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