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