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 "ASTCommon.h"
15 #include "clang/AST/DeclCXX.h"
16 #include "clang/AST/DeclContextInternals.h"
17 #include "clang/AST/DeclTemplate.h"
18 #include "clang/AST/DeclVisitor.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/Basic/SourceManager.h"
21 #include "clang/Serialization/ASTReader.h"
22 #include "clang/Serialization/ASTWriter.h"
23 #include "llvm/Bitcode/BitstreamWriter.h"
24 #include "llvm/Support/ErrorHandling.h"
25 using namespace clang;
26 using namespace serialization;
27 
28 //===----------------------------------------------------------------------===//
29 // Declaration serialization
30 //===----------------------------------------------------------------------===//
31 
32 namespace clang {
33   class ASTDeclWriter : public DeclVisitor<ASTDeclWriter, void> {
34     ASTWriter &Writer;
35     ASTContext &Context;
36     ASTRecordWriter Record;
37 
38     serialization::DeclCode Code;
39     unsigned AbbrevToUse;
40 
41   public:
42     ASTDeclWriter(ASTWriter &Writer, ASTContext &Context,
43                   ASTWriter::RecordDataImpl &Record)
44         : Writer(Writer), Context(Context), Record(Writer, Record),
45           Code((serialization::DeclCode)0), AbbrevToUse(0) {}
46 
47     uint64_t Emit(Decl *D) {
48       if (!Code)
49         llvm::report_fatal_error(StringRef("unexpected declaration kind '") +
50             D->getDeclKindName() + "'");
51       return Record.Emit(Code, AbbrevToUse);
52     }
53 
54     void Visit(Decl *D);
55 
56     void VisitDecl(Decl *D);
57     void VisitPragmaCommentDecl(PragmaCommentDecl *D);
58     void VisitPragmaDetectMismatchDecl(PragmaDetectMismatchDecl *D);
59     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
60     void VisitNamedDecl(NamedDecl *D);
61     void VisitLabelDecl(LabelDecl *LD);
62     void VisitNamespaceDecl(NamespaceDecl *D);
63     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
64     void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
65     void VisitTypeDecl(TypeDecl *D);
66     void VisitTypedefNameDecl(TypedefNameDecl *D);
67     void VisitTypedefDecl(TypedefDecl *D);
68     void VisitTypeAliasDecl(TypeAliasDecl *D);
69     void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
70     void VisitTagDecl(TagDecl *D);
71     void VisitEnumDecl(EnumDecl *D);
72     void VisitRecordDecl(RecordDecl *D);
73     void VisitCXXRecordDecl(CXXRecordDecl *D);
74     void VisitClassTemplateSpecializationDecl(
75                                             ClassTemplateSpecializationDecl *D);
76     void VisitClassTemplatePartialSpecializationDecl(
77                                      ClassTemplatePartialSpecializationDecl *D);
78     void VisitVarTemplateSpecializationDecl(VarTemplateSpecializationDecl *D);
79     void VisitVarTemplatePartialSpecializationDecl(
80         VarTemplatePartialSpecializationDecl *D);
81     void VisitClassScopeFunctionSpecializationDecl(
82                                        ClassScopeFunctionSpecializationDecl *D);
83     void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
84     void VisitValueDecl(ValueDecl *D);
85     void VisitEnumConstantDecl(EnumConstantDecl *D);
86     void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
87     void VisitDeclaratorDecl(DeclaratorDecl *D);
88     void VisitFunctionDecl(FunctionDecl *D);
89     void VisitCXXMethodDecl(CXXMethodDecl *D);
90     void VisitCXXConstructorDecl(CXXConstructorDecl *D);
91     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
92     void VisitCXXConversionDecl(CXXConversionDecl *D);
93     void VisitFieldDecl(FieldDecl *D);
94     void VisitMSPropertyDecl(MSPropertyDecl *D);
95     void VisitIndirectFieldDecl(IndirectFieldDecl *D);
96     void VisitVarDecl(VarDecl *D);
97     void VisitImplicitParamDecl(ImplicitParamDecl *D);
98     void VisitParmVarDecl(ParmVarDecl *D);
99     void VisitDecompositionDecl(DecompositionDecl *D);
100     void VisitBindingDecl(BindingDecl *D);
101     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
102     void VisitTemplateDecl(TemplateDecl *D);
103     void VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
104     void VisitClassTemplateDecl(ClassTemplateDecl *D);
105     void VisitVarTemplateDecl(VarTemplateDecl *D);
106     void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
107     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
108     void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
109     void VisitUsingDecl(UsingDecl *D);
110     void VisitUsingPackDecl(UsingPackDecl *D);
111     void VisitUsingShadowDecl(UsingShadowDecl *D);
112     void VisitConstructorUsingShadowDecl(ConstructorUsingShadowDecl *D);
113     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
114     void VisitExportDecl(ExportDecl *D);
115     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
116     void VisitImportDecl(ImportDecl *D);
117     void VisitAccessSpecDecl(AccessSpecDecl *D);
118     void VisitFriendDecl(FriendDecl *D);
119     void VisitFriendTemplateDecl(FriendTemplateDecl *D);
120     void VisitStaticAssertDecl(StaticAssertDecl *D);
121     void VisitBlockDecl(BlockDecl *D);
122     void VisitCapturedDecl(CapturedDecl *D);
123     void VisitEmptyDecl(EmptyDecl *D);
124 
125     void VisitDeclContext(DeclContext *DC);
126     template <typename T> void VisitRedeclarable(Redeclarable<T> *D);
127 
128 
129     // FIXME: Put in the same order is DeclNodes.td?
130     void VisitObjCMethodDecl(ObjCMethodDecl *D);
131     void VisitObjCTypeParamDecl(ObjCTypeParamDecl *D);
132     void VisitObjCContainerDecl(ObjCContainerDecl *D);
133     void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
134     void VisitObjCIvarDecl(ObjCIvarDecl *D);
135     void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
136     void VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D);
137     void VisitObjCCategoryDecl(ObjCCategoryDecl *D);
138     void VisitObjCImplDecl(ObjCImplDecl *D);
139     void VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D);
140     void VisitObjCImplementationDecl(ObjCImplementationDecl *D);
141     void VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D);
142     void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
143     void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
144     void VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D);
145     void VisitOMPDeclareReductionDecl(OMPDeclareReductionDecl *D);
146     void VisitOMPCapturedExprDecl(OMPCapturedExprDecl *D);
147 
148     /// Add an Objective-C type parameter list to the given record.
149     void AddObjCTypeParamList(ObjCTypeParamList *typeParams) {
150       // Empty type parameter list.
151       if (!typeParams) {
152         Record.push_back(0);
153         return;
154       }
155 
156       Record.push_back(typeParams->size());
157       for (auto typeParam : *typeParams) {
158         Record.AddDeclRef(typeParam);
159       }
160       Record.AddSourceLocation(typeParams->getLAngleLoc());
161       Record.AddSourceLocation(typeParams->getRAngleLoc());
162     }
163 
164     /// Add to the record the first declaration from each module file that
165     /// provides a declaration of D. The intent is to provide a sufficient
166     /// set such that reloading this set will load all current redeclarations.
167     void AddFirstDeclFromEachModule(const Decl *D, bool IncludeLocal) {
168       llvm::MapVector<ModuleFile*, const Decl*> Firsts;
169       // FIXME: We can skip entries that we know are implied by others.
170       for (const Decl *R = D->getMostRecentDecl(); R; R = R->getPreviousDecl()) {
171         if (R->isFromASTFile())
172           Firsts[Writer.Chain->getOwningModuleFile(R)] = R;
173         else if (IncludeLocal)
174           Firsts[nullptr] = R;
175       }
176       for (const auto &F : Firsts)
177         Record.AddDeclRef(F.second);
178     }
179 
180     /// Get the specialization decl from an entry in the specialization list.
181     template <typename EntryType>
182     typename RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::DeclType *
183     getSpecializationDecl(EntryType &T) {
184       return RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::getDecl(&T);
185     }
186 
187     /// Get the list of partial specializations from a template's common ptr.
188     template<typename T>
189     decltype(T::PartialSpecializations) &getPartialSpecializations(T *Common) {
190       return Common->PartialSpecializations;
191     }
192     ArrayRef<Decl> getPartialSpecializations(FunctionTemplateDecl::Common *) {
193       return None;
194     }
195 
196     template<typename DeclTy>
197     void AddTemplateSpecializations(DeclTy *D) {
198       auto *Common = D->getCommonPtr();
199 
200       // If we have any lazy specializations, and the external AST source is
201       // our chained AST reader, we can just write out the DeclIDs. Otherwise,
202       // we need to resolve them to actual declarations.
203       if (Writer.Chain != Writer.Context->getExternalSource() &&
204           Common->LazySpecializations) {
205         D->LoadLazySpecializations();
206         assert(!Common->LazySpecializations);
207       }
208 
209       ArrayRef<DeclID> LazySpecializations;
210       if (auto *LS = Common->LazySpecializations)
211         LazySpecializations = llvm::makeArrayRef(LS + 1, LS[0]);
212 
213       // Add a slot to the record for the number of specializations.
214       unsigned I = Record.size();
215       Record.push_back(0);
216 
217       // AddFirstDeclFromEachModule might trigger deserialization, invalidating
218       // *Specializations iterators.
219       llvm::SmallVector<const Decl*, 16> Specs;
220       for (auto &Entry : Common->Specializations)
221         Specs.push_back(getSpecializationDecl(Entry));
222       for (auto &Entry : getPartialSpecializations(Common))
223         Specs.push_back(getSpecializationDecl(Entry));
224 
225       for (auto *D : Specs) {
226         assert(D->isCanonicalDecl() && "non-canonical decl in set");
227         AddFirstDeclFromEachModule(D, /*IncludeLocal*/true);
228       }
229       Record.append(LazySpecializations.begin(), LazySpecializations.end());
230 
231       // Update the size entry we added earlier.
232       Record[I] = Record.size() - I - 1;
233     }
234 
235     /// Ensure that this template specialization is associated with the specified
236     /// template on reload.
237     void RegisterTemplateSpecialization(const Decl *Template,
238                                         const Decl *Specialization) {
239       Template = Template->getCanonicalDecl();
240 
241       // If the canonical template is local, we'll write out this specialization
242       // when we emit it.
243       // FIXME: We can do the same thing if there is any local declaration of
244       // the template, to avoid emitting an update record.
245       if (!Template->isFromASTFile())
246         return;
247 
248       // We only need to associate the first local declaration of the
249       // specialization. The other declarations will get pulled in by it.
250       if (Writer.getFirstLocalDecl(Specialization) != Specialization)
251         return;
252 
253       Writer.DeclUpdates[Template].push_back(ASTWriter::DeclUpdate(
254           UPD_CXX_ADDED_TEMPLATE_SPECIALIZATION, Specialization));
255     }
256   };
257 }
258 
259 void ASTDeclWriter::Visit(Decl *D) {
260   DeclVisitor<ASTDeclWriter>::Visit(D);
261 
262   // Source locations require array (variable-length) abbreviations.  The
263   // abbreviation infrastructure requires that arrays are encoded last, so
264   // we handle it here in the case of those classes derived from DeclaratorDecl
265   if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)) {
266     Record.AddTypeSourceInfo(DD->getTypeSourceInfo());
267   }
268 
269   // Handle FunctionDecl's body here and write it after all other Stmts/Exprs
270   // have been written. We want it last because we will not read it back when
271   // retrieving it from the AST, we'll just lazily set the offset.
272   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
273     Record.push_back(FD->doesThisDeclarationHaveABody());
274     if (FD->doesThisDeclarationHaveABody())
275       Record.AddFunctionDefinition(FD);
276   }
277 
278   // If this declaration is also a DeclContext, write blocks for the
279   // declarations that lexically stored inside its context and those
280   // declarations that are visible from its context.
281   if (DeclContext *DC = dyn_cast<DeclContext>(D))
282     VisitDeclContext(DC);
283 }
284 
285 void ASTDeclWriter::VisitDecl(Decl *D) {
286   Record.AddDeclRef(cast_or_null<Decl>(D->getDeclContext()));
287   if (D->getDeclContext() != D->getLexicalDeclContext())
288     Record.AddDeclRef(cast_or_null<Decl>(D->getLexicalDeclContext()));
289   else
290     Record.push_back(0);
291   Record.push_back(D->isInvalidDecl());
292   Record.push_back(D->hasAttrs());
293   if (D->hasAttrs())
294     Record.AddAttributes(D->getAttrs());
295   Record.push_back(D->isImplicit());
296   Record.push_back(D->isUsed(false));
297   Record.push_back(D->isReferenced());
298   Record.push_back(D->isTopLevelDeclInObjCContainer());
299   Record.push_back(D->getAccess());
300   Record.push_back(D->isModulePrivate());
301   Record.push_back(Writer.inferSubmoduleIDFromLocation(D->getLocation()));
302 
303   // If this declaration injected a name into a context different from its
304   // lexical context, and that context is an imported namespace, we need to
305   // update its visible declarations to include this name.
306   //
307   // This happens when we instantiate a class with a friend declaration or a
308   // function with a local extern declaration, for instance.
309   //
310   // FIXME: Can we handle this in AddedVisibleDecl instead?
311   if (D->isOutOfLine()) {
312     auto *DC = D->getDeclContext();
313     while (auto *NS = dyn_cast<NamespaceDecl>(DC->getRedeclContext())) {
314       if (!NS->isFromASTFile())
315         break;
316       Writer.UpdatedDeclContexts.insert(NS->getPrimaryContext());
317       if (!NS->isInlineNamespace())
318         break;
319       DC = NS->getParent();
320     }
321   }
322 }
323 
324 void ASTDeclWriter::VisitPragmaCommentDecl(PragmaCommentDecl *D) {
325   StringRef Arg = D->getArg();
326   Record.push_back(Arg.size());
327   VisitDecl(D);
328   Record.AddSourceLocation(D->getLocStart());
329   Record.push_back(D->getCommentKind());
330   Record.AddString(Arg);
331   Code = serialization::DECL_PRAGMA_COMMENT;
332 }
333 
334 void ASTDeclWriter::VisitPragmaDetectMismatchDecl(
335     PragmaDetectMismatchDecl *D) {
336   StringRef Name = D->getName();
337   StringRef Value = D->getValue();
338   Record.push_back(Name.size() + 1 + Value.size());
339   VisitDecl(D);
340   Record.AddSourceLocation(D->getLocStart());
341   Record.AddString(Name);
342   Record.AddString(Value);
343   Code = serialization::DECL_PRAGMA_DETECT_MISMATCH;
344 }
345 
346 void ASTDeclWriter::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
347   llvm_unreachable("Translation units aren't directly serialized");
348 }
349 
350 void ASTDeclWriter::VisitNamedDecl(NamedDecl *D) {
351   VisitDecl(D);
352   Record.AddDeclarationName(D->getDeclName());
353   Record.push_back(needsAnonymousDeclarationNumber(D)
354                        ? Writer.getAnonymousDeclarationNumber(D)
355                        : 0);
356 }
357 
358 void ASTDeclWriter::VisitTypeDecl(TypeDecl *D) {
359   VisitNamedDecl(D);
360   Record.AddSourceLocation(D->getLocStart());
361   Record.AddTypeRef(QualType(D->getTypeForDecl(), 0));
362 }
363 
364 void ASTDeclWriter::VisitTypedefNameDecl(TypedefNameDecl *D) {
365   VisitRedeclarable(D);
366   VisitTypeDecl(D);
367   Record.AddTypeSourceInfo(D->getTypeSourceInfo());
368   Record.push_back(D->isModed());
369   if (D->isModed())
370     Record.AddTypeRef(D->getUnderlyingType());
371   Record.AddDeclRef(D->getAnonDeclWithTypedefName(false));
372 }
373 
374 void ASTDeclWriter::VisitTypedefDecl(TypedefDecl *D) {
375   VisitTypedefNameDecl(D);
376   if (D->getDeclContext() == D->getLexicalDeclContext() &&
377       !D->hasAttrs() &&
378       !D->isImplicit() &&
379       D->getFirstDecl() == D->getMostRecentDecl() &&
380       !D->isInvalidDecl() &&
381       !D->isTopLevelDeclInObjCContainer() &&
382       !D->isModulePrivate() &&
383       !needsAnonymousDeclarationNumber(D) &&
384       D->getDeclName().getNameKind() == DeclarationName::Identifier)
385     AbbrevToUse = Writer.getDeclTypedefAbbrev();
386 
387   Code = serialization::DECL_TYPEDEF;
388 }
389 
390 void ASTDeclWriter::VisitTypeAliasDecl(TypeAliasDecl *D) {
391   VisitTypedefNameDecl(D);
392   Record.AddDeclRef(D->getDescribedAliasTemplate());
393   Code = serialization::DECL_TYPEALIAS;
394 }
395 
396 void ASTDeclWriter::VisitTagDecl(TagDecl *D) {
397   VisitRedeclarable(D);
398   VisitTypeDecl(D);
399   Record.push_back(D->getIdentifierNamespace());
400   Record.push_back((unsigned)D->getTagKind()); // FIXME: stable encoding
401   if (!isa<CXXRecordDecl>(D))
402     Record.push_back(D->isCompleteDefinition());
403   Record.push_back(D->isEmbeddedInDeclarator());
404   Record.push_back(D->isFreeStanding());
405   Record.push_back(D->isCompleteDefinitionRequired());
406   Record.AddSourceRange(D->getBraceRange());
407 
408   if (D->hasExtInfo()) {
409     Record.push_back(1);
410     Record.AddQualifierInfo(*D->getExtInfo());
411   } else if (auto *TD = D->getTypedefNameForAnonDecl()) {
412     Record.push_back(2);
413     Record.AddDeclRef(TD);
414     Record.AddIdentifierRef(TD->getDeclName().getAsIdentifierInfo());
415   } else {
416     Record.push_back(0);
417   }
418 }
419 
420 void ASTDeclWriter::VisitEnumDecl(EnumDecl *D) {
421   VisitTagDecl(D);
422   Record.AddTypeSourceInfo(D->getIntegerTypeSourceInfo());
423   if (!D->getIntegerTypeSourceInfo())
424     Record.AddTypeRef(D->getIntegerType());
425   Record.AddTypeRef(D->getPromotionType());
426   Record.push_back(D->getNumPositiveBits());
427   Record.push_back(D->getNumNegativeBits());
428   Record.push_back(D->isScoped());
429   Record.push_back(D->isScopedUsingClassTag());
430   Record.push_back(D->isFixed());
431   if (MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo()) {
432     Record.AddDeclRef(MemberInfo->getInstantiatedFrom());
433     Record.push_back(MemberInfo->getTemplateSpecializationKind());
434     Record.AddSourceLocation(MemberInfo->getPointOfInstantiation());
435   } else {
436     Record.AddDeclRef(nullptr);
437   }
438 
439   if (D->getDeclContext() == D->getLexicalDeclContext() &&
440       !D->hasAttrs() &&
441       !D->isImplicit() &&
442       !D->isUsed(false) &&
443       !D->hasExtInfo() &&
444       !D->getTypedefNameForAnonDecl() &&
445       D->getFirstDecl() == D->getMostRecentDecl() &&
446       !D->isInvalidDecl() &&
447       !D->isReferenced() &&
448       !D->isTopLevelDeclInObjCContainer() &&
449       D->getAccess() == AS_none &&
450       !D->isModulePrivate() &&
451       !CXXRecordDecl::classofKind(D->getKind()) &&
452       !D->getIntegerTypeSourceInfo() &&
453       !D->getMemberSpecializationInfo() &&
454       !needsAnonymousDeclarationNumber(D) &&
455       D->getDeclName().getNameKind() == DeclarationName::Identifier)
456     AbbrevToUse = Writer.getDeclEnumAbbrev();
457 
458   Code = serialization::DECL_ENUM;
459 }
460 
461 void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
462   VisitTagDecl(D);
463   Record.push_back(D->hasFlexibleArrayMember());
464   Record.push_back(D->isAnonymousStructOrUnion());
465   Record.push_back(D->hasObjectMember());
466   Record.push_back(D->hasVolatileMember());
467 
468   if (D->getDeclContext() == D->getLexicalDeclContext() &&
469       !D->hasAttrs() &&
470       !D->isImplicit() &&
471       !D->isUsed(false) &&
472       !D->hasExtInfo() &&
473       !D->getTypedefNameForAnonDecl() &&
474       D->getFirstDecl() == D->getMostRecentDecl() &&
475       !D->isInvalidDecl() &&
476       !D->isReferenced() &&
477       !D->isTopLevelDeclInObjCContainer() &&
478       D->getAccess() == AS_none &&
479       !D->isModulePrivate() &&
480       !CXXRecordDecl::classofKind(D->getKind()) &&
481       !needsAnonymousDeclarationNumber(D) &&
482       D->getDeclName().getNameKind() == DeclarationName::Identifier)
483     AbbrevToUse = Writer.getDeclRecordAbbrev();
484 
485   Code = serialization::DECL_RECORD;
486 }
487 
488 void ASTDeclWriter::VisitValueDecl(ValueDecl *D) {
489   VisitNamedDecl(D);
490   Record.AddTypeRef(D->getType());
491 }
492 
493 void ASTDeclWriter::VisitEnumConstantDecl(EnumConstantDecl *D) {
494   VisitValueDecl(D);
495   Record.push_back(D->getInitExpr()? 1 : 0);
496   if (D->getInitExpr())
497     Record.AddStmt(D->getInitExpr());
498   Record.AddAPSInt(D->getInitVal());
499 
500   Code = serialization::DECL_ENUM_CONSTANT;
501 }
502 
503 void ASTDeclWriter::VisitDeclaratorDecl(DeclaratorDecl *D) {
504   VisitValueDecl(D);
505   Record.AddSourceLocation(D->getInnerLocStart());
506   Record.push_back(D->hasExtInfo());
507   if (D->hasExtInfo())
508     Record.AddQualifierInfo(*D->getExtInfo());
509 }
510 
511 void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
512   VisitRedeclarable(D);
513   VisitDeclaratorDecl(D);
514   Record.AddDeclarationNameLoc(D->DNLoc, D->getDeclName());
515   Record.push_back(D->getIdentifierNamespace());
516 
517   // FunctionDecl's body is handled last at ASTWriterDecl::Visit,
518   // after everything else is written.
519 
520   Record.push_back((int)D->SClass); // FIXME: stable encoding
521   Record.push_back(D->IsInline);
522   Record.push_back(D->IsInlineSpecified);
523   Record.push_back(D->IsVirtualAsWritten);
524   Record.push_back(D->IsPure);
525   Record.push_back(D->HasInheritedPrototype);
526   Record.push_back(D->HasWrittenPrototype);
527   Record.push_back(D->IsDeleted);
528   Record.push_back(D->IsTrivial);
529   Record.push_back(D->IsDefaulted);
530   Record.push_back(D->IsExplicitlyDefaulted);
531   Record.push_back(D->HasImplicitReturnZero);
532   Record.push_back(D->IsConstexpr);
533   Record.push_back(D->UsesSEHTry);
534   Record.push_back(D->HasSkippedBody);
535   Record.push_back(D->IsLateTemplateParsed);
536   Record.push_back(D->getLinkageInternal());
537   Record.AddSourceLocation(D->getLocEnd());
538 
539   Record.push_back(D->getTemplatedKind());
540   switch (D->getTemplatedKind()) {
541   case FunctionDecl::TK_NonTemplate:
542     break;
543   case FunctionDecl::TK_FunctionTemplate:
544     Record.AddDeclRef(D->getDescribedFunctionTemplate());
545     break;
546   case FunctionDecl::TK_MemberSpecialization: {
547     MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo();
548     Record.AddDeclRef(MemberInfo->getInstantiatedFrom());
549     Record.push_back(MemberInfo->getTemplateSpecializationKind());
550     Record.AddSourceLocation(MemberInfo->getPointOfInstantiation());
551     break;
552   }
553   case FunctionDecl::TK_FunctionTemplateSpecialization: {
554     FunctionTemplateSpecializationInfo *
555       FTSInfo = D->getTemplateSpecializationInfo();
556 
557     RegisterTemplateSpecialization(FTSInfo->getTemplate(), D);
558 
559     Record.AddDeclRef(FTSInfo->getTemplate());
560     Record.push_back(FTSInfo->getTemplateSpecializationKind());
561 
562     // Template arguments.
563     Record.AddTemplateArgumentList(FTSInfo->TemplateArguments);
564 
565     // Template args as written.
566     Record.push_back(FTSInfo->TemplateArgumentsAsWritten != nullptr);
567     if (FTSInfo->TemplateArgumentsAsWritten) {
568       Record.push_back(FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs);
569       for (int i=0, e = FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs;
570              i!=e; ++i)
571         Record.AddTemplateArgumentLoc(
572             (*FTSInfo->TemplateArgumentsAsWritten)[i]);
573       Record.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->LAngleLoc);
574       Record.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->RAngleLoc);
575     }
576 
577     Record.AddSourceLocation(FTSInfo->getPointOfInstantiation());
578 
579     if (D->isCanonicalDecl()) {
580       // Write the template that contains the specializations set. We will
581       // add a FunctionTemplateSpecializationInfo to it when reading.
582       Record.AddDeclRef(FTSInfo->getTemplate()->getCanonicalDecl());
583     }
584     break;
585   }
586   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
587     DependentFunctionTemplateSpecializationInfo *
588       DFTSInfo = D->getDependentSpecializationInfo();
589 
590     // Templates.
591     Record.push_back(DFTSInfo->getNumTemplates());
592     for (int i=0, e = DFTSInfo->getNumTemplates(); i != e; ++i)
593       Record.AddDeclRef(DFTSInfo->getTemplate(i));
594 
595     // Templates args.
596     Record.push_back(DFTSInfo->getNumTemplateArgs());
597     for (int i=0, e = DFTSInfo->getNumTemplateArgs(); i != e; ++i)
598       Record.AddTemplateArgumentLoc(DFTSInfo->getTemplateArg(i));
599     Record.AddSourceLocation(DFTSInfo->getLAngleLoc());
600     Record.AddSourceLocation(DFTSInfo->getRAngleLoc());
601     break;
602   }
603   }
604 
605   Record.push_back(D->param_size());
606   for (auto P : D->parameters())
607     Record.AddDeclRef(P);
608   Code = serialization::DECL_FUNCTION;
609 }
610 
611 void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
612   VisitNamedDecl(D);
613   // FIXME: convert to LazyStmtPtr?
614   // Unlike C/C++, method bodies will never be in header files.
615   bool HasBodyStuff = D->getBody() != nullptr     ||
616                       D->getSelfDecl() != nullptr || D->getCmdDecl() != nullptr;
617   Record.push_back(HasBodyStuff);
618   if (HasBodyStuff) {
619     Record.AddStmt(D->getBody());
620     Record.AddDeclRef(D->getSelfDecl());
621     Record.AddDeclRef(D->getCmdDecl());
622   }
623   Record.push_back(D->isInstanceMethod());
624   Record.push_back(D->isVariadic());
625   Record.push_back(D->isPropertyAccessor());
626   Record.push_back(D->isDefined());
627   Record.push_back(D->IsOverriding);
628   Record.push_back(D->HasSkippedBody);
629 
630   Record.push_back(D->IsRedeclaration);
631   Record.push_back(D->HasRedeclaration);
632   if (D->HasRedeclaration) {
633     assert(Context.getObjCMethodRedeclaration(D));
634     Record.AddDeclRef(Context.getObjCMethodRedeclaration(D));
635   }
636 
637   // FIXME: stable encoding for @required/@optional
638   Record.push_back(D->getImplementationControl());
639   // FIXME: stable encoding for in/out/inout/bycopy/byref/oneway/nullability
640   Record.push_back(D->getObjCDeclQualifier());
641   Record.push_back(D->hasRelatedResultType());
642   Record.AddTypeRef(D->getReturnType());
643   Record.AddTypeSourceInfo(D->getReturnTypeSourceInfo());
644   Record.AddSourceLocation(D->getLocEnd());
645   Record.push_back(D->param_size());
646   for (const auto *P : D->parameters())
647     Record.AddDeclRef(P);
648 
649   Record.push_back(D->SelLocsKind);
650   unsigned NumStoredSelLocs = D->getNumStoredSelLocs();
651   SourceLocation *SelLocs = D->getStoredSelLocs();
652   Record.push_back(NumStoredSelLocs);
653   for (unsigned i = 0; i != NumStoredSelLocs; ++i)
654     Record.AddSourceLocation(SelLocs[i]);
655 
656   Code = serialization::DECL_OBJC_METHOD;
657 }
658 
659 void ASTDeclWriter::VisitObjCTypeParamDecl(ObjCTypeParamDecl *D) {
660   VisitTypedefNameDecl(D);
661   Record.push_back(D->Variance);
662   Record.push_back(D->Index);
663   Record.AddSourceLocation(D->VarianceLoc);
664   Record.AddSourceLocation(D->ColonLoc);
665 
666   Code = serialization::DECL_OBJC_TYPE_PARAM;
667 }
668 
669 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
670   VisitNamedDecl(D);
671   Record.AddSourceLocation(D->getAtStartLoc());
672   Record.AddSourceRange(D->getAtEndRange());
673   // Abstract class (no need to define a stable serialization::DECL code).
674 }
675 
676 void ASTDeclWriter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
677   VisitRedeclarable(D);
678   VisitObjCContainerDecl(D);
679   Record.AddTypeRef(QualType(D->getTypeForDecl(), 0));
680   AddObjCTypeParamList(D->TypeParamList);
681 
682   Record.push_back(D->isThisDeclarationADefinition());
683   if (D->isThisDeclarationADefinition()) {
684     // Write the DefinitionData
685     ObjCInterfaceDecl::DefinitionData &Data = D->data();
686 
687     Record.AddTypeSourceInfo(D->getSuperClassTInfo());
688     Record.AddSourceLocation(D->getEndOfDefinitionLoc());
689     Record.push_back(Data.HasDesignatedInitializers);
690 
691     // Write out the protocols that are directly referenced by the @interface.
692     Record.push_back(Data.ReferencedProtocols.size());
693     for (const auto *P : D->protocols())
694       Record.AddDeclRef(P);
695     for (const auto &PL : D->protocol_locs())
696       Record.AddSourceLocation(PL);
697 
698     // Write out the protocols that are transitively referenced.
699     Record.push_back(Data.AllReferencedProtocols.size());
700     for (ObjCList<ObjCProtocolDecl>::iterator
701               P = Data.AllReferencedProtocols.begin(),
702            PEnd = Data.AllReferencedProtocols.end();
703          P != PEnd; ++P)
704       Record.AddDeclRef(*P);
705 
706 
707     if (ObjCCategoryDecl *Cat = D->getCategoryListRaw()) {
708       // Ensure that we write out the set of categories for this class.
709       Writer.ObjCClassesWithCategories.insert(D);
710 
711       // Make sure that the categories get serialized.
712       for (; Cat; Cat = Cat->getNextClassCategoryRaw())
713         (void)Writer.GetDeclRef(Cat);
714     }
715   }
716 
717   Code = serialization::DECL_OBJC_INTERFACE;
718 }
719 
720 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
721   VisitFieldDecl(D);
722   // FIXME: stable encoding for @public/@private/@protected/@package
723   Record.push_back(D->getAccessControl());
724   Record.push_back(D->getSynthesize());
725 
726   if (D->getDeclContext() == D->getLexicalDeclContext() &&
727       !D->hasAttrs() &&
728       !D->isImplicit() &&
729       !D->isUsed(false) &&
730       !D->isInvalidDecl() &&
731       !D->isReferenced() &&
732       !D->isModulePrivate() &&
733       !D->getBitWidth() &&
734       !D->hasExtInfo() &&
735       D->getDeclName())
736     AbbrevToUse = Writer.getDeclObjCIvarAbbrev();
737 
738   Code = serialization::DECL_OBJC_IVAR;
739 }
740 
741 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
742   VisitRedeclarable(D);
743   VisitObjCContainerDecl(D);
744 
745   Record.push_back(D->isThisDeclarationADefinition());
746   if (D->isThisDeclarationADefinition()) {
747     Record.push_back(D->protocol_size());
748     for (const auto *I : D->protocols())
749       Record.AddDeclRef(I);
750     for (const auto &PL : D->protocol_locs())
751       Record.AddSourceLocation(PL);
752   }
753 
754   Code = serialization::DECL_OBJC_PROTOCOL;
755 }
756 
757 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
758   VisitFieldDecl(D);
759   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
760 }
761 
762 void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
763   VisitObjCContainerDecl(D);
764   Record.AddSourceLocation(D->getCategoryNameLoc());
765   Record.AddSourceLocation(D->getIvarLBraceLoc());
766   Record.AddSourceLocation(D->getIvarRBraceLoc());
767   Record.AddDeclRef(D->getClassInterface());
768   AddObjCTypeParamList(D->TypeParamList);
769   Record.push_back(D->protocol_size());
770   for (const auto *I : D->protocols())
771     Record.AddDeclRef(I);
772   for (const auto &PL : D->protocol_locs())
773     Record.AddSourceLocation(PL);
774   Code = serialization::DECL_OBJC_CATEGORY;
775 }
776 
777 void ASTDeclWriter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D) {
778   VisitNamedDecl(D);
779   Record.AddDeclRef(D->getClassInterface());
780   Code = serialization::DECL_OBJC_COMPATIBLE_ALIAS;
781 }
782 
783 void ASTDeclWriter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
784   VisitNamedDecl(D);
785   Record.AddSourceLocation(D->getAtLoc());
786   Record.AddSourceLocation(D->getLParenLoc());
787   Record.AddTypeRef(D->getType());
788   Record.AddTypeSourceInfo(D->getTypeSourceInfo());
789   // FIXME: stable encoding
790   Record.push_back((unsigned)D->getPropertyAttributes());
791   Record.push_back((unsigned)D->getPropertyAttributesAsWritten());
792   // FIXME: stable encoding
793   Record.push_back((unsigned)D->getPropertyImplementation());
794   Record.AddDeclarationName(D->getGetterName());
795   Record.AddDeclarationName(D->getSetterName());
796   Record.AddDeclRef(D->getGetterMethodDecl());
797   Record.AddDeclRef(D->getSetterMethodDecl());
798   Record.AddDeclRef(D->getPropertyIvarDecl());
799   Code = serialization::DECL_OBJC_PROPERTY;
800 }
801 
802 void ASTDeclWriter::VisitObjCImplDecl(ObjCImplDecl *D) {
803   VisitObjCContainerDecl(D);
804   Record.AddDeclRef(D->getClassInterface());
805   // Abstract class (no need to define a stable serialization::DECL code).
806 }
807 
808 void ASTDeclWriter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
809   VisitObjCImplDecl(D);
810   Record.AddIdentifierRef(D->getIdentifier());
811   Record.AddSourceLocation(D->getCategoryNameLoc());
812   Code = serialization::DECL_OBJC_CATEGORY_IMPL;
813 }
814 
815 void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
816   VisitObjCImplDecl(D);
817   Record.AddDeclRef(D->getSuperClass());
818   Record.AddSourceLocation(D->getSuperClassLoc());
819   Record.AddSourceLocation(D->getIvarLBraceLoc());
820   Record.AddSourceLocation(D->getIvarRBraceLoc());
821   Record.push_back(D->hasNonZeroConstructors());
822   Record.push_back(D->hasDestructors());
823   Record.push_back(D->NumIvarInitializers);
824   if (D->NumIvarInitializers)
825     Record.AddCXXCtorInitializers(
826         llvm::makeArrayRef(D->init_begin(), D->init_end()));
827   Code = serialization::DECL_OBJC_IMPLEMENTATION;
828 }
829 
830 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
831   VisitDecl(D);
832   Record.AddSourceLocation(D->getLocStart());
833   Record.AddDeclRef(D->getPropertyDecl());
834   Record.AddDeclRef(D->getPropertyIvarDecl());
835   Record.AddSourceLocation(D->getPropertyIvarDeclLoc());
836   Record.AddStmt(D->getGetterCXXConstructor());
837   Record.AddStmt(D->getSetterCXXAssignment());
838   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
839 }
840 
841 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
842   VisitDeclaratorDecl(D);
843   Record.push_back(D->isMutable());
844   if (D->InitStorage.getInt() == FieldDecl::ISK_BitWidthOrNothing &&
845       D->InitStorage.getPointer() == nullptr) {
846     Record.push_back(0);
847   } else if (D->InitStorage.getInt() == FieldDecl::ISK_CapturedVLAType) {
848     Record.push_back(D->InitStorage.getInt() + 1);
849     Record.AddTypeRef(
850         QualType(static_cast<Type *>(D->InitStorage.getPointer()), 0));
851   } else {
852     Record.push_back(D->InitStorage.getInt() + 1);
853     Record.AddStmt(static_cast<Expr *>(D->InitStorage.getPointer()));
854   }
855   if (!D->getDeclName())
856     Record.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D));
857 
858   if (D->getDeclContext() == D->getLexicalDeclContext() &&
859       !D->hasAttrs() &&
860       !D->isImplicit() &&
861       !D->isUsed(false) &&
862       !D->isInvalidDecl() &&
863       !D->isReferenced() &&
864       !D->isTopLevelDeclInObjCContainer() &&
865       !D->isModulePrivate() &&
866       !D->getBitWidth() &&
867       !D->hasInClassInitializer() &&
868       !D->hasExtInfo() &&
869       !ObjCIvarDecl::classofKind(D->getKind()) &&
870       !ObjCAtDefsFieldDecl::classofKind(D->getKind()) &&
871       D->getDeclName())
872     AbbrevToUse = Writer.getDeclFieldAbbrev();
873 
874   Code = serialization::DECL_FIELD;
875 }
876 
877 void ASTDeclWriter::VisitMSPropertyDecl(MSPropertyDecl *D) {
878   VisitDeclaratorDecl(D);
879   Record.AddIdentifierRef(D->getGetterId());
880   Record.AddIdentifierRef(D->getSetterId());
881   Code = serialization::DECL_MS_PROPERTY;
882 }
883 
884 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
885   VisitValueDecl(D);
886   Record.push_back(D->getChainingSize());
887 
888   for (const auto *P : D->chain())
889     Record.AddDeclRef(P);
890   Code = serialization::DECL_INDIRECTFIELD;
891 }
892 
893 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
894   VisitRedeclarable(D);
895   VisitDeclaratorDecl(D);
896   Record.push_back(D->getStorageClass());
897   Record.push_back(D->getTSCSpec());
898   Record.push_back(D->getInitStyle());
899   if (!isa<ParmVarDecl>(D)) {
900     Record.push_back(D->isThisDeclarationADemotedDefinition());
901     Record.push_back(D->isExceptionVariable());
902     Record.push_back(D->isNRVOVariable());
903     Record.push_back(D->isCXXForRangeDecl());
904     Record.push_back(D->isARCPseudoStrong());
905     Record.push_back(D->isInline());
906     Record.push_back(D->isInlineSpecified());
907     Record.push_back(D->isConstexpr());
908     Record.push_back(D->isInitCapture());
909     Record.push_back(D->isPreviousDeclInSameBlockScope());
910   }
911   Record.push_back(D->getLinkageInternal());
912 
913   if (D->getInit()) {
914     Record.push_back(!D->isInitKnownICE() ? 1 : (D->isInitICE() ? 3 : 2));
915     Record.AddStmt(D->getInit());
916   } else {
917     Record.push_back(0);
918   }
919 
920   enum {
921     VarNotTemplate = 0, VarTemplate, StaticDataMemberSpecialization
922   };
923   if (VarTemplateDecl *TemplD = D->getDescribedVarTemplate()) {
924     Record.push_back(VarTemplate);
925     Record.AddDeclRef(TemplD);
926   } else if (MemberSpecializationInfo *SpecInfo
927                = D->getMemberSpecializationInfo()) {
928     Record.push_back(StaticDataMemberSpecialization);
929     Record.AddDeclRef(SpecInfo->getInstantiatedFrom());
930     Record.push_back(SpecInfo->getTemplateSpecializationKind());
931     Record.AddSourceLocation(SpecInfo->getPointOfInstantiation());
932   } else {
933     Record.push_back(VarNotTemplate);
934   }
935 
936   if (D->getDeclContext() == D->getLexicalDeclContext() &&
937       !D->hasAttrs() &&
938       !D->isImplicit() &&
939       !D->isUsed(false) &&
940       !D->isInvalidDecl() &&
941       !D->isReferenced() &&
942       !D->isTopLevelDeclInObjCContainer() &&
943       D->getAccess() == AS_none &&
944       !D->isModulePrivate() &&
945       !needsAnonymousDeclarationNumber(D) &&
946       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
947       !D->hasExtInfo() &&
948       D->getFirstDecl() == D->getMostRecentDecl() &&
949       D->getKind() == Decl::Var &&
950       !D->isInline() &&
951       !D->isConstexpr() &&
952       !D->isInitCapture() &&
953       !D->isPreviousDeclInSameBlockScope() &&
954       !D->getMemberSpecializationInfo())
955     AbbrevToUse = Writer.getDeclVarAbbrev();
956 
957   Code = serialization::DECL_VAR;
958 }
959 
960 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
961   VisitVarDecl(D);
962   Code = serialization::DECL_IMPLICIT_PARAM;
963 }
964 
965 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
966   VisitVarDecl(D);
967   Record.push_back(D->isObjCMethodParameter());
968   Record.push_back(D->getFunctionScopeDepth());
969   Record.push_back(D->getFunctionScopeIndex());
970   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
971   Record.push_back(D->isKNRPromoted());
972   Record.push_back(D->hasInheritedDefaultArg());
973   Record.push_back(D->hasUninstantiatedDefaultArg());
974   if (D->hasUninstantiatedDefaultArg())
975     Record.AddStmt(D->getUninstantiatedDefaultArg());
976   Code = serialization::DECL_PARM_VAR;
977 
978   assert(!D->isARCPseudoStrong()); // can be true of ImplicitParamDecl
979 
980   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
981   // we dynamically check for the properties that we optimize for, but don't
982   // know are true of all PARM_VAR_DECLs.
983   if (D->getDeclContext() == D->getLexicalDeclContext() &&
984       !D->hasAttrs() &&
985       !D->hasExtInfo() &&
986       !D->isImplicit() &&
987       !D->isUsed(false) &&
988       !D->isInvalidDecl() &&
989       !D->isReferenced() &&
990       D->getAccess() == AS_none &&
991       !D->isModulePrivate() &&
992       D->getStorageClass() == 0 &&
993       D->getInitStyle() == VarDecl::CInit && // Can params have anything else?
994       D->getFunctionScopeDepth() == 0 &&
995       D->getObjCDeclQualifier() == 0 &&
996       !D->isKNRPromoted() &&
997       !D->hasInheritedDefaultArg() &&
998       D->getInit() == nullptr &&
999       !D->hasUninstantiatedDefaultArg())  // No default expr.
1000     AbbrevToUse = Writer.getDeclParmVarAbbrev();
1001 
1002   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
1003   // just us assuming it.
1004   assert(!D->getTSCSpec() && "PARM_VAR_DECL can't use TLS");
1005   assert(!D->isThisDeclarationADemotedDefinition()
1006          && "PARM_VAR_DECL can't be demoted definition.");
1007   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
1008   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
1009   assert(D->getPreviousDecl() == nullptr && "PARM_VAR_DECL can't be redecl");
1010   assert(!D->isStaticDataMember() &&
1011          "PARM_VAR_DECL can't be static data member");
1012 }
1013 
1014 void ASTDeclWriter::VisitDecompositionDecl(DecompositionDecl *D) {
1015   // Record the number of bindings first to simplify deserialization.
1016   Record.push_back(D->bindings().size());
1017 
1018   VisitVarDecl(D);
1019   for (auto *B : D->bindings())
1020     Record.AddDeclRef(B);
1021   Code = serialization::DECL_DECOMPOSITION;
1022 }
1023 
1024 void ASTDeclWriter::VisitBindingDecl(BindingDecl *D) {
1025   VisitValueDecl(D);
1026   Record.AddStmt(D->getBinding());
1027   Code = serialization::DECL_BINDING;
1028 }
1029 
1030 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
1031   VisitDecl(D);
1032   Record.AddStmt(D->getAsmString());
1033   Record.AddSourceLocation(D->getRParenLoc());
1034   Code = serialization::DECL_FILE_SCOPE_ASM;
1035 }
1036 
1037 void ASTDeclWriter::VisitEmptyDecl(EmptyDecl *D) {
1038   VisitDecl(D);
1039   Code = serialization::DECL_EMPTY;
1040 }
1041 
1042 void ASTDeclWriter::VisitBlockDecl(BlockDecl *D) {
1043   VisitDecl(D);
1044   Record.AddStmt(D->getBody());
1045   Record.AddTypeSourceInfo(D->getSignatureAsWritten());
1046   Record.push_back(D->param_size());
1047   for (ParmVarDecl *P : D->parameters())
1048     Record.AddDeclRef(P);
1049   Record.push_back(D->isVariadic());
1050   Record.push_back(D->blockMissingReturnType());
1051   Record.push_back(D->isConversionFromLambda());
1052   Record.push_back(D->capturesCXXThis());
1053   Record.push_back(D->getNumCaptures());
1054   for (const auto &capture : D->captures()) {
1055     Record.AddDeclRef(capture.getVariable());
1056 
1057     unsigned flags = 0;
1058     if (capture.isByRef()) flags |= 1;
1059     if (capture.isNested()) flags |= 2;
1060     if (capture.hasCopyExpr()) flags |= 4;
1061     Record.push_back(flags);
1062 
1063     if (capture.hasCopyExpr()) Record.AddStmt(capture.getCopyExpr());
1064   }
1065 
1066   Code = serialization::DECL_BLOCK;
1067 }
1068 
1069 void ASTDeclWriter::VisitCapturedDecl(CapturedDecl *CD) {
1070   Record.push_back(CD->getNumParams());
1071   VisitDecl(CD);
1072   Record.push_back(CD->getContextParamPosition());
1073   Record.push_back(CD->isNothrow() ? 1 : 0);
1074   // Body is stored by VisitCapturedStmt.
1075   for (unsigned I = 0; I < CD->getNumParams(); ++I)
1076     Record.AddDeclRef(CD->getParam(I));
1077   Code = serialization::DECL_CAPTURED;
1078 }
1079 
1080 void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
1081   VisitDecl(D);
1082   Record.push_back(D->getLanguage());
1083   Record.AddSourceLocation(D->getExternLoc());
1084   Record.AddSourceLocation(D->getRBraceLoc());
1085   Code = serialization::DECL_LINKAGE_SPEC;
1086 }
1087 
1088 void ASTDeclWriter::VisitExportDecl(ExportDecl *D) {
1089   VisitDecl(D);
1090   Record.AddSourceLocation(D->getRBraceLoc());
1091   Code = serialization::DECL_EXPORT;
1092 }
1093 
1094 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
1095   VisitNamedDecl(D);
1096   Record.AddSourceLocation(D->getLocStart());
1097   Code = serialization::DECL_LABEL;
1098 }
1099 
1100 
1101 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
1102   VisitRedeclarable(D);
1103   VisitNamedDecl(D);
1104   Record.push_back(D->isInline());
1105   Record.AddSourceLocation(D->getLocStart());
1106   Record.AddSourceLocation(D->getRBraceLoc());
1107 
1108   if (D->isOriginalNamespace())
1109     Record.AddDeclRef(D->getAnonymousNamespace());
1110   Code = serialization::DECL_NAMESPACE;
1111 
1112   if (Writer.hasChain() && D->isAnonymousNamespace() &&
1113       D == D->getMostRecentDecl()) {
1114     // This is a most recent reopening of the anonymous namespace. If its parent
1115     // is in a previous PCH (or is the TU), mark that parent for update, because
1116     // the original namespace always points to the latest re-opening of its
1117     // anonymous namespace.
1118     Decl *Parent = cast<Decl>(
1119         D->getParent()->getRedeclContext()->getPrimaryContext());
1120     if (Parent->isFromASTFile() || isa<TranslationUnitDecl>(Parent)) {
1121       Writer.DeclUpdates[Parent].push_back(
1122           ASTWriter::DeclUpdate(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE, D));
1123     }
1124   }
1125 }
1126 
1127 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
1128   VisitRedeclarable(D);
1129   VisitNamedDecl(D);
1130   Record.AddSourceLocation(D->getNamespaceLoc());
1131   Record.AddSourceLocation(D->getTargetNameLoc());
1132   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1133   Record.AddDeclRef(D->getNamespace());
1134   Code = serialization::DECL_NAMESPACE_ALIAS;
1135 }
1136 
1137 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
1138   VisitNamedDecl(D);
1139   Record.AddSourceLocation(D->getUsingLoc());
1140   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1141   Record.AddDeclarationNameLoc(D->DNLoc, D->getDeclName());
1142   Record.AddDeclRef(D->FirstUsingShadow.getPointer());
1143   Record.push_back(D->hasTypename());
1144   Record.AddDeclRef(Context.getInstantiatedFromUsingDecl(D));
1145   Code = serialization::DECL_USING;
1146 }
1147 
1148 void ASTDeclWriter::VisitUsingPackDecl(UsingPackDecl *D) {
1149   Record.push_back(D->NumExpansions);
1150   VisitNamedDecl(D);
1151   Record.AddDeclRef(D->getInstantiatedFromUsingDecl());
1152   for (auto *E : D->expansions())
1153     Record.AddDeclRef(E);
1154   Code = serialization::DECL_USING_PACK;
1155 }
1156 
1157 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
1158   VisitRedeclarable(D);
1159   VisitNamedDecl(D);
1160   Record.AddDeclRef(D->getTargetDecl());
1161   Record.AddDeclRef(D->UsingOrNextShadow);
1162   Record.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D));
1163   Code = serialization::DECL_USING_SHADOW;
1164 }
1165 
1166 void ASTDeclWriter::VisitConstructorUsingShadowDecl(
1167     ConstructorUsingShadowDecl *D) {
1168   VisitUsingShadowDecl(D);
1169   Record.AddDeclRef(D->NominatedBaseClassShadowDecl);
1170   Record.AddDeclRef(D->ConstructedBaseClassShadowDecl);
1171   Record.push_back(D->IsVirtual);
1172   Code = serialization::DECL_CONSTRUCTOR_USING_SHADOW;
1173 }
1174 
1175 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
1176   VisitNamedDecl(D);
1177   Record.AddSourceLocation(D->getUsingLoc());
1178   Record.AddSourceLocation(D->getNamespaceKeyLocation());
1179   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1180   Record.AddDeclRef(D->getNominatedNamespace());
1181   Record.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()));
1182   Code = serialization::DECL_USING_DIRECTIVE;
1183 }
1184 
1185 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
1186   VisitValueDecl(D);
1187   Record.AddSourceLocation(D->getUsingLoc());
1188   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1189   Record.AddDeclarationNameLoc(D->DNLoc, D->getDeclName());
1190   Record.AddSourceLocation(D->getEllipsisLoc());
1191   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
1192 }
1193 
1194 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
1195                                                UnresolvedUsingTypenameDecl *D) {
1196   VisitTypeDecl(D);
1197   Record.AddSourceLocation(D->getTypenameLoc());
1198   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1199   Record.AddSourceLocation(D->getEllipsisLoc());
1200   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
1201 }
1202 
1203 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
1204   VisitRecordDecl(D);
1205 
1206   enum {
1207     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
1208   };
1209   if (ClassTemplateDecl *TemplD = D->getDescribedClassTemplate()) {
1210     Record.push_back(CXXRecTemplate);
1211     Record.AddDeclRef(TemplD);
1212   } else if (MemberSpecializationInfo *MSInfo
1213                = D->getMemberSpecializationInfo()) {
1214     Record.push_back(CXXRecMemberSpecialization);
1215     Record.AddDeclRef(MSInfo->getInstantiatedFrom());
1216     Record.push_back(MSInfo->getTemplateSpecializationKind());
1217     Record.AddSourceLocation(MSInfo->getPointOfInstantiation());
1218   } else {
1219     Record.push_back(CXXRecNotTemplate);
1220   }
1221 
1222   Record.push_back(D->isThisDeclarationADefinition());
1223   if (D->isThisDeclarationADefinition())
1224     Record.AddCXXDefinitionData(D);
1225 
1226   // Store (what we currently believe to be) the key function to avoid
1227   // deserializing every method so we can compute it.
1228   if (D->IsCompleteDefinition)
1229     Record.AddDeclRef(Context.getCurrentKeyFunction(D));
1230 
1231   Code = serialization::DECL_CXX_RECORD;
1232 }
1233 
1234 void ASTDeclWriter::VisitCXXMethodDecl(CXXMethodDecl *D) {
1235   VisitFunctionDecl(D);
1236   if (D->isCanonicalDecl()) {
1237     Record.push_back(D->size_overridden_methods());
1238     for (CXXMethodDecl::method_iterator
1239            I = D->begin_overridden_methods(), E = D->end_overridden_methods();
1240            I != E; ++I)
1241       Record.AddDeclRef(*I);
1242   } else {
1243     // We only need to record overridden methods once for the canonical decl.
1244     Record.push_back(0);
1245   }
1246 
1247   if (D->getDeclContext() == D->getLexicalDeclContext() &&
1248       D->getFirstDecl() == D->getMostRecentDecl() &&
1249       !D->isInvalidDecl() &&
1250       !D->hasAttrs() &&
1251       !D->isTopLevelDeclInObjCContainer() &&
1252       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
1253       !D->hasExtInfo() &&
1254       !D->hasInheritedPrototype() &&
1255       D->hasWrittenPrototype())
1256     AbbrevToUse = Writer.getDeclCXXMethodAbbrev();
1257 
1258   Code = serialization::DECL_CXX_METHOD;
1259 }
1260 
1261 void ASTDeclWriter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
1262   if (auto Inherited = D->getInheritedConstructor()) {
1263     Record.AddDeclRef(Inherited.getShadowDecl());
1264     Record.AddDeclRef(Inherited.getConstructor());
1265     Code = serialization::DECL_CXX_INHERITED_CONSTRUCTOR;
1266   } else {
1267     Code = serialization::DECL_CXX_CONSTRUCTOR;
1268   }
1269 
1270   VisitCXXMethodDecl(D);
1271 
1272   Record.push_back(D->IsExplicitSpecified);
1273 
1274   Code = D->isInheritingConstructor()
1275              ? serialization::DECL_CXX_INHERITED_CONSTRUCTOR
1276              : serialization::DECL_CXX_CONSTRUCTOR;
1277 }
1278 
1279 void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
1280   VisitCXXMethodDecl(D);
1281 
1282   Record.AddDeclRef(D->getOperatorDelete());
1283 
1284   Code = serialization::DECL_CXX_DESTRUCTOR;
1285 }
1286 
1287 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
1288   VisitCXXMethodDecl(D);
1289   Record.push_back(D->IsExplicitSpecified);
1290   Code = serialization::DECL_CXX_CONVERSION;
1291 }
1292 
1293 void ASTDeclWriter::VisitImportDecl(ImportDecl *D) {
1294   VisitDecl(D);
1295   Record.push_back(Writer.getSubmoduleID(D->getImportedModule()));
1296   ArrayRef<SourceLocation> IdentifierLocs = D->getIdentifierLocs();
1297   Record.push_back(!IdentifierLocs.empty());
1298   if (IdentifierLocs.empty()) {
1299     Record.AddSourceLocation(D->getLocEnd());
1300     Record.push_back(1);
1301   } else {
1302     for (unsigned I = 0, N = IdentifierLocs.size(); I != N; ++I)
1303       Record.AddSourceLocation(IdentifierLocs[I]);
1304     Record.push_back(IdentifierLocs.size());
1305   }
1306   // Note: the number of source locations must always be the last element in
1307   // the record.
1308   Code = serialization::DECL_IMPORT;
1309 }
1310 
1311 void ASTDeclWriter::VisitAccessSpecDecl(AccessSpecDecl *D) {
1312   VisitDecl(D);
1313   Record.AddSourceLocation(D->getColonLoc());
1314   Code = serialization::DECL_ACCESS_SPEC;
1315 }
1316 
1317 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
1318   // Record the number of friend type template parameter lists here
1319   // so as to simplify memory allocation during deserialization.
1320   Record.push_back(D->NumTPLists);
1321   VisitDecl(D);
1322   bool hasFriendDecl = D->Friend.is<NamedDecl*>();
1323   Record.push_back(hasFriendDecl);
1324   if (hasFriendDecl)
1325     Record.AddDeclRef(D->getFriendDecl());
1326   else
1327     Record.AddTypeSourceInfo(D->getFriendType());
1328   for (unsigned i = 0; i < D->NumTPLists; ++i)
1329     Record.AddTemplateParameterList(D->getFriendTypeTemplateParameterList(i));
1330   Record.AddDeclRef(D->getNextFriend());
1331   Record.push_back(D->UnsupportedFriend);
1332   Record.AddSourceLocation(D->FriendLoc);
1333   Code = serialization::DECL_FRIEND;
1334 }
1335 
1336 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
1337   VisitDecl(D);
1338   Record.push_back(D->getNumTemplateParameters());
1339   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
1340     Record.AddTemplateParameterList(D->getTemplateParameterList(i));
1341   Record.push_back(D->getFriendDecl() != nullptr);
1342   if (D->getFriendDecl())
1343     Record.AddDeclRef(D->getFriendDecl());
1344   else
1345     Record.AddTypeSourceInfo(D->getFriendType());
1346   Record.AddSourceLocation(D->getFriendLoc());
1347   Code = serialization::DECL_FRIEND_TEMPLATE;
1348 }
1349 
1350 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
1351   VisitNamedDecl(D);
1352 
1353   Record.AddDeclRef(D->getTemplatedDecl());
1354   Record.AddTemplateParameterList(D->getTemplateParameters());
1355 }
1356 
1357 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
1358   VisitRedeclarable(D);
1359 
1360   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
1361   // getCommonPtr() can be used while this is still initializing.
1362   if (D->isFirstDecl()) {
1363     // This declaration owns the 'common' pointer, so serialize that data now.
1364     Record.AddDeclRef(D->getInstantiatedFromMemberTemplate());
1365     if (D->getInstantiatedFromMemberTemplate())
1366       Record.push_back(D->isMemberSpecialization());
1367   }
1368 
1369   VisitTemplateDecl(D);
1370   Record.push_back(D->getIdentifierNamespace());
1371 }
1372 
1373 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1374   VisitRedeclarableTemplateDecl(D);
1375 
1376   if (D->isFirstDecl())
1377     AddTemplateSpecializations(D);
1378   Code = serialization::DECL_CLASS_TEMPLATE;
1379 }
1380 
1381 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
1382                                            ClassTemplateSpecializationDecl *D) {
1383   RegisterTemplateSpecialization(D->getSpecializedTemplate(), D);
1384 
1385   VisitCXXRecordDecl(D);
1386 
1387   llvm::PointerUnion<ClassTemplateDecl *,
1388                      ClassTemplatePartialSpecializationDecl *> InstFrom
1389     = D->getSpecializedTemplateOrPartial();
1390   if (Decl *InstFromD = InstFrom.dyn_cast<ClassTemplateDecl *>()) {
1391     Record.AddDeclRef(InstFromD);
1392   } else {
1393     Record.AddDeclRef(InstFrom.get<ClassTemplatePartialSpecializationDecl *>());
1394     Record.AddTemplateArgumentList(&D->getTemplateInstantiationArgs());
1395   }
1396 
1397   Record.AddTemplateArgumentList(&D->getTemplateArgs());
1398   Record.AddSourceLocation(D->getPointOfInstantiation());
1399   Record.push_back(D->getSpecializationKind());
1400   Record.push_back(D->isCanonicalDecl());
1401 
1402   if (D->isCanonicalDecl()) {
1403     // When reading, we'll add it to the folding set of the following template.
1404     Record.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl());
1405   }
1406 
1407   // Explicit info.
1408   Record.AddTypeSourceInfo(D->getTypeAsWritten());
1409   if (D->getTypeAsWritten()) {
1410     Record.AddSourceLocation(D->getExternLoc());
1411     Record.AddSourceLocation(D->getTemplateKeywordLoc());
1412   }
1413 
1414   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
1415 }
1416 
1417 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
1418                                     ClassTemplatePartialSpecializationDecl *D) {
1419   VisitClassTemplateSpecializationDecl(D);
1420 
1421   Record.AddTemplateParameterList(D->getTemplateParameters());
1422   Record.AddASTTemplateArgumentListInfo(D->getTemplateArgsAsWritten());
1423 
1424   // These are read/set from/to the first declaration.
1425   if (D->getPreviousDecl() == nullptr) {
1426     Record.AddDeclRef(D->getInstantiatedFromMember());
1427     Record.push_back(D->isMemberSpecialization());
1428   }
1429 
1430   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
1431 }
1432 
1433 void ASTDeclWriter::VisitVarTemplateDecl(VarTemplateDecl *D) {
1434   VisitRedeclarableTemplateDecl(D);
1435 
1436   if (D->isFirstDecl())
1437     AddTemplateSpecializations(D);
1438   Code = serialization::DECL_VAR_TEMPLATE;
1439 }
1440 
1441 void ASTDeclWriter::VisitVarTemplateSpecializationDecl(
1442     VarTemplateSpecializationDecl *D) {
1443   RegisterTemplateSpecialization(D->getSpecializedTemplate(), D);
1444 
1445   VisitVarDecl(D);
1446 
1447   llvm::PointerUnion<VarTemplateDecl *, VarTemplatePartialSpecializationDecl *>
1448   InstFrom = D->getSpecializedTemplateOrPartial();
1449   if (Decl *InstFromD = InstFrom.dyn_cast<VarTemplateDecl *>()) {
1450     Record.AddDeclRef(InstFromD);
1451   } else {
1452     Record.AddDeclRef(InstFrom.get<VarTemplatePartialSpecializationDecl *>());
1453     Record.AddTemplateArgumentList(&D->getTemplateInstantiationArgs());
1454   }
1455 
1456   // Explicit info.
1457   Record.AddTypeSourceInfo(D->getTypeAsWritten());
1458   if (D->getTypeAsWritten()) {
1459     Record.AddSourceLocation(D->getExternLoc());
1460     Record.AddSourceLocation(D->getTemplateKeywordLoc());
1461   }
1462 
1463   Record.AddTemplateArgumentList(&D->getTemplateArgs());
1464   Record.AddSourceLocation(D->getPointOfInstantiation());
1465   Record.push_back(D->getSpecializationKind());
1466   Record.push_back(D->isCanonicalDecl());
1467 
1468   if (D->isCanonicalDecl()) {
1469     // When reading, we'll add it to the folding set of the following template.
1470     Record.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl());
1471   }
1472 
1473   Code = serialization::DECL_VAR_TEMPLATE_SPECIALIZATION;
1474 }
1475 
1476 void ASTDeclWriter::VisitVarTemplatePartialSpecializationDecl(
1477     VarTemplatePartialSpecializationDecl *D) {
1478   VisitVarTemplateSpecializationDecl(D);
1479 
1480   Record.AddTemplateParameterList(D->getTemplateParameters());
1481   Record.AddASTTemplateArgumentListInfo(D->getTemplateArgsAsWritten());
1482 
1483   // These are read/set from/to the first declaration.
1484   if (D->getPreviousDecl() == nullptr) {
1485     Record.AddDeclRef(D->getInstantiatedFromMember());
1486     Record.push_back(D->isMemberSpecialization());
1487   }
1488 
1489   Code = serialization::DECL_VAR_TEMPLATE_PARTIAL_SPECIALIZATION;
1490 }
1491 
1492 void ASTDeclWriter::VisitClassScopeFunctionSpecializationDecl(
1493                                     ClassScopeFunctionSpecializationDecl *D) {
1494   VisitDecl(D);
1495   Record.AddDeclRef(D->getSpecialization());
1496   Code = serialization::DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION;
1497 }
1498 
1499 
1500 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1501   VisitRedeclarableTemplateDecl(D);
1502 
1503   if (D->isFirstDecl())
1504     AddTemplateSpecializations(D);
1505   Code = serialization::DECL_FUNCTION_TEMPLATE;
1506 }
1507 
1508 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1509   VisitTypeDecl(D);
1510 
1511   Record.push_back(D->wasDeclaredWithTypename());
1512 
1513   bool OwnsDefaultArg = D->hasDefaultArgument() &&
1514                         !D->defaultArgumentWasInherited();
1515   Record.push_back(OwnsDefaultArg);
1516   if (OwnsDefaultArg)
1517     Record.AddTypeSourceInfo(D->getDefaultArgumentInfo());
1518 
1519   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1520 }
1521 
1522 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1523   // For an expanded parameter pack, record the number of expansion types here
1524   // so that it's easier for deserialization to allocate the right amount of
1525   // memory.
1526   if (D->isExpandedParameterPack())
1527     Record.push_back(D->getNumExpansionTypes());
1528 
1529   VisitDeclaratorDecl(D);
1530   // TemplateParmPosition.
1531   Record.push_back(D->getDepth());
1532   Record.push_back(D->getPosition());
1533 
1534   if (D->isExpandedParameterPack()) {
1535     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1536       Record.AddTypeRef(D->getExpansionType(I));
1537       Record.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I));
1538     }
1539 
1540     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1541   } else {
1542     // Rest of NonTypeTemplateParmDecl.
1543     Record.push_back(D->isParameterPack());
1544     bool OwnsDefaultArg = D->hasDefaultArgument() &&
1545                           !D->defaultArgumentWasInherited();
1546     Record.push_back(OwnsDefaultArg);
1547     if (OwnsDefaultArg)
1548       Record.AddStmt(D->getDefaultArgument());
1549     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1550   }
1551 }
1552 
1553 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1554   // For an expanded parameter pack, record the number of expansion types here
1555   // so that it's easier for deserialization to allocate the right amount of
1556   // memory.
1557   if (D->isExpandedParameterPack())
1558     Record.push_back(D->getNumExpansionTemplateParameters());
1559 
1560   VisitTemplateDecl(D);
1561   // TemplateParmPosition.
1562   Record.push_back(D->getDepth());
1563   Record.push_back(D->getPosition());
1564 
1565   if (D->isExpandedParameterPack()) {
1566     for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
1567          I != N; ++I)
1568       Record.AddTemplateParameterList(D->getExpansionTemplateParameters(I));
1569     Code = serialization::DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK;
1570   } else {
1571     // Rest of TemplateTemplateParmDecl.
1572     Record.push_back(D->isParameterPack());
1573     bool OwnsDefaultArg = D->hasDefaultArgument() &&
1574                           !D->defaultArgumentWasInherited();
1575     Record.push_back(OwnsDefaultArg);
1576     if (OwnsDefaultArg)
1577       Record.AddTemplateArgumentLoc(D->getDefaultArgument());
1578     Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1579   }
1580 }
1581 
1582 void ASTDeclWriter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
1583   VisitRedeclarableTemplateDecl(D);
1584   Code = serialization::DECL_TYPE_ALIAS_TEMPLATE;
1585 }
1586 
1587 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1588   VisitDecl(D);
1589   Record.AddStmt(D->getAssertExpr());
1590   Record.push_back(D->isFailed());
1591   Record.AddStmt(D->getMessage());
1592   Record.AddSourceLocation(D->getRParenLoc());
1593   Code = serialization::DECL_STATIC_ASSERT;
1594 }
1595 
1596 /// \brief Emit the DeclContext part of a declaration context decl.
1597 void ASTDeclWriter::VisitDeclContext(DeclContext *DC) {
1598   Record.AddOffset(Writer.WriteDeclContextLexicalBlock(Context, DC));
1599   Record.AddOffset(Writer.WriteDeclContextVisibleBlock(Context, DC));
1600 }
1601 
1602 const Decl *ASTWriter::getFirstLocalDecl(const Decl *D) {
1603   assert(IsLocalDecl(D) && "expected a local declaration");
1604 
1605   const Decl *Canon = D->getCanonicalDecl();
1606   if (IsLocalDecl(Canon))
1607     return Canon;
1608 
1609   const Decl *&CacheEntry = FirstLocalDeclCache[Canon];
1610   if (CacheEntry)
1611     return CacheEntry;
1612 
1613   for (const Decl *Redecl = D; Redecl; Redecl = Redecl->getPreviousDecl())
1614     if (IsLocalDecl(Redecl))
1615       D = Redecl;
1616   return CacheEntry = D;
1617 }
1618 
1619 template <typename T>
1620 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1621   T *First = D->getFirstDecl();
1622   T *MostRecent = First->getMostRecentDecl();
1623   T *DAsT = static_cast<T *>(D);
1624   if (MostRecent != First) {
1625     assert(isRedeclarableDeclKind(DAsT->getKind()) &&
1626            "Not considered redeclarable?");
1627 
1628     Record.AddDeclRef(First);
1629 
1630     // Write out a list of local redeclarations of this declaration if it's the
1631     // first local declaration in the chain.
1632     const Decl *FirstLocal = Writer.getFirstLocalDecl(DAsT);
1633     if (DAsT == FirstLocal) {
1634       // Emit a list of all imported first declarations so that we can be sure
1635       // that all redeclarations visible to this module are before D in the
1636       // redecl chain.
1637       unsigned I = Record.size();
1638       Record.push_back(0);
1639       if (Writer.Chain)
1640         AddFirstDeclFromEachModule(DAsT, /*IncludeLocal*/false);
1641       // This is the number of imported first declarations + 1.
1642       Record[I] = Record.size() - I;
1643 
1644       // Collect the set of local redeclarations of this declaration, from
1645       // newest to oldest.
1646       ASTWriter::RecordData LocalRedecls;
1647       ASTRecordWriter LocalRedeclWriter(Record, LocalRedecls);
1648       for (const Decl *Prev = FirstLocal->getMostRecentDecl();
1649            Prev != FirstLocal; Prev = Prev->getPreviousDecl())
1650         if (!Prev->isFromASTFile())
1651           LocalRedeclWriter.AddDeclRef(Prev);
1652 
1653       // If we have any redecls, write them now as a separate record preceding
1654       // the declaration itself.
1655       if (LocalRedecls.empty())
1656         Record.push_back(0);
1657       else
1658         Record.AddOffset(LocalRedeclWriter.Emit(LOCAL_REDECLARATIONS));
1659     } else {
1660       Record.push_back(0);
1661       Record.AddDeclRef(FirstLocal);
1662     }
1663 
1664     // Make sure that we serialize both the previous and the most-recent
1665     // declarations, which (transitively) ensures that all declarations in the
1666     // chain get serialized.
1667     //
1668     // FIXME: This is not correct; when we reach an imported declaration we
1669     // won't emit its previous declaration.
1670     (void)Writer.GetDeclRef(D->getPreviousDecl());
1671     (void)Writer.GetDeclRef(MostRecent);
1672   } else {
1673     // We use the sentinel value 0 to indicate an only declaration.
1674     Record.push_back(0);
1675   }
1676 }
1677 
1678 void ASTDeclWriter::VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D) {
1679   Record.push_back(D->varlist_size());
1680   VisitDecl(D);
1681   for (auto *I : D->varlists())
1682     Record.AddStmt(I);
1683   Code = serialization::DECL_OMP_THREADPRIVATE;
1684 }
1685 
1686 void ASTDeclWriter::VisitOMPDeclareReductionDecl(OMPDeclareReductionDecl *D) {
1687   VisitValueDecl(D);
1688   Record.AddSourceLocation(D->getLocStart());
1689   Record.AddStmt(D->getCombiner());
1690   Record.AddStmt(D->getInitializer());
1691   Record.AddDeclRef(D->getPrevDeclInScope());
1692   Code = serialization::DECL_OMP_DECLARE_REDUCTION;
1693 }
1694 
1695 void ASTDeclWriter::VisitOMPCapturedExprDecl(OMPCapturedExprDecl *D) {
1696   VisitVarDecl(D);
1697   Code = serialization::DECL_OMP_CAPTUREDEXPR;
1698 }
1699 
1700 //===----------------------------------------------------------------------===//
1701 // ASTWriter Implementation
1702 //===----------------------------------------------------------------------===//
1703 
1704 void ASTWriter::WriteDeclAbbrevs() {
1705   using namespace llvm;
1706 
1707   std::shared_ptr<BitCodeAbbrev> Abv;
1708 
1709   // Abbreviation for DECL_FIELD
1710   Abv = std::make_shared<BitCodeAbbrev>();
1711   Abv->Add(BitCodeAbbrevOp(serialization::DECL_FIELD));
1712   // Decl
1713   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1714   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1715   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1716   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1717   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1718   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1719   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1720   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1721   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1722   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1723   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1724   // NamedDecl
1725   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1726   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1727   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1728   // ValueDecl
1729   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1730   // DeclaratorDecl
1731   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1732   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1733   // FieldDecl
1734   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1735   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1736   // Type Source Info
1737   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1738   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1739   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1740   DeclFieldAbbrev = Stream.EmitAbbrev(std::move(Abv));
1741 
1742   // Abbreviation for DECL_OBJC_IVAR
1743   Abv = std::make_shared<BitCodeAbbrev>();
1744   Abv->Add(BitCodeAbbrevOp(serialization::DECL_OBJC_IVAR));
1745   // Decl
1746   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1747   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1748   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1749   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1750   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1751   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1752   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1753   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1754   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1755   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1756   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1757   // NamedDecl
1758   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1759   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1760   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1761   // ValueDecl
1762   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1763   // DeclaratorDecl
1764   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1765   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1766   // FieldDecl
1767   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1768   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1769   // ObjC Ivar
1770   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getAccessControl
1771   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getSynthesize
1772   // Type Source Info
1773   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1774   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1775   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1776   DeclObjCIvarAbbrev = Stream.EmitAbbrev(std::move(Abv));
1777 
1778   // Abbreviation for DECL_ENUM
1779   Abv = std::make_shared<BitCodeAbbrev>();
1780   Abv->Add(BitCodeAbbrevOp(serialization::DECL_ENUM));
1781   // Redeclarable
1782   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1783   // Decl
1784   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1785   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1786   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1787   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1788   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1789   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1790   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1791   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1792   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1793   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1794   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1795   // NamedDecl
1796   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1797   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1798   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1799   // TypeDecl
1800   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1801   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1802   // TagDecl
1803   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1804   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1805   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1806   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1807   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1808   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsCompleteDefinitionRequired
1809   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1810   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1811   Abv->Add(BitCodeAbbrevOp(0));                         // ExtInfoKind
1812   // EnumDecl
1813   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddTypeRef
1814   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IntegerType
1815   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getPromotionType
1816   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumPositiveBits
1817   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumNegativeBits
1818   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScoped
1819   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScopedUsingClassTag
1820   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isFixed
1821   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InstantiatedMembEnum
1822   // DC
1823   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1824   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1825   DeclEnumAbbrev = Stream.EmitAbbrev(std::move(Abv));
1826 
1827   // Abbreviation for DECL_RECORD
1828   Abv = std::make_shared<BitCodeAbbrev>();
1829   Abv->Add(BitCodeAbbrevOp(serialization::DECL_RECORD));
1830   // Redeclarable
1831   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1832   // Decl
1833   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1834   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1835   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1836   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1837   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1838   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1839   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1840   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1841   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1842   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1843   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1844   // NamedDecl
1845   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1846   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1847   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1848   // TypeDecl
1849   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1850   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1851   // TagDecl
1852   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1853   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1854   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1855   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1856   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1857   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsCompleteDefinitionRequired
1858   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1859   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1860   Abv->Add(BitCodeAbbrevOp(0));                         // ExtInfoKind
1861   // RecordDecl
1862   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // FlexibleArrayMember
1863   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // AnonymousStructUnion
1864   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasObjectMember
1865   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasVolatileMember
1866   // DC
1867   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1868   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1869   DeclRecordAbbrev = Stream.EmitAbbrev(std::move(Abv));
1870 
1871   // Abbreviation for DECL_PARM_VAR
1872   Abv = std::make_shared<BitCodeAbbrev>();
1873   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1874   // Redeclarable
1875   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1876   // Decl
1877   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1878   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1879   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1880   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1881   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1882   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1883   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1884   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1885   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1886   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1887   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1888   // NamedDecl
1889   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1890   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1891   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1892   // ValueDecl
1893   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1894   // DeclaratorDecl
1895   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1896   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1897   // VarDecl
1898   Abv->Add(BitCodeAbbrevOp(0));                       // SClass
1899   Abv->Add(BitCodeAbbrevOp(0));                       // TSCSpec
1900   Abv->Add(BitCodeAbbrevOp(0));                       // InitStyle
1901   Abv->Add(BitCodeAbbrevOp(0));                       // Linkage
1902   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
1903   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
1904   // ParmVarDecl
1905   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsObjCMethodParameter
1906   Abv->Add(BitCodeAbbrevOp(0));                       // ScopeDepth
1907   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ScopeIndex
1908   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
1909   Abv->Add(BitCodeAbbrevOp(0));                       // KNRPromoted
1910   Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
1911   Abv->Add(BitCodeAbbrevOp(0));                   // HasUninstantiatedDefaultArg
1912   // Type Source Info
1913   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1914   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1915   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1916   DeclParmVarAbbrev = Stream.EmitAbbrev(std::move(Abv));
1917 
1918   // Abbreviation for DECL_TYPEDEF
1919   Abv = std::make_shared<BitCodeAbbrev>();
1920   Abv->Add(BitCodeAbbrevOp(serialization::DECL_TYPEDEF));
1921   // Redeclarable
1922   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1923   // Decl
1924   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1925   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1926   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1927   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1928   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1929   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isUsed
1930   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isReferenced
1931   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1932   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // C++ AccessSpecifier
1933   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1934   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1935   // NamedDecl
1936   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1937   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1938   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1939   // TypeDecl
1940   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1941   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1942   // TypedefDecl
1943   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1944   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1945   DeclTypedefAbbrev = Stream.EmitAbbrev(std::move(Abv));
1946 
1947   // Abbreviation for DECL_VAR
1948   Abv = std::make_shared<BitCodeAbbrev>();
1949   Abv->Add(BitCodeAbbrevOp(serialization::DECL_VAR));
1950   // Redeclarable
1951   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1952   // Decl
1953   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1954   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1955   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1956   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1957   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1958   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1959   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1960   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1961   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1962   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1963   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1964   // NamedDecl
1965   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1966   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1967   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1968   // ValueDecl
1969   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1970   // DeclaratorDecl
1971   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1972   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1973   // VarDecl
1974   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // SClass
1975   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // TSCSpec
1976   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // InitStyle
1977   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsThisDeclarationADemotedDefinition
1978   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
1979   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
1980   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
1981   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
1982   Abv->Add(BitCodeAbbrevOp(0));                         // isInline
1983   Abv->Add(BitCodeAbbrevOp(0));                         // isInlineSpecified
1984   Abv->Add(BitCodeAbbrevOp(0));                         // isConstexpr
1985   Abv->Add(BitCodeAbbrevOp(0));                         // isInitCapture
1986   Abv->Add(BitCodeAbbrevOp(0));                         // isPrevDeclInSameScope
1987   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Linkage
1988   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // IsInitICE (local)
1989   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // VarKind (local enum)
1990   // Type Source Info
1991   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1992   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1993   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1994   DeclVarAbbrev = Stream.EmitAbbrev(std::move(Abv));
1995 
1996   // Abbreviation for DECL_CXX_METHOD
1997   Abv = std::make_shared<BitCodeAbbrev>();
1998   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CXX_METHOD));
1999   // RedeclarableDecl
2000   Abv->Add(BitCodeAbbrevOp(0));                         // CanonicalDecl
2001   // Decl
2002   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // DeclContext
2003   Abv->Add(BitCodeAbbrevOp(0));                         // LexicalDeclContext
2004   Abv->Add(BitCodeAbbrevOp(0));                         // Invalid
2005   Abv->Add(BitCodeAbbrevOp(0));                         // HasAttrs
2006   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Implicit
2007   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Used
2008   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Referenced
2009   Abv->Add(BitCodeAbbrevOp(0));                         // InObjCContainer
2010   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // Access
2011   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ModulePrivate
2012   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SubmoduleID
2013   // NamedDecl
2014   Abv->Add(BitCodeAbbrevOp(DeclarationName::Identifier)); // NameKind
2015   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Identifier
2016   Abv->Add(BitCodeAbbrevOp(0));                         // AnonDeclNumber
2017   // ValueDecl
2018   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Type
2019   // DeclaratorDecl
2020   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InnerLocStart
2021   Abv->Add(BitCodeAbbrevOp(0));                         // HasExtInfo
2022   // FunctionDecl
2023   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 11)); // IDNS
2024   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // StorageClass
2025   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Inline
2026   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InlineSpecified
2027   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // VirtualAsWritten
2028   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Pure
2029   Abv->Add(BitCodeAbbrevOp(0));                         // HasInheritedProto
2030   Abv->Add(BitCodeAbbrevOp(1));                         // HasWrittenProto
2031   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Deleted
2032   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Trivial
2033   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Defaulted
2034   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ExplicitlyDefaulted
2035   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ImplicitReturnZero
2036   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Constexpr
2037   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // UsesSEHTry
2038   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // SkippedBody
2039   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // LateParsed
2040   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Linkage
2041   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LocEnd
2042   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // TemplateKind
2043   // This Array slurps the rest of the record. Fortunately we want to encode
2044   // (nearly) all the remaining (variable number of) fields in the same way.
2045   //
2046   // This is the function template information if any, then
2047   //         NumParams and Params[] from FunctionDecl, and
2048   //         NumOverriddenMethods, OverriddenMethods[] from CXXMethodDecl.
2049   //
2050   //  Add an AbbrevOp for 'size then elements' and use it here.
2051   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2052   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
2053   DeclCXXMethodAbbrev = Stream.EmitAbbrev(std::move(Abv));
2054 
2055   // Abbreviation for EXPR_DECL_REF
2056   Abv = std::make_shared<BitCodeAbbrev>();
2057   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_DECL_REF));
2058   //Stmt
2059   //Expr
2060   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2061   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
2062   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
2063   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
2064   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
2065   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
2066   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
2067   //DeclRefExpr
2068   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HasQualifier
2069   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //GetDeclFound
2070   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ExplicitTemplateArgs
2071   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HadMultipleCandidates
2072   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
2073                            1)); // RefersToEnclosingVariableOrCapture
2074   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclRef
2075   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
2076   DeclRefExprAbbrev = Stream.EmitAbbrev(std::move(Abv));
2077 
2078   // Abbreviation for EXPR_INTEGER_LITERAL
2079   Abv = std::make_shared<BitCodeAbbrev>();
2080   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_INTEGER_LITERAL));
2081   //Stmt
2082   //Expr
2083   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2084   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
2085   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
2086   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
2087   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
2088   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
2089   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
2090   //Integer Literal
2091   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
2092   Abv->Add(BitCodeAbbrevOp(32));                      // Bit Width
2093   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Value
2094   IntegerLiteralAbbrev = Stream.EmitAbbrev(std::move(Abv));
2095 
2096   // Abbreviation for EXPR_CHARACTER_LITERAL
2097   Abv = std::make_shared<BitCodeAbbrev>();
2098   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_CHARACTER_LITERAL));
2099   //Stmt
2100   //Expr
2101   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2102   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
2103   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
2104   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
2105   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
2106   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
2107   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
2108   //Character Literal
2109   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getValue
2110   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
2111   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // getKind
2112   CharacterLiteralAbbrev = Stream.EmitAbbrev(std::move(Abv));
2113 
2114   // Abbreviation for EXPR_IMPLICIT_CAST
2115   Abv = std::make_shared<BitCodeAbbrev>();
2116   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_IMPLICIT_CAST));
2117   // Stmt
2118   // Expr
2119   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2120   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
2121   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
2122   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
2123   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
2124   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
2125   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
2126   // CastExpr
2127   Abv->Add(BitCodeAbbrevOp(0)); // PathSize
2128   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 6)); // CastKind
2129   // ImplicitCastExpr
2130   ExprImplicitCastAbbrev = Stream.EmitAbbrev(std::move(Abv));
2131 
2132   Abv = std::make_shared<BitCodeAbbrev>();
2133   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
2134   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2135   DeclContextLexicalAbbrev = Stream.EmitAbbrev(std::move(Abv));
2136 
2137   Abv = std::make_shared<BitCodeAbbrev>();
2138   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
2139   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2140   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(std::move(Abv));
2141 }
2142 
2143 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
2144 /// consumers of the AST.
2145 ///
2146 /// Such decls will always be deserialized from the AST file, so we would like
2147 /// this to be as restrictive as possible. Currently the predicate is driven by
2148 /// code generation requirements, if other clients have a different notion of
2149 /// what is "required" then we may have to consider an alternate scheme where
2150 /// clients can iterate over the top-level decls and get information on them,
2151 /// without necessary deserializing them. We could explicitly require such
2152 /// clients to use a separate API call to "realize" the decl. This should be
2153 /// relatively painless since they would presumably only do it for top-level
2154 /// decls.
2155 static bool isRequiredDecl(const Decl *D, ASTContext &Context,
2156                            bool WritingModule, bool ModularCode) {
2157   // An ObjCMethodDecl is never considered as "required" because its
2158   // implementation container always is.
2159 
2160   // File scoped assembly or obj-c or OMP declare target implementation must be
2161   // seen.
2162   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplDecl>(D) ||
2163       D->hasAttr<OMPDeclareTargetDeclAttr>())
2164     return true;
2165 
2166   if (WritingModule && (isa<VarDecl>(D) || isa<ImportDecl>(D))) {
2167     // These declarations are part of the module initializer, and are emitted
2168     // if and when the module is imported, rather than being emitted eagerly.
2169     return false;
2170   }
2171 
2172   return Context.DeclMustBeEmitted(D, ModularCode);
2173 }
2174 
2175 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
2176   // Determine the ID for this declaration.
2177   serialization::DeclID ID;
2178   assert(!D->isFromASTFile() && "should not be emitting imported decl");
2179   serialization::DeclID &IDR = DeclIDs[D];
2180   if (IDR == 0)
2181     IDR = NextDeclID++;
2182 
2183   ID = IDR;
2184 
2185   assert(ID >= FirstDeclID && "invalid decl ID");
2186 
2187   RecordData Record;
2188   ASTDeclWriter W(*this, Context, Record);
2189 
2190   // Build a record for this declaration
2191   W.Visit(D);
2192 
2193   // Emit this declaration to the bitstream.
2194   uint64_t Offset = W.Emit(D);
2195 
2196   // Record the offset for this declaration
2197   SourceLocation Loc = D->getLocation();
2198   unsigned Index = ID - FirstDeclID;
2199   if (DeclOffsets.size() == Index)
2200     DeclOffsets.push_back(DeclOffset(Loc, Offset));
2201   else if (DeclOffsets.size() < Index) {
2202     // FIXME: Can/should this happen?
2203     DeclOffsets.resize(Index+1);
2204     DeclOffsets[Index].setLocation(Loc);
2205     DeclOffsets[Index].BitOffset = Offset;
2206   } else {
2207     llvm_unreachable("declarations should be emitted in ID order");
2208   }
2209 
2210   SourceManager &SM = Context.getSourceManager();
2211   if (Loc.isValid() && SM.isLocalSourceLocation(Loc))
2212     associateDeclWithFile(D, ID);
2213 
2214   // Note declarations that should be deserialized eagerly so that we can add
2215   // them to a record in the AST file later.
2216   if (isRequiredDecl(D, Context, WritingModule, false))
2217     EagerlyDeserializedDecls.push_back(ID);
2218   else if (Context.getLangOpts().ModularCodegen && WritingModule &&
2219            isRequiredDecl(D, Context, true, true))
2220     ModularCodegenDecls.push_back(ID);
2221 }
2222 
2223 void ASTRecordWriter::AddFunctionDefinition(const FunctionDecl *FD) {
2224   // Switch case IDs are per function body.
2225   Writer->ClearSwitchCaseIDs();
2226 
2227   assert(FD->doesThisDeclarationHaveABody());
2228   if (auto *CD = dyn_cast<CXXConstructorDecl>(FD)) {
2229     Record->push_back(CD->getNumCtorInitializers());
2230     if (CD->getNumCtorInitializers())
2231       AddCXXCtorInitializers(
2232           llvm::makeArrayRef(CD->init_begin(), CD->init_end()));
2233   }
2234   AddStmt(FD->getBody());
2235 }
2236