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