->isInvalidDecl() &&
641       !D->isReferenced() &&
642       !D->isTopLevelDeclInObjCContainer() &&
643       !D->isModulePrivate() &&
644       !D->getBitWidth() &&
645       !D->hasInClassInitializer() &&
646       !D->hasExtInfo() &&
647       !ObjCIvarDecl::classofKind(D->getKind()) &&
648       !ObjCAtDefsFieldDecl::classofKind(D->getKind()) &&
649       D->getDeclName())
650     AbbrevToUse = Writer.getDeclFieldAbbrev();
651 
652   Code = serialization::DECL_FIELD;
653 }
654 
655 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
656   VisitValueDecl(D);
657   Record.push_back(D->getChainingSize());
658 
659   for (IndirectFieldDecl::chain_iterator
660        P = D->chain_begin(),
661        PEnd = D->chain_end(); P != PEnd; ++P)
662     Writer.AddDeclRef(*P, Record);
663   Code = serialization::DECL_INDIRECTFIELD;
664 }
665 
666 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
667   VisitRedeclarable(D);
668   VisitDeclaratorDecl(D);
669   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
670   Record.push_back(D->getStorageClassAsWritten());
671   Record.push_back(D->isThreadSpecified());
672   Record.push_back(D->hasCXXDirectInitializer());
673   Record.push_back(D->isExceptionVariable());
674   Record.push_back(D->isNRVOVariable());
675   Record.push_back(D->isCXXForRangeDecl());
676   Record.push_back(D->isARCPseudoStrong());
677   if (D->getInit()) {
678     Record.push_back(!D->isInitKnownICE() ? 1 : (D->isInitICE() ? 3 : 2));
679     Writer.AddStmt(D->getInit());
680   } else {
681     Record.push_back(0);
682   }
683 
684   MemberSpecializationInfo *SpecInfo
685     = D->isStaticDataMember() ? D->getMemberSpecializationInfo() : 0;
686   Record.push_back(SpecInfo != 0);
687   if (SpecInfo) {
688     Writer.AddDeclRef(SpecInfo->getInstantiatedFrom(), Record);
689     Record.push_back(SpecInfo->getTemplateSpecializationKind());
690     Writer.AddSourceLocation(SpecInfo->getPointOfInstantiation(), Record);
691   }
692 
693   if (!D->hasAttrs() &&
694       !D->isImplicit() &&
695       !D->isUsed(false) &&
696       !D->isInvalidDecl() &&
697       !D->isReferenced() &&
698       !D->isTopLevelDeclInObjCContainer() &&
699       D->getAccess() == AS_none &&
700       !D->isModulePrivate() &&
701       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
702       !D->hasExtInfo() &&
703       !D->getPreviousDeclaration() &&
704       !D->hasCXXDirectInitializer() &&
705       D->getInit() == 0 &&
706       !isa<ParmVarDecl>(D) &&
707       !SpecInfo)
708     AbbrevToUse = Writer.getDeclVarAbbrev();
709 
710   Code = serialization::DECL_VAR;
711 }
712 
713 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
714   VisitVarDecl(D);
715   Code = serialization::DECL_IMPLICIT_PARAM;
716 }
717 
718 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
719   VisitVarDecl(D);
720   Record.push_back(D->isObjCMethodParameter());
721   Record.push_back(D->getFunctionScopeDepth());
722   Record.push_back(D->getFunctionScopeIndex());
723   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
724   Record.push_back(D->isKNRPromoted());
725   Record.push_back(D->hasInheritedDefaultArg());
726   Record.push_back(D->hasUninstantiatedDefaultArg());
727   if (D->hasUninstantiatedDefaultArg())
728     Writer.AddStmt(D->getUninstantiatedDefaultArg());
729   Code = serialization::DECL_PARM_VAR;
730 
731   assert(!D->isARCPseudoStrong()); // can be true of ImplicitParamDecl
732 
733   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
734   // we dynamically check for the properties that we optimize for, but don't
735   // know are true of all PARM_VAR_DECLs.
736   if (!D->hasAttrs() &&
737       !D->hasExtInfo() &&
738       !D->isImplicit() &&
739       !D->isUsed(false) &&
740       D->getAccess() == AS_none &&
741       !D->isModulePrivate() &&
742       D->getStorageClass() == 0 &&
743       !D->hasCXXDirectInitializer() && // Can params have this ever?
744       D->getFunctionScopeDepth() == 0 &&
745       D->getObjCDeclQualifier() == 0 &&
746       !D->isKNRPromoted() &&
747       !D->hasInheritedDefaultArg() &&
748       D->getInit() == 0 &&
749       !D->hasUninstantiatedDefaultArg())  // No default expr.
750     AbbrevToUse = Writer.getDeclParmVarAbbrev();
751 
752   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
753   // just us assuming it.
754   assert(!D->isInvalidDecl() && "Shouldn't emit invalid decls");
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->getPreviousDeclaration() == 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   VisitNamedDecl(D);
814   Record.push_back(D->isInline());
815   Writer.AddSourceLocation(D->getLocStart(), Record);
816   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
817   Writer.AddDeclRef(D->getNextNamespace(), Record);
818 
819   // Only write one reference--original or anonymous
820   Record.push_back(D->isOriginalNamespace());
821   if (D->isOriginalNamespace())
822     Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
823   else
824     Writer.AddDeclRef(D->getOriginalNamespace(), Record);
825   Code = serialization::DECL_NAMESPACE;
826 
827   if (Writer.hasChain() && !D->isOriginalNamespace() &&
828       D->getOriginalNamespace()->isFromASTFile()) {
829     NamespaceDecl *NS = D->getOriginalNamespace();
830     Writer.AddUpdatedDeclContext(NS);
831 
832     // Make sure all visible decls are written. They will be recorded later.
833     NS->lookup(DeclarationName());
834     StoredDeclsMap *Map = static_cast<StoredDeclsMap*>(NS->getLookupPtr());
835     if (Map) {
836       for (StoredDeclsMap::iterator D = Map->begin(), DEnd = Map->end();
837            D != DEnd; ++D) {
838         DeclContext::lookup_result Result = D->second.getLookupResult();
839         while (Result.first != Result.second) {
840           Writer.GetDeclRef(*Result.first);
841           ++Result.first;
842         }
843       }
844     }
845   }
846 
847   if (Writer.hasChain() && D->isAnonymousNamespace() && !D->getNextNamespace()){
848     // This is a most recent reopening of the anonymous namespace. If its parent
849     // is in a previous PCH (or is the TU), mark that parent for update, because
850     // the original namespace always points to the latest re-opening of its
851     // anonymous namespace.
852     Decl *Parent = cast<Decl>(
853         D->getParent()->getRedeclContext()->getPrimaryContext());
854     if (Parent->isFromASTFile() || isa<TranslationUnitDecl>(Parent)) {
855       ASTWriter::UpdateRecord &Record = Writer.DeclUpdates[Parent];
856       Record.push_back(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE);
857       Writer.AddDeclRef(D, Record);
858     }
859   }
860 }
861 
862 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
863   VisitNamedDecl(D);
864   Writer.AddSourceLocation(D->getNamespaceLoc(), Record);
865   Writer.AddSourceLocation(D->getTargetNameLoc(), Record);
866   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
867   Writer.AddDeclRef(D->getNamespace(), Record);
868   Code = serialization::DECL_NAMESPACE_ALIAS;
869 }
870 
871 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
872   VisitNamedDecl(D);
873   Writer.AddSourceLocation(D->getUsingLocation(), Record);
874   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
875   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
876   Writer.AddDeclRef(D->FirstUsingShadow, Record);
877   Record.push_back(D->isTypeName());
878   Writer.AddDeclRef(Context.getInstantiatedFromUsingDecl(D), Record);
879   Code = serialization::DECL_USING;
880 }
881 
882 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
883   VisitNamedDecl(D);
884   Writer.AddDeclRef(D->getTargetDecl(), Record);
885   Writer.AddDeclRef(D->UsingOrNextShadow, Record);
886   Writer.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D), Record);
887   Code = serialization::DECL_USING_SHADOW;
888 }
889 
890 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
891   VisitNamedDecl(D);
892   Writer.AddSourceLocation(D->getUsingLoc(), Record);
893   Writer.AddSourceLocation(D->getNamespaceKeyLocation(), Record);
894   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
895   Writer.AddDeclRef(D->getNominatedNamespace(), Record);
896   Writer.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()), Record);
897   Code = serialization::DECL_USING_DIRECTIVE;
898 }
899 
900 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
901   VisitValueDecl(D);
902   Writer.AddSourceLocation(D->getUsingLoc(), Record);
903   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
904   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
905   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
906 }
907 
908 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
909                                                UnresolvedUsingTypenameDecl *D) {
910   VisitTypeDecl(D);
911   Writer.AddSourceLocation(D->getTypenameLoc(), Record);
912   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
913   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
914 }
915 
916 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
917   VisitRecordDecl(D);
918 
919   CXXRecordDecl *DefinitionDecl = 0;
920   if (D->DefinitionData)
921     DefinitionDecl = D->DefinitionData->Definition;
922   Writer.AddDeclRef(DefinitionDecl, Record);
923   if (D == DefinitionDecl)
924     Writer.AddCXXDefinitionData(D, Record);
925 
926   enum {
927     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
928   };
929   if (ClassTemplateDecl *TemplD = D->getDescribedClassTemplate()) {
930     Record.push_back(CXXRecTemplate);
931     Writer.AddDeclRef(TemplD, Record);
932   } else if (MemberSpecializationInfo *MSInfo
933                = D->getMemberSpecializationInfo()) {
934     Record.push_back(CXXRecMemberSpecialization);
935     Writer.AddDeclRef(MSInfo->getInstantiatedFrom(), Record);
936     Record.push_back(MSInfo->getTemplateSpecializationKind());
937     Writer.AddSourceLocation(MSInfo->getPointOfInstantiation(), Record);
938   } else {
939     Record.push_back(CXXRecNotTemplate);
940   }
941 
942   // Store the key function to avoid deserializing every method so we can
943   // compute it.
944   if (D->IsCompleteDefinition)
945     Writer.AddDeclRef(Context.getKeyFunction(D), Record);
946 
947   Code = serialization::DECL_CXX_RECORD;
948 }
949 
950 void ASTDeclWriter::VisitCXXMethodDecl(CXXMethodDecl *D) {
951   VisitFunctionDecl(D);
952   Record.push_back(D->size_overridden_methods());
953   for (CXXMethodDecl::method_iterator
954          I = D->begin_overridden_methods(), E = D->end_overridden_methods();
955          I != E; ++I)
956     Writer.AddDeclRef(*I, Record);
957   Code = serialization::DECL_CXX_METHOD;
958 }
959 
960 void ASTDeclWriter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
961   VisitCXXMethodDecl(D);
962 
963   Record.push_back(D->IsExplicitSpecified);
964   Record.push_back(D->ImplicitlyDefined);
965   Writer.AddCXXCtorInitializers(D->CtorInitializers, D->NumCtorInitializers,
966                                 Record);
967 
968   Code = serialization::DECL_CXX_CONSTRUCTOR;
969 }
970 
971 void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
972   VisitCXXMethodDecl(D);
973 
974   Record.push_back(D->ImplicitlyDefined);
975   Writer.AddDeclRef(D->OperatorDelete, Record);
976 
977   Code = serialization::DECL_CXX_DESTRUCTOR;
978 }
979 
980 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
981   VisitCXXMethodDecl(D);
982   Record.push_back(D->IsExplicitSpecified);
983   Code = serialization::DECL_CXX_CONVERSION;
984 }
985 
986 void ASTDeclWriter::VisitImportDecl(ImportDecl *D) {
987   VisitDecl(D);
988   ArrayRef<SourceLocation> IdentifierLocs = D->getIdentifierLocs();
989   Record.push_back(!IdentifierLocs.empty());
990   if (IdentifierLocs.empty()) {
991     Writer.AddSourceLocation(D->getLocEnd(), Record);
992     Record.push_back(1);
993   } else {
994     for (unsigned I = 0, N = IdentifierLocs.size(); I != N; ++I)
995       Writer.AddSourceLocation(IdentifierLocs[I], Record);
996     Record.push_back(IdentifierLocs.size());
997   }
998   // Note: the number of source locations must always be the last element in
999   // the record.
1000   Code = serialization::DECL_IMPORT;
1001 }
1002 
1003 void ASTDeclWriter::VisitAccessSpecDecl(AccessSpecDecl *D) {
1004   VisitDecl(D);
1005   Writer.AddSourceLocation(D->getColonLoc(), Record);
1006   Code = serialization::DECL_ACCESS_SPEC;
1007 }
1008 
1009 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
1010   VisitDecl(D);
1011   Record.push_back(D->Friend.is<TypeSourceInfo*>());
1012   if (D->Friend.is<TypeSourceInfo*>())
1013     Writer.AddTypeSourceInfo(D->Friend.get<TypeSourceInfo*>(), Record);
1014   else
1015     Writer.AddDeclRef(D->Friend.get<NamedDecl*>(), Record);
1016   Writer.AddDeclRef(D->getNextFriend(), Record);
1017   Record.push_back(D->UnsupportedFriend);
1018   Writer.AddSourceLocation(D->FriendLoc, Record);
1019   Code = serialization::DECL_FRIEND;
1020 }
1021 
1022 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
1023   VisitDecl(D);
1024   Record.push_back(D->getNumTemplateParameters());
1025   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
1026     Writer.AddTemplateParameterList(D->getTemplateParameterList(i), Record);
1027   Record.push_back(D->getFriendDecl() != 0);
1028   if (D->getFriendDecl())
1029     Writer.AddDeclRef(D->getFriendDecl(), Record);
1030   else
1031     Writer.AddTypeSourceInfo(D->getFriendType(), Record);
1032   Writer.AddSourceLocation(D->getFriendLoc(), Record);
1033   Code = serialization::DECL_FRIEND_TEMPLATE;
1034 }
1035 
1036 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
1037   VisitNamedDecl(D);
1038 
1039   Writer.AddDeclRef(D->getTemplatedDecl(), Record);
1040   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1041 }
1042 
1043 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
1044   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
1045   // getCommonPtr() can be used while this is still initializing.
1046   enum { FirstDeclaration, FirstInFile, PointsToPrevious };
1047   RedeclarableTemplateDecl *Prev = D->getPreviousDeclaration();
1048   RedeclarableTemplateDecl *First = 0;
1049   if (!Prev) {
1050     Record.push_back(FirstDeclaration);
1051 
1052     // This declaration owns the 'common' pointer, so serialize that data now.
1053     Writer.AddDeclRef(D->getInstantiatedFromMemberTemplate(), Record);
1054     if (D->getInstantiatedFromMemberTemplate())
1055       Record.push_back(D->isMemberSpecialization());
1056   } else {
1057     First = D->getFirstDeclaration();
1058     Record.push_back(Prev->isFromASTFile()? FirstInFile : PointsToPrevious);
1059     Writer.AddDeclRef(First, Record);
1060     Writer.AddDeclRef(Prev, Record);
1061   }
1062 
1063   if (D->getMostRecentDeclaration() != D && (!Prev || Prev->isFromASTFile())) {
1064     if (!First)
1065       First = D->getFirstDeclaration();
1066 
1067     // Capture the set of redeclarations in this file.
1068     LocalRedeclarationsInfo LocalInfo = {
1069       Writer.GetDeclRef(First),
1070       Writer.GetDeclRef(D),
1071       Writer.GetDeclRef(D->getMostRecentDeclaration())
1072     };
1073     Writer.LocalRedeclarations.push_back(LocalInfo);
1074   }
1075 
1076   VisitTemplateDecl(D);
1077   Record.push_back(D->getIdentifierNamespace());
1078 }
1079 
1080 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1081   VisitRedeclarableTemplateDecl(D);
1082 
1083   if (D->getPreviousDeclaration() == 0) {
1084     typedef llvm::FoldingSet<ClassTemplateSpecializationDecl> CTSDSetTy;
1085     CTSDSetTy &CTSDSet = D->getSpecializations();
1086     Record.push_back(CTSDSet.size());
1087     for (CTSDSetTy::iterator I=CTSDSet.begin(), E = CTSDSet.end(); I!=E; ++I) {
1088       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1089       Writer.AddDeclRef(&*I, Record);
1090     }
1091 
1092     typedef llvm::FoldingSet<ClassTemplatePartialSpecializationDecl> CTPSDSetTy;
1093     CTPSDSetTy &CTPSDSet = D->getPartialSpecializations();
1094     Record.push_back(CTPSDSet.size());
1095     for (CTPSDSetTy::iterator I=CTPSDSet.begin(), E=CTPSDSet.end(); I!=E; ++I) {
1096       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1097       Writer.AddDeclRef(&*I, Record);
1098     }
1099 
1100     // InjectedClassNameType is computed, no need to write it.
1101   }
1102   Code = serialization::DECL_CLASS_TEMPLATE;
1103 }
1104 
1105 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
1106                                            ClassTemplateSpecializationDecl *D) {
1107   VisitCXXRecordDecl(D);
1108 
1109   llvm::PointerUnion<ClassTemplateDecl *,
1110                      ClassTemplatePartialSpecializationDecl *> InstFrom
1111     = D->getSpecializedTemplateOrPartial();
1112   if (Decl *InstFromD = InstFrom.dyn_cast<ClassTemplateDecl *>()) {
1113     Writer.AddDeclRef(InstFromD, Record);
1114   } else {
1115     Writer.AddDeclRef(InstFrom.get<ClassTemplatePartialSpecializationDecl *>(),
1116                       Record);
1117     Writer.AddTemplateArgumentList(&D->getTemplateInstantiationArgs(), Record);
1118   }
1119 
1120   // Explicit info.
1121   Writer.AddTypeSourceInfo(D->getTypeAsWritten(), Record);
1122   if (D->getTypeAsWritten()) {
1123     Writer.AddSourceLocation(D->getExternLoc(), Record);
1124     Writer.AddSourceLocation(D->getTemplateKeywordLoc(), Record);
1125   }
1126 
1127   Writer.AddTemplateArgumentList(&D->getTemplateArgs(), Record);
1128   Writer.AddSourceLocation(D->getPointOfInstantiation(), Record);
1129   Record.push_back(D->getSpecializationKind());
1130 
1131   if (D->isCanonicalDecl()) {
1132     // When reading, we'll add it to the folding set of the following template.
1133     Writer.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl(), Record);
1134   }
1135 
1136   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
1137 }
1138 
1139 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
1140                                     ClassTemplatePartialSpecializationDecl *D) {
1141   VisitClassTemplateSpecializationDecl(D);
1142 
1143   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1144 
1145   Record.push_back(D->getNumTemplateArgsAsWritten());
1146   for (int i = 0, e = D->getNumTemplateArgsAsWritten(); i != e; ++i)
1147     Writer.AddTemplateArgumentLoc(D->getTemplateArgsAsWritten()[i], Record);
1148 
1149   Record.push_back(D->getSequenceNumber());
1150 
1151   // These are read/set from/to the first declaration.
1152   if (D->getPreviousDeclaration() == 0) {
1153     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
1154     Record.push_back(D->isMemberSpecialization());
1155   }
1156 
1157   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
1158 }
1159 
1160 void ASTDeclWriter::VisitClassScopeFunctionSpecializationDecl(
1161                                     ClassScopeFunctionSpecializationDecl *D) {
1162   VisitDecl(D);
1163   Writer.AddDeclRef(D->getSpecialization(), Record);
1164   Code = serialization::DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION;
1165 }
1166 
1167 
1168 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1169   VisitRedeclarableTemplateDecl(D);
1170 
1171   if (D->getPreviousDeclaration() == 0) {
1172     // This FunctionTemplateDecl owns the CommonPtr; write it.
1173 
1174     // Write the function specialization declarations.
1175     Record.push_back(D->getSpecializations().size());
1176     for (llvm::FoldingSet<FunctionTemplateSpecializationInfo>::iterator
1177            I = D->getSpecializations().begin(),
1178            E = D->getSpecializations().end()   ; I != E; ++I) {
1179       assert(I->Function->isCanonicalDecl() &&
1180              "Expected only canonical decls in set");
1181       Writer.AddDeclRef(I->Function, Record);
1182     }
1183   }
1184   Code = serialization::DECL_FUNCTION_TEMPLATE;
1185 }
1186 
1187 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1188   VisitTypeDecl(D);
1189 
1190   Record.push_back(D->wasDeclaredWithTypename());
1191   Record.push_back(D->defaultArgumentWasInherited());
1192   Writer.AddTypeSourceInfo(D->getDefaultArgumentInfo(), Record);
1193 
1194   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1195 }
1196 
1197 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1198   // For an expanded parameter pack, record the number of expansion types here
1199   // so that it's easier for
1200   if (D->isExpandedParameterPack())
1201     Record.push_back(D->getNumExpansionTypes());
1202 
1203   VisitDeclaratorDecl(D);
1204   // TemplateParmPosition.
1205   Record.push_back(D->getDepth());
1206   Record.push_back(D->getPosition());
1207 
1208   if (D->isExpandedParameterPack()) {
1209     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1210       Writer.AddTypeRef(D->getExpansionType(I), Record);
1211       Writer.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I), Record);
1212     }
1213 
1214     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1215   } else {
1216     // Rest of NonTypeTemplateParmDecl.
1217     Record.push_back(D->isParameterPack());
1218     Record.push_back(D->getDefaultArgument() != 0);
1219     if (D->getDefaultArgument()) {
1220       Writer.AddStmt(D->getDefaultArgument());
1221       Record.push_back(D->defaultArgumentWasInherited());
1222     }
1223     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1224   }
1225 }
1226 
1227 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1228   VisitTemplateDecl(D);
1229   // TemplateParmPosition.
1230   Record.push_back(D->getDepth());
1231   Record.push_back(D->getPosition());
1232   // Rest of TemplateTemplateParmDecl.
1233   Writer.AddTemplateArgumentLoc(D->getDefaultArgument(), Record);
1234   Record.push_back(D->defaultArgumentWasInherited());
1235   Record.push_back(D->isParameterPack());
1236   Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1237 }
1238 
1239 void ASTDeclWriter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
1240   VisitRedeclarableTemplateDecl(D);
1241   Code = serialization::DECL_TYPE_ALIAS_TEMPLATE;
1242 }
1243 
1244 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1245   VisitDecl(D);
1246   Writer.AddStmt(D->getAssertExpr());
1247   Writer.AddStmt(D->getMessage());
1248   Writer.AddSourceLocation(D->getRParenLoc(), Record);
1249   Code = serialization::DECL_STATIC_ASSERT;
1250 }
1251 
1252 /// \brief Emit the DeclContext part of a declaration context decl.
1253 ///
1254 /// \param LexicalOffset the offset at which the DECL_CONTEXT_LEXICAL
1255 /// block for this declaration context is stored. May be 0 to indicate
1256 /// that there are no declarations stored within this context.
1257 ///
1258 /// \param VisibleOffset the offset at which the DECL_CONTEXT_VISIBLE
1259 /// block for this declaration context is stored. May be 0 to indicate
1260 /// that there are no declarations visible from this context. Note
1261 /// that this value will not be emitted for non-primary declaration
1262 /// contexts.
1263 void ASTDeclWriter::VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
1264                                      uint64_t VisibleOffset) {
1265   Record.push_back(LexicalOffset);
1266   Record.push_back(VisibleOffset);
1267 }
1268 
1269 template <typename T>
1270 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1271   enum { FirstDeclaration = 0, FirstInFile, PointsToPrevious };
1272   T *Prev = D->getPreviousDeclaration();
1273   T *First = D->getFirstDeclaration();
1274 
1275   if (!Prev) {
1276     Record.push_back(FirstDeclaration);
1277   } else {
1278     Record.push_back(Prev->isFromASTFile()? FirstInFile : PointsToPrevious);
1279     Writer.AddDeclRef(First, Record);
1280     Writer.AddDeclRef(D->getPreviousDeclaration(), Record);
1281   }
1282 
1283   if (D->RedeclLink.getPointer() != D && (!Prev || Prev->isFromASTFile())) {
1284     // Capture the set of redeclarations in this file.
1285     LocalRedeclarationsInfo LocalInfo = {
1286       Writer.GetDeclRef(First),
1287       Writer.GetDeclRef(static_cast<T*>(D)),
1288       Writer.GetDeclRef(D->getMostRecentDeclaration())
1289     };
1290     Writer.LocalRedeclarations.push_back(LocalInfo);
1291   }
1292 }
1293 
1294 //===----------------------------------------------------------------------===//
1295 // ASTWriter Implementation
1296 //===----------------------------------------------------------------------===//
1297 
1298 void ASTWriter::WriteDeclsBlockAbbrevs() {
1299   using namespace llvm;
1300 
1301   BitCodeAbbrev *Abv;
1302 
1303   // Abbreviation for DECL_FIELD
1304   Abv = new BitCodeAbbrev();
1305   Abv->Add(BitCodeAbbrevOp(serialization::DECL_FIELD));
1306   // Decl
1307   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1308   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1309   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1310   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1311   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1312   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1313   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1314   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1315   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1316   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1317   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1318   // NamedDecl
1319   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1320   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1321   // ValueDecl
1322   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1323   // DeclaratorDecl
1324   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1325   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1326   // FieldDecl
1327   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1328   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1329   // Type Source Info
1330   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1331   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1332   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1333   DeclFieldAbbrev = Stream.EmitAbbrev(Abv);
1334 
1335   // Abbreviation for DECL_OBJC_IVAR
1336   Abv = new BitCodeAbbrev();
1337   Abv->Add(BitCodeAbbrevOp(serialization::DECL_OBJC_IVAR));
1338   // Decl
1339   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1340   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1341   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1342   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1343   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1344   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1345   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1346   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1347   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1348   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1349   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1350   // NamedDecl
1351   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1352   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1353   // ValueDecl
1354   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1355   // DeclaratorDecl
1356   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1357   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1358   // FieldDecl
1359   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1360   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1361   // ObjC Ivar
1362   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getAccessControl
1363   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getSynthesize
1364   // Type Source Info
1365   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1366   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1367   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1368   DeclObjCIvarAbbrev = Stream.EmitAbbrev(Abv);
1369 
1370   // Abbreviation for DECL_ENUM
1371   Abv = new BitCodeAbbrev();
1372   Abv->Add(BitCodeAbbrevOp(serialization::DECL_ENUM));
1373   // Redeclarable
1374   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1375   // Decl
1376   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1377   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1378   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1379   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1380   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1381   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1382   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1383   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1384   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1385   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1386   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1387   // NamedDecl
1388   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1389   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1390   // TypeDecl
1391   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1392   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1393   // TagDecl
1394   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1395   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1396   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1397   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1398   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1399   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1400   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1401   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1402   // EnumDecl
1403   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddTypeRef
1404   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IntegerType
1405   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getPromotionType
1406   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumPositiveBits
1407   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumNegativeBits
1408   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScoped
1409   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScopedUsingClassTag
1410   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isFixed
1411   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InstantiatedMembEnum
1412   // DC
1413   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1414   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1415   DeclEnumAbbrev = Stream.EmitAbbrev(Abv);
1416 
1417   // Abbreviation for DECL_RECORD
1418   Abv = new BitCodeAbbrev();
1419   Abv->Add(BitCodeAbbrevOp(serialization::DECL_RECORD));
1420   // Redeclarable
1421   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1422   // Decl
1423   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1424   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1425   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1426   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1427   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1428   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1429   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1430   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1431   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1432   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1433   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1434   // NamedDecl
1435   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1436   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1437   // TypeDecl
1438   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1439   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1440   // TagDecl
1441   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1442   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1443   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1444   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1445   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1446   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1447   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1448   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1449   // RecordDecl
1450   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // FlexibleArrayMember
1451   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // AnonymousStructUnion
1452   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasObjectMember
1453   // DC
1454   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1455   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1456   DeclRecordAbbrev = Stream.EmitAbbrev(Abv);
1457 
1458   // Abbreviation for DECL_PARM_VAR
1459   Abv = new BitCodeAbbrev();
1460   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1461   // Redeclarable
1462   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1463   // Decl
1464   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1465   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1466   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1467   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1468   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1469   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1470   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1471   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1472   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1473   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1474   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1475   // NamedDecl
1476   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1477   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1478   // ValueDecl
1479   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1480   // DeclaratorDecl
1481   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1482   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1483   // VarDecl
1484   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClass
1485   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClassAsWritten
1486   Abv->Add(BitCodeAbbrevOp(0));                       // isThreadSpecified
1487   Abv->Add(BitCodeAbbrevOp(0));                       // hasCXXDirectInitializer
1488   Abv->Add(BitCodeAbbrevOp(0));                       // isExceptionVariable
1489   Abv->Add(BitCodeAbbrevOp(0));                       // isNRVOVariable
1490   Abv->Add(BitCodeAbbrevOp(0));                       // isCXXForRangeDecl
1491   Abv->Add(BitCodeAbbrevOp(0));                       // isARCPseudoStrong
1492   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
1493   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
1494   // ParmVarDecl
1495   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsObjCMethodParameter
1496   Abv->Add(BitCodeAbbrevOp(0));                       // ScopeDepth
1497   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ScopeIndex
1498   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
1499   Abv->Add(BitCodeAbbrevOp(0));                       // KNRPromoted
1500   Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
1501   Abv->Add(BitCodeAbbrevOp(0));                   // HasUninstantiatedDefaultArg
1502   // Type Source Info
1503   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1504   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1505   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1506   DeclParmVarAbbrev = Stream.EmitAbbrev(Abv);
1507 
1508   // Abbreviation for DECL_TYPEDEF
1509   Abv = new BitCodeAbbrev();
1510   Abv->Add(BitCodeAbbrevOp(serialization::DECL_TYPEDEF));
1511   // Redeclarable
1512   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1513   // Decl
1514   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1515   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1516   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1517   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1518   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1519   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1520   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1521   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1522   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1523   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1524   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1525   // NamedDecl
1526   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1527   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1528   // TypeDecl
1529   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1530   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1531   // TypedefDecl
1532   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1533   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1534   DeclTypedefAbbrev = Stream.EmitAbbrev(Abv);
1535 
1536   // Abbreviation for DECL_VAR
1537   Abv = new BitCodeAbbrev();
1538   Abv->Add(BitCodeAbbrevOp(serialization::DECL_VAR));
1539   // Redeclarable
1540   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1541   // Decl
1542   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1543   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1544   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1545   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1546   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1547   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1548   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1549   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1550   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1551   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1552   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1553   // NamedDecl
1554   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1555   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1556   // ValueDecl
1557   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1558   // DeclaratorDecl
1559   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1560   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1561   // VarDecl
1562   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClass
1563   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClassAsWritten
1564   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isThreadSpecified
1565   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // CXXDirectInitializer
1566   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
1567   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
1568   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
1569   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
1570   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasInit
1571   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasMemberSpecInfo
1572   // Type Source Info
1573   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1574   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1575   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1576   DeclVarAbbrev = Stream.EmitAbbrev(Abv);
1577 
1578   // Abbreviation for EXPR_DECL_REF
1579   Abv = new BitCodeAbbrev();
1580   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_DECL_REF));
1581   //Stmt
1582   //Expr
1583   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1584   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1585   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1586   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1587   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1588   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1589   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1590   //DeclRefExpr
1591   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HasQualifier
1592   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //GetDeclFound
1593   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ExplicitTemplateArgs
1594   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HadMultipleCandidates
1595   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclRef
1596   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1597   DeclRefExprAbbrev = Stream.EmitAbbrev(Abv);
1598 
1599   // Abbreviation for EXPR_INTEGER_LITERAL
1600   Abv = new BitCodeAbbrev();
1601   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_INTEGER_LITERAL));
1602   //Stmt
1603   //Expr
1604   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1605   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1606   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1607   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1608   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1609   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1610   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1611   //Integer Literal
1612   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1613   Abv->Add(BitCodeAbbrevOp(32));                      // Bit Width
1614   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Value
1615   IntegerLiteralAbbrev = Stream.EmitAbbrev(Abv);
1616 
1617   // Abbreviation for EXPR_CHARACTER_LITERAL
1618   Abv = new BitCodeAbbrev();
1619   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_CHARACTER_LITERAL));
1620   //Stmt
1621   //Expr
1622   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1623   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1624   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1625   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1626   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1627   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1628   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1629   //Character Literal
1630   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getValue
1631   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1632   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //IsWide
1633   CharacterLiteralAbbrev = Stream.EmitAbbrev(Abv);
1634 
1635   Abv = new BitCodeAbbrev();
1636   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
1637   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1638   DeclContextLexicalAbbrev = Stream.EmitAbbrev(Abv);
1639 
1640   Abv = new BitCodeAbbrev();
1641   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
1642   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1643   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1644   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(Abv);
1645 }
1646 
1647 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
1648 /// consumers of the AST.
1649 ///
1650 /// Such decls will always be deserialized from the AST file, so we would like
1651 /// this to be as restrictive as possible. Currently the predicate is driven by
1652 /// code generation requirements, if other clients have a different notion of
1653 /// what is "required" then we may have to consider an alternate scheme where
1654 /// clients can iterate over the top-level decls and get information on them,
1655 /// without necessary deserializing them. We could explicitly require such
1656 /// clients to use a separate API call to "realize" the decl. This should be
1657 /// relatively painless since they would presumably only do it for top-level
1658 /// decls.
1659 static bool isRequiredDecl(const Decl *D, ASTContext &Context) {
1660   // An ObjCMethodDecl is never considered as "required" because its
1661   // implementation container always is.
1662 
1663   // File scoped assembly or obj-c implementation must be seen.
1664   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplDecl>(D))
1665     return true;
1666 
1667   return Context.DeclMustBeEmitted(D);
1668 }
1669 
1670 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
1671   // Switch case IDs are per Decl.
1672   ClearSwitchCaseIDs();
1673 
1674   RecordData Record;
1675   ASTDeclWriter W(*this, Context, Record);
1676 
1677   // If this declaration is also a DeclContext, write blocks for the
1678   // declarations that lexically stored inside its context and those
1679   // declarations that are visible from its context. These blocks
1680   // are written before the declaration itself so that we can put
1681   // their offsets into the record for the declaration.
1682   uint64_t LexicalOffset = 0;
1683   uint64_t VisibleOffset = 0;
1684   DeclContext *DC = dyn_cast<DeclContext>(D);
1685   if (DC) {
1686     LexicalOffset = WriteDeclContextLexicalBlock(Context, DC);
1687     VisibleOffset = WriteDeclContextVisibleBlock(Context, DC);
1688   }
1689 
1690   // Determine the ID for this declaration
1691   serialization::DeclID &IDR = DeclIDs[D];
1692   if (IDR == 0)
1693     IDR = NextDeclID++;
1694   serialization::DeclID ID = IDR;
1695 
1696   if (ID < FirstDeclID) {
1697     // We're replacing a decl in a previous file.
1698     ReplacedDecls.push_back(ReplacedDeclInfo(ID, Stream.GetCurrentBitNo(),
1699                                              D->getLocation()));
1700   } else {
1701     unsigned Index = ID - FirstDeclID;
1702 
1703     // Record the offset for this declaration
1704     SourceLocation Loc = D->getLocation();
1705     if (DeclOffsets.size() == Index)
1706       DeclOffsets.push_back(DeclOffset(Loc, Stream.GetCurrentBitNo()));
1707     else if (DeclOffsets.size() < Index) {
1708       DeclOffsets.resize(Index+1);
1709       DeclOffsets[Index].setLocation(Loc);
1710       DeclOffsets[Index].BitOffset = Stream.GetCurrentBitNo();
1711     }
1712 
1713     SourceManager &SM = Context.getSourceManager();
1714     if (Loc.isValid() && SM.isLocalSourceLocation(Loc))
1715       associateDeclWithFile(D, ID);
1716   }
1717 
1718   // Build and emit a record for this declaration
1719   Record.clear();
1720   W.Code = (serialization::DeclCode)0;
1721   W.AbbrevToUse = 0;
1722   W.Visit(D);
1723   if (DC) W.VisitDeclContext(DC, LexicalOffset, VisibleOffset);
1724 
1725   if (!W.Code)
1726     llvm::report_fatal_error(StringRef("unexpected declaration kind '") +
1727                             D->getDeclKindName() + "'");
1728   Stream.EmitRecord(W.Code, Record, W.AbbrevToUse);
1729 
1730   // Flush any expressions that were written as part of this declaration.
1731   FlushStmts();
1732 
1733   // Flush C++ base specifiers, if there are any.
1734   FlushCXXBaseSpecifiers();
1735 
1736   // Note "external" declarations so that we can add them to a record in the
1737   // AST file later.
1738   //
1739   // FIXME: This should be renamed, the predicate is much more complicated.
1740   if (isRequiredDecl(D, Context))
1741     ExternalDefinitions.push_back(ID);
1742 }
1743