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