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 "clang/AST/DeclVisitor.h"
16 #include "clang/AST/DeclCXX.h"
17 #include "clang/AST/DeclTemplate.h"
18 #include "clang/AST/Expr.h"
19 #include "clang/AST/DeclContextInternals.h"
20 #include "llvm/ADT/Twine.h"
21 #include "llvm/Bitcode/BitstreamWriter.h"
22 #include "llvm/Support/ErrorHandling.h"
23 using namespace clang;
24 
25 //===----------------------------------------------------------------------===//
26 // Declaration serialization
27 //===----------------------------------------------------------------------===//
28 
29 namespace clang {
30   class ASTDeclWriter : public DeclVisitor<ASTDeclWriter, void> {
31 
32     ASTWriter &Writer;
33     ASTContext &Context;
34     typedef ASTWriter::RecordData RecordData;
35     RecordData &Record;
36 
37   public:
38     serialization::DeclCode Code;
39     unsigned AbbrevToUse;
40 
41     ASTDeclWriter(ASTWriter &Writer, ASTContext &Context, RecordData &Record)
42       : Writer(Writer), Context(Context), Record(Record) {
43     }
44 
45     void Visit(Decl *D);
46 
47     void VisitDecl(Decl *D);
48     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
49     void VisitNamedDecl(NamedDecl *D);
50     void VisitLabelDecl(LabelDecl *LD);
51     void VisitNamespaceDecl(NamespaceDecl *D);
52     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
53     void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
54     void VisitTypeDecl(TypeDecl *D);
55     void VisitTypedefDecl(TypedefDecl *D);
56     void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
57     void VisitTagDecl(TagDecl *D);
58     void VisitEnumDecl(EnumDecl *D);
59     void VisitRecordDecl(RecordDecl *D);
60     void VisitCXXRecordDecl(CXXRecordDecl *D);
61     void VisitClassTemplateSpecializationDecl(
62                                             ClassTemplateSpecializationDecl *D);
63     void VisitClassTemplatePartialSpecializationDecl(
64                                      ClassTemplatePartialSpecializationDecl *D);
65     void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
66     void VisitValueDecl(ValueDecl *D);
67     void VisitEnumConstantDecl(EnumConstantDecl *D);
68     void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
69     void VisitDeclaratorDecl(DeclaratorDecl *D);
70     void VisitFunctionDecl(FunctionDecl *D);
71     void VisitCXXMethodDecl(CXXMethodDecl *D);
72     void VisitCXXConstructorDecl(CXXConstructorDecl *D);
73     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
74     void VisitCXXConversionDecl(CXXConversionDecl *D);
75     void VisitFieldDecl(FieldDecl *D);
76     void VisitIndirectFieldDecl(IndirectFieldDecl *D);
77     void VisitVarDecl(VarDecl *D);
78     void VisitImplicitParamDecl(ImplicitParamDecl *D);
79     void VisitParmVarDecl(ParmVarDecl *D);
80     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
81     void VisitTemplateDecl(TemplateDecl *D);
82     void VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
83     void VisitClassTemplateDecl(ClassTemplateDecl *D);
84     void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
85     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
86     void VisitUsingDecl(UsingDecl *D);
87     void VisitUsingShadowDecl(UsingShadowDecl *D);
88     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
89     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
90     void VisitAccessSpecDecl(AccessSpecDecl *D);
91     void VisitFriendDecl(FriendDecl *D);
92     void VisitFriendTemplateDecl(FriendTemplateDecl *D);
93     void VisitStaticAssertDecl(StaticAssertDecl *D);
94     void VisitBlockDecl(BlockDecl *D);
95 
96     void VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
97                           uint64_t VisibleOffset);
98     template <typename T> void VisitRedeclarable(Redeclarable<T> *D);
99 
100 
101     // FIXME: Put in the same order is DeclNodes.td?
102     void VisitObjCMethodDecl(ObjCMethodDecl *D);
103     void VisitObjCContainerDecl(ObjCContainerDecl *D);
104     void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
105     void VisitObjCIvarDecl(ObjCIvarDecl *D);
106     void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
107     void VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D);
108     void VisitObjCClassDecl(ObjCClassDecl *D);
109     void VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *D);
110     void VisitObjCCategoryDecl(ObjCCategoryDecl *D);
111     void VisitObjCImplDecl(ObjCImplDecl *D);
112     void VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D);
113     void VisitObjCImplementationDecl(ObjCImplementationDecl *D);
114     void VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D);
115     void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
116     void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
117   };
118 }
119 
120 void ASTDeclWriter::Visit(Decl *D) {
121   DeclVisitor<ASTDeclWriter>::Visit(D);
122 
123   // Handle FunctionDecl's body here and write it after all other Stmts/Exprs
124   // have been written. We want it last because we will not read it back when
125   // retrieving it from the AST, we'll just lazily set the offset.
126   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
127     Record.push_back(FD->isThisDeclarationADefinition());
128     if (FD->isThisDeclarationADefinition())
129       Writer.AddStmt(FD->getBody());
130   }
131 }
132 
133 void ASTDeclWriter::VisitDecl(Decl *D) {
134   Writer.AddDeclRef(cast_or_null<Decl>(D->getDeclContext()), Record);
135   Writer.AddDeclRef(cast_or_null<Decl>(D->getLexicalDeclContext()), Record);
136   Writer.AddSourceLocation(D->getLocation(), Record);
137   Record.push_back(D->isInvalidDecl());
138   Record.push_back(D->hasAttrs());
139   if (D->hasAttrs())
140     Writer.WriteAttributes(D->getAttrs(), Record);
141   Record.push_back(D->isImplicit());
142   Record.push_back(D->isUsed(false));
143   Record.push_back(D->getAccess());
144   Record.push_back(D->getPCHLevel());
145 }
146 
147 void ASTDeclWriter::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
148   VisitDecl(D);
149   Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
150   Code = serialization::DECL_TRANSLATION_UNIT;
151 }
152 
153 void ASTDeclWriter::VisitNamedDecl(NamedDecl *D) {
154   VisitDecl(D);
155   Writer.AddDeclarationName(D->getDeclName(), Record);
156 }
157 
158 void ASTDeclWriter::VisitTypeDecl(TypeDecl *D) {
159   VisitNamedDecl(D);
160   Writer.AddSourceLocation(D->getLocStart(), Record);
161   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
162 }
163 
164 void ASTDeclWriter::VisitTypedefDecl(TypedefDecl *D) {
165   VisitTypeDecl(D);
166   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
167   Code = serialization::DECL_TYPEDEF;
168 }
169 
170 void ASTDeclWriter::VisitTagDecl(TagDecl *D) {
171   VisitTypeDecl(D);
172   VisitRedeclarable(D);
173   Record.push_back(D->getIdentifierNamespace());
174   Record.push_back((unsigned)D->getTagKind()); // FIXME: stable encoding
175   Record.push_back(D->isDefinition());
176   Record.push_back(D->isEmbeddedInDeclarator());
177   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
178   Record.push_back(D->hasExtInfo());
179   if (D->hasExtInfo())
180     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
181   else
182     Writer.AddDeclRef(D->getTypedefForAnonDecl(), Record);
183 }
184 
185 void ASTDeclWriter::VisitEnumDecl(EnumDecl *D) {
186   VisitTagDecl(D);
187   Writer.AddTypeSourceInfo(D->getIntegerTypeSourceInfo(), Record);
188   if (!D->getIntegerTypeSourceInfo())
189     Writer.AddTypeRef(D->getIntegerType(), Record);
190   Writer.AddTypeRef(D->getPromotionType(), Record);
191   Record.push_back(D->getNumPositiveBits());
192   Record.push_back(D->getNumNegativeBits());
193   Record.push_back(D->isScoped());
194   Record.push_back(D->isScopedUsingClassTag());
195   Record.push_back(D->isFixed());
196   Writer.AddDeclRef(D->getInstantiatedFromMemberEnum(), Record);
197   Code = serialization::DECL_ENUM;
198 }
199 
200 void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
201   VisitTagDecl(D);
202   Record.push_back(D->hasFlexibleArrayMember());
203   Record.push_back(D->isAnonymousStructOrUnion());
204   Record.push_back(D->hasObjectMember());
205   Code = serialization::DECL_RECORD;
206 }
207 
208 void ASTDeclWriter::VisitValueDecl(ValueDecl *D) {
209   VisitNamedDecl(D);
210   Writer.AddTypeRef(D->getType(), Record);
211 }
212 
213 void ASTDeclWriter::VisitEnumConstantDecl(EnumConstantDecl *D) {
214   VisitValueDecl(D);
215   Record.push_back(D->getInitExpr()? 1 : 0);
216   if (D->getInitExpr())
217     Writer.AddStmt(D->getInitExpr());
218   Writer.AddAPSInt(D->getInitVal(), Record);
219   Code = serialization::DECL_ENUM_CONSTANT;
220 }
221 
222 void ASTDeclWriter::VisitDeclaratorDecl(DeclaratorDecl *D) {
223   VisitValueDecl(D);
224   Writer.AddSourceLocation(D->getInnerLocStart(), Record);
225   Record.push_back(D->hasExtInfo());
226   if (D->hasExtInfo())
227     Writer.AddQualifierInfo(*D->getExtInfo(), Record);
228   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
229 }
230 
231 void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
232   VisitDeclaratorDecl(D);
233   VisitRedeclarable(D);
234 
235   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
236   Record.push_back(D->getIdentifierNamespace());
237   Record.push_back(D->getTemplatedKind());
238   switch (D->getTemplatedKind()) {
239   default: assert(false && "Unhandled TemplatedKind!");
240     break;
241   case FunctionDecl::TK_NonTemplate:
242     break;
243   case FunctionDecl::TK_FunctionTemplate:
244     Writer.AddDeclRef(D->getDescribedFunctionTemplate(), Record);
245     break;
246   case FunctionDecl::TK_MemberSpecialization: {
247     MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo();
248     Writer.AddDeclRef(MemberInfo->getInstantiatedFrom(), Record);
249     Record.push_back(MemberInfo->getTemplateSpecializationKind());
250     Writer.AddSourceLocation(MemberInfo->getPointOfInstantiation(), Record);
251     break;
252   }
253   case FunctionDecl::TK_FunctionTemplateSpecialization: {
254     FunctionTemplateSpecializationInfo *
255       FTSInfo = D->getTemplateSpecializationInfo();
256     Writer.AddDeclRef(FTSInfo->getTemplate(), Record);
257     Record.push_back(FTSInfo->getTemplateSpecializationKind());
258 
259     // Template arguments.
260     Writer.AddTemplateArgumentList(FTSInfo->TemplateArguments, Record);
261 
262     // Template args as written.
263     Record.push_back(FTSInfo->TemplateArgumentsAsWritten != 0);
264     if (FTSInfo->TemplateArgumentsAsWritten) {
265       Record.push_back(FTSInfo->TemplateArgumentsAsWritten->size());
266       for (int i=0, e = FTSInfo->TemplateArgumentsAsWritten->size(); i!=e; ++i)
267         Writer.AddTemplateArgumentLoc((*FTSInfo->TemplateArgumentsAsWritten)[i],
268                                       Record);
269       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->getLAngleLoc(),
270                                Record);
271       Writer.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->getRAngleLoc(),
272                                Record);
273     }
274 
275     Writer.AddSourceLocation(FTSInfo->getPointOfInstantiation(), Record);
276 
277     if (D->isCanonicalDecl()) {
278       // Write the template that contains the specializations set. We will
279       // add a FunctionTemplateSpecializationInfo to it when reading.
280       Writer.AddDeclRef(FTSInfo->getTemplate()->getCanonicalDecl(), Record);
281     }
282     break;
283   }
284   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
285     DependentFunctionTemplateSpecializationInfo *
286       DFTSInfo = D->getDependentSpecializationInfo();
287 
288     // Templates.
289     Record.push_back(DFTSInfo->getNumTemplates());
290     for (int i=0, e = DFTSInfo->getNumTemplates(); i != e; ++i)
291       Writer.AddDeclRef(DFTSInfo->getTemplate(i), Record);
292 
293     // Templates args.
294     Record.push_back(DFTSInfo->getNumTemplateArgs());
295     for (int i=0, e = DFTSInfo->getNumTemplateArgs(); i != e; ++i)
296       Writer.AddTemplateArgumentLoc(DFTSInfo->getTemplateArg(i), Record);
297     Writer.AddSourceLocation(DFTSInfo->getLAngleLoc(), Record);
298     Writer.AddSourceLocation(DFTSInfo->getRAngleLoc(), Record);
299     break;
300   }
301   }
302 
303   // FunctionDecl's body is handled last at ASTWriterDecl::Visit,
304   // after everything else is written.
305 
306   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
307   Record.push_back(D->getStorageClassAsWritten());
308   Record.push_back(D->IsInline);
309   Record.push_back(D->isInlineSpecified());
310   Record.push_back(D->isVirtualAsWritten());
311   Record.push_back(D->isPure());
312   Record.push_back(D->hasInheritedPrototype());
313   Record.push_back(D->hasWrittenPrototype());
314   Record.push_back(D->isDeleted());
315   Record.push_back(D->isTrivial());
316   Record.push_back(D->hasImplicitReturnZero());
317   Writer.AddSourceLocation(D->getLocEnd(), Record);
318 
319   Record.push_back(D->param_size());
320   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
321        P != PEnd; ++P)
322     Writer.AddDeclRef(*P, Record);
323   Code = serialization::DECL_FUNCTION;
324 }
325 
326 void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
327   VisitNamedDecl(D);
328   // FIXME: convert to LazyStmtPtr?
329   // Unlike C/C++, method bodies will never be in header files.
330   bool HasBodyStuff = D->getBody() != 0     ||
331                       D->getSelfDecl() != 0 || D->getCmdDecl() != 0;
332   Record.push_back(HasBodyStuff);
333   if (HasBodyStuff) {
334     Writer.AddStmt(D->getBody());
335     Writer.AddDeclRef(D->getSelfDecl(), Record);
336     Writer.AddDeclRef(D->getCmdDecl(), Record);
337   }
338   Record.push_back(D->isInstanceMethod());
339   Record.push_back(D->isVariadic());
340   Record.push_back(D->isSynthesized());
341   Record.push_back(D->isDefined());
342   // FIXME: stable encoding for @required/@optional
343   Record.push_back(D->getImplementationControl());
344   // FIXME: stable encoding for in/out/inout/bycopy/byref/oneway
345   Record.push_back(D->getObjCDeclQualifier());
346   Record.push_back(D->getNumSelectorArgs());
347   Writer.AddTypeRef(D->getResultType(), Record);
348   Writer.AddTypeSourceInfo(D->getResultTypeSourceInfo(), Record);
349   Writer.AddSourceLocation(D->getLocEnd(), Record);
350   Record.push_back(D->param_size());
351   for (ObjCMethodDecl::param_iterator P = D->param_begin(),
352                                    PEnd = D->param_end(); P != PEnd; ++P)
353     Writer.AddDeclRef(*P, Record);
354   Code = serialization::DECL_OBJC_METHOD;
355 }
356 
357 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
358   VisitNamedDecl(D);
359   Writer.AddSourceRange(D->getAtEndRange(), Record);
360   // Abstract class (no need to define a stable serialization::DECL code).
361 }
362 
363 void ASTDeclWriter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
364   VisitObjCContainerDecl(D);
365   Writer.AddTypeRef(QualType(D->getTypeForDecl(), 0), Record);
366   Writer.AddDeclRef(D->getSuperClass(), Record);
367 
368   // Write out the protocols that are directly referenced by the @interface.
369   Record.push_back(D->ReferencedProtocols.size());
370   for (ObjCInterfaceDecl::protocol_iterator P = D->protocol_begin(),
371          PEnd = D->protocol_end();
372        P != PEnd; ++P)
373     Writer.AddDeclRef(*P, Record);
374   for (ObjCInterfaceDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
375          PLEnd = D->protocol_loc_end();
376        PL != PLEnd; ++PL)
377     Writer.AddSourceLocation(*PL, Record);
378 
379   // Write out the protocols that are transitively referenced.
380   Record.push_back(D->AllReferencedProtocols.size());
381   for (ObjCList<ObjCProtocolDecl>::iterator
382         P = D->AllReferencedProtocols.begin(),
383         PEnd = D->AllReferencedProtocols.end();
384        P != PEnd; ++P)
385     Writer.AddDeclRef(*P, Record);
386 
387   // Write out the ivars.
388   Record.push_back(D->ivar_size());
389   for (ObjCInterfaceDecl::ivar_iterator I = D->ivar_begin(),
390                                      IEnd = D->ivar_end(); I != IEnd; ++I)
391     Writer.AddDeclRef(*I, Record);
392   Writer.AddDeclRef(D->getCategoryList(), Record);
393   Record.push_back(D->isForwardDecl());
394   Record.push_back(D->isImplicitInterfaceDecl());
395   Writer.AddSourceLocation(D->getClassLoc(), Record);
396   Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
397   Writer.AddSourceLocation(D->getLocEnd(), Record);
398   Code = serialization::DECL_OBJC_INTERFACE;
399 }
400 
401 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
402   VisitFieldDecl(D);
403   // FIXME: stable encoding for @public/@private/@protected/@package
404   Record.push_back(D->getAccessControl());
405   Record.push_back(D->getSynthesize());
406   Code = serialization::DECL_OBJC_IVAR;
407 }
408 
409 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
410   VisitObjCContainerDecl(D);
411   Record.push_back(D->isForwardDecl());
412   Writer.AddSourceLocation(D->getLocEnd(), Record);
413   Record.push_back(D->protocol_size());
414   for (ObjCProtocolDecl::protocol_iterator
415        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
416     Writer.AddDeclRef(*I, Record);
417   for (ObjCProtocolDecl::protocol_loc_iterator PL = D->protocol_loc_begin(),
418          PLEnd = D->protocol_loc_end();
419        PL != PLEnd; ++PL)
420     Writer.AddSourceLocation(*PL, Record);
421   Code = serialization::DECL_OBJC_PROTOCOL;
422 }
423 
424 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
425   VisitFieldDecl(D);
426   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
427 }
428 
429 void ASTDeclWriter::VisitObjCClassDecl(ObjCClassDecl *D) {
430   VisitDecl(D);
431   Record.push_back(D->size());
432   for (ObjCClassDecl::iterator I = D->begin(), IEnd = D->end(); I != IEnd; ++I)
433     Writer.AddDeclRef(I->getInterface(), Record);
434   for (ObjCClassDecl::iterator I = D->begin(), IEnd = D->end(); I != IEnd; ++I)
435     Writer.AddSourceLocation(I->getLocation(), Record);
436   Code = serialization::DECL_OBJC_CLASS;
437 }
438 
439 void ASTDeclWriter::VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *D) {
440   VisitDecl(D);
441   Record.push_back(D->protocol_size());
442   for (ObjCForwardProtocolDecl::protocol_iterator
443        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
444     Writer.AddDeclRef(*I, Record);
445   for (ObjCForwardProtocolDecl::protocol_loc_iterator
446          PL = D->protocol_loc_begin(), PLEnd = D->protocol_loc_end();
447        PL != PLEnd; ++PL)
448     Writer.AddSourceLocation(*PL, Record);
449   Code = serialization::DECL_OBJC_FORWARD_PROTOCOL;
450 }
451 
452 void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
453   VisitObjCContainerDecl(D);
454   Writer.AddDeclRef(D->getClassInterface(), Record);
455   Record.push_back(D->protocol_size());
456   for (ObjCCategoryDecl::protocol_iterator
457        I = D->protocol_begin(), IEnd = D->protocol_end(); I != IEnd; ++I)
458     Writer.AddDeclRef(*I, Record);
459   for (ObjCCategoryDecl::protocol_loc_iterator
460          PL = D->protocol_loc_begin(), PLEnd = D->protocol_loc_end();
461        PL != PLEnd; ++PL)
462     Writer.AddSourceLocation(*PL, Record);
463   Writer.AddDeclRef(D->getNextClassCategory(), Record);
464   Record.push_back(D->hasSynthBitfield());
465   Writer.AddSourceLocation(D->getAtLoc(), Record);
466   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
467   Code = serialization::DECL_OBJC_CATEGORY;
468 }
469 
470 void ASTDeclWriter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D) {
471   VisitNamedDecl(D);
472   Writer.AddDeclRef(D->getClassInterface(), Record);
473   Code = serialization::DECL_OBJC_COMPATIBLE_ALIAS;
474 }
475 
476 void ASTDeclWriter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
477   VisitNamedDecl(D);
478   Writer.AddSourceLocation(D->getAtLoc(), Record);
479   Writer.AddTypeSourceInfo(D->getTypeSourceInfo(), Record);
480   // FIXME: stable encoding
481   Record.push_back((unsigned)D->getPropertyAttributes());
482   Record.push_back((unsigned)D->getPropertyAttributesAsWritten());
483   // FIXME: stable encoding
484   Record.push_back((unsigned)D->getPropertyImplementation());
485   Writer.AddDeclarationName(D->getGetterName(), Record);
486   Writer.AddDeclarationName(D->getSetterName(), Record);
487   Writer.AddDeclRef(D->getGetterMethodDecl(), Record);
488   Writer.AddDeclRef(D->getSetterMethodDecl(), Record);
489   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
490   Code = serialization::DECL_OBJC_PROPERTY;
491 }
492 
493 void ASTDeclWriter::VisitObjCImplDecl(ObjCImplDecl *D) {
494   VisitObjCContainerDecl(D);
495   Writer.AddDeclRef(D->getClassInterface(), Record);
496   // Abstract class (no need to define a stable serialization::DECL code).
497 }
498 
499 void ASTDeclWriter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
500   VisitObjCImplDecl(D);
501   Writer.AddIdentifierRef(D->getIdentifier(), Record);
502   Code = serialization::DECL_OBJC_CATEGORY_IMPL;
503 }
504 
505 void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
506   VisitObjCImplDecl(D);
507   Writer.AddDeclRef(D->getSuperClass(), Record);
508   Writer.AddCXXCtorInitializers(D->IvarInitializers, D->NumIvarInitializers,
509                                 Record);
510   Record.push_back(D->hasSynthBitfield());
511   Code = serialization::DECL_OBJC_IMPLEMENTATION;
512 }
513 
514 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
515   VisitDecl(D);
516   Writer.AddSourceLocation(D->getLocStart(), Record);
517   Writer.AddDeclRef(D->getPropertyDecl(), Record);
518   Writer.AddDeclRef(D->getPropertyIvarDecl(), Record);
519   Writer.AddSourceLocation(D->getPropertyIvarDeclLoc(), Record);
520   Writer.AddStmt(D->getGetterCXXConstructor());
521   Writer.AddStmt(D->getSetterCXXAssignment());
522   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
523 }
524 
525 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
526   VisitDeclaratorDecl(D);
527   Record.push_back(D->isMutable());
528   Record.push_back(D->getBitWidth()? 1 : 0);
529   if (D->getBitWidth())
530     Writer.AddStmt(D->getBitWidth());
531   if (!D->getDeclName())
532     Writer.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D), Record);
533   Code = serialization::DECL_FIELD;
534 }
535 
536 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
537   VisitValueDecl(D);
538   Record.push_back(D->getChainingSize());
539 
540   for (IndirectFieldDecl::chain_iterator
541        P = D->chain_begin(),
542        PEnd = D->chain_end(); P != PEnd; ++P)
543     Writer.AddDeclRef(*P, Record);
544   Code = serialization::DECL_INDIRECTFIELD;
545 }
546 
547 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
548   VisitDeclaratorDecl(D);
549   VisitRedeclarable(D);
550   Record.push_back(D->getStorageClass()); // FIXME: stable encoding
551   Record.push_back(D->getStorageClassAsWritten());
552   Record.push_back(D->isThreadSpecified());
553   Record.push_back(D->hasCXXDirectInitializer());
554   Record.push_back(D->isExceptionVariable());
555   Record.push_back(D->isNRVOVariable());
556   Record.push_back(D->isCXXForRangeDecl());
557   Record.push_back(D->getInit() ? 1 : 0);
558   if (D->getInit())
559     Writer.AddStmt(D->getInit());
560 
561   MemberSpecializationInfo *SpecInfo
562     = D->isStaticDataMember() ? D->getMemberSpecializationInfo() : 0;
563   Record.push_back(SpecInfo != 0);
564   if (SpecInfo) {
565     Writer.AddDeclRef(SpecInfo->getInstantiatedFrom(), Record);
566     Record.push_back(SpecInfo->getTemplateSpecializationKind());
567     Writer.AddSourceLocation(SpecInfo->getPointOfInstantiation(), Record);
568   }
569 
570   Code = serialization::DECL_VAR;
571 }
572 
573 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
574   VisitVarDecl(D);
575   Code = serialization::DECL_IMPLICIT_PARAM;
576 }
577 
578 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
579   VisitVarDecl(D);
580   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
581   Record.push_back(D->isKNRPromoted());
582   Record.push_back(D->hasInheritedDefaultArg());
583   Record.push_back(D->hasUninstantiatedDefaultArg());
584   if (D->hasUninstantiatedDefaultArg())
585     Writer.AddStmt(D->getUninstantiatedDefaultArg());
586   Code = serialization::DECL_PARM_VAR;
587 
588   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
589   // we dynamically check for the properties that we optimize for, but don't
590   // know are true of all PARM_VAR_DECLs.
591   if (!D->getTypeSourceInfo() &&
592       !D->hasAttrs() &&
593       !D->isImplicit() &&
594       !D->isUsed(false) &&
595       D->getAccess() == AS_none &&
596       D->getPCHLevel() == 0 &&
597       D->getStorageClass() == 0 &&
598       !D->hasCXXDirectInitializer() && // Can params have this ever?
599       D->getObjCDeclQualifier() == 0 &&
600       !D->isKNRPromoted() &&
601       !D->hasInheritedDefaultArg() &&
602       D->getInit() == 0 &&
603       !D->hasUninstantiatedDefaultArg())  // No default expr.
604     AbbrevToUse = Writer.getParmVarDeclAbbrev();
605 
606   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
607   // just us assuming it.
608   assert(!D->isInvalidDecl() && "Shouldn't emit invalid decls");
609   assert(!D->isThreadSpecified() && "PARM_VAR_DECL can't be __thread");
610   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
611   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
612   assert(D->getPreviousDeclaration() == 0 && "PARM_VAR_DECL can't be redecl");
613   assert(!D->isStaticDataMember() &&
614          "PARM_VAR_DECL can't be static data member");
615 }
616 
617 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
618   VisitDecl(D);
619   Writer.AddStmt(D->getAsmString());
620   Writer.AddSourceLocation(D->getRParenLoc(), Record);
621   Code = serialization::DECL_FILE_SCOPE_ASM;
622 }
623 
624 void ASTDeclWriter::VisitBlockDecl(BlockDecl *D) {
625   VisitDecl(D);
626   Writer.AddStmt(D->getBody());
627   Writer.AddTypeSourceInfo(D->getSignatureAsWritten(), Record);
628   Record.push_back(D->param_size());
629   for (FunctionDecl::param_iterator P = D->param_begin(), PEnd = D->param_end();
630        P != PEnd; ++P)
631     Writer.AddDeclRef(*P, Record);
632   Record.push_back(D->capturesCXXThis());
633   Record.push_back(D->getNumCaptures());
634   for (BlockDecl::capture_iterator
635          i = D->capture_begin(), e = D->capture_end(); i != e; ++i) {
636     const BlockDecl::Capture &capture = *i;
637     Writer.AddDeclRef(capture.getVariable(), Record);
638 
639     unsigned flags = 0;
640     if (capture.isByRef()) flags |= 1;
641     if (capture.isNested()) flags |= 2;
642     if (capture.hasCopyExpr()) flags |= 4;
643     Record.push_back(flags);
644 
645     if (capture.hasCopyExpr()) Writer.AddStmt(capture.getCopyExpr());
646   }
647 
648   Code = serialization::DECL_BLOCK;
649 }
650 
651 void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
652   VisitDecl(D);
653   Record.push_back(D->getLanguage());
654   Writer.AddSourceLocation(D->getExternLoc(), Record);
655   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
656   Code = serialization::DECL_LINKAGE_SPEC;
657 }
658 
659 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
660   VisitNamedDecl(D);
661   Writer.AddSourceLocation(D->getLocStart(), Record);
662   Code = serialization::DECL_LABEL;
663 }
664 
665 
666 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
667   VisitNamedDecl(D);
668   Record.push_back(D->isInline());
669   Writer.AddSourceLocation(D->getLocStart(), Record);
670   Writer.AddSourceLocation(D->getRBraceLoc(), Record);
671   Writer.AddDeclRef(D->getNextNamespace(), Record);
672 
673   // Only write one reference--original or anonymous
674   Record.push_back(D->isOriginalNamespace());
675   if (D->isOriginalNamespace())
676     Writer.AddDeclRef(D->getAnonymousNamespace(), Record);
677   else
678     Writer.AddDeclRef(D->getOriginalNamespace(), Record);
679   Code = serialization::DECL_NAMESPACE;
680 
681   if (Writer.hasChain() && !D->isOriginalNamespace() &&
682       D->getOriginalNamespace()->getPCHLevel() > 0) {
683     NamespaceDecl *NS = D->getOriginalNamespace();
684     Writer.AddUpdatedDeclContext(NS);
685 
686     // Make sure all visible decls are written. They will be recorded later.
687     NS->lookup(DeclarationName());
688     StoredDeclsMap *Map = static_cast<StoredDeclsMap*>(NS->getLookupPtr());
689     if (Map) {
690       for (StoredDeclsMap::iterator D = Map->begin(), DEnd = Map->end();
691            D != DEnd; ++D) {
692         DeclContext::lookup_result Result = D->second.getLookupResult();
693         while (Result.first != Result.second) {
694           Writer.GetDeclRef(*Result.first);
695           ++Result.first;
696         }
697       }
698     }
699   }
700 }
701 
702 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
703   VisitNamedDecl(D);
704   Writer.AddSourceLocation(D->getNamespaceLoc(), Record);
705   Writer.AddSourceLocation(D->getTargetNameLoc(), Record);
706   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
707   Writer.AddDeclRef(D->getNamespace(), Record);
708   Code = serialization::DECL_NAMESPACE_ALIAS;
709 }
710 
711 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
712   VisitNamedDecl(D);
713   Writer.AddSourceLocation(D->getUsingLocation(), Record);
714   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
715   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
716   Writer.AddDeclRef(D->FirstUsingShadow, Record);
717   Record.push_back(D->isTypeName());
718   Writer.AddDeclRef(Context.getInstantiatedFromUsingDecl(D), Record);
719   Code = serialization::DECL_USING;
720 }
721 
722 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
723   VisitNamedDecl(D);
724   Writer.AddDeclRef(D->getTargetDecl(), Record);
725   Writer.AddDeclRef(D->UsingOrNextShadow, Record);
726   Writer.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D), Record);
727   Code = serialization::DECL_USING_SHADOW;
728 }
729 
730 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
731   VisitNamedDecl(D);
732   Writer.AddSourceLocation(D->getUsingLoc(), Record);
733   Writer.AddSourceLocation(D->getNamespaceKeyLocation(), Record);
734   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
735   Writer.AddDeclRef(D->getNominatedNamespace(), Record);
736   Writer.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()), Record);
737   Code = serialization::DECL_USING_DIRECTIVE;
738 }
739 
740 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
741   VisitValueDecl(D);
742   Writer.AddSourceLocation(D->getUsingLoc(), Record);
743   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
744   Writer.AddDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record);
745   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
746 }
747 
748 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
749                                                UnresolvedUsingTypenameDecl *D) {
750   VisitTypeDecl(D);
751   Writer.AddSourceLocation(D->getTypenameLoc(), Record);
752   Writer.AddNestedNameSpecifierLoc(D->getQualifierLoc(), Record);
753   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
754 }
755 
756 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
757   VisitRecordDecl(D);
758 
759   CXXRecordDecl *DefinitionDecl = 0;
760   if (D->DefinitionData)
761     DefinitionDecl = D->DefinitionData->Definition;
762   Writer.AddDeclRef(DefinitionDecl, Record);
763   if (D == DefinitionDecl)
764     Writer.AddCXXDefinitionData(D, Record);
765 
766   enum {
767     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
768   };
769   if (ClassTemplateDecl *TemplD = D->getDescribedClassTemplate()) {
770     Record.push_back(CXXRecTemplate);
771     Writer.AddDeclRef(TemplD, Record);
772   } else if (MemberSpecializationInfo *MSInfo
773                = D->getMemberSpecializationInfo()) {
774     Record.push_back(CXXRecMemberSpecialization);
775     Writer.AddDeclRef(MSInfo->getInstantiatedFrom(), Record);
776     Record.push_back(MSInfo->getTemplateSpecializationKind());
777     Writer.AddSourceLocation(MSInfo->getPointOfInstantiation(), Record);
778   } else {
779     Record.push_back(CXXRecNotTemplate);
780   }
781 
782   // Store the key function to avoid deserializing every method so we can
783   // compute it.
784   if (D->IsDefinition)
785     Writer.AddDeclRef(Context.getKeyFunction(D), Record);
786 
787   Code = serialization::DECL_CXX_RECORD;
788 }
789 
790 void ASTDeclWriter::VisitCXXMethodDecl(CXXMethodDecl *D) {
791   VisitFunctionDecl(D);
792   Record.push_back(D->size_overridden_methods());
793   for (CXXMethodDecl::method_iterator
794          I = D->begin_overridden_methods(), E = D->end_overridden_methods();
795          I != E; ++I)
796     Writer.AddDeclRef(*I, Record);
797   Code = serialization::DECL_CXX_METHOD;
798 }
799 
800 void ASTDeclWriter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
801   VisitCXXMethodDecl(D);
802 
803   Record.push_back(D->IsExplicitSpecified);
804   Record.push_back(D->ImplicitlyDefined);
805   Writer.AddCXXCtorInitializers(D->CtorInitializers, D->NumCtorInitializers,
806                                 Record);
807 
808   Code = serialization::DECL_CXX_CONSTRUCTOR;
809 }
810 
811 void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
812   VisitCXXMethodDecl(D);
813 
814   Record.push_back(D->ImplicitlyDefined);
815   Writer.AddDeclRef(D->OperatorDelete, Record);
816 
817   Code = serialization::DECL_CXX_DESTRUCTOR;
818 }
819 
820 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
821   VisitCXXMethodDecl(D);
822   Record.push_back(D->IsExplicitSpecified);
823   Code = serialization::DECL_CXX_CONVERSION;
824 }
825 
826 void ASTDeclWriter::VisitAccessSpecDecl(AccessSpecDecl *D) {
827   VisitDecl(D);
828   Writer.AddSourceLocation(D->getColonLoc(), Record);
829   Code = serialization::DECL_ACCESS_SPEC;
830 }
831 
832 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
833   VisitDecl(D);
834   Record.push_back(D->Friend.is<TypeSourceInfo*>());
835   if (D->Friend.is<TypeSourceInfo*>())
836     Writer.AddTypeSourceInfo(D->Friend.get<TypeSourceInfo*>(), Record);
837   else
838     Writer.AddDeclRef(D->Friend.get<NamedDecl*>(), Record);
839   Writer.AddDeclRef(D->getNextFriend(), Record);
840   Record.push_back(D->UnsupportedFriend);
841   Writer.AddSourceLocation(D->FriendLoc, Record);
842   Code = serialization::DECL_FRIEND;
843 }
844 
845 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
846   VisitDecl(D);
847   Record.push_back(D->getNumTemplateParameters());
848   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
849     Writer.AddTemplateParameterList(D->getTemplateParameterList(i), Record);
850   Record.push_back(D->getFriendDecl() != 0);
851   if (D->getFriendDecl())
852     Writer.AddDeclRef(D->getFriendDecl(), Record);
853   else
854     Writer.AddTypeSourceInfo(D->getFriendType(), Record);
855   Writer.AddSourceLocation(D->getFriendLoc(), Record);
856   Code = serialization::DECL_FRIEND_TEMPLATE;
857 }
858 
859 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
860   VisitNamedDecl(D);
861 
862   Writer.AddDeclRef(D->getTemplatedDecl(), Record);
863   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
864 }
865 
866 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
867   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
868   // getCommonPtr() can be used while this is still initializing.
869 
870   Writer.AddDeclRef(D->getPreviousDeclaration(), Record);
871   if (D->getPreviousDeclaration())
872     Writer.AddDeclRef(D->getFirstDeclaration(), Record);
873 
874   if (D->getPreviousDeclaration() == 0) {
875     // This TemplateDecl owns the CommonPtr; write it.
876     assert(D->isCanonicalDecl());
877 
878     Writer.AddDeclRef(D->getInstantiatedFromMemberTemplate(), Record);
879     if (D->getInstantiatedFromMemberTemplate())
880       Record.push_back(D->isMemberSpecialization());
881 
882     Writer.AddDeclRef(D->getCommonPtr()->Latest, Record);
883   } else {
884     RedeclarableTemplateDecl *First = D->getFirstDeclaration();
885     assert(First != D);
886     // If this is a most recent redeclaration that is pointed to by a first decl
887     // in a chained PCH, keep track of the association with the map so we can
888     // update the first decl during AST reading.
889     if (First->getMostRecentDeclaration() == D &&
890         First->getPCHLevel() > D->getPCHLevel()) {
891       assert(Writer.FirstLatestDecls.find(First)==Writer.FirstLatestDecls.end()
892              && "The latest is already set");
893       Writer.FirstLatestDecls[First] = D;
894     }
895   }
896 
897   VisitTemplateDecl(D);
898   Record.push_back(D->getIdentifierNamespace());
899 }
900 
901 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
902   VisitRedeclarableTemplateDecl(D);
903 
904   if (D->getPreviousDeclaration() == 0) {
905     typedef llvm::FoldingSet<ClassTemplateSpecializationDecl> CTSDSetTy;
906     CTSDSetTy &CTSDSet = D->getSpecializations();
907     Record.push_back(CTSDSet.size());
908     for (CTSDSetTy::iterator I=CTSDSet.begin(), E = CTSDSet.end(); I!=E; ++I) {
909       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
910       Writer.AddDeclRef(&*I, Record);
911     }
912 
913     typedef llvm::FoldingSet<ClassTemplatePartialSpecializationDecl> CTPSDSetTy;
914     CTPSDSetTy &CTPSDSet = D->getPartialSpecializations();
915     Record.push_back(CTPSDSet.size());
916     for (CTPSDSetTy::iterator I=CTPSDSet.begin(), E=CTPSDSet.end(); I!=E; ++I) {
917       assert(I->isCanonicalDecl() && "Expected only canonical decls in set");
918       Writer.AddDeclRef(&*I, Record);
919     }
920 
921     // InjectedClassNameType is computed, no need to write it.
922   }
923   Code = serialization::DECL_CLASS_TEMPLATE;
924 }
925 
926 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
927                                            ClassTemplateSpecializationDecl *D) {
928   VisitCXXRecordDecl(D);
929 
930   llvm::PointerUnion<ClassTemplateDecl *,
931                      ClassTemplatePartialSpecializationDecl *> InstFrom
932     = D->getSpecializedTemplateOrPartial();
933   Decl *InstFromD;
934   if (InstFrom.is<ClassTemplateDecl *>()) {
935     InstFromD = InstFrom.get<ClassTemplateDecl *>();
936     Writer.AddDeclRef(InstFromD, Record);
937   } else {
938     InstFromD = InstFrom.get<ClassTemplatePartialSpecializationDecl *>();
939     Writer.AddDeclRef(InstFromD, Record);
940     Writer.AddTemplateArgumentList(&D->getTemplateInstantiationArgs(), Record);
941     InstFromD = cast<ClassTemplatePartialSpecializationDecl>(InstFromD)->
942                     getSpecializedTemplate();
943   }
944 
945   // Explicit info.
946   Writer.AddTypeSourceInfo(D->getTypeAsWritten(), Record);
947   if (D->getTypeAsWritten()) {
948     Writer.AddSourceLocation(D->getExternLoc(), Record);
949     Writer.AddSourceLocation(D->getTemplateKeywordLoc(), Record);
950   }
951 
952   Writer.AddTemplateArgumentList(&D->getTemplateArgs(), Record);
953   Writer.AddSourceLocation(D->getPointOfInstantiation(), Record);
954   Record.push_back(D->getSpecializationKind());
955 
956   if (D->isCanonicalDecl()) {
957     // When reading, we'll add it to the folding set of the following template.
958     Writer.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl(), Record);
959   }
960 
961   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
962 }
963 
964 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
965                                     ClassTemplatePartialSpecializationDecl *D) {
966   VisitClassTemplateSpecializationDecl(D);
967 
968   Writer.AddTemplateParameterList(D->getTemplateParameters(), Record);
969 
970   Record.push_back(D->getNumTemplateArgsAsWritten());
971   for (int i = 0, e = D->getNumTemplateArgsAsWritten(); i != e; ++i)
972     Writer.AddTemplateArgumentLoc(D->getTemplateArgsAsWritten()[i], Record);
973 
974   Record.push_back(D->getSequenceNumber());
975 
976   // These are read/set from/to the first declaration.
977   if (D->getPreviousDeclaration() == 0) {
978     Writer.AddDeclRef(D->getInstantiatedFromMember(), Record);
979     Record.push_back(D->isMemberSpecialization());
980   }
981 
982   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
983 }
984 
985 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
986   VisitRedeclarableTemplateDecl(D);
987 
988   if (D->getPreviousDeclaration() == 0) {
989     // This FunctionTemplateDecl owns the CommonPtr; write it.
990 
991     // Write the function specialization declarations.
992     Record.push_back(D->getSpecializations().size());
993     for (llvm::FoldingSet<FunctionTemplateSpecializationInfo>::iterator
994            I = D->getSpecializations().begin(),
995            E = D->getSpecializations().end()   ; I != E; ++I) {
996       assert(I->Function->isCanonicalDecl() &&
997              "Expected only canonical decls in set");
998       Writer.AddDeclRef(I->Function, Record);
999     }
1000   }
1001   Code = serialization::DECL_FUNCTION_TEMPLATE;
1002 }
1003 
1004 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1005   VisitTypeDecl(D);
1006 
1007   Record.push_back(D->wasDeclaredWithTypename());
1008   Record.push_back(D->isParameterPack());
1009   Record.push_back(D->defaultArgumentWasInherited());
1010   Writer.AddTypeSourceInfo(D->getDefaultArgumentInfo(), Record);
1011 
1012   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1013 }
1014 
1015 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1016   // For an expanded parameter pack, record the number of expansion types here
1017   // so that it's easier for
1018   if (D->isExpandedParameterPack())
1019     Record.push_back(D->getNumExpansionTypes());
1020 
1021   VisitDeclaratorDecl(D);
1022   // TemplateParmPosition.
1023   Record.push_back(D->getDepth());
1024   Record.push_back(D->getPosition());
1025 
1026   if (D->isExpandedParameterPack()) {
1027     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1028       Writer.AddTypeRef(D->getExpansionType(I), Record);
1029       Writer.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I), Record);
1030     }
1031 
1032     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1033   } else {
1034     // Rest of NonTypeTemplateParmDecl.
1035     Record.push_back(D->isParameterPack());
1036     Record.push_back(D->getDefaultArgument() != 0);
1037     if (D->getDefaultArgument()) {
1038       Writer.AddStmt(D->getDefaultArgument());
1039       Record.push_back(D->defaultArgumentWasInherited());
1040     }
1041     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1042   }
1043 }
1044 
1045 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1046   VisitTemplateDecl(D);
1047   // TemplateParmPosition.
1048   Record.push_back(D->getDepth());
1049   Record.push_back(D->getPosition());
1050   // Rest of TemplateTemplateParmDecl.
1051   Writer.AddTemplateArgumentLoc(D->getDefaultArgument(), Record);
1052   Record.push_back(D->defaultArgumentWasInherited());
1053   Record.push_back(D->isParameterPack());
1054   Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1055 }
1056 
1057 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1058   VisitDecl(D);
1059   Writer.AddStmt(D->getAssertExpr());
1060   Writer.AddStmt(D->getMessage());
1061   Writer.AddSourceLocation(D->getRParenLoc(), Record);
1062   Code = serialization::DECL_STATIC_ASSERT;
1063 }
1064 
1065 /// \brief Emit the DeclContext part of a declaration context decl.
1066 ///
1067 /// \param LexicalOffset the offset at which the DECL_CONTEXT_LEXICAL
1068 /// block for this declaration context is stored. May be 0 to indicate
1069 /// that there are no declarations stored within this context.
1070 ///
1071 /// \param VisibleOffset the offset at which the DECL_CONTEXT_VISIBLE
1072 /// block for this declaration context is stored. May be 0 to indicate
1073 /// that there are no declarations visible from this context. Note
1074 /// that this value will not be emitted for non-primary declaration
1075 /// contexts.
1076 void ASTDeclWriter::VisitDeclContext(DeclContext *DC, uint64_t LexicalOffset,
1077                                      uint64_t VisibleOffset) {
1078   Record.push_back(LexicalOffset);
1079   Record.push_back(VisibleOffset);
1080 }
1081 
1082 template <typename T>
1083 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1084   enum { NoRedeclaration = 0, PointsToPrevious, PointsToLatest };
1085   if (D->RedeclLink.getNext() == D) {
1086     Record.push_back(NoRedeclaration);
1087   } else {
1088     if (D->RedeclLink.NextIsPrevious()) {
1089       Record.push_back(PointsToPrevious);
1090       Writer.AddDeclRef(D->getPreviousDeclaration(), Record);
1091       Writer.AddDeclRef(D->getFirstDeclaration(), Record);
1092     } else {
1093       Record.push_back(PointsToLatest);
1094       Writer.AddDeclRef(D->RedeclLink.getPointer(), Record);
1095     }
1096   }
1097 
1098   T *First = D->getFirstDeclaration();
1099   T *ThisDecl = static_cast<T*>(D);
1100   // If this is a most recent redeclaration that is pointed to by a first decl
1101   // in a chained PCH, keep track of the association with the map so we can
1102   // update the first decl during AST reading.
1103   if (ThisDecl != First && First->getMostRecentDeclaration() == ThisDecl &&
1104       First->getPCHLevel() > ThisDecl->getPCHLevel()) {
1105     assert(Writer.FirstLatestDecls.find(First) == Writer.FirstLatestDecls.end()
1106            && "The latest is already set");
1107     Writer.FirstLatestDecls[First] = ThisDecl;
1108   }
1109 }
1110 
1111 //===----------------------------------------------------------------------===//
1112 // ASTWriter Implementation
1113 //===----------------------------------------------------------------------===//
1114 
1115 void ASTWriter::WriteDeclsBlockAbbrevs() {
1116   using namespace llvm;
1117   // Abbreviation for DECL_PARM_VAR.
1118   BitCodeAbbrev *Abv = new BitCodeAbbrev();
1119   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1120 
1121   // Decl
1122   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1123   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LexicalDeclContext
1124   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
1125   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl (!?)
1126   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1127   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1128   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1129   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1130   Abv->Add(BitCodeAbbrevOp(0));                       // PCH level
1131 
1132   // NamedDecl
1133   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1134   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1135   // ValueDecl
1136   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1137   // DeclaratorDecl
1138   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1139   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1140   Abv->Add(BitCodeAbbrevOp(serialization::PREDEF_TYPE_NULL_ID)); // InfoType
1141   // VarDecl
1142   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1143   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClass
1144   Abv->Add(BitCodeAbbrevOp(0));                       // StorageClassAsWritten
1145   Abv->Add(BitCodeAbbrevOp(0));                       // isThreadSpecified
1146   Abv->Add(BitCodeAbbrevOp(0));                       // hasCXXDirectInitializer
1147   Abv->Add(BitCodeAbbrevOp(0));                       // isExceptionVariable
1148   Abv->Add(BitCodeAbbrevOp(0));                       // isNRVOVariable
1149   Abv->Add(BitCodeAbbrevOp(0));                       // isCXXForRangeDecl
1150   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
1151   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
1152   // ParmVarDecl
1153   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
1154   Abv->Add(BitCodeAbbrevOp(0));                       // KNRPromoted
1155   Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
1156   Abv->Add(BitCodeAbbrevOp(0));                   // HasUninstantiatedDefaultArg
1157 
1158   ParmVarDeclAbbrev = Stream.EmitAbbrev(Abv);
1159 
1160   Abv = new BitCodeAbbrev();
1161   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
1162   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1163   DeclContextLexicalAbbrev = Stream.EmitAbbrev(Abv);
1164 
1165   Abv = new BitCodeAbbrev();
1166   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
1167   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1168   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1169   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(Abv);
1170 }
1171 
1172 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
1173 /// consumers of the AST.
1174 ///
1175 /// Such decls will always be deserialized from the AST file, so we would like
1176 /// this to be as restrictive as possible. Currently the predicate is driven by
1177 /// code generation requirements, if other clients have a different notion of
1178 /// what is "required" then we may have to consider an alternate scheme where
1179 /// clients can iterate over the top-level decls and get information on them,
1180 /// without necessary deserializing them. We could explicitly require such
1181 /// clients to use a separate API call to "realize" the decl. This should be
1182 /// relatively painless since they would presumably only do it for top-level
1183 /// decls.
1184 static bool isRequiredDecl(const Decl *D, ASTContext &Context) {
1185   // File scoped assembly or obj-c implementation must be seen.
1186   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplementationDecl>(D))
1187     return true;
1188 
1189   return Context.DeclMustBeEmitted(D);
1190 }
1191 
1192 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
1193   // Switch case IDs are per Decl.
1194   ClearSwitchCaseIDs();
1195 
1196   RecordData Record;
1197   ASTDeclWriter W(*this, Context, Record);
1198 
1199   // If this declaration is also a DeclContext, write blocks for the
1200   // declarations that lexically stored inside its context and those
1201   // declarations that are visible from its context. These blocks
1202   // are written before the declaration itself so that we can put
1203   // their offsets into the record for the declaration.
1204   uint64_t LexicalOffset = 0;
1205   uint64_t VisibleOffset = 0;
1206   DeclContext *DC = dyn_cast<DeclContext>(D);
1207   if (DC) {
1208     LexicalOffset = WriteDeclContextLexicalBlock(Context, DC);
1209     VisibleOffset = WriteDeclContextVisibleBlock(Context, DC);
1210   }
1211 
1212   // Determine the ID for this declaration
1213   serialization::DeclID &IDR = DeclIDs[D];
1214   if (IDR == 0)
1215     IDR = NextDeclID++;
1216   serialization::DeclID ID = IDR;
1217 
1218   if (ID < FirstDeclID) {
1219     // We're replacing a decl in a previous file.
1220     ReplacedDecls.push_back(std::make_pair(ID, Stream.GetCurrentBitNo()));
1221   } else {
1222     unsigned Index = ID - FirstDeclID;
1223 
1224     // Record the offset for this declaration
1225     if (DeclOffsets.size() == Index)
1226       DeclOffsets.push_back(Stream.GetCurrentBitNo());
1227     else if (DeclOffsets.size() < Index) {
1228       DeclOffsets.resize(Index+1);
1229       DeclOffsets[Index] = Stream.GetCurrentBitNo();
1230     }
1231   }
1232 
1233   // Build and emit a record for this declaration
1234   Record.clear();
1235   W.Code = (serialization::DeclCode)0;
1236   W.AbbrevToUse = 0;
1237   W.Visit(D);
1238   if (DC) W.VisitDeclContext(DC, LexicalOffset, VisibleOffset);
1239 
1240   if (!W.Code)
1241     llvm::report_fatal_error(llvm::StringRef("unexpected declaration kind '") +
1242                             D->getDeclKindName() + "'");
1243   Stream.EmitRecord(W.Code, Record, W.AbbrevToUse);
1244 
1245   // Flush any expressions that were written as part of this declaration.
1246   FlushStmts();
1247 
1248   // Flush C++ base specifiers, if there are any.
1249   FlushCXXBaseSpecifiers();
1250 
1251   // Note "external" declarations so that we can add them to a record in the
1252   // AST file later.
1253   //
1254   // FIXME: This should be renamed, the predicate is much more complicated.
1255   if (isRequiredDecl(D, Context))
1256     ExternalDefinitions.push_back(ID);
1257 }
1258