1 //===--- ASTWriterDecl.cpp - Declaration Serialization --------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 //  This file implements serialization for Declarations.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Serialization/ASTWriter.h"
15 #include "clang/Serialization/ASTReader.h"
16 #include "ASTCommon.h"
17 #include "clang/AST/DeclVisitor.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/DeclTemplate.h"
20 #include "clang/AST/Expr.h"
21 #include "clang/AST/DeclContextInternals.h"
22 #include "clang/Basic/SourceManager.h"
23 #include "llvm/ADT/Twine.h"
24 #include "llvm/Bitcode/BitstreamWriter.h"
25 #include "llvm/Support/ErrorHandling.h"
26 using namespace clang;
27 using namespace serialization;
28 
29 //===----------------------------------------------------------------------===//
30 // Declaration serialization
31 //===----------------------------------------------------------------------===//
32 
33 namespace clang {
34   class ASTDeclWriter : public DeclVisitor<ASTDeclWriter, void> {
35 
36     ASTWriter &Writer;
37     ASTContext &Context;
38     typedef ASTWriter::RecordData RecordData;
39     RecordData &Record;
40 
41   public:
42     serialization::DeclCode Code;
43     unsigned AbbrevToUse;
44 
45     ASTDeclWriter(ASTWriter &Writer, ASTContext &Context, RecordData &Record)
46       : Writer(Writer), Context(Context), Record(Record) {
47     }
48 
49     void Visit(Decl *D);
50 
51     void VisitDecl(Decl *D);
52     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
53     void VisitNamedDecl(NamedDecl *D);
54     void VisitLabelDecl(LabelDecl *LD);
55     void VisitNamespaceDecl(NamespaceDecl *D);
56     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
57     void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
58     void VisitTypeDecl(TypeDecl *D);
59     void VisitTypedefNameDecl(TypedefNameDecl *D);
60     void VisitTypedefDecl(TypedefDecl *D);
61     void VisitTypeAliasDecl(TypeAliasDecl *D);
62     void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
63     void VisitTagDecl(TagDecl *D);
64     void VisitEnumDecl(EnumDecl *D);
65     void VisitRecordDecl(RecordDecl *D);
66     void VisitCXXRecordDecl(CXXRecordDecl *D);
67     void VisitClassTemplateSpecializationDecl(
68                                             ClassTemplateSpecializationDecl *D);
69     void VisitClassTemplatePartialSpecializationDecl(
70                                      ClassTemplatePartialSpecializationDecl *D);
71     void VisitClassScopeFunctionSpecializationDecl(
72                                        ClassScopeFunctionSpecializationDecl *D);
73     void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
74     void VisitValueDecl(ValueDecl *D);
75     void VisitEnumConstantDecl(EnumConstantDecl *D);
76     void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
77     void VisitDeclaratorDecl(DeclaratorDecl *D);
78     void VisitFunctionDecl(FunctionDecl *D);
79     void VisitCXXMethodDecl(CXXMethodDecl *D);
80     void VisitCXXConstructorDecl(CXXConstructorDecl *D);
81     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
82     void VisitCXXConversionDecl(CXXConversionDecl *D);
83     void VisitFieldDecl(FieldDecl *D);
84     void VisitIndirectFieldDecl(IndirectFieldDecl *D);
85     void VisitVarDecl(VarDecl *D);
86     void VisitImplicitParamDecl(ImplicitParamDecl *D);
87     void VisitParmVarDecl(ParmVarDecl *D);
88     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
89     void VisitTemplateDecl(TemplateDecl *D);
90     void VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
91     void VisitClassTemplateDecl(ClassTemplateDecl *D);
92     void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
93     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
94     void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
95     void VisitUsingDecl(UsingDecl *D);
96     void VisitUsingShadowDecl(UsingShadowDecl *D);
97     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
98     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
99     void VisitImportDecl(ImportDecl *D);
100     void VisitAccessSpecDecl(AccessSpecDecl *D);
101     void VisitFriendDecl(FriendDecl *D);
102     void VisitFriendTemplateDecl(FriendTemplateDecl *D);
103     void VisitStaticAssertDecl(StaticAssertDecl *D);
104     void VisitBlockDecl(BlockDecl *D);
105 
106     void VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
107                           uint64_t VisibleOffset);
108     template <typename T> void VisitRedeclarable(Redeclarable<T> *D);
109 
110 
111     // FIXME: Put in the same order is DeclNodes.td?
112     void VisitObjCMethodDecl(ObjCMethodDecl *D);
113     void VisitObjCContainerDecl(ObjCContainerDecl *D);
114     void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
115     void VisitObjCIvarDecl(ObjCIvarDecl *D);
116     void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
117     void VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D);
118     void VisitObjCCategoryDecl(ObjCCategoryDecl *D);
119     void VisitObjCImplDecl(ObjCImplDecl *D);
120     void VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D);
121     void VisitObjCImplementationDecl(ObjCImplementationDecl *D);
122     void VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D);
123     void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
124     void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
125   };
126 }
127 
128 void ASTDeclWriter::Visit(Decl *D) {
129   DeclVisitor<ASTDeclWriter>::Visit(D);
130 
131   // Source locations require array (variable-length) abbreviations.  The
132   // abbreviation infrastructure requires that arrays are encoded last, so
133   // we handle it here in the case of those classes derived from DeclaratorDecl
134   if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)){
135     Writer.AddTypeSourceInfo(DD->getTypeSourceInfo(), Record);
136   }
137 
138   // Handle FunctionDecl's body here and write it after all other Stmts/Exprs
139   // have been written. We want it last because we will not read it back when
140   // retrieving it from the AST, we'll just lazily set the offset.
141   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
142     Record.push_back(FD->doesThisDeclarationHaveABody());
143     if (FD->doesThisDeclarationHaveABody())
144       Writer.AddStmt(FD->getBody());
145   }
146 }
147 
148 void ASTDeclWriter::VisitDecl(Decl *D) {
149   Writer.AddDeclRef(cast_or_null<Decl>(D->getDeclContext()), Record);
150   Writer.AddDeclRef(cast_or_null<Decl>(D->getLexicalDeclContext()), Record);
151   Record.push_back(D->isInvalidDecl());
152   Record.push_back(D->hasAttrs());
153   if (D->hasAttrs())
154     Writer.WriteAttributes(ArrayRef<const Attr*>(D->getAttrs().begin(),
155                                                  D->getAttrs().size()), Record);
156   Record.push_back(D->isImplicit());
157   Record.push_back(D->isUsed(false));
158   Record.push_back(D->isReferenced());
159   Record.push_back(D->isTopLevelDeclInObjCContainer());
160   Record.push_back(D->getAccess());
161   Record.push_back(D->isModulePrivate());
162   Record.push_back(Writer.inferSubmoduleIDFromLocation(D->getLocation()));
163 }
164 
165 void ASTDeclWriter::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
166   llvm_unreachable("Translation units aren't directly serialized");
167 }
168 
169 void ASTDeclWriter::VisitNamedDecl(NamedDecl *D) {
170   VisitDecl(D);
171   Writer.AddDeclarationName(D->getDeclName(), Record);
172 }
173 
174 void ASTDeclWriter::VisitTypeDecl(TypeDecl *D) {
175   VisitNamedDecl(D);
176   Writer.AddSourceLocation(D->getLocStart(), Record);
177   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
178 }
179 
180 void ASTDeclWriter::VisitTypedefNameDecl(TypedefNameDecl *D) {
181   VisitRedeclarable(D);
182   VisitTypeDecl(D);
183   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
184 }
185 
186 void ASTDeclWriter::VisitTypedefDecl(TypedefDecl *D) {
187   VisitTypedefNameDecl(D);
188   if (!D->hasAttrs() &&
189       !D->isImplicit() &&
190       !D->isUsed(false) &&
191       D->getFirstDeclaration() == D->getMostRecentDecl() &&
192       !D->isInvalidDecl() &&
193       !D->isReferenced() &&
194       !D->isTopLevelDeclInObjCContainer() &&
195       D->getAccess() == AS_none &&
196       !D->isModulePrivate() &&
197       D->getDeclName().getNameKind() == DeclarationName::Identifier)
198     AbbrevToUse = Writer.getDeclTypedefAbbrev();
199 
200   Code = serialization::DECL_TYPEDEF;
201 }
202 
203 void ASTDeclWriter::VisitTypeAliasDecl(TypeAliasDecl *D) {
204   VisitTypedefNameDecl(D);
205   Code = serialization::DECL_TYPEALIAS;
206 }
207 
208 void ASTDeclWriter::VisitTagDecl(TagDecl *D) {
209   VisitRedeclarable(D);
210   VisitTypeDecl(D);
211   Record.push_back(D->getIdentifierNamespace());
212   Record.push_back((unsigned)D->getTagKind()); // FIXME: stable encoding
213   Record.push_back(D->isCompleteDefinition());
214   Record.push_back(D->isEmbeddedInDeclarator());
215   Record.push_back(D->isFreeStanding());
216   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
217   Record.push_back(D->hasExtInfo());
218   if (D->hasExtInfo())
219     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
220   else
221     Writer.AddDeclRef(D->getTypedefNameForAnonDecl(), Record);
222 }
223 
224 void ASTDeclWriter::VisitEnumDecl(EnumDecl *D) {
225   VisitTagDecl(D);
226   Writer.AddTypeSourceInfo(D->getIntegerTypeSourceInfo(), Record);
227   if (!D->getIntegerTypeSourceInfo())
228     Writer.AddTypeRef(D->getIntegerType(), Record);
229   Writer.AddTypeRef(D->getPromotionType(), Record);
230   Record.push_back(D->getNumPositiveBits());
231   Record.push_back(D->getNumNegativeBits());
232   Record.push_back(D->isScoped());
233   Record.push_back(D->isScopedUsingClassTag());
234   Record.push_back(D->isFixed());
235   if (MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo()) {
236     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
237     Record.push_back(MemberInfo->getTemplateSpecializationKind());
238     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
239   } else {
240     Writer.AddDeclRef(0, Record);
241   }
242 
243   if (!D->hasAttrs() &&
244       !D->isImplicit() &&
245       !D->isUsed(false) &&
246       !D->hasExtInfo() &&
247       D->getFirstDeclaration() == D->getMostRecentDecl() &&
248       !D->isInvalidDecl() &&
249       !D->isReferenced() &&
250       !D->isTopLevelDeclInObjCContainer() &&
251       D->getAccess() == AS_none &&
252       !D->isModulePrivate() &&
253       !CXXRecordDecl::classofKind(D->getKind()) &&
254       !D->getIntegerTypeSourceInfo() &&
255       D->getDeclName().getNameKind() == DeclarationName::Identifier)
256     AbbrevToUse = Writer.getDeclEnumAbbrev();
257 
258   Code = serialization::DECL_ENUM;
259 }
260 
261 void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
262   VisitTagDecl(D);
263   Record.push_back(D->hasFlexibleArrayMember());
264   Record.push_back(D->isAnonymousStructOrUnion());
265   Record.push_back(D->hasObjectMember());
266 
267   if (!D->hasAttrs() &&
268       !D->isImplicit() &&
269       !D->isUsed(false) &&
270       !D->hasExtInfo() &&
271       D->getFirstDeclaration() == D->getMostRecentDecl() &&
272       !D->isInvalidDecl() &&
273       !D->isReferenced() &&
274       !D->isTopLevelDeclInObjCContainer() &&
275       D->getAccess() == AS_none &&
276       !D->isModulePrivate() &&
277       !CXXRecordDecl::classofKind(D->getKind()) &&
278       D->getDeclName().getNameKind() == DeclarationName::Identifier)
279     AbbrevToUse = Writer.getDeclRecordAbbrev();
280 
281   Code = serialization::DECL_RECORD;
282 }
283 
284 void ASTDeclWriter::VisitValueDecl(ValueDecl *D) {
285   VisitNamedDecl(D);
286   Writer.AddTypeRef(D->getType(), Record);
287 }
288 
289 void ASTDeclWriter::VisitEnumConstantDecl(EnumConstantDecl *D) {
290   VisitValueDecl(D);
291   Record.push_back(D->getInitExpr()? 1 : 0);
292   if (D->getInitExpr())
293     Writer.AddStmt(D->getInitExpr());
294   Writer.AddAPSInt(D->getInitVal(), Record);
295 
296   Code = serialization::DECL_ENUM_CONSTANT;
297 }
298 
299 void ASTDeclWriter::VisitDeclaratorDecl(DeclaratorDecl *D) {
300   VisitValueDecl(D);
301   Writer.AddSourceLocation(D->getInnerLocStart(), Record);
302   Record.push_back(D->hasExtInfo());
303   if (D->hasExtInfo())
304     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
305 }
306 
307 void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
308   VisitRedeclarable(D);
309   VisitDeclaratorDecl(D);
310 
311   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
312   Record.push_back(D->getIdentifierNamespace());
313 
314   // FunctionDecl's body is handled last at ASTWriterDecl::Visit,
315   // after everything else is written.
316 
317   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
318   Record.push_back(D->getStorageClassAsWritten());
319   Record.push_back(D->IsInline);
320   Record.push_back(D->isInlineSpecified());
321   Record.push_back(D->isVirtualAsWritten());
322   Record.push_back(D->isPure());
323   Record.push_back(D->hasInheritedPrototype());
324   Record.push_back(D->hasWrittenPrototype());
325   Record.push_back(D->isDeletedAsWritten());
326   Record.push_back(D->isTrivial());
327   Record.push_back(D->isDefaulted());
328   Record.push_back(D->isExplicitlyDefaulted());
329   Record.push_back(D->hasImplicitReturnZero());
330   Record.push_back(D->isConstexpr());
331   Writer.AddSourceLocation(D->getLocEnd(), Record);
332 
333   Record.push_back(D->getTemplatedKind());
334   switch (D->getTemplatedKind()) {
335   case FunctionDecl::TK_NonTemplate:
336     break;
337   case FunctionDecl::TK_FunctionTemplate:
338     Writer.AddDeclRef(D->getDescribedFunctionTemplate(), Record);
339     break;
340   case FunctionDecl::TK_MemberSpecialization: {
341     MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo();
342     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
343     Record.push_back(MemberInfo->getTemplateSpecializationKind());
344     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
345     break;
346   }
347   case FunctionDecl::TK_FunctionTemplateSpecialization: {
348     FunctionTemplateSpecializationInfo *
349       FTSInfo = D->getTemplateSpecializationInfo();
350     Writer.AddDeclRef(FTSInfo->getTemplate(), Record);
351     Record.push_back(FTSInfo->getTemplateSpecializationKind());
352 
353     // Template arguments.
354     Writer.AddTemplateArgumentList(FTSInfo->TemplateArguments, Record);
355 
356     // Template args as written.
357     Record.push_back(FTSInfo->TemplateArgumentsAsWritten != 0);
358     if (FTSInfo->TemplateArgumentsAsWritten) {
359       Record.push_back(FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs);
360       for (int i=0, e = FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs;
361              i!=e; ++i)
362         Writer.AddTemplateArgumentLoc((*FTSInfo->TemplateArgumentsAsWritten)[i],
363                                       Record);
364       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->LAngleLoc,
365                                Record);
366       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->RAngleLoc,
367                                Record);
368     }
369 
370     Writer.AddSourceLocation(FTSInfo->getPointOfInstantiation(), Record);
371 
372     if (D->isCanonicalDecl()) {
373       // Write the template that contains the specializations set. We will
374       // add a FunctionTemplateSpecializationInfo to it when reading.
375       Writer.AddDeclRef(FTSInfo->getTemplate()->getCanonicalDecl(), Record);
376     }
377     break;
378   }
379   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
380     DependentFunctionTemplateSpecializationInfo *
381       DFTSInfo = D->getDependentSpecializationInfo();
382 
383     // Templates.
384     Record.push_back(DFTSInfo->getNumTemplates());
385     for (int i=0, e = DFTSInfo->getNumTemplates(); i != e; ++i)
386       Writer.AddDeclRef(DFTSInfo->getTemplate(i), Record);
387 
388     // Templates args.
389     Record.push_back(DFTSInfo->getNumTemplateArgs());
390     for (int i=0, e = DFTSInfo->getNumTemplateArgs(); i != e; ++i)
391       Writer.AddTemplateArgumentLoc(DFTSInfo->getTemplateArg(i), Record);
392     Writer.AddSourceLocation(DFTSInfo->getLAngleLoc(), Record);
393     Writer.AddSourceLocation(DFTSInfo->getRAngleLoc(), Record);
394     break;
395   }
396   }
397 
398   Record.push_back(D->param_size());
399   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
400        P != PEnd; ++P)
401     Writer.AddDeclRef(*P, Record);
402   Code = serialization::DECL_FUNCTION;
403 }
404 
405 void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
406   VisitNamedDecl(D);
407   // FIXME: convert to LazyStmtPtr?
408   // Unlike C/C++, method bodies will never be in header files.
409   bool HasBodyStuff = D->getBody() != 0     ||
410                       D->getSelfDecl() != 0 || D->getCmdDecl() != 0;
411   Record.push_back(HasBodyStuff);
412   if (HasBodyStuff) {
413     Writer.AddStmt(D->getBody());
414     Writer.AddDeclRef(D->getSelfDecl(), Record);
415     Writer.AddDeclRef(D->getCmdDecl(), Record);
416   }
417   Record.push_back(D->isInstanceMethod());
418   Record.push_back(D->isVariadic());
419   Record.push_back(D->isSynthesized());
420   Record.push_back(D->isDefined());
421   Record.push_back(D->IsOverriding);
422 
423   Record.push_back(D->IsRedeclaration);
424   Record.push_back(D->HasRedeclaration);
425   if (D->HasRedeclaration) {
426     assert(Context.getObjCMethodRedeclaration(D));
427     Writer.AddDeclRef(Context.getObjCMethodRedeclaration(D), Record);
428   }
429 
430   // FIXME: stable encoding for @required/@optional
431   Record.push_back(D->getImplementationControl());
432   // FIXME: stable encoding for in/out/inout/bycopy/byref/oneway
433   Record.push_back(D->getObjCDeclQualifier());
434   Record.push_back(D->hasRelatedResultType());
435   Writer.AddTypeRef(D->getResultType(), Record);
436   Writer.AddTypeSourceInfo(D->getResultTypeSourceInfo(), Record);
437   Writer.AddSourceLocation(D->getLocEnd(), Record);
438   Record.push_back(D->param_size());
439   for (ObjCMethodDecl::param_iterator P = D->param_begin(),
440                                    PEnd = D->param_end(); P != PEnd; ++P)
441     Writer.AddDeclRef(*P, Record);
442 
443   Record.push_back(D->SelLocsKind);
444   unsigned NumStoredSelLocs = D->getNumStoredSelLocs();
445   SourceLocation *SelLocs = D->getStoredSelLocs();
446   Record.push_back(NumStoredSelLocs);
447   for (unsigned i = 0; i != NumStoredSelLocs; ++i)
448     Writer.AddSourceLocation(SelLocs[i], Record);
449 
450   Code = serialization::DECL_OBJC_METHOD;
451 }
452 
453 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
454   VisitNamedDecl(D);
455   Writer.AddSourceLocation(D->getAtStartLoc(), Record);
456   Writer.AddSourceRange(D->getAtEndRange(), Record);
457   // Abstract class (no need to define a stable serialization::DECL code).
458 }
459 
460 void ASTDeclWriter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
461   VisitRedeclarable(D);
462   VisitObjCContainerDecl(D);
463   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
464 
465   Record.push_back(D->isThisDeclarationADefinition());
466   if (D->isThisDeclarationADefinition()) {
467     // Write the DefinitionData
468     ObjCInterfaceDecl::DefinitionData &Data = D->data();
469 
470     Writer.AddDeclRef(D->getSuperClass(), Record);
471     Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
472     Writer.AddSourceLocation(D->getEndOfDefinitionLoc(), Record);
473 
474     // Write out the protocols that are directly referenced by the @interface.
475     Record.push_back(Data.ReferencedProtocols.size());
476     for (ObjCInterfaceDecl::protocol_iterator P = D->protocol_begin(),
477                                            PEnd = D->protocol_end();
478          P != PEnd; ++P)
479       Writer.AddDeclRef(*P, Record);
480     for (ObjCInterfaceDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
481          PLEnd = D->protocol_loc_end();
482          PL != PLEnd; ++PL)
483       Writer.AddSourceLocation(*PL, Record);
484 
485     // Write out the protocols that are transitively referenced.
486     Record.push_back(Data.AllReferencedProtocols.size());
487     for (ObjCList<ObjCProtocolDecl>::iterator
488               P = Data.AllReferencedProtocols.begin(),
489            PEnd = Data.AllReferencedProtocols.end();
490          P != PEnd; ++P)
491       Writer.AddDeclRef(*P, Record);
492 
493     if (ObjCCategoryDecl *Cat = D->getCategoryList()) {
494       // Ensure that we write out the set of categories for this class.
495       Writer.ObjCClassesWithCategories.insert(D);
496 
497       // Make sure that the categories get serialized.
498       for (; Cat; Cat = Cat->getNextClassCategory())
499         (void)Writer.GetDeclRef(Cat);
500     }
501   }
502 
503   Code = serialization::DECL_OBJC_INTERFACE;
504 }
505 
506 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
507   VisitFieldDecl(D);
508   // FIXME: stable encoding for @public/@private/@protected/@package
509   Record.push_back(D->getAccessControl());
510   Record.push_back(D->getSynthesize());
511 
512   if (!D->hasAttrs() &&
513       !D->isImplicit() &&
514       !D->isUsed(false) &&
515       !D->isInvalidDecl() &&
516       !D->isReferenced() &&
517       !D->isModulePrivate() &&
518       !D->getBitWidth() &&
519       !D->hasExtInfo() &&
520       D->getDeclName())
521     AbbrevToUse = Writer.getDeclObjCIvarAbbrev();
522 
523   Code = serialization::DECL_OBJC_IVAR;
524 }
525 
526 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
527   VisitRedeclarable(D);
528   VisitObjCContainerDecl(D);
529 
530   Record.push_back(D->isThisDeclarationADefinition());
531   if (D->isThisDeclarationADefinition()) {
532     Record.push_back(D->protocol_size());
533     for (ObjCProtocolDecl::protocol_iterator
534          I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
535       Writer.AddDeclRef(*I, Record);
536     for (ObjCProtocolDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
537            PLEnd = D->protocol_loc_end();
538          PL != PLEnd; ++PL)
539       Writer.AddSourceLocation(*PL, Record);
540   }
541 
542   Code = serialization::DECL_OBJC_PROTOCOL;
543 }
544 
545 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
546   VisitFieldDecl(D);
547   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
548 }
549 
550 void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
551   VisitObjCContainerDecl(D);
552   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
553   Writer.AddSourceLocation(D->getIvarLBraceLoc(), Record);
554   Writer.AddSourceLocation(D->getIvarRBraceLoc(), Record);
555   Writer.AddDeclRef(D->getClassInterface(), Record);
556   Record.push_back(D->protocol_size());
557   for (ObjCCategoryDecl::protocol_iterator
558        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
559     Writer.AddDeclRef(*I, Record);
560   for (ObjCCategoryDecl::protocol_loc_iterator
561          PL = D->protocol_loc_begin(), PLEnd = D->protocol_loc_end();
562        PL != PLEnd; ++PL)
563     Writer.AddSourceLocation(*PL, Record);
564   Code = serialization::DECL_OBJC_CATEGORY;
565 }
566 
567 void ASTDeclWriter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D) {
568   VisitNamedDecl(D);
569   Writer.AddDeclRef(D->getClassInterface(), Record);
570   Code = serialization::DECL_OBJC_COMPATIBLE_ALIAS;
571 }
572 
573 void ASTDeclWriter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
574   VisitNamedDecl(D);
575   Writer.AddSourceLocation(D->getAtLoc(), Record);
576   Writer.AddSourceLocation(D->getLParenLoc(), Record);
577   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
578   // FIXME: stable encoding
579   Record.push_back((unsigned)D->getPropertyAttributes());
580   Record.push_back((unsigned)D->getPropertyAttributesAsWritten());
581   // FIXME: stable encoding
582   Record.push_back((unsigned)D->getPropertyImplementation());
583   Writer.AddDeclarationName(D->getGetterName(), Record);
584   Writer.AddDeclarationName(D->getSetterName(), Record);
585   Writer.AddDeclRef(D->getGetterMethodDecl(), Record);
586   Writer.AddDeclRef(D->getSetterMethodDecl(), Record);
587   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
588   Code = serialization::DECL_OBJC_PROPERTY;
589 }
590 
591 void ASTDeclWriter::VisitObjCImplDecl(ObjCImplDecl *D) {
592   VisitObjCContainerDecl(D);
593   Writer.AddDeclRef(D->getClassInterface(), Record);
594   // Abstract class (no need to define a stable serialization::DECL code).
595 }
596 
597 void ASTDeclWriter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
598   VisitObjCImplDecl(D);
599   Writer.AddIdentifierRef(D->getIdentifier(), Record);
600   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
601   Code = serialization::DECL_OBJC_CATEGORY_IMPL;
602 }
603 
604 void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
605   VisitObjCImplDecl(D);
606   Writer.AddDeclRef(D->getSuperClass(), Record);
607   Writer.AddSourceLocation(D->getIvarLBraceLoc(), Record);
608   Writer.AddSourceLocation(D->getIvarRBraceLoc(), Record);
609   Writer.AddCXXCtorInitializers(D->IvarInitializers, D->NumIvarInitializers,
610                                 Record);
611   Code = serialization::DECL_OBJC_IMPLEMENTATION;
612 }
613 
614 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
615   VisitDecl(D);
616   Writer.AddSourceLocation(D->getLocStart(), Record);
617   Writer.AddDeclRef(D->getPropertyDecl(), Record);
618   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
619   Writer.AddSourceLocation(D->getPropertyIvarDeclLoc(), Record);
620   Writer.AddStmt(D->getGetterCXXConstructor());
621   Writer.AddStmt(D->getSetterCXXAssignment());
622   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
623 }
624 
625 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
626   VisitDeclaratorDecl(D);
627   Record.push_back(D->isMutable());
628   if (D->InitializerOrBitWidth.getInt() != ICIS_NoInit ||
629       D->InitializerOrBitWidth.getPointer()) {
630     Record.push_back(D->InitializerOrBitWidth.getInt() + 1);
631     Writer.AddStmt(D->InitializerOrBitWidth.getPointer());
632   } else {
633     Record.push_back(0);
634   }
635   if (!D->getDeclName())
636     Writer.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D), Record);
637 
638   if (!D->hasAttrs() &&
639       !D->isImplicit() &&
640       !D->isUsed(false) &&
641       !D->isInvalidDecl() &&
642       !D->isReferenced() &&
643       !D->isTopLevelDeclInObjCContainer() &&
644       !D->isModulePrivate() &&
645       !D->getBitWidth() &&
646       !D->hasInClassInitializer() &&
647       !D->hasExtInfo() &&
648       !ObjCIvarDecl::classofKind(D->getKind()) &&
649       !ObjCAtDefsFieldDecl::classofKind(D->getKind()) &&
650       D->getDeclName())
651     AbbrevToUse = Writer.getDeclFieldAbbrev();
652 
653   Code = serialization::DECL_FIELD;
654 }
655 
656 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
657   VisitValueDecl(D);
658   Record.push_back(D->getChainingSize());
659 
660   for (IndirectFieldDecl::chain_iterator
661        P = D->chain_begin(),
662        PEnd = D->chain_end(); P != PEnd; ++P)
663     Writer.AddDeclRef(*P, Record);
664   Code = serialization::DECL_INDIRECTFIELD;
665 }
666 
667 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
668   VisitRedeclarable(D);
669   VisitDeclaratorDecl(D);
670   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
671   Record.push_back(D->getStorageClassAsWritten());
672   Record.push_back(D->isThreadSpecified());
673   Record.push_back(D->getInitStyle());
674   Record.push_back(D->isExceptionVariable());
675   Record.push_back(D->isNRVOVariable());
676   Record.push_back(D->isCXXForRangeDecl());
677   Record.push_back(D->isARCPseudoStrong());
678   if (D->getInit()) {
679     Record.push_back(!D->isInitKnownICE() ? 1 : (D->isInitICE() ? 3 : 2));
680     Writer.AddStmt(D->getInit());
681   } else {
682     Record.push_back(0);
683   }
684 
685   MemberSpecializationInfo *SpecInfo
686     = D->isStaticDataMember() ? D->getMemberSpecializationInfo() : 0;
687   Record.push_back(SpecInfo != 0);
688   if (SpecInfo) {
689     Writer.AddDeclRef(SpecInfo->getInstantiatedFrom(), Record);
690     Record.push_back(SpecInfo->getTemplateSpecializationKind());
691     Writer.AddSourceLocation(SpecInfo->getPointOfInstantiation(), Record);
692   }
693 
694   if (!D->hasAttrs() &&
695       !D->isImplicit() &&
696       !D->isUsed(false) &&
697       !D->isInvalidDecl() &&
698       !D->isReferenced() &&
699       !D->isTopLevelDeclInObjCContainer() &&
700       D->getAccess() == AS_none &&
701       !D->isModulePrivate() &&
702       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
703       !D->hasExtInfo() &&
704       D->getFirstDeclaration() == D->getMostRecentDecl() &&
705       D->getInitStyle() == VarDecl::CInit &&
706       D->getInit() == 0 &&
707       !isa<ParmVarDecl>(D) &&
708       !SpecInfo)
709     AbbrevToUse = Writer.getDeclVarAbbrev();
710 
711   Code = serialization::DECL_VAR;
712 }
713 
714 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
715   VisitVarDecl(D);
716   Code = serialization::DECL_IMPLICIT_PARAM;
717 }
718 
719 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
720   VisitVarDecl(D);
721   Record.push_back(D->isObjCMethodParameter());
722   Record.push_back(D->getFunctionScopeDepth());
723   Record.push_back(D->getFunctionScopeIndex());
724   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
725   Record.push_back(D->isKNRPromoted());
726   Record.push_back(D->hasInheritedDefaultArg());
727   Record.push_back(D->hasUninstantiatedDefaultArg());
728   if (D->hasUninstantiatedDefaultArg())
729     Writer.AddStmt(D->getUninstantiatedDefaultArg());
730   Code = serialization::DECL_PARM_VAR;
731 
732   assert(!D->isARCPseudoStrong()); // can be true of ImplicitParamDecl
733 
734   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
735   // we dynamically check for the properties that we optimize for, but don't
736   // know are true of all PARM_VAR_DECLs.
737   if (!D->hasAttrs() &&
738       !D->hasExtInfo() &&
739       !D->isImplicit() &&
740       !D->isUsed(false) &&
741       !D->isInvalidDecl() &&
742       !D->isReferenced() &&
743       D->getAccess() == AS_none &&
744       !D->isModulePrivate() &&
745       D->getStorageClass() == 0 &&
746       D->getInitStyle() == VarDecl::CInit && // Can params have anything else?
747       D->getFunctionScopeDepth() == 0 &&
748       D->getObjCDeclQualifier() == 0 &&
749       !D->isKNRPromoted() &&
750       !D->hasInheritedDefaultArg() &&
751       D->getInit() == 0 &&
752       !D->hasUninstantiatedDefaultArg())  // No default expr.
753     AbbrevToUse = Writer.getDeclParmVarAbbrev();
754 
755   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
756   // just us assuming it.
757   assert(!D->isThreadSpecified() && "PARM_VAR_DECL can't be __thread");
758   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
759   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
760   assert(D->getPreviousDecl() == 0 && "PARM_VAR_DECL can't be redecl");
761   assert(!D->isStaticDataMember() &&
762          "PARM_VAR_DECL can't be static data member");
763 }
764 
765 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
766   VisitDecl(D);
767   Writer.AddStmt(D->getAsmString());
768   Writer.AddSourceLocation(D->getRParenLoc(), Record);
769   Code = serialization::DECL_FILE_SCOPE_ASM;
770 }
771 
772 void ASTDeclWriter::VisitBlockDecl(BlockDecl *D) {
773   VisitDecl(D);
774   Writer.AddStmt(D->getBody());
775   Writer.AddTypeSourceInfo(D->getSignatureAsWritten(), Record);
776   Record.push_back(D->param_size());
777   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
778        P != PEnd; ++P)
779     Writer.AddDeclRef(*P, Record);
780   Record.push_back(D->isVariadic());
781   Record.push_back(D->blockMissingReturnType());
782   Record.push_back(D->isConversionFromLambda());
783   Record.push_back(D->capturesCXXThis());
784   Record.push_back(D->getNumCaptures());
785   for (BlockDecl::capture_iterator
786          i = D->capture_begin(), e = D->capture_end(); i != e; ++i) {
787     const BlockDecl::Capture &capture = *i;
788     Writer.AddDeclRef(capture.getVariable(), Record);
789 
790     unsigned flags = 0;
791     if (capture.isByRef()) flags |= 1;
792     if (capture.isNested()) flags |= 2;
793     if (capture.hasCopyExpr()) flags |= 4;
794     Record.push_back(flags);
795 
796     if (capture.hasCopyExpr()) Writer.AddStmt(capture.getCopyExpr());
797   }
798 
799   Code = serialization::DECL_BLOCK;
800 }
801 
802 void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
803   VisitDecl(D);
804   Record.push_back(D->getLanguage());
805   Writer.AddSourceLocation(D->getExternLoc(), Record);
806   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
807   Code = serialization::DECL_LINKAGE_SPEC;
808 }
809 
810 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
811   VisitNamedDecl(D);
812   Writer.AddSourceLocation(D->getLocStart(), Record);
813   Code = serialization::DECL_LABEL;
814 }
815 
816 
817 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
818   VisitRedeclarable(D);
819   VisitNamedDecl(D);
820   Record.push_back(D->isInline());
821   Writer.AddSourceLocation(D->getLocStart(), Record);
822   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
823 
824   if (D->isOriginalNamespace())
825     Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
826   Code = serialization::DECL_NAMESPACE;
827 
828   if (Writer.hasChain() && !D->isOriginalNamespace() &&
829       D->getOriginalNamespace()->isFromASTFile()) {
830     NamespaceDecl *NS = D->getOriginalNamespace();
831     Writer.AddUpdatedDeclContext(NS);
832 
833     // Make sure all visible decls are written. They will be recorded later.
834     if (StoredDeclsMap *Map = NS->buildLookup()) {
835       for (StoredDeclsMap::iterator D = Map->begin(), DEnd = Map->end();
836            D != DEnd; ++D) {
837         DeclContext::lookup_result Result = D->second.getLookupResult();
838         while (Result.first != Result.second) {
839           Writer.GetDeclRef(*Result.first);
840           ++Result.first;
841         }
842       }
843     }
844   }
845 
846   if (Writer.hasChain() && D->isAnonymousNamespace() &&
847       D == D->getMostRecentDecl()) {
848     // This is a most recent reopening of the anonymous namespace. If its parent
849     // is in a previous PCH (or is the TU), mark that parent for update, because
850     // the original namespace always points to the latest re-opening of its
851     // anonymous namespace.
852     Decl *Parent = cast<Decl>(
853         D->getParent()->getRedeclContext()->getPrimaryContext());
854     if (Parent->isFromASTFile() || isa<TranslationUnitDecl>(Parent)) {
855       ASTWriter::UpdateRecord &Record = Writer.DeclUpdates[Parent];
856       Record.push_back(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE);
857       Writer.AddDeclRef(D, Record);
858     }
859   }
860 }
861 
862 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
863   VisitNamedDecl(D);
864   Writer.AddSourceLocation(D->getNamespaceLoc(), Record);
865   Writer.AddSourceLocation(D->getTargetNameLoc(), Record);
866   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
867   Writer.AddDeclRef(D->getNamespace(), Record);
868   Code = serialization::DECL_NAMESPACE_ALIAS;
869 }
870 
871 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
872   VisitNamedDecl(D);
873   Writer.AddSourceLocation(D->getUsingLocation(), Record);
874   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
875   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
876   Writer.AddDeclRef(D->FirstUsingShadow.getPointer(), Record);
877   Record.push_back(D->isTypeName());
878   Writer.AddDeclRef(Context.getInstantiatedFromUsingDecl(D), Record);
879   Code = serialization::DECL_USING;
880 }
881 
882 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
883   VisitNamedDecl(D);
884   Writer.AddDeclRef(D->getTargetDecl(), Record);
885   Writer.AddDeclRef(D->UsingOrNextShadow, Record);
886   Writer.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D), Record);
887   Code = serialization::DECL_USING_SHADOW;
888 }
889 
890 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
891   VisitNamedDecl(D);
892   Writer.AddSourceLocation(D->getUsingLoc(), Record);
893   Writer.AddSourceLocation(D->getNamespaceKeyLocation(), Record);
894   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
895   Writer.AddDeclRef(D->getNominatedNamespace(), Record);
896   Writer.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()), Record);
897   Code = serialization::DECL_USING_DIRECTIVE;
898 }
899 
900 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
901   VisitValueDecl(D);
902   Writer.AddSourceLocation(D->getUsingLoc(), Record);
903   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
904   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
905   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
906 }
907 
908 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
909                                                UnresolvedUsingTypenameDecl *D) {
910   VisitTypeDecl(D);
911   Writer.AddSourceLocation(D->getTypenameLoc(), Record);
912   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
913   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
914 }
915 
916 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
917   VisitRecordDecl(D);
918   Record.push_back(D->isThisDeclarationADefinition());
919   if (D->isThisDeclarationADefinition())
920     Writer.AddCXXDefinitionData(D, Record);
921 
922   enum {
923     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
924   };
925   if (ClassTemplateDecl *TemplD = D->getDescribedClassTemplate()) {
926     Record.push_back(CXXRecTemplate);
927     Writer.AddDeclRef(TemplD, Record);
928   } else if (MemberSpecializationInfo *MSInfo
929                = D->getMemberSpecializationInfo()) {
930     Record.push_back(CXXRecMemberSpecialization);
931     Writer.AddDeclRef(MSInfo->getInstantiatedFrom(), Record);
932     Record.push_back(MSInfo->getTemplateSpecializationKind());
933     Writer.AddSourceLocation(MSInfo->getPointOfInstantiation(), Record);
934   } else {
935     Record.push_back(CXXRecNotTemplate);
936   }
937 
938   // Store the key function to avoid deserializing every method so we can
939   // compute it.
940   if (D->IsCompleteDefinition)
941     Writer.AddDeclRef(Context.getKeyFunction(D), Record);
942 
943   Code = serialization::DECL_CXX_RECORD;
944 }
945 
946 void ASTDeclWriter::VisitCXXMethodDecl(CXXMethodDecl *D) {
947   VisitFunctionDecl(D);
948   Record.push_back(D->size_overridden_methods());
949   for (CXXMethodDecl::method_iterator
950          I = D->begin_overridden_methods(), E = D->end_overridden_methods();
951          I != E; ++I)
952     Writer.AddDeclRef(*I, Record);
953   Code = serialization::DECL_CXX_METHOD;
954 }
955 
956 void ASTDeclWriter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
957   VisitCXXMethodDecl(D);
958 
959   Record.push_back(D->IsExplicitSpecified);
960   Record.push_back(D->ImplicitlyDefined);
961   Writer.AddCXXCtorInitializers(D->CtorInitializers, D->NumCtorInitializers,
962                                 Record);
963 
964   Code = serialization::DECL_CXX_CONSTRUCTOR;
965 }
966 
967 void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
968   VisitCXXMethodDecl(D);
969 
970   Record.push_back(D->ImplicitlyDefined);
971   Writer.AddDeclRef(D->OperatorDelete, Record);
972 
973   Code = serialization::DECL_CXX_DESTRUCTOR;
974 }
975 
976 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
977   VisitCXXMethodDecl(D);
978   Record.push_back(D->IsExplicitSpecified);
979   Code = serialization::DECL_CXX_CONVERSION;
980 }
981 
982 void ASTDeclWriter::VisitImportDecl(ImportDecl *D) {
983   VisitDecl(D);
984   ArrayRef<SourceLocation> IdentifierLocs = D->getIdentifierLocs();
985   Record.push_back(!IdentifierLocs.empty());
986   if (IdentifierLocs.empty()) {
987     Writer.AddSourceLocation(D->getLocEnd(), Record);
988     Record.push_back(1);
989   } else {
990     for (unsigned I = 0, N = IdentifierLocs.size(); I != N; ++I)
991       Writer.AddSourceLocation(IdentifierLocs[I], Record);
992     Record.push_back(IdentifierLocs.size());
993   }
994   // Note: the number of source locations must always be the last element in
995   // the record.
996   Code = serialization::DECL_IMPORT;
997 }
998 
999 void ASTDeclWriter::VisitAccessSpecDecl(AccessSpecDecl *D) {
1000   VisitDecl(D);
1001   Writer.AddSourceLocation(D->getColonLoc(), Record);
1002   Code = serialization::DECL_ACCESS_SPEC;
1003 }
1004 
1005 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
1006   VisitDecl(D);
1007   Record.push_back(D->Friend.is<TypeSourceInfo*>());
1008   if (D->Friend.is<TypeSourceInfo*>())
1009     Writer.AddTypeSourceInfo(D->Friend.get<TypeSourceInfo*>(), Record);
1010   else
1011     Writer.AddDeclRef(D->Friend.get<NamedDecl*>(), Record);
1012   Writer.AddDeclRef(D->getNextFriend(), Record);
1013   Record.push_back(D->UnsupportedFriend);
1014   Writer.AddSourceLocation(D->FriendLoc, Record);
1015   Code = serialization::DECL_FRIEND;
1016 }
1017 
1018 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
1019   VisitDecl(D);
1020   Record.push_back(D->getNumTemplateParameters());
1021   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
1022     Writer.AddTemplateParameterList(D->getTemplateParameterList(i), Record);
1023   Record.push_back(D->getFriendDecl() != 0);
1024   if (D->getFriendDecl())
1025     Writer.AddDeclRef(D->getFriendDecl(), Record);
1026   else
1027     Writer.AddTypeSourceInfo(D->getFriendType(), Record);
1028   Writer.AddSourceLocation(D->getFriendLoc(), Record);
1029   Code = serialization::DECL_FRIEND_TEMPLATE;
1030 }
1031 
1032 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
1033   VisitNamedDecl(D);
1034 
1035   Writer.AddDeclRef(D->getTemplatedDecl(), Record);
1036   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1037 }
1038 
1039 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
1040   VisitRedeclarable(D);
1041 
1042   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
1043   // getCommonPtr() can be used while this is still initializing.
1044   if (D->isFirstDeclaration()) {
1045     // This declaration owns the 'common' pointer, so serialize that data now.
1046     Writer.AddDeclRef(D->getInstantiatedFromMemberTemplate(), Record);
1047     if (D->getInstantiatedFromMemberTemplate())
1048       Record.push_back(D->isMemberSpecialization());
1049   }
1050 
1051   VisitTemplateDecl(D);
1052   Record.push_back(D->getIdentifierNamespace());
1053 }
1054 
1055 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1056   VisitRedeclarableTemplateDecl(D);
1057 
1058   if (D->isFirstDeclaration()) {
1059     typedef llvm::FoldingSetVector<ClassTemplateSpecializationDecl> CTSDSetTy;
1060     CTSDSetTy &CTSDSet = D->getSpecializations();
1061     Record.push_back(CTSDSet.size());
1062     for (CTSDSetTy::iterator I=CTSDSet.begin(), E = CTSDSet.end(); I!=E; ++I) {
1063       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1064       Writer.AddDeclRef(&*I, Record);
1065     }
1066 
1067     typedef llvm::FoldingSetVector<ClassTemplatePartialSpecializationDecl>
1068       CTPSDSetTy;
1069     CTPSDSetTy &CTPSDSet = D->getPartialSpecializations();
1070     Record.push_back(CTPSDSet.size());
1071     for (CTPSDSetTy::iterator I=CTPSDSet.begin(), E=CTPSDSet.end(); I!=E; ++I) {
1072       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1073       Writer.AddDeclRef(&*I, Record);
1074     }
1075 
1076     // InjectedClassNameType is computed, no need to write it.
1077   }
1078   Code = serialization::DECL_CLASS_TEMPLATE;
1079 }
1080 
1081 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
1082                                            ClassTemplateSpecializationDecl *D) {
1083   VisitCXXRecordDecl(D);
1084 
1085   llvm::PointerUnion<ClassTemplateDecl *,
1086                      ClassTemplatePartialSpecializationDecl *> InstFrom
1087     = D->getSpecializedTemplateOrPartial();
1088   if (Decl *InstFromD = InstFrom.dyn_cast<ClassTemplateDecl *>()) {
1089     Writer.AddDeclRef(InstFromD, Record);
1090   } else {
1091     Writer.AddDeclRef(InstFrom.get<ClassTemplatePartialSpecializationDecl *>(),
1092                       Record);
1093     Writer.AddTemplateArgumentList(&D->getTemplateInstantiationArgs(), Record);
1094   }
1095 
1096   // Explicit info.
1097   Writer.AddTypeSourceInfo(D->getTypeAsWritten(), Record);
1098   if (D->getTypeAsWritten()) {
1099     Writer.AddSourceLocation(D->getExternLoc(), Record);
1100     Writer.AddSourceLocation(D->getTemplateKeywordLoc(), Record);
1101   }
1102 
1103   Writer.AddTemplateArgumentList(&D->getTemplateArgs(), Record);
1104   Writer.AddSourceLocation(D->getPointOfInstantiation(), Record);
1105   Record.push_back(D->getSpecializationKind());
1106 
1107   if (D->isCanonicalDecl()) {
1108     // When reading, we'll add it to the folding set of the following template.
1109     Writer.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl(), Record);
1110   }
1111 
1112   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
1113 }
1114 
1115 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
1116                                     ClassTemplatePartialSpecializationDecl *D) {
1117   VisitClassTemplateSpecializationDecl(D);
1118 
1119   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1120 
1121   Record.push_back(D->getNumTemplateArgsAsWritten());
1122   for (int i = 0, e = D->getNumTemplateArgsAsWritten(); i != e; ++i)
1123     Writer.AddTemplateArgumentLoc(D->getTemplateArgsAsWritten()[i], Record);
1124 
1125   Record.push_back(D->getSequenceNumber());
1126 
1127   // These are read/set from/to the first declaration.
1128   if (D->getPreviousDecl() == 0) {
1129     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
1130     Record.push_back(D->isMemberSpecialization());
1131   }
1132 
1133   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
1134 }
1135 
1136 void ASTDeclWriter::VisitClassScopeFunctionSpecializationDecl(
1137                                     ClassScopeFunctionSpecializationDecl *D) {
1138   VisitDecl(D);
1139   Writer.AddDeclRef(D->getSpecialization(), Record);
1140   Code = serialization::DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION;
1141 }
1142 
1143 
1144 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1145   VisitRedeclarableTemplateDecl(D);
1146 
1147   if (D->isFirstDeclaration()) {
1148     // This FunctionTemplateDecl owns the CommonPtr; write it.
1149 
1150     // Write the function specialization declarations.
1151     Record.push_back(D->getSpecializations().size());
1152     for (llvm::FoldingSetVector<FunctionTemplateSpecializationInfo>::iterator
1153            I = D->getSpecializations().begin(),
1154            E = D->getSpecializations().end()   ; I != E; ++I) {
1155       assert(I->Function->isCanonicalDecl() &&
1156              "Expected only canonical decls in set");
1157       Writer.AddDeclRef(I->Function, Record);
1158     }
1159   }
1160   Code = serialization::DECL_FUNCTION_TEMPLATE;
1161 }
1162 
1163 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1164   VisitTypeDecl(D);
1165 
1166   Record.push_back(D->wasDeclaredWithTypename());
1167   Record.push_back(D->defaultArgumentWasInherited());
1168   Writer.AddTypeSourceInfo(D->getDefaultArgumentInfo(), Record);
1169 
1170   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1171 }
1172 
1173 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1174   // For an expanded parameter pack, record the number of expansion types here
1175   // so that it's easier for
1176   if (D->isExpandedParameterPack())
1177     Record.push_back(D->getNumExpansionTypes());
1178 
1179   VisitDeclaratorDecl(D);
1180   // TemplateParmPosition.
1181   Record.push_back(D->getDepth());
1182   Record.push_back(D->getPosition());
1183 
1184   if (D->isExpandedParameterPack()) {
1185     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1186       Writer.AddTypeRef(D->getExpansionType(I), Record);
1187       Writer.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I), Record);
1188     }
1189 
1190     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1191   } else {
1192     // Rest of NonTypeTemplateParmDecl.
1193     Record.push_back(D->isParameterPack());
1194     Record.push_back(D->getDefaultArgument() != 0);
1195     if (D->getDefaultArgument()) {
1196       Writer.AddStmt(D->getDefaultArgument());
1197       Record.push_back(D->defaultArgumentWasInherited());
1198     }
1199     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1200   }
1201 }
1202 
1203 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1204   VisitTemplateDecl(D);
1205   // TemplateParmPosition.
1206   Record.push_back(D->getDepth());
1207   Record.push_back(D->getPosition());
1208   // Rest of TemplateTemplateParmDecl.
1209   Writer.AddTemplateArgumentLoc(D->getDefaultArgument(), Record);
1210   Record.push_back(D->defaultArgumentWasInherited());
1211   Record.push_back(D->isParameterPack());
1212   Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1213 }
1214 
1215 void ASTDeclWriter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
1216   VisitRedeclarableTemplateDecl(D);
1217   Code = serialization::DECL_TYPE_ALIAS_TEMPLATE;
1218 }
1219 
1220 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1221   VisitDecl(D);
1222   Writer.AddStmt(D->getAssertExpr());
1223   Record.push_back(D->isFailed());
1224   Writer.AddStmt(D->getMessage());
1225   Writer.AddSourceLocation(D->getRParenLoc(), Record);
1226   Code = serialization::DECL_STATIC_ASSERT;
1227 }
1228 
1229 /// \brief Emit the DeclContext part of a declaration context decl.
1230 ///
1231 /// \param LexicalOffset the offset at which the DECL_CONTEXT_LEXICAL
1232 /// block for this declaration context is stored. May be 0 to indicate
1233 /// that there are no declarations stored within this context.
1234 ///
1235 /// \param VisibleOffset the offset at which the DECL_CONTEXT_VISIBLE
1236 /// block for this declaration context is stored. May be 0 to indicate
1237 /// that there are no declarations visible from this context. Note
1238 /// that this value will not be emitted for non-primary declaration
1239 /// contexts.
1240 void ASTDeclWriter::VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
1241                                      uint64_t VisibleOffset) {
1242   Record.push_back(LexicalOffset);
1243   Record.push_back(VisibleOffset);
1244 }
1245 
1246 template <typename T>
1247 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1248   T *First = D->getFirstDeclaration();
1249   if (First->getMostRecentDecl() != First) {
1250     // There is more than one declaration of this entity, so we will need to
1251     // write a redeclaration chain.
1252     Writer.AddDeclRef(First, Record);
1253     Writer.Redeclarations.insert(First);
1254 
1255     // Make sure that we serialize both the previous and the most-recent
1256     // declarations, which (transitively) ensures that all declarations in the
1257     // chain get serialized.
1258     (void)Writer.GetDeclRef(D->getPreviousDecl());
1259     (void)Writer.GetDeclRef(First->getMostRecentDecl());
1260   } else {
1261     // We use the sentinel value 0 to indicate an only declaration.
1262     Record.push_back(0);
1263   }
1264 
1265 }
1266 
1267 //===----------------------------------------------------------------------===//
1268 // ASTWriter Implementation
1269 //===----------------------------------------------------------------------===//
1270 
1271 void ASTWriter::WriteDeclsBlockAbbrevs() {
1272   using namespace llvm;
1273 
1274   BitCodeAbbrev *Abv;
1275 
1276   // Abbreviation for DECL_FIELD
1277   Abv = new BitCodeAbbrev();
1278   Abv->Add(BitCodeAbbrevOp(serialization::DECL_FIELD));
1279   // Decl
1280   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1281   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1282   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1283   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1284   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1285   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1286   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1287   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1288   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1289   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1290   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1291   // NamedDecl
1292   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1293   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1294   // ValueDecl
1295   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1296   // DeclaratorDecl
1297   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1298   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1299   // FieldDecl
1300   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1301   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1302   // Type Source Info
1303   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1304   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1305   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1306   DeclFieldAbbrev = Stream.EmitAbbrev(Abv);
1307 
1308   // Abbreviation for DECL_OBJC_IVAR
1309   Abv = new BitCodeAbbrev();
1310   Abv->Add(BitCodeAbbrevOp(serialization::DECL_OBJC_IVAR));
1311   // Decl
1312   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1313   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1314   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1315   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1316   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1317   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1318   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1319   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1320   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1321   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1322   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1323   // NamedDecl
1324   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1325   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1326   // ValueDecl
1327   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1328   // DeclaratorDecl
1329   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1330   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1331   // FieldDecl
1332   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1333   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1334   // ObjC Ivar
1335   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getAccessControl
1336   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getSynthesize
1337   // Type Source Info
1338   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1339   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1340   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1341   DeclObjCIvarAbbrev = Stream.EmitAbbrev(Abv);
1342 
1343   // Abbreviation for DECL_ENUM
1344   Abv = new BitCodeAbbrev();
1345   Abv->Add(BitCodeAbbrevOp(serialization::DECL_ENUM));
1346   // Redeclarable
1347   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1348   // Decl
1349   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1350   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1351   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1352   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1353   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1354   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1355   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1356   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1357   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1358   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1359   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1360   // NamedDecl
1361   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1362   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1363   // TypeDecl
1364   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1365   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1366   // TagDecl
1367   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1368   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1369   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1370   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1371   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1372   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1373   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1374   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1375   // EnumDecl
1376   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddTypeRef
1377   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IntegerType
1378   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getPromotionType
1379   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumPositiveBits
1380   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumNegativeBits
1381   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScoped
1382   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScopedUsingClassTag
1383   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isFixed
1384   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InstantiatedMembEnum
1385   // DC
1386   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1387   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1388   DeclEnumAbbrev = Stream.EmitAbbrev(Abv);
1389 
1390   // Abbreviation for DECL_RECORD
1391   Abv = new BitCodeAbbrev();
1392   Abv->Add(BitCodeAbbrevOp(serialization::DECL_RECORD));
1393   // Redeclarable
1394   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1395   // Decl
1396   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1397   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1398   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1399   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1400   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1401   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1402   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1403   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1404   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1405   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1406   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1407   // NamedDecl
1408   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1409   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1410   // TypeDecl
1411   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1412   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1413   // TagDecl
1414   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1415   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1416   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1417   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1418   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1419   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1420   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1421   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1422   // RecordDecl
1423   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // FlexibleArrayMember
1424   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // AnonymousStructUnion
1425   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasObjectMember
1426   // DC
1427   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1428   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1429   DeclRecordAbbrev = Stream.EmitAbbrev(Abv);
1430 
1431   // Abbreviation for DECL_PARM_VAR
1432   Abv = new BitCodeAbbrev();
1433   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1434   // Redeclarable
1435   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1436   // Decl
1437   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1438   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1439   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1440   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1441   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1442   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1443   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1444   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1445   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1446   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1447   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1448   // NamedDecl
1449   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1450   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1451   // ValueDecl
1452   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1453   // DeclaratorDecl
1454   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1455   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1456   // VarDecl
1457   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClass
1458   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClassAsWritten
1459   Abv->Add(BitCodeAbbrevOp(0));                       // isThreadSpecified
1460   Abv->Add(BitCodeAbbrevOp(0));                       // hasCXXDirectInitializer
1461   Abv->Add(BitCodeAbbrevOp(0));                       // isExceptionVariable
1462   Abv->Add(BitCodeAbbrevOp(0));                       // isNRVOVariable
1463   Abv->Add(BitCodeAbbrevOp(0));                       // isCXXForRangeDecl
1464   Abv->Add(BitCodeAbbrevOp(0));                       // isARCPseudoStrong
1465   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
1466   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
1467   // ParmVarDecl
1468   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsObjCMethodParameter
1469   Abv->Add(BitCodeAbbrevOp(0));                       // ScopeDepth
1470   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ScopeIndex
1471   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
1472   Abv->Add(BitCodeAbbrevOp(0));                       // KNRPromoted
1473   Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
1474   Abv->Add(BitCodeAbbrevOp(0));                   // HasUninstantiatedDefaultArg
1475   // Type Source Info
1476   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1477   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1478   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1479   DeclParmVarAbbrev = Stream.EmitAbbrev(Abv);
1480 
1481   // Abbreviation for DECL_TYPEDEF
1482   Abv = new BitCodeAbbrev();
1483   Abv->Add(BitCodeAbbrevOp(serialization::DECL_TYPEDEF));
1484   // Redeclarable
1485   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1486   // Decl
1487   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1488   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1489   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1490   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1491   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1492   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1493   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1494   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1495   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1496   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1497   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1498   // NamedDecl
1499   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1500   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1501   // TypeDecl
1502   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1503   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1504   // TypedefDecl
1505   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1506   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1507   DeclTypedefAbbrev = Stream.EmitAbbrev(Abv);
1508 
1509   // Abbreviation for DECL_VAR
1510   Abv = new BitCodeAbbrev();
1511   Abv->Add(BitCodeAbbrevOp(serialization::DECL_VAR));
1512   // Redeclarable
1513   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1514   // Decl
1515   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1516   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1517   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1518   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1519   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1520   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1521   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1522   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1523   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1524   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1525   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1526   // NamedDecl
1527   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1528   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1529   // ValueDecl
1530   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1531   // DeclaratorDecl
1532   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1533   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1534   // VarDecl
1535   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClass
1536   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClassAsWritten
1537   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isThreadSpecified
1538   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // CXXDirectInitializer
1539   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
1540   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
1541   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
1542   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
1543   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasInit
1544   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasMemberSpecInfo
1545   // Type Source Info
1546   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1547   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1548   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1549   DeclVarAbbrev = Stream.EmitAbbrev(Abv);
1550 
1551   // Abbreviation for EXPR_DECL_REF
1552   Abv = new BitCodeAbbrev();
1553   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_DECL_REF));
1554   //Stmt
1555   //Expr
1556   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1557   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1558   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1559   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1560   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1561   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1562   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1563   //DeclRefExpr
1564   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HasQualifier
1565   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //GetDeclFound
1566   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ExplicitTemplateArgs
1567   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HadMultipleCandidates
1568   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //RefersToEnclosingLocal
1569   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclRef
1570   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1571   DeclRefExprAbbrev = Stream.EmitAbbrev(Abv);
1572 
1573   // Abbreviation for EXPR_INTEGER_LITERAL
1574   Abv = new BitCodeAbbrev();
1575   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_INTEGER_LITERAL));
1576   //Stmt
1577   //Expr
1578   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1579   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1580   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1581   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1582   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1583   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1584   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1585   //Integer Literal
1586   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1587   Abv->Add(BitCodeAbbrevOp(32));                      // Bit Width
1588   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Value
1589   IntegerLiteralAbbrev = Stream.EmitAbbrev(Abv);
1590 
1591   // Abbreviation for EXPR_CHARACTER_LITERAL
1592   Abv = new BitCodeAbbrev();
1593   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_CHARACTER_LITERAL));
1594   //Stmt
1595   //Expr
1596   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1597   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1598   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1599   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1600   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1601   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1602   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1603   //Character Literal
1604   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getValue
1605   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1606   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //IsWide
1607   CharacterLiteralAbbrev = Stream.EmitAbbrev(Abv);
1608 
1609   Abv = new BitCodeAbbrev();
1610   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
1611   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1612   DeclContextLexicalAbbrev = Stream.EmitAbbrev(Abv);
1613 
1614   Abv = new BitCodeAbbrev();
1615   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
1616   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1617   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1618   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(Abv);
1619 }
1620 
1621 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
1622 /// consumers of the AST.
1623 ///
1624 /// Such decls will always be deserialized from the AST file, so we would like
1625 /// this to be as restrictive as possible. Currently the predicate is driven by
1626 /// code generation requirements, if other clients have a different notion of
1627 /// what is "required" then we may have to consider an alternate scheme where
1628 /// clients can iterate over the top-level decls and get information on them,
1629 /// without necessary deserializing them. We could explicitly require such
1630 /// clients to use a separate API call to "realize" the decl. This should be
1631 /// relatively painless since they would presumably only do it for top-level
1632 /// decls.
1633 static bool isRequiredDecl(const Decl *D, ASTContext &Context) {
1634   // An ObjCMethodDecl is never considered as "required" because its
1635   // implementation container always is.
1636 
1637   // File scoped assembly or obj-c implementation must be seen.
1638   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplDecl>(D))
1639     return true;
1640 
1641   return Context.DeclMustBeEmitted(D);
1642 }
1643 
1644 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
1645   // Switch case IDs are per Decl.
1646   ClearSwitchCaseIDs();
1647 
1648   RecordData Record;
1649   ASTDeclWriter W(*this, Context, Record);
1650 
1651   // Determine the ID for this declaration.
1652   serialization::DeclID ID;
1653   if (D->isFromASTFile())
1654     ID = getDeclID(D);
1655   else {
1656     serialization::DeclID &IDR = DeclIDs[D];
1657     if (IDR == 0)
1658       IDR = NextDeclID++;
1659 
1660     ID= IDR;
1661   }
1662 
1663   bool isReplacingADecl = ID < FirstDeclID;
1664 
1665   // If this declaration is also a DeclContext, write blocks for the
1666   // declarations that lexically stored inside its context and those
1667   // declarations that are visible from its context. These blocks
1668   // are written before the declaration itself so that we can put
1669   // their offsets into the record for the declaration.
1670   uint64_t LexicalOffset = 0;
1671   uint64_t VisibleOffset = 0;
1672   DeclContext *DC = dyn_cast<DeclContext>(D);
1673   if (DC) {
1674     if (isReplacingADecl) {
1675       // It is replacing a decl from a chained PCH; make sure that the
1676       // DeclContext is fully loaded.
1677       if (DC->hasExternalLexicalStorage())
1678         DC->LoadLexicalDeclsFromExternalStorage();
1679       if (DC->hasExternalVisibleStorage())
1680         Chain->completeVisibleDeclsMap(DC);
1681     }
1682     LexicalOffset = WriteDeclContextLexicalBlock(Context, DC);
1683     VisibleOffset = WriteDeclContextVisibleBlock(Context, DC);
1684   }
1685 
1686   if (isReplacingADecl) {
1687     // We're replacing a decl in a previous file.
1688     ReplacedDecls.push_back(ReplacedDeclInfo(ID, Stream.GetCurrentBitNo(),
1689                                              D->getLocation()));
1690   } else {
1691     unsigned Index = ID - FirstDeclID;
1692 
1693     // Record the offset for this declaration
1694     SourceLocation Loc = D->getLocation();
1695     if (DeclOffsets.size() == Index)
1696       DeclOffsets.push_back(DeclOffset(Loc, Stream.GetCurrentBitNo()));
1697     else if (DeclOffsets.size() < Index) {
1698       DeclOffsets.resize(Index+1);
1699       DeclOffsets[Index].setLocation(Loc);
1700       DeclOffsets[Index].BitOffset = Stream.GetCurrentBitNo();
1701     }
1702 
1703     SourceManager &SM = Context.getSourceManager();
1704     if (Loc.isValid() && SM.isLocalSourceLocation(Loc))
1705       associateDeclWithFile(D, ID);
1706   }
1707 
1708   // Build and emit a record for this declaration
1709   Record.clear();
1710   W.Code = (serialization::DeclCode)0;
1711   W.AbbrevToUse = 0;
1712   W.Visit(D);
1713   if (DC) W.VisitDeclContext(DC, LexicalOffset, VisibleOffset);
1714 
1715   if (!W.Code)
1716     llvm::report_fatal_error(StringRef("unexpected declaration kind '") +
1717                             D->getDeclKindName() + "'");
1718   Stream.EmitRecord(W.Code, Record, W.AbbrevToUse);
1719 
1720   // Flush any expressions that were written as part of this declaration.
1721   FlushStmts();
1722 
1723   // Flush C++ base specifiers, if there are any.
1724   FlushCXXBaseSpecifiers();
1725 
1726   // Note "external" declarations so that we can add them to a record in the
1727   // AST file later.
1728   //
1729   // FIXME: This should be renamed, the predicate is much more complicated.
1730   if (isRequiredDecl(D, Context))
1731     ExternalDefinitions.push_back(ID);
1732 }
1733