contrib/llvm/tools/clang/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 "ASTCommon.h"
  15 #include "clang/AST/DeclCXX.h"
  16 #include "clang/AST/DeclContextInternals.h"
  17 #include "clang/AST/DeclTemplate.h"
  18 #include "clang/AST/DeclVisitor.h"
  19 #include "clang/AST/Expr.h"
  20 #include "clang/Basic/SourceManager.h"
  21 #include "clang/Serialization/ASTReader.h"
  22 #include "clang/Serialization/ASTWriter.h"
  23 #include "llvm/Bitcode/BitstreamWriter.h"
  24 #include "llvm/Support/ErrorHandling.h"
  25 using namespace clang;
  26 using namespace serialization;
  27
  28 //===----------------------------------------------------------------------===//
  29 // Declaration serialization
  30 //===----------------------------------------------------------------------===//
  31
  32 namespace clang {
  33   class ASTDeclWriter : public DeclVisitor<ASTDeclWriter, void> {
  34     ASTWriter &Writer;
  35     ASTContext &Context;
  36     ASTRecordWriter Record;
  37
  38     serialization::DeclCode Code;
  39     unsigned AbbrevToUse;
  40
  41   public:
  42     ASTDeclWriter(ASTWriter &Writer, ASTContext &Context,
  43                   ASTWriter::RecordDataImpl &Record)
  44         : Writer(Writer), Context(Context), Record(Writer, Record),
  45           Code((serialization::DeclCode)0), AbbrevToUse(0) {}
  46
  47     uint64_t Emit(Decl *D) {
  48       if (!Code)
  49         llvm::report_fatal_error(StringRef("unexpected declaration kind '") +
  50             D->getDeclKindName() + "'");
  51       return Record.Emit(Code, AbbrevToUse);
  52     }
  53
  54     void Visit(Decl *D);
  55
  56     void VisitDecl(Decl *D);
  57     void VisitPragmaCommentDecl(PragmaCommentDecl *D);
  58     void VisitPragmaDetectMismatchDecl(PragmaDetectMismatchDecl *D);
  59     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
  60     void VisitNamedDecl(NamedDecl *D);
  61     void VisitLabelDecl(LabelDecl *LD);
  62     void VisitNamespaceDecl(NamespaceDecl *D);
  63     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
  64     void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
  65     void VisitTypeDecl(TypeDecl *D);
  66     void VisitTypedefNameDecl(TypedefNameDecl *D);
  67     void VisitTypedefDecl(TypedefDecl *D);
  68     void VisitTypeAliasDecl(TypeAliasDecl *D);
  69     void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
  70     void VisitTagDecl(TagDecl *D);
  71     void VisitEnumDecl(EnumDecl *D);
  72     void VisitRecordDecl(RecordDecl *D);
  73     void VisitCXXRecordDecl(CXXRecordDecl *D);
  74     void VisitClassTemplateSpecializationDecl(
  75                                             ClassTemplateSpecializationDecl *D);
  76     void VisitClassTemplatePartialSpecializationDecl(
  77                                      ClassTemplatePartialSpecializationDecl *D);
  78     void VisitVarTemplateSpecializationDecl(VarTemplateSpecializationDecl *D);
  79     void VisitVarTemplatePartialSpecializationDecl(
  80         VarTemplatePartialSpecializationDecl *D);
  81     void VisitClassScopeFunctionSpecializationDecl(
  82                                        ClassScopeFunctionSpecializationDecl *D);
  83     void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
  84     void VisitValueDecl(ValueDecl *D);
  85     void VisitEnumConstantDecl(EnumConstantDecl *D);
  86     void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
  87     void VisitDeclaratorDecl(DeclaratorDecl *D);
  88     void VisitFunctionDecl(FunctionDecl *D);
  89     void VisitCXXDeductionGuideDecl(CXXDeductionGuideDecl *D);
  90     void VisitCXXMethodDecl(CXXMethodDecl *D);
  91     void VisitCXXConstructorDecl(CXXConstructorDecl *D);
  92     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
  93     void VisitCXXConversionDecl(CXXConversionDecl *D);
  94     void VisitFieldDecl(FieldDecl *D);
  95     void VisitMSPropertyDecl(MSPropertyDecl *D);
  96     void VisitIndirectFieldDecl(IndirectFieldDecl *D);
  97     void VisitVarDecl(VarDecl *D);
  98     void VisitImplicitParamDecl(ImplicitParamDecl *D);
  99     void VisitParmVarDecl(ParmVarDecl *D);
 100     void VisitDecompositionDecl(DecompositionDecl *D);
 101     void VisitBindingDecl(BindingDecl *D);
 102     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
 103     void VisitTemplateDecl(TemplateDecl *D);
 104     void VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
 105     void VisitClassTemplateDecl(ClassTemplateDecl *D);
 106     void VisitVarTemplateDecl(VarTemplateDecl *D);
 107     void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
 108     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
 109     void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
 110     void VisitUsingDecl(UsingDecl *D);
 111     void VisitUsingPackDecl(UsingPackDecl *D);
 112     void VisitUsingShadowDecl(UsingShadowDecl *D);
 113     void VisitConstructorUsingShadowDecl(ConstructorUsingShadowDecl *D);
 114     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
 115     void VisitExportDecl(ExportDecl *D);
 116     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
 117     void VisitImportDecl(ImportDecl *D);
 118     void VisitAccessSpecDecl(AccessSpecDecl *D);
 119     void VisitFriendDecl(FriendDecl *D);
 120     void VisitFriendTemplateDecl(FriendTemplateDecl *D);
 121     void VisitStaticAssertDecl(StaticAssertDecl *D);
 122     void VisitBlockDecl(BlockDecl *D);
 123     void VisitCapturedDecl(CapturedDecl *D);
 124     void VisitEmptyDecl(EmptyDecl *D);
 125
 126     void VisitDeclContext(DeclContext *DC);
 127     template <typename T> void VisitRedeclarable(Redeclarable<T> *D);
 128
 129
 130     // FIXME: Put in the same order is DeclNodes.td?
 131     void VisitObjCMethodDecl(ObjCMethodDecl *D);
 132     void VisitObjCTypeParamDecl(ObjCTypeParamDecl *D);
 133     void VisitObjCContainerDecl(ObjCContainerDecl *D);
 134     void VisitObjCInterfaceDecl(ObjCInterfaceDecl *D);
 135     void VisitObjCIvarDecl(ObjCIvarDecl *D);
 136     void VisitObjCProtocolDecl(ObjCProtocolDecl *D);
 137     void VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D);
 138     void VisitObjCCategoryDecl(ObjCCategoryDecl *D);
 139     void VisitObjCImplDecl(ObjCImplDecl *D);
 140     void VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D);
 141     void VisitObjCImplementationDecl(ObjCImplementationDecl *D);
 142     void VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D);
 143     void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
 144     void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
 145     void VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D);
 146     void VisitOMPDeclareReductionDecl(OMPDeclareReductionDecl *D);
 147     void VisitOMPCapturedExprDecl(OMPCapturedExprDecl *D);
 148
 149     /// Add an Objective-C type parameter list to the given record.
 150     void AddObjCTypeParamList(ObjCTypeParamList *typeParams) {
 151       // Empty type parameter list.
 152       if (!typeParams) {
 153         Record.push_back(0);
 154         return;
 155       }
 156
 157       Record.push_back(typeParams->size());
 158       for (auto typeParam : *typeParams) {
 159         Record.AddDeclRef(typeParam);
 160       }
 161       Record.AddSourceLocation(typeParams->getLAngleLoc());
 162       Record.AddSourceLocation(typeParams->getRAngleLoc());
 163     }
 164
 165     /// Add to the record the first declaration from each module file that
 166     /// provides a declaration of D. The intent is to provide a sufficient
 167     /// set such that reloading this set will load all current redeclarations.
 168     void AddFirstDeclFromEachModule(const Decl *D, bool IncludeLocal) {
 169       llvm::MapVector<ModuleFile*, const Decl*> Firsts;
 170       // FIXME: We can skip entries that we know are implied by others.
 171       for (const Decl *R = D->getMostRecentDecl(); R; R = R->getPreviousDecl()) {
 172         if (R->isFromASTFile())
 173           Firsts[Writer.Chain->getOwningModuleFile(R)] = R;
 174         else if (IncludeLocal)
 175           Firsts[nullptr] = R;
 176       }
 177       for (const auto &F : Firsts)
 178         Record.AddDeclRef(F.second);
 179     }
 180
 181     /// Get the specialization decl from an entry in the specialization list.
 182     template <typename EntryType>
 183     typename RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::DeclType *
 184     getSpecializationDecl(EntryType &T) {
 185       return RedeclarableTemplateDecl::SpecEntryTraits<EntryType>::getDecl(&T);
 186     }
 187
 188     /// Get the list of partial specializations from a template's common ptr.
 189     template<typename T>
 190     decltype(T::PartialSpecializations) &getPartialSpecializations(T *Common) {
 191       return Common->PartialSpecializations;
 192     }
 193     ArrayRef<Decl> getPartialSpecializations(FunctionTemplateDecl::Common *) {
 194       return None;
 195     }
 196
 197     template<typename DeclTy>
 198     void AddTemplateSpecializations(DeclTy *D) {
 199       auto *Common = D->getCommonPtr();
 200
 201       // If we have any lazy specializations, and the external AST source is
 202       // our chained AST reader, we can just write out the DeclIDs. Otherwise,
 203       // we need to resolve them to actual declarations.
 204       if (Writer.Chain != Writer.Context->getExternalSource() &&
 205           Common->LazySpecializations) {
 206         D->LoadLazySpecializations();
 207         assert(!Common->LazySpecializations);
 208       }
 209
 210       ArrayRef<DeclID> LazySpecializations;
 211       if (auto *LS = Common->LazySpecializations)
 212         LazySpecializations = llvm::makeArrayRef(LS + 1, LS[0]);
 213
 214       // Add a slot to the record for the number of specializations.
 215       unsigned I = Record.size();
 216       Record.push_back(0);
 217
 218       // AddFirstDeclFromEachModule might trigger deserialization, invalidating
 219       // *Specializations iterators.
 220       llvm::SmallVector<const Decl*, 16> Specs;
 221       for (auto &Entry : Common->Specializations)
 222         Specs.push_back(getSpecializationDecl(Entry));
 223       for (auto &Entry : getPartialSpecializations(Common))
 224         Specs.push_back(getSpecializationDecl(Entry));
 225
 226       for (auto *D : Specs) {
 227         assert(D->isCanonicalDecl() && "non-canonical decl in set");
 228         AddFirstDeclFromEachModule(D, /*IncludeLocal*/true);
 229       }
 230       Record.append(LazySpecializations.begin(), LazySpecializations.end());
 231
 232       // Update the size entry we added earlier.
 233       Record[I] = Record.size() - I - 1;
 234     }
 235
 236     /// Ensure that this template specialization is associated with the specified
 237     /// template on reload.
 238     void RegisterTemplateSpecialization(const Decl *Template,
 239                                         const Decl *Specialization) {
 240       Template = Template->getCanonicalDecl();
 241
 242       // If the canonical template is local, we'll write out this specialization
 243       // when we emit it.
 244       // FIXME: We can do the same thing if there is any local declaration of
 245       // the template, to avoid emitting an update record.
 246       if (!Template->isFromASTFile())
 247         return;
 248
 249       // We only need to associate the first local declaration of the
 250       // specialization. The other declarations will get pulled in by it.
 251       if (Writer.getFirstLocalDecl(Specialization) != Specialization)
 252         return;
 253
 254       Writer.DeclUpdates[Template].push_back(ASTWriter::DeclUpdate(
 255           UPD_CXX_ADDED_TEMPLATE_SPECIALIZATION, Specialization));
 256     }
 257   };
 258 }
 259
 260 void ASTDeclWriter::Visit(Decl *D) {
 261   DeclVisitor<ASTDeclWriter>::Visit(D);
 262
 263   // Source locations require array (variable-length) abbreviations.  The
 264   // abbreviation infrastructure requires that arrays are encoded last, so
 265   // we handle it here in the case of those classes derived from DeclaratorDecl
 266   if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)) {
 267     Record.AddTypeSourceInfo(DD->getTypeSourceInfo());
 268   }
 269
 270   // Handle FunctionDecl's body here and write it after all other Stmts/Exprs
 271   // have been written. We want it last because we will not read it back when
 272   // retrieving it from the AST, we'll just lazily set the offset.
 273   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
 274     Record.push_back(FD->doesThisDeclarationHaveABody());
 275     if (FD->doesThisDeclarationHaveABody())
 276       Record.AddFunctionDefinition(FD);
 277   }
 278
 279   // If this declaration is also a DeclContext, write blocks for the
 280   // declarations that lexically stored inside its context and those
 281   // declarations that are visible from its context.
 282   if (DeclContext *DC = dyn_cast<DeclContext>(D))
 283     VisitDeclContext(DC);
 284 }
 285
 286 void ASTDeclWriter::VisitDecl(Decl *D) {
 287   Record.AddDeclRef(cast_or_null<Decl>(D->getDeclContext()));
 288   if (D->getDeclContext() != D->getLexicalDeclContext())
 289     Record.AddDeclRef(cast_or_null<Decl>(D->getLexicalDeclContext()));
 290   else
 291     Record.push_back(0);
 292   Record.push_back(D->isInvalidDecl());
 293   Record.push_back(D->hasAttrs());
 294   if (D->hasAttrs())
 295     Record.AddAttributes(D->getAttrs());
 296   Record.push_back(D->isImplicit());
 297   Record.push_back(D->isUsed(false));
 298   Record.push_back(D->isReferenced());
 299   Record.push_back(D->isTopLevelDeclInObjCContainer());
 300   Record.push_back(D->getAccess());
 301   Record.push_back(D->isModulePrivate());
 302   Record.push_back(Writer.getSubmoduleID(D->getOwningModule()));
 303
 304   // If this declaration injected a name into a context different from its
 305   // lexical context, and that context is an imported namespace, we need to
 306   // update its visible declarations to include this name.
 307   //
 308   // This happens when we instantiate a class with a friend declaration or a
 309   // function with a local extern declaration, for instance.
 310   //
 311   // FIXME: Can we handle this in AddedVisibleDecl instead?
 312   if (D->isOutOfLine()) {
 313     auto *DC = D->getDeclContext();
 314     while (auto *NS = dyn_cast<NamespaceDecl>(DC->getRedeclContext())) {
 315       if (!NS->isFromASTFile())
 316         break;
 317       Writer.UpdatedDeclContexts.insert(NS->getPrimaryContext());
 318       if (!NS->isInlineNamespace())
 319         break;
 320       DC = NS->getParent();
 321     }
 322   }
 323 }
 324
 325 void ASTDeclWriter::VisitPragmaCommentDecl(PragmaCommentDecl *D) {
 326   StringRef Arg = D->getArg();
 327   Record.push_back(Arg.size());
 328   VisitDecl(D);
 329   Record.AddSourceLocation(D->getLocStart());
 330   Record.push_back(D->getCommentKind());
 331   Record.AddString(Arg);
 332   Code = serialization::DECL_PRAGMA_COMMENT;
 333 }
 334
 335 void ASTDeclWriter::VisitPragmaDetectMismatchDecl(
 336     PragmaDetectMismatchDecl *D) {
 337   StringRef Name = D->getName();
 338   StringRef Value = D->getValue();
 339   Record.push_back(Name.size() + 1 + Value.size());
 340   VisitDecl(D);
 341   Record.AddSourceLocation(D->getLocStart());
 342   Record.AddString(Name);
 343   Record.AddString(Value);
 344   Code = serialization::DECL_PRAGMA_DETECT_MISMATCH;
 345 }
 346
 347 void ASTDeclWriter::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
 348   llvm_unreachable("Translation units aren't directly serialized");
 349 }
 350
 351 void ASTDeclWriter::VisitNamedDecl(NamedDecl *D) {
 352   VisitDecl(D);
 353   Record.AddDeclarationName(D->getDeclName());
 354   Record.push_back(needsAnonymousDeclarationNumber(D)
 355                        ? Writer.getAnonymousDeclarationNumber(D)
 356                        : 0);
 357 }
 358
 359 void ASTDeclWriter::VisitTypeDecl(TypeDecl *D) {
 360   VisitNamedDecl(D);
 361   Record.AddSourceLocation(D->getLocStart());
 362   Record.AddTypeRef(QualType(D->getTypeForDecl(), 0));
 363 }
 364
 365 void ASTDeclWriter::VisitTypedefNameDecl(TypedefNameDecl *D) {
 366   VisitRedeclarable(D);
 367   VisitTypeDecl(D);
 368   Record.AddTypeSourceInfo(D->getTypeSourceInfo());
 369   Record.push_back(D->isModed());
 370   if (D->isModed())
 371     Record.AddTypeRef(D->getUnderlyingType());
 372   Record.AddDeclRef(D->getAnonDeclWithTypedefName(false));
 373 }
 374
 375 void ASTDeclWriter::VisitTypedefDecl(TypedefDecl *D) {
 376   VisitTypedefNameDecl(D);
 377   if (D->getDeclContext() == D->getLexicalDeclContext() &&
 378       !D->hasAttrs() &&
 379       !D->isImplicit() &&
 380       D->getFirstDecl() == D->getMostRecentDecl() &&
 381       !D->isInvalidDecl() &&
 382       !D->isTopLevelDeclInObjCContainer() &&
 383       !D->isModulePrivate() &&
 384       !needsAnonymousDeclarationNumber(D) &&
 385       D->getDeclName().getNameKind() == DeclarationName::Identifier)
 386     AbbrevToUse = Writer.getDeclTypedefAbbrev();
 387
 388   Code = serialization::DECL_TYPEDEF;
 389 }
 390
 391 void ASTDeclWriter::VisitTypeAliasDecl(TypeAliasDecl *D) {
 392   VisitTypedefNameDecl(D);
 393   Record.AddDeclRef(D->getDescribedAliasTemplate());
 394   Code = serialization::DECL_TYPEALIAS;
 395 }
 396
 397 void ASTDeclWriter::VisitTagDecl(TagDecl *D) {
 398   VisitRedeclarable(D);
 399   VisitTypeDecl(D);
 400   Record.push_back(D->getIdentifierNamespace());
 401   Record.push_back((unsigned)D->getTagKind()); // FIXME: stable encoding
 402   if (!isa<CXXRecordDecl>(D))
 403     Record.push_back(D->isCompleteDefinition());
 404   Record.push_back(D->isEmbeddedInDeclarator());
 405   Record.push_back(D->isFreeStanding());
 406   Record.push_back(D->isCompleteDefinitionRequired());
 407   Record.AddSourceRange(D->getBraceRange());
 408
 409   if (D->hasExtInfo()) {
 410     Record.push_back(1);
 411     Record.AddQualifierInfo(*D->getExtInfo());
 412   } else if (auto *TD = D->getTypedefNameForAnonDecl()) {
 413     Record.push_back(2);
 414     Record.AddDeclRef(TD);
 415     Record.AddIdentifierRef(TD->getDeclName().getAsIdentifierInfo());
 416   } else {
 417     Record.push_back(0);
 418   }
 419 }
 420
 421 void ASTDeclWriter::VisitEnumDecl(EnumDecl *D) {
 422   VisitTagDecl(D);
 423   Record.AddTypeSourceInfo(D->getIntegerTypeSourceInfo());
 424   if (!D->getIntegerTypeSourceInfo())
 425     Record.AddTypeRef(D->getIntegerType());
 426   Record.AddTypeRef(D->getPromotionType());
 427   Record.push_back(D->getNumPositiveBits());
 428   Record.push_back(D->getNumNegativeBits());
 429   Record.push_back(D->isScoped());
 430   Record.push_back(D->isScopedUsingClassTag());
 431   Record.push_back(D->isFixed());
 432   if (MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo()) {
 433     Record.AddDeclRef(MemberInfo->getInstantiatedFrom());
 434     Record.push_back(MemberInfo->getTemplateSpecializationKind());
 435     Record.AddSourceLocation(MemberInfo->getPointOfInstantiation());
 436   } else {
 437     Record.AddDeclRef(nullptr);
 438   }
 439
 440   if (D->getDeclContext() == D->getLexicalDeclContext() &&
 441       !D->hasAttrs() &&
 442       !D->isImplicit() &&
 443       !D->isUsed(false) &&
 444       !D->hasExtInfo() &&
 445       !D->getTypedefNameForAnonDecl() &&
 446       D->getFirstDecl() == D->getMostRecentDecl() &&
 447       !D->isInvalidDecl() &&
 448       !D->isReferenced() &&
 449       !D->isTopLevelDeclInObjCContainer() &&
 450       D->getAccess() == AS_none &&
 451       !D->isModulePrivate() &&
 452       !CXXRecordDecl::classofKind(D->getKind()) &&
 453       !D->getIntegerTypeSourceInfo() &&
 454       !D->getMemberSpecializationInfo() &&
 455       !needsAnonymousDeclarationNumber(D) &&
 456       D->getDeclName().getNameKind() == DeclarationName::Identifier)
 457     AbbrevToUse = Writer.getDeclEnumAbbrev();
 458
 459   Code = serialization::DECL_ENUM;
 460 }
 461
 462 void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
 463   VisitTagDecl(D);
 464   Record.push_back(D->hasFlexibleArrayMember());
 465   Record.push_back(D->isAnonymousStructOrUnion());
 466   Record.push_back(D->hasObjectMember());
 467   Record.push_back(D->hasVolatileMember());
 468
 469   if (D->getDeclContext() == D->getLexicalDeclContext() &&
 470       !D->hasAttrs() &&
 471       !D->isImplicit() &&
 472       !D->isUsed(false) &&
 473       !D->hasExtInfo() &&
 474       !D->getTypedefNameForAnonDecl() &&
 475       D->getFirstDecl() == D->getMostRecentDecl() &&
 476       !D->isInvalidDecl() &&
 477       !D->isReferenced() &&
 478       !D->isTopLevelDeclInObjCContainer() &&
 479       D->getAccess() == AS_none &&
 480       !D->isModulePrivate() &&
 481       !CXXRecordDecl::classofKind(D->getKind()) &&
 482       !needsAnonymousDeclarationNumber(D) &&
 483       D->getDeclName().getNameKind() == DeclarationName::Identifier)
 484     AbbrevToUse = Writer.getDeclRecordAbbrev();
 485
 486   Code = serialization::DECL_RECORD;
 487 }
 488
 489 void ASTDeclWriter::VisitValueDecl(ValueDecl *D) {
 490   VisitNamedDecl(D);
 491   Record.AddTypeRef(D->getType());
 492 }
 493
 494 void ASTDeclWriter::VisitEnumConstantDecl(EnumConstantDecl *D) {
 495   VisitValueDecl(D);
 496   Record.push_back(D->getInitExpr()? 1 : 0);
 497   if (D->getInitExpr())
 498     Record.AddStmt(D->getInitExpr());
 499   Record.AddAPSInt(D->getInitVal());
 500
 501   Code = serialization::DECL_ENUM_CONSTANT;
 502 }
 503
 504 void ASTDeclWriter::VisitDeclaratorDecl(DeclaratorDecl *D) {
 505   VisitValueDecl(D);
 506   Record.AddSourceLocation(D->getInnerLocStart());
 507   Record.push_back(D->hasExtInfo());
 508   if (D->hasExtInfo())
 509     Record.AddQualifierInfo(*D->getExtInfo());
 510 }
 511
 512 void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
 513   VisitRedeclarable(D);
 514   VisitDeclaratorDecl(D);
 515   Record.AddDeclarationNameLoc(D->DNLoc, D->getDeclName());
 516   Record.push_back(D->getIdentifierNamespace());
 517
 518   // FunctionDecl's body is handled last at ASTWriterDecl::Visit,
 519   // after everything else is written.
 520
 521   Record.push_back((int)D->SClass); // FIXME: stable encoding
 522   Record.push_back(D->IsInline);
 523   Record.push_back(D->IsInlineSpecified);
 524   Record.push_back(D->IsExplicitSpecified);
 525   Record.push_back(D->IsVirtualAsWritten);
 526   Record.push_back(D->IsPure);
 527   Record.push_back(D->HasInheritedPrototype);
 528   Record.push_back(D->HasWrittenPrototype);
 529   Record.push_back(D->IsDeleted);
 530   Record.push_back(D->IsTrivial);
 531   Record.push_back(D->IsDefaulted);
 532   Record.push_back(D->IsExplicitlyDefaulted);
 533   Record.push_back(D->HasImplicitReturnZero);
 534   Record.push_back(D->IsConstexpr);
 535   Record.push_back(D->UsesSEHTry);
 536   Record.push_back(D->HasSkippedBody);
 537   Record.push_back(D->IsLateTemplateParsed);
 538   Record.push_back(D->getLinkageInternal());
 539   Record.AddSourceLocation(D->getLocEnd());
 540
 541   Record.push_back(D->getTemplatedKind());
 542   switch (D->getTemplatedKind()) {
 543   case FunctionDecl::TK_NonTemplate:
 544     break;
 545   case FunctionDecl::TK_FunctionTemplate:
 546     Record.AddDeclRef(D->getDescribedFunctionTemplate());
 547     break;
 548   case FunctionDecl::TK_MemberSpecialization: {
 549     MemberSpecializationInfo *MemberInfo = D->getMemberSpecializationInfo();
 550     Record.AddDeclRef(MemberInfo->getInstantiatedFrom());
 551     Record.push_back(MemberInfo->getTemplateSpecializationKind());
 552     Record.AddSourceLocation(MemberInfo->getPointOfInstantiation());
 553     break;
 554   }
 555   case FunctionDecl::TK_FunctionTemplateSpecialization: {
 556     FunctionTemplateSpecializationInfo *
 557       FTSInfo = D->getTemplateSpecializationInfo();
 558
 559     RegisterTemplateSpecialization(FTSInfo->getTemplate(), D);
 560
 561     Record.AddDeclRef(FTSInfo->getTemplate());
 562     Record.push_back(FTSInfo->getTemplateSpecializationKind());
 563
 564     // Template arguments.
 565     Record.AddTemplateArgumentList(FTSInfo->TemplateArguments);
 566
 567     // Template args as written.
 568     Record.push_back(FTSInfo->TemplateArgumentsAsWritten != nullptr);
 569     if (FTSInfo->TemplateArgumentsAsWritten) {
 570       Record.push_back(FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs);
 571       for (int i=0, e = FTSInfo->TemplateArgumentsAsWritten->NumTemplateArgs;
 572              i!=e; ++i)
 573         Record.AddTemplateArgumentLoc(
 574             (*FTSInfo->TemplateArgumentsAsWritten)[i]);
 575       Record.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->LAngleLoc);
 576       Record.AddSourceLocation(FTSInfo->TemplateArgumentsAsWritten->RAngleLoc);
 577     }
 578
 579     Record.AddSourceLocation(FTSInfo->getPointOfInstantiation());
 580
 581     if (D->isCanonicalDecl()) {
 582       // Write the template that contains the specializations set. We will
 583       // add a FunctionTemplateSpecializationInfo to it when reading.
 584       Record.AddDeclRef(FTSInfo->getTemplate()->getCanonicalDecl());
 585     }
 586     break;
 587   }
 588   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
 589     DependentFunctionTemplateSpecializationInfo *
 590       DFTSInfo = D->getDependentSpecializationInfo();
 591
 592     // Templates.
 593     Record.push_back(DFTSInfo->getNumTemplates());
 594     for (int i=0, e = DFTSInfo->getNumTemplates(); i != e; ++i)
 595       Record.AddDeclRef(DFTSInfo->getTemplate(i));
 596
 597     // Templates args.
 598     Record.push_back(DFTSInfo->getNumTemplateArgs());
 599     for (int i=0, e = DFTSInfo->getNumTemplateArgs(); i != e; ++i)
 600       Record.AddTemplateArgumentLoc(DFTSInfo->getTemplateArg(i));
 601     Record.AddSourceLocation(DFTSInfo->getLAngleLoc());
 602     Record.AddSourceLocation(DFTSInfo->getRAngleLoc());
 603     break;
 604   }
 605   }
 606
 607   Record.push_back(D->param_size());
 608   for (auto P : D->parameters())
 609     Record.AddDeclRef(P);
 610   Code = serialization::DECL_FUNCTION;
 611 }
 612
 613 void ASTDeclWriter::VisitCXXDeductionGuideDecl(CXXDeductionGuideDecl *D) {
 614   VisitFunctionDecl(D);
 615   Record.push_back(D->IsCopyDeductionCandidate);
 616   Code = serialization::DECL_CXX_DEDUCTION_GUIDE;
 617 }
 618
 619 void ASTDeclWriter::VisitObjCMethodDecl(ObjCMethodDecl *D) {
 620   VisitNamedDecl(D);
 621   // FIXME: convert to LazyStmtPtr?
 622   // Unlike C/C++, method bodies will never be in header files.
 623   bool HasBodyStuff = D->getBody() != nullptr     ||
 624                       D->getSelfDecl() != nullptr || D->getCmdDecl() != nullptr;
 625   Record.push_back(HasBodyStuff);
 626   if (HasBodyStuff) {
 627     Record.AddStmt(D->getBody());
 628     Record.AddDeclRef(D->getSelfDecl());
 629     Record.AddDeclRef(D->getCmdDecl());
 630   }
 631   Record.push_back(D->isInstanceMethod());
 632   Record.push_back(D->isVariadic());
 633   Record.push_back(D->isPropertyAccessor());
 634   Record.push_back(D->isDefined());
 635   Record.push_back(D->IsOverriding);
 636   Record.push_back(D->HasSkippedBody);
 637
 638   Record.push_back(D->IsRedeclaration);
 639   Record.push_back(D->HasRedeclaration);
 640   if (D->HasRedeclaration) {
 641     assert(Context.getObjCMethodRedeclaration(D));
 642     Record.AddDeclRef(Context.getObjCMethodRedeclaration(D));
 643   }
 644
 645   // FIXME: stable encoding for @required/@optional
 646   Record.push_back(D->getImplementationControl());
 647   // FIXME: stable encoding for in/out/inout/bycopy/byref/oneway/nullability
 648   Record.push_back(D->getObjCDeclQualifier());
 649   Record.push_back(D->hasRelatedResultType());
 650   Record.AddTypeRef(D->getReturnType());
 651   Record.AddTypeSourceInfo(D->getReturnTypeSourceInfo());
 652   Record.AddSourceLocation(D->getLocEnd());
 653   Record.push_back(D->param_size());
 654   for (const auto *P : D->parameters())
 655     Record.AddDeclRef(P);
 656
 657   Record.push_back(D->SelLocsKind);
 658   unsigned NumStoredSelLocs = D->getNumStoredSelLocs();
 659   SourceLocation *SelLocs = D->getStoredSelLocs();
 660   Record.push_back(NumStoredSelLocs);
 661   for (unsigned i = 0; i != NumStoredSelLocs; ++i)
 662     Record.AddSourceLocation(SelLocs[i]);
 663
 664   Code = serialization::DECL_OBJC_METHOD;
 665 }
 666
 667 void ASTDeclWriter::VisitObjCTypeParamDecl(ObjCTypeParamDecl *D) {
 668   VisitTypedefNameDecl(D);
 669   Record.push_back(D->Variance);
 670   Record.push_back(D->Index);
 671   Record.AddSourceLocation(D->VarianceLoc);
 672   Record.AddSourceLocation(D->ColonLoc);
 673
 674   Code = serialization::DECL_OBJC_TYPE_PARAM;
 675 }
 676
 677 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
 678   VisitNamedDecl(D);
 679   Record.AddSourceLocation(D->getAtStartLoc());
 680   Record.AddSourceRange(D->getAtEndRange());
 681   // Abstract class (no need to define a stable serialization::DECL code).
 682 }
 683
 684 void ASTDeclWriter::VisitObjCInterfaceDecl(ObjCInterfaceDecl *D) {
 685   VisitRedeclarable(D);
 686   VisitObjCContainerDecl(D);
 687   Record.AddTypeRef(QualType(D->getTypeForDecl(), 0));
 688   AddObjCTypeParamList(D->TypeParamList);
 689
 690   Record.push_back(D->isThisDeclarationADefinition());
 691   if (D->isThisDeclarationADefinition()) {
 692     // Write the DefinitionData
 693     ObjCInterfaceDecl::DefinitionData &Data = D->data();
 694
 695     Record.AddTypeSourceInfo(D->getSuperClassTInfo());
 696     Record.AddSourceLocation(D->getEndOfDefinitionLoc());
 697     Record.push_back(Data.HasDesignatedInitializers);
 698
 699     // Write out the protocols that are directly referenced by the @interface.
 700     Record.push_back(Data.ReferencedProtocols.size());
 701     for (const auto *P : D->protocols())
 702       Record.AddDeclRef(P);
 703     for (const auto &PL : D->protocol_locs())
 704       Record.AddSourceLocation(PL);
 705
 706     // Write out the protocols that are transitively referenced.
 707     Record.push_back(Data.AllReferencedProtocols.size());
 708     for (ObjCList<ObjCProtocolDecl>::iterator
 709               P = Data.AllReferencedProtocols.begin(),
 710            PEnd = Data.AllReferencedProtocols.end();
 711          P != PEnd; ++P)
 712       Record.AddDeclRef(*P);
 713
 714
 715     if (ObjCCategoryDecl *Cat = D->getCategoryListRaw()) {
 716       // Ensure that we write out the set of categories for this class.
 717       Writer.ObjCClassesWithCategories.insert(D);
 718
 719       // Make sure that the categories get serialized.
 720       for (; Cat; Cat = Cat->getNextClassCategoryRaw())
 721         (void)Writer.GetDeclRef(Cat);
 722     }
 723   }
 724
 725   Code = serialization::DECL_OBJC_INTERFACE;
 726 }
 727
 728 void ASTDeclWriter::VisitObjCIvarDecl(ObjCIvarDecl *D) {
 729   VisitFieldDecl(D);
 730   // FIXME: stable encoding for @public/@private/@protected/@package
 731   Record.push_back(D->getAccessControl());
 732   Record.push_back(D->getSynthesize());
 733
 734   if (D->getDeclContext() == D->getLexicalDeclContext() &&
 735       !D->hasAttrs() &&
 736       !D->isImplicit() &&
 737       !D->isUsed(false) &&
 738       !D->isInvalidDecl() &&
 739       !D->isReferenced() &&
 740       !D->isModulePrivate() &&
 741       !D->getBitWidth() &&
 742       !D->hasExtInfo() &&
 743       D->getDeclName())
 744     AbbrevToUse = Writer.getDeclObjCIvarAbbrev();
 745
 746   Code = serialization::DECL_OBJC_IVAR;
 747 }
 748
 749 void ASTDeclWriter::VisitObjCProtocolDecl(ObjCProtocolDecl *D) {
 750   VisitRedeclarable(D);
 751   VisitObjCContainerDecl(D);
 752
 753   Record.push_back(D->isThisDeclarationADefinition());
 754   if (D->isThisDeclarationADefinition()) {
 755     Record.push_back(D->protocol_size());
 756     for (const auto *I : D->protocols())
 757       Record.AddDeclRef(I);
 758     for (const auto &PL : D->protocol_locs())
 759       Record.AddSourceLocation(PL);
 760   }
 761
 762   Code = serialization::DECL_OBJC_PROTOCOL;
 763 }
 764
 765 void ASTDeclWriter::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *D) {
 766   VisitFieldDecl(D);
 767   Code = serialization::DECL_OBJC_AT_DEFS_FIELD;
 768 }
 769
 770 void ASTDeclWriter::VisitObjCCategoryDecl(ObjCCategoryDecl *D) {
 771   VisitObjCContainerDecl(D);
 772   Record.AddSourceLocation(D->getCategoryNameLoc());
 773   Record.AddSourceLocation(D->getIvarLBraceLoc());
 774   Record.AddSourceLocation(D->getIvarRBraceLoc());
 775   Record.AddDeclRef(D->getClassInterface());
 776   AddObjCTypeParamList(D->TypeParamList);
 777   Record.push_back(D->protocol_size());
 778   for (const auto *I : D->protocols())
 779     Record.AddDeclRef(I);
 780   for (const auto &PL : D->protocol_locs())
 781     Record.AddSourceLocation(PL);
 782   Code = serialization::DECL_OBJC_CATEGORY;
 783 }
 784
 785 void ASTDeclWriter::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *D) {
 786   VisitNamedDecl(D);
 787   Record.AddDeclRef(D->getClassInterface());
 788   Code = serialization::DECL_OBJC_COMPATIBLE_ALIAS;
 789 }
 790
 791 void ASTDeclWriter::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
 792   VisitNamedDecl(D);
 793   Record.AddSourceLocation(D->getAtLoc());
 794   Record.AddSourceLocation(D->getLParenLoc());
 795   Record.AddTypeRef(D->getType());
 796   Record.AddTypeSourceInfo(D->getTypeSourceInfo());
 797   // FIXME: stable encoding
 798   Record.push_back((unsigned)D->getPropertyAttributes());
 799   Record.push_back((unsigned)D->getPropertyAttributesAsWritten());
 800   // FIXME: stable encoding
 801   Record.push_back((unsigned)D->getPropertyImplementation());
 802   Record.AddDeclarationName(D->getGetterName());
 803   Record.AddSourceLocation(D->getGetterNameLoc());
 804   Record.AddDeclarationName(D->getSetterName());
 805   Record.AddSourceLocation(D->getSetterNameLoc());
 806   Record.AddDeclRef(D->getGetterMethodDecl());
 807   Record.AddDeclRef(D->getSetterMethodDecl());
 808   Record.AddDeclRef(D->getPropertyIvarDecl());
 809   Code = serialization::DECL_OBJC_PROPERTY;
 810 }
 811
 812 void ASTDeclWriter::VisitObjCImplDecl(ObjCImplDecl *D) {
 813   VisitObjCContainerDecl(D);
 814   Record.AddDeclRef(D->getClassInterface());
 815   // Abstract class (no need to define a stable serialization::DECL code).
 816 }
 817
 818 void ASTDeclWriter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
 819   VisitObjCImplDecl(D);
 820   Record.AddSourceLocation(D->getCategoryNameLoc());
 821   Code = serialization::DECL_OBJC_CATEGORY_IMPL;
 822 }
 823
 824 void ASTDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
 825   VisitObjCImplDecl(D);
 826   Record.AddDeclRef(D->getSuperClass());
 827   Record.AddSourceLocation(D->getSuperClassLoc());
 828   Record.AddSourceLocation(D->getIvarLBraceLoc());
 829   Record.AddSourceLocation(D->getIvarRBraceLoc());
 830   Record.push_back(D->hasNonZeroConstructors());
 831   Record.push_back(D->hasDestructors());
 832   Record.push_back(D->NumIvarInitializers);
 833   if (D->NumIvarInitializers)
 834     Record.AddCXXCtorInitializers(
 835         llvm::makeArrayRef(D->init_begin(), D->init_end()));
 836   Code = serialization::DECL_OBJC_IMPLEMENTATION;
 837 }
 838
 839 void ASTDeclWriter::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
 840   VisitDecl(D);
 841   Record.AddSourceLocation(D->getLocStart());
 842   Record.AddDeclRef(D->getPropertyDecl());
 843   Record.AddDeclRef(D->getPropertyIvarDecl());
 844   Record.AddSourceLocation(D->getPropertyIvarDeclLoc());
 845   Record.AddStmt(D->getGetterCXXConstructor());
 846   Record.AddStmt(D->getSetterCXXAssignment());
 847   Code = serialization::DECL_OBJC_PROPERTY_IMPL;
 848 }
 849
 850 void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
 851   VisitDeclaratorDecl(D);
 852   Record.push_back(D->isMutable());
 853
 854   FieldDecl::InitStorageKind ISK = D->InitStorage.getInt();
 855   Record.push_back(ISK);
 856   if (ISK == FieldDecl::ISK_CapturedVLAType)
 857     Record.AddTypeRef(QualType(D->getCapturedVLAType(), 0));
 858   else if (ISK)
 859     Record.AddStmt(D->getInClassInitializer());
 860
 861   Record.AddStmt(D->getBitWidth());
 862
 863   if (!D->getDeclName())
 864     Record.AddDeclRef(Context.getInstantiatedFromUnnamedFieldDecl(D));
 865
 866   if (D->getDeclContext() == D->getLexicalDeclContext() &&
 867       !D->hasAttrs() &&
 868       !D->isImplicit() &&
 869       !D->isUsed(false) &&
 870       !D->isInvalidDecl() &&
 871       !D->isReferenced() &&
 872       !D->isTopLevelDeclInObjCContainer() &&
 873       !D->isModulePrivate() &&
 874       !D->getBitWidth() &&
 875       !D->hasInClassInitializer() &&
 876       !D->hasCapturedVLAType() &&
 877       !D->hasExtInfo() &&
 878       !ObjCIvarDecl::classofKind(D->getKind()) &&
 879       !ObjCAtDefsFieldDecl::classofKind(D->getKind()) &&
 880       D->getDeclName())
 881     AbbrevToUse = Writer.getDeclFieldAbbrev();
 882
 883   Code = serialization::DECL_FIELD;
 884 }
 885
 886 void ASTDeclWriter::VisitMSPropertyDecl(MSPropertyDecl *D) {
 887   VisitDeclaratorDecl(D);
 888   Record.AddIdentifierRef(D->getGetterId());
 889   Record.AddIdentifierRef(D->getSetterId());
 890   Code = serialization::DECL_MS_PROPERTY;
 891 }
 892
 893 void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
 894   VisitValueDecl(D);
 895   Record.push_back(D->getChainingSize());
 896
 897   for (const auto *P : D->chain())
 898     Record.AddDeclRef(P);
 899   Code = serialization::DECL_INDIRECTFIELD;
 900 }
 901
 902 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
 903   VisitRedeclarable(D);
 904   VisitDeclaratorDecl(D);
 905   Record.push_back(D->getStorageClass());
 906   Record.push_back(D->getTSCSpec());
 907   Record.push_back(D->getInitStyle());
 908   if (!isa<ParmVarDecl>(D)) {
 909     Record.push_back(D->isThisDeclarationADemotedDefinition());
 910     Record.push_back(D->isExceptionVariable());
 911     Record.push_back(D->isNRVOVariable());
 912     Record.push_back(D->isCXXForRangeDecl());
 913     Record.push_back(D->isARCPseudoStrong());
 914     Record.push_back(D->isInline());
 915     Record.push_back(D->isInlineSpecified());
 916     Record.push_back(D->isConstexpr());
 917     Record.push_back(D->isInitCapture());
 918     Record.push_back(D->isPreviousDeclInSameBlockScope());
 919     if (const auto *IPD = dyn_cast<ImplicitParamDecl>(D))
 920       Record.push_back(static_cast<unsigned>(IPD->getParameterKind()));
 921     else
 922       Record.push_back(0);
 923   }
 924   Record.push_back(D->getLinkageInternal());
 925
 926   if (D->getInit()) {
 927     Record.push_back(!D->isInitKnownICE() ? 1 : (D->isInitICE() ? 3 : 2));
 928     Record.AddStmt(D->getInit());
 929   } else {
 930     Record.push_back(0);
 931   }
 932
 933   if (D->getStorageDuration() == SD_Static) {
 934     bool ModulesCodegen = false;
 935     if (Writer.WritingModule &&
 936         !D->getDescribedVarTemplate() && !D->getMemberSpecializationInfo() &&
 937         !isa<VarTemplateSpecializationDecl>(D)) {
 938       // When building a C++ Modules TS module interface unit, a strong
 939       // definition in the module interface is provided by the compilation of
 940       // that module interface unit, not by its users. (Inline variables are
 941       // still emitted in module users.)
 942       ModulesCodegen =
 943           (Writer.WritingModule->Kind == Module::ModuleInterfaceUnit &&
 944            Writer.Context->GetGVALinkageForVariable(D) == GVA_StrongExternal);
 945     }
 946     Record.push_back(ModulesCodegen);
 947     if (ModulesCodegen)
 948       Writer.ModularCodegenDecls.push_back(Writer.GetDeclRef(D));
 949   }
 950
 951   enum {
 952     VarNotTemplate = 0, VarTemplate, StaticDataMemberSpecialization
 953   };
 954   if (VarTemplateDecl *TemplD = D->getDescribedVarTemplate()) {
 955     Record.push_back(VarTemplate);
 956     Record.AddDeclRef(TemplD);
 957   } else if (MemberSpecializationInfo *SpecInfo
 958                = D->getMemberSpecializationInfo()) {
 959     Record.push_back(StaticDataMemberSpecialization);
 960     Record.AddDeclRef(SpecInfo->getInstantiatedFrom());
 961     Record.push_back(SpecInfo->getTemplateSpecializationKind());
 962     Record.AddSourceLocation(SpecInfo->getPointOfInstantiation());
 963   } else {
 964     Record.push_back(VarNotTemplate);
 965   }
 966
 967   if (D->getDeclContext() == D->getLexicalDeclContext() &&
 968       !D->hasAttrs() &&
 969       !D->isImplicit() &&
 970       !D->isUsed(false) &&
 971       !D->isInvalidDecl() &&
 972       !D->isReferenced() &&
 973       !D->isTopLevelDeclInObjCContainer() &&
 974       D->getAccess() == AS_none &&
 975       !D->isModulePrivate() &&
 976       !needsAnonymousDeclarationNumber(D) &&
 977       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
 978       !D->hasExtInfo() &&
 979       D->getFirstDecl() == D->getMostRecentDecl() &&
 980       D->getKind() == Decl::Var &&
 981       !D->isInline() &&
 982       !D->isConstexpr() &&
 983       !D->isInitCapture() &&
 984       !D->isPreviousDeclInSameBlockScope() &&
 985       D->getStorageDuration() != SD_Static &&
 986       !D->getMemberSpecializationInfo())
 987     AbbrevToUse = Writer.getDeclVarAbbrev();
 988
 989   Code = serialization::DECL_VAR;
 990 }
 991
 992 void ASTDeclWriter::VisitImplicitParamDecl(ImplicitParamDecl *D) {
 993   VisitVarDecl(D);
 994   Code = serialization::DECL_IMPLICIT_PARAM;
 995 }
 996
 997 void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
 998   VisitVarDecl(D);
 999   Record.push_back(D->isObjCMethodParameter());
1000   Record.push_back(D->getFunctionScopeDepth());
1001   Record.push_back(D->getFunctionScopeIndex());
1002   Record.push_back(D->getObjCDeclQualifier()); // FIXME: stable encoding
1003   Record.push_back(D->isKNRPromoted());
1004   Record.push_back(D->hasInheritedDefaultArg());
1005   Record.push_back(D->hasUninstantiatedDefaultArg());
1006   if (D->hasUninstantiatedDefaultArg())
1007     Record.AddStmt(D->getUninstantiatedDefaultArg());
1008   Code = serialization::DECL_PARM_VAR;
1009
1010   assert(!D->isARCPseudoStrong()); // can be true of ImplicitParamDecl
1011
1012   // If the assumptions about the DECL_PARM_VAR abbrev are true, use it.  Here
1013   // we dynamically check for the properties that we optimize for, but don't
1014   // know are true of all PARM_VAR_DECLs.
1015   if (D->getDeclContext() == D->getLexicalDeclContext() &&
1016       !D->hasAttrs() &&
1017       !D->hasExtInfo() &&
1018       !D->isImplicit() &&
1019       !D->isUsed(false) &&
1020       !D->isInvalidDecl() &&
1021       !D->isReferenced() &&
1022       D->getAccess() == AS_none &&
1023       !D->isModulePrivate() &&
1024       D->getStorageClass() == 0 &&
1025       D->getInitStyle() == VarDecl::CInit && // Can params have anything else?
1026       D->getFunctionScopeDepth() == 0 &&
1027       D->getObjCDeclQualifier() == 0 &&
1028       !D->isKNRPromoted() &&
1029       !D->hasInheritedDefaultArg() &&
1030       D->getInit() == nullptr &&
1031       !D->hasUninstantiatedDefaultArg())  // No default expr.
1032     AbbrevToUse = Writer.getDeclParmVarAbbrev();
1033
1034   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
1035   // just us assuming it.
1036   assert(!D->getTSCSpec() && "PARM_VAR_DECL can't use TLS");
1037   assert(!D->isThisDeclarationADemotedDefinition()
1038          && "PARM_VAR_DECL can't be demoted definition.");
1039   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
1040   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
1041   assert(D->getPreviousDecl() == nullptr && "PARM_VAR_DECL can't be redecl");
1042   assert(!D->isStaticDataMember() &&
1043          "PARM_VAR_DECL can't be static data member");
1044 }
1045
1046 void ASTDeclWriter::VisitDecompositionDecl(DecompositionDecl *D) {
1047   // Record the number of bindings first to simplify deserialization.
1048   Record.push_back(D->bindings().size());
1049
1050   VisitVarDecl(D);
1051   for (auto *B : D->bindings())
1052     Record.AddDeclRef(B);
1053   Code = serialization::DECL_DECOMPOSITION;
1054 }
1055
1056 void ASTDeclWriter::VisitBindingDecl(BindingDecl *D) {
1057   VisitValueDecl(D);
1058   Record.AddStmt(D->getBinding());
1059   Code = serialization::DECL_BINDING;
1060 }
1061
1062 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
1063   VisitDecl(D);
1064   Record.AddStmt(D->getAsmString());
1065   Record.AddSourceLocation(D->getRParenLoc());
1066   Code = serialization::DECL_FILE_SCOPE_ASM;
1067 }
1068
1069 void ASTDeclWriter::VisitEmptyDecl(EmptyDecl *D) {
1070   VisitDecl(D);
1071   Code = serialization::DECL_EMPTY;
1072 }
1073
1074 void ASTDeclWriter::VisitBlockDecl(BlockDecl *D) {
1075   VisitDecl(D);
1076   Record.AddStmt(D->getBody());
1077   Record.AddTypeSourceInfo(D->getSignatureAsWritten());
1078   Record.push_back(D->param_size());
1079   for (ParmVarDecl *P : D->parameters())
1080     Record.AddDeclRef(P);
1081   Record.push_back(D->isVariadic());
1082   Record.push_back(D->blockMissingReturnType());
1083   Record.push_back(D->isConversionFromLambda());
1084   Record.push_back(D->capturesCXXThis());
1085   Record.push_back(D->getNumCaptures());
1086   for (const auto &capture : D->captures()) {
1087     Record.AddDeclRef(capture.getVariable());
1088
1089     unsigned flags = 0;
1090     if (capture.isByRef()) flags |= 1;
1091     if (capture.isNested()) flags |= 2;
1092     if (capture.hasCopyExpr()) flags |= 4;
1093     Record.push_back(flags);
1094
1095     if (capture.hasCopyExpr()) Record.AddStmt(capture.getCopyExpr());
1096   }
1097
1098   Code = serialization::DECL_BLOCK;
1099 }
1100
1101 void ASTDeclWriter::VisitCapturedDecl(CapturedDecl *CD) {
1102   Record.push_back(CD->getNumParams());
1103   VisitDecl(CD);
1104   Record.push_back(CD->getContextParamPosition());
1105   Record.push_back(CD->isNothrow() ? 1 : 0);
1106   // Body is stored by VisitCapturedStmt.
1107   for (unsigned I = 0; I < CD->getNumParams(); ++I)
1108     Record.AddDeclRef(CD->getParam(I));
1109   Code = serialization::DECL_CAPTURED;
1110 }
1111
1112 void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
1113   VisitDecl(D);
1114   Record.push_back(D->getLanguage());
1115   Record.AddSourceLocation(D->getExternLoc());
1116   Record.AddSourceLocation(D->getRBraceLoc());
1117   Code = serialization::DECL_LINKAGE_SPEC;
1118 }
1119
1120 void ASTDeclWriter::VisitExportDecl(ExportDecl *D) {
1121   VisitDecl(D);
1122   Record.AddSourceLocation(D->getRBraceLoc());
1123   Code = serialization::DECL_EXPORT;
1124 }
1125
1126 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
1127   VisitNamedDecl(D);
1128   Record.AddSourceLocation(D->getLocStart());
1129   Code = serialization::DECL_LABEL;
1130 }
1131
1132
1133 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
1134   VisitRedeclarable(D);
1135   VisitNamedDecl(D);
1136   Record.push_back(D->isInline());
1137   Record.AddSourceLocation(D->getLocStart());
1138   Record.AddSourceLocation(D->getRBraceLoc());
1139
1140   if (D->isOriginalNamespace())
1141     Record.AddDeclRef(D->getAnonymousNamespace());
1142   Code = serialization::DECL_NAMESPACE;
1143
1144   if (Writer.hasChain() && D->isAnonymousNamespace() &&
1145       D == D->getMostRecentDecl()) {
1146     // This is a most recent reopening of the anonymous namespace. If its parent
1147     // is in a previous PCH (or is the TU), mark that parent for update, because
1148     // the original namespace always points to the latest re-opening of its
1149     // anonymous namespace.
1150     Decl *Parent = cast<Decl>(
1151         D->getParent()->getRedeclContext()->getPrimaryContext());
1152     if (Parent->isFromASTFile() || isa<TranslationUnitDecl>(Parent)) {
1153       Writer.DeclUpdates[Parent].push_back(
1154           ASTWriter::DeclUpdate(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE, D));
1155     }
1156   }
1157 }
1158
1159 void ASTDeclWriter::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
1160   VisitRedeclarable(D);
1161   VisitNamedDecl(D);
1162   Record.AddSourceLocation(D->getNamespaceLoc());
1163   Record.AddSourceLocation(D->getTargetNameLoc());
1164   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1165   Record.AddDeclRef(D->getNamespace());
1166   Code = serialization::DECL_NAMESPACE_ALIAS;
1167 }
1168
1169 void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
1170   VisitNamedDecl(D);
1171   Record.AddSourceLocation(D->getUsingLoc());
1172   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1173   Record.AddDeclarationNameLoc(D->DNLoc, D->getDeclName());
1174   Record.AddDeclRef(D->FirstUsingShadow.getPointer());
1175   Record.push_back(D->hasTypename());
1176   Record.AddDeclRef(Context.getInstantiatedFromUsingDecl(D));
1177   Code = serialization::DECL_USING;
1178 }
1179
1180 void ASTDeclWriter::VisitUsingPackDecl(UsingPackDecl *D) {
1181   Record.push_back(D->NumExpansions);
1182   VisitNamedDecl(D);
1183   Record.AddDeclRef(D->getInstantiatedFromUsingDecl());
1184   for (auto *E : D->expansions())
1185     Record.AddDeclRef(E);
1186   Code = serialization::DECL_USING_PACK;
1187 }
1188
1189 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
1190   VisitRedeclarable(D);
1191   VisitNamedDecl(D);
1192   Record.AddDeclRef(D->getTargetDecl());
1193   Record.AddDeclRef(D->UsingOrNextShadow);
1194   Record.AddDeclRef(Context.getInstantiatedFromUsingShadowDecl(D));
1195   Code = serialization::DECL_USING_SHADOW;
1196 }
1197
1198 void ASTDeclWriter::VisitConstructorUsingShadowDecl(
1199     ConstructorUsingShadowDecl *D) {
1200   VisitUsingShadowDecl(D);
1201   Record.AddDeclRef(D->NominatedBaseClassShadowDecl);
1202   Record.AddDeclRef(D->ConstructedBaseClassShadowDecl);
1203   Record.push_back(D->IsVirtual);
1204   Code = serialization::DECL_CONSTRUCTOR_USING_SHADOW;
1205 }
1206
1207 void ASTDeclWriter::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
1208   VisitNamedDecl(D);
1209   Record.AddSourceLocation(D->getUsingLoc());
1210   Record.AddSourceLocation(D->getNamespaceKeyLocation());
1211   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1212   Record.AddDeclRef(D->getNominatedNamespace());
1213   Record.AddDeclRef(dyn_cast<Decl>(D->getCommonAncestor()));
1214   Code = serialization::DECL_USING_DIRECTIVE;
1215 }
1216
1217 void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
1218   VisitValueDecl(D);
1219   Record.AddSourceLocation(D->getUsingLoc());
1220   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1221   Record.AddDeclarationNameLoc(D->DNLoc, D->getDeclName());
1222   Record.AddSourceLocation(D->getEllipsisLoc());
1223   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
1224 }
1225
1226 void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
1227                                                UnresolvedUsingTypenameDecl *D) {
1228   VisitTypeDecl(D);
1229   Record.AddSourceLocation(D->getTypenameLoc());
1230   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
1231   Record.AddSourceLocation(D->getEllipsisLoc());
1232   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
1233 }
1234
1235 void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) {
1236   VisitRecordDecl(D);
1237
1238   enum {
1239     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
1240   };
1241   if (ClassTemplateDecl *TemplD = D->getDescribedClassTemplate()) {
1242     Record.push_back(CXXRecTemplate);
1243     Record.AddDeclRef(TemplD);
1244   } else if (MemberSpecializationInfo *MSInfo
1245                = D->getMemberSpecializationInfo()) {
1246     Record.push_back(CXXRecMemberSpecialization);
1247     Record.AddDeclRef(MSInfo->getInstantiatedFrom());
1248     Record.push_back(MSInfo->getTemplateSpecializationKind());
1249     Record.AddSourceLocation(MSInfo->getPointOfInstantiation());
1250   } else {
1251     Record.push_back(CXXRecNotTemplate);
1252   }
1253
1254   Record.push_back(D->isThisDeclarationADefinition());
1255   if (D->isThisDeclarationADefinition())
1256     Record.AddCXXDefinitionData(D);
1257
1258   // Store (what we currently believe to be) the key function to avoid
1259   // deserializing every method so we can compute it.
1260   if (D->IsCompleteDefinition)
1261     Record.AddDeclRef(Context.getCurrentKeyFunction(D));
1262
1263   Code = serialization::DECL_CXX_RECORD;
1264 }
1265
1266 void ASTDeclWriter::VisitCXXMethodDecl(CXXMethodDecl *D) {
1267   VisitFunctionDecl(D);
1268   if (D->isCanonicalDecl()) {
1269     Record.push_back(D->size_overridden_methods());
1270     for (const CXXMethodDecl *MD : D->overridden_methods())
1271       Record.AddDeclRef(MD);
1272   } else {
1273     // We only need to record overridden methods once for the canonical decl.
1274     Record.push_back(0);
1275   }
1276
1277   if (D->getDeclContext() == D->getLexicalDeclContext() &&
1278       D->getFirstDecl() == D->getMostRecentDecl() &&
1279       !D->isInvalidDecl() &&
1280       !D->hasAttrs() &&
1281       !D->isTopLevelDeclInObjCContainer() &&
1282       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
1283       !D->hasExtInfo() &&
1284       !D->hasInheritedPrototype() &&
1285       D->hasWrittenPrototype())
1286     AbbrevToUse = Writer.getDeclCXXMethodAbbrev();
1287
1288   Code = serialization::DECL_CXX_METHOD;
1289 }
1290
1291 void ASTDeclWriter::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
1292   if (auto Inherited = D->getInheritedConstructor()) {
1293     Record.AddDeclRef(Inherited.getShadowDecl());
1294     Record.AddDeclRef(Inherited.getConstructor());
1295     Code = serialization::DECL_CXX_INHERITED_CONSTRUCTOR;
1296   } else {
1297     Code = serialization::DECL_CXX_CONSTRUCTOR;
1298   }
1299
1300   VisitCXXMethodDecl(D);
1301
1302   Code = D->isInheritingConstructor()
1303              ? serialization::DECL_CXX_INHERITED_CONSTRUCTOR
1304              : serialization::DECL_CXX_CONSTRUCTOR;
1305 }
1306
1307 void ASTDeclWriter::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
1308   VisitCXXMethodDecl(D);
1309
1310   Record.AddDeclRef(D->getOperatorDelete());
1311   if (D->getOperatorDelete())
1312     Record.AddStmt(D->getOperatorDeleteThisArg());
1313
1314   Code = serialization::DECL_CXX_DESTRUCTOR;
1315 }
1316
1317 void ASTDeclWriter::VisitCXXConversionDecl(CXXConversionDecl *D) {
1318   VisitCXXMethodDecl(D);
1319   Code = serialization::DECL_CXX_CONVERSION;
1320 }
1321
1322 void ASTDeclWriter::VisitImportDecl(ImportDecl *D) {
1323   VisitDecl(D);
1324   Record.push_back(Writer.getSubmoduleID(D->getImportedModule()));
1325   ArrayRef<SourceLocation> IdentifierLocs = D->getIdentifierLocs();
1326   Record.push_back(!IdentifierLocs.empty());
1327   if (IdentifierLocs.empty()) {
1328     Record.AddSourceLocation(D->getLocEnd());
1329     Record.push_back(1);
1330   } else {
1331     for (unsigned I = 0, N = IdentifierLocs.size(); I != N; ++I)
1332       Record.AddSourceLocation(IdentifierLocs[I]);
1333     Record.push_back(IdentifierLocs.size());
1334   }
1335   // Note: the number of source locations must always be the last element in
1336   // the record.
1337   Code = serialization::DECL_IMPORT;
1338 }
1339
1340 void ASTDeclWriter::VisitAccessSpecDecl(AccessSpecDecl *D) {
1341   VisitDecl(D);
1342   Record.AddSourceLocation(D->getColonLoc());
1343   Code = serialization::DECL_ACCESS_SPEC;
1344 }
1345
1346 void ASTDeclWriter::VisitFriendDecl(FriendDecl *D) {
1347   // Record the number of friend type template parameter lists here
1348   // so as to simplify memory allocation during deserialization.
1349   Record.push_back(D->NumTPLists);
1350   VisitDecl(D);
1351   bool hasFriendDecl = D->Friend.is<NamedDecl*>();
1352   Record.push_back(hasFriendDecl);
1353   if (hasFriendDecl)
1354     Record.AddDeclRef(D->getFriendDecl());
1355   else
1356     Record.AddTypeSourceInfo(D->getFriendType());
1357   for (unsigned i = 0; i < D->NumTPLists; ++i)
1358     Record.AddTemplateParameterList(D->getFriendTypeTemplateParameterList(i));
1359   Record.AddDeclRef(D->getNextFriend());
1360   Record.push_back(D->UnsupportedFriend);
1361   Record.AddSourceLocation(D->FriendLoc);
1362   Code = serialization::DECL_FRIEND;
1363 }
1364
1365 void ASTDeclWriter::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
1366   VisitDecl(D);
1367   Record.push_back(D->getNumTemplateParameters());
1368   for (unsigned i = 0, e = D->getNumTemplateParameters(); i != e; ++i)
1369     Record.AddTemplateParameterList(D->getTemplateParameterList(i));
1370   Record.push_back(D->getFriendDecl() != nullptr);
1371   if (D->getFriendDecl())
1372     Record.AddDeclRef(D->getFriendDecl());
1373   else
1374     Record.AddTypeSourceInfo(D->getFriendType());
1375   Record.AddSourceLocation(D->getFriendLoc());
1376   Code = serialization::DECL_FRIEND_TEMPLATE;
1377 }
1378
1379 void ASTDeclWriter::VisitTemplateDecl(TemplateDecl *D) {
1380   VisitNamedDecl(D);
1381
1382   Record.AddDeclRef(D->getTemplatedDecl());
1383   Record.AddTemplateParameterList(D->getTemplateParameters());
1384 }
1385
1386 void ASTDeclWriter::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
1387   VisitRedeclarable(D);
1388
1389   // Emit data to initialize CommonOrPrev before VisitTemplateDecl so that
1390   // getCommonPtr() can be used while this is still initializing.
1391   if (D->isFirstDecl()) {
1392     // This declaration owns the 'common' pointer, so serialize that data now.
1393     Record.AddDeclRef(D->getInstantiatedFromMemberTemplate());
1394     if (D->getInstantiatedFromMemberTemplate())
1395       Record.push_back(D->isMemberSpecialization());
1396   }
1397
1398   VisitTemplateDecl(D);
1399   Record.push_back(D->getIdentifierNamespace());
1400 }
1401
1402 void ASTDeclWriter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
1403   VisitRedeclarableTemplateDecl(D);
1404
1405   if (D->isFirstDecl())
1406     AddTemplateSpecializations(D);
1407   Code = serialization::DECL_CLASS_TEMPLATE;
1408 }
1409
1410 void ASTDeclWriter::VisitClassTemplateSpecializationDecl(
1411                                            ClassTemplateSpecializationDecl *D) {
1412   RegisterTemplateSpecialization(D->getSpecializedTemplate(), D);
1413
1414   VisitCXXRecordDecl(D);
1415
1416   llvm::PointerUnion<ClassTemplateDecl *,
1417                      ClassTemplatePartialSpecializationDecl *> InstFrom
1418     = D->getSpecializedTemplateOrPartial();
1419   if (Decl *InstFromD = InstFrom.dyn_cast<ClassTemplateDecl *>()) {
1420     Record.AddDeclRef(InstFromD);
1421   } else {
1422     Record.AddDeclRef(InstFrom.get<ClassTemplatePartialSpecializationDecl *>());
1423     Record.AddTemplateArgumentList(&D->getTemplateInstantiationArgs());
1424   }
1425
1426   Record.AddTemplateArgumentList(&D->getTemplateArgs());
1427   Record.AddSourceLocation(D->getPointOfInstantiation());
1428   Record.push_back(D->getSpecializationKind());
1429   Record.push_back(D->isCanonicalDecl());
1430
1431   if (D->isCanonicalDecl()) {
1432     // When reading, we'll add it to the folding set of the following template.
1433     Record.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl());
1434   }
1435
1436   // Explicit info.
1437   Record.AddTypeSourceInfo(D->getTypeAsWritten());
1438   if (D->getTypeAsWritten()) {
1439     Record.AddSourceLocation(D->getExternLoc());
1440     Record.AddSourceLocation(D->getTemplateKeywordLoc());
1441   }
1442
1443   Code = serialization::DECL_CLASS_TEMPLATE_SPECIALIZATION;
1444 }
1445
1446 void ASTDeclWriter::VisitClassTemplatePartialSpecializationDecl(
1447                                     ClassTemplatePartialSpecializationDecl *D) {
1448   VisitClassTemplateSpecializationDecl(D);
1449
1450   Record.AddTemplateParameterList(D->getTemplateParameters());
1451   Record.AddASTTemplateArgumentListInfo(D->getTemplateArgsAsWritten());
1452
1453   // These are read/set from/to the first declaration.
1454   if (D->getPreviousDecl() == nullptr) {
1455     Record.AddDeclRef(D->getInstantiatedFromMember());
1456     Record.push_back(D->isMemberSpecialization());
1457   }
1458
1459   Code = serialization::DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION;
1460 }
1461
1462 void ASTDeclWriter::VisitVarTemplateDecl(VarTemplateDecl *D) {
1463   VisitRedeclarableTemplateDecl(D);
1464
1465   if (D->isFirstDecl())
1466     AddTemplateSpecializations(D);
1467   Code = serialization::DECL_VAR_TEMPLATE;
1468 }
1469
1470 void ASTDeclWriter::VisitVarTemplateSpecializationDecl(
1471     VarTemplateSpecializationDecl *D) {
1472   RegisterTemplateSpecialization(D->getSpecializedTemplate(), D);
1473
1474   VisitVarDecl(D);
1475
1476   llvm::PointerUnion<VarTemplateDecl *, VarTemplatePartialSpecializationDecl *>
1477   InstFrom = D->getSpecializedTemplateOrPartial();
1478   if (Decl *InstFromD = InstFrom.dyn_cast<VarTemplateDecl *>()) {
1479     Record.AddDeclRef(InstFromD);
1480   } else {
1481     Record.AddDeclRef(InstFrom.get<VarTemplatePartialSpecializationDecl *>());
1482     Record.AddTemplateArgumentList(&D->getTemplateInstantiationArgs());
1483   }
1484
1485   // Explicit info.
1486   Record.AddTypeSourceInfo(D->getTypeAsWritten());
1487   if (D->getTypeAsWritten()) {
1488     Record.AddSourceLocation(D->getExternLoc());
1489     Record.AddSourceLocation(D->getTemplateKeywordLoc());
1490   }
1491
1492   Record.AddTemplateArgumentList(&D->getTemplateArgs());
1493   Record.AddSourceLocation(D->getPointOfInstantiation());
1494   Record.push_back(D->getSpecializationKind());
1495   Record.push_back(D->IsCompleteDefinition);
1496   Record.push_back(D->isCanonicalDecl());
1497
1498   if (D->isCanonicalDecl()) {
1499     // When reading, we'll add it to the folding set of the following template.
1500     Record.AddDeclRef(D->getSpecializedTemplate()->getCanonicalDecl());
1501   }
1502
1503   Code = serialization::DECL_VAR_TEMPLATE_SPECIALIZATION;
1504 }
1505
1506 void ASTDeclWriter::VisitVarTemplatePartialSpecializationDecl(
1507     VarTemplatePartialSpecializationDecl *D) {
1508   VisitVarTemplateSpecializationDecl(D);
1509
1510   Record.AddTemplateParameterList(D->getTemplateParameters());
1511   Record.AddASTTemplateArgumentListInfo(D->getTemplateArgsAsWritten());
1512
1513   // These are read/set from/to the first declaration.
1514   if (D->getPreviousDecl() == nullptr) {
1515     Record.AddDeclRef(D->getInstantiatedFromMember());
1516     Record.push_back(D->isMemberSpecialization());
1517   }
1518
1519   Code = serialization::DECL_VAR_TEMPLATE_PARTIAL_SPECIALIZATION;
1520 }
1521
1522 void ASTDeclWriter::VisitClassScopeFunctionSpecializationDecl(
1523                                     ClassScopeFunctionSpecializationDecl *D) {
1524   VisitDecl(D);
1525   Record.AddDeclRef(D->getSpecialization());
1526   Code = serialization::DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION;
1527 }
1528
1529
1530 void ASTDeclWriter::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
1531   VisitRedeclarableTemplateDecl(D);
1532
1533   if (D->isFirstDecl())
1534     AddTemplateSpecializations(D);
1535   Code = serialization::DECL_FUNCTION_TEMPLATE;
1536 }
1537
1538 void ASTDeclWriter::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
1539   VisitTypeDecl(D);
1540
1541   Record.push_back(D->wasDeclaredWithTypename());
1542
1543   bool OwnsDefaultArg = D->hasDefaultArgument() &&
1544                         !D->defaultArgumentWasInherited();
1545   Record.push_back(OwnsDefaultArg);
1546   if (OwnsDefaultArg)
1547     Record.AddTypeSourceInfo(D->getDefaultArgumentInfo());
1548
1549   Code = serialization::DECL_TEMPLATE_TYPE_PARM;
1550 }
1551
1552 void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
1553   // For an expanded parameter pack, record the number of expansion types here
1554   // so that it's easier for deserialization to allocate the right amount of
1555   // memory.
1556   if (D->isExpandedParameterPack())
1557     Record.push_back(D->getNumExpansionTypes());
1558
1559   VisitDeclaratorDecl(D);
1560   // TemplateParmPosition.
1561   Record.push_back(D->getDepth());
1562   Record.push_back(D->getPosition());
1563
1564   if (D->isExpandedParameterPack()) {
1565     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
1566       Record.AddTypeRef(D->getExpansionType(I));
1567       Record.AddTypeSourceInfo(D->getExpansionTypeSourceInfo(I));
1568     }
1569
1570     Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
1571   } else {
1572     // Rest of NonTypeTemplateParmDecl.
1573     Record.push_back(D->isParameterPack());
1574     bool OwnsDefaultArg = D->hasDefaultArgument() &&
1575                           !D->defaultArgumentWasInherited();
1576     Record.push_back(OwnsDefaultArg);
1577     if (OwnsDefaultArg)
1578       Record.AddStmt(D->getDefaultArgument());
1579     Code = serialization::DECL_NON_TYPE_TEMPLATE_PARM;
1580   }
1581 }
1582
1583 void ASTDeclWriter::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
1584   // For an expanded parameter pack, record the number of expansion types here
1585   // so that it's easier for deserialization to allocate the right amount of
1586   // memory.
1587   if (D->isExpandedParameterPack())
1588     Record.push_back(D->getNumExpansionTemplateParameters());
1589
1590   VisitTemplateDecl(D);
1591   // TemplateParmPosition.
1592   Record.push_back(D->getDepth());
1593   Record.push_back(D->getPosition());
1594
1595   if (D->isExpandedParameterPack()) {
1596     for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
1597          I != N; ++I)
1598       Record.AddTemplateParameterList(D->getExpansionTemplateParameters(I));
1599     Code = serialization::DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK;
1600   } else {
1601     // Rest of TemplateTemplateParmDecl.
1602     Record.push_back(D->isParameterPack());
1603     bool OwnsDefaultArg = D->hasDefaultArgument() &&
1604                           !D->defaultArgumentWasInherited();
1605     Record.push_back(OwnsDefaultArg);
1606     if (OwnsDefaultArg)
1607       Record.AddTemplateArgumentLoc(D->getDefaultArgument());
1608     Code = serialization::DECL_TEMPLATE_TEMPLATE_PARM;
1609   }
1610 }
1611
1612 void ASTDeclWriter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
1613   VisitRedeclarableTemplateDecl(D);
1614   Code = serialization::DECL_TYPE_ALIAS_TEMPLATE;
1615 }
1616
1617 void ASTDeclWriter::VisitStaticAssertDecl(StaticAssertDecl *D) {
1618   VisitDecl(D);
1619   Record.AddStmt(D->getAssertExpr());
1620   Record.push_back(D->isFailed());
1621   Record.AddStmt(D->getMessage());
1622   Record.AddSourceLocation(D->getRParenLoc());
1623   Code = serialization::DECL_STATIC_ASSERT;
1624 }
1625
1626 /// \brief Emit the DeclContext part of a declaration context decl.
1627 void ASTDeclWriter::VisitDeclContext(DeclContext *DC) {
1628   Record.AddOffset(Writer.WriteDeclContextLexicalBlock(Context, DC));
1629   Record.AddOffset(Writer.WriteDeclContextVisibleBlock(Context, DC));
1630 }
1631
1632 const Decl *ASTWriter::getFirstLocalDecl(const Decl *D) {
1633   assert(IsLocalDecl(D) && "expected a local declaration");
1634
1635   const Decl *Canon = D->getCanonicalDecl();
1636   if (IsLocalDecl(Canon))
1637     return Canon;
1638
1639   const Decl *&CacheEntry = FirstLocalDeclCache[Canon];
1640   if (CacheEntry)
1641     return CacheEntry;
1642
1643   for (const Decl *Redecl = D; Redecl; Redecl = Redecl->getPreviousDecl())
1644     if (IsLocalDecl(Redecl))
1645       D = Redecl;
1646   return CacheEntry = D;
1647 }
1648
1649 template <typename T>
1650 void ASTDeclWriter::VisitRedeclarable(Redeclarable<T> *D) {
1651   T *First = D->getFirstDecl();
1652   T *MostRecent = First->getMostRecentDecl();
1653   T *DAsT = static_cast<T *>(D);
1654   if (MostRecent != First) {
1655     assert(isRedeclarableDeclKind(DAsT->getKind()) &&
1656            "Not considered redeclarable?");
1657
1658     Record.AddDeclRef(First);
1659
1660     // Write out a list of local redeclarations of this declaration if it's the
1661     // first local declaration in the chain.
1662     const Decl *FirstLocal = Writer.getFirstLocalDecl(DAsT);
1663     if (DAsT == FirstLocal) {
1664       // Emit a list of all imported first declarations so that we can be sure
1665       // that all redeclarations visible to this module are before D in the
1666       // redecl chain.
1667       unsigned I = Record.size();
1668       Record.push_back(0);
1669       if (Writer.Chain)
1670         AddFirstDeclFromEachModule(DAsT, /*IncludeLocal*/false);
1671       // This is the number of imported first declarations + 1.
1672       Record[I] = Record.size() - I;
1673
1674       // Collect the set of local redeclarations of this declaration, from
1675       // newest to oldest.
1676       ASTWriter::RecordData LocalRedecls;
1677       ASTRecordWriter LocalRedeclWriter(Record, LocalRedecls);
1678       for (const Decl *Prev = FirstLocal->getMostRecentDecl();
1679            Prev != FirstLocal; Prev = Prev->getPreviousDecl())
1680         if (!Prev->isFromASTFile())
1681           LocalRedeclWriter.AddDeclRef(Prev);
1682
1683       // If we have any redecls, write them now as a separate record preceding
1684       // the declaration itself.
1685       if (LocalRedecls.empty())
1686         Record.push_back(0);
1687       else
1688         Record.AddOffset(LocalRedeclWriter.Emit(LOCAL_REDECLARATIONS));
1689     } else {
1690       Record.push_back(0);
1691       Record.AddDeclRef(FirstLocal);
1692     }
1693
1694     // Make sure that we serialize both the previous and the most-recent
1695     // declarations, which (transitively) ensures that all declarations in the
1696     // chain get serialized.
1697     //
1698     // FIXME: This is not correct; when we reach an imported declaration we
1699     // won't emit its previous declaration.
1700     (void)Writer.GetDeclRef(D->getPreviousDecl());
1701     (void)Writer.GetDeclRef(MostRecent);
1702   } else {
1703     // We use the sentinel value 0 to indicate an only declaration.
1704     Record.push_back(0);
1705   }
1706 }
1707
1708 void ASTDeclWriter::VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D) {
1709   Record.push_back(D->varlist_size());
1710   VisitDecl(D);
1711   for (auto *I : D->varlists())
1712     Record.AddStmt(I);
1713   Code = serialization::DECL_OMP_THREADPRIVATE;
1714 }
1715
1716 void ASTDeclWriter::VisitOMPDeclareReductionDecl(OMPDeclareReductionDecl *D) {
1717   VisitValueDecl(D);
1718   Record.AddSourceLocation(D->getLocStart());
1719   Record.AddStmt(D->getCombiner());
1720   Record.AddStmt(D->getInitializer());
1721   Record.push_back(D->getInitializerKind());
1722   Record.AddDeclRef(D->getPrevDeclInScope());
1723   Code = serialization::DECL_OMP_DECLARE_REDUCTION;
1724 }
1725
1726 void ASTDeclWriter::VisitOMPCapturedExprDecl(OMPCapturedExprDecl *D) {
1727   VisitVarDecl(D);
1728   Code = serialization::DECL_OMP_CAPTUREDEXPR;
1729 }
1730
1731 //===----------------------------------------------------------------------===//
1732 // ASTWriter Implementation
1733 //===----------------------------------------------------------------------===//
1734
1735 void ASTWriter::WriteDeclAbbrevs() {
1736   using namespace llvm;
1737
1738   std::shared_ptr<BitCodeAbbrev> Abv;
1739
1740   // Abbreviation for DECL_FIELD
1741   Abv = std::make_shared<BitCodeAbbrev>();
1742   Abv->Add(BitCodeAbbrevOp(serialization::DECL_FIELD));
1743   // Decl
1744   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1745   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1746   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1747   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1748   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1749   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1750   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1751   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1752   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1753   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1754   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1755   // NamedDecl
1756   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1757   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1758   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1759   // ValueDecl
1760   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1761   // DeclaratorDecl
1762   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1763   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1764   // FieldDecl
1765   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1766   Abv->Add(BitCodeAbbrevOp(0));                       // InitStyle
1767   // Type Source Info
1768   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1769   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1770   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1771   DeclFieldAbbrev = Stream.EmitAbbrev(std::move(Abv));
1772
1773   // Abbreviation for DECL_OBJC_IVAR
1774   Abv = std::make_shared<BitCodeAbbrev>();
1775   Abv->Add(BitCodeAbbrevOp(serialization::DECL_OBJC_IVAR));
1776   // Decl
1777   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1778   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1779   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1780   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1781   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1782   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1783   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1784   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1785   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2));  // AccessSpecifier
1786   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1787   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1788   // NamedDecl
1789   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1790   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1791   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1792   // ValueDecl
1793   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1794   // DeclaratorDecl
1795   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1796   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1797   // FieldDecl
1798   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isMutable
1799   Abv->Add(BitCodeAbbrevOp(0));                       // InitStyle
1800   // ObjC Ivar
1801   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getAccessControl
1802   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getSynthesize
1803   // Type Source Info
1804   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1805   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1806   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1807   DeclObjCIvarAbbrev = Stream.EmitAbbrev(std::move(Abv));
1808
1809   // Abbreviation for DECL_ENUM
1810   Abv = std::make_shared<BitCodeAbbrev>();
1811   Abv->Add(BitCodeAbbrevOp(serialization::DECL_ENUM));
1812   // Redeclarable
1813   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1814   // Decl
1815   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1816   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1817   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1818   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1819   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1820   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1821   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1822   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1823   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1824   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1825   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1826   // NamedDecl
1827   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1828   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1829   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1830   // TypeDecl
1831   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1832   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1833   // TagDecl
1834   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1835   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1836   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1837   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1838   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1839   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsCompleteDefinitionRequired
1840   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1841   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1842   Abv->Add(BitCodeAbbrevOp(0));                         // ExtInfoKind
1843   // EnumDecl
1844   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddTypeRef
1845   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IntegerType
1846   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getPromotionType
1847   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumPositiveBits
1848   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getNumNegativeBits
1849   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScoped
1850   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isScopedUsingClassTag
1851   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isFixed
1852   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InstantiatedMembEnum
1853   // DC
1854   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1855   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1856   DeclEnumAbbrev = Stream.EmitAbbrev(std::move(Abv));
1857
1858   // Abbreviation for DECL_RECORD
1859   Abv = std::make_shared<BitCodeAbbrev>();
1860   Abv->Add(BitCodeAbbrevOp(serialization::DECL_RECORD));
1861   // Redeclarable
1862   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1863   // Decl
1864   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1865   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1866   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1867   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1868   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1869   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1870   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1871   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1872   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1873   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1874   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1875   // NamedDecl
1876   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1877   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1878   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1879   // TypeDecl
1880   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1881   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1882   // TagDecl
1883   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // IdentifierNamespace
1884   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // getTagKind
1885   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCompleteDefinition
1886   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // EmbeddedInDeclarator
1887   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFreeStanding
1888   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsCompleteDefinitionRequired
1889   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1890   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SourceLocation
1891   Abv->Add(BitCodeAbbrevOp(0));                         // ExtInfoKind
1892   // RecordDecl
1893   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // FlexibleArrayMember
1894   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // AnonymousStructUnion
1895   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasObjectMember
1896   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // hasVolatileMember
1897   // DC
1898   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LexicalOffset
1899   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // VisibleOffset
1900   DeclRecordAbbrev = Stream.EmitAbbrev(std::move(Abv));
1901
1902   // Abbreviation for DECL_PARM_VAR
1903   Abv = std::make_shared<BitCodeAbbrev>();
1904   Abv->Add(BitCodeAbbrevOp(serialization::DECL_PARM_VAR));
1905   // Redeclarable
1906   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1907   // Decl
1908   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1909   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1910   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1911   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1912   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1913   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1914   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1915   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1916   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1917   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1918   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1919   // NamedDecl
1920   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1921   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1922   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1923   // ValueDecl
1924   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
1925   // DeclaratorDecl
1926   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
1927   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
1928   // VarDecl
1929   Abv->Add(BitCodeAbbrevOp(0));                       // SClass
1930   Abv->Add(BitCodeAbbrevOp(0));                       // TSCSpec
1931   Abv->Add(BitCodeAbbrevOp(0));                       // InitStyle
1932   Abv->Add(BitCodeAbbrevOp(0));                       // Linkage
1933   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
1934   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
1935   // ParmVarDecl
1936   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsObjCMethodParameter
1937   Abv->Add(BitCodeAbbrevOp(0));                       // ScopeDepth
1938   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ScopeIndex
1939   Abv->Add(BitCodeAbbrevOp(0));                       // ObjCDeclQualifier
1940   Abv->Add(BitCodeAbbrevOp(0));                       // KNRPromoted
1941   Abv->Add(BitCodeAbbrevOp(0));                       // HasInheritedDefaultArg
1942   Abv->Add(BitCodeAbbrevOp(0));                   // HasUninstantiatedDefaultArg
1943   // Type Source Info
1944   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1945   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1946   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1947   DeclParmVarAbbrev = Stream.EmitAbbrev(std::move(Abv));
1948
1949   // Abbreviation for DECL_TYPEDEF
1950   Abv = std::make_shared<BitCodeAbbrev>();
1951   Abv->Add(BitCodeAbbrevOp(serialization::DECL_TYPEDEF));
1952   // Redeclarable
1953   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1954   // Decl
1955   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1956   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1957   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1958   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1959   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1960   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isUsed
1961   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isReferenced
1962   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1963   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // C++ AccessSpecifier
1964   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1965   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1966   // NamedDecl
1967   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1968   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1969   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1970   // TypeDecl
1971   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
1972   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type Ref
1973   // TypedefDecl
1974   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1975   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
1976   DeclTypedefAbbrev = Stream.EmitAbbrev(std::move(Abv));
1977
1978   // Abbreviation for DECL_VAR
1979   Abv = std::make_shared<BitCodeAbbrev>();
1980   Abv->Add(BitCodeAbbrevOp(serialization::DECL_VAR));
1981   // Redeclarable
1982   Abv->Add(BitCodeAbbrevOp(0));                       // No redeclaration
1983   // Decl
1984   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclContext
1985   Abv->Add(BitCodeAbbrevOp(0));                       // LexicalDeclContext
1986   Abv->Add(BitCodeAbbrevOp(0));                       // isInvalidDecl
1987   Abv->Add(BitCodeAbbrevOp(0));                       // HasAttrs
1988   Abv->Add(BitCodeAbbrevOp(0));                       // isImplicit
1989   Abv->Add(BitCodeAbbrevOp(0));                       // isUsed
1990   Abv->Add(BitCodeAbbrevOp(0));                       // isReferenced
1991   Abv->Add(BitCodeAbbrevOp(0));                   // TopLevelDeclInObjCContainer
1992   Abv->Add(BitCodeAbbrevOp(AS_none));                 // C++ AccessSpecifier
1993   Abv->Add(BitCodeAbbrevOp(0));                       // ModulePrivate
1994   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // SubmoduleID
1995   // NamedDecl
1996   Abv->Add(BitCodeAbbrevOp(0));                       // NameKind = Identifier
1997   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Name
1998   Abv->Add(BitCodeAbbrevOp(0));                       // AnonDeclNumber
1999   // ValueDecl
2000   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2001   // DeclaratorDecl
2002   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
2003   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
2004   // VarDecl
2005   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // SClass
2006   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // TSCSpec
2007   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // InitStyle
2008   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsThisDeclarationADemotedDefinition
2009   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
2010   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
2011   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
2012   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
2013   Abv->Add(BitCodeAbbrevOp(0));                         // isInline
2014   Abv->Add(BitCodeAbbrevOp(0));                         // isInlineSpecified
2015   Abv->Add(BitCodeAbbrevOp(0));                         // isConstexpr
2016   Abv->Add(BitCodeAbbrevOp(0));                         // isInitCapture
2017   Abv->Add(BitCodeAbbrevOp(0));                         // isPrevDeclInSameScope
2018   Abv->Add(BitCodeAbbrevOp(0));                         // ImplicitParamKind
2019   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Linkage
2020   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // IsInitICE (local)
2021   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // VarKind (local enum)
2022   // Type Source Info
2023   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
2024   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2025   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // TypeLoc
2026   DeclVarAbbrev = Stream.EmitAbbrev(std::move(Abv));
2027
2028   // Abbreviation for DECL_CXX_METHOD
2029   Abv = std::make_shared<BitCodeAbbrev>();
2030   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CXX_METHOD));
2031   // RedeclarableDecl
2032   Abv->Add(BitCodeAbbrevOp(0));                         // CanonicalDecl
2033   // Decl
2034   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // DeclContext
2035   Abv->Add(BitCodeAbbrevOp(0));                         // LexicalDeclContext
2036   Abv->Add(BitCodeAbbrevOp(0));                         // Invalid
2037   Abv->Add(BitCodeAbbrevOp(0));                         // HasAttrs
2038   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Implicit
2039   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Used
2040   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Referenced
2041   Abv->Add(BitCodeAbbrevOp(0));                         // InObjCContainer
2042   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // Access
2043   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ModulePrivate
2044   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // SubmoduleID
2045   // NamedDecl
2046   Abv->Add(BitCodeAbbrevOp(DeclarationName::Identifier)); // NameKind
2047   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Identifier
2048   Abv->Add(BitCodeAbbrevOp(0));                         // AnonDeclNumber
2049   // ValueDecl
2050   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Type
2051   // DeclaratorDecl
2052   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // InnerLocStart
2053   Abv->Add(BitCodeAbbrevOp(0));                         // HasExtInfo
2054   // FunctionDecl
2055   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 11)); // IDNS
2056   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // StorageClass
2057   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Inline
2058   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InlineSpecified
2059   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ExplicitSpecified
2060   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // VirtualAsWritten
2061   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Pure
2062   Abv->Add(BitCodeAbbrevOp(0));                         // HasInheritedProto
2063   Abv->Add(BitCodeAbbrevOp(1));                         // HasWrittenProto
2064   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Deleted
2065   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Trivial
2066   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Defaulted
2067   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ExplicitlyDefaulted
2068   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ImplicitReturnZero
2069   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Constexpr
2070   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // UsesSEHTry
2071   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // SkippedBody
2072   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // LateParsed
2073   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Linkage
2074   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LocEnd
2075   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // TemplateKind
2076   // This Array slurps the rest of the record. Fortunately we want to encode
2077   // (nearly) all the remaining (variable number of) fields in the same way.
2078   //
2079   // This is the function template information if any, then
2080   //         NumParams and Params[] from FunctionDecl, and
2081   //         NumOverriddenMethods, OverriddenMethods[] from CXXMethodDecl.
2082   //
2083   //  Add an AbbrevOp for 'size then elements' and use it here.
2084   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2085   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
2086   DeclCXXMethodAbbrev = Stream.EmitAbbrev(std::move(Abv));
2087
2088   // Abbreviation for EXPR_DECL_REF
2089   Abv = std::make_shared<BitCodeAbbrev>();
2090   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_DECL_REF));
2091   //Stmt
2092   //Expr
2093   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2094   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
2095   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
2096   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
2097   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
2098   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
2099   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
2100   //DeclRefExpr
2101   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HasQualifier
2102   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //GetDeclFound
2103   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ExplicitTemplateArgs
2104   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //HadMultipleCandidates
2105   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
2106                            1)); // RefersToEnclosingVariableOrCapture
2107   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // DeclRef
2108   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
2109   DeclRefExprAbbrev = Stream.EmitAbbrev(std::move(Abv));
2110
2111   // Abbreviation for EXPR_INTEGER_LITERAL
2112   Abv = std::make_shared<BitCodeAbbrev>();
2113   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_INTEGER_LITERAL));
2114   //Stmt
2115   //Expr
2116   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2117   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
2118   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
2119   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
2120   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
2121   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
2122   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
2123   //Integer Literal
2124   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
2125   Abv->Add(BitCodeAbbrevOp(32));                      // Bit Width
2126   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Value
2127   IntegerLiteralAbbrev = Stream.EmitAbbrev(std::move(Abv));
2128
2129   // Abbreviation for EXPR_CHARACTER_LITERAL
2130   Abv = std::make_shared<BitCodeAbbrev>();
2131   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_CHARACTER_LITERAL));
2132   //Stmt
2133   //Expr
2134   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2135   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
2136   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
2137   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
2138   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
2139   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
2140   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
2141   //Character Literal
2142   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // getValue
2143   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Location
2144   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // getKind
2145   CharacterLiteralAbbrev = Stream.EmitAbbrev(std::move(Abv));
2146
2147   // Abbreviation for EXPR_IMPLICIT_CAST
2148   Abv = std::make_shared<BitCodeAbbrev>();
2149   Abv->Add(BitCodeAbbrevOp(serialization::EXPR_IMPLICIT_CAST));
2150   // Stmt
2151   // Expr
2152   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Type
2153   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //TypeDependent
2154   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //ValueDependent
2155   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //InstantiationDependent
2156   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); //UnexpandedParamPack
2157   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetValueKind
2158   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); //GetObjectKind
2159   // CastExpr
2160   Abv->Add(BitCodeAbbrevOp(0)); // PathSize
2161   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 6)); // CastKind
2162   // ImplicitCastExpr
2163   ExprImplicitCastAbbrev = Stream.EmitAbbrev(std::move(Abv));
2164
2165   Abv = std::make_shared<BitCodeAbbrev>();
2166   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_LEXICAL));
2167   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2168   DeclContextLexicalAbbrev = Stream.EmitAbbrev(std::move(Abv));
2169
2170   Abv = std::make_shared<BitCodeAbbrev>();
2171   Abv->Add(BitCodeAbbrevOp(serialization::DECL_CONTEXT_VISIBLE));
2172   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2173   DeclContextVisibleLookupAbbrev = Stream.EmitAbbrev(std::move(Abv));
2174 }
2175
2176 /// isRequiredDecl - Check if this is a "required" Decl, which must be seen by
2177 /// consumers of the AST.
2178 ///
2179 /// Such decls will always be deserialized from the AST file, so we would like
2180 /// this to be as restrictive as possible. Currently the predicate is driven by
2181 /// code generation requirements, if other clients have a different notion of
2182 /// what is "required" then we may have to consider an alternate scheme where
2183 /// clients can iterate over the top-level decls and get information on them,
2184 /// without necessary deserializing them. We could explicitly require such
2185 /// clients to use a separate API call to "realize" the decl. This should be
2186 /// relatively painless since they would presumably only do it for top-level
2187 /// decls.
2188 static bool isRequiredDecl(const Decl *D, ASTContext &Context,
2189                            bool WritingModule) {
2190   // An ObjCMethodDecl is never considered as "required" because its
2191   // implementation container always is.
2192
2193   // File scoped assembly or obj-c or OMP declare target implementation must be
2194   // seen.
2195   if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplDecl>(D) ||
2196       D->hasAttr<OMPDeclareTargetDeclAttr>())
2197     return true;
2198
2199   if (WritingModule && (isa<VarDecl>(D) || isa<ImportDecl>(D))) {
2200     // These declarations are part of the module initializer, and are emitted
2201     // if and when the module is imported, rather than being emitted eagerly.
2202     return false;
2203   }
2204
2205   return Context.DeclMustBeEmitted(D);
2206 }
2207
2208 void ASTWriter::WriteDecl(ASTContext &Context, Decl *D) {
2209   // Determine the ID for this declaration.
2210   serialization::DeclID ID;
2211   assert(!D->isFromASTFile() && "should not be emitting imported decl");
2212   serialization::DeclID &IDR = DeclIDs[D];
2213   if (IDR == 0)
2214     IDR = NextDeclID++;
2215
2216   ID = IDR;
2217
2218   assert(ID >= FirstDeclID && "invalid decl ID");
2219
2220   RecordData Record;
2221   ASTDeclWriter W(*this, Context, Record);
2222
2223   // Build a record for this declaration
2224   W.Visit(D);
2225
2226   // Emit this declaration to the bitstream.
2227   uint64_t Offset = W.Emit(D);
2228
2229   // Record the offset for this declaration
2230   SourceLocation Loc = D->getLocation();
2231   unsigned Index = ID - FirstDeclID;
2232   if (DeclOffsets.size() == Index)
2233     DeclOffsets.push_back(DeclOffset(Loc, Offset));
2234   else if (DeclOffsets.size() < Index) {
2235     // FIXME: Can/should this happen?
2236     DeclOffsets.resize(Index+1);
2237     DeclOffsets[Index].setLocation(Loc);
2238     DeclOffsets[Index].BitOffset = Offset;
2239   } else {
2240     llvm_unreachable("declarations should be emitted in ID order");
2241   }
2242
2243   SourceManager &SM = Context.getSourceManager();
2244   if (Loc.isValid() && SM.isLocalSourceLocation(Loc))
2245     associateDeclWithFile(D, ID);
2246
2247   // Note declarations that should be deserialized eagerly so that we can add
2248   // them to a record in the AST file later.
2249   if (isRequiredDecl(D, Context, WritingModule))
2250     EagerlyDeserializedDecls.push_back(ID);
2251 }
2252
2253 void ASTRecordWriter::AddFunctionDefinition(const FunctionDecl *FD) {
2254   // Switch case IDs are per function body.
2255   Writer->ClearSwitchCaseIDs();
2256
2257   assert(FD->doesThisDeclarationHaveABody());
2258   bool ModulesCodegen = false;
2259   if (Writer->WritingModule && !FD->isDependentContext()) {
2260     Optional<GVALinkage> Linkage;
2261     if (Writer->WritingModule->Kind == Module::ModuleInterfaceUnit) {
2262       // When building a C++ Modules TS module interface unit, a strong
2263       // definition in the module interface is provided by the compilation of
2264       // that module interface unit, not by its users. (Inline functions are
2265       // still emitted in module users.)
2266       Linkage = Writer->Context->GetGVALinkageForFunction(FD);
2267       ModulesCodegen = *Linkage == GVA_StrongExternal;
2268     }
2269     if (Writer->Context->getLangOpts().ModulesCodegen) {
2270       // Under -fmodules-codegen, codegen is performed for all non-internal,
2271       // non-always_inline functions.
2272       if (!FD->hasAttr<AlwaysInlineAttr>()) {
2273         if (!Linkage)
2274           Linkage = Writer->Context->GetGVALinkageForFunction(FD);
2275         ModulesCodegen = *Linkage != GVA_Internal;
2276       }
2277     }
2278   }
2279   Record->push_back(ModulesCodegen);
2280   if (ModulesCodegen)
2281     Writer->ModularCodegenDecls.push_back(Writer->GetDeclRef(FD));
2282   if (auto *CD = dyn_cast<CXXConstructorDecl>(FD)) {
2283     Record->push_back(CD->getNumCtorInitializers());
2284     if (CD->getNumCtorInitializers())
2285       AddCXXCtorInitializers(
2286           llvm::makeArrayRef(CD->init_begin(), CD->init_end()));
2287   }
2288   AddStmt(FD->getBody());
2289 }