lib/Serialization/ASTWriterDecl.cpp

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