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 VisitVarTemplateSpecializationDecl(VarTemplateSpecializationDecl *D);
72     void VisitVarTemplatePartialSpecializationDecl(
73         VarTemplatePartialSpecializationDecl *D);
74     void VisitClassScopeFunctionSpecializationDecl(
75                                        ClassScopeFunctionSpecializationDecl *D);
76     void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
77     void VisitValueDecl(ValueDecl *D);
78     void VisitEnumConstantDecl(EnumConstantDecl *D);
79     void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
80     void VisitDeclaratorDecl(DeclaratorDecl *D);
81     void VisitFunctionDecl(FunctionDecl *D);
82     void VisitCXXMethodDecl(CXXMethodDecl *D);
83     void VisitCXXConstructorDecl(CXXConstructorDecl *D);
84     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
85     void VisitCXXConversionDecl(CXXConversionDecl *D);
86     void VisitFieldDecl(FieldDecl *D);
87     void VisitMSPropertyDecl(MSPropertyDecl *D);
88     void VisitIndirectFieldDecl(IndirectFieldDecl *D);
89     void VisitVarDecl(VarDecl *D);
90     void VisitImplicitParamDecl(ImplicitParamDecl *D);
91     void VisitParmVarDecl(ParmVarDecl *D);
92     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
93     void VisitTemplateDecl(TemplateDecl *D);
94     void VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
95     void VisitClassTemplateDecl(ClassTemplateDecl *D);
96     void VisitVarTemplateDecl(VarTemplateDecl *D);
97     void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
98     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
99     void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
100     void VisitUsingDecl(UsingDecl *D);
101     void VisitUsingShadowDecl(UsingShadowDecl *D);
102     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
103     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
104     void VisitImportDecl(ImportDecl *D);
105     void VisitAccessSpecDecl(AccessSpecDecl *D);
106     void VisitFriendDecl(FriendDecl *D);
107     void VisitFriendTemplateDecl(FriendTemplateDecl *D);
108     void VisitStaticAssertDecl(StaticAssertDecl *D);
109     void VisitBlockDecl(BlockDecl *D);
110     void VisitCapturedDecl(CapturedDecl *D);
111     void VisitEmptyDecl(EmptyDecl *D);
112 
113     void VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
114                           uint64_t VisibleOffset);
115     template <typename T> void VisitRedeclarable(Redeclarable<T> *D);
116 
117 
118     // FIXME: Put in the same order is DeclNodes.td?
119     void VisitObjCMethodDecl(ObjCMethodDecl *D);
120     void VisitObjCContainerDecl(ObjCContainerDecl *D);
121     void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
122     void VisitObjCIvarDecl(ObjCIvarDecl *D);
123     void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
124     void VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D);
125     void VisitObjCCategoryDecl(ObjCCategoryDecl *D);
126     void VisitObjCImplDecl(ObjCImplDecl *D);
127     void VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D);
128     void VisitObjCImplementationDecl(ObjCImplementationDecl *D);
129     void VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D);
130     void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
131     void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
132     void VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D);
133 
134     void AddFunctionDefinition(const FunctionDecl *FD) {
135       assert(FD->doesThisDeclarationHaveABody());
136       if (auto *CD = dyn_cast<CXXConstructorDecl>(FD))
137         Writer.AddCXXCtorInitializers(CD->CtorInitializers,
138                                       CD->NumCtorInitializers, Record);
139       Writer.AddStmt(FD->getBody());
140     }
141 
142     /// Get the specialization decl from an entry in the specialization list.
143     template <typename EntryType>
144     typename RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::DeclType *
145     getSpecializationDecl(EntryType &T) {
146       return RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::getDecl(&T);
147     }
148 
149     /// Get the list of partial specializations from a template's common ptr.
150     template<typename T>
151     decltype(T::PartialSpecializations) &getPartialSpecializations(T *Common) {
152       return Common->PartialSpecializations;
153     }
154     ArrayRef<Decl> getPartialSpecializations(FunctionTemplateDecl::Common *) {
155       return None;
156     }
157 
158     template<typename Decl>
159     void AddTemplateSpecializations(Decl *D) {
160       auto *Common = D->getCommonPtr();
161 
162       // If we have any lazy specializations, and the external AST source is
163       // our chained AST reader, we can just write out the DeclIDs. Otherwise,
164       // we need to resolve them to actual declarations.
165       if (Writer.Chain != Writer.Context->getExternalSource() &&
166           Common->LazySpecializations) {
167         D->LoadLazySpecializations();
168         assert(!Common->LazySpecializations);
169       }
170 
171       auto &Specializations = Common->Specializations;
172       auto &&PartialSpecializations = getPartialSpecializations(Common);
173       ArrayRef<DeclID> LazySpecializations;
174       if (auto *LS = Common->LazySpecializations)
175         LazySpecializations = ArrayRef<DeclID>(LS + 1, LS + 1 + LS[0]);
176 
177       Record.push_back(Specializations.size() +
178                        PartialSpecializations.size() +
179                        LazySpecializations.size());
180       for (auto &Entry : Specializations) {
181         auto *D = getSpecializationDecl(Entry);
182         assert(D->isCanonicalDecl() && "non-canonical decl in set");
183         Writer.AddDeclRef(D, Record);
184       }
185       for (auto &Entry : PartialSpecializations) {
186         auto *D = getSpecializationDecl(Entry);
187         assert(D->isCanonicalDecl() && "non-canonical decl in set");
188         Writer.AddDeclRef(D, Record);
189       }
190       for (DeclID ID : LazySpecializations)
191         Record.push_back(ID);
192     }
193   };
194 }
195 
196 void ASTDeclWriter::Visit(Decl *D) {
197   DeclVisitor<ASTDeclWriter>::Visit(D);
198 
199   // Source locations require array (variable-length) abbreviations.  The
200   // abbreviation infrastructure requires that arrays are encoded last, so
201   // we handle it here in the case of those classes derived from DeclaratorDecl
202   if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)){
203     Writer.AddTypeSourceInfo(DD->getTypeSourceInfo(), Record);
204   }
205 
206   // Handle FunctionDecl's body here and write it after all other Stmts/Exprs
207   // have been written. We want it last because we will not read it back when
208   // retrieving it from the AST, we'll just lazily set the offset.
209   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
210     Record.push_back(FD->doesThisDeclarationHaveABody());
211     if (FD->doesThisDeclarationHaveABody())
212       Writer.AddStmt(FD->getBody());
213   }
214 }
215 
216 void ASTDeclWriter::VisitDecl(Decl *D) {
217   Writer.AddDeclRef(cast_or_null<Decl>(D->getDeclContext()), Record);
218   Writer.AddDeclRef(cast_or_null<Decl>(D->getLexicalDeclContext()), Record);
219   Record.push_back(D->isInvalidDecl());
220   Record.push_back(D->hasAttrs());
221   if (D->hasAttrs())
222     Writer.WriteAttributes(llvm::makeArrayRef(D->getAttrs().begin(),
223                                               D->getAttrs().size()), Record);
224   Record.push_back(D->isImplicit());
225   Record.push_back(D->isUsed(false));
226   Record.push_back(D->isReferenced());
227   Record.push_back(D->isTopLevelDeclInObjCContainer());
228   Record.push_back(D->getAccess());
229   Record.push_back(D->isModulePrivate());
230   Record.push_back(Writer.inferSubmoduleIDFromLocation(D->getLocation()));
231 
232   // If this declaration injected a name into a context different from its
233   // lexical context, and that context is an imported namespace, we need to
234   // update its visible declarations to include this name.
235   //
236   // This happens when we instantiate a class with a friend declaration or a
237   // function with a local extern declaration, for instance.
238   if (D->isOutOfLine()) {
239     auto *DC = D->getDeclContext();
240     while (auto *NS = dyn_cast<NamespaceDecl>(DC->getRedeclContext())) {
241       if (!NS->isFromASTFile())
242         break;
243       Writer.AddUpdatedDeclContext(NS->getPrimaryContext());
244       if (!NS->isInlineNamespace())
245         break;
246       DC = NS->getParent();
247     }
248   }
249 }
250 
251 void ASTDeclWriter::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
252   llvm_unreachable("Translation units aren't directly serialized");
253 }
254 
255 void ASTDeclWriter::VisitNamedDecl(NamedDecl *D) {
256   VisitDecl(D);
257   Writer.AddDeclarationName(D->getDeclName(), Record);
258   Record.push_back(needsAnonymousDeclarationNumber(D)
259                        ? Writer.getAnonymousDeclarationNumber(D)
260                        : 0);
261 }
262 
263 void ASTDeclWriter::VisitTypeDecl(TypeDecl *D) {
264   VisitNamedDecl(D);
265   Writer.AddSourceLocation(D->getLocStart(), Record);
266   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
267 }
268 
269 void ASTDeclWriter::VisitTypedefNameDecl(TypedefNameDecl *D) {
270   VisitRedeclarable(D);
271   VisitTypeDecl(D);
272   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
273   Record.push_back(D->isModed());
274   if (D->isModed())
275     Writer.AddTypeRef(D->getUnderlyingType(), Record);
276 }
277 
278 void ASTDeclWriter::VisitTypedefDecl(TypedefDecl *D) {
279   VisitTypedefNameDecl(D);
280   if (!D->hasAttrs() &&
281       !D->isImplicit() &&
282       D->getFirstDecl() == D->getMostRecentDecl() &&
283       !D->isInvalidDecl() &&
284       !D->isTopLevelDeclInObjCContainer() &&
285       !D->isModulePrivate() &&
286       !needsAnonymousDeclarationNumber(D) &&
287       D->getDeclName().getNameKind() == DeclarationName::Identifier)
288     AbbrevToUse = Writer.getDeclTypedefAbbrev();
289 
290   Code = serialization::DECL_TYPEDEF;
291 }
292 
293 void ASTDeclWriter::VisitTypeAliasDecl(TypeAliasDecl *D) {
294   VisitTypedefNameDecl(D);
295   Writer.AddDeclRef(D->getDescribedAliasTemplate(), Record);
296   Code = serialization::DECL_TYPEALIAS;
297 }
298 
299 void ASTDeclWriter::VisitTagDecl(TagDecl *D) {
300   VisitRedeclarable(D);
301   VisitTypeDecl(D);
302   Record.push_back(D->getIdentifierNamespace());
303   Record.push_back((unsigned)D->getTagKind()); // FIXME: stable encoding
304   if (!isa<CXXRecordDecl>(D))
305     Record.push_back(D->isCompleteDefinition());
306   Record.push_back(D->isEmbeddedInDeclarator());
307   Record.push_back(D->isFreeStanding());
308   Record.push_back(D->isCompleteDefinitionRequired());
309   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
310 
311   if (D->hasExtInfo()) {
312     Record.push_back(1);
313     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
314   } else if (auto *TD = D->getTypedefNameForAnonDecl()) {
315     Record.push_back(2);
316     Writer.AddDeclRef(TD, Record);
317     Writer.AddIdentifierRef(TD->getDeclName().getAsIdentifierInfo(), Record);
318   } else if (auto *DD = D->getDeclaratorForAnonDecl()) {
319     Record.push_back(3);
320     Writer.AddDeclRef(DD, Record);
321   } else {
322     Record.push_back(0);
323   }
324 }
325 
326 void ASTDeclWriter::VisitEnumDecl(EnumDecl *D) {
327   VisitTagDecl(D);
328   Writer.AddTypeSourceInfo(D->getIntegerTypeSourceInfo(), Record);
329   if (!D->getIntegerTypeSourceInfo())
330     Writer.AddTypeRef(D->getIntegerType(), Record);
331   Writer.AddTypeRef(D->getPromotionType(), Record);
332   Record.push_back(D->getNumPositiveBits());
333   Record.push_back(D->getNumNegativeBits());
334   Record.push_back(D->isScoped());
335   Record.push_back(D->isScopedUsingClassTag());
336   Record.push_back(D->isFixed());
337   if (MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo()) {
338     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
339     Record.push_back(MemberInfo->getTemplateSpecializationKind());
340     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
341   } else {
342     Writer.AddDeclRef(nullptr, Record);
343   }
344 
345   if (!D->hasAttrs() &&
346       !D->isImplicit() &&
347       !D->isUsed(false) &&
348       !D->hasExtInfo() &&
349       !D->getTypedefNameForAnonDecl() &&
350       !D->getDeclaratorForAnonDecl() &&
351       D->getFirstDecl() == D->getMostRecentDecl() &&
352       !D->isInvalidDecl() &&
353       !D->isReferenced() &&
354       !D->isTopLevelDeclInObjCContainer() &&
355       D->getAccess() == AS_none &&
356       !D->isModulePrivate() &&
357       !CXXRecordDecl::classofKind(D->getKind()) &&
358       !D->getIntegerTypeSourceInfo() &&
359       !D->getMemberSpecializationInfo() &&
360       !needsAnonymousDeclarationNumber(D) &&
361       D->getDeclName().getNameKind() == DeclarationName::Identifier)
362     AbbrevToUse = Writer.getDeclEnumAbbrev();
363 
364   Code = serialization::DECL_ENUM;
365 }
366 
367 void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
368   VisitTagDecl(D);
369   Record.push_back(D->hasFlexibleArrayMember());
370   Record.push_back(D->isAnonymousStructOrUnion());
371   Record.push_back(D->hasObjectMember());
372   Record.push_back(D->hasVolatileMember());
373 
374   if (!D->hasAttrs() &&
375       !D->isImplicit() &&
376       !D->isUsed(false) &&
377       !D->hasExtInfo() &&
378       !D->getTypedefNameForAnonDecl() &&
379       !D->getDeclaratorForAnonDecl() &&
380       D->getFirstDecl() == D->getMostRecentDecl() &&
381       !D->isInvalidDecl() &&
382       !D->isReferenced() &&
383       !D->isTopLevelDeclInObjCContainer() &&
384       D->getAccess() == AS_none &&
385       !D->isModulePrivate() &&
386       !CXXRecordDecl::classofKind(D->getKind()) &&
387       !needsAnonymousDeclarationNumber(D) &&
388       D->getDeclName().getNameKind() == DeclarationName::Identifier)
389     AbbrevToUse = Writer.getDeclRecordAbbrev();
390 
391   Code = serialization::DECL_RECORD;
392 }
393 
394 void ASTDeclWriter::VisitValueDecl(ValueDecl *D) {
395   VisitNamedDecl(D);
396   Writer.AddTypeRef(D->getType(), Record);
397 }
398 
399 void ASTDeclWriter::VisitEnumConstantDecl(EnumConstantDecl *D) {
400   VisitValueDecl(D);
401   Record.push_back(D->getInitExpr()? 1 : 0);
402   if (D->getInitExpr())
403     Writer.AddStmt(D->getInitExpr());
404   Writer.AddAPSInt(D->getInitVal(), Record);
405 
406   Code = serialization::DECL_ENUM_CONSTANT;
407 }
408 
409 void ASTDeclWriter::VisitDeclaratorDecl(DeclaratorDecl *D) {
410   VisitValueDecl(D);
411   Writer.AddSourceLocation(D->getInnerLocStart(), Record);
412   Record.push_back(D->hasExtInfo());
413   if (D->hasExtInfo())
414     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
415 }
416 
417 void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
418   VisitRedeclarable(D);
419   VisitDeclaratorDecl(D);
420   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
421   Record.push_back(D->getIdentifierNamespace());
422 
423   // FunctionDecl's body is handled last at ASTWriterDecl::Visit,
424   // after everything else is written.
425 
426   Record.push_back((int)D->SClass); // FIXME: stable encoding
427   Record.push_back(D->IsInline);
428   Record.push_back(D->IsInlineSpecified);
429   Record.push_back(D->IsVirtualAsWritten);
430   Record.push_back(D->IsPure);
431   Record.push_back(D->HasInheritedPrototype);
432   Record.push_back(D->HasWrittenPrototype);
433   Record.push_back(D->IsDeleted);
434   Record.push_back(D->IsTrivial);
435   Record.push_back(D->IsDefaulted);
436   Record.push_back(D->IsExplicitlyDefaulted);
437   Record.push_back(D->HasImplicitReturnZero);
438   Record.push_back(D->IsConstexpr);
439   Record.push_back(D->HasSkippedBody);
440   Record.push_back(D->IsLateTemplateParsed);
441   Record.push_back(D->getLinkageInternal());
442   Writer.AddSourceLocation(D->getLocEnd(), Record);
443 
444   Record.push_back(D->getTemplatedKind());
445   switch (D->getTemplatedKind()) {
446   case FunctionDecl::TK_NonTemplate:
447     break;
448   case FunctionDecl::TK_FunctionTemplate:
449     Writer.AddDeclRef(D->getDescribedFunctionTemplate(), Record);
450     break;
451   case FunctionDecl::TK_MemberSpecialization: {
452     MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo();
453     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
454     Record.push_back(MemberInfo->getTemplateSpecializationKind());
455     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
456     break;
457   }
458   case FunctionDecl::TK_FunctionTemplateSpecialization: {
459     FunctionTemplateSpecializationInfo *
460       FTSInfo = D->getTemplateSpecializationInfo();
461     Writer.AddDeclRef(FTSInfo->getTemplate(), Record);
462     Record.push_back(FTSInfo->getTemplateSpecializationKind());
463 
464     // Template arguments.
465     Writer.AddTemplateArgumentList(FTSInfo->TemplateArguments, Record);
466 
467     // Template args as written.
468     Record.push_back(FTSInfo->TemplateArgumentsAsWritten != nullptr);
469     if (FTSInfo->TemplateArgumentsAsWritten) {
470       Record.push_back(FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs);
471       for (int i=0, e = FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs;
472              i!=e; ++i)
473         Writer.AddTemplateArgumentLoc((*FTSInfo->TemplateArgumentsAsWritten)[i],
474                                       Record);
475       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->LAngleLoc,
476                                Record);
477       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->RAngleLoc,
478                                Record);
479     }
480 
481     Writer.AddSourceLocation(FTSInfo->getPointOfInstantiation(), Record);
482 
483     if (D->isCanonicalDecl()) {
484       // Write the template that contains the specializations set. We will
485       // add a FunctionTemplateSpecializationInfo to it when reading.
486       Writer.AddDeclRef(FTSInfo->getTemplate()->getCanonicalDecl(), Record);
487     }
488     break;
489   }
490   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
491     DependentFunctionTemplateSpecializationInfo *
492       DFTSInfo = D->getDependentSpecializationInfo();
493 
494     // Templates.
495     Record.push_back(DFTSInfo->getNumTemplates());
496     for (int i=0, e = DFTSInfo->getNumTemplates(); i != e; ++i)
497       Writer.AddDeclRef(DFTSInfo->getTemplate(i), Record);
498 
499     // Templates args.
500     Record.push_back(DFTSInfo->getNumTemplateArgs());
501     for (int i=0, e = DFTSInfo->getNumTemplateArgs(); i != e; ++i)
502       Writer.AddTemplateArgumentLoc(DFTSInfo->getTemplateArg(i), Record);
503     Writer.AddSourceLocation(DFTSInfo->getLAngleLoc(), Record);
504     Writer.AddSourceLocation(DFTSInfo->getRAngleLoc(), Record);
505     break;
506   }
507   }
508 
509   Record.push_back(D->param_size());
510   for (auto P : D->params())
511     Writer.AddDeclRef(P, Record);
512   Code = serialization::DECL_FUNCTION;
513 }
514 
515 void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
516   VisitNamedDecl(D);
517   // FIXME: convert to LazyStmtPtr?
518   // Unlike C/C++, method bodies will never be in header files.
519   bool HasBodyStuff = D->getBody() != nullptr     ||
520                       D->getSelfDecl() != nullptr || D->getCmdDecl() != nullptr;
521   Record.push_back(HasBodyStuff);
522   if (HasBodyStuff) {
523     Writer.AddStmt(D->getBody());
524     Writer.AddDeclRef(D->getSelfDecl(), Record);
525     Writer.AddDeclRef(D->getCmdDecl(), Record);
526   }
527   Record.push_back(D->isInstanceMethod());
528   Record.push_back(D->isVariadic());
529   Record.push_back(D->isPropertyAccessor());
530   Record.push_back(D->isDefined());
531   Record.push_back(D->IsOverriding);
532   Record.push_back(D->HasSkippedBody);
533 
534   Record.push_back(D->IsRedeclaration);
535   Record.push_back(D->HasRedeclaration);
536   if (D->HasRedeclaration) {
537     assert(Context.getObjCMethodRedeclaration(D));
538     Writer.AddDeclRef(Context.getObjCMethodRedeclaration(D), Record);
539   }
540 
541   // FIXME: stable encoding for @required/@optional
542   Record.push_back(D->getImplementationControl());
543   // FIXME: stable encoding for in/out/inout/bycopy/byref/oneway
544   Record.push_back(D->getObjCDeclQualifier());
545   Record.push_back(D->hasRelatedResultType());
546   Writer.AddTypeRef(D->getReturnType(), Record);
547   Writer.AddTypeSourceInfo(D->getReturnTypeSourceInfo(), Record);
548   Writer.AddSourceLocation(D->getLocEnd(), Record);
549   Record.push_back(D->param_size());
550   for (const auto *P : D->params())
551     Writer.AddDeclRef(P, Record);
552 
553   Record.push_back(D->SelLocsKind);
554   unsigned NumStoredSelLocs = D->getNumStoredSelLocs();
555   SourceLocation *SelLocs = D->getStoredSelLocs();
556   Record.push_back(NumStoredSelLocs);
557   for (unsigned i = 0; i != NumStoredSelLocs; ++i)
558     Writer.AddSourceLocation(SelLocs[i], Record);
559 
560   Code = serialization::DECL_OBJC_METHOD;
561 }
562 
563 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
564   VisitNamedDecl(D);
565   Writer.AddSourceLocation(D->getAtStartLoc(), Record);
566   Writer.AddSourceRange(D->getAtEndRange(), Record);
567   // Abstract class (no need to define a stable serialization::DECL code).
568 }
569 
570 void ASTDeclWriter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
571   VisitRedeclarable(D);
572   VisitObjCContainerDecl(D);
573   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
574 
575   Record.push_back(D->isThisDeclarationADefinition());
576   if (D->isThisDeclarationADefinition()) {
577     // Write the DefinitionData
578     ObjCInterfaceDecl::DefinitionData &Data = D->data();
579 
580     Writer.AddDeclRef(D->getSuperClass(), Record);
581     Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
582     Writer.AddSourceLocation(D->getEndOfDefinitionLoc(), Record);
583     Record.push_back(Data.HasDesignatedInitializers);
584 
585     // Write out the protocols that are directly referenced by the @interface.
586     Record.push_back(Data.ReferencedProtocols.size());
587     for (const auto *P : D->protocols())
588       Writer.AddDeclRef(P, Record);
589     for (const auto &PL : D->protocol_locs())
590       Writer.AddSourceLocation(PL, Record);
591 
592     // Write out the protocols that are transitively referenced.
593     Record.push_back(Data.AllReferencedProtocols.size());
594     for (ObjCList<ObjCProtocolDecl>::iterator
595               P = Data.AllReferencedProtocols.begin(),
596            PEnd = Data.AllReferencedProtocols.end();
597          P != PEnd; ++P)
598       Writer.AddDeclRef(*P, Record);
599 
600 
601     if (ObjCCategoryDecl *Cat = D->getCategoryListRaw()) {
602       // Ensure that we write out the set of categories for this class.
603       Writer.ObjCClassesWithCategories.insert(D);
604 
605       // Make sure that the categories get serialized.
606       for (; Cat; Cat = Cat->getNextClassCategoryRaw())
607         (void)Writer.GetDeclRef(Cat);
608     }
609   }
610 
611   Code = serialization::DECL_OBJC_INTERFACE;
612 }
613 
614 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
615   VisitFieldDecl(D);
616   // FIXME: stable encoding for @public/@private/@protected/@package
617   Record.push_back(D->getAccessControl());
618   Record.push_back(D->getSynthesize());
619 
620   if (!D->hasAttrs() &&
621       !D->isImplicit() &&
622       !D->isUsed(false) &&
623       !D->isInvalidDecl() &&
624       !D->isReferenced() &&
625       !D->isModulePrivate() &&
626       !D->getBitWidth() &&
627       !D->hasExtInfo() &&
628       D->getDeclName())
629     AbbrevToUse = Writer.getDeclObjCIvarAbbrev();
630 
631   Code = serialization::DECL_OBJC_IVAR;
632 }
633 
634 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
635   VisitRedeclarable(D);
636   VisitObjCContainerDecl(D);
637 
638   Record.push_back(D->isThisDeclarationADefinition());
639   if (D->isThisDeclarationADefinition()) {
640     Record.push_back(D->protocol_size());
641     for (const auto *I : D->protocols())
642       Writer.AddDeclRef(I, Record);
643     for (const auto &PL : D->protocol_locs())
644       Writer.AddSourceLocation(PL, Record);
645   }
646 
647   Code = serialization::DECL_OBJC_PROTOCOL;
648 }
649 
650 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
651   VisitFieldDecl(D);
652   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
653 }
654 
655 void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
656   VisitObjCContainerDecl(D);
657   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
658   Writer.AddSourceLocation(D->getIvarLBraceLoc(), Record);
659   Writer.AddSourceLocation(D->getIvarRBraceLoc(), Record);
660   Writer.AddDeclRef(D->getClassInterface(), Record);
661   Record.push_back(D->protocol_size());
662   for (const auto *I : D->protocols())
663     Writer.AddDeclRef(I, Record);
664   for (const auto &PL : D->protocol_locs())
665     Writer.AddSourceLocation(PL, Record);
666   Code = serialization::DECL_OBJC_CATEGORY;
667 }
668 
669 void ASTDeclWriter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D) {
670   VisitNamedDecl(D);
671   Writer.AddDeclRef(D->getClassInterface(), Record);
672   Code = serialization::DECL_OBJC_COMPATIBLE_ALIAS;
673 }
674 
675 void ASTDeclWriter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
676   VisitNamedDecl(D);
677   Writer.AddSourceLocation(D->getAtLoc(), Record);
678   Writer.AddSourceLocation(D->getLParenLoc(), Record);
679   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
680   // FIXME: stable encoding
681   Record.push_back((unsigned)D->getPropertyAttributes());
682   Record.push_back((unsigned)D->getPropertyAttributesAsWritten());
683   // FIXME: stable encoding
684   Record.push_back((unsigned)D->getPropertyImplementation());
685   Writer.AddDeclarationName(D->getGetterName(), Record);
686   Writer.AddDeclarationName(D->getSetterName(), Record);
687   Writer.AddDeclRef(D->getGetterMethodDecl(), Record);
688   Writer.AddDeclRef(D->getSetterMethodDecl(), Record);
689   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
690   Code = serialization::DECL_OBJC_PROPERTY;
691 }
692 
693 void ASTDeclWriter::VisitObjCImplDecl(ObjCImplDecl *D) {
694   VisitObjCContainerDecl(D);
695   Writer.AddDeclRef(D->getClassInterface(), Record);
696   // Abstract class (no need to define a stable serialization::DECL code).
697 }
698 
699 void ASTDeclWriter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
700   VisitObjCImplDecl(D);
701   Writer.AddIdentifierRef(D->getIdentifier(), Record);
702   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
703   Code = serialization::DECL_OBJC_CATEGORY_IMPL;
704 }
705 
706 void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
707   VisitObjCImplDecl(D);
708   Writer.AddDeclRef(D->getSuperClass(), Record);
709   Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
710   Writer.AddSourceLocation(D->getIvarLBraceLoc(), Record);
711   Writer.AddSourceLocation(D->getIvarRBraceLoc(), Record);
712   Record.push_back(D->hasNonZeroConstructors());
713   Record.push_back(D->hasDestructors());
714   Writer.AddCXXCtorInitializers(D->IvarInitializers, D->NumIvarInitializers,
715                                 Record);
716   Code = serialization::DECL_OBJC_IMPLEMENTATION;
717 }
718 
719 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
720   VisitDecl(D);
721   Writer.AddSourceLocation(D->getLocStart(), Record);
722   Writer.AddDeclRef(D->getPropertyDecl(), Record);
723   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
724   Writer.AddSourceLocation(D->getPropertyIvarDeclLoc(), Record);
725   Writer.AddStmt(D->getGetterCXXConstructor());
726   Writer.AddStmt(D->getSetterCXXAssignment());
727   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
728 }
729 
730 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
731   VisitDeclaratorDecl(D);
732   Record.push_back(D->isMutable());
733   if (D->InitStorage.getInt() == FieldDecl::ISK_BitWidthOrNothing &&
734       D->InitStorage.getPointer() == nullptr) {
735     Record.push_back(0);
736   } else if (D->InitStorage.getInt() == FieldDecl::ISK_CapturedVLAType) {
737     Record.push_back(D->InitStorage.getInt() + 1);
738     Writer.AddTypeRef(
739         QualType(static_cast<Type *>(D->InitStorage.getPointer()), 0),
740         Record);
741   } else {
742     Record.push_back(D->InitStorage.getInt() + 1);
743     Writer.AddStmt(static_cast<Expr *>(D->InitStorage.getPointer()));
744   }
745   if (!D->getDeclName())
746     Writer.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D), Record);
747 
748   if (!D->hasAttrs() &&
749       !D->isImplicit() &&
750       !D->isUsed(false) &&
751       !D->isInvalidDecl() &&
752       !D->isReferenced() &&
753       !D->isTopLevelDeclInObjCContainer() &&
754       !D->isModulePrivate() &&
755       !D->getBitWidth() &&
756       !D->hasInClassInitializer() &&
757       !D->hasExtInfo() &&
758       !ObjCIvarDecl::classofKind(D->getKind()) &&
759       !ObjCAtDefsFieldDecl::classofKind(D->getKind()) &&
760       D->getDeclName())
761     AbbrevToUse = Writer.getDeclFieldAbbrev();
762 
763   Code = serialization::DECL_FIELD;
764 }
765 
766 void ASTDeclWriter::VisitMSPropertyDecl(MSPropertyDecl *D) {
767   VisitDeclaratorDecl(D);
768   Writer.AddIdentifierRef(D->getGetterId(), Record);
769   Writer.AddIdentifierRef(D->getSetterId(), Record);
770   Code = serialization::DECL_MS_PROPERTY;
771 }
772 
773 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
774   VisitValueDecl(D);
775   Record.push_back(D->getChainingSize());
776 
777   for (const auto *P : D->chain())
778     Writer.AddDeclRef(P, Record);
779   Code = serialization::DECL_INDIRECTFIELD;
780 }
781 
782 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
783   VisitRedeclarable(D);
784   VisitDeclaratorDecl(D);
785   Record.push_back(D->getStorageClass());
786   Record.push_back(D->getTSCSpec());
787   Record.push_back(D->getInitStyle());
788   Record.push_back(D->isExceptionVariable());
789   Record.push_back(D->isNRVOVariable());
790   Record.push_back(D->isCXXForRangeDecl());
791   Record.push_back(D->isARCPseudoStrong());
792   Record.push_back(D->isConstexpr());
793   Record.push_back(D->isInitCapture());
794   Record.push_back(D->isPreviousDeclInSameBlockScope());
795   Record.push_back(D->getLinkageInternal());
796 
797   if (D->getInit()) {
798     Record.push_back(!D->isInitKnownICE() ? 1 : (D->isInitICE() ? 3 : 2));
799     Writer.AddStmt(D->getInit());
800   } else {
801     Record.push_back(0);
802   }
803 
804   enum {
805     VarNotTemplate = 0, VarTemplate, StaticDataMemberSpecialization
806   };
807   if (VarTemplateDecl *TemplD = D->getDescribedVarTemplate()) {
808     Record.push_back(VarTemplate);
809     Writer.AddDeclRef(TemplD, Record);
810   } else if (MemberSpecializationInfo *SpecInfo
811                = D->getMemberSpecializationInfo()) {
812     Record.push_back(StaticDataMemberSpecialization);
813     Writer.AddDeclRef(SpecInfo->getInstantiatedFrom(), Record);
814     Record.push_back(SpecInfo->getTemplateSpecializationKind());
815     Writer.AddSourceLocation(SpecInfo->getPointOfInstantiation(), Record);
816   } else {
817     Record.push_back(VarNotTemplate);
818   }
819 
820   if (!D->hasAttrs() &&
821       !D->isImplicit() &&
822       !D->isUsed(false) &&
823       !D->isInvalidDecl() &&
824       !D->isReferenced() &&
825       !D->isTopLevelDeclInObjCContainer() &&
826       D->getAccess() == AS_none &&
827       !D->isModulePrivate() &&
828       !needsAnonymousDeclarationNumber(D) &&
829       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
830       !D->hasExtInfo() &&
831       D->getFirstDecl() == D->getMostRecentDecl() &&
832       D->getInitStyle() == VarDecl::CInit &&
833       D->getInit() == nullptr &&
834       !isa<ParmVarDecl>(D) &&
835       !isa<VarTemplateSpecializationDecl>(D) &&
836       !D->isConstexpr() &&
837       !D->isInitCapture() &&
838       !D->isPreviousDeclInSameBlockScope() &&
839       !D->getMemberSpecializationInfo())
840     AbbrevToUse = Writer.getDeclVarAbbrev();
841 
842   Code = serialization::DECL_VAR;
843 }
844 
845 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
846   VisitVarDecl(D);
847   Code = serialization::DECL_IMPLICIT_PARAM;
848 }
849 
850 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
851   VisitVarDecl(D);
852   Record.push_back(D->isObjCMethodParameter());
853   Record.push_back(D->getFunctionScopeDepth());
854   Record.push_back(D->getFunctionScopeIndex());
855   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
856   Record.push_back(D->isKNRPromoted());
857   Record.push_back(D->hasInheritedDefaultArg());
858   Record.push_back(D->hasUninstantiatedDefaultArg());
859   if (D->hasUninstantiatedDefaultArg())
860     Writer.AddStmt(D->getUninstantiatedDefaultArg());
861   Code = serialization::DECL_PARM_VAR;
862 
863   assert(!D->isARCPseudoStrong()); // can be true of ImplicitParamDecl
864 
865   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
866   // we dynamically check for the properties that we optimize for, but don't
867   // know are true of all PARM_VAR_DECLs.
868   if (!D->hasAttrs() &&
869       !D->hasExtInfo() &&
870       !D->isImplicit() &&
871       !D->isUsed(false) &&
872       !D->isInvalidDecl() &&
873       !D->isReferenced() &&
874       D->getAccess() == AS_none &&
875       !D->isModulePrivate() &&
876       D->getStorageClass() == 0 &&
877       D->getInitStyle() == VarDecl::CInit && // Can params have anything else?
878       D->getFunctionScopeDepth() == 0 &&
879       D->getObjCDeclQualifier() == 0 &&
880       !D->isKNRPromoted() &&
881       !D->hasInheritedDefaultArg() &&
882       D->getInit() == nullptr &&
883       !D->hasUninstantiatedDefaultArg())  // No default expr.
884     AbbrevToUse = Writer.getDeclParmVarAbbrev();
885 
886   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
887   // just us assuming it.
888   assert(!D->getTSCSpec() && "PARM_VAR_DECL can't use TLS");
889   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
890   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
891   assert(D->getPreviousDecl() == nullptr && "PARM_VAR_DECL can't be redecl");
892   assert(!D->isStaticDataMember() &&
893          "PARM_VAR_DECL can't be static data member");
894 }
895 
896 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
897   VisitDecl(D);
898   Writer.AddStmt(D->getAsmString());
899   Writer.AddSourceLocation(D->getRParenLoc(), Record);
900   Code = serialization::DECL_FILE_SCOPE_ASM;
901 }
902 
903 void ASTDeclWriter::VisitEmptyDecl(EmptyDecl *D) {
904   VisitDecl(D);
905   Code = serialization::DECL_EMPTY;
906 }
907 
908 void ASTDeclWriter::VisitBlockDecl(BlockDecl *D) {
909   VisitDecl(D);
910   Writer.AddStmt(D->getBody());
911   Writer.AddTypeSourceInfo(D->getSignatureAsWritten(), Record);
912   Record.push_back(D->param_size());
913   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
914        P != PEnd; ++P)
915     Writer.AddDeclRef(*P, Record);
916   Record.push_back(D->isVariadic());
917   Record.push_back(D->blockMissingReturnType());
918   Record.push_back(D->isConversionFromLambda());
919   Record.push_back(D->capturesCXXThis());
920   Record.push_back(D->getNumCaptures());
921   for (const auto &capture : D->captures()) {
922     Writer.AddDeclRef(capture.getVariable(), Record);
923 
924     unsigned flags = 0;
925     if (capture.isByRef()) flags |= 1;
926     if (capture.isNested()) flags |= 2;
927     if (capture.hasCopyExpr()) flags |= 4;
928     Record.push_back(flags);
929 
930     if (capture.hasCopyExpr()) Writer.AddStmt(capture.getCopyExpr());
931   }
932 
933   Code = serialization::DECL_BLOCK;
934 }
935 
936 void ASTDeclWriter::VisitCapturedDecl(CapturedDecl *CD) {
937   Record.push_back(CD->getNumParams());
938   VisitDecl(CD);
939   Record.push_back(CD->getContextParamPosition());
940   Record.push_back(CD->isNothrow() ? 1 : 0);
941   // Body is stored by VisitCapturedStmt.
942   for (unsigned I = 0; I < CD->getNumParams(); ++I)
943     Writer.AddDeclRef(CD->getParam(I), Record);
944   Code = serialization::DECL_CAPTURED;
945 }
946 
947 void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
948   VisitDecl(D);
949   Record.push_back(D->getLanguage());
950   Writer.AddSourceLocation(D->getExternLoc(), Record);
951   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
952   Code = serialization::DECL_LINKAGE_SPEC;
953 }
954 
955 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
956   VisitNamedDecl(D);
957   Writer.AddSourceLocation(D->getLocStart(), Record);
958   Code = serialization::DECL_LABEL;
959 }
960 
961 
962 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
963   VisitRedeclarable(D);
964   VisitNamedDecl(D);
965   Record.push_back(D->isInline());
966   Writer.AddSourceLocation(D->getLocStart(), Record);
967   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
968 
969   if (D->isOriginalNamespace())
970     Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
971   Code = serialization::DECL_NAMESPACE;
972 
973   if (Writer.hasChain() && !D->isOriginalNamespace() &&
974       D->getOriginalNamespace()->isFromASTFile()) {
975     NamespaceDecl *NS = D->getOriginalNamespace();
976     Writer.AddUpdatedDeclContext(NS);
977 
978     // Make sure all visible decls are written. They will be recorded later.
979     if (StoredDeclsMap *Map = NS->buildLookup()) {
980       for (StoredDeclsMap::iterator D = Map->begin(), DEnd = Map->end();
981            D != DEnd; ++D) {
982         DeclContext::lookup_result R = D->second.getLookupResult();
983         for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E;
984              ++I)
985           Writer.GetDeclRef(*I);
986       }
987     }
988   }
989 
990   if (Writer.hasChain() && D->isAnonymousNamespace() &&
991       D == D->getMostRecentDecl()) {
992     // This is a most recent reopening of the anonymous namespace. If its parent
993     // is in a previous PCH (or is the TU), mark that parent for update, because
994     // the original namespace always points to the latest re-opening of its
995     // anonymous namespace.
996     Decl *Parent = cast<Decl>(
997         D->getParent()->getRedeclContext()->getPrimaryContext());
998     if (Parent->isFromASTFile() || isa<TranslationUnitDecl>(Parent)) {
999       Writer.DeclUpdates[Parent].push_back(
1000           ASTWriter::DeclUpdate(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE, D));
1001     }
1002   }
1003 }
1004 
1005 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
1006   VisitRedeclarable(D);
1007   VisitNamedDecl(D);
1008   Writer.AddSourceLocation(D->getNamespaceLoc(), Record);
1009   Writer.AddSourceLocation(D->getTargetNameLoc(), Record);
1010   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
1011   Writer.AddDeclRef(D->getNamespace(), Record);
1012   Code = serialization::DECL_NAMESPACE_ALIAS;
1013 }
1014 
1015 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
1016   VisitNamedDecl(D);
1017   Writer.AddSourceLocation(D->getUsingLoc(), Record);
1018   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
1019   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
1020   Writer.AddDeclRef(D->FirstUsingShadow.getPointer(), Record);
1021   Record.push_back(D->hasTypename());
1022   Writer.AddDeclRef(Context.getInstantiatedFromUsingDecl(D), Record);
1023   Code = serialization::DECL_USING;
1024 }
1025 
1026 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
1027   VisitRedeclarable(D);
1028   VisitNamedDecl(D);
1029   Writer.AddDeclRef(D->getTargetDecl(), Record);
1030   Writer.AddDeclRef(D->UsingOrNextShadow, Record);
1031   Writer.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D), Record);
1032   Code = serialization::DECL_USING_SHADOW;
1033 }
1034 
1035 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
1036   VisitNamedDecl(D);
1037   Writer.AddSourceLocation(D->getUsingLoc(), Record);
1038   Writer.AddSourceLocation(D->getNamespaceKeyLocation(), Record);
1039   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
1040   Writer.AddDeclRef(D->getNominatedNamespace(), Record);
1041   Writer.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()), Record);
1042   Code = serialization::DECL_USING_DIRECTIVE;
1043 }
1044 
1045 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
1046   VisitValueDecl(D);
1047   Writer.AddSourceLocation(D->getUsingLoc(), Record);
1048   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
1049   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
1050   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
1051 }
1052 
1053 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
1054                                                UnresolvedUsingTypenameDecl *D) {
1055   VisitTypeDecl(D);
1056   Writer.AddSourceLocation(D->getTypenameLoc(), Record);
1057   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
1058   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
1059 }
1060 
1061 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
1062   VisitRecordDecl(D);
1063 
1064   enum {
1065     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
1066   };
1067   if (ClassTemplateDecl *TemplD = D->getDescribedClassTemplate()) {
1068     Record.push_back(CXXRecTemplate);
1069     Writer.AddDeclRef(TemplD, Record);
1070   } else if (MemberSpecializationInfo *MSInfo
1071                = D->getMemberSpecializationInfo()) {
1072     Record.push_back(CXXRecMemberSpecialization);
1073     Writer.AddDeclRef(MSInfo->getInstantiatedFrom(), Record);
1074     Record.push_back(MSInfo->getTemplateSpecializationKind());
1075     Writer.AddSourceLocation(MSInfo->getPointOfInstantiation(), Record);
1076   } else {
1077     Record.push_back(CXXRecNotTemplate);
1078   }
1079 
1080   Record.push_back(D->isThisDeclarationADefinition());
1081   if (D->isThisDeclarationADefinition())
1082     Writer.AddCXXDefinitionData(D, Record);
1083 
1084   // Store (what we currently believe to be) the key function to avoid
1085   // deserializing every method so we can compute it.
1086   if (D->IsCompleteDefinition)
1087     Writer.AddDeclRef(Context.getCurrentKeyFunction(D), Record);
1088 
1089   Code = serialization::DECL_CXX_RECORD;
1090 }
1091 
1092 void ASTDeclWriter::VisitCXXMethodDecl(CXXMethodDecl *D) {
1093   VisitFunctionDecl(D);
1094   if (D->isCanonicalDecl()) {
1095     Record.push_back(D->size_overridden_methods());
1096     for (CXXMethodDecl::method_iterator
1097            I = D->begin_overridden_methods(), E = D->end_overridden_methods();
1098            I != E; ++I)
1099       Writer.AddDeclRef(*I, Record);
1100   } else {
1101     // We only need to record overridden methods once for the canonical decl.
1102     Record.push_back(0);
1103   }
1104 
1105   if (D->getFirstDecl() == D->getMostRecentDecl() &&
1106       !D->isInvalidDecl() &&
1107       !D->hasAttrs() &&
1108       !D->isTopLevelDeclInObjCContainer() &&
1109       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
1110       !D->hasExtInfo() &&
1111       !D->hasInheritedPrototype() &&
1112       D->hasWrittenPrototype())
1113     AbbrevToUse = Writer.getDeclCXXMethodAbbrev();
1114 
1115   Code = serialization::DECL_CXX_METHOD;
1116 }
1117 
1118 void ASTDeclWriter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
1119   VisitCXXMethodDecl(D);
1120 
1121   Writer.AddDeclRef(D->getInheritedConstructor(), Record);
1122   Record.push_back(D->IsExplicitSpecified);
1123   Writer.AddCXXCtorInitializers(D->CtorInitializers, D->NumCtorInitializers,
1124                                 Record);
1125 
1126   Code = serialization::DECL_CXX_CONSTRUCTOR;
1127 }
1128 
1129 void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
1130   VisitCXXMethodDecl(D);
1131 
1132   Writer.AddDeclRef(D->OperatorDelete, Record);
1133 
1134   Code = serialization::DECL_CXX_DESTRUCTOR;
1135 }
1136 
1137 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
1138   VisitCXXMethodDecl(D);
1139   Record.push_back(D->IsExplicitSpecified);
1140   Code = serialization::DECL_CXX_CONVERSION;
1141 }
1142 
1143 void ASTDeclWriter::VisitImportDecl(ImportDecl *D) {
1144   VisitDecl(D);
1145   Record.push_back(Writer.getSubmoduleID(D->getImportedModule()));
1146   ArrayRef<SourceLocation> IdentifierLocs = D->getIdentifierLocs();
1147   Record.push_back(!IdentifierLocs.empty());
1148   if (IdentifierLocs.empty()) {
1149     Writer.AddSourceLocation(D->getLocEnd(), Record);
1150     Record.push_back(1);
1151   } else {
1152     for (unsigned I = 0, N = IdentifierLocs.size(); I != N; ++I)
1153       Writer.AddSourceLocation(IdentifierLocs[I], Record);
1154     Record.push_back(IdentifierLocs.size());
1155   }
1156   // Note: the number of source locations must always be the last element in
1157   // the record.
1158   Code = serialization::DECL_IMPORT;
1159 }
1160 
1161 void ASTDeclWriter::VisitAccessSpecDecl(AccessSpecDecl *D) {
1162   VisitDecl(D);
1163   Writer.AddSourceLocation(D->getColonLoc(), Record);
1164   Code = serialization::DECL_ACCESS_SPEC;
1165 }
1166 
1167 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
1168   // Record the number of friend type template parameter lists here
1169   // so as to simplify memory allocation during deserialization.
1170   Record.push_back(D->NumTPLists);
1171   VisitDecl(D);
1172   bool hasFriendDecl = D->Friend.is<NamedDecl*>();
1173   Record.push_back(hasFriendDecl);
1174   if (hasFriendDecl)
1175     Writer.AddDeclRef(D->getFriendDecl(), Record);
1176   else
1177     Writer.AddTypeSourceInfo(D->getFriendType(), Record);
1178   for (unsigned i = 0; i < D->NumTPLists; ++i)
1179     Writer.AddTemplateParameterList(D->getFriendTypeTemplateParameterList(i),
1180                                     Record);
1181   Writer.AddDeclRef(D->getNextFriend(), Record);
1182   Record.push_back(D->UnsupportedFriend);
1183   Writer.AddSourceLocation(D->FriendLoc, Record);
1184   Code = serialization::DECL_FRIEND;
1185 }
1186 
1187 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
1188   VisitDecl(D);
1189   Record.push_back(D->getNumTemplateParameters());
1190   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
1191     Writer.AddTemplateParameterList(D->getTemplateParameterList(i), Record);
1192   Record.push_back(D->getFriendDecl() != nullptr);
1193   if (D->getFriendDecl())
1194     Writer.AddDeclRef(D->getFriendDecl(), Record);
1195   else
1196     Writer.AddTypeSourceInfo(D->getFriendType(), Record);
1197   Writer.AddSourceLocation(D->getFriendLoc(), Record);
1198   Code = serialization::DECL_FRIEND_TEMPLATE;
1199 }
1200 
1201 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
1202   VisitNamedDecl(D);
1203 
1204   Writer.AddDeclRef(D->getTemplatedDecl(), Record);
1205   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1206 }
1207 
1208 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
1209   VisitRedeclarable(D);
1210 
1211   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
1212   // getCommonPtr() can be used while this is still initializing.
1213   if (D->isFirstDecl()) {
1214     // This declaration owns the 'common' pointer, so serialize that data now.
1215     Writer.AddDeclRef(D->getInstantiatedFromMemberTemplate(), Record);
1216     if (D->getInstantiatedFromMemberTemplate())
1217       Record.push_back(D->isMemberSpecialization());
1218   }
1219 
1220   VisitTemplateDecl(D);
1221   Record.push_back(D->getIdentifierNamespace());
1222 }
1223 
1224 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1225   VisitRedeclarableTemplateDecl(D);
1226 
1227   if (D->isFirstDecl())
1228     AddTemplateSpecializations(D);
1229   Code = serialization::DECL_CLASS_TEMPLATE;
1230 }
1231 
1232 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
1233                                            ClassTemplateSpecializationDecl *D) {
1234   VisitCXXRecordDecl(D);
1235 
1236   llvm::PointerUnion<ClassTemplateDecl *,
1237                      ClassTemplatePartialSpecializationDecl *> InstFrom
1238     = D->getSpecializedTemplateOrPartial();
1239   if (Decl *InstFromD = InstFrom.dyn_cast<ClassTemplateDecl *>()) {
1240     Writer.AddDeclRef(InstFromD, Record);
1241   } else {
1242     Writer.AddDeclRef(InstFrom.get<ClassTemplatePartialSpecializationDecl *>(),
1243                       Record);
1244     Writer.AddTemplateArgumentList(&D->getTemplateInstantiationArgs(), Record);
1245   }
1246 
1247   Writer.AddTemplateArgumentList(&D->getTemplateArgs(), Record);
1248   Writer.AddSourceLocation(D->getPointOfInstantiation(), Record);
1249   Record.push_back(D->getSpecializationKind());
1250   Record.push_back(D->isCanonicalDecl());
1251 
1252   if (D->isCanonicalDecl()) {
1253     // When reading, we'll add it to the folding set of the following template.
1254     Writer.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl(), Record);
1255   }
1256 
1257   // Explicit info.
1258   Writer.AddTypeSourceInfo(D->getTypeAsWritten(), Record);
1259   if (D->getTypeAsWritten()) {
1260     Writer.AddSourceLocation(D->getExternLoc(), Record);
1261     Writer.AddSourceLocation(D->getTemplateKeywordLoc(), Record);
1262   }
1263 
1264   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
1265 }
1266 
1267 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
1268                                     ClassTemplatePartialSpecializationDecl *D) {
1269   VisitClassTemplateSpecializationDecl(D);
1270 
1271   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1272   Writer.AddASTTemplateArgumentListInfo(D->getTemplateArgsAsWritten(), Record);
1273 
1274   // These are read/set from/to the first declaration.
1275   if (D->getPreviousDecl() == nullptr) {
1276     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
1277     Record.push_back(D->isMemberSpecialization());
1278   }
1279 
1280   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
1281 }
1282 
1283 void ASTDeclWriter::VisitVarTemplateDecl(VarTemplateDecl *D) {
1284   VisitRedeclarableTemplateDecl(D);
1285 
1286   if (D->isFirstDecl())
1287     AddTemplateSpecializations(D);
1288   Code = serialization::DECL_VAR_TEMPLATE;
1289 }
1290 
1291 void ASTDeclWriter::VisitVarTemplateSpecializationDecl(
1292     VarTemplateSpecializationDecl *D) {
1293   VisitVarDecl(D);
1294 
1295   llvm::PointerUnion<VarTemplateDecl *, VarTemplatePartialSpecializationDecl *>
1296   InstFrom = D->getSpecializedTemplateOrPartial();
1297   if (Decl *InstFromD = InstFrom.dyn_cast<VarTemplateDecl *>()) {
1298     Writer.AddDeclRef(InstFromD, Record);
1299   } else {
1300     Writer.AddDeclRef(InstFrom.get<VarTemplatePartialSpecializationDecl *>(),
1301                       Record);
1302     Writer.AddTemplateArgumentList(&D->getTemplateInstantiationArgs(), Record);
1303   }
1304 
1305   // Explicit info.
1306   Writer.AddTypeSourceInfo(D->getTypeAsWritten(), Record);
1307   if (D->getTypeAsWritten()) {
1308     Writer.AddSourceLocation(D->getExternLoc(), Record);
1309     Writer.AddSourceLocation(D->getTemplateKeywordLoc(), Record);
1310   }
1311 
1312   Writer.AddTemplateArgumentList(&D->getTemplateArgs(), Record);
1313   Writer.AddSourceLocation(D->getPointOfInstantiation(), Record);
1314   Record.push_back(D->getSpecializationKind());
1315   Record.push_back(D->isCanonicalDecl());
1316 
1317   if (D->isCanonicalDecl()) {
1318     // When reading, we'll add it to the folding set of the following template.
1319     Writer.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl(), Record);
1320   }
1321 
1322   Code = serialization::DECL_VAR_TEMPLATE_SPECIALIZATION;
1323 }
1324 
1325 void ASTDeclWriter::VisitVarTemplatePartialSpecializationDecl(
1326     VarTemplatePartialSpecializationDecl *D) {
1327   VisitVarTemplateSpecializationDecl(D);
1328 
1329   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1330   Writer.AddASTTemplateArgumentListInfo(D->getTemplateArgsAsWritten(), Record);
1331 
1332   // These are read/set from/to the first declaration.
1333   if (D->getPreviousDecl() == nullptr) {
1334     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
1335     Record.push_back(D->isMemberSpecialization());
1336   }
1337 
1338   Code = serialization::DECL_VAR_TEMPLATE_PARTIAL_SPECIALIZATION;
1339 }
1340 
1341 void ASTDeclWriter::VisitClassScopeFunctionSpecializationDecl(
1342                                     ClassScopeFunctionSpecializationDecl *D) {
1343   VisitDecl(D);
1344   Writer.AddDeclRef(D->getSpecialization(), Record);
1345   Code = serialization::DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION;
1346 }
1347 
1348 
1349 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1350   VisitRedeclarableTemplateDecl(D);
1351 
1352   if (D->isFirstDecl())
1353     AddTemplateSpecializations(D);
1354   Code = serialization::DECL_FUNCTION_TEMPLATE;
1355 }
1356 
1357 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1358   VisitTypeDecl(D);
1359 
1360   Record.push_back(D->wasDeclaredWithTypename());
1361   Record.push_back(D->defaultArgumentWasInherited());
1362   Writer.AddTypeSourceInfo(D->getDefaultArgumentInfo(), Record);
1363 
1364   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1365 }
1366 
1367 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1368   // For an expanded parameter pack, record the number of expansion types here
1369   // so that it's easier for deserialization to allocate the right amount of
1370   // memory.
1371   if (D->isExpandedParameterPack())
1372     Record.push_back(D->getNumExpansionTypes());
1373 
1374   VisitDeclaratorDecl(D);
1375   // TemplateParmPosition.
1376   Record.push_back(D->getDepth());
1377   Record.push_back(D->getPosition());
1378 
1379   if (D->isExpandedParameterPack()) {
1380     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1381       Writer.AddTypeRef(D->getExpansionType(I), Record);
1382       Writer.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I), Record);
1383     }
1384 
1385     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1386   } else {
1387     // Rest of NonTypeTemplateParmDecl.
1388     Record.push_back(D->isParameterPack());
1389     Record.push_back(D->getDefaultArgument() != nullptr);
1390     if (D->getDefaultArgument()) {
1391       Writer.AddStmt(D->getDefaultArgument());
1392       Record.push_back(D->defaultArgumentWasInherited());
1393     }
1394     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1395   }
1396 }
1397 
1398 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1399   // For an expanded parameter pack, record the number of expansion types here
1400   // so that it's easier for deserialization to allocate the right amount of
1401   // memory.
1402   if (D->isExpandedParameterPack())
1403     Record.push_back(D->getNumExpansionTemplateParameters());
1404 
1405   VisitTemplateDecl(D);
1406   // TemplateParmPosition.
1407   Record.push_back(D->getDepth());
1408   Record.push_back(D->getPosition());
1409 
1410   if (D->isExpandedParameterPack()) {
1411     for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
1412          I != N; ++I)
1413       Writer.AddTemplateParameterList(D->getExpansionTemplateParameters(I),
1414                                       Record);
1415     Code = serialization::DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK;
1416   } else {
1417     // Rest of TemplateTemplateParmDecl.
1418     Writer.AddTemplateArgumentLoc(D->getDefaultArgument(), Record);
1419     Record.push_back(D->defaultArgumentWasInherited());
1420     Record.push_back(D->isParameterPack());
1421     Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1422   }
1423 }
1424 
1425 void ASTDeclWriter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
1426   VisitRedeclarableTemplateDecl(D);
1427   Code = serialization::DECL_TYPE_ALIAS_TEMPLATE;
1428 }
1429 
1430 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1431   VisitDecl(D);
1432   Writer.AddStmt(D->getAssertExpr());
1433   Record.push_back(D->isFailed());
1434   Writer.AddStmt(D->getMessage());
1435   Writer.AddSourceLocation(D->getRParenLoc(), Record);
1436   Code = serialization::DECL_STATIC_ASSERT;
1437 }
1438 
1439 /// \brief Emit the DeclContext part of a declaration context decl.
1440 ///
1441 /// \param LexicalOffset the offset at which the DECL_CONTEXT_LEXICAL
1442 /// block for this declaration context is stored. May be 0 to indicate
1443 /// that there are no declarations stored within this context.
1444 ///
1445 /// \param VisibleOffset the offset at which the DECL_CONTEXT_VISIBLE
1446 /// block for this declaration context is stored. May be 0 to indicate
1447 /// that there are no declarations visible from this context. Note
1448 /// that this value will not be emitted for non-primary declaration
1449 /// contexts.
1450 void ASTDeclWriter::VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
1451                                      uint64_t VisibleOffset) {
1452   Record.push_back(LexicalOffset);
1453   Record.push_back(VisibleOffset);
1454 }
1455 
1456 template <typename T>
1457 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1458   T *First = D->getFirstDecl();
1459   T *MostRecent = First->getMostRecentDecl();
1460   if (MostRecent != First) {
1461     assert(isRedeclarableDeclKind(static_cast<T *>(D)->getKind()) &&
1462            "Not considered redeclarable?");
1463 
1464     auto *Previous = D->getPreviousDecl();
1465     auto *FirstToEmit = First;
1466     if (Context.getLangOpts().Modules && Writer.Chain && !Previous) {
1467       // In a modules build, we can have imported declarations after a local
1468       // canonical declaration. If we do, we want to treat the first imported
1469       // declaration as our canonical declaration on reload, in order to
1470       // rebuild the redecl chain in the right order.
1471       for (auto *Redecl = MostRecent; Redecl;
1472            Redecl = Redecl->getPreviousDecl())
1473         if (Redecl->isFromASTFile())
1474           FirstToEmit = Redecl;
1475     }
1476 
1477     // There is more than one declaration of this entity, so we will need to
1478     // write a redeclaration chain.
1479     Writer.AddDeclRef(FirstToEmit, Record);
1480     Record.push_back(FirstToEmit != First);
1481     Writer.Redeclarations.insert(First);
1482 
1483     // Make sure that we serialize both the previous and the most-recent
1484     // declarations, which (transitively) ensures that all declarations in the
1485     // chain get serialized.
1486     //
1487     // FIXME: This is not correct; when we reach an imported declaration we
1488     // won't emit its previous declaration.
1489     (void)Writer.GetDeclRef(Previous);
1490     (void)Writer.GetDeclRef(MostRecent);
1491   } else {
1492     // We use the sentinel value 0 to indicate an only declaration.
1493     Record.push_back(0);
1494   }
1495 }
1496 
1497 void ASTDeclWriter::VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D) {
1498   Record.push_back(D->varlist_size());
1499   VisitDecl(D);
1500   for (auto *I : D->varlists())
1501     Writer.AddStmt(I);
1502   Code = serialization::DECL_OMP_THREADPRIVATE;
1503 }
1504 
1505 //===----------------------------------------------------------------------===//
1506 // ASTWriter Implementation
1507 //===----------------------------------------------------------------------===//
1508 
1509 void ASTWriter::WriteDeclAbbrevs() {
1510   using namespace llvm;
1511 
1512   BitCodeAbbrev *Abv;
1513 
1514   // Abbreviation for DECL_FIELD
1515   Abv = new BitCodeAbbrev();
1516   Abv->Add(BitCodeAbbrevOp(serialization::DECL_FIELD));
1517   // Decl
1518   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1519   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1520   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1521   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1522   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1523   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1524   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1525   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1526   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1527   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1528   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1529   // NamedDecl
1530   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1531   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1532   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1533   // ValueDecl
1534   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1535   // DeclaratorDecl
1536   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1537   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1538   // FieldDecl
1539   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1540   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1541   // Type Source Info
1542   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1543   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1544   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1545   DeclFieldAbbrev = Stream.EmitAbbrev(Abv);
1546 
1547   // Abbreviation for DECL_OBJC_IVAR
1548   Abv = new BitCodeAbbrev();
1549   Abv->Add(BitCodeAbbrevOp(serialization::DECL_OBJC_IVAR));
1550   // Decl
1551   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1552   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1553   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1554   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1555   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1556   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1557   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1558   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1559   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1560   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1561   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1562   // NamedDecl
1563   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1564   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1565   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1566   // ValueDecl
1567   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1568   // DeclaratorDecl
1569   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1570   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1571   // FieldDecl
1572   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1573   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1574   // ObjC Ivar
1575   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getAccessControl
1576   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getSynthesize
1577   // Type Source Info
1578   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1579   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1580   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1581   DeclObjCIvarAbbrev = Stream.EmitAbbrev(Abv);
1582 
1583   // Abbreviation for DECL_ENUM
1584   Abv = new BitCodeAbbrev();
1585   Abv->Add(BitCodeAbbrevOp(serialization::DECL_ENUM));
1586   // Redeclarable
1587   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1588   // Decl
1589   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1590   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1591   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1592   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1593   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1594   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1595   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1596   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1597   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1598   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1599   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1600   // NamedDecl
1601   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1602   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1603   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1604   // TypeDecl
1605   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1606   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1607   // TagDecl
1608   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1609   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1610   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1611   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1612   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1613   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsCompleteDefinitionRequired
1614   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1615   Abv->Add(BitCodeAbbrevOp(0));                         // ExtInfoKind
1616   // EnumDecl
1617   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddTypeRef
1618   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IntegerType
1619   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getPromotionType
1620   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumPositiveBits
1621   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumNegativeBits
1622   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScoped
1623   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScopedUsingClassTag
1624   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isFixed
1625   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InstantiatedMembEnum
1626   // DC
1627   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1628   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1629   DeclEnumAbbrev = Stream.EmitAbbrev(Abv);
1630 
1631   // Abbreviation for DECL_RECORD
1632   Abv = new BitCodeAbbrev();
1633   Abv->Add(BitCodeAbbrevOp(serialization::DECL_RECORD));
1634   // Redeclarable
1635   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1636   // Decl
1637   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1638   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1639   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1640   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1641   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1642   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1643   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1644   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1645   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1646   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1647   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1648   // NamedDecl
1649   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1650   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1651   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1652   // TypeDecl
1653   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1654   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1655   // TagDecl
1656   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1657   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1658   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1659   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1660   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1661   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsCompleteDefinitionRequired
1662   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1663   Abv->Add(BitCodeAbbrevOp(0));                         // ExtInfoKind
1664   // RecordDecl
1665   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // FlexibleArrayMember
1666   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // AnonymousStructUnion
1667   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasObjectMember
1668   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasVolatileMember
1669   // DC
1670   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1671   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1672   DeclRecordAbbrev = Stream.EmitAbbrev(Abv);
1673 
1674   // Abbreviation for DECL_PARM_VAR
1675   Abv = new BitCodeAbbrev();
1676   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1677   // Redeclarable
1678   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1679   // Decl
1680   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1681   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1682   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1683   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1684   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1685   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1686   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1687   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1688   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1689   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1690   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1691   // NamedDecl
1692   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1693   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1694   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1695   // ValueDecl
1696   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1697   // DeclaratorDecl
1698   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1699   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1700   // VarDecl
1701   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClass
1702   Abv->Add(BitCodeAbbrevOp(0));                       // getTSCSpec
1703   Abv->Add(BitCodeAbbrevOp(0));                       // hasCXXDirectInitializer
1704   Abv->Add(BitCodeAbbrevOp(0));                       // isExceptionVariable
1705   Abv->Add(BitCodeAbbrevOp(0));                       // isNRVOVariable
1706   Abv->Add(BitCodeAbbrevOp(0));                       // isCXXForRangeDecl
1707   Abv->Add(BitCodeAbbrevOp(0));                       // isARCPseudoStrong
1708   Abv->Add(BitCodeAbbrevOp(0));                       // isConstexpr
1709   Abv->Add(BitCodeAbbrevOp(0));                       // isInitCapture
1710   Abv->Add(BitCodeAbbrevOp(0));                       // isPrevDeclInSameScope
1711   Abv->Add(BitCodeAbbrevOp(0));                       // Linkage
1712   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
1713   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
1714   // ParmVarDecl
1715   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsObjCMethodParameter
1716   Abv->Add(BitCodeAbbrevOp(0));                       // ScopeDepth
1717   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ScopeIndex
1718   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
1719   Abv->Add(BitCodeAbbrevOp(0));                       // KNRPromoted
1720   Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
1721   Abv->Add(BitCodeAbbrevOp(0));                   // HasUninstantiatedDefaultArg
1722   // Type Source Info
1723   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1724   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1725   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1726   DeclParmVarAbbrev = Stream.EmitAbbrev(Abv);
1727 
1728   // Abbreviation for DECL_TYPEDEF
1729   Abv = new BitCodeAbbrev();
1730   Abv->Add(BitCodeAbbrevOp(serialization::DECL_TYPEDEF));
1731   // Redeclarable
1732   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1733   // Decl
1734   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1735   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1736   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1737   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1738   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1739   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isUsed
1740   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isReferenced
1741   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1742   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // C++ AccessSpecifier
1743   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1744   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1745   // NamedDecl
1746   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1747   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1748   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1749   // TypeDecl
1750   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1751   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1752   // TypedefDecl
1753   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1754   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1755   DeclTypedefAbbrev = Stream.EmitAbbrev(Abv);
1756 
1757   // Abbreviation for DECL_VAR
1758   Abv = new BitCodeAbbrev();
1759   Abv->Add(BitCodeAbbrevOp(serialization::DECL_VAR));
1760   // Redeclarable
1761   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1762   // Decl
1763   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1764   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1765   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1766   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1767   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1768   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1769   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1770   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1771   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1772   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1773   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1774   // NamedDecl
1775   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1776   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1777   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1778   // ValueDecl
1779   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1780   // DeclaratorDecl
1781   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1782   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1783   // VarDecl
1784   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClass
1785   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // getTSCSpec
1786   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // CXXDirectInitializer
1787   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
1788   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
1789   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
1790   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
1791   Abv->Add(BitCodeAbbrevOp(0));                         // isConstexpr
1792   Abv->Add(BitCodeAbbrevOp(0));                         // isInitCapture
1793   Abv->Add(BitCodeAbbrevOp(0));                         // isPrevDeclInSameScope
1794   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Linkage
1795   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasInit
1796   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasMemberSpecInfo
1797   // Type Source Info
1798   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1799   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1800   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1801   DeclVarAbbrev = Stream.EmitAbbrev(Abv);
1802 
1803   // Abbreviation for DECL_CXX_METHOD
1804   Abv = new BitCodeAbbrev();
1805   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CXX_METHOD));
1806   // RedeclarableDecl
1807   Abv->Add(BitCodeAbbrevOp(0));                         // CanonicalDecl
1808   // Decl
1809   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // DeclContext
1810   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalDeclContext
1811   Abv->Add(BitCodeAbbrevOp(0));                         // Invalid
1812   Abv->Add(BitCodeAbbrevOp(0));                         // HasAttrs
1813   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Implicit
1814   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Used
1815   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Referenced
1816   Abv->Add(BitCodeAbbrevOp(0));                         // InObjCContainer
1817   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // Access
1818   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ModulePrivate
1819   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SubmoduleID
1820   // NamedDecl
1821   Abv->Add(BitCodeAbbrevOp(DeclarationName::Identifier)); // NameKind
1822   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Identifier
1823   Abv->Add(BitCodeAbbrevOp(0));                         // AnonDeclNumber
1824   // ValueDecl
1825   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Type
1826   // DeclaratorDecl
1827   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InnerLocStart
1828   Abv->Add(BitCodeAbbrevOp(0));                         // HasExtInfo
1829   // FunctionDecl
1830   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 11)); // IDNS
1831   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // StorageClass
1832   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Inline
1833   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InlineSpecified
1834   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // VirtualAsWritten
1835   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Pure
1836   Abv->Add(BitCodeAbbrevOp(0));                         // HasInheritedProto
1837   Abv->Add(BitCodeAbbrevOp(1));                         // HasWrittenProto
1838   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Deleted
1839   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Trivial
1840   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Defaulted
1841   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ExplicitlyDefaulted
1842   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ImplicitReturnZero
1843   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Constexpr
1844   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // SkippedBody
1845   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // LateParsed
1846   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Linkage
1847   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LocEnd
1848   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // TemplateKind
1849   // This Array slurps the rest of the record. Fortunately we want to encode
1850   // (nearly) all the remaining (variable number of) fields in the same way.
1851   //
1852   // This is the function template information if any, then
1853   //         NumParams and Params[] from FunctionDecl, and
1854   //         NumOverriddenMethods, OverriddenMethods[] from CXXMethodDecl.
1855   //
1856   //  Add an AbbrevOp for 'size then elements' and use it here.
1857   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1858   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1859   DeclCXXMethodAbbrev = Stream.EmitAbbrev(Abv);
1860 
1861   // Abbreviation for EXPR_DECL_REF
1862   Abv = new BitCodeAbbrev();
1863   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_DECL_REF));
1864   //Stmt
1865   //Expr
1866   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1867   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1868   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1869   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1870   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1871   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1872   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1873   //DeclRefExpr
1874   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HasQualifier
1875   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //GetDeclFound
1876   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ExplicitTemplateArgs
1877   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HadMultipleCandidates
1878   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1879                            1)); // RefersToEnclosingVariableOrCapture
1880   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclRef
1881   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1882   DeclRefExprAbbrev = Stream.EmitAbbrev(Abv);
1883 
1884   // Abbreviation for EXPR_INTEGER_LITERAL
1885   Abv = new BitCodeAbbrev();
1886   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_INTEGER_LITERAL));
1887   //Stmt
1888   //Expr
1889   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1890   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1891   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1892   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1893   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1894   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1895   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1896   //Integer Literal
1897   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1898   Abv->Add(BitCodeAbbrevOp(32));                      // Bit Width
1899   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Value
1900   IntegerLiteralAbbrev = Stream.EmitAbbrev(Abv);
1901 
1902   // Abbreviation for EXPR_CHARACTER_LITERAL
1903   Abv = new BitCodeAbbrev();
1904   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_CHARACTER_LITERAL));
1905   //Stmt
1906   //Expr
1907   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1908   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1909   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1910   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1911   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1912   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1913   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1914   //Character Literal
1915   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getValue
1916   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1917   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // getKind
1918   CharacterLiteralAbbrev = Stream.EmitAbbrev(Abv);
1919 
1920   // Abbreviation for EXPR_IMPLICIT_CAST
1921   Abv = new BitCodeAbbrev();
1922   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_IMPLICIT_CAST));
1923   // Stmt
1924   // Expr
1925   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1926   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1927   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1928   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1929   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1930   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1931   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1932   // CastExpr
1933   Abv->Add(BitCodeAbbrevOp(0)); // PathSize
1934   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 6)); // CastKind
1935   // ImplicitCastExpr
1936   ExprImplicitCastAbbrev = Stream.EmitAbbrev(Abv);
1937 
1938   Abv = new BitCodeAbbrev();
1939   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
1940   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1941   DeclContextLexicalAbbrev = Stream.EmitAbbrev(Abv);
1942 
1943   Abv = new BitCodeAbbrev();
1944   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
1945   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1946   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1947   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(Abv);
1948 }
1949 
1950 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
1951 /// consumers of the AST.
1952 ///
1953 /// Such decls will always be deserialized from the AST file, so we would like
1954 /// this to be as restrictive as possible. Currently the predicate is driven by
1955 /// code generation requirements, if other clients have a different notion of
1956 /// what is "required" then we may have to consider an alternate scheme where
1957 /// clients can iterate over the top-level decls and get information on them,
1958 /// without necessary deserializing them. We could explicitly require such
1959 /// clients to use a separate API call to "realize" the decl. This should be
1960 /// relatively painless since they would presumably only do it for top-level
1961 /// decls.
1962 static bool isRequiredDecl(const Decl *D, ASTContext &Context) {
1963   // An ObjCMethodDecl is never considered as "required" because its
1964   // implementation container always is.
1965 
1966   // File scoped assembly or obj-c implementation must be seen. ImportDecl is
1967   // used by codegen to determine the set of imported modules to search for
1968   // inputs for automatic linking.
1969   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplDecl>(D) || isa<ImportDecl>(D))
1970     return true;
1971 
1972   return Context.DeclMustBeEmitted(D);
1973 }
1974 
1975 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
1976   // Switch case IDs are per Decl.
1977   ClearSwitchCaseIDs();
1978 
1979   RecordData Record;
1980   ASTDeclWriter W(*this, Context, Record);
1981 
1982   // Determine the ID for this declaration.
1983   serialization::DeclID ID;
1984   if (D->isFromASTFile()) {
1985     assert(isRewritten(D) && "should not be emitting imported decl");
1986     ID = getDeclID(D);
1987   } else {
1988     serialization::DeclID &IDR = DeclIDs[D];
1989     if (IDR == 0)
1990       IDR = NextDeclID++;
1991 
1992     ID= IDR;
1993   }
1994 
1995   bool isReplacingADecl = ID < FirstDeclID;
1996 
1997   // If this declaration is also a DeclContext, write blocks for the
1998   // declarations that lexically stored inside its context and those
1999   // declarations that are visible from its context. These blocks
2000   // are written before the declaration itself so that we can put
2001   // their offsets into the record for the declaration.
2002   uint64_t LexicalOffset = 0;
2003   uint64_t VisibleOffset = 0;
2004   DeclContext *DC = dyn_cast<DeclContext>(D);
2005   if (DC) {
2006     if (isReplacingADecl) {
2007       // It is replacing a decl from a chained PCH; make sure that the
2008       // DeclContext is fully loaded.
2009       if (DC->hasExternalLexicalStorage())
2010         DC->LoadLexicalDeclsFromExternalStorage();
2011       if (DC->hasExternalVisibleStorage())
2012         Chain->completeVisibleDeclsMap(DC);
2013     }
2014     LexicalOffset = WriteDeclContextLexicalBlock(Context, DC);
2015     VisibleOffset = WriteDeclContextVisibleBlock(Context, DC);
2016   }
2017 
2018   if (isReplacingADecl) {
2019     // We're replacing a decl in a previous file.
2020     ReplacedDecls.push_back(ReplacedDeclInfo(ID, Stream.GetCurrentBitNo(),
2021                                              D->getLocation()));
2022   } else {
2023     unsigned Index = ID - FirstDeclID;
2024 
2025     // Record the offset for this declaration
2026     SourceLocation Loc = D->getLocation();
2027     if (DeclOffsets.size() == Index)
2028       DeclOffsets.push_back(DeclOffset(Loc, Stream.GetCurrentBitNo()));
2029     else if (DeclOffsets.size() < Index) {
2030       DeclOffsets.resize(Index+1);
2031       DeclOffsets[Index].setLocation(Loc);
2032       DeclOffsets[Index].BitOffset = Stream.GetCurrentBitNo();
2033     }
2034 
2035     SourceManager &SM = Context.getSourceManager();
2036     if (Loc.isValid() && SM.isLocalSourceLocation(Loc))
2037       associateDeclWithFile(D, ID);
2038   }
2039 
2040   // Build and emit a record for this declaration
2041   Record.clear();
2042   W.Code = (serialization::DeclCode)0;
2043   W.AbbrevToUse = 0;
2044   W.Visit(D);
2045   if (DC) W.VisitDeclContext(DC, LexicalOffset, VisibleOffset);
2046 
2047   if (!W.Code)
2048     llvm::report_fatal_error(StringRef("unexpected declaration kind '") +
2049                             D->getDeclKindName() + "'");
2050   Stream.EmitRecord(W.Code, Record, W.AbbrevToUse);
2051 
2052   // Flush any expressions that were written as part of this declaration.
2053   FlushStmts();
2054 
2055   // Flush C++ base specifiers, if there are any.
2056   FlushCXXBaseSpecifiers();
2057 
2058   // Note declarations that should be deserialized eagerly so that we can add
2059   // them to a record in the AST file later.
2060   if (isRequiredDecl(D, Context))
2061     EagerlyDeserializedDecls.push_back(ID);
2062 }
2063 
2064 void ASTWriter::AddFunctionDefinition(const FunctionDecl *FD,
2065                                       RecordData &Record) {
2066   ClearSwitchCaseIDs();
2067 
2068   ASTDeclWriter W(*this, FD->getASTContext(), Record);
2069   W.AddFunctionDefinition(FD);
2070 }
2071