clang/lib/Serialization/ASTWriter.cpp

   1 //===- ASTWriter.cpp - AST File Writer ------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 //  This file defines the ASTWriter class, which writes AST files.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "ASTCommon.h"
  14 #include "ASTReaderInternals.h"
  15 #include "MultiOnDiskHashTable.h"
  16 #include "clang/AST/ASTContext.h"
  17 #include "clang/AST/ASTUnresolvedSet.h"
  18 #include "clang/AST/AbstractTypeWriter.h"
  19 #include "clang/AST/Attr.h"
  20 #include "clang/AST/Decl.h"
  21 #include "clang/AST/DeclBase.h"
  22 #include "clang/AST/DeclCXX.h"
  23 #include "clang/AST/DeclContextInternals.h"
  24 #include "clang/AST/DeclFriend.h"
  25 #include "clang/AST/DeclObjC.h"
  26 #include "clang/AST/DeclTemplate.h"
  27 #include "clang/AST/DeclarationName.h"
  28 #include "clang/AST/Expr.h"
  29 #include "clang/AST/ExprCXX.h"
  30 #include "clang/AST/LambdaCapture.h"
  31 #include "clang/AST/NestedNameSpecifier.h"
  32 #include "clang/AST/OpenMPClause.h"
  33 #include "clang/AST/RawCommentList.h"
  34 #include "clang/AST/TemplateName.h"
  35 #include "clang/AST/Type.h"
  36 #include "clang/AST/TypeLocVisitor.h"
  37 #include "clang/Basic/Diagnostic.h"
  38 #include "clang/Basic/DiagnosticOptions.h"
  39 #include "clang/Basic/FileManager.h"
  40 #include "clang/Basic/FileSystemOptions.h"
  41 #include "clang/Basic/IdentifierTable.h"
  42 #include "clang/Basic/LLVM.h"
  43 #include "clang/Basic/Lambda.h"
  44 #include "clang/Basic/LangOptions.h"
  45 #include "clang/Basic/Module.h"
  46 #include "clang/Basic/ObjCRuntime.h"
  47 #include "clang/Basic/OpenCLOptions.h"
  48 #include "clang/Basic/SourceLocation.h"
  49 #include "clang/Basic/SourceManager.h"
  50 #include "clang/Basic/SourceManagerInternals.h"
  51 #include "clang/Basic/Specifiers.h"
  52 #include "clang/Basic/TargetInfo.h"
  53 #include "clang/Basic/TargetOptions.h"
  54 #include "clang/Basic/Version.h"
  55 #include "clang/Lex/HeaderSearch.h"
  56 #include "clang/Lex/HeaderSearchOptions.h"
  57 #include "clang/Lex/MacroInfo.h"
  58 #include "clang/Lex/ModuleMap.h"
  59 #include "clang/Lex/PreprocessingRecord.h"
  60 #include "clang/Lex/Preprocessor.h"
  61 #include "clang/Lex/PreprocessorOptions.h"
  62 #include "clang/Lex/Token.h"
  63 #include "clang/Sema/IdentifierResolver.h"
  64 #include "clang/Sema/ObjCMethodList.h"
  65 #include "clang/Sema/Sema.h"
  66 #include "clang/Sema/Weak.h"
  67 #include "clang/Serialization/ASTBitCodes.h"
  68 #include "clang/Serialization/ASTReader.h"
  69 #include "clang/Serialization/ASTRecordWriter.h"
  70 #include "clang/Serialization/InMemoryModuleCache.h"
  71 #include "clang/Serialization/ModuleFile.h"
  72 #include "clang/Serialization/ModuleFileExtension.h"
  73 #include "clang/Serialization/SerializationDiagnostic.h"
  74 #include "llvm/ADT/APFloat.h"
  75 #include "llvm/ADT/APInt.h"
  76 #include "llvm/ADT/APSInt.h"
  77 #include "llvm/ADT/ArrayRef.h"
  78 #include "llvm/ADT/DenseMap.h"
  79 #include "llvm/ADT/Hashing.h"
  80 #include "llvm/ADT/Optional.h"
  81 #include "llvm/ADT/PointerIntPair.h"
  82 #include "llvm/ADT/STLExtras.h"
  83 #include "llvm/ADT/ScopeExit.h"
  84 #include "llvm/ADT/SmallPtrSet.h"
  85 #include "llvm/ADT/SmallString.h"
  86 #include "llvm/ADT/SmallVector.h"
  87 #include "llvm/ADT/StringMap.h"
  88 #include "llvm/ADT/StringRef.h"
  89 #include "llvm/Bitstream/BitCodes.h"
  90 #include "llvm/Bitstream/BitstreamWriter.h"
  91 #include "llvm/Support/Casting.h"
  92 #include "llvm/Support/Compression.h"
  93 #include "llvm/Support/DJB.h"
  94 #include "llvm/Support/Endian.h"
  95 #include "llvm/Support/EndianStream.h"
  96 #include "llvm/Support/Error.h"
  97 #include "llvm/Support/ErrorHandling.h"
  98 #include "llvm/Support/LEB128.h"
  99 #include "llvm/Support/MemoryBuffer.h"
 100 #include "llvm/Support/OnDiskHashTable.h"
 101 #include "llvm/Support/Path.h"
 102 #include "llvm/Support/SHA1.h"
 103 #include "llvm/Support/VersionTuple.h"
 104 #include "llvm/Support/raw_ostream.h"
 105 #include <algorithm>
 106 #include <cassert>
 107 #include <cstdint>
 108 #include <cstdlib>
 109 #include <cstring>
 110 #include <ctime>
 111 #include <deque>
 112 #include <limits>
 113 #include <memory>
 114 #include <queue>
 115 #include <tuple>
 116 #include <utility>
 117 #include <vector>
 118
 119 using namespace clang;
 120 using namespace clang::serialization;
 121
 122 template <typename T, typename Allocator>
 123 static StringRef bytes(const std::vector<T, Allocator> &v) {
 124   if (v.empty()) return StringRef();
 125   return StringRef(reinterpret_cast<const char*>(&v[0]),
 126                          sizeof(T) * v.size());
 127 }
 128
 129 template <typename T>
 130 static StringRef bytes(const SmallVectorImpl<T> &v) {
 131   return StringRef(reinterpret_cast<const char*>(v.data()),
 132                          sizeof(T) * v.size());
 133 }
 134
 135 static std::string bytes(const std::vector<bool> &V) {
 136   std::string Str;
 137   Str.reserve(V.size() / 8);
 138   for (unsigned I = 0, E = V.size(); I < E;) {
 139     char Byte = 0;
 140     for (unsigned Bit = 0; Bit < 8 && I < E; ++Bit, ++I)
 141       Byte |= V[I] << Bit;
 142     Str += Byte;
 143   }
 144   return Str;
 145 }
 146
 147 //===----------------------------------------------------------------------===//
 148 // Type serialization
 149 //===----------------------------------------------------------------------===//
 150
 151 static TypeCode getTypeCodeForTypeClass(Type::TypeClass id) {
 152   switch (id) {
 153 #define TYPE_BIT_CODE(CLASS_ID, CODE_ID, CODE_VALUE) \
 154   case Type::CLASS_ID: return TYPE_##CODE_ID;
 155 #include "clang/Serialization/TypeBitCodes.def"
 156   case Type::Builtin:
 157     llvm_unreachable("shouldn't be serializing a builtin type this way");
 158   }
 159   llvm_unreachable("bad type kind");
 160 }
 161
 162 namespace {
 163
 164 std::set<const FileEntry *> GetAllModuleMaps(const HeaderSearch &HS,
 165                                              Module *RootModule) {
 166   std::set<const FileEntry *> ModuleMaps{};
 167   std::set<const Module *> ProcessedModules;
 168   SmallVector<const Module *> ModulesToProcess{RootModule};
 169
 170   SmallVector<const FileEntry *, 16> FilesByUID;
 171   HS.getFileMgr().GetUniqueIDMapping(FilesByUID);
 172
 173   if (FilesByUID.size() > HS.header_file_size())
 174     FilesByUID.resize(HS.header_file_size());
 175
 176   for (unsigned UID = 0, LastUID = FilesByUID.size(); UID != LastUID; ++UID) {
 177     const FileEntry *File = FilesByUID[UID];
 178     if (!File)
 179       continue;
 180
 181     const HeaderFileInfo *HFI =
 182         HS.getExistingFileInfo(File, /*WantExternal*/ false);
 183     if (!HFI || (HFI->isModuleHeader && !HFI->isCompilingModuleHeader))
 184       continue;
 185
 186     for (const auto &KH : HS.findAllModulesForHeader(File)) {
 187       if (!KH.getModule())
 188         continue;
 189       ModulesToProcess.push_back(KH.getModule());
 190     }
 191   }
 192
 193   while (!ModulesToProcess.empty()) {
 194     auto *CurrentModule = ModulesToProcess.pop_back_val();
 195     ProcessedModules.insert(CurrentModule);
 196
 197     auto *ModuleMapFile =
 198         HS.getModuleMap().getModuleMapFileForUniquing(CurrentModule);
 199     if (!ModuleMapFile) {
 200       continue;
 201     }
 202
 203     ModuleMaps.insert(ModuleMapFile);
 204
 205     for (auto *ImportedModule : (CurrentModule)->Imports) {
 206       if (!ImportedModule ||
 207           ProcessedModules.find(ImportedModule) != ProcessedModules.end()) {
 208         continue;
 209       }
 210       ModulesToProcess.push_back(ImportedModule);
 211     }
 212
 213     for (const Module *UndeclaredModule : CurrentModule->UndeclaredUses)
 214       if (UndeclaredModule &&
 215           ProcessedModules.find(UndeclaredModule) == ProcessedModules.end())
 216         ModulesToProcess.push_back(UndeclaredModule);
 217   }
 218
 219   return ModuleMaps;
 220 }
 221
 222 class ASTTypeWriter {
 223   ASTWriter &Writer;
 224   ASTWriter::RecordData Record;
 225   ASTRecordWriter BasicWriter;
 226
 227 public:
 228   ASTTypeWriter(ASTWriter &Writer)
 229     : Writer(Writer), BasicWriter(Writer, Record) {}
 230
 231   uint64_t write(QualType T) {
 232     if (T.hasLocalNonFastQualifiers()) {
 233       Qualifiers Qs = T.getLocalQualifiers();
 234       BasicWriter.writeQualType(T.getLocalUnqualifiedType());
 235       BasicWriter.writeQualifiers(Qs);
 236       return BasicWriter.Emit(TYPE_EXT_QUAL, Writer.getTypeExtQualAbbrev());
 237     }
 238
 239     const Type *typePtr = T.getTypePtr();
 240     serialization::AbstractTypeWriter<ASTRecordWriter> atw(BasicWriter);
 241     atw.write(typePtr);
 242     return BasicWriter.Emit(getTypeCodeForTypeClass(typePtr->getTypeClass()),
 243                             /*abbrev*/ 0);
 244   }
 245 };
 246
 247 class TypeLocWriter : public TypeLocVisitor<TypeLocWriter> {
 248   using LocSeq = SourceLocationSequence;
 249
 250   ASTRecordWriter &Record;
 251   LocSeq *Seq;
 252
 253   void addSourceLocation(SourceLocation Loc) {
 254     Record.AddSourceLocation(Loc, Seq);
 255   }
 256   void addSourceRange(SourceRange Range) { Record.AddSourceRange(Range, Seq); }
 257
 258 public:
 259   TypeLocWriter(ASTRecordWriter &Record, LocSeq *Seq)
 260       : Record(Record), Seq(Seq) {}
 261
 262 #define ABSTRACT_TYPELOC(CLASS, PARENT)
 263 #define TYPELOC(CLASS, PARENT) \
 264     void Visit##CLASS##TypeLoc(CLASS##TypeLoc TyLoc);
 265 #include "clang/AST/TypeLocNodes.def"
 266
 267   void VisitArrayTypeLoc(ArrayTypeLoc TyLoc);
 268   void VisitFunctionTypeLoc(FunctionTypeLoc TyLoc);
 269 };
 270
 271 } // namespace
 272
 273 void TypeLocWriter::VisitQualifiedTypeLoc(QualifiedTypeLoc TL) {
 274   // nothing to do
 275 }
 276
 277 void TypeLocWriter::VisitBuiltinTypeLoc(BuiltinTypeLoc TL) {
 278   addSourceLocation(TL.getBuiltinLoc());
 279   if (TL.needsExtraLocalData()) {
 280     Record.push_back(TL.getWrittenTypeSpec());
 281     Record.push_back(static_cast<uint64_t>(TL.getWrittenSignSpec()));
 282     Record.push_back(static_cast<uint64_t>(TL.getWrittenWidthSpec()));
 283     Record.push_back(TL.hasModeAttr());
 284   }
 285 }
 286
 287 void TypeLocWriter::VisitComplexTypeLoc(ComplexTypeLoc TL) {
 288   addSourceLocation(TL.getNameLoc());
 289 }
 290
 291 void TypeLocWriter::VisitPointerTypeLoc(PointerTypeLoc TL) {
 292   addSourceLocation(TL.getStarLoc());
 293 }
 294
 295 void TypeLocWriter::VisitDecayedTypeLoc(DecayedTypeLoc TL) {
 296   // nothing to do
 297 }
 298
 299 void TypeLocWriter::VisitAdjustedTypeLoc(AdjustedTypeLoc TL) {
 300   // nothing to do
 301 }
 302
 303 void TypeLocWriter::VisitBlockPointerTypeLoc(BlockPointerTypeLoc TL) {
 304   addSourceLocation(TL.getCaretLoc());
 305 }
 306
 307 void TypeLocWriter::VisitLValueReferenceTypeLoc(LValueReferenceTypeLoc TL) {
 308   addSourceLocation(TL.getAmpLoc());
 309 }
 310
 311 void TypeLocWriter::VisitRValueReferenceTypeLoc(RValueReferenceTypeLoc TL) {
 312   addSourceLocation(TL.getAmpAmpLoc());
 313 }
 314
 315 void TypeLocWriter::VisitMemberPointerTypeLoc(MemberPointerTypeLoc TL) {
 316   addSourceLocation(TL.getStarLoc());
 317   Record.AddTypeSourceInfo(TL.getClassTInfo());
 318 }
 319
 320 void TypeLocWriter::VisitArrayTypeLoc(ArrayTypeLoc TL) {
 321   addSourceLocation(TL.getLBracketLoc());
 322   addSourceLocation(TL.getRBracketLoc());
 323   Record.push_back(TL.getSizeExpr() ? 1 : 0);
 324   if (TL.getSizeExpr())
 325     Record.AddStmt(TL.getSizeExpr());
 326 }
 327
 328 void TypeLocWriter::VisitConstantArrayTypeLoc(ConstantArrayTypeLoc TL) {
 329   VisitArrayTypeLoc(TL);
 330 }
 331
 332 void TypeLocWriter::VisitIncompleteArrayTypeLoc(IncompleteArrayTypeLoc TL) {
 333   VisitArrayTypeLoc(TL);
 334 }
 335
 336 void TypeLocWriter::VisitVariableArrayTypeLoc(VariableArrayTypeLoc TL) {
 337   VisitArrayTypeLoc(TL);
 338 }
 339
 340 void TypeLocWriter::VisitDependentSizedArrayTypeLoc(
 341                                             DependentSizedArrayTypeLoc TL) {
 342   VisitArrayTypeLoc(TL);
 343 }
 344
 345 void TypeLocWriter::VisitDependentAddressSpaceTypeLoc(
 346     DependentAddressSpaceTypeLoc TL) {
 347   addSourceLocation(TL.getAttrNameLoc());
 348   SourceRange range = TL.getAttrOperandParensRange();
 349   addSourceLocation(range.getBegin());
 350   addSourceLocation(range.getEnd());
 351   Record.AddStmt(TL.getAttrExprOperand());
 352 }
 353
 354 void TypeLocWriter::VisitDependentSizedExtVectorTypeLoc(
 355                                         DependentSizedExtVectorTypeLoc TL) {
 356   addSourceLocation(TL.getNameLoc());
 357 }
 358
 359 void TypeLocWriter::VisitVectorTypeLoc(VectorTypeLoc TL) {
 360   addSourceLocation(TL.getNameLoc());
 361 }
 362
 363 void TypeLocWriter::VisitDependentVectorTypeLoc(
 364     DependentVectorTypeLoc TL) {
 365   addSourceLocation(TL.getNameLoc());
 366 }
 367
 368 void TypeLocWriter::VisitExtVectorTypeLoc(ExtVectorTypeLoc TL) {
 369   addSourceLocation(TL.getNameLoc());
 370 }
 371
 372 void TypeLocWriter::VisitConstantMatrixTypeLoc(ConstantMatrixTypeLoc TL) {
 373   addSourceLocation(TL.getAttrNameLoc());
 374   SourceRange range = TL.getAttrOperandParensRange();
 375   addSourceLocation(range.getBegin());
 376   addSourceLocation(range.getEnd());
 377   Record.AddStmt(TL.getAttrRowOperand());
 378   Record.AddStmt(TL.getAttrColumnOperand());
 379 }
 380
 381 void TypeLocWriter::VisitDependentSizedMatrixTypeLoc(
 382     DependentSizedMatrixTypeLoc TL) {
 383   addSourceLocation(TL.getAttrNameLoc());
 384   SourceRange range = TL.getAttrOperandParensRange();
 385   addSourceLocation(range.getBegin());
 386   addSourceLocation(range.getEnd());
 387   Record.AddStmt(TL.getAttrRowOperand());
 388   Record.AddStmt(TL.getAttrColumnOperand());
 389 }
 390
 391 void TypeLocWriter::VisitFunctionTypeLoc(FunctionTypeLoc TL) {
 392   addSourceLocation(TL.getLocalRangeBegin());
 393   addSourceLocation(TL.getLParenLoc());
 394   addSourceLocation(TL.getRParenLoc());
 395   addSourceRange(TL.getExceptionSpecRange());
 396   addSourceLocation(TL.getLocalRangeEnd());
 397   for (unsigned i = 0, e = TL.getNumParams(); i != e; ++i)
 398     Record.AddDeclRef(TL.getParam(i));
 399 }
 400
 401 void TypeLocWriter::VisitFunctionProtoTypeLoc(FunctionProtoTypeLoc TL) {
 402   VisitFunctionTypeLoc(TL);
 403 }
 404
 405 void TypeLocWriter::VisitFunctionNoProtoTypeLoc(FunctionNoProtoTypeLoc TL) {
 406   VisitFunctionTypeLoc(TL);
 407 }
 408
 409 void TypeLocWriter::VisitUnresolvedUsingTypeLoc(UnresolvedUsingTypeLoc TL) {
 410   addSourceLocation(TL.getNameLoc());
 411 }
 412
 413 void TypeLocWriter::VisitUsingTypeLoc(UsingTypeLoc TL) {
 414   addSourceLocation(TL.getNameLoc());
 415 }
 416
 417 void TypeLocWriter::VisitTypedefTypeLoc(TypedefTypeLoc TL) {
 418   addSourceLocation(TL.getNameLoc());
 419 }
 420
 421 void TypeLocWriter::VisitObjCTypeParamTypeLoc(ObjCTypeParamTypeLoc TL) {
 422   if (TL.getNumProtocols()) {
 423     addSourceLocation(TL.getProtocolLAngleLoc());
 424     addSourceLocation(TL.getProtocolRAngleLoc());
 425   }
 426   for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
 427     addSourceLocation(TL.getProtocolLoc(i));
 428 }
 429
 430 void TypeLocWriter::VisitTypeOfExprTypeLoc(TypeOfExprTypeLoc TL) {
 431   addSourceLocation(TL.getTypeofLoc());
 432   addSourceLocation(TL.getLParenLoc());
 433   addSourceLocation(TL.getRParenLoc());
 434 }
 435
 436 void TypeLocWriter::VisitTypeOfTypeLoc(TypeOfTypeLoc TL) {
 437   addSourceLocation(TL.getTypeofLoc());
 438   addSourceLocation(TL.getLParenLoc());
 439   addSourceLocation(TL.getRParenLoc());
 440   Record.AddTypeSourceInfo(TL.getUnderlyingTInfo());
 441 }
 442
 443 void TypeLocWriter::VisitDecltypeTypeLoc(DecltypeTypeLoc TL) {
 444   addSourceLocation(TL.getDecltypeLoc());
 445   addSourceLocation(TL.getRParenLoc());
 446 }
 447
 448 void TypeLocWriter::VisitUnaryTransformTypeLoc(UnaryTransformTypeLoc TL) {
 449   addSourceLocation(TL.getKWLoc());
 450   addSourceLocation(TL.getLParenLoc());
 451   addSourceLocation(TL.getRParenLoc());
 452   Record.AddTypeSourceInfo(TL.getUnderlyingTInfo());
 453 }
 454
 455 void TypeLocWriter::VisitAutoTypeLoc(AutoTypeLoc TL) {
 456   addSourceLocation(TL.getNameLoc());
 457   Record.push_back(TL.isConstrained());
 458   if (TL.isConstrained()) {
 459     Record.AddNestedNameSpecifierLoc(TL.getNestedNameSpecifierLoc());
 460     addSourceLocation(TL.getTemplateKWLoc());
 461     addSourceLocation(TL.getConceptNameLoc());
 462     Record.AddDeclRef(TL.getFoundDecl());
 463     addSourceLocation(TL.getLAngleLoc());
 464     addSourceLocation(TL.getRAngleLoc());
 465     for (unsigned I = 0; I < TL.getNumArgs(); ++I)
 466       Record.AddTemplateArgumentLocInfo(TL.getTypePtr()->getArg(I).getKind(),
 467                                         TL.getArgLocInfo(I));
 468   }
 469   Record.push_back(TL.isDecltypeAuto());
 470   if (TL.isDecltypeAuto())
 471     addSourceLocation(TL.getRParenLoc());
 472 }
 473
 474 void TypeLocWriter::VisitDeducedTemplateSpecializationTypeLoc(
 475     DeducedTemplateSpecializationTypeLoc TL) {
 476   addSourceLocation(TL.getTemplateNameLoc());
 477 }
 478
 479 void TypeLocWriter::VisitRecordTypeLoc(RecordTypeLoc TL) {
 480   addSourceLocation(TL.getNameLoc());
 481 }
 482
 483 void TypeLocWriter::VisitEnumTypeLoc(EnumTypeLoc TL) {
 484   addSourceLocation(TL.getNameLoc());
 485 }
 486
 487 void TypeLocWriter::VisitAttributedTypeLoc(AttributedTypeLoc TL) {
 488   Record.AddAttr(TL.getAttr());
 489 }
 490
 491 void TypeLocWriter::VisitBTFTagAttributedTypeLoc(BTFTagAttributedTypeLoc TL) {
 492   // Nothing to do.
 493 }
 494
 495 void TypeLocWriter::VisitTemplateTypeParmTypeLoc(TemplateTypeParmTypeLoc TL) {
 496   addSourceLocation(TL.getNameLoc());
 497 }
 498
 499 void TypeLocWriter::VisitSubstTemplateTypeParmTypeLoc(
 500                                             SubstTemplateTypeParmTypeLoc TL) {
 501   addSourceLocation(TL.getNameLoc());
 502 }
 503
 504 void TypeLocWriter::VisitSubstTemplateTypeParmPackTypeLoc(
 505                                           SubstTemplateTypeParmPackTypeLoc TL) {
 506   addSourceLocation(TL.getNameLoc());
 507 }
 508
 509 void TypeLocWriter::VisitTemplateSpecializationTypeLoc(
 510                                            TemplateSpecializationTypeLoc TL) {
 511   addSourceLocation(TL.getTemplateKeywordLoc());
 512   addSourceLocation(TL.getTemplateNameLoc());
 513   addSourceLocation(TL.getLAngleLoc());
 514   addSourceLocation(TL.getRAngleLoc());
 515   for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
 516     Record.AddTemplateArgumentLocInfo(TL.getArgLoc(i).getArgument().getKind(),
 517                                       TL.getArgLoc(i).getLocInfo());
 518 }
 519
 520 void TypeLocWriter::VisitParenTypeLoc(ParenTypeLoc TL) {
 521   addSourceLocation(TL.getLParenLoc());
 522   addSourceLocation(TL.getRParenLoc());
 523 }
 524
 525 void TypeLocWriter::VisitMacroQualifiedTypeLoc(MacroQualifiedTypeLoc TL) {
 526   addSourceLocation(TL.getExpansionLoc());
 527 }
 528
 529 void TypeLocWriter::VisitElaboratedTypeLoc(ElaboratedTypeLoc TL) {
 530   addSourceLocation(TL.getElaboratedKeywordLoc());
 531   Record.AddNestedNameSpecifierLoc(TL.getQualifierLoc());
 532 }
 533
 534 void TypeLocWriter::VisitInjectedClassNameTypeLoc(InjectedClassNameTypeLoc TL) {
 535   addSourceLocation(TL.getNameLoc());
 536 }
 537
 538 void TypeLocWriter::VisitDependentNameTypeLoc(DependentNameTypeLoc TL) {
 539   addSourceLocation(TL.getElaboratedKeywordLoc());
 540   Record.AddNestedNameSpecifierLoc(TL.getQualifierLoc());
 541   addSourceLocation(TL.getNameLoc());
 542 }
 543
 544 void TypeLocWriter::VisitDependentTemplateSpecializationTypeLoc(
 545        DependentTemplateSpecializationTypeLoc TL) {
 546   addSourceLocation(TL.getElaboratedKeywordLoc());
 547   Record.AddNestedNameSpecifierLoc(TL.getQualifierLoc());
 548   addSourceLocation(TL.getTemplateKeywordLoc());
 549   addSourceLocation(TL.getTemplateNameLoc());
 550   addSourceLocation(TL.getLAngleLoc());
 551   addSourceLocation(TL.getRAngleLoc());
 552   for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I)
 553     Record.AddTemplateArgumentLocInfo(TL.getArgLoc(I).getArgument().getKind(),
 554                                       TL.getArgLoc(I).getLocInfo());
 555 }
 556
 557 void TypeLocWriter::VisitPackExpansionTypeLoc(PackExpansionTypeLoc TL) {
 558   addSourceLocation(TL.getEllipsisLoc());
 559 }
 560
 561 void TypeLocWriter::VisitObjCInterfaceTypeLoc(ObjCInterfaceTypeLoc TL) {
 562   addSourceLocation(TL.getNameLoc());
 563 }
 564
 565 void TypeLocWriter::VisitObjCObjectTypeLoc(ObjCObjectTypeLoc TL) {
 566   Record.push_back(TL.hasBaseTypeAsWritten());
 567   addSourceLocation(TL.getTypeArgsLAngleLoc());
 568   addSourceLocation(TL.getTypeArgsRAngleLoc());
 569   for (unsigned i = 0, e = TL.getNumTypeArgs(); i != e; ++i)
 570     Record.AddTypeSourceInfo(TL.getTypeArgTInfo(i));
 571   addSourceLocation(TL.getProtocolLAngleLoc());
 572   addSourceLocation(TL.getProtocolRAngleLoc());
 573   for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
 574     addSourceLocation(TL.getProtocolLoc(i));
 575 }
 576
 577 void TypeLocWriter::VisitObjCObjectPointerTypeLoc(ObjCObjectPointerTypeLoc TL) {
 578   addSourceLocation(TL.getStarLoc());
 579 }
 580
 581 void TypeLocWriter::VisitAtomicTypeLoc(AtomicTypeLoc TL) {
 582   addSourceLocation(TL.getKWLoc());
 583   addSourceLocation(TL.getLParenLoc());
 584   addSourceLocation(TL.getRParenLoc());
 585 }
 586
 587 void TypeLocWriter::VisitPipeTypeLoc(PipeTypeLoc TL) {
 588   addSourceLocation(TL.getKWLoc());
 589 }
 590
 591 void TypeLocWriter::VisitBitIntTypeLoc(clang::BitIntTypeLoc TL) {
 592   addSourceLocation(TL.getNameLoc());
 593 }
 594 void TypeLocWriter::VisitDependentBitIntTypeLoc(
 595     clang::DependentBitIntTypeLoc TL) {
 596   addSourceLocation(TL.getNameLoc());
 597 }
 598
 599 void ASTWriter::WriteTypeAbbrevs() {
 600   using namespace llvm;
 601
 602   std::shared_ptr<BitCodeAbbrev> Abv;
 603
 604   // Abbreviation for TYPE_EXT_QUAL
 605   Abv = std::make_shared<BitCodeAbbrev>();
 606   Abv->Add(BitCodeAbbrevOp(serialization::TYPE_EXT_QUAL));
 607   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Type
 608   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 3));   // Quals
 609   TypeExtQualAbbrev = Stream.EmitAbbrev(std::move(Abv));
 610 }
 611
 612 //===----------------------------------------------------------------------===//
 613 // ASTWriter Implementation
 614 //===----------------------------------------------------------------------===//
 615
 616 static void EmitBlockID(unsigned ID, const char *Name,
 617                         llvm::BitstreamWriter &Stream,
 618                         ASTWriter::RecordDataImpl &Record) {
 619   Record.clear();
 620   Record.push_back(ID);
 621   Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETBID, Record);
 622
 623   // Emit the block name if present.
 624   if (!Name || Name[0] == 0)
 625     return;
 626   Record.clear();
 627   while (*Name)
 628     Record.push_back(*Name++);
 629   Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_BLOCKNAME, Record);
 630 }
 631
 632 static void EmitRecordID(unsigned ID, const char *Name,
 633                          llvm::BitstreamWriter &Stream,
 634                          ASTWriter::RecordDataImpl &Record) {
 635   Record.clear();
 636   Record.push_back(ID);
 637   while (*Name)
 638     Record.push_back(*Name++);
 639   Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETRECORDNAME, Record);
 640 }
 641
 642 static void AddStmtsExprs(llvm::BitstreamWriter &Stream,
 643                           ASTWriter::RecordDataImpl &Record) {
 644 #define RECORD(X) EmitRecordID(X, #X, Stream, Record)
 645   RECORD(STMT_STOP);
 646   RECORD(STMT_NULL_PTR);
 647   RECORD(STMT_REF_PTR);
 648   RECORD(STMT_NULL);
 649   RECORD(STMT_COMPOUND);
 650   RECORD(STMT_CASE);
 651   RECORD(STMT_DEFAULT);
 652   RECORD(STMT_LABEL);
 653   RECORD(STMT_ATTRIBUTED);
 654   RECORD(STMT_IF);
 655   RECORD(STMT_SWITCH);
 656   RECORD(STMT_WHILE);
 657   RECORD(STMT_DO);
 658   RECORD(STMT_FOR);
 659   RECORD(STMT_GOTO);
 660   RECORD(STMT_INDIRECT_GOTO);
 661   RECORD(STMT_CONTINUE);
 662   RECORD(STMT_BREAK);
 663   RECORD(STMT_RETURN);
 664   RECORD(STMT_DECL);
 665   RECORD(STMT_GCCASM);
 666   RECORD(STMT_MSASM);
 667   RECORD(EXPR_PREDEFINED);
 668   RECORD(EXPR_DECL_REF);
 669   RECORD(EXPR_INTEGER_LITERAL);
 670   RECORD(EXPR_FIXEDPOINT_LITERAL);
 671   RECORD(EXPR_FLOATING_LITERAL);
 672   RECORD(EXPR_IMAGINARY_LITERAL);
 673   RECORD(EXPR_STRING_LITERAL);
 674   RECORD(EXPR_CHARACTER_LITERAL);
 675   RECORD(EXPR_PAREN);
 676   RECORD(EXPR_PAREN_LIST);
 677   RECORD(EXPR_UNARY_OPERATOR);
 678   RECORD(EXPR_SIZEOF_ALIGN_OF);
 679   RECORD(EXPR_ARRAY_SUBSCRIPT);
 680   RECORD(EXPR_CALL);
 681   RECORD(EXPR_MEMBER);
 682   RECORD(EXPR_BINARY_OPERATOR);
 683   RECORD(EXPR_COMPOUND_ASSIGN_OPERATOR);
 684   RECORD(EXPR_CONDITIONAL_OPERATOR);
 685   RECORD(EXPR_IMPLICIT_CAST);
 686   RECORD(EXPR_CSTYLE_CAST);
 687   RECORD(EXPR_COMPOUND_LITERAL);
 688   RECORD(EXPR_EXT_VECTOR_ELEMENT);
 689   RECORD(EXPR_INIT_LIST);
 690   RECORD(EXPR_DESIGNATED_INIT);
 691   RECORD(EXPR_DESIGNATED_INIT_UPDATE);
 692   RECORD(EXPR_IMPLICIT_VALUE_INIT);
 693   RECORD(EXPR_NO_INIT);
 694   RECORD(EXPR_VA_ARG);
 695   RECORD(EXPR_ADDR_LABEL);
 696   RECORD(EXPR_STMT);
 697   RECORD(EXPR_CHOOSE);
 698   RECORD(EXPR_GNU_NULL);
 699   RECORD(EXPR_SHUFFLE_VECTOR);
 700   RECORD(EXPR_BLOCK);
 701   RECORD(EXPR_GENERIC_SELECTION);
 702   RECORD(EXPR_OBJC_STRING_LITERAL);
 703   RECORD(EXPR_OBJC_BOXED_EXPRESSION);
 704   RECORD(EXPR_OBJC_ARRAY_LITERAL);
 705   RECORD(EXPR_OBJC_DICTIONARY_LITERAL);
 706   RECORD(EXPR_OBJC_ENCODE);
 707   RECORD(EXPR_OBJC_SELECTOR_EXPR);
 708   RECORD(EXPR_OBJC_PROTOCOL_EXPR);
 709   RECORD(EXPR_OBJC_IVAR_REF_EXPR);
 710   RECORD(EXPR_OBJC_PROPERTY_REF_EXPR);
 711   RECORD(EXPR_OBJC_KVC_REF_EXPR);
 712   RECORD(EXPR_OBJC_MESSAGE_EXPR);
 713   RECORD(STMT_OBJC_FOR_COLLECTION);
 714   RECORD(STMT_OBJC_CATCH);
 715   RECORD(STMT_OBJC_FINALLY);
 716   RECORD(STMT_OBJC_AT_TRY);
 717   RECORD(STMT_OBJC_AT_SYNCHRONIZED);
 718   RECORD(STMT_OBJC_AT_THROW);
 719   RECORD(EXPR_OBJC_BOOL_LITERAL);
 720   RECORD(STMT_CXX_CATCH);
 721   RECORD(STMT_CXX_TRY);
 722   RECORD(STMT_CXX_FOR_RANGE);
 723   RECORD(EXPR_CXX_OPERATOR_CALL);
 724   RECORD(EXPR_CXX_MEMBER_CALL);
 725   RECORD(EXPR_CXX_REWRITTEN_BINARY_OPERATOR);
 726   RECORD(EXPR_CXX_CONSTRUCT);
 727   RECORD(EXPR_CXX_TEMPORARY_OBJECT);
 728   RECORD(EXPR_CXX_STATIC_CAST);
 729   RECORD(EXPR_CXX_DYNAMIC_CAST);
 730   RECORD(EXPR_CXX_REINTERPRET_CAST);
 731   RECORD(EXPR_CXX_CONST_CAST);
 732   RECORD(EXPR_CXX_ADDRSPACE_CAST);
 733   RECORD(EXPR_CXX_FUNCTIONAL_CAST);
 734   RECORD(EXPR_USER_DEFINED_LITERAL);
 735   RECORD(EXPR_CXX_STD_INITIALIZER_LIST);
 736   RECORD(EXPR_CXX_BOOL_LITERAL);
 737   RECORD(EXPR_CXX_NULL_PTR_LITERAL);
 738   RECORD(EXPR_CXX_TYPEID_EXPR);
 739   RECORD(EXPR_CXX_TYPEID_TYPE);
 740   RECORD(EXPR_CXX_THIS);
 741   RECORD(EXPR_CXX_THROW);
 742   RECORD(EXPR_CXX_DEFAULT_ARG);
 743   RECORD(EXPR_CXX_DEFAULT_INIT);
 744   RECORD(EXPR_CXX_BIND_TEMPORARY);
 745   RECORD(EXPR_CXX_SCALAR_VALUE_INIT);
 746   RECORD(EXPR_CXX_NEW);
 747   RECORD(EXPR_CXX_DELETE);
 748   RECORD(EXPR_CXX_PSEUDO_DESTRUCTOR);
 749   RECORD(EXPR_EXPR_WITH_CLEANUPS);
 750   RECORD(EXPR_CXX_DEPENDENT_SCOPE_MEMBER);
 751   RECORD(EXPR_CXX_DEPENDENT_SCOPE_DECL_REF);
 752   RECORD(EXPR_CXX_UNRESOLVED_CONSTRUCT);
 753   RECORD(EXPR_CXX_UNRESOLVED_MEMBER);
 754   RECORD(EXPR_CXX_UNRESOLVED_LOOKUP);
 755   RECORD(EXPR_CXX_EXPRESSION_TRAIT);
 756   RECORD(EXPR_CXX_NOEXCEPT);
 757   RECORD(EXPR_OPAQUE_VALUE);
 758   RECORD(EXPR_BINARY_CONDITIONAL_OPERATOR);
 759   RECORD(EXPR_TYPE_TRAIT);
 760   RECORD(EXPR_ARRAY_TYPE_TRAIT);
 761   RECORD(EXPR_PACK_EXPANSION);
 762   RECORD(EXPR_SIZEOF_PACK);
 763   RECORD(EXPR_SUBST_NON_TYPE_TEMPLATE_PARM);
 764   RECORD(EXPR_SUBST_NON_TYPE_TEMPLATE_PARM_PACK);
 765   RECORD(EXPR_FUNCTION_PARM_PACK);
 766   RECORD(EXPR_MATERIALIZE_TEMPORARY);
 767   RECORD(EXPR_CUDA_KERNEL_CALL);
 768   RECORD(EXPR_CXX_UUIDOF_EXPR);
 769   RECORD(EXPR_CXX_UUIDOF_TYPE);
 770   RECORD(EXPR_LAMBDA);
 771 #undef RECORD
 772 }
 773
 774 void ASTWriter::WriteBlockInfoBlock() {
 775   RecordData Record;
 776   Stream.EnterBlockInfoBlock();
 777
 778 #define BLOCK(X) EmitBlockID(X ## _ID, #X, Stream, Record)
 779 #define RECORD(X) EmitRecordID(X, #X, Stream, Record)
 780
 781   // Control Block.
 782   BLOCK(CONTROL_BLOCK);
 783   RECORD(METADATA);
 784   RECORD(MODULE_NAME);
 785   RECORD(MODULE_DIRECTORY);
 786   RECORD(MODULE_MAP_FILE);
 787   RECORD(IMPORTS);
 788   RECORD(ORIGINAL_FILE);
 789   RECORD(ORIGINAL_FILE_ID);
 790   RECORD(INPUT_FILE_OFFSETS);
 791
 792   BLOCK(OPTIONS_BLOCK);
 793   RECORD(LANGUAGE_OPTIONS);
 794   RECORD(TARGET_OPTIONS);
 795   RECORD(FILE_SYSTEM_OPTIONS);
 796   RECORD(HEADER_SEARCH_OPTIONS);
 797   RECORD(PREPROCESSOR_OPTIONS);
 798
 799   BLOCK(INPUT_FILES_BLOCK);
 800   RECORD(INPUT_FILE);
 801   RECORD(INPUT_FILE_HASH);
 802
 803   // AST Top-Level Block.
 804   BLOCK(AST_BLOCK);
 805   RECORD(TYPE_OFFSET);
 806   RECORD(DECL_OFFSET);
 807   RECORD(IDENTIFIER_OFFSET);
 808   RECORD(IDENTIFIER_TABLE);
 809   RECORD(EAGERLY_DESERIALIZED_DECLS);
 810   RECORD(MODULAR_CODEGEN_DECLS);
 811   RECORD(SPECIAL_TYPES);
 812   RECORD(STATISTICS);
 813   RECORD(TENTATIVE_DEFINITIONS);
 814   RECORD(SELECTOR_OFFSETS);
 815   RECORD(METHOD_POOL);
 816   RECORD(PP_COUNTER_VALUE);
 817   RECORD(SOURCE_LOCATION_OFFSETS);
 818   RECORD(SOURCE_LOCATION_PRELOADS);
 819   RECORD(EXT_VECTOR_DECLS);
 820   RECORD(UNUSED_FILESCOPED_DECLS);
 821   RECORD(PPD_ENTITIES_OFFSETS);
 822   RECORD(VTABLE_USES);
 823   RECORD(PPD_SKIPPED_RANGES);
 824   RECORD(REFERENCED_SELECTOR_POOL);
 825   RECORD(TU_UPDATE_LEXICAL);
 826   RECORD(SEMA_DECL_REFS);
 827   RECORD(WEAK_UNDECLARED_IDENTIFIERS);
 828   RECORD(PENDING_IMPLICIT_INSTANTIATIONS);
 829   RECORD(UPDATE_VISIBLE);
 830   RECORD(DECL_UPDATE_OFFSETS);
 831   RECORD(DECL_UPDATES);
 832   RECORD(CUDA_SPECIAL_DECL_REFS);
 833   RECORD(HEADER_SEARCH_TABLE);
 834   RECORD(FP_PRAGMA_OPTIONS);
 835   RECORD(OPENCL_EXTENSIONS);
 836   RECORD(OPENCL_EXTENSION_TYPES);
 837   RECORD(OPENCL_EXTENSION_DECLS);
 838   RECORD(DELEGATING_CTORS);
 839   RECORD(KNOWN_NAMESPACES);
 840   RECORD(MODULE_OFFSET_MAP);
 841   RECORD(SOURCE_MANAGER_LINE_TABLE);
 842   RECORD(OBJC_CATEGORIES_MAP);
 843   RECORD(FILE_SORTED_DECLS);
 844   RECORD(IMPORTED_MODULES);
 845   RECORD(OBJC_CATEGORIES);
 846   RECORD(MACRO_OFFSET);
 847   RECORD(INTERESTING_IDENTIFIERS);
 848   RECORD(UNDEFINED_BUT_USED);
 849   RECORD(LATE_PARSED_TEMPLATE);
 850   RECORD(OPTIMIZE_PRAGMA_OPTIONS);
 851   RECORD(MSSTRUCT_PRAGMA_OPTIONS);
 852   RECORD(POINTERS_TO_MEMBERS_PRAGMA_OPTIONS);
 853   RECORD(UNUSED_LOCAL_TYPEDEF_NAME_CANDIDATES);
 854   RECORD(DELETE_EXPRS_TO_ANALYZE);
 855   RECORD(CUDA_PRAGMA_FORCE_HOST_DEVICE_DEPTH);
 856   RECORD(PP_CONDITIONAL_STACK);
 857   RECORD(DECLS_TO_CHECK_FOR_DEFERRED_DIAGS);
 858   RECORD(PP_INCLUDED_FILES);
 859   RECORD(PP_ASSUME_NONNULL_LOC);
 860
 861   // SourceManager Block.
 862   BLOCK(SOURCE_MANAGER_BLOCK);
 863   RECORD(SM_SLOC_FILE_ENTRY);
 864   RECORD(SM_SLOC_BUFFER_ENTRY);
 865   RECORD(SM_SLOC_BUFFER_BLOB);
 866   RECORD(SM_SLOC_BUFFER_BLOB_COMPRESSED);
 867   RECORD(SM_SLOC_EXPANSION_ENTRY);
 868
 869   // Preprocessor Block.
 870   BLOCK(PREPROCESSOR_BLOCK);
 871   RECORD(PP_MACRO_DIRECTIVE_HISTORY);
 872   RECORD(PP_MACRO_FUNCTION_LIKE);
 873   RECORD(PP_MACRO_OBJECT_LIKE);
 874   RECORD(PP_MODULE_MACRO);
 875   RECORD(PP_TOKEN);
 876
 877   // Submodule Block.
 878   BLOCK(SUBMODULE_BLOCK);
 879   RECORD(SUBMODULE_METADATA);
 880   RECORD(SUBMODULE_DEFINITION);
 881   RECORD(SUBMODULE_UMBRELLA_HEADER);
 882   RECORD(SUBMODULE_HEADER);
 883   RECORD(SUBMODULE_TOPHEADER);
 884   RECORD(SUBMODULE_UMBRELLA_DIR);
 885   RECORD(SUBMODULE_IMPORTS);
 886   RECORD(SUBMODULE_AFFECTING_MODULES);
 887   RECORD(SUBMODULE_EXPORTS);
 888   RECORD(SUBMODULE_REQUIRES);
 889   RECORD(SUBMODULE_EXCLUDED_HEADER);
 890   RECORD(SUBMODULE_LINK_LIBRARY);
 891   RECORD(SUBMODULE_CONFIG_MACRO);
 892   RECORD(SUBMODULE_CONFLICT);
 893   RECORD(SUBMODULE_PRIVATE_HEADER);
 894   RECORD(SUBMODULE_TEXTUAL_HEADER);
 895   RECORD(SUBMODULE_PRIVATE_TEXTUAL_HEADER);
 896   RECORD(SUBMODULE_INITIALIZERS);
 897   RECORD(SUBMODULE_EXPORT_AS);
 898
 899   // Comments Block.
 900   BLOCK(COMMENTS_BLOCK);
 901   RECORD(COMMENTS_RAW_COMMENT);
 902
 903   // Decls and Types block.
 904   BLOCK(DECLTYPES_BLOCK);
 905   RECORD(TYPE_EXT_QUAL);
 906   RECORD(TYPE_COMPLEX);
 907   RECORD(TYPE_POINTER);
 908   RECORD(TYPE_BLOCK_POINTER);
 909   RECORD(TYPE_LVALUE_REFERENCE);
 910   RECORD(TYPE_RVALUE_REFERENCE);
 911   RECORD(TYPE_MEMBER_POINTER);
 912   RECORD(TYPE_CONSTANT_ARRAY);
 913   RECORD(TYPE_INCOMPLETE_ARRAY);
 914   RECORD(TYPE_VARIABLE_ARRAY);
 915   RECORD(TYPE_VECTOR);
 916   RECORD(TYPE_EXT_VECTOR);
 917   RECORD(TYPE_FUNCTION_NO_PROTO);
 918   RECORD(TYPE_FUNCTION_PROTO);
 919   RECORD(TYPE_TYPEDEF);
 920   RECORD(TYPE_TYPEOF_EXPR);
 921   RECORD(TYPE_TYPEOF);
 922   RECORD(TYPE_RECORD);
 923   RECORD(TYPE_ENUM);
 924   RECORD(TYPE_OBJC_INTERFACE);
 925   RECORD(TYPE_OBJC_OBJECT_POINTER);
 926   RECORD(TYPE_DECLTYPE);
 927   RECORD(TYPE_ELABORATED);
 928   RECORD(TYPE_SUBST_TEMPLATE_TYPE_PARM);
 929   RECORD(TYPE_UNRESOLVED_USING);
 930   RECORD(TYPE_INJECTED_CLASS_NAME);
 931   RECORD(TYPE_OBJC_OBJECT);
 932   RECORD(TYPE_TEMPLATE_TYPE_PARM);
 933   RECORD(TYPE_TEMPLATE_SPECIALIZATION);
 934   RECORD(TYPE_DEPENDENT_NAME);
 935   RECORD(TYPE_DEPENDENT_TEMPLATE_SPECIALIZATION);
 936   RECORD(TYPE_DEPENDENT_SIZED_ARRAY);
 937   RECORD(TYPE_PAREN);
 938   RECORD(TYPE_MACRO_QUALIFIED);
 939   RECORD(TYPE_PACK_EXPANSION);
 940   RECORD(TYPE_ATTRIBUTED);
 941   RECORD(TYPE_SUBST_TEMPLATE_TYPE_PARM_PACK);
 942   RECORD(TYPE_AUTO);
 943   RECORD(TYPE_UNARY_TRANSFORM);
 944   RECORD(TYPE_ATOMIC);
 945   RECORD(TYPE_DECAYED);
 946   RECORD(TYPE_ADJUSTED);
 947   RECORD(TYPE_OBJC_TYPE_PARAM);
 948   RECORD(LOCAL_REDECLARATIONS);
 949   RECORD(DECL_TYPEDEF);
 950   RECORD(DECL_TYPEALIAS);
 951   RECORD(DECL_ENUM);
 952   RECORD(DECL_RECORD);
 953   RECORD(DECL_ENUM_CONSTANT);
 954   RECORD(DECL_FUNCTION);
 955   RECORD(DECL_OBJC_METHOD);
 956   RECORD(DECL_OBJC_INTERFACE);
 957   RECORD(DECL_OBJC_PROTOCOL);
 958   RECORD(DECL_OBJC_IVAR);
 959   RECORD(DECL_OBJC_AT_DEFS_FIELD);
 960   RECORD(DECL_OBJC_CATEGORY);
 961   RECORD(DECL_OBJC_CATEGORY_IMPL);
 962   RECORD(DECL_OBJC_IMPLEMENTATION);
 963   RECORD(DECL_OBJC_COMPATIBLE_ALIAS);
 964   RECORD(DECL_OBJC_PROPERTY);
 965   RECORD(DECL_OBJC_PROPERTY_IMPL);
 966   RECORD(DECL_FIELD);
 967   RECORD(DECL_MS_PROPERTY);
 968   RECORD(DECL_VAR);
 969   RECORD(DECL_IMPLICIT_PARAM);
 970   RECORD(DECL_PARM_VAR);
 971   RECORD(DECL_FILE_SCOPE_ASM);
 972   RECORD(DECL_BLOCK);
 973   RECORD(DECL_CONTEXT_LEXICAL);
 974   RECORD(DECL_CONTEXT_VISIBLE);
 975   RECORD(DECL_NAMESPACE);
 976   RECORD(DECL_NAMESPACE_ALIAS);
 977   RECORD(DECL_USING);
 978   RECORD(DECL_USING_SHADOW);
 979   RECORD(DECL_USING_DIRECTIVE);
 980   RECORD(DECL_UNRESOLVED_USING_VALUE);
 981   RECORD(DECL_UNRESOLVED_USING_TYPENAME);
 982   RECORD(DECL_LINKAGE_SPEC);
 983   RECORD(DECL_CXX_RECORD);
 984   RECORD(DECL_CXX_METHOD);
 985   RECORD(DECL_CXX_CONSTRUCTOR);
 986   RECORD(DECL_CXX_DESTRUCTOR);
 987   RECORD(DECL_CXX_CONVERSION);
 988   RECORD(DECL_ACCESS_SPEC);
 989   RECORD(DECL_FRIEND);
 990   RECORD(DECL_FRIEND_TEMPLATE);
 991   RECORD(DECL_CLASS_TEMPLATE);
 992   RECORD(DECL_CLASS_TEMPLATE_SPECIALIZATION);
 993   RECORD(DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION);
 994   RECORD(DECL_VAR_TEMPLATE);
 995   RECORD(DECL_VAR_TEMPLATE_SPECIALIZATION);
 996   RECORD(DECL_VAR_TEMPLATE_PARTIAL_SPECIALIZATION);
 997   RECORD(DECL_FUNCTION_TEMPLATE);
 998   RECORD(DECL_TEMPLATE_TYPE_PARM);
 999   RECORD(DECL_NON_TYPE_TEMPLATE_PARM);
1000   RECORD(DECL_TEMPLATE_TEMPLATE_PARM);
1001   RECORD(DECL_CONCEPT);
1002   RECORD(DECL_REQUIRES_EXPR_BODY);
1003   RECORD(DECL_TYPE_ALIAS_TEMPLATE);
1004   RECORD(DECL_STATIC_ASSERT);
1005   RECORD(DECL_CXX_BASE_SPECIFIERS);
1006   RECORD(DECL_CXX_CTOR_INITIALIZERS);
1007   RECORD(DECL_INDIRECTFIELD);
1008   RECORD(DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK);
1009   RECORD(DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK);
1010   RECORD(DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION);
1011   RECORD(DECL_IMPORT);
1012   RECORD(DECL_OMP_THREADPRIVATE);
1013   RECORD(DECL_EMPTY);
1014   RECORD(DECL_OBJC_TYPE_PARAM);
1015   RECORD(DECL_OMP_CAPTUREDEXPR);
1016   RECORD(DECL_PRAGMA_COMMENT);
1017   RECORD(DECL_PRAGMA_DETECT_MISMATCH);
1018   RECORD(DECL_OMP_DECLARE_REDUCTION);
1019   RECORD(DECL_OMP_ALLOCATE);
1020
1021   // Statements and Exprs can occur in the Decls and Types block.
1022   AddStmtsExprs(Stream, Record);
1023
1024   BLOCK(PREPROCESSOR_DETAIL_BLOCK);
1025   RECORD(PPD_MACRO_EXPANSION);
1026   RECORD(PPD_MACRO_DEFINITION);
1027   RECORD(PPD_INCLUSION_DIRECTIVE);
1028
1029   // Decls and Types block.
1030   BLOCK(EXTENSION_BLOCK);
1031   RECORD(EXTENSION_METADATA);
1032
1033   BLOCK(UNHASHED_CONTROL_BLOCK);
1034   RECORD(SIGNATURE);
1035   RECORD(AST_BLOCK_HASH);
1036   RECORD(DIAGNOSTIC_OPTIONS);
1037   RECORD(DIAG_PRAGMA_MAPPINGS);
1038
1039 #undef RECORD
1040 #undef BLOCK
1041   Stream.ExitBlock();
1042 }
1043
1044 /// Prepares a path for being written to an AST file by converting it
1045 /// to an absolute path and removing nested './'s.
1046 ///
1047 /// \return \c true if the path was changed.
1048 static bool cleanPathForOutput(FileManager &FileMgr,
1049                                SmallVectorImpl<char> &Path) {
1050   bool Changed = FileMgr.makeAbsolutePath(Path);
1051   return Changed | llvm::sys::path::remove_dots(Path);
1052 }
1053
1054 /// Adjusts the given filename to only write out the portion of the
1055 /// filename that is not part of the system root directory.
1056 ///
1057 /// \param Filename the file name to adjust.
1058 ///
1059 /// \param BaseDir When non-NULL, the PCH file is a relocatable AST file and
1060 /// the returned filename will be adjusted by this root directory.
1061 ///
1062 /// \returns either the original filename (if it needs no adjustment) or the
1063 /// adjusted filename (which points into the @p Filename parameter).
1064 static const char *
1065 adjustFilenameForRelocatableAST(const char *Filename, StringRef BaseDir) {
1066   assert(Filename && "No file name to adjust?");
1067
1068   if (BaseDir.empty())
1069     return Filename;
1070
1071   // Verify that the filename and the system root have the same prefix.
1072   unsigned Pos = 0;
1073   for (; Filename[Pos] && Pos < BaseDir.size(); ++Pos)
1074     if (Filename[Pos] != BaseDir[Pos])
1075       return Filename; // Prefixes don't match.
1076
1077   // We hit the end of the filename before we hit the end of the system root.
1078   if (!Filename[Pos])
1079     return Filename;
1080
1081   // If there's not a path separator at the end of the base directory nor
1082   // immediately after it, then this isn't within the base directory.
1083   if (!llvm::sys::path::is_separator(Filename[Pos])) {
1084     if (!llvm::sys::path::is_separator(BaseDir.back()))
1085       return Filename;
1086   } else {
1087     // If the file name has a '/' at the current position, skip over the '/'.
1088     // We distinguish relative paths from absolute paths by the
1089     // absence of '/' at the beginning of relative paths.
1090     //
1091     // FIXME: This is wrong. We distinguish them by asking if the path is
1092     // absolute, which isn't the same thing. And there might be multiple '/'s
1093     // in a row. Use a better mechanism to indicate whether we have emitted an
1094     // absolute or relative path.
1095     ++Pos;
1096   }
1097
1098   return Filename + Pos;
1099 }
1100
1101 std::pair<ASTFileSignature, ASTFileSignature>
1102 ASTWriter::createSignature(StringRef AllBytes, StringRef ASTBlockBytes) {
1103   llvm::SHA1 Hasher;
1104   Hasher.update(ASTBlockBytes);
1105   ASTFileSignature ASTBlockHash = ASTFileSignature::create(Hasher.result());
1106
1107   // Add the remaining bytes (i.e. bytes before the unhashed control block that
1108   // are not part of the AST block).
1109   Hasher.update(
1110       AllBytes.take_front(ASTBlockBytes.bytes_end() - AllBytes.bytes_begin()));
1111   Hasher.update(
1112       AllBytes.take_back(AllBytes.bytes_end() - ASTBlockBytes.bytes_end()));
1113   ASTFileSignature Signature = ASTFileSignature::create(Hasher.result());
1114
1115   return std::make_pair(ASTBlockHash, Signature);
1116 }
1117
1118 ASTFileSignature ASTWriter::writeUnhashedControlBlock(Preprocessor &PP,
1119                                                       ASTContext &Context) {
1120   using namespace llvm;
1121
1122   // Flush first to prepare the PCM hash (signature).
1123   Stream.FlushToWord();
1124   auto StartOfUnhashedControl = Stream.GetCurrentBitNo() >> 3;
1125
1126   // Enter the block and prepare to write records.
1127   RecordData Record;
1128   Stream.EnterSubblock(UNHASHED_CONTROL_BLOCK_ID, 5);
1129
1130   // For implicit modules, write the hash of the PCM as its signature.
1131   ASTFileSignature Signature;
1132   if (WritingModule &&
1133       PP.getHeaderSearchInfo().getHeaderSearchOpts().ModulesHashContent) {
1134     ASTFileSignature ASTBlockHash;
1135     auto ASTBlockStartByte = ASTBlockRange.first >> 3;
1136     auto ASTBlockByteLength = (ASTBlockRange.second >> 3) - ASTBlockStartByte;
1137     std::tie(ASTBlockHash, Signature) = createSignature(
1138         StringRef(Buffer.begin(), StartOfUnhashedControl),
1139         StringRef(Buffer.begin() + ASTBlockStartByte, ASTBlockByteLength));
1140
1141     Record.append(ASTBlockHash.begin(), ASTBlockHash.end());
1142     Stream.EmitRecord(AST_BLOCK_HASH, Record);
1143     Record.clear();
1144     Record.append(Signature.begin(), Signature.end());
1145     Stream.EmitRecord(SIGNATURE, Record);
1146     Record.clear();
1147   }
1148
1149   // Diagnostic options.
1150   const auto &Diags = Context.getDiagnostics();
1151   const DiagnosticOptions &DiagOpts = Diags.getDiagnosticOptions();
1152 #define DIAGOPT(Name, Bits, Default) Record.push_back(DiagOpts.Name);
1153 #define ENUM_DIAGOPT(Name, Type, Bits, Default)                                \
1154   Record.push_back(static_cast<unsigned>(DiagOpts.get##Name()));
1155 #include "clang/Basic/DiagnosticOptions.def"
1156   Record.push_back(DiagOpts.Warnings.size());
1157   for (unsigned I = 0, N = DiagOpts.Warnings.size(); I != N; ++I)
1158     AddString(DiagOpts.Warnings[I], Record);
1159   Record.push_back(DiagOpts.Remarks.size());
1160   for (unsigned I = 0, N = DiagOpts.Remarks.size(); I != N; ++I)
1161     AddString(DiagOpts.Remarks[I], Record);
1162   // Note: we don't serialize the log or serialization file names, because they
1163   // are generally transient files and will almost always be overridden.
1164   Stream.EmitRecord(DIAGNOSTIC_OPTIONS, Record);
1165   Record.clear();
1166
1167   // Write out the diagnostic/pragma mappings.
1168   WritePragmaDiagnosticMappings(Diags, /* isModule = */ WritingModule);
1169
1170   // Header search entry usage.
1171   auto HSEntryUsage = PP.getHeaderSearchInfo().computeUserEntryUsage();
1172   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1173   Abbrev->Add(BitCodeAbbrevOp(HEADER_SEARCH_ENTRY_USAGE));
1174   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // Number of bits.
1175   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));      // Bit vector.
1176   unsigned HSUsageAbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
1177   {
1178     RecordData::value_type Record[] = {HEADER_SEARCH_ENTRY_USAGE,
1179                                        HSEntryUsage.size()};
1180     Stream.EmitRecordWithBlob(HSUsageAbbrevCode, Record, bytes(HSEntryUsage));
1181   }
1182
1183   // Leave the options block.
1184   Stream.ExitBlock();
1185   return Signature;
1186 }
1187
1188 /// Write the control block.
1189 void ASTWriter::WriteControlBlock(Preprocessor &PP, ASTContext &Context,
1190                                   StringRef isysroot) {
1191   using namespace llvm;
1192
1193   Stream.EnterSubblock(CONTROL_BLOCK_ID, 5);
1194   RecordData Record;
1195
1196   // Metadata
1197   auto MetadataAbbrev = std::make_shared<BitCodeAbbrev>();
1198   MetadataAbbrev->Add(BitCodeAbbrevOp(METADATA));
1199   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Major
1200   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Minor
1201   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Clang maj.
1202   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Clang min.
1203   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Relocatable
1204   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Timestamps
1205   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Errors
1206   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // SVN branch/tag
1207   unsigned MetadataAbbrevCode = Stream.EmitAbbrev(std::move(MetadataAbbrev));
1208   assert((!WritingModule || isysroot.empty()) &&
1209          "writing module as a relocatable PCH?");
1210   {
1211     RecordData::value_type Record[] = {
1212         METADATA,
1213         VERSION_MAJOR,
1214         VERSION_MINOR,
1215         CLANG_VERSION_MAJOR,
1216         CLANG_VERSION_MINOR,
1217         !isysroot.empty(),
1218         IncludeTimestamps,
1219         ASTHasCompilerErrors};
1220     Stream.EmitRecordWithBlob(MetadataAbbrevCode, Record,
1221                               getClangFullRepositoryVersion());
1222   }
1223
1224   if (WritingModule) {
1225     // Module name
1226     auto Abbrev = std::make_shared<BitCodeAbbrev>();
1227     Abbrev->Add(BitCodeAbbrevOp(MODULE_NAME));
1228     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
1229     unsigned AbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
1230     RecordData::value_type Record[] = {MODULE_NAME};
1231     Stream.EmitRecordWithBlob(AbbrevCode, Record, WritingModule->Name);
1232   }
1233
1234   if (WritingModule && WritingModule->Directory) {
1235     SmallString<128> BaseDir;
1236     if (PP.getHeaderSearchInfo().getHeaderSearchOpts().ModuleFileHomeIsCwd) {
1237       // Use the current working directory as the base path for all inputs.
1238       auto *CWD =
1239           Context.getSourceManager().getFileManager().getDirectory(".").get();
1240       BaseDir.assign(CWD->getName());
1241     } else {
1242       BaseDir.assign(WritingModule->Directory->getName());
1243     }
1244     cleanPathForOutput(Context.getSourceManager().getFileManager(), BaseDir);
1245
1246     // If the home of the module is the current working directory, then we
1247     // want to pick up the cwd of the build process loading the module, not
1248     // our cwd, when we load this module.
1249     if (!(PP.getHeaderSearchInfo()
1250               .getHeaderSearchOpts()
1251               .ModuleMapFileHomeIsCwd ||
1252           PP.getHeaderSearchInfo().getHeaderSearchOpts().ModuleFileHomeIsCwd) ||
1253         WritingModule->Directory->getName() != StringRef(".")) {
1254       // Module directory.
1255       auto Abbrev = std::make_shared<BitCodeAbbrev>();
1256       Abbrev->Add(BitCodeAbbrevOp(MODULE_DIRECTORY));
1257       Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Directory
1258       unsigned AbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
1259
1260       RecordData::value_type Record[] = {MODULE_DIRECTORY};
1261       Stream.EmitRecordWithBlob(AbbrevCode, Record, BaseDir);
1262     }
1263
1264     // Write out all other paths relative to the base directory if possible.
1265     BaseDirectory.assign(BaseDir.begin(), BaseDir.end());
1266   } else if (!isysroot.empty()) {
1267     // Write out paths relative to the sysroot if possible.
1268     BaseDirectory = std::string(isysroot);
1269   }
1270
1271   // Module map file
1272   if (WritingModule && WritingModule->Kind == Module::ModuleMapModule) {
1273     Record.clear();
1274
1275     auto &Map = PP.getHeaderSearchInfo().getModuleMap();
1276     AddPath(WritingModule->PresumedModuleMapFile.empty()
1277                 ? Map.getModuleMapFileForUniquing(WritingModule)->getName()
1278                 : StringRef(WritingModule->PresumedModuleMapFile),
1279             Record);
1280
1281     // Additional module map files.
1282     if (auto *AdditionalModMaps =
1283             Map.getAdditionalModuleMapFiles(WritingModule)) {
1284       Record.push_back(AdditionalModMaps->size());
1285       SmallVector<const FileEntry *, 1> ModMaps(AdditionalModMaps->begin(),
1286                                                 AdditionalModMaps->end());
1287       llvm::sort(ModMaps, [](const FileEntry *A, const FileEntry *B) {
1288         return A->getName() < B->getName();
1289       });
1290       for (const FileEntry *F : ModMaps)
1291         AddPath(F->getName(), Record);
1292     } else {
1293       Record.push_back(0);
1294     }
1295
1296     Stream.EmitRecord(MODULE_MAP_FILE, Record);
1297   }
1298
1299   // Imports
1300   if (Chain) {
1301     serialization::ModuleManager &Mgr = Chain->getModuleManager();
1302     Record.clear();
1303
1304     for (ModuleFile &M : Mgr) {
1305       // Skip modules that weren't directly imported.
1306       if (!M.isDirectlyImported())
1307         continue;
1308
1309       Record.push_back((unsigned)M.Kind); // FIXME: Stable encoding
1310       AddSourceLocation(M.ImportLoc, Record);
1311
1312       // If we have calculated signature, there is no need to store
1313       // the size or timestamp.
1314       Record.push_back(M.Signature ? 0 : M.File->getSize());
1315       Record.push_back(M.Signature ? 0 : getTimestampForOutput(M.File));
1316
1317       llvm::append_range(Record, M.Signature);
1318
1319       AddString(M.ModuleName, Record);
1320       AddPath(M.FileName, Record);
1321     }
1322     Stream.EmitRecord(IMPORTS, Record);
1323   }
1324
1325   // Write the options block.
1326   Stream.EnterSubblock(OPTIONS_BLOCK_ID, 4);
1327
1328   // Language options.
1329   Record.clear();
1330   const LangOptions &LangOpts = Context.getLangOpts();
1331 #define LANGOPT(Name, Bits, Default, Description) \
1332   Record.push_back(LangOpts.Name);
1333 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
1334   Record.push_back(static_cast<unsigned>(LangOpts.get##Name()));
1335 #include "clang/Basic/LangOptions.def"
1336 #define SANITIZER(NAME, ID)                                                    \
1337   Record.push_back(LangOpts.Sanitize.has(SanitizerKind::ID));
1338 #include "clang/Basic/Sanitizers.def"
1339
1340   Record.push_back(LangOpts.ModuleFeatures.size());
1341   for (StringRef Feature : LangOpts.ModuleFeatures)
1342     AddString(Feature, Record);
1343
1344   Record.push_back((unsigned) LangOpts.ObjCRuntime.getKind());
1345   AddVersionTuple(LangOpts.ObjCRuntime.getVersion(), Record);
1346
1347   AddString(LangOpts.CurrentModule, Record);
1348
1349   // Comment options.
1350   Record.push_back(LangOpts.CommentOpts.BlockCommandNames.size());
1351   for (const auto &I : LangOpts.CommentOpts.BlockCommandNames) {
1352     AddString(I, Record);
1353   }
1354   Record.push_back(LangOpts.CommentOpts.ParseAllComments);
1355
1356   // OpenMP offloading options.
1357   Record.push_back(LangOpts.OMPTargetTriples.size());
1358   for (auto &T : LangOpts.OMPTargetTriples)
1359     AddString(T.getTriple(), Record);
1360
1361   AddString(LangOpts.OMPHostIRFile, Record);
1362
1363   Stream.EmitRecord(LANGUAGE_OPTIONS, Record);
1364
1365   // Target options.
1366   Record.clear();
1367   const TargetInfo &Target = Context.getTargetInfo();
1368   const TargetOptions &TargetOpts = Target.getTargetOpts();
1369   AddString(TargetOpts.Triple, Record);
1370   AddString(TargetOpts.CPU, Record);
1371   AddString(TargetOpts.TuneCPU, Record);
1372   AddString(TargetOpts.ABI, Record);
1373   Record.push_back(TargetOpts.FeaturesAsWritten.size());
1374   for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size(); I != N; ++I) {
1375     AddString(TargetOpts.FeaturesAsWritten[I], Record);
1376   }
1377   Record.push_back(TargetOpts.Features.size());
1378   for (unsigned I = 0, N = TargetOpts.Features.size(); I != N; ++I) {
1379     AddString(TargetOpts.Features[I], Record);
1380   }
1381   Stream.EmitRecord(TARGET_OPTIONS, Record);
1382
1383   // File system options.
1384   Record.clear();
1385   const FileSystemOptions &FSOpts =
1386       Context.getSourceManager().getFileManager().getFileSystemOpts();
1387   AddString(FSOpts.WorkingDir, Record);
1388   Stream.EmitRecord(FILE_SYSTEM_OPTIONS, Record);
1389
1390   // Header search options.
1391   Record.clear();
1392   const HeaderSearchOptions &HSOpts
1393     = PP.getHeaderSearchInfo().getHeaderSearchOpts();
1394   AddString(HSOpts.Sysroot, Record);
1395
1396   // Include entries.
1397   Record.push_back(HSOpts.UserEntries.size());
1398   for (unsigned I = 0, N = HSOpts.UserEntries.size(); I != N; ++I) {
1399     const HeaderSearchOptions::Entry &Entry = HSOpts.UserEntries[I];
1400     AddString(Entry.Path, Record);
1401     Record.push_back(static_cast<unsigned>(Entry.Group));
1402     Record.push_back(Entry.IsFramework);
1403     Record.push_back(Entry.IgnoreSysRoot);
1404   }
1405
1406   // System header prefixes.
1407   Record.push_back(HSOpts.SystemHeaderPrefixes.size());
1408   for (unsigned I = 0, N = HSOpts.SystemHeaderPrefixes.size(); I != N; ++I) {
1409     AddString(HSOpts.SystemHeaderPrefixes[I].Prefix, Record);
1410     Record.push_back(HSOpts.SystemHeaderPrefixes[I].IsSystemHeader);
1411   }
1412
1413   AddString(HSOpts.ResourceDir, Record);
1414   AddString(HSOpts.ModuleCachePath, Record);
1415   AddString(HSOpts.ModuleUserBuildPath, Record);
1416   Record.push_back(HSOpts.DisableModuleHash);
1417   Record.push_back(HSOpts.ImplicitModuleMaps);
1418   Record.push_back(HSOpts.ModuleMapFileHomeIsCwd);
1419   Record.push_back(HSOpts.EnablePrebuiltImplicitModules);
1420   Record.push_back(HSOpts.UseBuiltinIncludes);
1421   Record.push_back(HSOpts.UseStandardSystemIncludes);
1422   Record.push_back(HSOpts.UseStandardCXXIncludes);
1423   Record.push_back(HSOpts.UseLibcxx);
1424   // Write out the specific module cache path that contains the module files.
1425   AddString(PP.getHeaderSearchInfo().getModuleCachePath(), Record);
1426   Stream.EmitRecord(HEADER_SEARCH_OPTIONS, Record);
1427
1428   // Preprocessor options.
1429   Record.clear();
1430   const PreprocessorOptions &PPOpts = PP.getPreprocessorOpts();
1431
1432   // Macro definitions.
1433   Record.push_back(PPOpts.Macros.size());
1434   for (unsigned I = 0, N = PPOpts.Macros.size(); I != N; ++I) {
1435     AddString(PPOpts.Macros[I].first, Record);
1436     Record.push_back(PPOpts.Macros[I].second);
1437   }
1438
1439   // Includes
1440   Record.push_back(PPOpts.Includes.size());
1441   for (unsigned I = 0, N = PPOpts.Includes.size(); I != N; ++I)
1442     AddString(PPOpts.Includes[I], Record);
1443
1444   // Macro includes
1445   Record.push_back(PPOpts.MacroIncludes.size());
1446   for (unsigned I = 0, N = PPOpts.MacroIncludes.size(); I != N; ++I)
1447     AddString(PPOpts.MacroIncludes[I], Record);
1448
1449   Record.push_back(PPOpts.UsePredefines);
1450   // Detailed record is important since it is used for the module cache hash.
1451   Record.push_back(PPOpts.DetailedRecord);
1452   AddString(PPOpts.ImplicitPCHInclude, Record);
1453   Record.push_back(static_cast<unsigned>(PPOpts.ObjCXXARCStandardLibrary));
1454   Stream.EmitRecord(PREPROCESSOR_OPTIONS, Record);
1455
1456   // Leave the options block.
1457   Stream.ExitBlock();
1458
1459   // Original file name and file ID
1460   SourceManager &SM = Context.getSourceManager();
1461   if (const FileEntry *MainFile = SM.getFileEntryForID(SM.getMainFileID())) {
1462     auto FileAbbrev = std::make_shared<BitCodeAbbrev>();
1463     FileAbbrev->Add(BitCodeAbbrevOp(ORIGINAL_FILE));
1464     FileAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // File ID
1465     FileAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // File name
1466     unsigned FileAbbrevCode = Stream.EmitAbbrev(std::move(FileAbbrev));
1467
1468     Record.clear();
1469     Record.push_back(ORIGINAL_FILE);
1470     Record.push_back(SM.getMainFileID().getOpaqueValue());
1471     EmitRecordWithPath(FileAbbrevCode, Record, MainFile->getName());
1472   }
1473
1474   Record.clear();
1475   Record.push_back(SM.getMainFileID().getOpaqueValue());
1476   Stream.EmitRecord(ORIGINAL_FILE_ID, Record);
1477
1478   std::set<const FileEntry *> AffectingModuleMaps;
1479   if (WritingModule) {
1480     AffectingModuleMaps =
1481         GetAllModuleMaps(PP.getHeaderSearchInfo(), WritingModule);
1482   }
1483
1484   WriteInputFiles(Context.SourceMgr,
1485                   PP.getHeaderSearchInfo().getHeaderSearchOpts(),
1486                   AffectingModuleMaps);
1487   Stream.ExitBlock();
1488 }
1489
1490 namespace  {
1491
1492 /// An input file.
1493 struct InputFileEntry {
1494   const FileEntry *File;
1495   bool IsSystemFile;
1496   bool IsTransient;
1497   bool BufferOverridden;
1498   bool IsTopLevelModuleMap;
1499   uint32_t ContentHash[2];
1500 };
1501
1502 } // namespace
1503
1504 void ASTWriter::WriteInputFiles(
1505     SourceManager &SourceMgr, HeaderSearchOptions &HSOpts,
1506     std::set<const FileEntry *> &AffectingModuleMaps) {
1507   using namespace llvm;
1508
1509   Stream.EnterSubblock(INPUT_FILES_BLOCK_ID, 4);
1510
1511   // Create input-file abbreviation.
1512   auto IFAbbrev = std::make_shared<BitCodeAbbrev>();
1513   IFAbbrev->Add(BitCodeAbbrevOp(INPUT_FILE));
1514   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ID
1515   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 12)); // Size
1516   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 32)); // Modification time
1517   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Overridden
1518   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Transient
1519   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Module map
1520   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // File name
1521   unsigned IFAbbrevCode = Stream.EmitAbbrev(std::move(IFAbbrev));
1522
1523   // Create input file hash abbreviation.
1524   auto IFHAbbrev = std::make_shared<BitCodeAbbrev>();
1525   IFHAbbrev->Add(BitCodeAbbrevOp(INPUT_FILE_HASH));
1526   IFHAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1527   IFHAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1528   unsigned IFHAbbrevCode = Stream.EmitAbbrev(std::move(IFHAbbrev));
1529
1530   // Get all ContentCache objects for files, sorted by whether the file is a
1531   // system one or not. System files go at the back, users files at the front.
1532   std::deque<InputFileEntry> SortedFiles;
1533   for (unsigned I = 1, N = SourceMgr.local_sloc_entry_size(); I != N; ++I) {
1534     // Get this source location entry.
1535     const SrcMgr::SLocEntry *SLoc = &SourceMgr.getLocalSLocEntry(I);
1536     assert(&SourceMgr.getSLocEntry(FileID::get(I)) == SLoc);
1537
1538     // We only care about file entries that were not overridden.
1539     if (!SLoc->isFile())
1540       continue;
1541     const SrcMgr::FileInfo &File = SLoc->getFile();
1542     const SrcMgr::ContentCache *Cache = &File.getContentCache();
1543     if (!Cache->OrigEntry)
1544       continue;
1545
1546     if (isModuleMap(File.getFileCharacteristic()) &&
1547         !isSystem(File.getFileCharacteristic()) &&
1548         !AffectingModuleMaps.empty() &&
1549         AffectingModuleMaps.find(Cache->OrigEntry) ==
1550             AffectingModuleMaps.end()) {
1551       SkippedModuleMaps.insert(Cache->OrigEntry);
1552       // Do not emit modulemaps that do not affect current module.
1553       continue;
1554     }
1555
1556     InputFileEntry Entry;
1557     Entry.File = Cache->OrigEntry;
1558     Entry.IsSystemFile = isSystem(File.getFileCharacteristic());
1559     Entry.IsTransient = Cache->IsTransient;
1560     Entry.BufferOverridden = Cache->BufferOverridden;
1561     Entry.IsTopLevelModuleMap = isModuleMap(File.getFileCharacteristic()) &&
1562                                 File.getIncludeLoc().isInvalid();
1563
1564     auto ContentHash = hash_code(-1);
1565     if (PP->getHeaderSearchInfo()
1566             .getHeaderSearchOpts()
1567             .ValidateASTInputFilesContent) {
1568       auto MemBuff = Cache->getBufferIfLoaded();
1569       if (MemBuff)
1570         ContentHash = hash_value(MemBuff->getBuffer());
1571       else
1572         // FIXME: The path should be taken from the FileEntryRef.
1573         PP->Diag(SourceLocation(), diag::err_module_unable_to_hash_content)
1574             << Entry.File->getName();
1575     }
1576     auto CH = llvm::APInt(64, ContentHash);
1577     Entry.ContentHash[0] =
1578         static_cast<uint32_t>(CH.getLoBits(32).getZExtValue());
1579     Entry.ContentHash[1] =
1580         static_cast<uint32_t>(CH.getHiBits(32).getZExtValue());
1581
1582     if (Entry.IsSystemFile)
1583       SortedFiles.push_back(Entry);
1584     else
1585       SortedFiles.push_front(Entry);
1586   }
1587
1588   unsigned UserFilesNum = 0;
1589   // Write out all of the input files.
1590   std::vector<uint64_t> InputFileOffsets;
1591   for (const auto &Entry : SortedFiles) {
1592     uint32_t &InputFileID = InputFileIDs[Entry.File];
1593     if (InputFileID != 0)
1594       continue; // already recorded this file.
1595
1596     // Record this entry's offset.
1597     InputFileOffsets.push_back(Stream.GetCurrentBitNo());
1598
1599     InputFileID = InputFileOffsets.size();
1600
1601     if (!Entry.IsSystemFile)
1602       ++UserFilesNum;
1603
1604     // Emit size/modification time for this file.
1605     // And whether this file was overridden.
1606     {
1607       RecordData::value_type Record[] = {
1608           INPUT_FILE,
1609           InputFileOffsets.size(),
1610           (uint64_t)Entry.File->getSize(),
1611           (uint64_t)getTimestampForOutput(Entry.File),
1612           Entry.BufferOverridden,
1613           Entry.IsTransient,
1614           Entry.IsTopLevelModuleMap};
1615
1616       // FIXME: The path should be taken from the FileEntryRef.
1617       EmitRecordWithPath(IFAbbrevCode, Record, Entry.File->getName());
1618     }
1619
1620     // Emit content hash for this file.
1621     {
1622       RecordData::value_type Record[] = {INPUT_FILE_HASH, Entry.ContentHash[0],
1623                                          Entry.ContentHash[1]};
1624       Stream.EmitRecordWithAbbrev(IFHAbbrevCode, Record);
1625     }
1626   }
1627
1628   Stream.ExitBlock();
1629
1630   // Create input file offsets abbreviation.
1631   auto OffsetsAbbrev = std::make_shared<BitCodeAbbrev>();
1632   OffsetsAbbrev->Add(BitCodeAbbrevOp(INPUT_FILE_OFFSETS));
1633   OffsetsAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // # input files
1634   OffsetsAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // # non-system
1635                                                                 //   input files
1636   OffsetsAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));   // Array
1637   unsigned OffsetsAbbrevCode = Stream.EmitAbbrev(std::move(OffsetsAbbrev));
1638
1639   // Write input file offsets.
1640   RecordData::value_type Record[] = {INPUT_FILE_OFFSETS,
1641                                      InputFileOffsets.size(), UserFilesNum};
1642   Stream.EmitRecordWithBlob(OffsetsAbbrevCode, Record, bytes(InputFileOffsets));
1643 }
1644
1645 //===----------------------------------------------------------------------===//
1646 // Source Manager Serialization
1647 //===----------------------------------------------------------------------===//
1648
1649 /// Create an abbreviation for the SLocEntry that refers to a
1650 /// file.
1651 static unsigned CreateSLocFileAbbrev(llvm::BitstreamWriter &Stream) {
1652   using namespace llvm;
1653
1654   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1655   Abbrev->Add(BitCodeAbbrevOp(SM_SLOC_FILE_ENTRY));
1656   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Offset
1657   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Include location
1658   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Characteristic
1659   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Line directives
1660   // FileEntry fields.
1661   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Input File ID
1662   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // NumCreatedFIDs
1663   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 24)); // FirstDeclIndex
1664   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // NumDecls
1665   return Stream.EmitAbbrev(std::move(Abbrev));
1666 }
1667
1668 /// Create an abbreviation for the SLocEntry that refers to a
1669 /// buffer.
1670 static unsigned CreateSLocBufferAbbrev(llvm::BitstreamWriter &Stream) {
1671   using namespace llvm;
1672
1673   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1674   Abbrev->Add(BitCodeAbbrevOp(SM_SLOC_BUFFER_ENTRY));
1675   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Offset
1676   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Include location
1677   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Characteristic
1678   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Line directives
1679   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Buffer name blob
1680   return Stream.EmitAbbrev(std::move(Abbrev));
1681 }
1682
1683 /// Create an abbreviation for the SLocEntry that refers to a
1684 /// buffer's blob.
1685 static unsigned CreateSLocBufferBlobAbbrev(llvm::BitstreamWriter &Stream,
1686                                            bool Compressed) {
1687   using namespace llvm;
1688
1689   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1690   Abbrev->Add(BitCodeAbbrevOp(Compressed ? SM_SLOC_BUFFER_BLOB_COMPRESSED
1691                                          : SM_SLOC_BUFFER_BLOB));
1692   if (Compressed)
1693     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Uncompressed size
1694   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Blob
1695   return Stream.EmitAbbrev(std::move(Abbrev));
1696 }
1697
1698 /// Create an abbreviation for the SLocEntry that refers to a macro
1699 /// expansion.
1700 static unsigned CreateSLocExpansionAbbrev(llvm::BitstreamWriter &Stream) {
1701   using namespace llvm;
1702
1703   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1704   Abbrev->Add(BitCodeAbbrevOp(SM_SLOC_EXPANSION_ENTRY));
1705   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Offset
1706   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Spelling location
1707   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Start location
1708   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // End location
1709   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Is token range
1710   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Token length
1711   return Stream.EmitAbbrev(std::move(Abbrev));
1712 }
1713
1714 /// Emit key length and data length as ULEB-encoded data, and return them as a
1715 /// pair.
1716 static std::pair<unsigned, unsigned>
1717 emitULEBKeyDataLength(unsigned KeyLen, unsigned DataLen, raw_ostream &Out) {
1718   llvm::encodeULEB128(KeyLen, Out);
1719   llvm::encodeULEB128(DataLen, Out);
1720   return std::make_pair(KeyLen, DataLen);
1721 }
1722
1723 namespace {
1724
1725   // Trait used for the on-disk hash table of header search information.
1726   class HeaderFileInfoTrait {
1727     ASTWriter &Writer;
1728
1729     // Keep track of the framework names we've used during serialization.
1730     SmallString<128> FrameworkStringData;
1731     llvm::StringMap<unsigned> FrameworkNameOffset;
1732
1733   public:
1734     HeaderFileInfoTrait(ASTWriter &Writer) : Writer(Writer) {}
1735
1736     struct key_type {
1737       StringRef Filename;
1738       off_t Size;
1739       time_t ModTime;
1740     };
1741     using key_type_ref = const key_type &;
1742
1743     using UnresolvedModule =
1744         llvm::PointerIntPair<Module *, 2, ModuleMap::ModuleHeaderRole>;
1745
1746     struct data_type {
1747       const HeaderFileInfo &HFI;
1748       ArrayRef<ModuleMap::KnownHeader> KnownHeaders;
1749       UnresolvedModule Unresolved;
1750     };
1751     using data_type_ref = const data_type &;
1752
1753     using hash_value_type = unsigned;
1754     using offset_type = unsigned;
1755
1756     hash_value_type ComputeHash(key_type_ref key) {
1757       // The hash is based only on size/time of the file, so that the reader can
1758       // match even when symlinking or excess path elements ("foo/../", "../")
1759       // change the form of the name. However, complete path is still the key.
1760       return llvm::hash_combine(key.Size, key.ModTime);
1761     }
1762
1763     std::pair<unsigned, unsigned>
1764     EmitKeyDataLength(raw_ostream& Out, key_type_ref key, data_type_ref Data) {
1765       unsigned KeyLen = key.Filename.size() + 1 + 8 + 8;
1766       unsigned DataLen = 1 + 4 + 4;
1767       for (auto ModInfo : Data.KnownHeaders)
1768         if (Writer.getLocalOrImportedSubmoduleID(ModInfo.getModule()))
1769           DataLen += 4;
1770       if (Data.Unresolved.getPointer())
1771         DataLen += 4;
1772       return emitULEBKeyDataLength(KeyLen, DataLen, Out);
1773     }
1774
1775     void EmitKey(raw_ostream& Out, key_type_ref key, unsigned KeyLen) {
1776       using namespace llvm::support;
1777
1778       endian::Writer LE(Out, little);
1779       LE.write<uint64_t>(key.Size);
1780       KeyLen -= 8;
1781       LE.write<uint64_t>(key.ModTime);
1782       KeyLen -= 8;
1783       Out.write(key.Filename.data(), KeyLen);
1784     }
1785
1786     void EmitData(raw_ostream &Out, key_type_ref key,
1787                   data_type_ref Data, unsigned DataLen) {
1788       using namespace llvm::support;
1789
1790       endian::Writer LE(Out, little);
1791       uint64_t Start = Out.tell(); (void)Start;
1792
1793       unsigned char Flags = (Data.HFI.isImport << 5)
1794                           | (Data.HFI.isPragmaOnce << 4)
1795                           | (Data.HFI.DirInfo << 1)
1796                           | Data.HFI.IndexHeaderMapHeader;
1797       LE.write<uint8_t>(Flags);
1798
1799       if (!Data.HFI.ControllingMacro)
1800         LE.write<uint32_t>(Data.HFI.ControllingMacroID);
1801       else
1802         LE.write<uint32_t>(Writer.getIdentifierRef(Data.HFI.ControllingMacro));
1803
1804       unsigned Offset = 0;
1805       if (!Data.HFI.Framework.empty()) {
1806         // If this header refers into a framework, save the framework name.
1807         llvm::StringMap<unsigned>::iterator Pos
1808           = FrameworkNameOffset.find(Data.HFI.Framework);
1809         if (Pos == FrameworkNameOffset.end()) {
1810           Offset = FrameworkStringData.size() + 1;
1811           FrameworkStringData.append(Data.HFI.Framework);
1812           FrameworkStringData.push_back(0);
1813
1814           FrameworkNameOffset[Data.HFI.Framework] = Offset;
1815         } else
1816           Offset = Pos->second;
1817       }
1818       LE.write<uint32_t>(Offset);
1819
1820       auto EmitModule = [&](Module *M, ModuleMap::ModuleHeaderRole Role) {
1821         if (uint32_t ModID = Writer.getLocalOrImportedSubmoduleID(M)) {
1822           uint32_t Value = (ModID << 2) | (unsigned)Role;
1823           assert((Value >> 2) == ModID && "overflow in header module info");
1824           LE.write<uint32_t>(Value);
1825         }
1826       };
1827
1828       // FIXME: If the header is excluded, we should write out some
1829       // record of that fact.
1830       for (auto ModInfo : Data.KnownHeaders)
1831         EmitModule(ModInfo.getModule(), ModInfo.getRole());
1832       if (Data.Unresolved.getPointer())
1833         EmitModule(Data.Unresolved.getPointer(), Data.Unresolved.getInt());
1834
1835       assert(Out.tell() - Start == DataLen && "Wrong data length");
1836     }
1837
1838     const char *strings_begin() const { return FrameworkStringData.begin(); }
1839     const char *strings_end() const { return FrameworkStringData.end(); }
1840   };
1841
1842 } // namespace
1843
1844 /// Write the header search block for the list of files that
1845 ///
1846 /// \param HS The header search structure to save.
1847 void ASTWriter::WriteHeaderSearch(const HeaderSearch &HS) {
1848   HeaderFileInfoTrait GeneratorTrait(*this);
1849   llvm::OnDiskChainedHashTableGenerator<HeaderFileInfoTrait> Generator;
1850   SmallVector<const char *, 4> SavedStrings;
1851   unsigned NumHeaderSearchEntries = 0;
1852
1853   // Find all unresolved headers for the current module. We generally will
1854   // have resolved them before we get here, but not necessarily: we might be
1855   // compiling a preprocessed module, where there is no requirement for the
1856   // original files to exist any more.
1857   const HeaderFileInfo Empty; // So we can take a reference.
1858   if (WritingModule) {
1859     llvm::SmallVector<Module *, 16> Worklist(1, WritingModule);
1860     while (!Worklist.empty()) {
1861       Module *M = Worklist.pop_back_val();
1862       // We don't care about headers in unimportable submodules.
1863       if (M->isUnimportable())
1864         continue;
1865
1866       // Map to disk files where possible, to pick up any missing stat
1867       // information. This also means we don't need to check the unresolved
1868       // headers list when emitting resolved headers in the first loop below.
1869       // FIXME: It'd be preferable to avoid doing this if we were given
1870       // sufficient stat information in the module map.
1871       HS.getModuleMap().resolveHeaderDirectives(M, /*File=*/llvm::None);
1872
1873       // If the file didn't exist, we can still create a module if we were given
1874       // enough information in the module map.
1875       for (auto U : M->MissingHeaders) {
1876         // Check that we were given enough information to build a module
1877         // without this file existing on disk.
1878         if (!U.Size || (!U.ModTime && IncludeTimestamps)) {
1879           PP->Diag(U.FileNameLoc, diag::err_module_no_size_mtime_for_header)
1880               << WritingModule->getFullModuleName() << U.Size.has_value()
1881               << U.FileName;
1882           continue;
1883         }
1884
1885         // Form the effective relative pathname for the file.
1886         SmallString<128> Filename(M->Directory->getName());
1887         llvm::sys::path::append(Filename, U.FileName);
1888         PreparePathForOutput(Filename);
1889
1890         StringRef FilenameDup = strdup(Filename.c_str());
1891         SavedStrings.push_back(FilenameDup.data());
1892
1893         HeaderFileInfoTrait::key_type Key = {
1894           FilenameDup, *U.Size, IncludeTimestamps ? *U.ModTime : 0
1895         };
1896         HeaderFileInfoTrait::data_type Data = {
1897           Empty, {}, {M, ModuleMap::headerKindToRole(U.Kind)}
1898         };
1899         // FIXME: Deal with cases where there are multiple unresolved header
1900         // directives in different submodules for the same header.
1901         Generator.insert(Key, Data, GeneratorTrait);
1902         ++NumHeaderSearchEntries;
1903       }
1904
1905       Worklist.append(M->submodule_begin(), M->submodule_end());
1906     }
1907   }
1908
1909   SmallVector<const FileEntry *, 16> FilesByUID;
1910   HS.getFileMgr().GetUniqueIDMapping(FilesByUID);
1911
1912   if (FilesByUID.size() > HS.header_file_size())
1913     FilesByUID.resize(HS.header_file_size());
1914
1915   for (unsigned UID = 0, LastUID = FilesByUID.size(); UID != LastUID; ++UID) {
1916     const FileEntry *File = FilesByUID[UID];
1917     if (!File)
1918       continue;
1919
1920     // Get the file info. This will load info from the external source if
1921     // necessary. Skip emitting this file if we have no information on it
1922     // as a header file (in which case HFI will be null) or if it hasn't
1923     // changed since it was loaded. Also skip it if it's for a modular header
1924     // from a different module; in that case, we rely on the module(s)
1925     // containing the header to provide this information.
1926     const HeaderFileInfo *HFI =
1927         HS.getExistingFileInfo(File, /*WantExternal*/!Chain);
1928     if (!HFI || (HFI->isModuleHeader && !HFI->isCompilingModuleHeader))
1929       continue;
1930
1931     // Massage the file path into an appropriate form.
1932     StringRef Filename = File->getName();
1933     SmallString<128> FilenameTmp(Filename);
1934     if (PreparePathForOutput(FilenameTmp)) {
1935       // If we performed any translation on the file name at all, we need to
1936       // save this string, since the generator will refer to it later.
1937       Filename = StringRef(strdup(FilenameTmp.c_str()));
1938       SavedStrings.push_back(Filename.data());
1939     }
1940
1941     HeaderFileInfoTrait::key_type Key = {
1942       Filename, File->getSize(), getTimestampForOutput(File)
1943     };
1944     HeaderFileInfoTrait::data_type Data = {
1945       *HFI, HS.getModuleMap().findResolvedModulesForHeader(File), {}
1946     };
1947     Generator.insert(Key, Data, GeneratorTrait);
1948     ++NumHeaderSearchEntries;
1949   }
1950
1951   // Create the on-disk hash table in a buffer.
1952   SmallString<4096> TableData;
1953   uint32_t BucketOffset;
1954   {
1955     using namespace llvm::support;
1956
1957     llvm::raw_svector_ostream Out(TableData);
1958     // Make sure that no bucket is at offset 0
1959     endian::write<uint32_t>(Out, 0, little);
1960     BucketOffset = Generator.Emit(Out, GeneratorTrait);
1961   }
1962
1963   // Create a blob abbreviation
1964   using namespace llvm;
1965
1966   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1967   Abbrev->Add(BitCodeAbbrevOp(HEADER_SEARCH_TABLE));
1968   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1969   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1970   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1971   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
1972   unsigned TableAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
1973
1974   // Write the header search table
1975   RecordData::value_type Record[] = {HEADER_SEARCH_TABLE, BucketOffset,
1976                                      NumHeaderSearchEntries, TableData.size()};
1977   TableData.append(GeneratorTrait.strings_begin(),GeneratorTrait.strings_end());
1978   Stream.EmitRecordWithBlob(TableAbbrev, Record, TableData);
1979
1980   // Free all of the strings we had to duplicate.
1981   for (unsigned I = 0, N = SavedStrings.size(); I != N; ++I)
1982     free(const_cast<char *>(SavedStrings[I]));
1983 }
1984
1985 static void emitBlob(llvm::BitstreamWriter &Stream, StringRef Blob,
1986                      unsigned SLocBufferBlobCompressedAbbrv,
1987                      unsigned SLocBufferBlobAbbrv) {
1988   using RecordDataType = ASTWriter::RecordData::value_type;
1989
1990   // Compress the buffer if possible. We expect that almost all PCM
1991   // consumers will not want its contents.
1992   SmallVector<uint8_t, 0> CompressedBuffer;
1993   if (llvm::compression::zlib::isAvailable()) {
1994     llvm::compression::zlib::compress(
1995         llvm::arrayRefFromStringRef(Blob.drop_back(1)), CompressedBuffer);
1996     RecordDataType Record[] = {SM_SLOC_BUFFER_BLOB_COMPRESSED, Blob.size() - 1};
1997     Stream.EmitRecordWithBlob(SLocBufferBlobCompressedAbbrv, Record,
1998                               llvm::toStringRef(CompressedBuffer));
1999     return;
2000   }
2001
2002   RecordDataType Record[] = {SM_SLOC_BUFFER_BLOB};
2003   Stream.EmitRecordWithBlob(SLocBufferBlobAbbrv, Record, Blob);
2004 }
2005
2006 /// Writes the block containing the serialized form of the
2007 /// source manager.
2008 ///
2009 /// TODO: We should probably use an on-disk hash table (stored in a
2010 /// blob), indexed based on the file name, so that we only create
2011 /// entries for files that we actually need. In the common case (no
2012 /// errors), we probably won't have to create file entries for any of
2013 /// the files in the AST.
2014 void ASTWriter::WriteSourceManagerBlock(SourceManager &SourceMgr,
2015                                         const Preprocessor &PP) {
2016   RecordData Record;
2017
2018   // Enter the source manager block.
2019   Stream.EnterSubblock(SOURCE_MANAGER_BLOCK_ID, 4);
2020   const uint64_t SourceManagerBlockOffset = Stream.GetCurrentBitNo();
2021
2022   // Abbreviations for the various kinds of source-location entries.
2023   unsigned SLocFileAbbrv = CreateSLocFileAbbrev(Stream);
2024   unsigned SLocBufferAbbrv = CreateSLocBufferAbbrev(Stream);
2025   unsigned SLocBufferBlobAbbrv = CreateSLocBufferBlobAbbrev(Stream, false);
2026   unsigned SLocBufferBlobCompressedAbbrv =
2027       CreateSLocBufferBlobAbbrev(Stream, true);
2028   unsigned SLocExpansionAbbrv = CreateSLocExpansionAbbrev(Stream);
2029
2030   // Write out the source location entry table. We skip the first
2031   // entry, which is always the same dummy entry.
2032   std::vector<uint32_t> SLocEntryOffsets;
2033   uint64_t SLocEntryOffsetsBase = Stream.GetCurrentBitNo();
2034   RecordData PreloadSLocs;
2035   SLocEntryOffsets.reserve(SourceMgr.local_sloc_entry_size() - 1);
2036   for (unsigned I = 1, N = SourceMgr.local_sloc_entry_size();
2037        I != N; ++I) {
2038     // Get this source location entry.
2039     const SrcMgr::SLocEntry *SLoc = &SourceMgr.getLocalSLocEntry(I);
2040     FileID FID = FileID::get(I);
2041     assert(&SourceMgr.getSLocEntry(FID) == SLoc);
2042
2043     // Record the offset of this source-location entry.
2044     uint64_t Offset = Stream.GetCurrentBitNo() - SLocEntryOffsetsBase;
2045     assert((Offset >> 32) == 0 && "SLocEntry offset too large");
2046     SLocEntryOffsets.push_back(Offset);
2047
2048     // Figure out which record code to use.
2049     unsigned Code;
2050     if (SLoc->isFile()) {
2051       const SrcMgr::ContentCache *Cache = &SLoc->getFile().getContentCache();
2052       if (Cache->OrigEntry) {
2053         Code = SM_SLOC_FILE_ENTRY;
2054       } else
2055         Code = SM_SLOC_BUFFER_ENTRY;
2056     } else
2057       Code = SM_SLOC_EXPANSION_ENTRY;
2058     Record.clear();
2059     Record.push_back(Code);
2060
2061     // Starting offset of this entry within this module, so skip the dummy.
2062     Record.push_back(SLoc->getOffset() - 2);
2063     if (SLoc->isFile()) {
2064       const SrcMgr::FileInfo &File = SLoc->getFile();
2065       const SrcMgr::ContentCache *Content = &File.getContentCache();
2066       if (Content->OrigEntry && !SkippedModuleMaps.empty() &&
2067           SkippedModuleMaps.find(Content->OrigEntry) !=
2068               SkippedModuleMaps.end()) {
2069         // Do not emit files that were not listed as inputs.
2070         continue;
2071       }
2072       AddSourceLocation(File.getIncludeLoc(), Record);
2073       Record.push_back(File.getFileCharacteristic()); // FIXME: stable encoding
2074       Record.push_back(File.hasLineDirectives());
2075
2076       bool EmitBlob = false;
2077       if (Content->OrigEntry) {
2078         assert(Content->OrigEntry == Content->ContentsEntry &&
2079                "Writing to AST an overridden file is not supported");
2080
2081         // The source location entry is a file. Emit input file ID.
2082         assert(InputFileIDs[Content->OrigEntry] != 0 && "Missed file entry");
2083         Record.push_back(InputFileIDs[Content->OrigEntry]);
2084
2085         Record.push_back(File.NumCreatedFIDs);
2086
2087         FileDeclIDsTy::iterator FDI = FileDeclIDs.find(FID);
2088         if (FDI != FileDeclIDs.end()) {
2089           Record.push_back(FDI->second->FirstDeclIndex);
2090           Record.push_back(FDI->second->DeclIDs.size());
2091         } else {
2092           Record.push_back(0);
2093           Record.push_back(0);
2094         }
2095
2096         Stream.EmitRecordWithAbbrev(SLocFileAbbrv, Record);
2097
2098         if (Content->BufferOverridden || Content->IsTransient)
2099           EmitBlob = true;
2100       } else {
2101         // The source location entry is a buffer. The blob associated
2102         // with this entry contains the contents of the buffer.
2103
2104         // We add one to the size so that we capture the trailing NULL
2105         // that is required by llvm::MemoryBuffer::getMemBuffer (on
2106         // the reader side).
2107         llvm::Optional<llvm::MemoryBufferRef> Buffer =
2108             Content->getBufferOrNone(PP.getDiagnostics(), PP.getFileManager());
2109         StringRef Name = Buffer ? Buffer->getBufferIdentifier() : "";
2110         Stream.EmitRecordWithBlob(SLocBufferAbbrv, Record,
2111                                   StringRef(Name.data(), Name.size() + 1));
2112         EmitBlob = true;
2113
2114         if (Name == "<built-in>")
2115           PreloadSLocs.push_back(SLocEntryOffsets.size());
2116       }
2117
2118       if (EmitBlob) {
2119         // Include the implicit terminating null character in the on-disk buffer
2120         // if we're writing it uncompressed.
2121         llvm::Optional<llvm::MemoryBufferRef> Buffer =
2122             Content->getBufferOrNone(PP.getDiagnostics(), PP.getFileManager());
2123         if (!Buffer)
2124           Buffer = llvm::MemoryBufferRef("<<<INVALID BUFFER>>>", "");
2125         StringRef Blob(Buffer->getBufferStart(), Buffer->getBufferSize() + 1);
2126         emitBlob(Stream, Blob, SLocBufferBlobCompressedAbbrv,
2127                  SLocBufferBlobAbbrv);
2128       }
2129     } else {
2130       // The source location entry is a macro expansion.
2131       const SrcMgr::ExpansionInfo &Expansion = SLoc->getExpansion();
2132       LocSeq::State Seq;
2133       AddSourceLocation(Expansion.getSpellingLoc(), Record, Seq);
2134       AddSourceLocation(Expansion.getExpansionLocStart(), Record, Seq);
2135       AddSourceLocation(Expansion.isMacroArgExpansion()
2136                             ? SourceLocation()
2137                             : Expansion.getExpansionLocEnd(),
2138                         Record, Seq);
2139       Record.push_back(Expansion.isExpansionTokenRange());
2140
2141       // Compute the token length for this macro expansion.
2142       SourceLocation::UIntTy NextOffset = SourceMgr.getNextLocalOffset();
2143       if (I + 1 != N)
2144         NextOffset = SourceMgr.getLocalSLocEntry(I + 1).getOffset();
2145       Record.push_back(NextOffset - SLoc->getOffset() - 1);
2146       Stream.EmitRecordWithAbbrev(SLocExpansionAbbrv, Record);
2147     }
2148   }
2149
2150   Stream.ExitBlock();
2151
2152   if (SLocEntryOffsets.empty())
2153     return;
2154
2155   // Write the source-location offsets table into the AST block. This
2156   // table is used for lazily loading source-location information.
2157   using namespace llvm;
2158
2159   auto Abbrev = std::make_shared<BitCodeAbbrev>();
2160   Abbrev->Add(BitCodeAbbrevOp(SOURCE_LOCATION_OFFSETS));
2161   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 16)); // # of slocs
2162   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 16)); // total size
2163   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 32)); // base offset
2164   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // offsets
2165   unsigned SLocOffsetsAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2166   {
2167     RecordData::value_type Record[] = {
2168         SOURCE_LOCATION_OFFSETS, SLocEntryOffsets.size(),
2169         SourceMgr.getNextLocalOffset() - 1 /* skip dummy */,
2170         SLocEntryOffsetsBase - SourceManagerBlockOffset};
2171     Stream.EmitRecordWithBlob(SLocOffsetsAbbrev, Record,
2172                               bytes(SLocEntryOffsets));
2173   }
2174   // Write the source location entry preloads array, telling the AST
2175   // reader which source locations entries it should load eagerly.
2176   Stream.EmitRecord(SOURCE_LOCATION_PRELOADS, PreloadSLocs);
2177
2178   // Write the line table. It depends on remapping working, so it must come
2179   // after the source location offsets.
2180   if (SourceMgr.hasLineTable()) {
2181     LineTableInfo &LineTable = SourceMgr.getLineTable();
2182
2183     Record.clear();
2184
2185     // Emit the needed file names.
2186     llvm::DenseMap<int, int> FilenameMap;
2187     FilenameMap[-1] = -1; // For unspecified filenames.
2188     for (const auto &L : LineTable) {
2189       if (L.first.ID < 0)
2190         continue;
2191       for (auto &LE : L.second) {
2192         if (FilenameMap.insert(std::make_pair(LE.FilenameID,
2193                                               FilenameMap.size() - 1)).second)
2194           AddPath(LineTable.getFilename(LE.FilenameID), Record);
2195       }
2196     }
2197     Record.push_back(0);
2198
2199     // Emit the line entries
2200     for (const auto &L : LineTable) {
2201       // Only emit entries for local files.
2202       if (L.first.ID < 0)
2203         continue;
2204
2205       // Emit the file ID
2206       Record.push_back(L.first.ID);
2207
2208       // Emit the line entries
2209       Record.push_back(L.second.size());
2210       for (const auto &LE : L.second) {
2211         Record.push_back(LE.FileOffset);
2212         Record.push_back(LE.LineNo);
2213         Record.push_back(FilenameMap[LE.FilenameID]);
2214         Record.push_back((unsigned)LE.FileKind);
2215         Record.push_back(LE.IncludeOffset);
2216       }
2217     }
2218
2219     Stream.EmitRecord(SOURCE_MANAGER_LINE_TABLE, Record);
2220   }
2221 }
2222
2223 //===----------------------------------------------------------------------===//
2224 // Preprocessor Serialization
2225 //===----------------------------------------------------------------------===//
2226
2227 static bool shouldIgnoreMacro(MacroDirective *MD, bool IsModule,
2228                               const Preprocessor &PP) {
2229   if (MacroInfo *MI = MD->getMacroInfo())
2230     if (MI->isBuiltinMacro())
2231       return true;
2232
2233   if (IsModule) {
2234     SourceLocation Loc = MD->getLocation();
2235     if (Loc.isInvalid())
2236       return true;
2237     if (PP.getSourceManager().getFileID(Loc) == PP.getPredefinesFileID())
2238       return true;
2239   }
2240
2241   return false;
2242 }
2243
2244 void ASTWriter::writeIncludedFiles(raw_ostream &Out, const Preprocessor &PP) {
2245   using namespace llvm::support;
2246
2247   const Preprocessor::IncludedFilesSet &IncludedFiles = PP.getIncludedFiles();
2248
2249   std::vector<uint32_t> IncludedInputFileIDs;
2250   IncludedInputFileIDs.reserve(IncludedFiles.size());
2251
2252   for (const FileEntry *File : IncludedFiles) {
2253     auto InputFileIt = InputFileIDs.find(File);
2254     if (InputFileIt == InputFileIDs.end())
2255       continue;
2256     IncludedInputFileIDs.push_back(InputFileIt->second);
2257   }
2258
2259   llvm::sort(IncludedInputFileIDs);
2260
2261   endian::Writer LE(Out, little);
2262   LE.write<uint32_t>(IncludedInputFileIDs.size());
2263   for (uint32_t ID : IncludedInputFileIDs)
2264     LE.write<uint32_t>(ID);
2265 }
2266
2267 /// Writes the block containing the serialized form of the
2268 /// preprocessor.
2269 void ASTWriter::WritePreprocessor(const Preprocessor &PP, bool IsModule) {
2270   uint64_t MacroOffsetsBase = Stream.GetCurrentBitNo();
2271
2272   PreprocessingRecord *PPRec = PP.getPreprocessingRecord();
2273   if (PPRec)
2274     WritePreprocessorDetail(*PPRec, MacroOffsetsBase);
2275
2276   RecordData Record;
2277   RecordData ModuleMacroRecord;
2278
2279   // If the preprocessor __COUNTER__ value has been bumped, remember it.
2280   if (PP.getCounterValue() != 0) {
2281     RecordData::value_type Record[] = {PP.getCounterValue()};
2282     Stream.EmitRecord(PP_COUNTER_VALUE, Record);
2283   }
2284
2285   // If we have a recorded #pragma assume_nonnull, remember it so it can be
2286   // replayed when the preamble terminates into the main file.
2287   SourceLocation AssumeNonNullLoc =
2288       PP.getPreambleRecordedPragmaAssumeNonNullLoc();
2289   if (AssumeNonNullLoc.isValid()) {
2290     assert(PP.isRecordingPreamble());
2291     AddSourceLocation(AssumeNonNullLoc, Record);
2292     Stream.EmitRecord(PP_ASSUME_NONNULL_LOC, Record);
2293     Record.clear();
2294   }
2295
2296   if (PP.isRecordingPreamble() && PP.hasRecordedPreamble()) {
2297     assert(!IsModule);
2298     auto SkipInfo = PP.getPreambleSkipInfo();
2299     if (SkipInfo) {
2300       Record.push_back(true);
2301       AddSourceLocation(SkipInfo->HashTokenLoc, Record);
2302       AddSourceLocation(SkipInfo->IfTokenLoc, Record);
2303       Record.push_back(SkipInfo->FoundNonSkipPortion);
2304       Record.push_back(SkipInfo->FoundElse);
2305       AddSourceLocation(SkipInfo->ElseLoc, Record);
2306     } else {
2307       Record.push_back(false);
2308     }
2309     for (const auto &Cond : PP.getPreambleConditionalStack()) {
2310       AddSourceLocation(Cond.IfLoc, Record);
2311       Record.push_back(Cond.WasSkipping);
2312       Record.push_back(Cond.FoundNonSkip);
2313       Record.push_back(Cond.FoundElse);
2314     }
2315     Stream.EmitRecord(PP_CONDITIONAL_STACK, Record);
2316     Record.clear();
2317   }
2318
2319   // Enter the preprocessor block.
2320   Stream.EnterSubblock(PREPROCESSOR_BLOCK_ID, 3);
2321
2322   // If the AST file contains __DATE__ or __TIME__ emit a warning about this.
2323   // FIXME: Include a location for the use, and say which one was used.
2324   if (PP.SawDateOrTime())
2325     PP.Diag(SourceLocation(), diag::warn_module_uses_date_time) << IsModule;
2326
2327   // Loop over all the macro directives that are live at the end of the file,
2328   // emitting each to the PP section.
2329
2330   // Construct the list of identifiers with macro directives that need to be
2331   // serialized.
2332   SmallVector<const IdentifierInfo *, 128> MacroIdentifiers;
2333   for (auto &Id : PP.getIdentifierTable())
2334     if (Id.second->hadMacroDefinition() &&
2335         (!Id.second->isFromAST() ||
2336          Id.second->hasChangedSinceDeserialization()))
2337       MacroIdentifiers.push_back(Id.second);
2338   // Sort the set of macro definitions that need to be serialized by the
2339   // name of the macro, to provide a stable ordering.
2340   llvm::sort(MacroIdentifiers, llvm::deref<std::less<>>());
2341
2342   // Emit the macro directives as a list and associate the offset with the
2343   // identifier they belong to.
2344   for (const IdentifierInfo *Name : MacroIdentifiers) {
2345     MacroDirective *MD = PP.getLocalMacroDirectiveHistory(Name);
2346     uint64_t StartOffset = Stream.GetCurrentBitNo() - MacroOffsetsBase;
2347     assert((StartOffset >> 32) == 0 && "Macro identifiers offset too large");
2348
2349     // Write out any exported module macros.
2350     bool EmittedModuleMacros = false;
2351     // C+=20 Header Units are compiled module interfaces, but they preserve
2352     // macros that are live (i.e. have a defined value) at the end of the
2353     // compilation.  So when writing a header unit, we preserve only the final
2354     // value of each macro (and discard any that are undefined).  Header units
2355     // do not have sub-modules (although they might import other header units).
2356     // PCH files, conversely, retain the history of each macro's define/undef
2357     // and of leaf macros in sub modules.
2358     if (IsModule && WritingModule->isHeaderUnit()) {
2359       // This is for the main TU when it is a C++20 header unit.
2360       // We preserve the final state of defined macros, and we do not emit ones
2361       // that are undefined.
2362       if (!MD || shouldIgnoreMacro(MD, IsModule, PP) ||
2363           MD->getKind() == MacroDirective::MD_Undefine)
2364         continue;
2365       AddSourceLocation(MD->getLocation(), Record);
2366       Record.push_back(MD->getKind());
2367       if (auto *DefMD = dyn_cast<DefMacroDirective>(MD)) {
2368         Record.push_back(getMacroRef(DefMD->getInfo(), Name));
2369       } else if (auto *VisMD = dyn_cast<VisibilityMacroDirective>(MD)) {
2370         Record.push_back(VisMD->isPublic());
2371       }
2372       ModuleMacroRecord.push_back(getSubmoduleID(WritingModule));
2373       ModuleMacroRecord.push_back(getMacroRef(MD->getMacroInfo(), Name));
2374       Stream.EmitRecord(PP_MODULE_MACRO, ModuleMacroRecord);
2375       ModuleMacroRecord.clear();
2376       EmittedModuleMacros = true;
2377     } else {
2378       // Emit the macro directives in reverse source order.
2379       for (; MD; MD = MD->getPrevious()) {
2380         // Once we hit an ignored macro, we're done: the rest of the chain
2381         // will all be ignored macros.
2382         if (shouldIgnoreMacro(MD, IsModule, PP))
2383           break;
2384         AddSourceLocation(MD->getLocation(), Record);
2385         Record.push_back(MD->getKind());
2386         if (auto *DefMD = dyn_cast<DefMacroDirective>(MD)) {
2387           Record.push_back(getMacroRef(DefMD->getInfo(), Name));
2388         } else if (auto *VisMD = dyn_cast<VisibilityMacroDirective>(MD)) {
2389           Record.push_back(VisMD->isPublic());
2390         }
2391       }
2392
2393       // We write out exported module macros for PCH as well.
2394       auto Leafs = PP.getLeafModuleMacros(Name);
2395       SmallVector<ModuleMacro *, 8> Worklist(Leafs.begin(), Leafs.end());
2396       llvm::DenseMap<ModuleMacro *, unsigned> Visits;
2397       while (!Worklist.empty()) {
2398         auto *Macro = Worklist.pop_back_val();
2399
2400         // Emit a record indicating this submodule exports this macro.
2401         ModuleMacroRecord.push_back(getSubmoduleID(Macro->getOwningModule()));
2402         ModuleMacroRecord.push_back(getMacroRef(Macro->getMacroInfo(), Name));
2403         for (auto *M : Macro->overrides())
2404           ModuleMacroRecord.push_back(getSubmoduleID(M->getOwningModule()));
2405
2406         Stream.EmitRecord(PP_MODULE_MACRO, ModuleMacroRecord);
2407         ModuleMacroRecord.clear();
2408
2409         // Enqueue overridden macros once we've visited all their ancestors.
2410         for (auto *M : Macro->overrides())
2411           if (++Visits[M] == M->getNumOverridingMacros())
2412             Worklist.push_back(M);
2413
2414         EmittedModuleMacros = true;
2415       }
2416     }
2417     if (Record.empty() && !EmittedModuleMacros)
2418       continue;
2419
2420     IdentMacroDirectivesOffsetMap[Name] = StartOffset;
2421     Stream.EmitRecord(PP_MACRO_DIRECTIVE_HISTORY, Record);
2422     Record.clear();
2423   }
2424
2425   /// Offsets of each of the macros into the bitstream, indexed by
2426   /// the local macro ID
2427   ///
2428   /// For each identifier that is associated with a macro, this map
2429   /// provides the offset into the bitstream where that macro is
2430   /// defined.
2431   std::vector<uint32_t> MacroOffsets;
2432
2433   for (unsigned I = 0, N = MacroInfosToEmit.size(); I != N; ++I) {
2434     const IdentifierInfo *Name = MacroInfosToEmit[I].Name;
2435     MacroInfo *MI = MacroInfosToEmit[I].MI;
2436     MacroID ID = MacroInfosToEmit[I].ID;
2437
2438     if (ID < FirstMacroID) {
2439       assert(0 && "Loaded MacroInfo entered MacroInfosToEmit ?");
2440       continue;
2441     }
2442
2443     // Record the local offset of this macro.
2444     unsigned Index = ID - FirstMacroID;
2445     if (Index >= MacroOffsets.size())
2446       MacroOffsets.resize(Index + 1);
2447
2448     uint64_t Offset = Stream.GetCurrentBitNo() - MacroOffsetsBase;
2449     assert((Offset >> 32) == 0 && "Macro offset too large");
2450     MacroOffsets[Index] = Offset;
2451
2452     AddIdentifierRef(Name, Record);
2453     AddSourceLocation(MI->getDefinitionLoc(), Record);
2454     AddSourceLocation(MI->getDefinitionEndLoc(), Record);
2455     Record.push_back(MI->isUsed());
2456     Record.push_back(MI->isUsedForHeaderGuard());
2457     Record.push_back(MI->getNumTokens());
2458     unsigned Code;
2459     if (MI->isObjectLike()) {
2460       Code = PP_MACRO_OBJECT_LIKE;
2461     } else {
2462       Code = PP_MACRO_FUNCTION_LIKE;
2463
2464       Record.push_back(MI->isC99Varargs());
2465       Record.push_back(MI->isGNUVarargs());
2466       Record.push_back(MI->hasCommaPasting());
2467       Record.push_back(MI->getNumParams());
2468       for (const IdentifierInfo *Param : MI->params())
2469         AddIdentifierRef(Param, Record);
2470     }
2471
2472     // If we have a detailed preprocessing record, record the macro definition
2473     // ID that corresponds to this macro.
2474     if (PPRec)
2475       Record.push_back(MacroDefinitions[PPRec->findMacroDefinition(MI)]);
2476
2477     Stream.EmitRecord(Code, Record);
2478     Record.clear();
2479
2480     // Emit the tokens array.
2481     for (unsigned TokNo = 0, e = MI->getNumTokens(); TokNo != e; ++TokNo) {
2482       // Note that we know that the preprocessor does not have any annotation
2483       // tokens in it because they are created by the parser, and thus can't
2484       // be in a macro definition.
2485       const Token &Tok = MI->getReplacementToken(TokNo);
2486       AddToken(Tok, Record);
2487       Stream.EmitRecord(PP_TOKEN, Record);
2488       Record.clear();
2489     }
2490     ++NumMacros;
2491   }
2492
2493   Stream.ExitBlock();
2494
2495   // Write the offsets table for macro IDs.
2496   using namespace llvm;
2497
2498   auto Abbrev = std::make_shared<BitCodeAbbrev>();
2499   Abbrev->Add(BitCodeAbbrevOp(MACRO_OFFSET));
2500   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // # of macros
2501   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // first ID
2502   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 32));   // base offset
2503   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2504
2505   unsigned MacroOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2506   {
2507     RecordData::value_type Record[] = {MACRO_OFFSET, MacroOffsets.size(),
2508                                        FirstMacroID - NUM_PREDEF_MACRO_IDS,
2509                                        MacroOffsetsBase - ASTBlockStartOffset};
2510     Stream.EmitRecordWithBlob(MacroOffsetAbbrev, Record, bytes(MacroOffsets));
2511   }
2512
2513   {
2514     auto Abbrev = std::make_shared<BitCodeAbbrev>();
2515     Abbrev->Add(BitCodeAbbrevOp(PP_INCLUDED_FILES));
2516     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2517     unsigned IncludedFilesAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2518
2519     SmallString<2048> Buffer;
2520     raw_svector_ostream Out(Buffer);
2521     writeIncludedFiles(Out, PP);
2522     RecordData::value_type Record[] = {PP_INCLUDED_FILES};
2523     Stream.EmitRecordWithBlob(IncludedFilesAbbrev, Record, Buffer.data(),
2524                               Buffer.size());
2525   }
2526 }
2527
2528 void ASTWriter::WritePreprocessorDetail(PreprocessingRecord &PPRec,
2529                                         uint64_t MacroOffsetsBase) {
2530   if (PPRec.local_begin() == PPRec.local_end())
2531     return;
2532
2533   SmallVector<PPEntityOffset, 64> PreprocessedEntityOffsets;
2534
2535   // Enter the preprocessor block.
2536   Stream.EnterSubblock(PREPROCESSOR_DETAIL_BLOCK_ID, 3);
2537
2538   // If the preprocessor has a preprocessing record, emit it.
2539   unsigned NumPreprocessingRecords = 0;
2540   using namespace llvm;
2541
2542   // Set up the abbreviation for
2543   unsigned InclusionAbbrev = 0;
2544   {
2545     auto Abbrev = std::make_shared<BitCodeAbbrev>();
2546     Abbrev->Add(BitCodeAbbrevOp(PPD_INCLUSION_DIRECTIVE));
2547     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // filename length
2548     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // in quotes
2549     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // kind
2550     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // imported module
2551     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2552     InclusionAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2553   }
2554
2555   unsigned FirstPreprocessorEntityID
2556     = (Chain ? PPRec.getNumLoadedPreprocessedEntities() : 0)
2557     + NUM_PREDEF_PP_ENTITY_IDS;
2558   unsigned NextPreprocessorEntityID = FirstPreprocessorEntityID;
2559   RecordData Record;
2560   for (PreprocessingRecord::iterator E = PPRec.local_begin(),
2561                                   EEnd = PPRec.local_end();
2562        E != EEnd;
2563        (void)++E, ++NumPreprocessingRecords, ++NextPreprocessorEntityID) {
2564     Record.clear();
2565
2566     uint64_t Offset = Stream.GetCurrentBitNo() - MacroOffsetsBase;
2567     assert((Offset >> 32) == 0 && "Preprocessed entity offset too large");
2568     PreprocessedEntityOffsets.push_back(
2569         PPEntityOffset((*E)->getSourceRange(), Offset));
2570
2571     if (auto *MD = dyn_cast<MacroDefinitionRecord>(*E)) {
2572       // Record this macro definition's ID.
2573       MacroDefinitions[MD] = NextPreprocessorEntityID;
2574
2575       AddIdentifierRef(MD->getName(), Record);
2576       Stream.EmitRecord(PPD_MACRO_DEFINITION, Record);
2577       continue;
2578     }
2579
2580     if (auto *ME = dyn_cast<MacroExpansion>(*E)) {
2581       Record.push_back(ME->isBuiltinMacro());
2582       if (ME->isBuiltinMacro())
2583         AddIdentifierRef(ME->getName(), Record);
2584       else
2585         Record.push_back(MacroDefinitions[ME->getDefinition()]);
2586       Stream.EmitRecord(PPD_MACRO_EXPANSION, Record);
2587       continue;
2588     }
2589
2590     if (auto *ID = dyn_cast<InclusionDirective>(*E)) {
2591       Record.push_back(PPD_INCLUSION_DIRECTIVE);
2592       Record.push_back(ID->getFileName().size());
2593       Record.push_back(ID->wasInQuotes());
2594       Record.push_back(static_cast<unsigned>(ID->getKind()));
2595       Record.push_back(ID->importedModule());
2596       SmallString<64> Buffer;
2597       Buffer += ID->getFileName();
2598       // Check that the FileEntry is not null because it was not resolved and
2599       // we create a PCH even with compiler errors.
2600       if (ID->getFile())
2601         Buffer += ID->getFile()->getName();
2602       Stream.EmitRecordWithBlob(InclusionAbbrev, Record, Buffer);
2603       continue;
2604     }
2605
2606     llvm_unreachable("Unhandled PreprocessedEntity in ASTWriter");
2607   }
2608   Stream.ExitBlock();
2609
2610   // Write the offsets table for the preprocessing record.
2611   if (NumPreprocessingRecords > 0) {
2612     assert(PreprocessedEntityOffsets.size() == NumPreprocessingRecords);
2613
2614     // Write the offsets table for identifier IDs.
2615     using namespace llvm;
2616
2617     auto Abbrev = std::make_shared<BitCodeAbbrev>();
2618     Abbrev->Add(BitCodeAbbrevOp(PPD_ENTITIES_OFFSETS));
2619     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // first pp entity
2620     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2621     unsigned PPEOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2622
2623     RecordData::value_type Record[] = {PPD_ENTITIES_OFFSETS,
2624                                        FirstPreprocessorEntityID -
2625                                            NUM_PREDEF_PP_ENTITY_IDS};
2626     Stream.EmitRecordWithBlob(PPEOffsetAbbrev, Record,
2627                               bytes(PreprocessedEntityOffsets));
2628   }
2629
2630   // Write the skipped region table for the preprocessing record.
2631   ArrayRef<SourceRange> SkippedRanges = PPRec.getSkippedRanges();
2632   if (SkippedRanges.size() > 0) {
2633     std::vector<PPSkippedRange> SerializedSkippedRanges;
2634     SerializedSkippedRanges.reserve(SkippedRanges.size());
2635     for (auto const& Range : SkippedRanges)
2636       SerializedSkippedRanges.emplace_back(Range);
2637
2638     using namespace llvm;
2639     auto Abbrev = std::make_shared<BitCodeAbbrev>();
2640     Abbrev->Add(BitCodeAbbrevOp(PPD_SKIPPED_RANGES));
2641     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2642     unsigned PPESkippedRangeAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2643
2644     Record.clear();
2645     Record.push_back(PPD_SKIPPED_RANGES);
2646     Stream.EmitRecordWithBlob(PPESkippedRangeAbbrev, Record,
2647                               bytes(SerializedSkippedRanges));
2648   }
2649 }
2650
2651 unsigned ASTWriter::getLocalOrImportedSubmoduleID(const Module *Mod) {
2652   if (!Mod)
2653     return 0;
2654
2655   auto Known = SubmoduleIDs.find(Mod);
2656   if (Known != SubmoduleIDs.end())
2657     return Known->second;
2658
2659   auto *Top = Mod->getTopLevelModule();
2660   if (Top != WritingModule &&
2661       (getLangOpts().CompilingPCH ||
2662        !Top->fullModuleNameIs(StringRef(getLangOpts().CurrentModule))))
2663     return 0;
2664
2665   return SubmoduleIDs[Mod] = NextSubmoduleID++;
2666 }
2667
2668 unsigned ASTWriter::getSubmoduleID(Module *Mod) {
2669   // FIXME: This can easily happen, if we have a reference to a submodule that
2670   // did not result in us loading a module file for that submodule. For
2671   // instance, a cross-top-level-module 'conflict' declaration will hit this.
2672   unsigned ID = getLocalOrImportedSubmoduleID(Mod);
2673   assert((ID || !Mod) &&
2674          "asked for module ID for non-local, non-imported module");
2675   return ID;
2676 }
2677
2678 /// Compute the number of modules within the given tree (including the
2679 /// given module).
2680 static unsigned getNumberOfModules(Module *Mod) {
2681   unsigned ChildModules = 0;
2682   for (auto Sub = Mod->submodule_begin(), SubEnd = Mod->submodule_end();
2683        Sub != SubEnd; ++Sub)
2684     ChildModules += getNumberOfModules(*Sub);
2685
2686   return ChildModules + 1;
2687 }
2688
2689 void ASTWriter::WriteSubmodules(Module *WritingModule) {
2690   // Enter the submodule description block.
2691   Stream.EnterSubblock(SUBMODULE_BLOCK_ID, /*bits for abbreviations*/5);
2692
2693   // Write the abbreviations needed for the submodules block.
2694   using namespace llvm;
2695
2696   auto Abbrev = std::make_shared<BitCodeAbbrev>();
2697   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_DEFINITION));
2698   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ID
2699   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Parent
2700   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Kind
2701   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFramework
2702   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsExplicit
2703   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsSystem
2704   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsExternC
2705   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InferSubmodules...
2706   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InferExplicit...
2707   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InferExportWild...
2708   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ConfigMacrosExh...
2709   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ModuleMapIsPriv...
2710   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2711   unsigned DefinitionAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2712
2713   Abbrev = std::make_shared<BitCodeAbbrev>();
2714   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_UMBRELLA_HEADER));
2715   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2716   unsigned UmbrellaAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2717
2718   Abbrev = std::make_shared<BitCodeAbbrev>();
2719   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_HEADER));
2720   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2721   unsigned HeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2722
2723   Abbrev = std::make_shared<BitCodeAbbrev>();
2724   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_TOPHEADER));
2725   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2726   unsigned TopHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2727
2728   Abbrev = std::make_shared<BitCodeAbbrev>();
2729   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_UMBRELLA_DIR));
2730   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2731   unsigned UmbrellaDirAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2732
2733   Abbrev = std::make_shared<BitCodeAbbrev>();
2734   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_REQUIRES));
2735   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // State
2736   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));     // Feature
2737   unsigned RequiresAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2738
2739   Abbrev = std::make_shared<BitCodeAbbrev>();
2740   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_EXCLUDED_HEADER));
2741   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2742   unsigned ExcludedHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2743
2744   Abbrev = std::make_shared<BitCodeAbbrev>();
2745   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_TEXTUAL_HEADER));
2746   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2747   unsigned TextualHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2748
2749   Abbrev = std::make_shared<BitCodeAbbrev>();
2750   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_PRIVATE_HEADER));
2751   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2752   unsigned PrivateHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2753
2754   Abbrev = std::make_shared<BitCodeAbbrev>();
2755   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_PRIVATE_TEXTUAL_HEADER));
2756   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2757   unsigned PrivateTextualHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2758
2759   Abbrev = std::make_shared<BitCodeAbbrev>();
2760   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_LINK_LIBRARY));
2761   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFramework
2762   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));     // Name
2763   unsigned LinkLibraryAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2764
2765   Abbrev = std::make_shared<BitCodeAbbrev>();
2766   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_CONFIG_MACRO));
2767   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));    // Macro name
2768   unsigned ConfigMacroAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2769
2770   Abbrev = std::make_shared<BitCodeAbbrev>();
2771   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_CONFLICT));
2772   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));  // Other module
2773   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));    // Message
2774   unsigned ConflictAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2775
2776   Abbrev = std::make_shared<BitCodeAbbrev>();
2777   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_EXPORT_AS));
2778   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));    // Macro name
2779   unsigned ExportAsAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2780
2781   // Write the submodule metadata block.
2782   RecordData::value_type Record[] = {
2783       getNumberOfModules(WritingModule),
2784       FirstSubmoduleID - NUM_PREDEF_SUBMODULE_IDS};
2785   Stream.EmitRecord(SUBMODULE_METADATA, Record);
2786
2787   // Write all of the submodules.
2788   std::queue<Module *> Q;
2789   Q.push(WritingModule);
2790   while (!Q.empty()) {
2791     Module *Mod = Q.front();
2792     Q.pop();
2793     unsigned ID = getSubmoduleID(Mod);
2794
2795     uint64_t ParentID = 0;
2796     if (Mod->Parent) {
2797       assert(SubmoduleIDs[Mod->Parent] && "Submodule parent not written?");
2798       ParentID = SubmoduleIDs[Mod->Parent];
2799     }
2800
2801     // Emit the definition of the block.
2802     {
2803       RecordData::value_type Record[] = {SUBMODULE_DEFINITION,
2804                                          ID,
2805                                          ParentID,
2806                                          (RecordData::value_type)Mod->Kind,
2807                                          Mod->IsFramework,
2808                                          Mod->IsExplicit,
2809                                          Mod->IsSystem,
2810                                          Mod->IsExternC,
2811                                          Mod->InferSubmodules,
2812                                          Mod->InferExplicitSubmodules,
2813                                          Mod->InferExportWildcard,
2814                                          Mod->ConfigMacrosExhaustive,
2815                                          Mod->ModuleMapIsPrivate};
2816       Stream.EmitRecordWithBlob(DefinitionAbbrev, Record, Mod->Name);
2817     }
2818
2819     // Emit the requirements.
2820     for (const auto &R : Mod->Requirements) {
2821       RecordData::value_type Record[] = {SUBMODULE_REQUIRES, R.second};
2822       Stream.EmitRecordWithBlob(RequiresAbbrev, Record, R.first);
2823     }
2824
2825     // Emit the umbrella header, if there is one.
2826     if (auto UmbrellaHeader = Mod->getUmbrellaHeader()) {
2827       RecordData::value_type Record[] = {SUBMODULE_UMBRELLA_HEADER};
2828       Stream.EmitRecordWithBlob(UmbrellaAbbrev, Record,
2829                                 UmbrellaHeader.NameAsWritten);
2830     } else if (auto UmbrellaDir = Mod->getUmbrellaDir()) {
2831       RecordData::value_type Record[] = {SUBMODULE_UMBRELLA_DIR};
2832       Stream.EmitRecordWithBlob(UmbrellaDirAbbrev, Record,
2833                                 UmbrellaDir.NameAsWritten);
2834     }
2835
2836     // Emit the headers.
2837     struct {
2838       unsigned RecordKind;
2839       unsigned Abbrev;
2840       Module::HeaderKind HeaderKind;
2841     } HeaderLists[] = {
2842       {SUBMODULE_HEADER, HeaderAbbrev, Module::HK_Normal},
2843       {SUBMODULE_TEXTUAL_HEADER, TextualHeaderAbbrev, Module::HK_Textual},
2844       {SUBMODULE_PRIVATE_HEADER, PrivateHeaderAbbrev, Module::HK_Private},
2845       {SUBMODULE_PRIVATE_TEXTUAL_HEADER, PrivateTextualHeaderAbbrev,
2846         Module::HK_PrivateTextual},
2847       {SUBMODULE_EXCLUDED_HEADER, ExcludedHeaderAbbrev, Module::HK_Excluded}
2848     };
2849     for (auto &HL : HeaderLists) {
2850       RecordData::value_type Record[] = {HL.RecordKind};
2851       for (auto &H : Mod->Headers[HL.HeaderKind])
2852         Stream.EmitRecordWithBlob(HL.Abbrev, Record, H.NameAsWritten);
2853     }
2854
2855     // Emit the top headers.
2856     {
2857       auto TopHeaders = Mod->getTopHeaders(PP->getFileManager());
2858       RecordData::value_type Record[] = {SUBMODULE_TOPHEADER};
2859       for (auto *H : TopHeaders) {
2860         SmallString<128> HeaderName(H->getName());
2861         PreparePathForOutput(HeaderName);
2862         Stream.EmitRecordWithBlob(TopHeaderAbbrev, Record, HeaderName);
2863       }
2864     }
2865
2866     // Emit the imports.
2867     if (!Mod->Imports.empty()) {
2868       RecordData Record;
2869       for (auto *I : Mod->Imports)
2870         Record.push_back(getSubmoduleID(I));
2871       Stream.EmitRecord(SUBMODULE_IMPORTS, Record);
2872     }
2873
2874     // Emit the modules affecting compilation that were not imported.
2875     if (!Mod->AffectingModules.empty()) {
2876       RecordData Record;
2877       for (auto *I : Mod->AffectingModules)
2878         Record.push_back(getSubmoduleID(I));
2879       Stream.EmitRecord(SUBMODULE_AFFECTING_MODULES, Record);
2880     }
2881
2882     // Emit the exports.
2883     if (!Mod->Exports.empty()) {
2884       RecordData Record;
2885       for (const auto &E : Mod->Exports) {
2886         // FIXME: This may fail; we don't require that all exported modules
2887         // are local or imported.
2888         Record.push_back(getSubmoduleID(E.getPointer()));
2889         Record.push_back(E.getInt());
2890       }
2891       Stream.EmitRecord(SUBMODULE_EXPORTS, Record);
2892     }
2893
2894     //FIXME: How do we emit the 'use'd modules?  They may not be submodules.
2895     // Might be unnecessary as use declarations are only used to build the
2896     // module itself.
2897
2898     // TODO: Consider serializing undeclared uses of modules.
2899
2900     // Emit the link libraries.
2901     for (const auto &LL : Mod->LinkLibraries) {
2902       RecordData::value_type Record[] = {SUBMODULE_LINK_LIBRARY,
2903                                          LL.IsFramework};
2904       Stream.EmitRecordWithBlob(LinkLibraryAbbrev, Record, LL.Library);
2905     }
2906
2907     // Emit the conflicts.
2908     for (const auto &C : Mod->Conflicts) {
2909       // FIXME: This may fail; we don't require that all conflicting modules
2910       // are local or imported.
2911       RecordData::value_type Record[] = {SUBMODULE_CONFLICT,
2912                                          getSubmoduleID(C.Other)};
2913       Stream.EmitRecordWithBlob(ConflictAbbrev, Record, C.Message);
2914     }
2915
2916     // Emit the configuration macros.
2917     for (const auto &CM : Mod->ConfigMacros) {
2918       RecordData::value_type Record[] = {SUBMODULE_CONFIG_MACRO};
2919       Stream.EmitRecordWithBlob(ConfigMacroAbbrev, Record, CM);
2920     }
2921
2922     // Emit the initializers, if any.
2923     RecordData Inits;
2924     for (Decl *D : Context->getModuleInitializers(Mod))
2925       Inits.push_back(GetDeclRef(D));
2926     if (!Inits.empty())
2927       Stream.EmitRecord(SUBMODULE_INITIALIZERS, Inits);
2928
2929     // Emit the name of the re-exported module, if any.
2930     if (!Mod->ExportAsModule.empty()) {
2931       RecordData::value_type Record[] = {SUBMODULE_EXPORT_AS};
2932       Stream.EmitRecordWithBlob(ExportAsAbbrev, Record, Mod->ExportAsModule);
2933     }
2934
2935     // Queue up the submodules of this module.
2936     for (auto *M : Mod->submodules())
2937       Q.push(M);
2938   }
2939
2940   Stream.ExitBlock();
2941
2942   assert((NextSubmoduleID - FirstSubmoduleID ==
2943           getNumberOfModules(WritingModule)) &&
2944          "Wrong # of submodules; found a reference to a non-local, "
2945          "non-imported submodule?");
2946 }
2947
2948 void ASTWriter::WritePragmaDiagnosticMappings(const DiagnosticsEngine &Diag,
2949                                               bool isModule) {
2950   llvm::SmallDenseMap<const DiagnosticsEngine::DiagState *, unsigned, 64>
2951       DiagStateIDMap;
2952   unsigned CurrID = 0;
2953   RecordData Record;
2954
2955   auto EncodeDiagStateFlags =
2956       [](const DiagnosticsEngine::DiagState *DS) -> unsigned {
2957     unsigned Result = (unsigned)DS->ExtBehavior;
2958     for (unsigned Val :
2959          {(unsigned)DS->IgnoreAllWarnings, (unsigned)DS->EnableAllWarnings,
2960           (unsigned)DS->WarningsAsErrors, (unsigned)DS->ErrorsAsFatal,
2961           (unsigned)DS->SuppressSystemWarnings})
2962       Result = (Result << 1) | Val;
2963     return Result;
2964   };
2965
2966   unsigned Flags = EncodeDiagStateFlags(Diag.DiagStatesByLoc.FirstDiagState);
2967   Record.push_back(Flags);
2968
2969   auto AddDiagState = [&](const DiagnosticsEngine::DiagState *State,
2970                           bool IncludeNonPragmaStates) {
2971     // Ensure that the diagnostic state wasn't modified since it was created.
2972     // We will not correctly round-trip this information otherwise.
2973     assert(Flags == EncodeDiagStateFlags(State) &&
2974            "diag state flags vary in single AST file");
2975
2976     unsigned &DiagStateID = DiagStateIDMap[State];
2977     Record.push_back(DiagStateID);
2978
2979     if (DiagStateID == 0) {
2980       DiagStateID = ++CurrID;
2981
2982       // Add a placeholder for the number of mappings.
2983       auto SizeIdx = Record.size();
2984       Record.emplace_back();
2985       for (const auto &I : *State) {
2986         if (I.second.isPragma() || IncludeNonPragmaStates) {
2987           Record.push_back(I.first);
2988           Record.push_back(I.second.serialize());
2989         }
2990       }
2991       // Update the placeholder.
2992       Record[SizeIdx] = (Record.size() - SizeIdx) / 2;
2993     }
2994   };
2995
2996   AddDiagState(Diag.DiagStatesByLoc.FirstDiagState, isModule);
2997
2998   // Reserve a spot for the number of locations with state transitions.
2999   auto NumLocationsIdx = Record.size();
3000   Record.emplace_back();
3001
3002   // Emit the state transitions.
3003   unsigned NumLocations = 0;
3004   for (auto &FileIDAndFile : Diag.DiagStatesByLoc.Files) {
3005     if (!FileIDAndFile.first.isValid() ||
3006         !FileIDAndFile.second.HasLocalTransitions)
3007       continue;
3008     ++NumLocations;
3009
3010     SourceLocation Loc = Diag.SourceMgr->getComposedLoc(FileIDAndFile.first, 0);
3011     assert(!Loc.isInvalid() && "start loc for valid FileID is invalid");
3012     AddSourceLocation(Loc, Record);
3013
3014     Record.push_back(FileIDAndFile.second.StateTransitions.size());
3015     for (auto &StatePoint : FileIDAndFile.second.StateTransitions) {
3016       Record.push_back(StatePoint.Offset);
3017       AddDiagState(StatePoint.State, false);
3018     }
3019   }
3020
3021   // Backpatch the number of locations.
3022   Record[NumLocationsIdx] = NumLocations;
3023
3024   // Emit CurDiagStateLoc.  Do it last in order to match source order.
3025   //
3026   // This also protects against a hypothetical corner case with simulating
3027   // -Werror settings for implicit modules in the ASTReader, where reading
3028   // CurDiagState out of context could change whether warning pragmas are
3029   // treated as errors.
3030   AddSourceLocation(Diag.DiagStatesByLoc.CurDiagStateLoc, Record);
3031   AddDiagState(Diag.DiagStatesByLoc.CurDiagState, false);
3032
3033   Stream.EmitRecord(DIAG_PRAGMA_MAPPINGS, Record);
3034 }
3035
3036 //===----------------------------------------------------------------------===//
3037 // Type Serialization
3038 //===----------------------------------------------------------------------===//
3039
3040 /// Write the representation of a type to the AST stream.
3041 void ASTWriter::WriteType(QualType T) {
3042   TypeIdx &IdxRef = TypeIdxs[T];
3043   if (IdxRef.getIndex() == 0) // we haven't seen this type before.
3044     IdxRef = TypeIdx(NextTypeID++);
3045   TypeIdx Idx = IdxRef;
3046
3047   assert(Idx.getIndex() >= FirstTypeID && "Re-writing a type from a prior AST");
3048
3049   // Emit the type's representation.
3050   uint64_t Offset = ASTTypeWriter(*this).write(T) - DeclTypesBlockStartOffset;
3051
3052   // Record the offset for this type.
3053   unsigned Index = Idx.getIndex() - FirstTypeID;
3054   if (TypeOffsets.size() == Index)
3055     TypeOffsets.emplace_back(Offset);
3056   else if (TypeOffsets.size() < Index) {
3057     TypeOffsets.resize(Index + 1);
3058     TypeOffsets[Index].setBitOffset(Offset);
3059   } else {
3060     llvm_unreachable("Types emitted in wrong order");
3061   }
3062 }
3063
3064 //===----------------------------------------------------------------------===//
3065 // Declaration Serialization
3066 //===----------------------------------------------------------------------===//
3067
3068 /// Write the block containing all of the declaration IDs
3069 /// lexically declared within the given DeclContext.
3070 ///
3071 /// \returns the offset of the DECL_CONTEXT_LEXICAL block within the
3072 /// bitstream, or 0 if no block was written.
3073 uint64_t ASTWriter::WriteDeclContextLexicalBlock(ASTContext &Context,
3074                                                  DeclContext *DC) {
3075   if (DC->decls_empty())
3076     return 0;
3077
3078   uint64_t Offset = Stream.GetCurrentBitNo();
3079   SmallVector<uint32_t, 128> KindDeclPairs;
3080   for (const auto *D : DC->decls()) {
3081     KindDeclPairs.push_back(D->getKind());
3082     KindDeclPairs.push_back(GetDeclRef(D));
3083   }
3084
3085   ++NumLexicalDeclContexts;
3086   RecordData::value_type Record[] = {DECL_CONTEXT_LEXICAL};
3087   Stream.EmitRecordWithBlob(DeclContextLexicalAbbrev, Record,
3088                             bytes(KindDeclPairs));
3089   return Offset;
3090 }
3091
3092 void ASTWriter::WriteTypeDeclOffsets() {
3093   using namespace llvm;
3094
3095   // Write the type offsets array
3096   auto Abbrev = std::make_shared<BitCodeAbbrev>();
3097   Abbrev->Add(BitCodeAbbrevOp(TYPE_OFFSET));
3098   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // # of types
3099   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // base type index
3100   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // types block
3101   unsigned TypeOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3102   {
3103     RecordData::value_type Record[] = {TYPE_OFFSET, TypeOffsets.size(),
3104                                        FirstTypeID - NUM_PREDEF_TYPE_IDS};
3105     Stream.EmitRecordWithBlob(TypeOffsetAbbrev, Record, bytes(TypeOffsets));
3106   }
3107
3108   // Write the declaration offsets array
3109   Abbrev = std::make_shared<BitCodeAbbrev>();
3110   Abbrev->Add(BitCodeAbbrevOp(DECL_OFFSET));
3111   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // # of declarations
3112   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // base decl ID
3113   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // declarations block
3114   unsigned DeclOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3115   {
3116     RecordData::value_type Record[] = {DECL_OFFSET, DeclOffsets.size(),
3117                                        FirstDeclID - NUM_PREDEF_DECL_IDS};
3118     Stream.EmitRecordWithBlob(DeclOffsetAbbrev, Record, bytes(DeclOffsets));
3119   }
3120 }
3121
3122 void ASTWriter::WriteFileDeclIDsMap() {
3123   using namespace llvm;
3124
3125   SmallVector<std::pair<FileID, DeclIDInFileInfo *>, 64> SortedFileDeclIDs;
3126   SortedFileDeclIDs.reserve(FileDeclIDs.size());
3127   for (const auto &P : FileDeclIDs)
3128     SortedFileDeclIDs.push_back(std::make_pair(P.first, P.second.get()));
3129   llvm::sort(SortedFileDeclIDs, llvm::less_first());
3130
3131   // Join the vectors of DeclIDs from all files.
3132   SmallVector<DeclID, 256> FileGroupedDeclIDs;
3133   for (auto &FileDeclEntry : SortedFileDeclIDs) {
3134     DeclIDInFileInfo &Info = *FileDeclEntry.second;
3135     Info.FirstDeclIndex = FileGroupedDeclIDs.size();
3136     llvm::stable_sort(Info.DeclIDs);
3137     for (auto &LocDeclEntry : Info.DeclIDs)
3138       FileGroupedDeclIDs.push_back(LocDeclEntry.second);
3139   }
3140
3141   auto Abbrev = std::make_shared<BitCodeAbbrev>();
3142   Abbrev->Add(BitCodeAbbrevOp(FILE_SORTED_DECLS));
3143   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
3144   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3145   unsigned AbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
3146   RecordData::value_type Record[] = {FILE_SORTED_DECLS,
3147                                      FileGroupedDeclIDs.size()};
3148   Stream.EmitRecordWithBlob(AbbrevCode, Record, bytes(FileGroupedDeclIDs));
3149 }
3150
3151 void ASTWriter::WriteComments() {
3152   Stream.EnterSubblock(COMMENTS_BLOCK_ID, 3);
3153   auto _ = llvm::make_scope_exit([this] { Stream.ExitBlock(); });
3154   if (!PP->getPreprocessorOpts().WriteCommentListToPCH)
3155     return;
3156   RecordData Record;
3157   for (const auto &FO : Context->Comments.OrderedComments) {
3158     for (const auto &OC : FO.second) {
3159       const RawComment *I = OC.second;
3160       Record.clear();
3161       AddSourceRange(I->getSourceRange(), Record);
3162       Record.push_back(I->getKind());
3163       Record.push_back(I->isTrailingComment());
3164       Record.push_back(I->isAlmostTrailingComment());
3165       Stream.EmitRecord(COMMENTS_RAW_COMMENT, Record);
3166     }
3167   }
3168 }
3169
3170 //===----------------------------------------------------------------------===//
3171 // Global Method Pool and Selector Serialization
3172 //===----------------------------------------------------------------------===//
3173
3174 namespace {
3175
3176 // Trait used for the on-disk hash table used in the method pool.
3177 class ASTMethodPoolTrait {
3178   ASTWriter &Writer;
3179
3180 public:
3181   using key_type = Selector;
3182   using key_type_ref = key_type;
3183
3184   struct data_type {
3185     SelectorID ID;
3186     ObjCMethodList Instance, Factory;
3187   };
3188   using data_type_ref = const data_type &;
3189
3190   using hash_value_type = unsigned;
3191   using offset_type = unsigned;
3192
3193   explicit ASTMethodPoolTrait(ASTWriter &Writer) : Writer(Writer) {}
3194
3195   static hash_value_type ComputeHash(Selector Sel) {
3196     return serialization::ComputeHash(Sel);
3197   }
3198
3199   std::pair<unsigned, unsigned>
3200     EmitKeyDataLength(raw_ostream& Out, Selector Sel,
3201                       data_type_ref Methods) {
3202     unsigned KeyLen = 2 + (Sel.getNumArgs()? Sel.getNumArgs() * 4 : 4);
3203     unsigned DataLen = 4 + 2 + 2; // 2 bytes for each of the method counts
3204     for (const ObjCMethodList *Method = &Methods.Instance; Method;
3205          Method = Method->getNext())
3206       if (ShouldWriteMethodListNode(Method))
3207         DataLen += 4;
3208     for (const ObjCMethodList *Method = &Methods.Factory; Method;
3209          Method = Method->getNext())
3210       if (ShouldWriteMethodListNode(Method))
3211         DataLen += 4;
3212     return emitULEBKeyDataLength(KeyLen, DataLen, Out);
3213   }
3214
3215   void EmitKey(raw_ostream& Out, Selector Sel, unsigned) {
3216     using namespace llvm::support;
3217
3218     endian::Writer LE(Out, little);
3219     uint64_t Start = Out.tell();
3220     assert((Start >> 32) == 0 && "Selector key offset too large");
3221     Writer.SetSelectorOffset(Sel, Start);
3222     unsigned N = Sel.getNumArgs();
3223     LE.write<uint16_t>(N);
3224     if (N == 0)
3225       N = 1;
3226     for (unsigned I = 0; I != N; ++I)
3227       LE.write<uint32_t>(
3228           Writer.getIdentifierRef(Sel.getIdentifierInfoForSlot(I)));
3229   }
3230
3231   void EmitData(raw_ostream& Out, key_type_ref,
3232                 data_type_ref Methods, unsigned DataLen) {
3233     using namespace llvm::support;
3234
3235     endian::Writer LE(Out, little);
3236     uint64_t Start = Out.tell(); (void)Start;
3237     LE.write<uint32_t>(Methods.ID);
3238     unsigned NumInstanceMethods = 0;
3239     for (const ObjCMethodList *Method = &Methods.Instance; Method;
3240          Method = Method->getNext())
3241       if (ShouldWriteMethodListNode(Method))
3242         ++NumInstanceMethods;
3243
3244     unsigned NumFactoryMethods = 0;
3245     for (const ObjCMethodList *Method = &Methods.Factory; Method;
3246          Method = Method->getNext())
3247       if (ShouldWriteMethodListNode(Method))
3248         ++NumFactoryMethods;
3249
3250     unsigned InstanceBits = Methods.Instance.getBits();
3251     assert(InstanceBits < 4);
3252     unsigned InstanceHasMoreThanOneDeclBit =
3253         Methods.Instance.hasMoreThanOneDecl();
3254     unsigned FullInstanceBits = (NumInstanceMethods << 3) |
3255                                 (InstanceHasMoreThanOneDeclBit << 2) |
3256                                 InstanceBits;
3257     unsigned FactoryBits = Methods.Factory.getBits();
3258     assert(FactoryBits < 4);
3259     unsigned FactoryHasMoreThanOneDeclBit =
3260         Methods.Factory.hasMoreThanOneDecl();
3261     unsigned FullFactoryBits = (NumFactoryMethods << 3) |
3262                                (FactoryHasMoreThanOneDeclBit << 2) |
3263                                FactoryBits;
3264     LE.write<uint16_t>(FullInstanceBits);
3265     LE.write<uint16_t>(FullFactoryBits);
3266     for (const ObjCMethodList *Method = &Methods.Instance; Method;
3267          Method = Method->getNext())
3268       if (ShouldWriteMethodListNode(Method))
3269         LE.write<uint32_t>(Writer.getDeclID(Method->getMethod()));
3270     for (const ObjCMethodList *Method = &Methods.Factory; Method;
3271          Method = Method->getNext())
3272       if (ShouldWriteMethodListNode(Method))
3273         LE.write<uint32_t>(Writer.getDeclID(Method->getMethod()));
3274
3275     assert(Out.tell() - Start == DataLen && "Data length is wrong");
3276   }
3277
3278 private:
3279   static bool ShouldWriteMethodListNode(const ObjCMethodList *Node) {
3280     return (Node->getMethod() && !Node->getMethod()->isFromASTFile());
3281   }
3282 };
3283
3284 } // namespace
3285
3286 /// Write ObjC data: selectors and the method pool.
3287 ///
3288 /// The method pool contains both instance and factory methods, stored
3289 /// in an on-disk hash table indexed by the selector. The hash table also
3290 /// contains an empty entry for every other selector known to Sema.
3291 void ASTWriter::WriteSelectors(Sema &SemaRef) {
3292   using namespace llvm;
3293
3294   // Do we have to do anything at all?
3295   if (SemaRef.MethodPool.empty() && SelectorIDs.empty())
3296     return;
3297   unsigned NumTableEntries = 0;
3298   // Create and write out the blob that contains selectors and the method pool.
3299   {
3300     llvm::OnDiskChainedHashTableGenerator<ASTMethodPoolTrait> Generator;
3301     ASTMethodPoolTrait Trait(*this);
3302
3303     // Create the on-disk hash table representation. We walk through every
3304     // selector we've seen and look it up in the method pool.
3305     SelectorOffsets.resize(NextSelectorID - FirstSelectorID);
3306     for (auto &SelectorAndID : SelectorIDs) {
3307       Selector S = SelectorAndID.first;
3308       SelectorID ID = SelectorAndID.second;
3309       Sema::GlobalMethodPool::iterator F = SemaRef.MethodPool.find(S);
3310       ASTMethodPoolTrait::data_type Data = {
3311         ID,
3312         ObjCMethodList(),
3313         ObjCMethodList()
3314       };
3315       if (F != SemaRef.MethodPool.end()) {
3316         Data.Instance = F->second.first;
3317         Data.Factory = F->second.second;
3318       }
3319       // Only write this selector if it's not in an existing AST or something
3320       // changed.
3321       if (Chain && ID < FirstSelectorID) {
3322         // Selector already exists. Did it change?
3323         bool changed = false;
3324         for (ObjCMethodList *M = &Data.Instance; M && M->getMethod();
3325              M = M->getNext()) {
3326           if (!M->getMethod()->isFromASTFile()) {
3327             changed = true;
3328             Data.Instance = *M;
3329             break;
3330           }
3331         }
3332         for (ObjCMethodList *M = &Data.Factory; M && M->getMethod();
3333              M = M->getNext()) {
3334           if (!M->getMethod()->isFromASTFile()) {
3335             changed = true;
3336             Data.Factory = *M;
3337             break;
3338           }
3339         }
3340         if (!changed)
3341           continue;
3342       } else if (Data.Instance.getMethod() || Data.Factory.getMethod()) {
3343         // A new method pool entry.
3344         ++NumTableEntries;
3345       }
3346       Generator.insert(S, Data, Trait);
3347     }
3348
3349     // Create the on-disk hash table in a buffer.
3350     SmallString<4096> MethodPool;
3351     uint32_t BucketOffset;
3352     {
3353       using namespace llvm::support;
3354
3355       ASTMethodPoolTrait Trait(*this);
3356       llvm::raw_svector_ostream Out(MethodPool);
3357       // Make sure that no bucket is at offset 0
3358       endian::write<uint32_t>(Out, 0, little);
3359       BucketOffset = Generator.Emit(Out, Trait);
3360     }
3361
3362     // Create a blob abbreviation
3363     auto Abbrev = std::make_shared<BitCodeAbbrev>();
3364     Abbrev->Add(BitCodeAbbrevOp(METHOD_POOL));
3365     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
3366     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
3367     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3368     unsigned MethodPoolAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3369
3370     // Write the method pool
3371     {
3372       RecordData::value_type Record[] = {METHOD_POOL, BucketOffset,
3373                                          NumTableEntries};
3374       Stream.EmitRecordWithBlob(MethodPoolAbbrev, Record, MethodPool);
3375     }
3376
3377     // Create a blob abbreviation for the selector table offsets.
3378     Abbrev = std::make_shared<BitCodeAbbrev>();
3379     Abbrev->Add(BitCodeAbbrevOp(SELECTOR_OFFSETS));
3380     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // size
3381     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // first ID
3382     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3383     unsigned SelectorOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3384
3385     // Write the selector offsets table.
3386     {
3387       RecordData::value_type Record[] = {
3388           SELECTOR_OFFSETS, SelectorOffsets.size(),
3389           FirstSelectorID - NUM_PREDEF_SELECTOR_IDS};
3390       Stream.EmitRecordWithBlob(SelectorOffsetAbbrev, Record,
3391                                 bytes(SelectorOffsets));
3392     }
3393   }
3394 }
3395
3396 /// Write the selectors referenced in @selector expression into AST file.
3397 void ASTWriter::WriteReferencedSelectorsPool(Sema &SemaRef) {
3398   using namespace llvm;
3399
3400   if (SemaRef.ReferencedSelectors.empty())
3401     return;
3402
3403   RecordData Record;
3404   ASTRecordWriter Writer(*this, Record);
3405
3406   // Note: this writes out all references even for a dependent AST. But it is
3407   // very tricky to fix, and given that @selector shouldn't really appear in
3408   // headers, probably not worth it. It's not a correctness issue.
3409   for (auto &SelectorAndLocation : SemaRef.ReferencedSelectors) {
3410     Selector Sel = SelectorAndLocation.first;
3411     SourceLocation Loc = SelectorAndLocation.second;
3412     Writer.AddSelectorRef(Sel);
3413     Writer.AddSourceLocation(Loc);
3414   }
3415   Writer.Emit(REFERENCED_SELECTOR_POOL);
3416 }
3417
3418 //===----------------------------------------------------------------------===//
3419 // Identifier Table Serialization
3420 //===----------------------------------------------------------------------===//
3421
3422 /// Determine the declaration that should be put into the name lookup table to
3423 /// represent the given declaration in this module. This is usually D itself,
3424 /// but if D was imported and merged into a local declaration, we want the most
3425 /// recent local declaration instead. The chosen declaration will be the most
3426 /// recent declaration in any module that imports this one.
3427 static NamedDecl *getDeclForLocalLookup(const LangOptions &LangOpts,
3428                                         NamedDecl *D) {
3429   if (!LangOpts.Modules || !D->isFromASTFile())
3430     return D;
3431
3432   if (Decl *Redecl = D->getPreviousDecl()) {
3433     // For Redeclarable decls, a prior declaration might be local.
3434     for (; Redecl; Redecl = Redecl->getPreviousDecl()) {
3435       // If we find a local decl, we're done.
3436       if (!Redecl->isFromASTFile()) {
3437         // Exception: in very rare cases (for injected-class-names), not all
3438         // redeclarations are in the same semantic context. Skip ones in a
3439         // different context. They don't go in this lookup table at all.
3440         if (!Redecl->getDeclContext()->getRedeclContext()->Equals(
3441                 D->getDeclContext()->getRedeclContext()))
3442           continue;
3443         return cast<NamedDecl>(Redecl);
3444       }
3445
3446       // If we find a decl from a (chained-)PCH stop since we won't find a
3447       // local one.
3448       if (Redecl->getOwningModuleID() == 0)
3449         break;
3450     }
3451   } else if (Decl *First = D->getCanonicalDecl()) {
3452     // For Mergeable decls, the first decl might be local.
3453     if (!First->isFromASTFile())
3454       return cast<NamedDecl>(First);
3455   }
3456
3457   // All declarations are imported. Our most recent declaration will also be
3458   // the most recent one in anyone who imports us.
3459   return D;
3460 }
3461
3462 namespace {
3463
3464 class ASTIdentifierTableTrait {
3465   ASTWriter &Writer;
3466   Preprocessor &PP;
3467   IdentifierResolver &IdResolver;
3468   bool IsModule;
3469   bool NeedDecls;
3470   ASTWriter::RecordData *InterestingIdentifierOffsets;
3471
3472   /// Determines whether this is an "interesting" identifier that needs a
3473   /// full IdentifierInfo structure written into the hash table. Notably, this
3474   /// doesn't check whether the name has macros defined; use PublicMacroIterator
3475   /// to check that.
3476   bool isInterestingIdentifier(const IdentifierInfo *II, uint64_t MacroOffset) {
3477     if (MacroOffset || II->isPoisoned() ||
3478         (!IsModule && II->getObjCOrBuiltinID()) ||
3479         II->hasRevertedTokenIDToIdentifier() ||
3480         (NeedDecls && II->getFETokenInfo()))
3481       return true;
3482
3483     return false;
3484   }
3485
3486 public:
3487   using key_type = IdentifierInfo *;
3488   using key_type_ref = key_type;
3489
3490   using data_type = IdentID;
3491   using data_type_ref = data_type;
3492
3493   using hash_value_type = unsigned;
3494   using offset_type = unsigned;
3495
3496   ASTIdentifierTableTrait(ASTWriter &Writer, Preprocessor &PP,
3497                           IdentifierResolver &IdResolver, bool IsModule,
3498                           ASTWriter::RecordData *InterestingIdentifierOffsets)
3499       : Writer(Writer), PP(PP), IdResolver(IdResolver), IsModule(IsModule),
3500         NeedDecls(!IsModule || !Writer.getLangOpts().CPlusPlus),
3501         InterestingIdentifierOffsets(InterestingIdentifierOffsets) {}
3502
3503   bool needDecls() const { return NeedDecls; }
3504
3505   static hash_value_type ComputeHash(const IdentifierInfo* II) {
3506     return llvm::djbHash(II->getName());
3507   }
3508
3509   bool isInterestingIdentifier(const IdentifierInfo *II) {
3510     auto MacroOffset = Writer.getMacroDirectivesOffset(II);
3511     return isInterestingIdentifier(II, MacroOffset);
3512   }
3513
3514   bool isInterestingNonMacroIdentifier(const IdentifierInfo *II) {
3515     return isInterestingIdentifier(II, 0);
3516   }
3517
3518   std::pair<unsigned, unsigned>
3519   EmitKeyDataLength(raw_ostream& Out, IdentifierInfo* II, IdentID ID) {
3520     // Record the location of the identifier data. This is used when generating
3521     // the mapping from persistent IDs to strings.
3522     Writer.SetIdentifierOffset(II, Out.tell());
3523
3524     // Emit the offset of the key/data length information to the interesting
3525     // identifiers table if necessary.
3526     if (InterestingIdentifierOffsets && isInterestingIdentifier(II))
3527       InterestingIdentifierOffsets->push_back(Out.tell());
3528
3529     unsigned KeyLen = II->getLength() + 1;
3530     unsigned DataLen = 4; // 4 bytes for the persistent ID << 1
3531     auto MacroOffset = Writer.getMacroDirectivesOffset(II);
3532     if (isInterestingIdentifier(II, MacroOffset)) {
3533       DataLen += 2; // 2 bytes for builtin ID
3534       DataLen += 2; // 2 bytes for flags
3535       if (MacroOffset)
3536         DataLen += 4; // MacroDirectives offset.
3537
3538       if (NeedDecls) {
3539         for (IdentifierResolver::iterator D = IdResolver.begin(II),
3540                                        DEnd = IdResolver.end();
3541              D != DEnd; ++D)
3542           DataLen += 4;
3543       }
3544     }
3545     return emitULEBKeyDataLength(KeyLen, DataLen, Out);
3546   }
3547
3548   void EmitKey(raw_ostream& Out, const IdentifierInfo* II,
3549                unsigned KeyLen) {
3550     Out.write(II->getNameStart(), KeyLen);
3551   }
3552
3553   void EmitData(raw_ostream& Out, IdentifierInfo* II,
3554                 IdentID ID, unsigned) {
3555     using namespace llvm::support;
3556
3557     endian::Writer LE(Out, little);
3558
3559     auto MacroOffset = Writer.getMacroDirectivesOffset(II);
3560     if (!isInterestingIdentifier(II, MacroOffset)) {
3561       LE.write<uint32_t>(ID << 1);
3562       return;
3563     }
3564
3565     LE.write<uint32_t>((ID << 1) | 0x01);
3566     uint32_t Bits = (uint32_t)II->getObjCOrBuiltinID();
3567     assert((Bits & 0xffff) == Bits && "ObjCOrBuiltinID too big for ASTReader.");
3568     LE.write<uint16_t>(Bits);
3569     Bits = 0;
3570     bool HadMacroDefinition = MacroOffset != 0;
3571     Bits = (Bits << 1) | unsigned(HadMacroDefinition);
3572     Bits = (Bits << 1) | unsigned(II->isExtensionToken());
3573     Bits = (Bits << 1) | unsigned(II->isPoisoned());
3574     Bits = (Bits << 1) | unsigned(II->hasRevertedTokenIDToIdentifier());
3575     Bits = (Bits << 1) | unsigned(II->isCPlusPlusOperatorKeyword());
3576     LE.write<uint16_t>(Bits);
3577
3578     if (HadMacroDefinition)
3579       LE.write<uint32_t>(MacroOffset);
3580
3581     if (NeedDecls) {
3582       // Emit the declaration IDs in reverse order, because the
3583       // IdentifierResolver provides the declarations as they would be
3584       // visible (e.g., the function "stat" would come before the struct
3585       // "stat"), but the ASTReader adds declarations to the end of the list
3586       // (so we need to see the struct "stat" before the function "stat").
3587       // Only emit declarations that aren't from a chained PCH, though.
3588       SmallVector<NamedDecl *, 16> Decls(IdResolver.begin(II),
3589                                          IdResolver.end());
3590       for (NamedDecl *D : llvm::reverse(Decls))
3591         LE.write<uint32_t>(
3592             Writer.getDeclID(getDeclForLocalLookup(PP.getLangOpts(), D)));
3593     }
3594   }
3595 };
3596
3597 } // namespace
3598
3599 /// Write the identifier table into the AST file.
3600 ///
3601 /// The identifier table consists of a blob containing string data
3602 /// (the actual identifiers themselves) and a separate "offsets" index
3603 /// that maps identifier IDs to locations within the blob.
3604 void ASTWriter::WriteIdentifierTable(Preprocessor &PP,
3605                                      IdentifierResolver &IdResolver,
3606                                      bool IsModule) {
3607   using namespace llvm;
3608
3609   RecordData InterestingIdents;
3610
3611   // Create and write out the blob that contains the identifier
3612   // strings.
3613   {
3614     llvm::OnDiskChainedHashTableGenerator<ASTIdentifierTableTrait> Generator;
3615     ASTIdentifierTableTrait Trait(
3616         *this, PP, IdResolver, IsModule,
3617         (getLangOpts().CPlusPlus && IsModule) ? &InterestingIdents : nullptr);
3618
3619     // Look for any identifiers that were named while processing the
3620     // headers, but are otherwise not needed. We add these to the hash
3621     // table to enable checking of the predefines buffer in the case
3622     // where the user adds new macro definitions when building the AST
3623     // file.
3624     SmallVector<const IdentifierInfo *, 128> IIs;
3625     for (const auto &ID : PP.getIdentifierTable())
3626       IIs.push_back(ID.second);
3627     // Sort the identifiers lexicographically before getting them references so
3628     // that their order is stable.
3629     llvm::sort(IIs, llvm::deref<std::less<>>());
3630     for (const IdentifierInfo *II : IIs)
3631       if (Trait.isInterestingNonMacroIdentifier(II))
3632         getIdentifierRef(II);
3633
3634     // Create the on-disk hash table representation. We only store offsets
3635     // for identifiers that appear here for the first time.
3636     IdentifierOffsets.resize(NextIdentID - FirstIdentID);
3637     for (auto IdentIDPair : IdentifierIDs) {
3638       auto *II = const_cast<IdentifierInfo *>(IdentIDPair.first);
3639       IdentID ID = IdentIDPair.second;
3640       assert(II && "NULL identifier in identifier table");
3641       // Write out identifiers if either the ID is local or the identifier has
3642       // changed since it was loaded.
3643       if (ID >= FirstIdentID || !Chain || !II->isFromAST()
3644           || II->hasChangedSinceDeserialization() ||
3645           (Trait.needDecls() &&
3646            II->hasFETokenInfoChangedSinceDeserialization()))
3647         Generator.insert(II, ID, Trait);
3648     }
3649
3650     // Create the on-disk hash table in a buffer.
3651     SmallString<4096> IdentifierTable;
3652     uint32_t BucketOffset;
3653     {
3654       using namespace llvm::support;
3655
3656       llvm::raw_svector_ostream Out(IdentifierTable);
3657       // Make sure that no bucket is at offset 0
3658       endian::write<uint32_t>(Out, 0, little);
3659       BucketOffset = Generator.Emit(Out, Trait);
3660     }
3661
3662     // Create a blob abbreviation
3663     auto Abbrev = std::make_shared<BitCodeAbbrev>();
3664     Abbrev->Add(BitCodeAbbrevOp(IDENTIFIER_TABLE));
3665     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
3666     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3667     unsigned IDTableAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3668
3669     // Write the identifier table
3670     RecordData::value_type Record[] = {IDENTIFIER_TABLE, BucketOffset};
3671     Stream.EmitRecordWithBlob(IDTableAbbrev, Record, IdentifierTable);
3672   }
3673
3674   // Write the offsets table for identifier IDs.
3675   auto Abbrev = std::make_shared<BitCodeAbbrev>();
3676   Abbrev->Add(BitCodeAbbrevOp(IDENTIFIER_OFFSET));
3677   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // # of identifiers
3678   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // first ID
3679   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3680   unsigned IdentifierOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3681
3682 #ifndef NDEBUG
3683   for (unsigned I = 0, N = IdentifierOffsets.size(); I != N; ++I)
3684     assert(IdentifierOffsets[I] && "Missing identifier offset?");
3685 #endif
3686
3687   RecordData::value_type Record[] = {IDENTIFIER_OFFSET,
3688                                      IdentifierOffsets.size(),
3689                                      FirstIdentID - NUM_PREDEF_IDENT_IDS};
3690   Stream.EmitRecordWithBlob(IdentifierOffsetAbbrev, Record,
3691                             bytes(IdentifierOffsets));
3692
3693   // In C++, write the list of interesting identifiers (those that are
3694   // defined as macros, poisoned, or similar unusual things).
3695   if (!InterestingIdents.empty())
3696     Stream.EmitRecord(INTERESTING_IDENTIFIERS, InterestingIdents);
3697 }
3698
3699 //===----------------------------------------------------------------------===//
3700 // DeclContext's Name Lookup Table Serialization
3701 //===----------------------------------------------------------------------===//
3702
3703 namespace {
3704
3705 // Trait used for the on-disk hash table used in the method pool.
3706 class ASTDeclContextNameLookupTrait {
3707   ASTWriter &Writer;
3708   llvm::SmallVector<DeclID, 64> DeclIDs;
3709
3710 public:
3711   using key_type = DeclarationNameKey;
3712   using key_type_ref = key_type;
3713
3714   /// A start and end index into DeclIDs, representing a sequence of decls.
3715   using data_type = std::pair<unsigned, unsigned>;
3716   using data_type_ref = const data_type &;
3717
3718   using hash_value_type = unsigned;
3719   using offset_type = unsigned;
3720
3721   explicit ASTDeclContextNameLookupTrait(ASTWriter &Writer) : Writer(Writer) {}
3722
3723   template<typename Coll>
3724   data_type getData(const Coll &Decls) {
3725     unsigned Start = DeclIDs.size();
3726     for (NamedDecl *D : Decls) {
3727       DeclIDs.push_back(
3728           Writer.GetDeclRef(getDeclForLocalLookup(Writer.getLangOpts(), D)));
3729     }
3730     return std::make_pair(Start, DeclIDs.size());
3731   }
3732
3733   data_type ImportData(const reader::ASTDeclContextNameLookupTrait::data_type &FromReader) {
3734     unsigned Start = DeclIDs.size();
3735     llvm::append_range(DeclIDs, FromReader);
3736     return std::make_pair(Start, DeclIDs.size());
3737   }
3738
3739   static bool EqualKey(key_type_ref a, key_type_ref b) {
3740     return a == b;
3741   }
3742
3743   hash_value_type ComputeHash(DeclarationNameKey Name) {
3744     return Name.getHash();
3745   }
3746
3747   void EmitFileRef(raw_ostream &Out, ModuleFile *F) const {
3748     assert(Writer.hasChain() &&
3749            "have reference to loaded module file but no chain?");
3750
3751     using namespace llvm::support;
3752
3753     endian::write<uint32_t>(Out, Writer.getChain()->getModuleFileID(F), little);
3754   }
3755
3756   std::pair<unsigned, unsigned> EmitKeyDataLength(raw_ostream &Out,
3757                                                   DeclarationNameKey Name,
3758                                                   data_type_ref Lookup) {
3759     unsigned KeyLen = 1;
3760     switch (Name.getKind()) {
3761     case DeclarationName::Identifier:
3762     case DeclarationName::ObjCZeroArgSelector:
3763     case DeclarationName::ObjCOneArgSelector:
3764     case DeclarationName::ObjCMultiArgSelector:
3765     case DeclarationName::CXXLiteralOperatorName:
3766     case DeclarationName::CXXDeductionGuideName:
3767       KeyLen += 4;
3768       break;
3769     case DeclarationName::CXXOperatorName:
3770       KeyLen += 1;
3771       break;
3772     case DeclarationName::CXXConstructorName:
3773     case DeclarationName::CXXDestructorName:
3774     case DeclarationName::CXXConversionFunctionName:
3775     case DeclarationName::CXXUsingDirective:
3776       break;
3777     }
3778
3779     // 4 bytes for each DeclID.
3780     unsigned DataLen = 4 * (Lookup.second - Lookup.first);
3781
3782     return emitULEBKeyDataLength(KeyLen, DataLen, Out);
3783   }
3784
3785   void EmitKey(raw_ostream &Out, DeclarationNameKey Name, unsigned) {
3786     using namespace llvm::support;
3787
3788     endian::Writer LE(Out, little);
3789     LE.write<uint8_t>(Name.getKind());
3790     switch (Name.getKind()) {
3791     case DeclarationName::Identifier:
3792     case DeclarationName::CXXLiteralOperatorName:
3793     case DeclarationName::CXXDeductionGuideName:
3794       LE.write<uint32_t>(Writer.getIdentifierRef(Name.getIdentifier()));
3795       return;
3796     case DeclarationName::ObjCZeroArgSelector:
3797     case DeclarationName::ObjCOneArgSelector:
3798     case DeclarationName::ObjCMultiArgSelector:
3799       LE.write<uint32_t>(Writer.getSelectorRef(Name.getSelector()));
3800       return;
3801     case DeclarationName::CXXOperatorName:
3802       assert(Name.getOperatorKind() < NUM_OVERLOADED_OPERATORS &&
3803              "Invalid operator?");
3804       LE.write<uint8_t>(Name.getOperatorKind());
3805       return;
3806     case DeclarationName::CXXConstructorName:
3807     case DeclarationName::CXXDestructorName:
3808     case DeclarationName::CXXConversionFunctionName:
3809     case DeclarationName::CXXUsingDirective:
3810       return;
3811     }
3812
3813     llvm_unreachable("Invalid name kind?");
3814   }
3815
3816   void EmitData(raw_ostream &Out, key_type_ref, data_type Lookup,
3817                 unsigned DataLen) {
3818     using namespace llvm::support;
3819
3820     endian::Writer LE(Out, little);
3821     uint64_t Start = Out.tell(); (void)Start;
3822     for (unsigned I = Lookup.first, N = Lookup.second; I != N; ++I)
3823       LE.write<uint32_t>(DeclIDs[I]);
3824     assert(Out.tell() - Start == DataLen && "Data length is wrong");
3825   }
3826 };
3827
3828 } // namespace
3829
3830 bool ASTWriter::isLookupResultExternal(StoredDeclsList &Result,
3831                                        DeclContext *DC) {
3832   return Result.hasExternalDecls() &&
3833          DC->hasNeedToReconcileExternalVisibleStorage();
3834 }
3835
3836 bool ASTWriter::isLookupResultEntirelyExternal(StoredDeclsList &Result,
3837                                                DeclContext *DC) {
3838   for (auto *D : Result.getLookupResult())
3839     if (!getDeclForLocalLookup(getLangOpts(), D)->isFromASTFile())
3840       return false;
3841
3842   return true;
3843 }
3844
3845 void
3846 ASTWriter::GenerateNameLookupTable(const DeclContext *ConstDC,
3847                                    llvm::SmallVectorImpl<char> &LookupTable) {
3848   assert(!ConstDC->hasLazyLocalLexicalLookups() &&
3849          !ConstDC->hasLazyExternalLexicalLookups() &&
3850          "must call buildLookups first");
3851
3852   // FIXME: We need to build the lookups table, which is logically const.
3853   auto *DC = const_cast<DeclContext*>(ConstDC);
3854   assert(DC == DC->getPrimaryContext() && "only primary DC has lookup table");
3855
3856   // Create the on-disk hash table representation.
3857   MultiOnDiskHashTableGenerator<reader::ASTDeclContextNameLookupTrait,
3858                                 ASTDeclContextNameLookupTrait> Generator;
3859   ASTDeclContextNameLookupTrait Trait(*this);
3860
3861   // The first step is to collect the declaration names which we need to
3862   // serialize into the name lookup table, and to collect them in a stable
3863   // order.
3864   SmallVector<DeclarationName, 16> Names;
3865
3866   // We also build up small sets of the constructor and conversion function
3867   // names which are visible.
3868   llvm::SmallPtrSet<DeclarationName, 8> ConstructorNameSet, ConversionNameSet;
3869
3870   for (auto &Lookup : *DC->buildLookup()) {
3871     auto &Name = Lookup.first;
3872     auto &Result = Lookup.second;
3873
3874     // If there are no local declarations in our lookup result, we
3875     // don't need to write an entry for the name at all. If we can't
3876     // write out a lookup set without performing more deserialization,
3877     // just skip this entry.
3878     if (isLookupResultExternal(Result, DC) &&
3879         isLookupResultEntirelyExternal(Result, DC))
3880       continue;
3881
3882     // We also skip empty results. If any of the results could be external and
3883     // the currently available results are empty, then all of the results are
3884     // external and we skip it above. So the only way we get here with an empty
3885     // results is when no results could have been external *and* we have
3886     // external results.
3887     //
3888     // FIXME: While we might want to start emitting on-disk entries for negative
3889     // lookups into a decl context as an optimization, today we *have* to skip
3890     // them because there are names with empty lookup results in decl contexts
3891     // which we can't emit in any stable ordering: we lookup constructors and
3892     // conversion functions in the enclosing namespace scope creating empty
3893     // results for them. This in almost certainly a bug in Clang's name lookup,
3894     // but that is likely to be hard or impossible to fix and so we tolerate it
3895     // here by omitting lookups with empty results.
3896     if (Lookup.second.getLookupResult().empty())
3897       continue;
3898
3899     switch (Lookup.first.getNameKind()) {
3900     default:
3901       Names.push_back(Lookup.first);
3902       break;
3903
3904     case DeclarationName::CXXConstructorName:
3905       assert(isa<CXXRecordDecl>(DC) &&
3906              "Cannot have a constructor name outside of a class!");
3907       ConstructorNameSet.insert(Name);
3908       break;
3909
3910     case DeclarationName::CXXConversionFunctionName:
3911       assert(isa<CXXRecordDecl>(DC) &&
3912              "Cannot have a conversion function name outside of a class!");
3913       ConversionNameSet.insert(Name);
3914       break;
3915     }
3916   }
3917
3918   // Sort the names into a stable order.
3919   llvm::sort(Names);
3920
3921   if (auto *D = dyn_cast<CXXRecordDecl>(DC)) {
3922     // We need to establish an ordering of constructor and conversion function
3923     // names, and they don't have an intrinsic ordering.
3924
3925     // First we try the easy case by forming the current context's constructor
3926     // name and adding that name first. This is a very useful optimization to
3927     // avoid walking the lexical declarations in many cases, and it also
3928     // handles the only case where a constructor name can come from some other
3929     // lexical context -- when that name is an implicit constructor merged from
3930     // another declaration in the redecl chain. Any non-implicit constructor or
3931     // conversion function which doesn't occur in all the lexical contexts
3932     // would be an ODR violation.
3933     auto ImplicitCtorName = Context->DeclarationNames.getCXXConstructorName(
3934         Context->getCanonicalType(Context->getRecordType(D)));
3935     if (ConstructorNameSet.erase(ImplicitCtorName))
3936       Names.push_back(ImplicitCtorName);
3937
3938     // If we still have constructors or conversion functions, we walk all the
3939     // names in the decl and add the constructors and conversion functions
3940     // which are visible in the order they lexically occur within the context.
3941     if (!ConstructorNameSet.empty() || !ConversionNameSet.empty())
3942       for (Decl *ChildD : cast<CXXRecordDecl>(DC)->decls())
3943         if (auto *ChildND = dyn_cast<NamedDecl>(ChildD)) {
3944           auto Name = ChildND->getDeclName();
3945           switch (Name.getNameKind()) {
3946           default:
3947             continue;
3948
3949           case DeclarationName::CXXConstructorName:
3950             if (ConstructorNameSet.erase(Name))
3951               Names.push_back(Name);
3952             break;
3953
3954           case DeclarationName::CXXConversionFunctionName:
3955             if (ConversionNameSet.erase(Name))
3956               Names.push_back(Name);
3957             break;
3958           }
3959
3960           if (ConstructorNameSet.empty() && ConversionNameSet.empty())
3961             break;
3962         }
3963
3964     assert(ConstructorNameSet.empty() && "Failed to find all of the visible "
3965                                          "constructors by walking all the "
3966                                          "lexical members of the context.");
3967     assert(ConversionNameSet.empty() && "Failed to find all of the visible "
3968                                         "conversion functions by walking all "
3969                                         "the lexical members of the context.");
3970   }
3971
3972   // Next we need to do a lookup with each name into this decl context to fully
3973   // populate any results from external sources. We don't actually use the
3974   // results of these lookups because we only want to use the results after all
3975   // results have been loaded and the pointers into them will be stable.
3976   for (auto &Name : Names)
3977     DC->lookup(Name);
3978
3979   // Now we need to insert the results for each name into the hash table. For
3980   // constructor names and conversion function names, we actually need to merge
3981   // all of the results for them into one list of results each and insert
3982   // those.
3983   SmallVector<NamedDecl *, 8> ConstructorDecls;
3984   SmallVector<NamedDecl *, 8> ConversionDecls;
3985
3986   // Now loop over the names, either inserting them or appending for the two
3987   // special cases.
3988   for (auto &Name : Names) {
3989     DeclContext::lookup_result Result = DC->noload_lookup(Name);
3990
3991     switch (Name.getNameKind()) {
3992     default:
3993       Generator.insert(Name, Trait.getData(Result), Trait);
3994       break;
3995
3996     case DeclarationName::CXXConstructorName:
3997       ConstructorDecls.append(Result.begin(), Result.end());
3998       break;
3999
4000     case DeclarationName::CXXConversionFunctionName:
4001       ConversionDecls.append(Result.begin(), Result.end());
4002       break;
4003     }
4004   }
4005
4006   // Handle our two special cases if we ended up having any. We arbitrarily use
4007   // the first declaration's name here because the name itself isn't part of
4008   // the key, only the kind of name is used.
4009   if (!ConstructorDecls.empty())
4010     Generator.insert(ConstructorDecls.front()->getDeclName(),
4011                      Trait.getData(ConstructorDecls), Trait);
4012   if (!ConversionDecls.empty())
4013     Generator.insert(ConversionDecls.front()->getDeclName(),
4014                      Trait.getData(ConversionDecls), Trait);
4015
4016   // Create the on-disk hash table. Also emit the existing imported and
4017   // merged table if there is one.
4018   auto *Lookups = Chain ? Chain->getLoadedLookupTables(DC) : nullptr;
4019   Generator.emit(LookupTable, Trait, Lookups ? &Lookups->Table : nullptr);
4020 }
4021
4022 /// Write the block containing all of the declaration IDs
4023 /// visible from the given DeclContext.
4024 ///
4025 /// \returns the offset of the DECL_CONTEXT_VISIBLE block within the
4026 /// bitstream, or 0 if no block was written.
4027 uint64_t ASTWriter::WriteDeclContextVisibleBlock(ASTContext &Context,
4028                                                  DeclContext *DC) {
4029   // If we imported a key declaration of this namespace, write the visible
4030   // lookup results as an update record for it rather than including them
4031   // on this declaration. We will only look at key declarations on reload.
4032   if (isa<NamespaceDecl>(DC) && Chain &&
4033       Chain->getKeyDeclaration(cast<Decl>(DC))->isFromASTFile()) {
4034     // Only do this once, for the first local declaration of the namespace.
4035     for (auto *Prev = cast<NamespaceDecl>(DC)->getPreviousDecl(); Prev;
4036          Prev = Prev->getPreviousDecl())
4037       if (!Prev->isFromASTFile())
4038         return 0;
4039
4040     // Note that we need to emit an update record for the primary context.
4041     UpdatedDeclContexts.insert(DC->getPrimaryContext());
4042
4043     // Make sure all visible decls are written. They will be recorded later. We
4044     // do this using a side data structure so we can sort the names into
4045     // a deterministic order.
4046     StoredDeclsMap *Map = DC->getPrimaryContext()->buildLookup();
4047     SmallVector<std::pair<DeclarationName, DeclContext::lookup_result>, 16>
4048         LookupResults;
4049     if (Map) {
4050       LookupResults.reserve(Map->size());
4051       for (auto &Entry : *Map)
4052         LookupResults.push_back(
4053             std::make_pair(Entry.first, Entry.second.getLookupResult()));
4054     }
4055
4056     llvm::sort(LookupResults, llvm::less_first());
4057     for (auto &NameAndResult : LookupResults) {
4058       DeclarationName Name = NameAndResult.first;
4059       DeclContext::lookup_result Result = NameAndResult.second;
4060       if (Name.getNameKind() == DeclarationName::CXXConstructorName ||
4061           Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
4062         // We have to work around a name lookup bug here where negative lookup
4063         // results for these names get cached in namespace lookup tables (these
4064         // names should never be looked up in a namespace).
4065         assert(Result.empty() && "Cannot have a constructor or conversion "
4066                                  "function name in a namespace!");
4067         continue;
4068       }
4069
4070       for (NamedDecl *ND : Result)
4071         if (!ND->isFromASTFile())
4072           GetDeclRef(ND);
4073     }
4074
4075     return 0;
4076   }
4077
4078   if (DC->getPrimaryContext() != DC)
4079     return 0;
4080
4081   // Skip contexts which don't support name lookup.
4082   if (!DC->isLookupContext())
4083     return 0;
4084
4085   // If not in C++, we perform name lookup for the translation unit via the
4086   // IdentifierInfo chains, don't bother to build a visible-declarations table.
4087   if (DC->isTranslationUnit() && !Context.getLangOpts().CPlusPlus)
4088     return 0;
4089
4090   // Serialize the contents of the mapping used for lookup. Note that,
4091   // although we have two very different code paths, the serialized
4092   // representation is the same for both cases: a declaration name,
4093   // followed by a size, followed by references to the visible
4094   // declarations that have that name.
4095   uint64_t Offset = Stream.GetCurrentBitNo();
4096   StoredDeclsMap *Map = DC->buildLookup();
4097   if (!Map || Map->empty())
4098     return 0;
4099
4100   // Create the on-disk hash table in a buffer.
4101   SmallString<4096> LookupTable;
4102   GenerateNameLookupTable(DC, LookupTable);
4103
4104   // Write the lookup table
4105   RecordData::value_type Record[] = {DECL_CONTEXT_VISIBLE};
4106   Stream.EmitRecordWithBlob(DeclContextVisibleLookupAbbrev, Record,
4107                             LookupTable);
4108   ++NumVisibleDeclContexts;
4109   return Offset;
4110 }
4111
4112 /// Write an UPDATE_VISIBLE block for the given context.
4113 ///
4114 /// UPDATE_VISIBLE blocks contain the declarations that are added to an existing
4115 /// DeclContext in a dependent AST file. As such, they only exist for the TU
4116 /// (in C++), for namespaces, and for classes with forward-declared unscoped
4117 /// enumeration members (in C++11).
4118 void ASTWriter::WriteDeclContextVisibleUpdate(const DeclContext *DC) {
4119   StoredDeclsMap *Map = DC->getLookupPtr();
4120   if (!Map || Map->empty())
4121     return;
4122
4123   // Create the on-disk hash table in a buffer.
4124   SmallString<4096> LookupTable;
4125   GenerateNameLookupTable(DC, LookupTable);
4126
4127   // If we're updating a namespace, select a key declaration as the key for the
4128   // update record; those are the only ones that will be checked on reload.
4129   if (isa<NamespaceDecl>(DC))
4130     DC = cast<DeclContext>(Chain->getKeyDeclaration(cast<Decl>(DC)));
4131
4132   // Write the lookup table
4133   RecordData::value_type Record[] = {UPDATE_VISIBLE, getDeclID(cast<Decl>(DC))};
4134   Stream.EmitRecordWithBlob(UpdateVisibleAbbrev, Record, LookupTable);
4135 }
4136
4137 /// Write an FP_PRAGMA_OPTIONS block for the given FPOptions.
4138 void ASTWriter::WriteFPPragmaOptions(const FPOptionsOverride &Opts) {
4139   RecordData::value_type Record[] = {Opts.getAsOpaqueInt()};
4140   Stream.EmitRecord(FP_PRAGMA_OPTIONS, Record);
4141 }
4142
4143 /// Write an OPENCL_EXTENSIONS block for the given OpenCLOptions.
4144 void ASTWriter::WriteOpenCLExtensions(Sema &SemaRef) {
4145   if (!SemaRef.Context.getLangOpts().OpenCL)
4146     return;
4147
4148   const OpenCLOptions &Opts = SemaRef.getOpenCLOptions();
4149   RecordData Record;
4150   for (const auto &I:Opts.OptMap) {
4151     AddString(I.getKey(), Record);
4152     auto V = I.getValue();
4153     Record.push_back(V.Supported ? 1 : 0);
4154     Record.push_back(V.Enabled ? 1 : 0);
4155     Record.push_back(V.WithPragma ? 1 : 0);
4156     Record.push_back(V.Avail);
4157     Record.push_back(V.Core);
4158     Record.push_back(V.Opt);
4159   }
4160   Stream.EmitRecord(OPENCL_EXTENSIONS, Record);
4161 }
4162 void ASTWriter::WriteCUDAPragmas(Sema &SemaRef) {
4163   if (SemaRef.ForceCUDAHostDeviceDepth > 0) {
4164     RecordData::value_type Record[] = {SemaRef.ForceCUDAHostDeviceDepth};
4165     Stream.EmitRecord(CUDA_PRAGMA_FORCE_HOST_DEVICE_DEPTH, Record);
4166   }
4167 }
4168
4169 void ASTWriter::WriteObjCCategories() {
4170   SmallVector<ObjCCategoriesInfo, 2> CategoriesMap;
4171   RecordData Categories;
4172
4173   for (unsigned I = 0, N = ObjCClassesWithCategories.size(); I != N; ++I) {
4174     unsigned Size = 0;
4175     unsigned StartIndex = Categories.size();
4176
4177     ObjCInterfaceDecl *Class = ObjCClassesWithCategories[I];
4178
4179     // Allocate space for the size.
4180     Categories.push_back(0);
4181
4182     // Add the categories.
4183     for (ObjCInterfaceDecl::known_categories_iterator
4184            Cat = Class->known_categories_begin(),
4185            CatEnd = Class->known_categories_end();
4186          Cat != CatEnd; ++Cat, ++Size) {
4187       assert(getDeclID(*Cat) != 0 && "Bogus category");
4188       AddDeclRef(*Cat, Categories);
4189     }
4190
4191     // Update the size.
4192     Categories[StartIndex] = Size;
4193
4194     // Record this interface -> category map.
4195     ObjCCategoriesInfo CatInfo = { getDeclID(Class), StartIndex };
4196     CategoriesMap.push_back(CatInfo);
4197   }
4198
4199   // Sort the categories map by the definition ID, since the reader will be
4200   // performing binary searches on this information.
4201   llvm::array_pod_sort(CategoriesMap.begin(), CategoriesMap.end());
4202
4203   // Emit the categories map.
4204   using namespace llvm;
4205
4206   auto Abbrev = std::make_shared<BitCodeAbbrev>();
4207   Abbrev->Add(BitCodeAbbrevOp(OBJC_CATEGORIES_MAP));
4208   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // # of entries
4209   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
4210   unsigned AbbrevID = Stream.EmitAbbrev(std::move(Abbrev));
4211
4212   RecordData::value_type Record[] = {OBJC_CATEGORIES_MAP, CategoriesMap.size()};
4213   Stream.EmitRecordWithBlob(AbbrevID, Record,
4214                             reinterpret_cast<char *>(CategoriesMap.data()),
4215                             CategoriesMap.size() * sizeof(ObjCCategoriesInfo));
4216
4217   // Emit the category lists.
4218   Stream.EmitRecord(OBJC_CATEGORIES, Categories);
4219 }
4220
4221 void ASTWriter::WriteLateParsedTemplates(Sema &SemaRef) {
4222   Sema::LateParsedTemplateMapT &LPTMap = SemaRef.LateParsedTemplateMap;
4223
4224   if (LPTMap.empty())
4225     return;
4226
4227   RecordData Record;
4228   for (auto &LPTMapEntry : LPTMap) {
4229     const FunctionDecl *FD = LPTMapEntry.first;
4230     LateParsedTemplate &LPT = *LPTMapEntry.second;
4231     AddDeclRef(FD, Record);
4232     AddDeclRef(LPT.D, Record);
4233     Record.push_back(LPT.Toks.size());
4234
4235     for (const auto &Tok : LPT.Toks) {
4236       AddToken(Tok, Record);
4237     }
4238   }
4239   Stream.EmitRecord(LATE_PARSED_TEMPLATE, Record);
4240 }
4241
4242 /// Write the state of 'pragma clang optimize' at the end of the module.
4243 void ASTWriter::WriteOptimizePragmaOptions(Sema &SemaRef) {
4244   RecordData Record;
4245   SourceLocation PragmaLoc = SemaRef.getOptimizeOffPragmaLocation();
4246   AddSourceLocation(PragmaLoc, Record);
4247   Stream.EmitRecord(OPTIMIZE_PRAGMA_OPTIONS, Record);
4248 }
4249
4250 /// Write the state of 'pragma ms_struct' at the end of the module.
4251 void ASTWriter::WriteMSStructPragmaOptions(Sema &SemaRef) {
4252   RecordData Record;
4253   Record.push_back(SemaRef.MSStructPragmaOn ? PMSST_ON : PMSST_OFF);
4254   Stream.EmitRecord(MSSTRUCT_PRAGMA_OPTIONS, Record);
4255 }
4256
4257 /// Write the state of 'pragma pointers_to_members' at the end of the
4258 //module.
4259 void ASTWriter::WriteMSPointersToMembersPragmaOptions(Sema &SemaRef) {
4260   RecordData Record;
4261   Record.push_back(SemaRef.MSPointerToMemberRepresentationMethod);
4262   AddSourceLocation(SemaRef.ImplicitMSInheritanceAttrLoc, Record);
4263   Stream.EmitRecord(POINTERS_TO_MEMBERS_PRAGMA_OPTIONS, Record);
4264 }
4265
4266 /// Write the state of 'pragma align/pack' at the end of the module.
4267 void ASTWriter::WritePackPragmaOptions(Sema &SemaRef) {
4268   // Don't serialize pragma align/pack state for modules, since it should only
4269   // take effect on a per-submodule basis.
4270   if (WritingModule)
4271     return;
4272
4273   RecordData Record;
4274   AddAlignPackInfo(SemaRef.AlignPackStack.CurrentValue, Record);
4275   AddSourceLocation(SemaRef.AlignPackStack.CurrentPragmaLocation, Record);
4276   Record.push_back(SemaRef.AlignPackStack.Stack.size());
4277   for (const auto &StackEntry : SemaRef.AlignPackStack.Stack) {
4278     AddAlignPackInfo(StackEntry.Value, Record);
4279     AddSourceLocation(StackEntry.PragmaLocation, Record);
4280     AddSourceLocation(StackEntry.PragmaPushLocation, Record);
4281     AddString(StackEntry.StackSlotLabel, Record);
4282   }
4283   Stream.EmitRecord(ALIGN_PACK_PRAGMA_OPTIONS, Record);
4284 }
4285
4286 /// Write the state of 'pragma float_control' at the end of the module.
4287 void ASTWriter::WriteFloatControlPragmaOptions(Sema &SemaRef) {
4288   // Don't serialize pragma float_control state for modules,
4289   // since it should only take effect on a per-submodule basis.
4290   if (WritingModule)
4291     return;
4292
4293   RecordData Record;
4294   Record.push_back(SemaRef.FpPragmaStack.CurrentValue.getAsOpaqueInt());
4295   AddSourceLocation(SemaRef.FpPragmaStack.CurrentPragmaLocation, Record);
4296   Record.push_back(SemaRef.FpPragmaStack.Stack.size());
4297   for (const auto &StackEntry : SemaRef.FpPragmaStack.Stack) {
4298     Record.push_back(StackEntry.Value.getAsOpaqueInt());
4299     AddSourceLocation(StackEntry.PragmaLocation, Record);
4300     AddSourceLocation(StackEntry.PragmaPushLocation, Record);
4301     AddString(StackEntry.StackSlotLabel, Record);
4302   }
4303   Stream.EmitRecord(FLOAT_CONTROL_PRAGMA_OPTIONS, Record);
4304 }
4305
4306 void ASTWriter::WriteModuleFileExtension(Sema &SemaRef,
4307                                          ModuleFileExtensionWriter &Writer) {
4308   // Enter the extension block.
4309   Stream.EnterSubblock(EXTENSION_BLOCK_ID, 4);
4310
4311   // Emit the metadata record abbreviation.
4312   auto Abv = std::make_shared<llvm::BitCodeAbbrev>();
4313   Abv->Add(llvm::BitCodeAbbrevOp(EXTENSION_METADATA));
4314   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4315   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4316   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4317   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4318   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Blob));
4319   unsigned Abbrev = Stream.EmitAbbrev(std::move(Abv));
4320
4321   // Emit the metadata record.
4322   RecordData Record;
4323   auto Metadata = Writer.getExtension()->getExtensionMetadata();
4324   Record.push_back(EXTENSION_METADATA);
4325   Record.push_back(Metadata.MajorVersion);
4326   Record.push_back(Metadata.MinorVersion);
4327   Record.push_back(Metadata.BlockName.size());
4328   Record.push_back(Metadata.UserInfo.size());
4329   SmallString<64> Buffer;
4330   Buffer += Metadata.BlockName;
4331   Buffer += Metadata.UserInfo;
4332   Stream.EmitRecordWithBlob(Abbrev, Record, Buffer);
4333
4334   // Emit the contents of the extension block.
4335   Writer.writeExtensionContents(SemaRef, Stream);
4336
4337   // Exit the extension block.
4338   Stream.ExitBlock();
4339 }
4340
4341 //===----------------------------------------------------------------------===//
4342 // General Serialization Routines
4343 //===----------------------------------------------------------------------===//
4344
4345 void ASTRecordWriter::AddAttr(const Attr *A) {
4346   auto &Record = *this;
4347   // FIXME: Clang can't handle the serialization/deserialization of
4348   // preferred_name properly now. See
4349   // https://github.com/llvm/llvm-project/issues/56490 for example.
4350   if (!A || (isa<PreferredNameAttr>(A) && Writer->isWritingNamedModules()))
4351     return Record.push_back(0);
4352
4353   Record.push_back(A->getKind() + 1); // FIXME: stable encoding, target attrs
4354
4355   Record.AddIdentifierRef(A->getAttrName());
4356   Record.AddIdentifierRef(A->getScopeName());
4357   Record.AddSourceRange(A->getRange());
4358   Record.AddSourceLocation(A->getScopeLoc());
4359   Record.push_back(A->getParsedKind());
4360   Record.push_back(A->getSyntax());
4361   Record.push_back(A->getAttributeSpellingListIndexRaw());
4362
4363 #include "clang/Serialization/AttrPCHWrite.inc"
4364 }
4365
4366 /// Emit the list of attributes to the specified record.
4367 void ASTRecordWriter::AddAttributes(ArrayRef<const Attr *> Attrs) {
4368   push_back(Attrs.size());
4369   for (const auto *A : Attrs)
4370     AddAttr(A);
4371 }
4372
4373 void ASTWriter::AddToken(const Token &Tok, RecordDataImpl &Record) {
4374   AddSourceLocation(Tok.getLocation(), Record);
4375   Record.push_back(Tok.getLength());
4376
4377   // FIXME: When reading literal tokens, reconstruct the literal pointer
4378   // if it is needed.
4379   AddIdentifierRef(Tok.getIdentifierInfo(), Record);
4380   // FIXME: Should translate token kind to a stable encoding.
4381   Record.push_back(Tok.getKind());
4382   // FIXME: Should translate token flags to a stable encoding.
4383   Record.push_back(Tok.getFlags());
4384 }
4385
4386 void ASTWriter::AddString(StringRef Str, RecordDataImpl &Record) {
4387   Record.push_back(Str.size());
4388   Record.insert(Record.end(), Str.begin(), Str.end());
4389 }
4390
4391 bool ASTWriter::PreparePathForOutput(SmallVectorImpl<char> &Path) {
4392   assert(Context && "should have context when outputting path");
4393
4394   bool Changed =
4395       cleanPathForOutput(Context->getSourceManager().getFileManager(), Path);
4396
4397   // Remove a prefix to make the path relative, if relevant.
4398   const char *PathBegin = Path.data();
4399   const char *PathPtr =
4400       adjustFilenameForRelocatableAST(PathBegin, BaseDirectory);
4401   if (PathPtr != PathBegin) {
4402     Path.erase(Path.begin(), Path.begin() + (PathPtr - PathBegin));
4403     Changed = true;
4404   }
4405
4406   return Changed;
4407 }
4408
4409 void ASTWriter::AddPath(StringRef Path, RecordDataImpl &Record) {
4410   SmallString<128> FilePath(Path);
4411   PreparePathForOutput(FilePath);
4412   AddString(FilePath, Record);
4413 }
4414
4415 void ASTWriter::EmitRecordWithPath(unsigned Abbrev, RecordDataRef Record,
4416                                    StringRef Path) {
4417   SmallString<128> FilePath(Path);
4418   PreparePathForOutput(FilePath);
4419   Stream.EmitRecordWithBlob(Abbrev, Record, FilePath);
4420 }
4421
4422 void ASTWriter::AddVersionTuple(const VersionTuple &Version,
4423                                 RecordDataImpl &Record) {
4424   Record.push_back(Version.getMajor());
4425   if (Optional<unsigned> Minor = Version.getMinor())
4426     Record.push_back(*Minor + 1);
4427   else
4428     Record.push_back(0);
4429   if (Optional<unsigned> Subminor = Version.getSubminor())
4430     Record.push_back(*Subminor + 1);
4431   else
4432     Record.push_back(0);
4433 }
4434
4435 /// Note that the identifier II occurs at the given offset
4436 /// within the identifier table.
4437 void ASTWriter::SetIdentifierOffset(const IdentifierInfo *II, uint32_t Offset) {
4438   IdentID ID = IdentifierIDs[II];
4439   // Only store offsets new to this AST file. Other identifier names are looked
4440   // up earlier in the chain and thus don't need an offset.
4441   if (ID >= FirstIdentID)
4442     IdentifierOffsets[ID - FirstIdentID] = Offset;
4443 }
4444
4445 /// Note that the selector Sel occurs at the given offset
4446 /// within the method pool/selector table.
4447 void ASTWriter::SetSelectorOffset(Selector Sel, uint32_t Offset) {
4448   unsigned ID = SelectorIDs[Sel];
4449   assert(ID && "Unknown selector");
4450   // Don't record offsets for selectors that are also available in a different
4451   // file.
4452   if (ID < FirstSelectorID)
4453     return;
4454   SelectorOffsets[ID - FirstSelectorID] = Offset;
4455 }
4456
4457 ASTWriter::ASTWriter(llvm::BitstreamWriter &Stream,
4458                      SmallVectorImpl<char> &Buffer,
4459                      InMemoryModuleCache &ModuleCache,
4460                      ArrayRef<std::shared_ptr<ModuleFileExtension>> Extensions,
4461                      bool IncludeTimestamps)
4462     : Stream(Stream), Buffer(Buffer), ModuleCache(ModuleCache),
4463       IncludeTimestamps(IncludeTimestamps) {
4464   for (const auto &Ext : Extensions) {
4465     if (auto Writer = Ext->createExtensionWriter(*this))
4466       ModuleFileExtensionWriters.push_back(std::move(Writer));
4467   }
4468 }
4469
4470 ASTWriter::~ASTWriter() = default;
4471
4472 const LangOptions &ASTWriter::getLangOpts() const {
4473   assert(WritingAST && "can't determine lang opts when not writing AST");
4474   return Context->getLangOpts();
4475 }
4476
4477 time_t ASTWriter::getTimestampForOutput(const FileEntry *E) const {
4478   return IncludeTimestamps ? E->getModificationTime() : 0;
4479 }
4480
4481 ASTFileSignature ASTWriter::WriteAST(Sema &SemaRef, StringRef OutputFile,
4482                                      Module *WritingModule, StringRef isysroot,
4483                                      bool hasErrors,
4484                                      bool ShouldCacheASTInMemory) {
4485   WritingAST = true;
4486
4487   ASTHasCompilerErrors = hasErrors;
4488
4489   // Emit the file header.
4490   Stream.Emit((unsigned)'C', 8);
4491   Stream.Emit((unsigned)'P', 8);
4492   Stream.Emit((unsigned)'C', 8);
4493   Stream.Emit((unsigned)'H', 8);
4494
4495   WriteBlockInfoBlock();
4496
4497   Context = &SemaRef.Context;
4498   PP = &SemaRef.PP;
4499   this->WritingModule = WritingModule;
4500   ASTFileSignature Signature = WriteASTCore(SemaRef, isysroot, WritingModule);
4501   Context = nullptr;
4502   PP = nullptr;
4503   this->WritingModule = nullptr;
4504   this->BaseDirectory.clear();
4505
4506   WritingAST = false;
4507   if (ShouldCacheASTInMemory) {
4508     // Construct MemoryBuffer and update buffer manager.
4509     ModuleCache.addBuiltPCM(OutputFile,
4510                             llvm::MemoryBuffer::getMemBufferCopy(
4511                                 StringRef(Buffer.begin(), Buffer.size())));
4512   }
4513   return Signature;
4514 }
4515
4516 template<typename Vector>
4517 static void AddLazyVectorDecls(ASTWriter &Writer, Vector &Vec,
4518                                ASTWriter::RecordData &Record) {
4519   for (typename Vector::iterator I = Vec.begin(nullptr, true), E = Vec.end();
4520        I != E; ++I) {
4521     Writer.AddDeclRef(*I, Record);
4522   }
4523 }
4524
4525 ASTFileSignature ASTWriter::WriteASTCore(Sema &SemaRef, StringRef isysroot,
4526                                          Module *WritingModule) {
4527   using namespace llvm;
4528
4529   bool isModule = WritingModule != nullptr;
4530
4531   // Make sure that the AST reader knows to finalize itself.
4532   if (Chain)
4533     Chain->finalizeForWriting();
4534
4535   ASTContext &Context = SemaRef.Context;
4536   Preprocessor &PP = SemaRef.PP;
4537
4538   // Set up predefined declaration IDs.
4539   auto RegisterPredefDecl = [&] (Decl *D, PredefinedDeclIDs ID) {
4540     if (D) {
4541       assert(D->isCanonicalDecl() && "predefined decl is not canonical");
4542       DeclIDs[D] = ID;
4543     }
4544   };
4545   RegisterPredefDecl(Context.getTranslationUnitDecl(),
4546                      PREDEF_DECL_TRANSLATION_UNIT_ID);
4547   RegisterPredefDecl(Context.ObjCIdDecl, PREDEF_DECL_OBJC_ID_ID);
4548   RegisterPredefDecl(Context.ObjCSelDecl, PREDEF_DECL_OBJC_SEL_ID);
4549   RegisterPredefDecl(Context.ObjCClassDecl, PREDEF_DECL_OBJC_CLASS_ID);
4550   RegisterPredefDecl(Context.ObjCProtocolClassDecl,
4551                      PREDEF_DECL_OBJC_PROTOCOL_ID);
4552   RegisterPredefDecl(Context.Int128Decl, PREDEF_DECL_INT_128_ID);
4553   RegisterPredefDecl(Context.UInt128Decl, PREDEF_DECL_UNSIGNED_INT_128_ID);
4554   RegisterPredefDecl(Context.ObjCInstanceTypeDecl,
4555                      PREDEF_DECL_OBJC_INSTANCETYPE_ID);
4556   RegisterPredefDecl(Context.BuiltinVaListDecl, PREDEF_DECL_BUILTIN_VA_LIST_ID);
4557   RegisterPredefDecl(Context.VaListTagDecl, PREDEF_DECL_VA_LIST_TAG);
4558   RegisterPredefDecl(Context.BuiltinMSVaListDecl,
4559                      PREDEF_DECL_BUILTIN_MS_VA_LIST_ID);
4560   RegisterPredefDecl(Context.MSGuidTagDecl,
4561                      PREDEF_DECL_BUILTIN_MS_GUID_ID);
4562   RegisterPredefDecl(Context.ExternCContext, PREDEF_DECL_EXTERN_C_CONTEXT_ID);
4563   RegisterPredefDecl(Context.MakeIntegerSeqDecl,
4564                      PREDEF_DECL_MAKE_INTEGER_SEQ_ID);
4565   RegisterPredefDecl(Context.CFConstantStringTypeDecl,
4566                      PREDEF_DECL_CF_CONSTANT_STRING_ID);
4567   RegisterPredefDecl(Context.CFConstantStringTagDecl,
4568                      PREDEF_DECL_CF_CONSTANT_STRING_TAG_ID);
4569   RegisterPredefDecl(Context.TypePackElementDecl,
4570                      PREDEF_DECL_TYPE_PACK_ELEMENT_ID);
4571
4572   // Build a record containing all of the tentative definitions in this file, in
4573   // TentativeDefinitions order.  Generally, this record will be empty for
4574   // headers.
4575   RecordData TentativeDefinitions;
4576   AddLazyVectorDecls(*this, SemaRef.TentativeDefinitions, TentativeDefinitions);
4577
4578   // Build a record containing all of the file scoped decls in this file.
4579   RecordData UnusedFileScopedDecls;
4580   if (!isModule)
4581     AddLazyVectorDecls(*this, SemaRef.UnusedFileScopedDecls,
4582                        UnusedFileScopedDecls);
4583
4584   // Build a record containing all of the delegating constructors we still need
4585   // to resolve.
4586   RecordData DelegatingCtorDecls;
4587   if (!isModule)
4588     AddLazyVectorDecls(*this, SemaRef.DelegatingCtorDecls, DelegatingCtorDecls);
4589
4590   // Write the set of weak, undeclared identifiers. We always write the
4591   // entire table, since later PCH files in a PCH chain are only interested in
4592   // the results at the end of the chain.
4593   RecordData WeakUndeclaredIdentifiers;
4594   for (const auto &WeakUndeclaredIdentifierList :
4595        SemaRef.WeakUndeclaredIdentifiers) {
4596     const IdentifierInfo *const II = WeakUndeclaredIdentifierList.first;
4597     for (const auto &WI : WeakUndeclaredIdentifierList.second) {
4598       AddIdentifierRef(II, WeakUndeclaredIdentifiers);
4599       AddIdentifierRef(WI.getAlias(), WeakUndeclaredIdentifiers);
4600       AddSourceLocation(WI.getLocation(), WeakUndeclaredIdentifiers);
4601     }
4602   }
4603
4604   // Build a record containing all of the ext_vector declarations.
4605   RecordData ExtVectorDecls;
4606   AddLazyVectorDecls(*this, SemaRef.ExtVectorDecls, ExtVectorDecls);
4607
4608   // Build a record containing all of the VTable uses information.
4609   RecordData VTableUses;
4610   if (!SemaRef.VTableUses.empty()) {
4611     for (unsigned I = 0, N = SemaRef.VTableUses.size(); I != N; ++I) {
4612       AddDeclRef(SemaRef.VTableUses[I].first, VTableUses);
4613       AddSourceLocation(SemaRef.VTableUses[I].second, VTableUses);
4614       VTableUses.push_back(SemaRef.VTablesUsed[SemaRef.VTableUses[I].first]);
4615     }
4616   }
4617
4618   // Build a record containing all of the UnusedLocalTypedefNameCandidates.
4619   RecordData UnusedLocalTypedefNameCandidates;
4620   for (const TypedefNameDecl *TD : SemaRef.UnusedLocalTypedefNameCandidates)
4621     AddDeclRef(TD, UnusedLocalTypedefNameCandidates);
4622
4623   // Build a record containing all of pending implicit instantiations.
4624   RecordData PendingInstantiations;
4625   for (const auto &I : SemaRef.PendingInstantiations) {
4626     AddDeclRef(I.first, PendingInstantiations);
4627     AddSourceLocation(I.second, PendingInstantiations);
4628   }
4629   assert(SemaRef.PendingLocalImplicitInstantiations.empty() &&
4630          "There are local ones at end of translation unit!");
4631
4632   // Build a record containing some declaration references.
4633   RecordData SemaDeclRefs;
4634   if (SemaRef.StdNamespace || SemaRef.StdBadAlloc || SemaRef.StdAlignValT) {
4635     AddDeclRef(SemaRef.getStdNamespace(), SemaDeclRefs);
4636     AddDeclRef(SemaRef.getStdBadAlloc(), SemaDeclRefs);
4637     AddDeclRef(SemaRef.getStdAlignValT(), SemaDeclRefs);
4638   }
4639
4640   RecordData CUDASpecialDeclRefs;
4641   if (Context.getcudaConfigureCallDecl()) {
4642     AddDeclRef(Context.getcudaConfigureCallDecl(), CUDASpecialDeclRefs);
4643   }
4644
4645   // Build a record containing all of the known namespaces.
4646   RecordData KnownNamespaces;
4647   for (const auto &I : SemaRef.KnownNamespaces) {
4648     if (!I.second)
4649       AddDeclRef(I.first, KnownNamespaces);
4650   }
4651
4652   // Build a record of all used, undefined objects that require definitions.
4653   RecordData UndefinedButUsed;
4654
4655   SmallVector<std::pair<NamedDecl *, SourceLocation>, 16> Undefined;
4656   SemaRef.getUndefinedButUsed(Undefined);
4657   for (const auto &I : Undefined) {
4658     AddDeclRef(I.first, UndefinedButUsed);
4659     AddSourceLocation(I.second, UndefinedButUsed);
4660   }
4661
4662   // Build a record containing all delete-expressions that we would like to
4663   // analyze later in AST.
4664   RecordData DeleteExprsToAnalyze;
4665
4666   if (!isModule) {
4667     for (const auto &DeleteExprsInfo :
4668          SemaRef.getMismatchingDeleteExpressions()) {
4669       AddDeclRef(DeleteExprsInfo.first, DeleteExprsToAnalyze);
4670       DeleteExprsToAnalyze.push_back(DeleteExprsInfo.second.size());
4671       for (const auto &DeleteLoc : DeleteExprsInfo.second) {
4672         AddSourceLocation(DeleteLoc.first, DeleteExprsToAnalyze);
4673         DeleteExprsToAnalyze.push_back(DeleteLoc.second);
4674       }
4675     }
4676   }
4677
4678   // Write the control block
4679   WriteControlBlock(PP, Context, isysroot);
4680
4681   // Write the remaining AST contents.
4682   Stream.FlushToWord();
4683   ASTBlockRange.first = Stream.GetCurrentBitNo();
4684   Stream.EnterSubblock(AST_BLOCK_ID, 5);
4685   ASTBlockStartOffset = Stream.GetCurrentBitNo();
4686
4687   // This is so that older clang versions, before the introduction
4688   // of the control block, can read and reject the newer PCH format.
4689   {
4690     RecordData Record = {VERSION_MAJOR};
4691     Stream.EmitRecord(METADATA_OLD_FORMAT, Record);
4692   }
4693
4694   // Create a lexical update block containing all of the declarations in the
4695   // translation unit that do not come from other AST files.
4696   const TranslationUnitDecl *TU = Context.getTranslationUnitDecl();
4697   SmallVector<uint32_t, 128> NewGlobalKindDeclPairs;
4698   for (const auto *D : TU->noload_decls()) {
4699     if (!D->isFromASTFile()) {
4700       NewGlobalKindDeclPairs.push_back(D->getKind());
4701       NewGlobalKindDeclPairs.push_back(GetDeclRef(D));
4702     }
4703   }
4704
4705   auto Abv = std::make_shared<BitCodeAbbrev>();
4706   Abv->Add(llvm::BitCodeAbbrevOp(TU_UPDATE_LEXICAL));
4707   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Blob));
4708   unsigned TuUpdateLexicalAbbrev = Stream.EmitAbbrev(std::move(Abv));
4709   {
4710     RecordData::value_type Record[] = {TU_UPDATE_LEXICAL};
4711     Stream.EmitRecordWithBlob(TuUpdateLexicalAbbrev, Record,
4712                               bytes(NewGlobalKindDeclPairs));
4713   }
4714
4715   // And a visible updates block for the translation unit.
4716   Abv = std::make_shared<BitCodeAbbrev>();
4717   Abv->Add(llvm::BitCodeAbbrevOp(UPDATE_VISIBLE));
4718   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4719   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Blob));
4720   UpdateVisibleAbbrev = Stream.EmitAbbrev(std::move(Abv));
4721   WriteDeclContextVisibleUpdate(TU);
4722
4723   // If we have any extern "C" names, write out a visible update for them.
4724   if (Context.ExternCContext)
4725     WriteDeclContextVisibleUpdate(Context.ExternCContext);
4726
4727   // If the translation unit has an anonymous namespace, and we don't already
4728   // have an update block for it, write it as an update block.
4729   // FIXME: Why do we not do this if there's already an update block?
4730   if (NamespaceDecl *NS = TU->getAnonymousNamespace()) {
4731     ASTWriter::UpdateRecord &Record = DeclUpdates[TU];
4732     if (Record.empty())
4733       Record.push_back(DeclUpdate(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE, NS));
4734   }
4735
4736   // Add update records for all mangling numbers and static local numbers.
4737   // These aren't really update records, but this is a convenient way of
4738   // tagging this rare extra data onto the declarations.
4739   for (const auto &Number : Context.MangleNumbers)
4740     if (!Number.first->isFromASTFile())
4741       DeclUpdates[Number.first].push_back(DeclUpdate(UPD_MANGLING_NUMBER,
4742                                                      Number.second));
4743   for (const auto &Number : Context.StaticLocalNumbers)
4744     if (!Number.first->isFromASTFile())
4745       DeclUpdates[Number.first].push_back(DeclUpdate(UPD_STATIC_LOCAL_NUMBER,
4746                                                      Number.second));
4747
4748   // Make sure visible decls, added to DeclContexts previously loaded from
4749   // an AST file, are registered for serialization. Likewise for template
4750   // specializations added to imported templates.
4751   for (const auto *I : DeclsToEmitEvenIfUnreferenced) {
4752     GetDeclRef(I);
4753   }
4754
4755   // Make sure all decls associated with an identifier are registered for
4756   // serialization, if we're storing decls with identifiers.
4757   if (!WritingModule || !getLangOpts().CPlusPlus) {
4758     llvm::SmallVector<const IdentifierInfo*, 256> IIs;
4759     for (const auto &ID : PP.getIdentifierTable()) {
4760       const IdentifierInfo *II = ID.second;
4761       if (!Chain || !II->isFromAST() || II->hasChangedSinceDeserialization())
4762         IIs.push_back(II);
4763     }
4764     // Sort the identifiers to visit based on their name.
4765     llvm::sort(IIs, llvm::deref<std::less<>>());
4766     for (const IdentifierInfo *II : IIs) {
4767       for (IdentifierResolver::iterator D = SemaRef.IdResolver.begin(II),
4768                                      DEnd = SemaRef.IdResolver.end();
4769            D != DEnd; ++D) {
4770         GetDeclRef(*D);
4771       }
4772     }
4773   }
4774
4775   // For method pool in the module, if it contains an entry for a selector,
4776   // the entry should be complete, containing everything introduced by that
4777   // module and all modules it imports. It's possible that the entry is out of
4778   // date, so we need to pull in the new content here.
4779
4780   // It's possible that updateOutOfDateSelector can update SelectorIDs. To be
4781   // safe, we copy all selectors out.
4782   llvm::SmallVector<Selector, 256> AllSelectors;
4783   for (auto &SelectorAndID : SelectorIDs)
4784     AllSelectors.push_back(SelectorAndID.first);
4785   for (auto &Selector : AllSelectors)
4786     SemaRef.updateOutOfDateSelector(Selector);
4787
4788   // Form the record of special types.
4789   RecordData SpecialTypes;
4790   AddTypeRef(Context.getRawCFConstantStringType(), SpecialTypes);
4791   AddTypeRef(Context.getFILEType(), SpecialTypes);
4792   AddTypeRef(Context.getjmp_bufType(), SpecialTypes);
4793   AddTypeRef(Context.getsigjmp_bufType(), SpecialTypes);
4794   AddTypeRef(Context.ObjCIdRedefinitionType, SpecialTypes);
4795   AddTypeRef(Context.ObjCClassRedefinitionType, SpecialTypes);
4796   AddTypeRef(Context.ObjCSelRedefinitionType, SpecialTypes);
4797   AddTypeRef(Context.getucontext_tType(), SpecialTypes);
4798
4799   if (Chain) {
4800     // Write the mapping information describing our module dependencies and how
4801     // each of those modules were mapped into our own offset/ID space, so that
4802     // the reader can build the appropriate mapping to its own offset/ID space.
4803     // The map consists solely of a blob with the following format:
4804     // *(module-kind:i8
4805     //   module-name-len:i16 module-name:len*i8
4806     //   source-location-offset:i32
4807     //   identifier-id:i32
4808     //   preprocessed-entity-id:i32
4809     //   macro-definition-id:i32
4810     //   submodule-id:i32
4811     //   selector-id:i32
4812     //   declaration-id:i32
4813     //   c++-base-specifiers-id:i32
4814     //   type-id:i32)
4815     //
4816     // module-kind is the ModuleKind enum value. If it is MK_PrebuiltModule,
4817     // MK_ExplicitModule or MK_ImplicitModule, then the module-name is the
4818     // module name. Otherwise, it is the module file name.
4819     auto Abbrev = std::make_shared<BitCodeAbbrev>();
4820     Abbrev->Add(BitCodeAbbrevOp(MODULE_OFFSET_MAP));
4821     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
4822     unsigned ModuleOffsetMapAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
4823     SmallString<2048> Buffer;
4824     {
4825       llvm::raw_svector_ostream Out(Buffer);
4826       for (ModuleFile &M : Chain->ModuleMgr) {
4827         using namespace llvm::support;
4828
4829         endian::Writer LE(Out, little);
4830         LE.write<uint8_t>(static_cast<uint8_t>(M.Kind));
4831         StringRef Name = M.isModule() ? M.ModuleName : M.FileName;
4832         LE.write<uint16_t>(Name.size());
4833         Out.write(Name.data(), Name.size());
4834
4835         // Note: if a base ID was uint max, it would not be possible to load
4836         // another module after it or have more than one entity inside it.
4837         uint32_t None = std::numeric_limits<uint32_t>::max();
4838
4839         auto writeBaseIDOrNone = [&](auto BaseID, bool ShouldWrite) {
4840           assert(BaseID < std::numeric_limits<uint32_t>::max() && "base id too high");
4841           if (ShouldWrite)
4842             LE.write<uint32_t>(BaseID);
4843           else
4844             LE.write<uint32_t>(None);
4845         };
4846
4847         // These values should be unique within a chain, since they will be read
4848         // as keys into ContinuousRangeMaps.
4849         writeBaseIDOrNone(M.SLocEntryBaseOffset, M.LocalNumSLocEntries);
4850         writeBaseIDOrNone(M.BaseIdentifierID, M.LocalNumIdentifiers);
4851         writeBaseIDOrNone(M.BaseMacroID, M.LocalNumMacros);
4852         writeBaseIDOrNone(M.BasePreprocessedEntityID,
4853                           M.NumPreprocessedEntities);
4854         writeBaseIDOrNone(M.BaseSubmoduleID, M.LocalNumSubmodules);
4855         writeBaseIDOrNone(M.BaseSelectorID, M.LocalNumSelectors);
4856         writeBaseIDOrNone(M.BaseDeclID, M.LocalNumDecls);
4857         writeBaseIDOrNone(M.BaseTypeIndex, M.LocalNumTypes);
4858       }
4859     }
4860     RecordData::value_type Record[] = {MODULE_OFFSET_MAP};
4861     Stream.EmitRecordWithBlob(ModuleOffsetMapAbbrev, Record,
4862                               Buffer.data(), Buffer.size());
4863   }
4864
4865   // Build a record containing all of the DeclsToCheckForDeferredDiags.
4866   SmallVector<serialization::DeclID, 64> DeclsToCheckForDeferredDiags;
4867   for (auto *D : SemaRef.DeclsToCheckForDeferredDiags)
4868     DeclsToCheckForDeferredDiags.push_back(GetDeclRef(D));
4869
4870   RecordData DeclUpdatesOffsetsRecord;
4871
4872   // Keep writing types, declarations, and declaration update records
4873   // until we've emitted all of them.
4874   Stream.EnterSubblock(DECLTYPES_BLOCK_ID, /*bits for abbreviations*/5);
4875   DeclTypesBlockStartOffset = Stream.GetCurrentBitNo();
4876   WriteTypeAbbrevs();
4877   WriteDeclAbbrevs();
4878   do {
4879     WriteDeclUpdatesBlocks(DeclUpdatesOffsetsRecord);
4880     while (!DeclTypesToEmit.empty()) {
4881       DeclOrType DOT = DeclTypesToEmit.front();
4882       DeclTypesToEmit.pop();
4883       if (DOT.isType())
4884         WriteType(DOT.getType());
4885       else
4886         WriteDecl(Context, DOT.getDecl());
4887     }
4888   } while (!DeclUpdates.empty());
4889   Stream.ExitBlock();
4890
4891   DoneWritingDeclsAndTypes = true;
4892
4893   // These things can only be done once we've written out decls and types.
4894   WriteTypeDeclOffsets();
4895   if (!DeclUpdatesOffsetsRecord.empty())
4896     Stream.EmitRecord(DECL_UPDATE_OFFSETS, DeclUpdatesOffsetsRecord);
4897   WriteFileDeclIDsMap();
4898   WriteSourceManagerBlock(Context.getSourceManager(), PP);
4899   WriteComments();
4900   WritePreprocessor(PP, isModule);
4901   WriteHeaderSearch(PP.getHeaderSearchInfo());
4902   WriteSelectors(SemaRef);
4903   WriteReferencedSelectorsPool(SemaRef);
4904   WriteLateParsedTemplates(SemaRef);
4905   WriteIdentifierTable(PP, SemaRef.IdResolver, isModule);
4906   WriteFPPragmaOptions(SemaRef.CurFPFeatureOverrides());
4907   WriteOpenCLExtensions(SemaRef);
4908   WriteCUDAPragmas(SemaRef);
4909
4910   // If we're emitting a module, write out the submodule information.
4911   if (WritingModule)
4912     WriteSubmodules(WritingModule);
4913
4914   Stream.EmitRecord(SPECIAL_TYPES, SpecialTypes);
4915
4916   // Write the record containing external, unnamed definitions.
4917   if (!EagerlyDeserializedDecls.empty())
4918     Stream.EmitRecord(EAGERLY_DESERIALIZED_DECLS, EagerlyDeserializedDecls);
4919
4920   if (!ModularCodegenDecls.empty())
4921     Stream.EmitRecord(MODULAR_CODEGEN_DECLS, ModularCodegenDecls);
4922
4923   // Write the record containing tentative definitions.
4924   if (!TentativeDefinitions.empty())
4925     Stream.EmitRecord(TENTATIVE_DEFINITIONS, TentativeDefinitions);
4926
4927   // Write the record containing unused file scoped decls.
4928   if (!UnusedFileScopedDecls.empty())
4929     Stream.EmitRecord(UNUSED_FILESCOPED_DECLS, UnusedFileScopedDecls);
4930
4931   // Write the record containing weak undeclared identifiers.
4932   if (!WeakUndeclaredIdentifiers.empty())
4933     Stream.EmitRecord(WEAK_UNDECLARED_IDENTIFIERS,
4934                       WeakUndeclaredIdentifiers);
4935
4936   // Write the record containing ext_vector type names.
4937   if (!ExtVectorDecls.empty())
4938     Stream.EmitRecord(EXT_VECTOR_DECLS, ExtVectorDecls);
4939
4940   // Write the record containing VTable uses information.
4941   if (!VTableUses.empty())
4942     Stream.EmitRecord(VTABLE_USES, VTableUses);
4943
4944   // Write the record containing potentially unused local typedefs.
4945   if (!UnusedLocalTypedefNameCandidates.empty())
4946     Stream.EmitRecord(UNUSED_LOCAL_TYPEDEF_NAME_CANDIDATES,
4947                       UnusedLocalTypedefNameCandidates);
4948
4949   // Write the record containing pending implicit instantiations.
4950   if (!PendingInstantiations.empty())
4951     Stream.EmitRecord(PENDING_IMPLICIT_INSTANTIATIONS, PendingInstantiations);
4952
4953   // Write the record containing declaration references of Sema.
4954   if (!SemaDeclRefs.empty())
4955     Stream.EmitRecord(SEMA_DECL_REFS, SemaDeclRefs);
4956
4957   // Write the record containing decls to be checked for deferred diags.
4958   if (!DeclsToCheckForDeferredDiags.empty())
4959     Stream.EmitRecord(DECLS_TO_CHECK_FOR_DEFERRED_DIAGS,
4960         DeclsToCheckForDeferredDiags);
4961
4962   // Write the record containing CUDA-specific declaration references.
4963   if (!CUDASpecialDeclRefs.empty())
4964     Stream.EmitRecord(CUDA_SPECIAL_DECL_REFS, CUDASpecialDeclRefs);
4965
4966   // Write the delegating constructors.
4967   if (!DelegatingCtorDecls.empty())
4968     Stream.EmitRecord(DELEGATING_CTORS, DelegatingCtorDecls);
4969
4970   // Write the known namespaces.
4971   if (!KnownNamespaces.empty())
4972     Stream.EmitRecord(KNOWN_NAMESPACES, KnownNamespaces);
4973
4974   // Write the undefined internal functions and variables, and inline functions.
4975   if (!UndefinedButUsed.empty())
4976     Stream.EmitRecord(UNDEFINED_BUT_USED, UndefinedButUsed);
4977
4978   if (!DeleteExprsToAnalyze.empty())
4979     Stream.EmitRecord(DELETE_EXPRS_TO_ANALYZE, DeleteExprsToAnalyze);
4980
4981   // Write the visible updates to DeclContexts.
4982   for (auto *DC : UpdatedDeclContexts)
4983     WriteDeclContextVisibleUpdate(DC);
4984
4985   if (!WritingModule) {
4986     // Write the submodules that were imported, if any.
4987     struct ModuleInfo {
4988       uint64_t ID;
4989       Module *M;
4990       ModuleInfo(uint64_t ID, Module *M) : ID(ID), M(M) {}
4991     };
4992     llvm::SmallVector<ModuleInfo, 64> Imports;
4993     for (const auto *I : Context.local_imports()) {
4994       assert(SubmoduleIDs.find(I->getImportedModule()) != SubmoduleIDs.end());
4995       Imports.push_back(ModuleInfo(SubmoduleIDs[I->getImportedModule()],
4996                          I->getImportedModule()));
4997     }
4998
4999     if (!Imports.empty()) {
5000       auto Cmp = [](const ModuleInfo &A, const ModuleInfo &B) {
5001         return A.ID < B.ID;
5002       };
5003       auto Eq = [](const ModuleInfo &A, const ModuleInfo &B) {
5004         return A.ID == B.ID;
5005       };
5006
5007       // Sort and deduplicate module IDs.
5008       llvm::sort(Imports, Cmp);
5009       Imports.erase(std::unique(Imports.begin(), Imports.end(), Eq),
5010                     Imports.end());
5011
5012       RecordData ImportedModules;
5013       for (const auto &Import : Imports) {
5014         ImportedModules.push_back(Import.ID);
5015         // FIXME: If the module has macros imported then later has declarations
5016         // imported, this location won't be the right one as a location for the
5017         // declaration imports.
5018         AddSourceLocation(PP.getModuleImportLoc(Import.M), ImportedModules);
5019       }
5020
5021       Stream.EmitRecord(IMPORTED_MODULES, ImportedModules);
5022     }
5023   }
5024
5025   WriteObjCCategories();
5026   if(!WritingModule) {
5027     WriteOptimizePragmaOptions(SemaRef);
5028     WriteMSStructPragmaOptions(SemaRef);
5029     WriteMSPointersToMembersPragmaOptions(SemaRef);
5030   }
5031   WritePackPragmaOptions(SemaRef);
5032   WriteFloatControlPragmaOptions(SemaRef);
5033
5034   // Some simple statistics
5035   RecordData::value_type Record[] = {
5036       NumStatements, NumMacros, NumLexicalDeclContexts, NumVisibleDeclContexts};
5037   Stream.EmitRecord(STATISTICS, Record);
5038   Stream.ExitBlock();
5039   Stream.FlushToWord();
5040   ASTBlockRange.second = Stream.GetCurrentBitNo();
5041
5042   // Write the module file extension blocks.
5043   for (const auto &ExtWriter : ModuleFileExtensionWriters)
5044     WriteModuleFileExtension(SemaRef, *ExtWriter);
5045
5046   return writeUnhashedControlBlock(PP, Context);
5047 }
5048
5049 void ASTWriter::WriteDeclUpdatesBlocks(RecordDataImpl &OffsetsRecord) {
5050   if (DeclUpdates.empty())
5051     return;
5052
5053   DeclUpdateMap LocalUpdates;
5054   LocalUpdates.swap(DeclUpdates);
5055
5056   for (auto &DeclUpdate : LocalUpdates) {
5057     const Decl *D = DeclUpdate.first;
5058
5059     bool HasUpdatedBody = false;
5060     RecordData RecordData;
5061     ASTRecordWriter Record(*this, RecordData);
5062     for (auto &Update : DeclUpdate.second) {
5063       DeclUpdateKind Kind = (DeclUpdateKind)Update.getKind();
5064
5065       // An updated body is emitted last, so that the reader doesn't need
5066       // to skip over the lazy body to reach statements for other records.
5067       if (Kind == UPD_CXX_ADDED_FUNCTION_DEFINITION)
5068         HasUpdatedBody = true;
5069       else
5070         Record.push_back(Kind);
5071
5072       switch (Kind) {
5073       case UPD_CXX_ADDED_IMPLICIT_MEMBER:
5074       case UPD_CXX_ADDED_TEMPLATE_SPECIALIZATION:
5075       case UPD_CXX_ADDED_ANONYMOUS_NAMESPACE:
5076         assert(Update.getDecl() && "no decl to add?");
5077         Record.push_back(GetDeclRef(Update.getDecl()));
5078         break;
5079
5080       case UPD_CXX_ADDED_FUNCTION_DEFINITION:
5081         break;
5082
5083       case UPD_CXX_POINT_OF_INSTANTIATION:
5084         // FIXME: Do we need to also save the template specialization kind here?
5085         Record.AddSourceLocation(Update.getLoc());
5086         break;
5087
5088       case UPD_CXX_ADDED_VAR_DEFINITION: {
5089         const VarDecl *VD = cast<VarDecl>(D);
5090         Record.push_back(VD->isInline());
5091         Record.push_back(VD->isInlineSpecified());
5092         Record.AddVarDeclInit(VD);
5093         break;
5094       }
5095
5096       case UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT:
5097         Record.AddStmt(const_cast<Expr *>(
5098             cast<ParmVarDecl>(Update.getDecl())->getDefaultArg()));
5099         break;
5100
5101       case UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER:
5102         Record.AddStmt(
5103             cast<FieldDecl>(Update.getDecl())->getInClassInitializer());
5104         break;
5105
5106       case UPD_CXX_INSTANTIATED_CLASS_DEFINITION: {
5107         auto *RD = cast<CXXRecordDecl>(D);
5108         UpdatedDeclContexts.insert(RD->getPrimaryContext());
5109         Record.push_back(RD->isParamDestroyedInCallee());
5110         Record.push_back(RD->getArgPassingRestrictions());
5111         Record.AddCXXDefinitionData(RD);
5112         Record.AddOffset(WriteDeclContextLexicalBlock(
5113             *Context, const_cast<CXXRecordDecl *>(RD)));
5114
5115         // This state is sometimes updated by template instantiation, when we
5116         // switch from the specialization referring to the template declaration
5117         // to it referring to the template definition.
5118         if (auto *MSInfo = RD->getMemberSpecializationInfo()) {
5119           Record.push_back(MSInfo->getTemplateSpecializationKind());
5120           Record.AddSourceLocation(MSInfo->getPointOfInstantiation());
5121         } else {
5122           auto *Spec = cast<ClassTemplateSpecializationDecl>(RD);
5123           Record.push_back(Spec->getTemplateSpecializationKind());
5124           Record.AddSourceLocation(Spec->getPointOfInstantiation());
5125
5126           // The instantiation might have been resolved to a partial
5127           // specialization. If so, record which one.
5128           auto From = Spec->getInstantiatedFrom();
5129           if (auto PartialSpec =
5130                 From.dyn_cast<ClassTemplatePartialSpecializationDecl*>()) {
5131             Record.push_back(true);
5132             Record.AddDeclRef(PartialSpec);
5133             Record.AddTemplateArgumentList(
5134                 &Spec->getTemplateInstantiationArgs());
5135           } else {
5136             Record.push_back(false);
5137           }
5138         }
5139         Record.push_back(RD->getTagKind());
5140         Record.AddSourceLocation(RD->getLocation());
5141         Record.AddSourceLocation(RD->getBeginLoc());
5142         Record.AddSourceRange(RD->getBraceRange());
5143
5144         // Instantiation may change attributes; write them all out afresh.
5145         Record.push_back(D->hasAttrs());
5146         if (D->hasAttrs())
5147           Record.AddAttributes(D->getAttrs());
5148
5149         // FIXME: Ensure we don't get here for explicit instantiations.
5150         break;
5151       }
5152
5153       case UPD_CXX_RESOLVED_DTOR_DELETE:
5154         Record.AddDeclRef(Update.getDecl());
5155         Record.AddStmt(cast<CXXDestructorDecl>(D)->getOperatorDeleteThisArg());
5156         break;
5157
5158       case UPD_CXX_RESOLVED_EXCEPTION_SPEC: {
5159         auto prototype =
5160           cast<FunctionDecl>(D)->getType()->castAs<FunctionProtoType>();
5161         Record.writeExceptionSpecInfo(prototype->getExceptionSpecInfo());
5162         break;
5163       }
5164
5165       case UPD_CXX_DEDUCED_RETURN_TYPE:
5166         Record.push_back(GetOrCreateTypeID(Update.getType()));
5167         break;
5168
5169       case UPD_DECL_MARKED_USED:
5170         break;
5171
5172       case UPD_MANGLING_NUMBER:
5173       case UPD_STATIC_LOCAL_NUMBER:
5174         Record.push_back(Update.getNumber());
5175         break;
5176
5177       case UPD_DECL_MARKED_OPENMP_THREADPRIVATE:
5178         Record.AddSourceRange(
5179             D->getAttr<OMPThreadPrivateDeclAttr>()->getRange());
5180         break;
5181
5182       case UPD_DECL_MARKED_OPENMP_ALLOCATE: {
5183         auto *A = D->getAttr<OMPAllocateDeclAttr>();
5184         Record.push_back(A->getAllocatorType());
5185         Record.AddStmt(A->getAllocator());
5186         Record.AddStmt(A->getAlignment());
5187         Record.AddSourceRange(A->getRange());
5188         break;
5189       }
5190
5191       case UPD_DECL_MARKED_OPENMP_DECLARETARGET:
5192         Record.push_back(D->getAttr<OMPDeclareTargetDeclAttr>()->getMapType());
5193         Record.AddSourceRange(
5194             D->getAttr<OMPDeclareTargetDeclAttr>()->getRange());
5195         break;
5196
5197       case UPD_DECL_EXPORTED:
5198         Record.push_back(getSubmoduleID(Update.getModule()));
5199         break;
5200
5201       case UPD_ADDED_ATTR_TO_RECORD:
5202         Record.AddAttributes(llvm::makeArrayRef(Update.getAttr()));
5203         break;
5204       }
5205     }
5206
5207     if (HasUpdatedBody) {
5208       const auto *Def = cast<FunctionDecl>(D);
5209       Record.push_back(UPD_CXX_ADDED_FUNCTION_DEFINITION);
5210       Record.push_back(Def->isInlined());
5211       Record.AddSourceLocation(Def->getInnerLocStart());
5212       Record.AddFunctionDefinition(Def);
5213     }
5214
5215     OffsetsRecord.push_back(GetDeclRef(D));
5216     OffsetsRecord.push_back(Record.Emit(DECL_UPDATES));
5217   }
5218 }
5219
5220 void ASTWriter::AddAlignPackInfo(const Sema::AlignPackInfo &Info,
5221                                  RecordDataImpl &Record) {
5222   uint32_t Raw = Sema::AlignPackInfo::getRawEncoding(Info);
5223   Record.push_back(Raw);
5224 }
5225
5226 void ASTWriter::AddSourceLocation(SourceLocation Loc, RecordDataImpl &Record,
5227                                   SourceLocationSequence *Seq) {
5228   Record.push_back(SourceLocationEncoding::encode(Loc, Seq));
5229 }
5230
5231 void ASTWriter::AddSourceRange(SourceRange Range, RecordDataImpl &Record,
5232                                SourceLocationSequence *Seq) {
5233   AddSourceLocation(Range.getBegin(), Record, Seq);
5234   AddSourceLocation(Range.getEnd(), Record, Seq);
5235 }
5236
5237 void ASTRecordWriter::AddAPFloat(const llvm::APFloat &Value) {
5238   AddAPInt(Value.bitcastToAPInt());
5239 }
5240
5241 void ASTWriter::AddIdentifierRef(const IdentifierInfo *II, RecordDataImpl &Record) {
5242   Record.push_back(getIdentifierRef(II));
5243 }
5244
5245 IdentID ASTWriter::getIdentifierRef(const IdentifierInfo *II) {
5246   if (!II)
5247     return 0;
5248
5249   IdentID &ID = IdentifierIDs[II];
5250   if (ID == 0)
5251     ID = NextIdentID++;
5252   return ID;
5253 }
5254
5255 MacroID ASTWriter::getMacroRef(MacroInfo *MI, const IdentifierInfo *Name) {
5256   // Don't emit builtin macros like __LINE__ to the AST file unless they
5257   // have been redefined by the header (in which case they are not
5258   // isBuiltinMacro).
5259   if (!MI || MI->isBuiltinMacro())
5260     return 0;
5261
5262   MacroID &ID = MacroIDs[MI];
5263   if (ID == 0) {
5264     ID = NextMacroID++;
5265     MacroInfoToEmitData Info = { Name, MI, ID };
5266     MacroInfosToEmit.push_back(Info);
5267   }
5268   return ID;
5269 }
5270
5271 MacroID ASTWriter::getMacroID(MacroInfo *MI) {
5272   if (!MI || MI->isBuiltinMacro())
5273     return 0;
5274
5275   assert(MacroIDs.find(MI) != MacroIDs.end() && "Macro not emitted!");
5276   return MacroIDs[MI];
5277 }
5278
5279 uint32_t ASTWriter::getMacroDirectivesOffset(const IdentifierInfo *Name) {
5280   return IdentMacroDirectivesOffsetMap.lookup(Name);
5281 }
5282
5283 void ASTRecordWriter::AddSelectorRef(const Selector SelRef) {
5284   Record->push_back(Writer->getSelectorRef(SelRef));
5285 }
5286
5287 SelectorID ASTWriter::getSelectorRef(Selector Sel) {
5288   if (Sel.getAsOpaquePtr() == nullptr) {
5289     return 0;
5290   }
5291
5292   SelectorID SID = SelectorIDs[Sel];
5293   if (SID == 0 && Chain) {
5294     // This might trigger a ReadSelector callback, which will set the ID for
5295     // this selector.
5296     Chain->LoadSelector(Sel);
5297     SID = SelectorIDs[Sel];
5298   }
5299   if (SID == 0) {
5300     SID = NextSelectorID++;
5301     SelectorIDs[Sel] = SID;
5302   }
5303   return SID;
5304 }
5305
5306 void ASTRecordWriter::AddCXXTemporary(const CXXTemporary *Temp) {
5307   AddDeclRef(Temp->getDestructor());
5308 }
5309
5310 void ASTRecordWriter::AddTemplateArgumentLocInfo(
5311     TemplateArgument::ArgKind Kind, const TemplateArgumentLocInfo &Arg) {
5312   switch (Kind) {
5313   case TemplateArgument::Expression:
5314     AddStmt(Arg.getAsExpr());
5315     break;
5316   case TemplateArgument::Type:
5317     AddTypeSourceInfo(Arg.getAsTypeSourceInfo());
5318     break;
5319   case TemplateArgument::Template:
5320     AddNestedNameSpecifierLoc(Arg.getTemplateQualifierLoc());
5321     AddSourceLocation(Arg.getTemplateNameLoc());
5322     break;
5323   case TemplateArgument::TemplateExpansion:
5324     AddNestedNameSpecifierLoc(Arg.getTemplateQualifierLoc());
5325     AddSourceLocation(Arg.getTemplateNameLoc());
5326     AddSourceLocation(Arg.getTemplateEllipsisLoc());
5327     break;
5328   case TemplateArgument::Null:
5329   case TemplateArgument::Integral:
5330   case TemplateArgument::Declaration:
5331   case TemplateArgument::NullPtr:
5332   case TemplateArgument::Pack:
5333     // FIXME: Is this right?
5334     break;
5335   }
5336 }
5337
5338 void ASTRecordWriter::AddTemplateArgumentLoc(const TemplateArgumentLoc &Arg) {
5339   AddTemplateArgument(Arg.getArgument());
5340
5341   if (Arg.getArgument().getKind() == TemplateArgument::Expression) {
5342     bool InfoHasSameExpr
5343       = Arg.getArgument().getAsExpr() == Arg.getLocInfo().getAsExpr();
5344     Record->push_back(InfoHasSameExpr);
5345     if (InfoHasSameExpr)
5346       return; // Avoid storing the same expr twice.
5347   }
5348   AddTemplateArgumentLocInfo(Arg.getArgument().getKind(), Arg.getLocInfo());
5349 }
5350
5351 void ASTRecordWriter::AddTypeSourceInfo(TypeSourceInfo *TInfo) {
5352   if (!TInfo) {
5353     AddTypeRef(QualType());
5354     return;
5355   }
5356
5357   AddTypeRef(TInfo->getType());
5358   AddTypeLoc(TInfo->getTypeLoc());
5359 }
5360
5361 void ASTRecordWriter::AddTypeLoc(TypeLoc TL, LocSeq *OuterSeq) {
5362   LocSeq::State Seq(OuterSeq);
5363   TypeLocWriter TLW(*this, Seq);
5364   for (; !TL.isNull(); TL = TL.getNextTypeLoc())
5365     TLW.Visit(TL);
5366 }
5367
5368 void ASTWriter::AddTypeRef(QualType T, RecordDataImpl &Record) {
5369   Record.push_back(GetOrCreateTypeID(T));
5370 }
5371
5372 TypeID ASTWriter::GetOrCreateTypeID(QualType T) {
5373   assert(Context);
5374   return MakeTypeID(*Context, T, [&](QualType T) -> TypeIdx {
5375     if (T.isNull())
5376       return TypeIdx();
5377     assert(!T.getLocalFastQualifiers());
5378
5379     TypeIdx &Idx = TypeIdxs[T];
5380     if (Idx.getIndex() == 0) {
5381       if (DoneWritingDeclsAndTypes) {
5382         assert(0 && "New type seen after serializing all the types to emit!");
5383         return TypeIdx();
5384       }
5385
5386       // We haven't seen this type before. Assign it a new ID and put it
5387       // into the queue of types to emit.
5388       Idx = TypeIdx(NextTypeID++);
5389       DeclTypesToEmit.push(T);
5390     }
5391     return Idx;
5392   });
5393 }
5394
5395 TypeID ASTWriter::getTypeID(QualType T) const {
5396   assert(Context);
5397   return MakeTypeID(*Context, T, [&](QualType T) -> TypeIdx {
5398     if (T.isNull())
5399       return TypeIdx();
5400     assert(!T.getLocalFastQualifiers());
5401
5402     TypeIdxMap::const_iterator I = TypeIdxs.find(T);
5403     assert(I != TypeIdxs.end() && "Type not emitted!");
5404     return I->second;
5405   });
5406 }
5407
5408 void ASTWriter::AddDeclRef(const Decl *D, RecordDataImpl &Record) {
5409   Record.push_back(GetDeclRef(D));
5410 }
5411
5412 DeclID ASTWriter::GetDeclRef(const Decl *D) {
5413   assert(WritingAST && "Cannot request a declaration ID before AST writing");
5414
5415   if (!D) {
5416     return 0;
5417   }
5418
5419   // If D comes from an AST file, its declaration ID is already known and
5420   // fixed.
5421   if (D->isFromASTFile())
5422     return D->getGlobalID();
5423
5424   assert(!(reinterpret_cast<uintptr_t>(D) & 0x01) && "Invalid decl pointer");
5425   DeclID &ID = DeclIDs[D];
5426   if (ID == 0) {
5427     if (DoneWritingDeclsAndTypes) {
5428       assert(0 && "New decl seen after serializing all the decls to emit!");
5429       return 0;
5430     }
5431
5432     // We haven't seen this declaration before. Give it a new ID and
5433     // enqueue it in the list of declarations to emit.
5434     ID = NextDeclID++;
5435     DeclTypesToEmit.push(const_cast<Decl *>(D));
5436   }
5437
5438   return ID;
5439 }
5440
5441 DeclID ASTWriter::getDeclID(const Decl *D) {
5442   if (!D)
5443     return 0;
5444
5445   // If D comes from an AST file, its declaration ID is already known and
5446   // fixed.
5447   if (D->isFromASTFile())
5448     return D->getGlobalID();
5449
5450   assert(DeclIDs.find(D) != DeclIDs.end() && "Declaration not emitted!");
5451   return DeclIDs[D];
5452 }
5453
5454 void ASTWriter::associateDeclWithFile(const Decl *D, DeclID ID) {
5455   assert(ID);
5456   assert(D);
5457
5458   SourceLocation Loc = D->getLocation();
5459   if (Loc.isInvalid())
5460     return;
5461
5462   // We only keep track of the file-level declarations of each file.
5463   if (!D->getLexicalDeclContext()->isFileContext())
5464     return;
5465   // FIXME: ParmVarDecls that are part of a function type of a parameter of
5466   // a function/objc method, should not have TU as lexical context.
5467   // TemplateTemplateParmDecls that are part of an alias template, should not
5468   // have TU as lexical context.
5469   if (isa<ParmVarDecl>(D) || isa<TemplateTemplateParmDecl>(D))
5470     return;
5471
5472   SourceManager &SM = Context->getSourceManager();
5473   SourceLocation FileLoc = SM.getFileLoc(Loc);
5474   assert(SM.isLocalSourceLocation(FileLoc));
5475   FileID FID;
5476   unsigned Offset;
5477   std::tie(FID, Offset) = SM.getDecomposedLoc(FileLoc);
5478   if (FID.isInvalid())
5479     return;
5480   assert(SM.getSLocEntry(FID).isFile());
5481
5482   std::unique_ptr<DeclIDInFileInfo> &Info = FileDeclIDs[FID];
5483   if (!Info)
5484     Info = std::make_unique<DeclIDInFileInfo>();
5485
5486   std::pair<unsigned, serialization::DeclID> LocDecl(Offset, ID);
5487   LocDeclIDsTy &Decls = Info->DeclIDs;
5488   Decls.push_back(LocDecl);
5489 }
5490
5491 unsigned ASTWriter::getAnonymousDeclarationNumber(const NamedDecl *D) {
5492   assert(needsAnonymousDeclarationNumber(D) &&
5493          "expected an anonymous declaration");
5494
5495   // Number the anonymous declarations within this context, if we've not
5496   // already done so.
5497   auto It = AnonymousDeclarationNumbers.find(D);
5498   if (It == AnonymousDeclarationNumbers.end()) {
5499     auto *DC = D->getLexicalDeclContext();
5500     numberAnonymousDeclsWithin(DC, [&](const NamedDecl *ND, unsigned Number) {
5501       AnonymousDeclarationNumbers[ND] = Number;
5502     });
5503
5504     It = AnonymousDeclarationNumbers.find(D);
5505     assert(It != AnonymousDeclarationNumbers.end() &&
5506            "declaration not found within its lexical context");
5507   }
5508
5509   return It->second;
5510 }
5511
5512 void ASTRecordWriter::AddDeclarationNameLoc(const DeclarationNameLoc &DNLoc,
5513                                             DeclarationName Name) {
5514   switch (Name.getNameKind()) {
5515   case DeclarationName::CXXConstructorName:
5516   case DeclarationName::CXXDestructorName:
5517   case DeclarationName::CXXConversionFunctionName:
5518     AddTypeSourceInfo(DNLoc.getNamedTypeInfo());
5519     break;
5520
5521   case DeclarationName::CXXOperatorName:
5522     AddSourceRange(DNLoc.getCXXOperatorNameRange());
5523     break;
5524
5525   case DeclarationName::CXXLiteralOperatorName:
5526     AddSourceLocation(DNLoc.getCXXLiteralOperatorNameLoc());
5527     break;
5528
5529   case DeclarationName::Identifier:
5530   case DeclarationName::ObjCZeroArgSelector:
5531   case DeclarationName::ObjCOneArgSelector:
5532   case DeclarationName::ObjCMultiArgSelector:
5533   case DeclarationName::CXXUsingDirective:
5534   case DeclarationName::CXXDeductionGuideName:
5535     break;
5536   }
5537 }
5538
5539 void ASTRecordWriter::AddDeclarationNameInfo(
5540     const DeclarationNameInfo &NameInfo) {
5541   AddDeclarationName(NameInfo.getName());
5542   AddSourceLocation(NameInfo.getLoc());
5543   AddDeclarationNameLoc(NameInfo.getInfo(), NameInfo.getName());
5544 }
5545
5546 void ASTRecordWriter::AddQualifierInfo(const QualifierInfo &Info) {
5547   AddNestedNameSpecifierLoc(Info.QualifierLoc);
5548   Record->push_back(Info.NumTemplParamLists);
5549   for (unsigned i = 0, e = Info.NumTemplParamLists; i != e; ++i)
5550     AddTemplateParameterList(Info.TemplParamLists[i]);
5551 }
5552
5553 void ASTRecordWriter::AddNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS) {
5554   // Nested name specifiers usually aren't too long. I think that 8 would
5555   // typically accommodate the vast majority.
5556   SmallVector<NestedNameSpecifierLoc , 8> NestedNames;
5557
5558   // Push each of the nested-name-specifiers's onto a stack for
5559   // serialization in reverse order.
5560   while (NNS) {
5561     NestedNames.push_back(NNS);
5562     NNS = NNS.getPrefix();
5563   }
5564
5565   Record->push_back(NestedNames.size());
5566   while(!NestedNames.empty()) {
5567     NNS = NestedNames.pop_back_val();
5568     NestedNameSpecifier::SpecifierKind Kind
5569       = NNS.getNestedNameSpecifier()->getKind();
5570     Record->push_back(Kind);
5571     switch (Kind) {
5572     case NestedNameSpecifier::Identifier:
5573       AddIdentifierRef(NNS.getNestedNameSpecifier()->getAsIdentifier());
5574       AddSourceRange(NNS.getLocalSourceRange());
5575       break;
5576
5577     case NestedNameSpecifier::Namespace:
5578       AddDeclRef(NNS.getNestedNameSpecifier()->getAsNamespace());
5579       AddSourceRange(NNS.getLocalSourceRange());
5580       break;
5581
5582     case NestedNameSpecifier::NamespaceAlias:
5583       AddDeclRef(NNS.getNestedNameSpecifier()->getAsNamespaceAlias());
5584       AddSourceRange(NNS.getLocalSourceRange());
5585       break;
5586
5587     case NestedNameSpecifier::TypeSpec:
5588     case NestedNameSpecifier::TypeSpecWithTemplate:
5589       Record->push_back(Kind == NestedNameSpecifier::TypeSpecWithTemplate);
5590       AddTypeRef(NNS.getTypeLoc().getType());
5591       AddTypeLoc(NNS.getTypeLoc());
5592       AddSourceLocation(NNS.getLocalSourceRange().getEnd());
5593       break;
5594
5595     case NestedNameSpecifier::Global:
5596       AddSourceLocation(NNS.getLocalSourceRange().getEnd());
5597       break;
5598
5599     case NestedNameSpecifier::Super:
5600       AddDeclRef(NNS.getNestedNameSpecifier()->getAsRecordDecl());
5601       AddSourceRange(NNS.getLocalSourceRange());
5602       break;
5603     }
5604   }
5605 }
5606
5607 void ASTRecordWriter::AddTemplateParameterList(
5608     const TemplateParameterList *TemplateParams) {
5609   assert(TemplateParams && "No TemplateParams!");
5610   AddSourceLocation(TemplateParams->getTemplateLoc());
5611   AddSourceLocation(TemplateParams->getLAngleLoc());
5612   AddSourceLocation(TemplateParams->getRAngleLoc());
5613
5614   Record->push_back(TemplateParams->size());
5615   for (const auto &P : *TemplateParams)
5616     AddDeclRef(P);
5617   if (const Expr *RequiresClause = TemplateParams->getRequiresClause()) {
5618     Record->push_back(true);
5619     AddStmt(const_cast<Expr*>(RequiresClause));
5620   } else {
5621     Record->push_back(false);
5622   }
5623 }
5624
5625 /// Emit a template argument list.
5626 void ASTRecordWriter::AddTemplateArgumentList(
5627     const TemplateArgumentList *TemplateArgs) {
5628   assert(TemplateArgs && "No TemplateArgs!");
5629   Record->push_back(TemplateArgs->size());
5630   for (int i = 0, e = TemplateArgs->size(); i != e; ++i)
5631     AddTemplateArgument(TemplateArgs->get(i));
5632 }
5633
5634 void ASTRecordWriter::AddASTTemplateArgumentListInfo(
5635     const ASTTemplateArgumentListInfo *ASTTemplArgList) {
5636   assert(ASTTemplArgList && "No ASTTemplArgList!");
5637   AddSourceLocation(ASTTemplArgList->LAngleLoc);
5638   AddSourceLocation(ASTTemplArgList->RAngleLoc);
5639   Record->push_back(ASTTemplArgList->NumTemplateArgs);
5640   const TemplateArgumentLoc *TemplArgs = ASTTemplArgList->getTemplateArgs();
5641   for (int i = 0, e = ASTTemplArgList->NumTemplateArgs; i != e; ++i)
5642     AddTemplateArgumentLoc(TemplArgs[i]);
5643 }
5644
5645 void ASTRecordWriter::AddUnresolvedSet(const ASTUnresolvedSet &Set) {
5646   Record->push_back(Set.size());
5647   for (ASTUnresolvedSet::const_iterator
5648          I = Set.begin(), E = Set.end(); I != E; ++I) {
5649     AddDeclRef(I.getDecl());
5650     Record->push_back(I.getAccess());
5651   }
5652 }
5653
5654 // FIXME: Move this out of the main ASTRecordWriter interface.
5655 void ASTRecordWriter::AddCXXBaseSpecifier(const CXXBaseSpecifier &Base) {
5656   Record->push_back(Base.isVirtual());
5657   Record->push_back(Base.isBaseOfClass());
5658   Record->push_back(Base.getAccessSpecifierAsWritten());
5659   Record->push_back(Base.getInheritConstructors());
5660   AddTypeSourceInfo(Base.getTypeSourceInfo());
5661   AddSourceRange(Base.getSourceRange());
5662   AddSourceLocation(Base.isPackExpansion()? Base.getEllipsisLoc()
5663                                           : SourceLocation());
5664 }
5665
5666 static uint64_t EmitCXXBaseSpecifiers(ASTWriter &W,
5667                                       ArrayRef<CXXBaseSpecifier> Bases) {
5668   ASTWriter::RecordData Record;
5669   ASTRecordWriter Writer(W, Record);
5670   Writer.push_back(Bases.size());
5671
5672   for (auto &Base : Bases)
5673     Writer.AddCXXBaseSpecifier(Base);
5674
5675   return Writer.Emit(serialization::DECL_CXX_BASE_SPECIFIERS);
5676 }
5677
5678 // FIXME: Move this out of the main ASTRecordWriter interface.
5679 void ASTRecordWriter::AddCXXBaseSpecifiers(ArrayRef<CXXBaseSpecifier> Bases) {
5680   AddOffset(EmitCXXBaseSpecifiers(*Writer, Bases));
5681 }
5682
5683 static uint64_t
5684 EmitCXXCtorInitializers(ASTWriter &W,
5685                         ArrayRef<CXXCtorInitializer *> CtorInits) {
5686   ASTWriter::RecordData Record;
5687   ASTRecordWriter Writer(W, Record);
5688   Writer.push_back(CtorInits.size());
5689
5690   for (auto *Init : CtorInits) {
5691     if (Init->isBaseInitializer()) {
5692       Writer.push_back(CTOR_INITIALIZER_BASE);
5693       Writer.AddTypeSourceInfo(Init->getTypeSourceInfo());
5694       Writer.push_back(Init->isBaseVirtual());
5695     } else if (Init->isDelegatingInitializer()) {
5696       Writer.push_back(CTOR_INITIALIZER_DELEGATING);
5697       Writer.AddTypeSourceInfo(Init->getTypeSourceInfo());
5698     } else if (Init->isMemberInitializer()){
5699       Writer.push_back(CTOR_INITIALIZER_MEMBER);
5700       Writer.AddDeclRef(Init->getMember());
5701     } else {
5702       Writer.push_back(CTOR_INITIALIZER_INDIRECT_MEMBER);
5703       Writer.AddDeclRef(Init->getIndirectMember());
5704     }
5705
5706     Writer.AddSourceLocation(Init->getMemberLocation());
5707     Writer.AddStmt(Init->getInit());
5708     Writer.AddSourceLocation(Init->getLParenLoc());
5709     Writer.AddSourceLocation(Init->getRParenLoc());
5710     Writer.push_back(Init->isWritten());
5711     if (Init->isWritten())
5712       Writer.push_back(Init->getSourceOrder());
5713   }
5714
5715   return Writer.Emit(serialization::DECL_CXX_CTOR_INITIALIZERS);
5716 }
5717
5718 // FIXME: Move this out of the main ASTRecordWriter interface.
5719 void ASTRecordWriter::AddCXXCtorInitializers(
5720     ArrayRef<CXXCtorInitializer *> CtorInits) {
5721   AddOffset(EmitCXXCtorInitializers(*Writer, CtorInits));
5722 }
5723
5724 void ASTRecordWriter::AddCXXDefinitionData(const CXXRecordDecl *D) {
5725   auto &Data = D->data();
5726   Record->push_back(Data.IsLambda);
5727
5728   #define FIELD(Name, Width, Merge) \
5729   Record->push_back(Data.Name);
5730   #include "clang/AST/CXXRecordDeclDefinitionBits.def"
5731
5732   // getODRHash will compute the ODRHash if it has not been previously computed.
5733   Record->push_back(D->getODRHash());
5734   bool ModulesDebugInfo =
5735       Writer->Context->getLangOpts().ModulesDebugInfo && !D->isDependentType();
5736   Record->push_back(ModulesDebugInfo);
5737   if (ModulesDebugInfo)
5738     Writer->ModularCodegenDecls.push_back(Writer->GetDeclRef(D));
5739
5740   // IsLambda bit is already saved.
5741
5742   Record->push_back(Data.NumBases);
5743   if (Data.NumBases > 0)
5744     AddCXXBaseSpecifiers(Data.bases());
5745
5746   // FIXME: Make VBases lazily computed when needed to avoid storing them.
5747   Record->push_back(Data.NumVBases);
5748   if (Data.NumVBases > 0)
5749     AddCXXBaseSpecifiers(Data.vbases());
5750
5751   AddUnresolvedSet(Data.Conversions.get(*Writer->Context));
5752   Record->push_back(Data.ComputedVisibleConversions);
5753   if (Data.ComputedVisibleConversions)
5754     AddUnresolvedSet(Data.VisibleConversions.get(*Writer->Context));
5755   // Data.Definition is the owning decl, no need to write it.
5756   AddDeclRef(D->getFirstFriend());
5757
5758   // Add lambda-specific data.
5759   if (Data.IsLambda) {
5760     auto &Lambda = D->getLambdaData();
5761     Record->push_back(Lambda.DependencyKind);
5762     Record->push_back(Lambda.IsGenericLambda);
5763     Record->push_back(Lambda.CaptureDefault);
5764     Record->push_back(Lambda.NumCaptures);
5765     Record->push_back(Lambda.NumExplicitCaptures);
5766     Record->push_back(Lambda.HasKnownInternalLinkage);
5767     Record->push_back(Lambda.ManglingNumber);
5768     Record->push_back(D->getDeviceLambdaManglingNumber());
5769     AddDeclRef(D->getLambdaContextDecl());
5770     AddTypeSourceInfo(Lambda.MethodTyInfo);
5771     for (unsigned I = 0, N = Lambda.NumCaptures; I != N; ++I) {
5772       const LambdaCapture &Capture = Lambda.Captures[I];
5773       AddSourceLocation(Capture.getLocation());
5774       Record->push_back(Capture.isImplicit());
5775       Record->push_back(Capture.getCaptureKind());
5776       switch (Capture.getCaptureKind()) {
5777       case LCK_StarThis:
5778       case LCK_This:
5779       case LCK_VLAType:
5780         break;
5781       case LCK_ByCopy:
5782       case LCK_ByRef:
5783         ValueDecl *Var =
5784             Capture.capturesVariable() ? Capture.getCapturedVar() : nullptr;
5785         AddDeclRef(Var);
5786         AddSourceLocation(Capture.isPackExpansion() ? Capture.getEllipsisLoc()
5787                                                     : SourceLocation());
5788         break;
5789       }
5790     }
5791   }
5792 }
5793
5794 void ASTRecordWriter::AddVarDeclInit(const VarDecl *VD) {
5795   const Expr *Init = VD->getInit();
5796   if (!Init) {
5797     push_back(0);
5798     return;
5799   }
5800
5801   unsigned Val = 1;
5802   if (EvaluatedStmt *ES = VD->getEvaluatedStmt()) {
5803     Val |= (ES->HasConstantInitialization ? 2 : 0);
5804     Val |= (ES->HasConstantDestruction ? 4 : 0);
5805     // FIXME: Also emit the constant initializer value.
5806   }
5807   push_back(Val);
5808   writeStmtRef(Init);
5809 }
5810
5811 void ASTWriter::ReaderInitialized(ASTReader *Reader) {
5812   assert(Reader && "Cannot remove chain");
5813   assert((!Chain || Chain == Reader) && "Cannot replace chain");
5814   assert(FirstDeclID == NextDeclID &&
5815          FirstTypeID == NextTypeID &&
5816          FirstIdentID == NextIdentID &&
5817          FirstMacroID == NextMacroID &&
5818          FirstSubmoduleID == NextSubmoduleID &&
5819          FirstSelectorID == NextSelectorID &&
5820          "Setting chain after writing has started.");
5821
5822   Chain = Reader;
5823
5824   // Note, this will get called multiple times, once one the reader starts up
5825   // and again each time it's done reading a PCH or module.
5826   FirstDeclID = NUM_PREDEF_DECL_IDS + Chain->getTotalNumDecls();
5827   FirstTypeID = NUM_PREDEF_TYPE_IDS + Chain->getTotalNumTypes();
5828   FirstIdentID = NUM_PREDEF_IDENT_IDS + Chain->getTotalNumIdentifiers();
5829   FirstMacroID = NUM_PREDEF_MACRO_IDS + Chain->getTotalNumMacros();
5830   FirstSubmoduleID = NUM_PREDEF_SUBMODULE_IDS + Chain->getTotalNumSubmodules();
5831   FirstSelectorID = NUM_PREDEF_SELECTOR_IDS + Chain->getTotalNumSelectors();
5832   NextDeclID = FirstDeclID;
5833   NextTypeID = FirstTypeID;
5834   NextIdentID = FirstIdentID;
5835   NextMacroID = FirstMacroID;
5836   NextSelectorID = FirstSelectorID;
5837   NextSubmoduleID = FirstSubmoduleID;
5838 }
5839
5840 void ASTWriter::IdentifierRead(IdentID ID, IdentifierInfo *II) {
5841   // Always keep the highest ID. See \p TypeRead() for more information.
5842   IdentID &StoredID = IdentifierIDs[II];
5843   if (ID > StoredID)
5844     StoredID = ID;
5845 }
5846
5847 void ASTWriter::MacroRead(serialization::MacroID ID, MacroInfo *MI) {
5848   // Always keep the highest ID. See \p TypeRead() for more information.
5849   MacroID &StoredID = MacroIDs[MI];
5850   if (ID > StoredID)
5851     StoredID = ID;
5852 }
5853
5854 void ASTWriter::TypeRead(TypeIdx Idx, QualType T) {
5855   // Always take the highest-numbered type index. This copes with an interesting
5856   // case for chained AST writing where we schedule writing the type and then,
5857   // later, deserialize the type from another AST. In this case, we want to
5858   // keep the higher-numbered entry so that we can properly write it out to
5859   // the AST file.
5860   TypeIdx &StoredIdx = TypeIdxs[T];
5861   if (Idx.getIndex() >= StoredIdx.getIndex())
5862     StoredIdx = Idx;
5863 }
5864
5865 void ASTWriter::SelectorRead(SelectorID ID, Selector S) {
5866   // Always keep the highest ID. See \p TypeRead() for more information.
5867   SelectorID &StoredID = SelectorIDs[S];
5868   if (ID > StoredID)
5869     StoredID = ID;
5870 }
5871
5872 void ASTWriter::MacroDefinitionRead(serialization::PreprocessedEntityID ID,
5873                                     MacroDefinitionRecord *MD) {
5874   assert(MacroDefinitions.find(MD) == MacroDefinitions.end());
5875   MacroDefinitions[MD] = ID;
5876 }
5877
5878 void ASTWriter::ModuleRead(serialization::SubmoduleID ID, Module *Mod) {
5879   assert(SubmoduleIDs.find(Mod) == SubmoduleIDs.end());
5880   SubmoduleIDs[Mod] = ID;
5881 }
5882
5883 void ASTWriter::CompletedTagDefinition(const TagDecl *D) {
5884   if (Chain && Chain->isProcessingUpdateRecords()) return;
5885   assert(D->isCompleteDefinition());
5886   assert(!WritingAST && "Already writing the AST!");
5887   if (auto *RD = dyn_cast<CXXRecordDecl>(D)) {
5888     // We are interested when a PCH decl is modified.
5889     if (RD->isFromASTFile()) {
5890       // A forward reference was mutated into a definition. Rewrite it.
5891       // FIXME: This happens during template instantiation, should we
5892       // have created a new definition decl instead ?
5893       assert(isTemplateInstantiation(RD->getTemplateSpecializationKind()) &&
5894              "completed a tag from another module but not by instantiation?");
5895       DeclUpdates[RD].push_back(
5896           DeclUpdate(UPD_CXX_INSTANTIATED_CLASS_DEFINITION));
5897     }
5898   }
5899 }
5900
5901 static bool isImportedDeclContext(ASTReader *Chain, const Decl *D) {
5902   if (D->isFromASTFile())
5903     return true;
5904
5905   // The predefined __va_list_tag struct is imported if we imported any decls.
5906   // FIXME: This is a gross hack.
5907   return D == D->getASTContext().getVaListTagDecl();
5908 }
5909
5910 void ASTWriter::AddedVisibleDecl(const DeclContext *DC, const Decl *D) {
5911   if (Chain && Chain->isProcessingUpdateRecords()) return;
5912   assert(DC->isLookupContext() &&
5913           "Should not add lookup results to non-lookup contexts!");
5914
5915   // TU is handled elsewhere.
5916   if (isa<TranslationUnitDecl>(DC))
5917     return;
5918
5919   // Namespaces are handled elsewhere, except for template instantiations of
5920   // FunctionTemplateDecls in namespaces. We are interested in cases where the
5921   // local instantiations are added to an imported context. Only happens when
5922   // adding ADL lookup candidates, for example templated friends.
5923   if (isa<NamespaceDecl>(DC) && D->getFriendObjectKind() == Decl::FOK_None &&
5924       !isa<FunctionTemplateDecl>(D))
5925     return;
5926
5927   // We're only interested in cases where a local declaration is added to an
5928   // imported context.
5929   if (D->isFromASTFile() || !isImportedDeclContext(Chain, cast<Decl>(DC)))
5930     return;
5931
5932   assert(DC == DC->getPrimaryContext() && "added to non-primary context");
5933   assert(!getDefinitiveDeclContext(DC) && "DeclContext not definitive!");
5934   assert(!WritingAST && "Already writing the AST!");
5935   if (UpdatedDeclContexts.insert(DC) && !cast<Decl>(DC)->isFromASTFile()) {
5936     // We're adding a visible declaration to a predefined decl context. Ensure
5937     // that we write out all of its lookup results so we don't get a nasty
5938     // surprise when we try to emit its lookup table.
5939     llvm::append_range(DeclsToEmitEvenIfUnreferenced, DC->decls());
5940   }
5941   DeclsToEmitEvenIfUnreferenced.push_back(D);
5942 }
5943
5944 void ASTWriter::AddedCXXImplicitMember(const CXXRecordDecl *RD, const Decl *D) {
5945   if (Chain && Chain->isProcessingUpdateRecords()) return;
5946   assert(D->isImplicit());
5947
5948   // We're only interested in cases where a local declaration is added to an
5949   // imported context.
5950   if (D->isFromASTFile() || !isImportedDeclContext(Chain, RD))
5951     return;
5952
5953   if (!isa<CXXMethodDecl>(D))
5954     return;
5955
5956   // A decl coming from PCH was modified.
5957   assert(RD->isCompleteDefinition());
5958   assert(!WritingAST && "Already writing the AST!");
5959   DeclUpdates[RD].push_back(DeclUpdate(UPD_CXX_ADDED_IMPLICIT_MEMBER, D));
5960 }
5961
5962 void ASTWriter::ResolvedExceptionSpec(const FunctionDecl *FD) {
5963   if (Chain && Chain->isProcessingUpdateRecords()) return;
5964   assert(!DoneWritingDeclsAndTypes && "Already done writing updates!");
5965   if (!Chain) return;
5966   Chain->forEachImportedKeyDecl(FD, [&](const Decl *D) {
5967     // If we don't already know the exception specification for this redecl
5968     // chain, add an update record for it.
5969     if (isUnresolvedExceptionSpec(cast<FunctionDecl>(D)
5970                                       ->getType()
5971                                       ->castAs<FunctionProtoType>()
5972                                       ->getExceptionSpecType()))
5973       DeclUpdates[D].push_back(UPD_CXX_RESOLVED_EXCEPTION_SPEC);
5974   });
5975 }
5976
5977 void ASTWriter::DeducedReturnType(const FunctionDecl *FD, QualType ReturnType) {
5978   if (Chain && Chain->isProcessingUpdateRecords()) return;
5979   assert(!WritingAST && "Already writing the AST!");
5980   if (!Chain) return;
5981   Chain->forEachImportedKeyDecl(FD, [&](const Decl *D) {
5982     DeclUpdates[D].push_back(
5983         DeclUpdate(UPD_CXX_DEDUCED_RETURN_TYPE, ReturnType));
5984   });
5985 }
5986
5987 void ASTWriter::ResolvedOperatorDelete(const CXXDestructorDecl *DD,
5988                                        const FunctionDecl *Delete,
5989                                        Expr *ThisArg) {
5990   if (Chain && Chain->isProcessingUpdateRecords()) return;
5991   assert(!WritingAST && "Already writing the AST!");
5992   assert(Delete && "Not given an operator delete");
5993   if (!Chain) return;
5994   Chain->forEachImportedKeyDecl(DD, [&](const Decl *D) {
5995     DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_RESOLVED_DTOR_DELETE, Delete));
5996   });
5997 }
5998
5999 void ASTWriter::CompletedImplicitDefinition(const FunctionDecl *D) {
6000   if (Chain && Chain->isProcessingUpdateRecords()) return;
6001   assert(!WritingAST && "Already writing the AST!");
6002   if (!D->isFromASTFile())
6003     return; // Declaration not imported from PCH.
6004
6005   // Implicit function decl from a PCH was defined.
6006   DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_ADDED_FUNCTION_DEFINITION));
6007 }
6008
6009 void ASTWriter::VariableDefinitionInstantiated(const VarDecl *D) {
6010   if (Chain && Chain->isProcessingUpdateRecords()) return;
6011   assert(!WritingAST && "Already writing the AST!");
6012   if (!D->isFromASTFile())
6013     return;
6014
6015   DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_ADDED_VAR_DEFINITION));
6016 }
6017
6018 void ASTWriter::FunctionDefinitionInstantiated(const FunctionDecl *D) {
6019   if (Chain && Chain->isProcessingUpdateRecords()) return;
6020   assert(!WritingAST && "Already writing the AST!");
6021   if (!D->isFromASTFile())
6022     return;
6023
6024   DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_ADDED_FUNCTION_DEFINITION));
6025 }
6026
6027 void ASTWriter::InstantiationRequested(const ValueDecl *D) {
6028   if (Chain && Chain->isProcessingUpdateRecords()) return;
6029   assert(!WritingAST && "Already writing the AST!");
6030   if (!D->isFromASTFile())
6031     return;
6032
6033   // Since the actual instantiation is delayed, this really means that we need
6034   // to update the instantiation location.
6035   SourceLocation POI;
6036   if (auto *VD = dyn_cast<VarDecl>(D))
6037     POI = VD->getPointOfInstantiation();
6038   else
6039     POI = cast<FunctionDecl>(D)->getPointOfInstantiation();
6040   DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_POINT_OF_INSTANTIATION, POI));
6041 }
6042
6043 void ASTWriter::DefaultArgumentInstantiated(const ParmVarDecl *D) {
6044   if (Chain && Chain->isProcessingUpdateRecords()) return;
6045   assert(!WritingAST && "Already writing the AST!");
6046   if (!D->isFromASTFile())
6047     return;
6048
6049   DeclUpdates[D].push_back(
6050       DeclUpdate(UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT, D));
6051 }
6052
6053 void ASTWriter::DefaultMemberInitializerInstantiated(const FieldDecl *D) {
6054   assert(!WritingAST && "Already writing the AST!");
6055   if (!D->isFromASTFile())
6056     return;
6057
6058   DeclUpdates[D].push_back(
6059       DeclUpdate(UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER, D));
6060 }
6061
6062 void ASTWriter::AddedObjCCategoryToInterface(const ObjCCategoryDecl *CatD,
6063                                              const ObjCInterfaceDecl *IFD) {
6064   if (Chain && Chain->isProcessingUpdateRecords()) return;
6065   assert(!WritingAST && "Already writing the AST!");
6066   if (!IFD->isFromASTFile())
6067     return; // Declaration not imported from PCH.
6068
6069   assert(IFD->getDefinition() && "Category on a class without a definition?");
6070   ObjCClassesWithCategories.insert(
6071     const_cast<ObjCInterfaceDecl *>(IFD->getDefinition()));
6072 }
6073
6074 void ASTWriter::DeclarationMarkedUsed(const Decl *D) {
6075   if (Chain && Chain->isProcessingUpdateRecords()) return;
6076   assert(!WritingAST && "Already writing the AST!");
6077
6078   // If there is *any* declaration of the entity that's not from an AST file,
6079   // we can skip writing the update record. We make sure that isUsed() triggers
6080   // completion of the redeclaration chain of the entity.
6081   for (auto Prev = D->getMostRecentDecl(); Prev; Prev = Prev->getPreviousDecl())
6082     if (IsLocalDecl(Prev))
6083       return;
6084
6085   DeclUpdates[D].push_back(DeclUpdate(UPD_DECL_MARKED_USED));
6086 }
6087
6088 void ASTWriter::DeclarationMarkedOpenMPThreadPrivate(const Decl *D) {
6089   if (Chain && Chain->isProcessingUpdateRecords()) return;
6090   assert(!WritingAST && "Already writing the AST!");
6091   if (!D->isFromASTFile())
6092     return;
6093
6094   DeclUpdates[D].push_back(DeclUpdate(UPD_DECL_MARKED_OPENMP_THREADPRIVATE));
6095 }
6096
6097 void ASTWriter::DeclarationMarkedOpenMPAllocate(const Decl *D, const Attr *A) {
6098   if (Chain && Chain->isProcessingUpdateRecords()) return;
6099   assert(!WritingAST && "Already writing the AST!");
6100   if (!D->isFromASTFile())
6101     return;
6102
6103   DeclUpdates[D].push_back(DeclUpdate(UPD_DECL_MARKED_OPENMP_ALLOCATE, A));
6104 }
6105
6106 void ASTWriter::DeclarationMarkedOpenMPDeclareTarget(const Decl *D,
6107                                                      const Attr *Attr) {
6108   if (Chain && Chain->isProcessingUpdateRecords()) return;
6109   assert(!WritingAST && "Already writing the AST!");
6110   if (!D->isFromASTFile())
6111     return;
6112
6113   DeclUpdates[D].push_back(
6114       DeclUpdate(UPD_DECL_MARKED_OPENMP_DECLARETARGET, Attr));
6115 }
6116
6117 void ASTWriter::RedefinedHiddenDefinition(const NamedDecl *D, Module *M) {
6118   if (Chain && Chain->isProcessingUpdateRecords()) return;
6119   assert(!WritingAST && "Already writing the AST!");
6120   assert(!D->isUnconditionallyVisible() && "expected a hidden declaration");
6121   DeclUpdates[D].push_back(DeclUpdate(UPD_DECL_EXPORTED, M));
6122 }
6123
6124 void ASTWriter::AddedAttributeToRecord(const Attr *Attr,
6125                                        const RecordDecl *Record) {
6126   if (Chain && Chain->isProcessingUpdateRecords()) return;
6127   assert(!WritingAST && "Already writing the AST!");
6128   if (!Record->isFromASTFile())
6129     return;
6130   DeclUpdates[Record].push_back(DeclUpdate(UPD_ADDED_ATTR_TO_RECORD, Attr));
6131 }
6132
6133 void ASTWriter::AddedCXXTemplateSpecialization(
6134     const ClassTemplateDecl *TD, const ClassTemplateSpecializationDecl *D) {
6135   assert(!WritingAST && "Already writing the AST!");
6136
6137   if (!TD->getFirstDecl()->isFromASTFile())
6138     return;
6139   if (Chain && Chain->isProcessingUpdateRecords())
6140     return;
6141
6142   DeclsToEmitEvenIfUnreferenced.push_back(D);
6143 }
6144
6145 void ASTWriter::AddedCXXTemplateSpecialization(
6146     const VarTemplateDecl *TD, const VarTemplateSpecializationDecl *D) {
6147   assert(!WritingAST && "Already writing the AST!");
6148
6149   if (!TD->getFirstDecl()->isFromASTFile())
6150     return;
6151   if (Chain && Chain->isProcessingUpdateRecords())
6152     return;
6153
6154   DeclsToEmitEvenIfUnreferenced.push_back(D);
6155 }
6156
6157 void ASTWriter::AddedCXXTemplateSpecialization(const FunctionTemplateDecl *TD,
6158                                                const FunctionDecl *D) {
6159   assert(!WritingAST && "Already writing the AST!");
6160
6161   if (!TD->getFirstDecl()->isFromASTFile())
6162     return;
6163   if (Chain && Chain->isProcessingUpdateRecords())
6164     return;
6165
6166   DeclsToEmitEvenIfUnreferenced.push_back(D);
6167 }
6168
6169 //===----------------------------------------------------------------------===//
6170 //// OMPClause Serialization
6171 ////===----------------------------------------------------------------------===//
6172
6173 namespace {
6174
6175 class OMPClauseWriter : public OMPClauseVisitor<OMPClauseWriter> {
6176   ASTRecordWriter &Record;
6177
6178 public:
6179   OMPClauseWriter(ASTRecordWriter &Record) : Record(Record) {}
6180 #define GEN_CLANG_CLAUSE_CLASS
6181 #define CLAUSE_CLASS(Enum, Str, Class) void Visit##Class(Class *S);
6182 #include "llvm/Frontend/OpenMP/OMP.inc"
6183   void writeClause(OMPClause *C);
6184   void VisitOMPClauseWithPreInit(OMPClauseWithPreInit *C);
6185   void VisitOMPClauseWithPostUpdate(OMPClauseWithPostUpdate *C);
6186 };
6187
6188 }
6189
6190 void ASTRecordWriter::writeOMPClause(OMPClause *C) {
6191   OMPClauseWriter(*this).writeClause(C);
6192 }
6193
6194 void OMPClauseWriter::writeClause(OMPClause *C) {
6195   Record.push_back(unsigned(C->getClauseKind()));
6196   Visit(C);
6197   Record.AddSourceLocation(C->getBeginLoc());
6198   Record.AddSourceLocation(C->getEndLoc());
6199 }
6200
6201 void OMPClauseWriter::VisitOMPClauseWithPreInit(OMPClauseWithPreInit *C) {
6202   Record.push_back(uint64_t(C->getCaptureRegion()));
6203   Record.AddStmt(C->getPreInitStmt());
6204 }
6205
6206 void OMPClauseWriter::VisitOMPClauseWithPostUpdate(OMPClauseWithPostUpdate *C) {
6207   VisitOMPClauseWithPreInit(C);
6208   Record.AddStmt(C->getPostUpdateExpr());
6209 }
6210
6211 void OMPClauseWriter::VisitOMPIfClause(OMPIfClause *C) {
6212   VisitOMPClauseWithPreInit(C);
6213   Record.push_back(uint64_t(C->getNameModifier()));
6214   Record.AddSourceLocation(C->getNameModifierLoc());
6215   Record.AddSourceLocation(C->getColonLoc());
6216   Record.AddStmt(C->getCondition());
6217   Record.AddSourceLocation(C->getLParenLoc());
6218 }
6219
6220 void OMPClauseWriter::VisitOMPFinalClause(OMPFinalClause *C) {
6221   VisitOMPClauseWithPreInit(C);
6222   Record.AddStmt(C->getCondition());
6223   Record.AddSourceLocation(C->getLParenLoc());
6224 }
6225
6226 void OMPClauseWriter::VisitOMPNumThreadsClause(OMPNumThreadsClause *C) {
6227   VisitOMPClauseWithPreInit(C);
6228   Record.AddStmt(C->getNumThreads());
6229   Record.AddSourceLocation(C->getLParenLoc());
6230 }
6231
6232 void OMPClauseWriter::VisitOMPSafelenClause(OMPSafelenClause *C) {
6233   Record.AddStmt(C->getSafelen());
6234   Record.AddSourceLocation(C->getLParenLoc());
6235 }
6236
6237 void OMPClauseWriter::VisitOMPSimdlenClause(OMPSimdlenClause *C) {
6238   Record.AddStmt(C->getSimdlen());
6239   Record.AddSourceLocation(C->getLParenLoc());
6240 }
6241
6242 void OMPClauseWriter::VisitOMPSizesClause(OMPSizesClause *C) {
6243   Record.push_back(C->getNumSizes());
6244   for (Expr *Size : C->getSizesRefs())
6245     Record.AddStmt(Size);
6246   Record.AddSourceLocation(C->getLParenLoc());
6247 }
6248
6249 void OMPClauseWriter::VisitOMPFullClause(OMPFullClause *C) {}
6250
6251 void OMPClauseWriter::VisitOMPPartialClause(OMPPartialClause *C) {
6252   Record.AddStmt(C->getFactor());
6253   Record.AddSourceLocation(C->getLParenLoc());
6254 }
6255
6256 void OMPClauseWriter::VisitOMPAllocatorClause(OMPAllocatorClause *C) {
6257   Record.AddStmt(C->getAllocator());
6258   Record.AddSourceLocation(C->getLParenLoc());
6259 }
6260
6261 void OMPClauseWriter::VisitOMPCollapseClause(OMPCollapseClause *C) {
6262   Record.AddStmt(C->getNumForLoops());
6263   Record.AddSourceLocation(C->getLParenLoc());
6264 }
6265
6266 void OMPClauseWriter::VisitOMPDetachClause(OMPDetachClause *C) {
6267   Record.AddStmt(C->getEventHandler());
6268   Record.AddSourceLocation(C->getLParenLoc());
6269 }
6270
6271 void OMPClauseWriter::VisitOMPDefaultClause(OMPDefaultClause *C) {
6272   Record.push_back(unsigned(C->getDefaultKind()));
6273   Record.AddSourceLocation(C->getLParenLoc());
6274   Record.AddSourceLocation(C->getDefaultKindKwLoc());
6275 }
6276
6277 void OMPClauseWriter::VisitOMPProcBindClause(OMPProcBindClause *C) {
6278   Record.push_back(unsigned(C->getProcBindKind()));
6279   Record.AddSourceLocation(C->getLParenLoc());
6280   Record.AddSourceLocation(C->getProcBindKindKwLoc());
6281 }
6282
6283 void OMPClauseWriter::VisitOMPScheduleClause(OMPScheduleClause *C) {
6284   VisitOMPClauseWithPreInit(C);
6285   Record.push_back(C->getScheduleKind());
6286   Record.push_back(C->getFirstScheduleModifier());
6287   Record.push_back(C->getSecondScheduleModifier());
6288   Record.AddStmt(C->getChunkSize());
6289   Record.AddSourceLocation(C->getLParenLoc());
6290   Record.AddSourceLocation(C->getFirstScheduleModifierLoc());
6291   Record.AddSourceLocation(C->getSecondScheduleModifierLoc());
6292   Record.AddSourceLocation(C->getScheduleKindLoc());
6293   Record.AddSourceLocation(C->getCommaLoc());
6294 }
6295
6296 void OMPClauseWriter::VisitOMPOrderedClause(OMPOrderedClause *C) {
6297   Record.push_back(C->getLoopNumIterations().size());
6298   Record.AddStmt(C->getNumForLoops());
6299   for (Expr *NumIter : C->getLoopNumIterations())
6300     Record.AddStmt(NumIter);
6301   for (unsigned I = 0, E = C->getLoopNumIterations().size(); I <E; ++I)
6302     Record.AddStmt(C->getLoopCounter(I));
6303   Record.AddSourceLocation(C->getLParenLoc());
6304 }
6305
6306 void OMPClauseWriter::VisitOMPNowaitClause(OMPNowaitClause *) {}
6307
6308 void OMPClauseWriter::VisitOMPUntiedClause(OMPUntiedClause *) {}
6309
6310 void OMPClauseWriter::VisitOMPMergeableClause(OMPMergeableClause *) {}
6311
6312 void OMPClauseWriter::VisitOMPReadClause(OMPReadClause *) {}
6313
6314 void OMPClauseWriter::VisitOMPWriteClause(OMPWriteClause *) {}
6315
6316 void OMPClauseWriter::VisitOMPUpdateClause(OMPUpdateClause *C) {
6317   Record.push_back(C->isExtended() ? 1 : 0);
6318   if (C->isExtended()) {
6319     Record.AddSourceLocation(C->getLParenLoc());
6320     Record.AddSourceLocation(C->getArgumentLoc());
6321     Record.writeEnum(C->getDependencyKind());
6322   }
6323 }
6324
6325 void OMPClauseWriter::VisitOMPCaptureClause(OMPCaptureClause *) {}
6326
6327 void OMPClauseWriter::VisitOMPCompareClause(OMPCompareClause *) {}
6328
6329 void OMPClauseWriter::VisitOMPSeqCstClause(OMPSeqCstClause *) {}
6330
6331 void OMPClauseWriter::VisitOMPAcqRelClause(OMPAcqRelClause *) {}
6332
6333 void OMPClauseWriter::VisitOMPAcquireClause(OMPAcquireClause *) {}
6334
6335 void OMPClauseWriter::VisitOMPReleaseClause(OMPReleaseClause *) {}
6336
6337 void OMPClauseWriter::VisitOMPRelaxedClause(OMPRelaxedClause *) {}
6338
6339 void OMPClauseWriter::VisitOMPThreadsClause(OMPThreadsClause *) {}
6340
6341 void OMPClauseWriter::VisitOMPSIMDClause(OMPSIMDClause *) {}
6342
6343 void OMPClauseWriter::VisitOMPNogroupClause(OMPNogroupClause *) {}
6344
6345 void OMPClauseWriter::VisitOMPInitClause(OMPInitClause *C) {
6346   Record.push_back(C->varlist_size());
6347   for (Expr *VE : C->varlists())
6348     Record.AddStmt(VE);
6349   Record.writeBool(C->getIsTarget());
6350   Record.writeBool(C->getIsTargetSync());
6351   Record.AddSourceLocation(C->getLParenLoc());
6352   Record.AddSourceLocation(C->getVarLoc());
6353 }
6354
6355 void OMPClauseWriter::VisitOMPUseClause(OMPUseClause *C) {
6356   Record.AddStmt(C->getInteropVar());
6357   Record.AddSourceLocation(C->getLParenLoc());
6358   Record.AddSourceLocation(C->getVarLoc());
6359 }
6360
6361 void OMPClauseWriter::VisitOMPDestroyClause(OMPDestroyClause *C) {
6362   Record.AddStmt(C->getInteropVar());
6363   Record.AddSourceLocation(C->getLParenLoc());
6364   Record.AddSourceLocation(C->getVarLoc());
6365 }
6366
6367 void OMPClauseWriter::VisitOMPNovariantsClause(OMPNovariantsClause *C) {
6368   VisitOMPClauseWithPreInit(C);
6369   Record.AddStmt(C->getCondition());
6370   Record.AddSourceLocation(C->getLParenLoc());
6371 }
6372
6373 void OMPClauseWriter::VisitOMPNocontextClause(OMPNocontextClause *C) {
6374   VisitOMPClauseWithPreInit(C);
6375   Record.AddStmt(C->getCondition());
6376   Record.AddSourceLocation(C->getLParenLoc());
6377 }
6378
6379 void OMPClauseWriter::VisitOMPFilterClause(OMPFilterClause *C) {
6380   VisitOMPClauseWithPreInit(C);
6381   Record.AddStmt(C->getThreadID());
6382   Record.AddSourceLocation(C->getLParenLoc());
6383 }
6384
6385 void OMPClauseWriter::VisitOMPAlignClause(OMPAlignClause *C) {
6386   Record.AddStmt(C->getAlignment());
6387   Record.AddSourceLocation(C->getLParenLoc());
6388 }
6389
6390 void OMPClauseWriter::VisitOMPPrivateClause(OMPPrivateClause *C) {
6391   Record.push_back(C->varlist_size());
6392   Record.AddSourceLocation(C->getLParenLoc());
6393   for (auto *VE : C->varlists()) {
6394     Record.AddStmt(VE);
6395   }
6396   for (auto *VE : C->private_copies()) {
6397     Record.AddStmt(VE);
6398   }
6399 }
6400
6401 void OMPClauseWriter::VisitOMPFirstprivateClause(OMPFirstprivateClause *C) {
6402   Record.push_back(C->varlist_size());
6403   VisitOMPClauseWithPreInit(C);
6404   Record.AddSourceLocation(C->getLParenLoc());
6405   for (auto *VE : C->varlists()) {
6406     Record.AddStmt(VE);
6407   }
6408   for (auto *VE : C->private_copies()) {
6409     Record.AddStmt(VE);
6410   }
6411   for (auto *VE : C->inits()) {
6412     Record.AddStmt(VE);
6413   }
6414 }
6415
6416 void OMPClauseWriter::VisitOMPLastprivateClause(OMPLastprivateClause *C) {
6417   Record.push_back(C->varlist_size());
6418   VisitOMPClauseWithPostUpdate(C);
6419   Record.AddSourceLocation(C->getLParenLoc());
6420   Record.writeEnum(C->getKind());
6421   Record.AddSourceLocation(C->getKindLoc());
6422   Record.AddSourceLocation(C->getColonLoc());
6423   for (auto *VE : C->varlists())
6424     Record.AddStmt(VE);
6425   for (auto *E : C->private_copies())
6426     Record.AddStmt(E);
6427   for (auto *E : C->source_exprs())
6428     Record.AddStmt(E);
6429   for (auto *E : C->destination_exprs())
6430     Record.AddStmt(E);
6431   for (auto *E : C->assignment_ops())
6432     Record.AddStmt(E);
6433 }
6434
6435 void OMPClauseWriter::VisitOMPSharedClause(OMPSharedClause *C) {
6436   Record.push_back(C->varlist_size());
6437   Record.AddSourceLocation(C->getLParenLoc());
6438   for (auto *VE : C->varlists())
6439     Record.AddStmt(VE);
6440 }
6441
6442 void OMPClauseWriter::VisitOMPReductionClause(OMPReductionClause *C) {
6443   Record.push_back(C->varlist_size());
6444   Record.writeEnum(C->getModifier());
6445   VisitOMPClauseWithPostUpdate(C);
6446   Record.AddSourceLocation(C->getLParenLoc());
6447   Record.AddSourceLocation(C->getModifierLoc());
6448   Record.AddSourceLocation(C->getColonLoc());
6449   Record.AddNestedNameSpecifierLoc(C->getQualifierLoc());
6450   Record.AddDeclarationNameInfo(C->getNameInfo());
6451   for (auto *VE : C->varlists())
6452     Record.AddStmt(VE);
6453   for (auto *VE : C->privates())
6454     Record.AddStmt(VE);
6455   for (auto *E : C->lhs_exprs())
6456     Record.AddStmt(E);
6457   for (auto *E : C->rhs_exprs())
6458     Record.AddStmt(E);
6459   for (auto *E : C->reduction_ops())
6460     Record.AddStmt(E);
6461   if (C->getModifier() == clang::OMPC_REDUCTION_inscan) {
6462     for (auto *E : C->copy_ops())
6463       Record.AddStmt(E);
6464     for (auto *E : C->copy_array_temps())
6465       Record.AddStmt(E);
6466     for (auto *E : C->copy_array_elems())
6467       Record.AddStmt(E);
6468   }
6469 }
6470
6471 void OMPClauseWriter::VisitOMPTaskReductionClause(OMPTaskReductionClause *C) {
6472   Record.push_back(C->varlist_size());
6473   VisitOMPClauseWithPostUpdate(C);
6474   Record.AddSourceLocation(C->getLParenLoc());
6475   Record.AddSourceLocation(C->getColonLoc());
6476   Record.AddNestedNameSpecifierLoc(C->getQualifierLoc());
6477   Record.AddDeclarationNameInfo(C->getNameInfo());
6478   for (auto *VE : C->varlists())
6479     Record.AddStmt(VE);
6480   for (auto *VE : C->privates())
6481     Record.AddStmt(VE);
6482   for (auto *E : C->lhs_exprs())
6483     Record.AddStmt(E);
6484   for (auto *E : C->rhs_exprs())
6485     Record.AddStmt(E);
6486   for (auto *E : C->reduction_ops())
6487     Record.AddStmt(E);
6488 }
6489
6490 void OMPClauseWriter::VisitOMPInReductionClause(OMPInReductionClause *C) {
6491   Record.push_back(C->varlist_size());
6492   VisitOMPClauseWithPostUpdate(C);
6493   Record.AddSourceLocation(C->getLParenLoc());
6494   Record.AddSourceLocation(C->getColonLoc());
6495   Record.AddNestedNameSpecifierLoc(C->getQualifierLoc());
6496   Record.AddDeclarationNameInfo(C->getNameInfo());
6497   for (auto *VE : C->varlists())
6498     Record.AddStmt(VE);
6499   for (auto *VE : C->privates())
6500     Record.AddStmt(VE);
6501   for (auto *E : C->lhs_exprs())
6502     Record.AddStmt(E);
6503   for (auto *E : C->rhs_exprs())
6504     Record.AddStmt(E);
6505   for (auto *E : C->reduction_ops())
6506     Record.AddStmt(E);
6507   for (auto *E : C->taskgroup_descriptors())
6508     Record.AddStmt(E);
6509 }
6510
6511 void OMPClauseWriter::VisitOMPLinearClause(OMPLinearClause *C) {
6512   Record.push_back(C->varlist_size());
6513   VisitOMPClauseWithPostUpdate(C);
6514   Record.AddSourceLocation(C->getLParenLoc());
6515   Record.AddSourceLocation(C->getColonLoc());
6516   Record.push_back(C->getModifier());
6517   Record.AddSourceLocation(C->getModifierLoc());
6518   for (auto *VE : C->varlists()) {
6519     Record.AddStmt(VE);
6520   }
6521   for (auto *VE : C->privates()) {
6522     Record.AddStmt(VE);
6523   }
6524   for (auto *VE : C->inits()) {
6525     Record.AddStmt(VE);
6526   }
6527   for (auto *VE : C->updates()) {
6528     Record.AddStmt(VE);
6529   }
6530   for (auto *VE : C->finals()) {
6531     Record.AddStmt(VE);
6532   }
6533   Record.AddStmt(C->getStep());
6534   Record.AddStmt(C->getCalcStep());
6535   for (auto *VE : C->used_expressions())
6536     Record.AddStmt(VE);
6537 }
6538
6539 void OMPClauseWriter::VisitOMPAlignedClause(OMPAlignedClause *C) {
6540   Record.push_back(C->varlist_size());
6541   Record.AddSourceLocation(C->getLParenLoc());
6542   Record.AddSourceLocation(C->getColonLoc());
6543   for (auto *VE : C->varlists())
6544     Record.AddStmt(VE);
6545   Record.AddStmt(C->getAlignment());
6546 }
6547
6548 void OMPClauseWriter::VisitOMPCopyinClause(OMPCopyinClause *C) {
6549   Record.push_back(C->varlist_size());
6550   Record.AddSourceLocation(C->getLParenLoc());
6551   for (auto *VE : C->varlists())
6552     Record.AddStmt(VE);
6553   for (auto *E : C->source_exprs())
6554     Record.AddStmt(E);
6555   for (auto *E : C->destination_exprs())
6556     Record.AddStmt(E);
6557   for (auto *E : C->assignment_ops())
6558     Record.AddStmt(E);
6559 }
6560
6561 void OMPClauseWriter::VisitOMPCopyprivateClause(OMPCopyprivateClause *C) {
6562   Record.push_back(C->varlist_size());
6563   Record.AddSourceLocation(C->getLParenLoc());
6564   for (auto *VE : C->varlists())
6565     Record.AddStmt(VE);
6566   for (auto *E : C->source_exprs())
6567     Record.AddStmt(E);
6568   for (auto *E : C->destination_exprs())
6569     Record.AddStmt(E);
6570   for (auto *E : C->assignment_ops())
6571     Record.AddStmt(E);
6572 }
6573
6574 void OMPClauseWriter::VisitOMPFlushClause(OMPFlushClause *C) {
6575   Record.push_back(C->varlist_size());
6576   Record.AddSourceLocation(C->getLParenLoc());
6577   for (auto *VE : C->varlists())
6578     Record.AddStmt(VE);
6579 }
6580
6581 void OMPClauseWriter::VisitOMPDepobjClause(OMPDepobjClause *C) {
6582   Record.AddStmt(C->getDepobj());
6583   Record.AddSourceLocation(C->getLParenLoc());
6584 }
6585
6586 void OMPClauseWriter::VisitOMPDependClause(OMPDependClause *C) {
6587   Record.push_back(C->varlist_size());
6588   Record.push_back(C->getNumLoops());
6589   Record.AddSourceLocation(C->getLParenLoc());
6590   Record.AddStmt(C->getModifier());
6591   Record.push_back(C->getDependencyKind());
6592   Record.AddSourceLocation(C->getDependencyLoc());
6593   Record.AddSourceLocation(C->getColonLoc());
6594   Record.AddSourceLocation(C->getOmpAllMemoryLoc());
6595   for (auto *VE : C->varlists())
6596     Record.AddStmt(VE);
6597   for (unsigned I = 0, E = C->getNumLoops(); I < E; ++I)
6598     Record.AddStmt(C->getLoopData(I));
6599 }
6600
6601 void OMPClauseWriter::VisitOMPDeviceClause(OMPDeviceClause *C) {
6602   VisitOMPClauseWithPreInit(C);
6603   Record.writeEnum(C->getModifier());
6604   Record.AddStmt(C->getDevice());
6605   Record.AddSourceLocation(C->getModifierLoc());
6606   Record.AddSourceLocation(C->getLParenLoc());
6607 }
6608
6609 void OMPClauseWriter::VisitOMPMapClause(OMPMapClause *C) {
6610   Record.push_back(C->varlist_size());
6611   Record.push_back(C->getUniqueDeclarationsNum());
6612   Record.push_back(C->getTotalComponentListNum());
6613   Record.push_back(C->getTotalComponentsNum());
6614   Record.AddSourceLocation(C->getLParenLoc());
6615   for (unsigned I = 0; I < NumberOfOMPMapClauseModifiers; ++I) {
6616     Record.push_back(C->getMapTypeModifier(I));
6617     Record.AddSourceLocation(C->getMapTypeModifierLoc(I));
6618   }
6619   Record.AddNestedNameSpecifierLoc(C->getMapperQualifierLoc());
6620   Record.AddDeclarationNameInfo(C->getMapperIdInfo());
6621   Record.push_back(C->getMapType());
6622   Record.AddSourceLocation(C->getMapLoc());
6623   Record.AddSourceLocation(C->getColonLoc());
6624   for (auto *E : C->varlists())
6625     Record.AddStmt(E);
6626   for (auto *E : C->mapperlists())
6627     Record.AddStmt(E);
6628   for (auto *D : C->all_decls())
6629     Record.AddDeclRef(D);
6630   for (auto N : C->all_num_lists())
6631     Record.push_back(N);
6632   for (auto N : C->all_lists_sizes())
6633     Record.push_back(N);
6634   for (auto &M : C->all_components()) {
6635     Record.AddStmt(M.getAssociatedExpression());
6636     Record.AddDeclRef(M.getAssociatedDeclaration());
6637   }
6638 }
6639
6640 void OMPClauseWriter::VisitOMPAllocateClause(OMPAllocateClause *C) {
6641   Record.push_back(C->varlist_size());
6642   Record.AddSourceLocation(C->getLParenLoc());
6643   Record.AddSourceLocation(C->getColonLoc());
6644   Record.AddStmt(C->getAllocator());
6645   for (auto *VE : C->varlists())
6646     Record.AddStmt(VE);
6647 }
6648
6649 void OMPClauseWriter::VisitOMPNumTeamsClause(OMPNumTeamsClause *C) {
6650   VisitOMPClauseWithPreInit(C);
6651   Record.AddStmt(C->getNumTeams());
6652   Record.AddSourceLocation(C->getLParenLoc());
6653 }
6654
6655 void OMPClauseWriter::VisitOMPThreadLimitClause(OMPThreadLimitClause *C) {
6656   VisitOMPClauseWithPreInit(C);
6657   Record.AddStmt(C->getThreadLimit());
6658   Record.AddSourceLocation(C->getLParenLoc());
6659 }
6660
6661 void OMPClauseWriter::VisitOMPPriorityClause(OMPPriorityClause *C) {
6662   VisitOMPClauseWithPreInit(C);
6663   Record.AddStmt(C->getPriority());
6664   Record.AddSourceLocation(C->getLParenLoc());
6665 }
6666
6667 void OMPClauseWriter::VisitOMPGrainsizeClause(OMPGrainsizeClause *C) {
6668   VisitOMPClauseWithPreInit(C);
6669   Record.AddStmt(C->getGrainsize());
6670   Record.AddSourceLocation(C->getLParenLoc());
6671 }
6672
6673 void OMPClauseWriter::VisitOMPNumTasksClause(OMPNumTasksClause *C) {
6674   VisitOMPClauseWithPreInit(C);
6675   Record.AddStmt(C->getNumTasks());
6676   Record.AddSourceLocation(C->getLParenLoc());
6677 }
6678
6679 void OMPClauseWriter::VisitOMPHintClause(OMPHintClause *C) {
6680   Record.AddStmt(C->getHint());
6681   Record.AddSourceLocation(C->getLParenLoc());
6682 }
6683
6684 void OMPClauseWriter::VisitOMPDistScheduleClause(OMPDistScheduleClause *C) {
6685   VisitOMPClauseWithPreInit(C);
6686   Record.push_back(C->getDistScheduleKind());
6687   Record.AddStmt(C->getChunkSize());
6688   Record.AddSourceLocation(C->getLParenLoc());
6689   Record.AddSourceLocation(C->getDistScheduleKindLoc());
6690   Record.AddSourceLocation(C->getCommaLoc());
6691 }
6692
6693 void OMPClauseWriter::VisitOMPDefaultmapClause(OMPDefaultmapClause *C) {
6694   Record.push_back(C->getDefaultmapKind());
6695   Record.push_back(C->getDefaultmapModifier());
6696   Record.AddSourceLocation(C->getLParenLoc());
6697   Record.AddSourceLocation(C->getDefaultmapModifierLoc());
6698   Record.AddSourceLocation(C->getDefaultmapKindLoc());
6699 }
6700
6701 void OMPClauseWriter::VisitOMPToClause(OMPToClause *C) {
6702   Record.push_back(C->varlist_size());
6703   Record.push_back(C->getUniqueDeclarationsNum());
6704   Record.push_back(C->getTotalComponentListNum());
6705   Record.push_back(C->getTotalComponentsNum());
6706   Record.AddSourceLocation(C->getLParenLoc());
6707   for (unsigned I = 0; I < NumberOfOMPMotionModifiers; ++I) {
6708     Record.push_back(C->getMotionModifier(I));
6709     Record.AddSourceLocation(C->getMotionModifierLoc(I));
6710   }
6711   Record.AddNestedNameSpecifierLoc(C->getMapperQualifierLoc());
6712   Record.AddDeclarationNameInfo(C->getMapperIdInfo());
6713   Record.AddSourceLocation(C->getColonLoc());
6714   for (auto *E : C->varlists())
6715     Record.AddStmt(E);
6716   for (auto *E : C->mapperlists())
6717     Record.AddStmt(E);
6718   for (auto *D : C->all_decls())
6719     Record.AddDeclRef(D);
6720   for (auto N : C->all_num_lists())
6721     Record.push_back(N);
6722   for (auto N : C->all_lists_sizes())
6723     Record.push_back(N);
6724   for (auto &M : C->all_components()) {
6725     Record.AddStmt(M.getAssociatedExpression());
6726     Record.writeBool(M.isNonContiguous());
6727     Record.AddDeclRef(M.getAssociatedDeclaration());
6728   }
6729 }
6730
6731 void OMPClauseWriter::VisitOMPFromClause(OMPFromClause *C) {
6732   Record.push_back(C->varlist_size());
6733   Record.push_back(C->getUniqueDeclarationsNum());
6734   Record.push_back(C->getTotalComponentListNum());
6735   Record.push_back(C->getTotalComponentsNum());
6736   Record.AddSourceLocation(C->getLParenLoc());
6737   for (unsigned I = 0; I < NumberOfOMPMotionModifiers; ++I) {
6738     Record.push_back(C->getMotionModifier(I));
6739     Record.AddSourceLocation(C->getMotionModifierLoc(I));
6740   }
6741   Record.AddNestedNameSpecifierLoc(C->getMapperQualifierLoc());
6742   Record.AddDeclarationNameInfo(C->getMapperIdInfo());
6743   Record.AddSourceLocation(C->getColonLoc());
6744   for (auto *E : C->varlists())
6745     Record.AddStmt(E);
6746   for (auto *E : C->mapperlists())
6747     Record.AddStmt(E);
6748   for (auto *D : C->all_decls())
6749     Record.AddDeclRef(D);
6750   for (auto N : C->all_num_lists())
6751     Record.push_back(N);
6752   for (auto N : C->all_lists_sizes())
6753     Record.push_back(N);
6754   for (auto &M : C->all_components()) {
6755     Record.AddStmt(M.getAssociatedExpression());
6756     Record.writeBool(M.isNonContiguous());
6757     Record.AddDeclRef(M.getAssociatedDeclaration());
6758   }
6759 }
6760
6761 void OMPClauseWriter::VisitOMPUseDevicePtrClause(OMPUseDevicePtrClause *C) {
6762   Record.push_back(C->varlist_size());
6763   Record.push_back(C->getUniqueDeclarationsNum());
6764   Record.push_back(C->getTotalComponentListNum());
6765   Record.push_back(C->getTotalComponentsNum());
6766   Record.AddSourceLocation(C->getLParenLoc());
6767   for (auto *E : C->varlists())
6768     Record.AddStmt(E);
6769   for (auto *VE : C->private_copies())
6770     Record.AddStmt(VE);
6771   for (auto *VE : C->inits())
6772     Record.AddStmt(VE);
6773   for (auto *D : C->all_decls())
6774     Record.AddDeclRef(D);
6775   for (auto N : C->all_num_lists())
6776     Record.push_back(N);
6777   for (auto N : C->all_lists_sizes())
6778     Record.push_back(N);
6779   for (auto &M : C->all_components()) {
6780     Record.AddStmt(M.getAssociatedExpression());
6781     Record.AddDeclRef(M.getAssociatedDeclaration());
6782   }
6783 }
6784
6785 void OMPClauseWriter::VisitOMPUseDeviceAddrClause(OMPUseDeviceAddrClause *C) {
6786   Record.push_back(C->varlist_size());
6787   Record.push_back(C->getUniqueDeclarationsNum());
6788   Record.push_back(C->getTotalComponentListNum());
6789   Record.push_back(C->getTotalComponentsNum());
6790   Record.AddSourceLocation(C->getLParenLoc());
6791   for (auto *E : C->varlists())
6792     Record.AddStmt(E);
6793   for (auto *D : C->all_decls())
6794     Record.AddDeclRef(D);
6795   for (auto N : C->all_num_lists())
6796     Record.push_back(N);
6797   for (auto N : C->all_lists_sizes())
6798     Record.push_back(N);
6799   for (auto &M : C->all_components()) {
6800     Record.AddStmt(M.getAssociatedExpression());
6801     Record.AddDeclRef(M.getAssociatedDeclaration());
6802   }
6803 }
6804
6805 void OMPClauseWriter::VisitOMPIsDevicePtrClause(OMPIsDevicePtrClause *C) {
6806   Record.push_back(C->varlist_size());
6807   Record.push_back(C->getUniqueDeclarationsNum());
6808   Record.push_back(C->getTotalComponentListNum());
6809   Record.push_back(C->getTotalComponentsNum());
6810   Record.AddSourceLocation(C->getLParenLoc());
6811   for (auto *E : C->varlists())
6812     Record.AddStmt(E);
6813   for (auto *D : C->all_decls())
6814     Record.AddDeclRef(D);
6815   for (auto N : C->all_num_lists())
6816     Record.push_back(N);
6817   for (auto N : C->all_lists_sizes())
6818     Record.push_back(N);
6819   for (auto &M : C->all_components()) {
6820     Record.AddStmt(M.getAssociatedExpression());
6821     Record.AddDeclRef(M.getAssociatedDeclaration());
6822   }
6823 }
6824
6825 void OMPClauseWriter::VisitOMPHasDeviceAddrClause(OMPHasDeviceAddrClause *C) {
6826   Record.push_back(C->varlist_size());
6827   Record.push_back(C->getUniqueDeclarationsNum());
6828   Record.push_back(C->getTotalComponentListNum());
6829   Record.push_back(C->getTotalComponentsNum());
6830   Record.AddSourceLocation(C->getLParenLoc());
6831   for (auto *E : C->varlists())
6832     Record.AddStmt(E);
6833   for (auto *D : C->all_decls())
6834     Record.AddDeclRef(D);
6835   for (auto N : C->all_num_lists())
6836     Record.push_back(N);
6837   for (auto N : C->all_lists_sizes())
6838     Record.push_back(N);
6839   for (auto &M : C->all_components()) {
6840     Record.AddStmt(M.getAssociatedExpression());
6841     Record.AddDeclRef(M.getAssociatedDeclaration());
6842   }
6843 }
6844
6845 void OMPClauseWriter::VisitOMPUnifiedAddressClause(OMPUnifiedAddressClause *) {}
6846
6847 void OMPClauseWriter::VisitOMPUnifiedSharedMemoryClause(
6848     OMPUnifiedSharedMemoryClause *) {}
6849
6850 void OMPClauseWriter::VisitOMPReverseOffloadClause(OMPReverseOffloadClause *) {}
6851
6852 void
6853 OMPClauseWriter::VisitOMPDynamicAllocatorsClause(OMPDynamicAllocatorsClause *) {
6854 }
6855
6856 void OMPClauseWriter::VisitOMPAtomicDefaultMemOrderClause(
6857     OMPAtomicDefaultMemOrderClause *C) {
6858   Record.push_back(C->getAtomicDefaultMemOrderKind());
6859   Record.AddSourceLocation(C->getLParenLoc());
6860   Record.AddSourceLocation(C->getAtomicDefaultMemOrderKindKwLoc());
6861 }
6862
6863 void OMPClauseWriter::VisitOMPNontemporalClause(OMPNontemporalClause *C) {
6864   Record.push_back(C->varlist_size());
6865   Record.AddSourceLocation(C->getLParenLoc());
6866   for (auto *VE : C->varlists())
6867     Record.AddStmt(VE);
6868   for (auto *E : C->private_refs())
6869     Record.AddStmt(E);
6870 }
6871
6872 void OMPClauseWriter::VisitOMPInclusiveClause(OMPInclusiveClause *C) {
6873   Record.push_back(C->varlist_size());
6874   Record.AddSourceLocation(C->getLParenLoc());
6875   for (auto *VE : C->varlists())
6876     Record.AddStmt(VE);
6877 }
6878
6879 void OMPClauseWriter::VisitOMPExclusiveClause(OMPExclusiveClause *C) {
6880   Record.push_back(C->varlist_size());
6881   Record.AddSourceLocation(C->getLParenLoc());
6882   for (auto *VE : C->varlists())
6883     Record.AddStmt(VE);
6884 }
6885
6886 void OMPClauseWriter::VisitOMPOrderClause(OMPOrderClause *C) {
6887   Record.writeEnum(C->getKind());
6888   Record.AddSourceLocation(C->getLParenLoc());
6889   Record.AddSourceLocation(C->getKindKwLoc());
6890 }
6891
6892 void OMPClauseWriter::VisitOMPUsesAllocatorsClause(OMPUsesAllocatorsClause *C) {
6893   Record.push_back(C->getNumberOfAllocators());
6894   Record.AddSourceLocation(C->getLParenLoc());
6895   for (unsigned I = 0, E = C->getNumberOfAllocators(); I < E; ++I) {
6896     OMPUsesAllocatorsClause::Data Data = C->getAllocatorData(I);
6897     Record.AddStmt(Data.Allocator);
6898     Record.AddStmt(Data.AllocatorTraits);
6899     Record.AddSourceLocation(Data.LParenLoc);
6900     Record.AddSourceLocation(Data.RParenLoc);
6901   }
6902 }
6903
6904 void OMPClauseWriter::VisitOMPAffinityClause(OMPAffinityClause *C) {
6905   Record.push_back(C->varlist_size());
6906   Record.AddSourceLocation(C->getLParenLoc());
6907   Record.AddStmt(C->getModifier());
6908   Record.AddSourceLocation(C->getColonLoc());
6909   for (Expr *E : C->varlists())
6910     Record.AddStmt(E);
6911 }
6912
6913 void OMPClauseWriter::VisitOMPBindClause(OMPBindClause *C) {
6914   Record.writeEnum(C->getBindKind());
6915   Record.AddSourceLocation(C->getLParenLoc());
6916   Record.AddSourceLocation(C->getBindKindLoc());
6917 }
6918
6919 void ASTRecordWriter::writeOMPTraitInfo(const OMPTraitInfo *TI) {
6920   writeUInt32(TI->Sets.size());
6921   for (const auto &Set : TI->Sets) {
6922     writeEnum(Set.Kind);
6923     writeUInt32(Set.Selectors.size());
6924     for (const auto &Selector : Set.Selectors) {
6925       writeEnum(Selector.Kind);
6926       writeBool(Selector.ScoreOrCondition);
6927       if (Selector.ScoreOrCondition)
6928         writeExprRef(Selector.ScoreOrCondition);
6929       writeUInt32(Selector.Properties.size());
6930       for (const auto &Property : Selector.Properties)
6931         writeEnum(Property.Kind);
6932     }
6933   }
6934 }
6935
6936 void ASTRecordWriter::writeOMPChildren(OMPChildren *Data) {
6937   if (!Data)
6938     return;
6939   writeUInt32(Data->getNumClauses());
6940   writeUInt32(Data->getNumChildren());
6941   writeBool(Data->hasAssociatedStmt());
6942   for (unsigned I = 0, E = Data->getNumClauses(); I < E; ++I)
6943     writeOMPClause(Data->getClauses()[I]);
6944   if (Data->hasAssociatedStmt())
6945     AddStmt(Data->getAssociatedStmt());
6946   for (unsigned I = 0, E = Data->getNumChildren(); I < E; ++I)
6947     AddStmt(Data->getChildren()[I]);
6948 }