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