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   Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
476   Writer.AddSourceLocation(D->getLocEnd(), Record);
477   Code = serialization::DECL_OBJC_INTERFACE;
478 }
479 
480 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
481   VisitFieldDecl(D);
482   // FIXME: stable encoding for @public/@private/@protected/@package
483   Record.push_back(D->getAccessControl());
484   Record.push_back(D->getSynthesize());
485 
486   if (!D->hasAttrs() &&
487       !D->isImplicit() &&
488       !D->isUsed(false) &&
489       !D->isInvalidDecl() &&
490       !D->isReferenced() &&
491       !D->isModulePrivate() &&
492       !D->getBitWidth() &&
493       !D->hasExtInfo() &&
494       D->getDeclName())
495     AbbrevToUse = Writer.getDeclObjCIvarAbbrev();
496 
497   Code = serialization::DECL_OBJC_IVAR;
498 }
499 
500 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
501   VisitObjCContainerDecl(D);
502   Record.push_back(D->isInitiallyForwardDecl());
503   Record.push_back(D->isForwardDecl());
504   Writer.AddSourceLocation(D->getLocEnd(), Record);
505   Record.push_back(D->protocol_size());
506   for (ObjCProtocolDecl::protocol_iterator
507        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
508     Writer.AddDeclRef(*I, Record);
509   for (ObjCProtocolDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
510          PLEnd = D->protocol_loc_end();
511        PL != PLEnd; ++PL)
512     Writer.AddSourceLocation(*PL, Record);
513   Code = serialization::DECL_OBJC_PROTOCOL;
514 }
515 
516 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
517   VisitFieldDecl(D);
518   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
519 }
520 
521 void ASTDeclWriter::VisitObjCClassDecl(ObjCClassDecl *D) {
522   VisitDecl(D);
523   Writer.AddDeclRef(D->getForwardInterfaceDecl(), Record);
524   Writer.AddSourceLocation(D->getForwardDecl()->getLocation(), Record);
525   Code = serialization::DECL_OBJC_CLASS;
526 }
527 
528 void ASTDeclWriter::VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *D) {
529   VisitDecl(D);
530   Record.push_back(D->protocol_size());
531   for (ObjCForwardProtocolDecl::protocol_iterator
532        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
533     Writer.AddDeclRef(*I, Record);
534   for (ObjCForwardProtocolDecl::protocol_loc_iterator
535          PL = D->protocol_loc_begin(), PLEnd = D->protocol_loc_end();
536        PL != PLEnd; ++PL)
537     Writer.AddSourceLocation(*PL, Record);
538   Code = serialization::DECL_OBJC_FORWARD_PROTOCOL;
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   Code = serialization::DECL_OBJC_CATEGORY_IMPL;
591 }
592 
593 void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
594   VisitObjCImplDecl(D);
595   Writer.AddDeclRef(D->getSuperClass(), Record);
596   Writer.AddCXXCtorInitializers(D->IvarInitializers, D->NumIvarInitializers,
597                                 Record);
598   Record.push_back(D->hasSynthBitfield());
599   Code = serialization::DECL_OBJC_IMPLEMENTATION;
600 }
601 
602 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
603   VisitDecl(D);
604   Writer.AddSourceLocation(D->getLocStart(), Record);
605   Writer.AddDeclRef(D->getPropertyDecl(), Record);
606   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
607   Writer.AddSourceLocation(D->getPropertyIvarDeclLoc(), Record);
608   Writer.AddStmt(D->getGetterCXXConstructor());
609   Writer.AddStmt(D->getSetterCXXAssignment());
610   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
611 }
612 
613 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
614   VisitDeclaratorDecl(D);
615   Record.push_back(D->isMutable());
616   Record.push_back(D->getBitWidth()? 1 : D->hasInClassInitializer() ? 2 : 0);
617   if (D->getBitWidth())
618     Writer.AddStmt(D->getBitWidth());
619   else if (D->hasInClassInitializer())
620     Writer.AddStmt(D->getInClassInitializer());
621   if (!D->getDeclName())
622     Writer.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D), Record);
623 
624   if (!D->hasAttrs() &&
625       !D->isImplicit() &&
626       !D->isUsed(false) &&
627       !D->isInvalidDecl() &&
628       !D->isReferenced() &&
629       !D->isModulePrivate() &&
630       !D->getBitWidth() &&
631       !D->hasInClassInitializer() &&
632       !D->hasExtInfo() &&
633       !ObjCIvarDecl::classofKind(D->getKind()) &&
634       !ObjCAtDefsFieldDecl::classofKind(D->getKind()) &&
635       D->getDeclName())
636     AbbrevToUse = Writer.getDeclFieldAbbrev();
637 
638   Code = serialization::DECL_FIELD;
639 }
640 
641 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
642   VisitValueDecl(D);
643   Record.push_back(D->getChainingSize());
644 
645   for (IndirectFieldDecl::chain_iterator
646        P = D->chain_begin(),
647        PEnd = D->chain_end(); P != PEnd; ++P)
648     Writer.AddDeclRef(*P, Record);
649   Code = serialization::DECL_INDIRECTFIELD;
650 }
651 
652 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
653   VisitRedeclarable(D);
654   VisitDeclaratorDecl(D);
655   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
656   Record.push_back(D->getStorageClassAsWritten());
657   Record.push_back(D->isThreadSpecified());
658   Record.push_back(D->hasCXXDirectInitializer());
659   Record.push_back(D->isExceptionVariable());
660   Record.push_back(D->isNRVOVariable());
661   Record.push_back(D->isCXXForRangeDecl());
662   Record.push_back(D->isARCPseudoStrong());
663   Record.push_back(D->getInit() ? 1 : 0);
664   if (D->getInit())
665     Writer.AddStmt(D->getInit());
666 
667   MemberSpecializationInfo *SpecInfo
668     = D->isStaticDataMember() ? D->getMemberSpecializationInfo() : 0;
669   Record.push_back(SpecInfo != 0);
670   if (SpecInfo) {
671     Writer.AddDeclRef(SpecInfo->getInstantiatedFrom(), Record);
672     Record.push_back(SpecInfo->getTemplateSpecializationKind());
673     Writer.AddSourceLocation(SpecInfo->getPointOfInstantiation(), Record);
674   }
675 
676   if (!D->hasAttrs() &&
677       !D->isImplicit() &&
678       !D->isUsed(false) &&
679       !D->isInvalidDecl() &&
680       !D->isReferenced() &&
681       D->getAccess() == AS_none &&
682       !D->isModulePrivate() &&
683       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
684       !D->hasExtInfo() &&
685       D->RedeclLink.getNext() == D &&
686       !D->hasCXXDirectInitializer() &&
687       D->getInit() == 0 &&
688       !isa<ParmVarDecl>(D) &&
689       !SpecInfo)
690     AbbrevToUse = Writer.getDeclVarAbbrev();
691 
692   Code = serialization::DECL_VAR;
693 }
694 
695 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
696   VisitVarDecl(D);
697   Code = serialization::DECL_IMPLICIT_PARAM;
698 }
699 
700 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
701   VisitVarDecl(D);
702   Record.push_back(D->isObjCMethodParameter());
703   Record.push_back(D->getFunctionScopeDepth());
704   Record.push_back(D->getFunctionScopeIndex());
705   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
706   Record.push_back(D->isKNRPromoted());
707   Record.push_back(D->hasInheritedDefaultArg());
708   Record.push_back(D->hasUninstantiatedDefaultArg());
709   if (D->hasUninstantiatedDefaultArg())
710     Writer.AddStmt(D->getUninstantiatedDefaultArg());
711   Code = serialization::DECL_PARM_VAR;
712 
713   assert(!D->isARCPseudoStrong()); // can be true of ImplicitParamDecl
714 
715   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
716   // we dynamically check for the properties that we optimize for, but don't
717   // know are true of all PARM_VAR_DECLs.
718   if (!D->hasAttrs() &&
719       !D->hasExtInfo() &&
720       !D->isImplicit() &&
721       !D->isUsed(false) &&
722       D->getAccess() == AS_none &&
723       !D->isModulePrivate() &&
724       D->getStorageClass() == 0 &&
725       !D->hasCXXDirectInitializer() && // Can params have this ever?
726       D->getFunctionScopeDepth() == 0 &&
727       D->getObjCDeclQualifier() == 0 &&
728       !D->isKNRPromoted() &&
729       !D->hasInheritedDefaultArg() &&
730       D->getInit() == 0 &&
731       !D->hasUninstantiatedDefaultArg())  // No default expr.
732     AbbrevToUse = Writer.getDeclParmVarAbbrev();
733 
734   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
735   // just us assuming it.
736   assert(!D->isInvalidDecl() && "Shouldn't emit invalid decls");
737   assert(!D->isThreadSpecified() && "PARM_VAR_DECL can't be __thread");
738   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
739   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
740   assert(D->getPreviousDeclaration() == 0 && "PARM_VAR_DECL can't be redecl");
741   assert(!D->isStaticDataMember() &&
742          "PARM_VAR_DECL can't be static data member");
743 }
744 
745 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
746   VisitDecl(D);
747   Writer.AddStmt(D->getAsmString());
748   Writer.AddSourceLocation(D->getRParenLoc(), Record);
749   Code = serialization::DECL_FILE_SCOPE_ASM;
750 }
751 
752 void ASTDeclWriter::VisitBlockDecl(BlockDecl *D) {
753   VisitDecl(D);
754   Writer.AddStmt(D->getBody());
755   Writer.AddTypeSourceInfo(D->getSignatureAsWritten(), Record);
756   Record.push_back(D->param_size());
757   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
758        P != PEnd; ++P)
759     Writer.AddDeclRef(*P, Record);
760   Record.push_back(D->capturesCXXThis());
761   Record.push_back(D->getNumCaptures());
762   for (BlockDecl::capture_iterator
763          i = D->capture_begin(), e = D->capture_end(); i != e; ++i) {
764     const BlockDecl::Capture &capture = *i;
765     Writer.AddDeclRef(capture.getVariable(), Record);
766 
767     unsigned flags = 0;
768     if (capture.isByRef()) flags |= 1;
769     if (capture.isNested()) flags |= 2;
770     if (capture.hasCopyExpr()) flags |= 4;
771     Record.push_back(flags);
772 
773     if (capture.hasCopyExpr()) Writer.AddStmt(capture.getCopyExpr());
774   }
775 
776   Code = serialization::DECL_BLOCK;
777 }
778 
779 void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
780   VisitDecl(D);
781   Record.push_back(D->getLanguage());
782   Writer.AddSourceLocation(D->getExternLoc(), Record);
783   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
784   Code = serialization::DECL_LINKAGE_SPEC;
785 }
786 
787 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
788   VisitNamedDecl(D);
789   Writer.AddSourceLocation(D->getLocStart(), Record);
790   Code = serialization::DECL_LABEL;
791 }
792 
793 
794 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
795   VisitNamedDecl(D);
796   Record.push_back(D->isInline());
797   Writer.AddSourceLocation(D->getLocStart(), Record);
798   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
799   Writer.AddDeclRef(D->getNextNamespace(), Record);
800 
801   // Only write one reference--original or anonymous
802   Record.push_back(D->isOriginalNamespace());
803   if (D->isOriginalNamespace())
804     Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
805   else
806     Writer.AddDeclRef(D->getOriginalNamespace(), Record);
807   Code = serialization::DECL_NAMESPACE;
808 
809   if (Writer.hasChain() && !D->isOriginalNamespace() &&
810       D->getOriginalNamespace()->isFromASTFile()) {
811     NamespaceDecl *NS = D->getOriginalNamespace();
812     Writer.AddUpdatedDeclContext(NS);
813 
814     // Make sure all visible decls are written. They will be recorded later.
815     NS->lookup(DeclarationName());
816     StoredDeclsMap *Map = static_cast<StoredDeclsMap*>(NS->getLookupPtr());
817     if (Map) {
818       for (StoredDeclsMap::iterator D = Map->begin(), DEnd = Map->end();
819            D != DEnd; ++D) {
820         DeclContext::lookup_result Result = D->second.getLookupResult();
821         while (Result.first != Result.second) {
822           Writer.GetDeclRef(*Result.first);
823           ++Result.first;
824         }
825       }
826     }
827   }
828 
829   if (Writer.hasChain() && D->isAnonymousNamespace() && !D->getNextNamespace()){
830     // This is a most recent reopening of the anonymous namespace. If its parent
831     // is in a previous PCH (or is the TU), mark that parent for update, because
832     // the original namespace always points to the latest re-opening of its
833     // anonymous namespace.
834     Decl *Parent = cast<Decl>(
835         D->getParent()->getRedeclContext()->getPrimaryContext());
836     if (Parent->isFromASTFile() || isa<TranslationUnitDecl>(Parent)) {
837       ASTWriter::UpdateRecord &Record = Writer.DeclUpdates[Parent];
838       Record.push_back(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE);
839       Writer.AddDeclRef(D, Record);
840     }
841   }
842 }
843 
844 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
845   VisitNamedDecl(D);
846   Writer.AddSourceLocation(D->getNamespaceLoc(), Record);
847   Writer.AddSourceLocation(D->getTargetNameLoc(), Record);
848   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
849   Writer.AddDeclRef(D->getNamespace(), Record);
850   Code = serialization::DECL_NAMESPACE_ALIAS;
851 }
852 
853 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
854   VisitNamedDecl(D);
855   Writer.AddSourceLocation(D->getUsingLocation(), Record);
856   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
857   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
858   Writer.AddDeclRef(D->FirstUsingShadow, Record);
859   Record.push_back(D->isTypeName());
860   Writer.AddDeclRef(Context.getInstantiatedFromUsingDecl(D), Record);
861   Code = serialization::DECL_USING;
862 }
863 
864 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
865   VisitNamedDecl(D);
866   Writer.AddDeclRef(D->getTargetDecl(), Record);
867   Writer.AddDeclRef(D->UsingOrNextShadow, Record);
868   Writer.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D), Record);
869   Code = serialization::DECL_USING_SHADOW;
870 }
871 
872 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
873   VisitNamedDecl(D);
874   Writer.AddSourceLocation(D->getUsingLoc(), Record);
875   Writer.AddSourceLocation(D->getNamespaceKeyLocation(), Record);
876   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
877   Writer.AddDeclRef(D->getNominatedNamespace(), Record);
878   Writer.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()), Record);
879   Code = serialization::DECL_USING_DIRECTIVE;
880 }
881 
882 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
883   VisitValueDecl(D);
884   Writer.AddSourceLocation(D->getUsingLoc(), Record);
885   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
886   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
887   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
888 }
889 
890 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
891                                                UnresolvedUsingTypenameDecl *D) {
892   VisitTypeDecl(D);
893   Writer.AddSourceLocation(D->getTypenameLoc(), Record);
894   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
895   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
896 }
897 
898 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
899   VisitRecordDecl(D);
900 
901   CXXRecordDecl *DefinitionDecl = 0;
902   if (D->DefinitionData)
903     DefinitionDecl = D->DefinitionData->Definition;
904   Writer.AddDeclRef(DefinitionDecl, Record);
905   if (D == DefinitionDecl)
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::VisitAccessSpecDecl(AccessSpecDecl *D) {
969   VisitDecl(D);
970   Writer.AddSourceLocation(D->getColonLoc(), Record);
971   Code = serialization::DECL_ACCESS_SPEC;
972 }
973 
974 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
975   VisitDecl(D);
976   Record.push_back(D->Friend.is<TypeSourceInfo*>());
977   if (D->Friend.is<TypeSourceInfo*>())
978     Writer.AddTypeSourceInfo(D->Friend.get<TypeSourceInfo*>(), Record);
979   else
980     Writer.AddDeclRef(D->Friend.get<NamedDecl*>(), Record);
981   Writer.AddDeclRef(D->getNextFriend(), Record);
982   Record.push_back(D->UnsupportedFriend);
983   Writer.AddSourceLocation(D->FriendLoc, Record);
984   Code = serialization::DECL_FRIEND;
985 }
986 
987 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
988   VisitDecl(D);
989   Record.push_back(D->getNumTemplateParameters());
990   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
991     Writer.AddTemplateParameterList(D->getTemplateParameterList(i), Record);
992   Record.push_back(D->getFriendDecl() != 0);
993   if (D->getFriendDecl())
994     Writer.AddDeclRef(D->getFriendDecl(), Record);
995   else
996     Writer.AddTypeSourceInfo(D->getFriendType(), Record);
997   Writer.AddSourceLocation(D->getFriendLoc(), Record);
998   Code = serialization::DECL_FRIEND_TEMPLATE;
999 }
1000 
1001 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
1002   VisitNamedDecl(D);
1003 
1004   Writer.AddDeclRef(D->getTemplatedDecl(), Record);
1005   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1006 }
1007 
1008 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
1009   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
1010   // getCommonPtr() can be used while this is still initializing.
1011 
1012   Writer.AddDeclRef(D->getPreviousDeclaration(), Record);
1013   if (D->getPreviousDeclaration())
1014     Writer.AddDeclRef(D->getFirstDeclaration(), Record);
1015 
1016   if (D->getPreviousDeclaration() == 0) {
1017     // This TemplateDecl owns the CommonPtr; write it.
1018     assert(D->isCanonicalDecl());
1019 
1020     Writer.AddDeclRef(D->getInstantiatedFromMemberTemplate(), Record);
1021     if (D->getInstantiatedFromMemberTemplate())
1022       Record.push_back(D->isMemberSpecialization());
1023 
1024     Writer.AddDeclRef(D->getCommonPtr()->Latest, Record);
1025   } else {
1026     RedeclarableTemplateDecl *First = D->getFirstDeclaration();
1027     assert(First != D);
1028     // If this is a most recent redeclaration that is pointed to by a first decl
1029     // in a chained PCH, keep track of the association with the map so we can
1030     // update the first decl during AST reading.
1031     if (First->getMostRecentDeclaration() == D &&
1032         First->isFromASTFile() && !D->isFromASTFile()) {
1033       assert(Writer.FirstLatestDecls.find(First)==Writer.FirstLatestDecls.end()
1034              && "The latest is already set");
1035       Writer.FirstLatestDecls[First] = D;
1036     }
1037   }
1038 
1039   VisitTemplateDecl(D);
1040   Record.push_back(D->getIdentifierNamespace());
1041 }
1042 
1043 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1044   VisitRedeclarableTemplateDecl(D);
1045 
1046   if (D->getPreviousDeclaration() == 0) {
1047     typedef llvm::FoldingSet<ClassTemplateSpecializationDecl> CTSDSetTy;
1048     CTSDSetTy &CTSDSet = D->getSpecializations();
1049     Record.push_back(CTSDSet.size());
1050     for (CTSDSetTy::iterator I=CTSDSet.begin(), E = CTSDSet.end(); I!=E; ++I) {
1051       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1052       Writer.AddDeclRef(&*I, Record);
1053     }
1054 
1055     typedef llvm::FoldingSet<ClassTemplatePartialSpecializationDecl> CTPSDSetTy;
1056     CTPSDSetTy &CTPSDSet = D->getPartialSpecializations();
1057     Record.push_back(CTPSDSet.size());
1058     for (CTPSDSetTy::iterator I=CTPSDSet.begin(), E=CTPSDSet.end(); I!=E; ++I) {
1059       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
1060       Writer.AddDeclRef(&*I, Record);
1061     }
1062 
1063     // InjectedClassNameType is computed, no need to write it.
1064   }
1065   Code = serialization::DECL_CLASS_TEMPLATE;
1066 }
1067 
1068 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
1069                                            ClassTemplateSpecializationDecl *D) {
1070   VisitCXXRecordDecl(D);
1071 
1072   llvm::PointerUnion<ClassTemplateDecl *,
1073                      ClassTemplatePartialSpecializationDecl *> InstFrom
1074     = D->getSpecializedTemplateOrPartial();
1075   if (Decl *InstFromD = InstFrom.dyn_cast<ClassTemplateDecl *>()) {
1076     Writer.AddDeclRef(InstFromD, Record);
1077   } else {
1078     Writer.AddDeclRef(InstFrom.get<ClassTemplatePartialSpecializationDecl *>(),
1079                       Record);
1080     Writer.AddTemplateArgumentList(&D->getTemplateInstantiationArgs(), Record);
1081   }
1082 
1083   // Explicit info.
1084   Writer.AddTypeSourceInfo(D->getTypeAsWritten(), Record);
1085   if (D->getTypeAsWritten()) {
1086     Writer.AddSourceLocation(D->getExternLoc(), Record);
1087     Writer.AddSourceLocation(D->getTemplateKeywordLoc(), Record);
1088   }
1089 
1090   Writer.AddTemplateArgumentList(&D->getTemplateArgs(), Record);
1091   Writer.AddSourceLocation(D->getPointOfInstantiation(), Record);
1092   Record.push_back(D->getSpecializationKind());
1093 
1094   if (D->isCanonicalDecl()) {
1095     // When reading, we'll add it to the folding set of the following template.
1096     Writer.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl(), Record);
1097   }
1098 
1099   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
1100 }
1101 
1102 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
1103                                     ClassTemplatePartialSpecializationDecl *D) {
1104   VisitClassTemplateSpecializationDecl(D);
1105 
1106   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
1107 
1108   Record.push_back(D->getNumTemplateArgsAsWritten());
1109   for (int i = 0, e = D->getNumTemplateArgsAsWritten(); i != e; ++i)
1110     Writer.AddTemplateArgumentLoc(D->getTemplateArgsAsWritten()[i], Record);
1111 
1112   Record.push_back(D->getSequenceNumber());
1113 
1114   // These are read/set from/to the first declaration.
1115   if (D->getPreviousDeclaration() == 0) {
1116     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
1117     Record.push_back(D->isMemberSpecialization());
1118   }
1119 
1120   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
1121 }
1122 
1123 void ASTDeclWriter::VisitClassScopeFunctionSpecializationDecl(
1124                                     ClassScopeFunctionSpecializationDecl *D) {
1125   VisitDecl(D);
1126   Writer.AddDeclRef(D->getSpecialization(), Record);
1127   Code = serialization::DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION;
1128 }
1129 
1130 
1131 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1132   VisitRedeclarableTemplateDecl(D);
1133 
1134   if (D->getPreviousDeclaration() == 0) {
1135     // This FunctionTemplateDecl owns the CommonPtr; write it.
1136 
1137     // Write the function specialization declarations.
1138     Record.push_back(D->getSpecializations().size());
1139     for (llvm::FoldingSet<FunctionTemplateSpecializationInfo>::iterator
1140            I = D->getSpecializations().begin(),
1141            E = D->getSpecializations().end()   ; I != E; ++I) {
1142       assert(I->Function->isCanonicalDecl() &&
1143              "Expected only canonical decls in set");
1144       Writer.AddDeclRef(I->Function, Record);
1145     }
1146   }
1147   Code = serialization::DECL_FUNCTION_TEMPLATE;
1148 }
1149 
1150 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1151   VisitTypeDecl(D);
1152 
1153   Record.push_back(D->wasDeclaredWithTypename());
1154   Record.push_back(D->defaultArgumentWasInherited());
1155   Writer.AddTypeSourceInfo(D->getDefaultArgumentInfo(), Record);
1156 
1157   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1158 }
1159 
1160 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1161   // For an expanded parameter pack, record the number of expansion types here
1162   // so that it's easier for
1163   if (D->isExpandedParameterPack())
1164     Record.push_back(D->getNumExpansionTypes());
1165 
1166   VisitDeclaratorDecl(D);
1167   // TemplateParmPosition.
1168   Record.push_back(D->getDepth());
1169   Record.push_back(D->getPosition());
1170 
1171   if (D->isExpandedParameterPack()) {
1172     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1173       Writer.AddTypeRef(D->getExpansionType(I), Record);
1174       Writer.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I), Record);
1175     }
1176 
1177     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1178   } else {
1179     // Rest of NonTypeTemplateParmDecl.
1180     Record.push_back(D->isParameterPack());
1181     Record.push_back(D->getDefaultArgument() != 0);
1182     if (D->getDefaultArgument()) {
1183       Writer.AddStmt(D->getDefaultArgument());
1184       Record.push_back(D->defaultArgumentWasInherited());
1185     }
1186     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1187   }
1188 }
1189 
1190 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1191   VisitTemplateDecl(D);
1192   // TemplateParmPosition.
1193   Record.push_back(D->getDepth());
1194   Record.push_back(D->getPosition());
1195   // Rest of TemplateTemplateParmDecl.
1196   Writer.AddTemplateArgumentLoc(D->getDefaultArgument(), Record);
1197   Record.push_back(D->defaultArgumentWasInherited());
1198   Record.push_back(D->isParameterPack());
1199   Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1200 }
1201 
1202 void ASTDeclWriter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
1203   VisitRedeclarableTemplateDecl(D);
1204   Code = serialization::DECL_TYPE_ALIAS_TEMPLATE;
1205 }
1206 
1207 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1208   VisitDecl(D);
1209   Writer.AddStmt(D->getAssertExpr());
1210   Writer.AddStmt(D->getMessage());
1211   Writer.AddSourceLocation(D->getRParenLoc(), Record);
1212   Code = serialization::DECL_STATIC_ASSERT;
1213 }
1214 
1215 /// \brief Emit the DeclContext part of a declaration context decl.
1216 ///
1217 /// \param LexicalOffset the offset at which the DECL_CONTEXT_LEXICAL
1218 /// block for this declaration context is stored. May be 0 to indicate
1219 /// that there are no declarations stored within this context.
1220 ///
1221 /// \param VisibleOffset the offset at which the DECL_CONTEXT_VISIBLE
1222 /// block for this declaration context is stored. May be 0 to indicate
1223 /// that there are no declarations visible from this context. Note
1224 /// that this value will not be emitted for non-primary declaration
1225 /// contexts.
1226 void ASTDeclWriter::VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
1227                                      uint64_t VisibleOffset) {
1228   Record.push_back(LexicalOffset);
1229   Record.push_back(VisibleOffset);
1230 }
1231 
1232 template <typename T>
1233 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1234   enum { NoRedeclaration = 0, PointsToPrevious, PointsToLatest };
1235   if (D->RedeclLink.getNext() == D) {
1236     Record.push_back(NoRedeclaration);
1237   } else {
1238     if (D->RedeclLink.NextIsPrevious()) {
1239       Record.push_back(PointsToPrevious);
1240       Writer.AddDeclRef(D->getPreviousDeclaration(), Record);
1241       Writer.AddDeclRef(D->getFirstDeclaration(), Record);
1242     } else {
1243       Record.push_back(PointsToLatest);
1244       Writer.AddDeclRef(D->RedeclLink.getPointer(), Record);
1245     }
1246   }
1247 
1248   T *First = D->getFirstDeclaration();
1249   T *ThisDecl = static_cast<T*>(D);
1250   // If this is a most recent redeclaration that is pointed to by a first decl
1251   // in a chained PCH, keep track of the association with the map so we can
1252   // update the first decl during AST reading.
1253   if (ThisDecl != First && First->getMostRecentDeclaration() == ThisDecl &&
1254       First->isFromASTFile() && !ThisDecl->isFromASTFile()) {
1255     assert(Writer.FirstLatestDecls.find(First) == Writer.FirstLatestDecls.end()
1256            && "The latest is already set");
1257     Writer.FirstLatestDecls[First] = ThisDecl;
1258   }
1259 }
1260 
1261 //===----------------------------------------------------------------------===//
1262 // ASTWriter Implementation
1263 //===----------------------------------------------------------------------===//
1264 
1265 void ASTWriter::WriteDeclsBlockAbbrevs() {
1266   using namespace llvm;
1267 
1268   BitCodeAbbrev *Abv;
1269 
1270   // Abbreviation for DECL_FIELD
1271   Abv = new BitCodeAbbrev();
1272   Abv->Add(BitCodeAbbrevOp(serialization::DECL_FIELD));
1273   // Decl
1274   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1275   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1276   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1277   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1278   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1279   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1280   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1281   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1282   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1283   // NamedDecl
1284   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1285   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1286   // ValueDecl
1287   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1288   // DeclaratorDecl
1289   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1290   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1291   // FieldDecl
1292   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1293   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1294   // Type Source Info
1295   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1296   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1297   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1298   DeclFieldAbbrev = Stream.EmitAbbrev(Abv);
1299 
1300   // Abbreviation for DECL_OBJC_IVAR
1301   Abv = new BitCodeAbbrev();
1302   Abv->Add(BitCodeAbbrevOp(serialization::DECL_OBJC_IVAR));
1303   // Decl
1304   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1305   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1306   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1307   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1308   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1309   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1310   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1311   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1312   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1313   // NamedDecl
1314   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1315   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1316   // ValueDecl
1317   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1318   // DeclaratorDecl
1319   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1320   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1321   // FieldDecl
1322   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1323   Abv->Add(BitCodeAbbrevOp(0));                       //getBitWidth
1324   // ObjC Ivar
1325   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getAccessControl
1326   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getSynthesize
1327   // Type Source Info
1328   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1329   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1330   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1331   DeclObjCIvarAbbrev = Stream.EmitAbbrev(Abv);
1332 
1333   // Abbreviation for DECL_ENUM
1334   Abv = new BitCodeAbbrev();
1335   Abv->Add(BitCodeAbbrevOp(serialization::DECL_ENUM));
1336   // Redeclarable
1337   Abv->Add(BitCodeAbbrevOp(0));                         // No redeclaration
1338   // Decl
1339   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1340   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1341   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1342   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1343   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1344   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1345   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1346   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1347   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1348   // NamedDecl
1349   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1350   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1351   // TypeDecl
1352   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1353   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1354   // TagDecl
1355   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1356   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1357   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1358   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1359   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1360   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1361   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1362   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1363   // EnumDecl
1364   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddTypeRef
1365   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IntegerType
1366   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getPromotionType
1367   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumPositiveBits
1368   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumNegativeBits
1369   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScoped
1370   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScopedUsingClassTag
1371   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isFixed
1372   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InstantiatedMembEnum
1373   // DC
1374   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1375   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1376   DeclEnumAbbrev = Stream.EmitAbbrev(Abv);
1377 
1378   // Abbreviation for DECL_RECORD
1379   Abv = new BitCodeAbbrev();
1380   Abv->Add(BitCodeAbbrevOp(serialization::DECL_RECORD));
1381   // Redeclarable
1382   Abv->Add(BitCodeAbbrevOp(0));                         // No redeclaration
1383   // Decl
1384   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1385   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1386   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1387   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1388   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1389   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1390   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1391   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1392   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1393   // NamedDecl
1394   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1395   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1396   // TypeDecl
1397   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1398   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1399   // TagDecl
1400   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1401   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1402   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1403   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1404   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1405   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1406   Abv->Add(BitCodeAbbrevOp(0));                         // hasExtInfo
1407   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // TypedefNameAnonDecl
1408   // RecordDecl
1409   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // FlexibleArrayMember
1410   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // AnonymousStructUnion
1411   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasObjectMember
1412   // DC
1413   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1414   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1415   DeclRecordAbbrev = Stream.EmitAbbrev(Abv);
1416 
1417   // Abbreviation for DECL_PARM_VAR
1418   Abv = new BitCodeAbbrev();
1419   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1420   // Redeclarable
1421   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1422   // Decl
1423   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1424   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1425   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1426   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1427   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1428   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1429   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1430   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1431   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
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   // Decl
1469   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1470   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1471   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1472   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1473   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1474   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1475   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1476   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1477   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1478   // NamedDecl
1479   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1480   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1481   // TypeDecl
1482   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1483   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1484   // TypedefDecl
1485   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1486   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1487   DeclTypedefAbbrev = Stream.EmitAbbrev(Abv);
1488 
1489   // Abbreviation for DECL_VAR
1490   Abv = new BitCodeAbbrev();
1491   Abv->Add(BitCodeAbbrevOp(serialization::DECL_VAR));
1492   // Redeclarable
1493   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1494   // Decl
1495   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1496   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1497   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1498   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1499   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1500   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1501   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1502   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1503   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1504   // NamedDecl
1505   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1506   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1507   // ValueDecl
1508   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1509   // DeclaratorDecl
1510   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1511   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1512   // VarDecl
1513   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClass
1514   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClassAsWritten
1515   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isThreadSpecified
1516   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // CXXDirectInitializer
1517   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
1518   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
1519   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
1520   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
1521   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasInit
1522   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasMemberSpecInfo
1523   // Type Source Info
1524   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1525   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1526   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1527   DeclVarAbbrev = Stream.EmitAbbrev(Abv);
1528 
1529   // Abbreviation for EXPR_DECL_REF
1530   Abv = new BitCodeAbbrev();
1531   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_DECL_REF));
1532   //Stmt
1533   //Expr
1534   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1535   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1536   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1537   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1538   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1539   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1540   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1541   //DeclRefExpr
1542   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HasQualifier
1543   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //GetDeclFound
1544   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ExplicitTemplateArgs
1545   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HadMultipleCandidates
1546   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclRef
1547   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1548   DeclRefExprAbbrev = Stream.EmitAbbrev(Abv);
1549 
1550   // Abbreviation for EXPR_INTEGER_LITERAL
1551   Abv = new BitCodeAbbrev();
1552   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_INTEGER_LITERAL));
1553   //Stmt
1554   //Expr
1555   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1556   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1557   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1558   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1559   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1560   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1561   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1562   //Integer Literal
1563   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1564   Abv->Add(BitCodeAbbrevOp(32));                      // Bit Width
1565   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Value
1566   IntegerLiteralAbbrev = Stream.EmitAbbrev(Abv);
1567 
1568   // Abbreviation for EXPR_CHARACTER_LITERAL
1569   Abv = new BitCodeAbbrev();
1570   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_CHARACTER_LITERAL));
1571   //Stmt
1572   //Expr
1573   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1574   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
1575   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
1576   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
1577   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
1578   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
1579   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
1580   //Character Literal
1581   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getValue
1582   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1583   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //IsWide
1584   CharacterLiteralAbbrev = Stream.EmitAbbrev(Abv);
1585 
1586   Abv = new BitCodeAbbrev();
1587   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
1588   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1589   DeclContextLexicalAbbrev = Stream.EmitAbbrev(Abv);
1590 
1591   Abv = new BitCodeAbbrev();
1592   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
1593   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1594   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1595   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(Abv);
1596 }
1597 
1598 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
1599 /// consumers of the AST.
1600 ///
1601 /// Such decls will always be deserialized from the AST file, so we would like
1602 /// this to be as restrictive as possible. Currently the predicate is driven by
1603 /// code generation requirements, if other clients have a different notion of
1604 /// what is "required" then we may have to consider an alternate scheme where
1605 /// clients can iterate over the top-level decls and get information on them,
1606 /// without necessary deserializing them. We could explicitly require such
1607 /// clients to use a separate API call to "realize" the decl. This should be
1608 /// relatively painless since they would presumably only do it for top-level
1609 /// decls.
1610 static bool isRequiredDecl(const Decl *D, ASTContext &Context) {
1611   // An ObjCMethodDecl is never considered as "required" because its
1612   // implementation container always is.
1613 
1614   // File scoped assembly or obj-c implementation must be seen.
1615   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplDecl>(D))
1616     return true;
1617 
1618   return Context.DeclMustBeEmitted(D);
1619 }
1620 
1621 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
1622   // Switch case IDs are per Decl.
1623   ClearSwitchCaseIDs();
1624 
1625   RecordData Record;
1626   ASTDeclWriter W(*this, Context, Record);
1627 
1628   // If this declaration is also a DeclContext, write blocks for the
1629   // declarations that lexically stored inside its context and those
1630   // declarations that are visible from its context. These blocks
1631   // are written before the declaration itself so that we can put
1632   // their offsets into the record for the declaration.
1633   uint64_t LexicalOffset = 0;
1634   uint64_t VisibleOffset = 0;
1635   DeclContext *DC = dyn_cast<DeclContext>(D);
1636   if (DC) {
1637     LexicalOffset = WriteDeclContextLexicalBlock(Context, DC);
1638     VisibleOffset = WriteDeclContextVisibleBlock(Context, DC);
1639   }
1640 
1641   // Determine the ID for this declaration
1642   serialization::DeclID &IDR = DeclIDs[D];
1643   if (IDR == 0)
1644     IDR = NextDeclID++;
1645   serialization::DeclID ID = IDR;
1646 
1647   if (ID < FirstDeclID) {
1648     // We're replacing a decl in a previous file.
1649     ReplacedDecls.push_back(ReplacedDeclInfo(ID, Stream.GetCurrentBitNo(),
1650                                              D->getLocation()));
1651   } else {
1652     unsigned Index = ID - FirstDeclID;
1653 
1654     // Record the offset for this declaration
1655     SourceLocation Loc = D->getLocation();
1656     if (DeclOffsets.size() == Index)
1657       DeclOffsets.push_back(DeclOffset(Loc, Stream.GetCurrentBitNo()));
1658     else if (DeclOffsets.size() < Index) {
1659       DeclOffsets.resize(Index+1);
1660       DeclOffsets[Index].setLocation(Loc);
1661       DeclOffsets[Index].BitOffset = Stream.GetCurrentBitNo();
1662     }
1663 
1664     SourceManager &SM = Context.getSourceManager();
1665     if (Loc.isValid() && SM.isLocalSourceLocation(Loc))
1666       associateDeclWithFile(D, ID);
1667   }
1668 
1669   // Build and emit a record for this declaration
1670   Record.clear();
1671   W.Code = (serialization::DeclCode)0;
1672   W.AbbrevToUse = 0;
1673   W.Visit(D);
1674   if (DC) W.VisitDeclContext(DC, LexicalOffset, VisibleOffset);
1675 
1676   if (!W.Code)
1677     llvm::report_fatal_error(StringRef("unexpected declaration kind '") +
1678                             D->getDeclKindName() + "'");
1679   Stream.EmitRecord(W.Code, Record, W.AbbrevToUse);
1680 
1681   // Flush any expressions that were written as part of this declaration.
1682   FlushStmts();
1683 
1684   // Flush C++ base specifiers, if there are any.
1685   FlushCXXBaseSpecifiers();
1686 
1687   // Note "external" declarations so that we can add them to a record in the
1688   // AST file later.
1689   //
1690   // FIXME: This should be renamed, the predicate is much more complicated.
1691   if (isRequiredDecl(D, Context))
1692     ExternalDefinitions.push_back(ID);
1693 }
1694