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