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 "clang/Serialization/ASTWriter.h"
14 #include "ASTCommon.h"
15 #include "ASTReaderInternals.h"
16 #include "MultiOnDiskHashTable.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/ASTUnresolvedSet.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/RawCommentList.h"
33 #include "clang/AST/TemplateName.h"
34 #include "clang/AST/Type.h"
35 #include "clang/AST/TypeLocVisitor.h"
36 #include "clang/Basic/Diagnostic.h"
37 #include "clang/Basic/DiagnosticOptions.h"
38 #include "clang/Basic/FileManager.h"
39 #include "clang/Basic/FileSystemOptions.h"
40 #include "clang/Basic/IdentifierTable.h"
41 #include "clang/Basic/LLVM.h"
42 #include "clang/Basic/Lambda.h"
43 #include "clang/Basic/LangOptions.h"
44 #include "clang/Basic/Module.h"
45 #include "clang/Basic/ObjCRuntime.h"
46 #include "clang/Basic/OpenCLOptions.h"
47 #include "clang/Basic/SourceLocation.h"
48 #include "clang/Basic/SourceManager.h"
49 #include "clang/Basic/SourceManagerInternals.h"
50 #include "clang/Basic/Specifiers.h"
51 #include "clang/Basic/TargetInfo.h"
52 #include "clang/Basic/TargetOptions.h"
53 #include "clang/Basic/Version.h"
54 #include "clang/Lex/HeaderSearch.h"
55 #include "clang/Lex/HeaderSearchOptions.h"
56 #include "clang/Lex/MacroInfo.h"
57 #include "clang/Lex/ModuleMap.h"
58 #include "clang/Lex/PreprocessingRecord.h"
59 #include "clang/Lex/Preprocessor.h"
60 #include "clang/Lex/PreprocessorOptions.h"
61 #include "clang/Lex/Token.h"
62 #include "clang/Sema/IdentifierResolver.h"
63 #include "clang/Sema/ObjCMethodList.h"
64 #include "clang/Sema/Sema.h"
65 #include "clang/Sema/Weak.h"
66 #include "clang/Serialization/ASTReader.h"
67 #include "clang/Serialization/InMemoryModuleCache.h"
68 #include "clang/Serialization/Module.h"
69 #include "clang/Serialization/ModuleFileExtension.h"
70 #include "clang/Serialization/SerializationDiagnostic.h"
71 #include "llvm/ADT/APFloat.h"
72 #include "llvm/ADT/APInt.h"
73 #include "llvm/ADT/APSInt.h"
74 #include "llvm/ADT/ArrayRef.h"
75 #include "llvm/ADT/DenseMap.h"
76 #include "llvm/ADT/Hashing.h"
77 #include "llvm/ADT/Optional.h"
78 #include "llvm/ADT/PointerIntPair.h"
79 #include "llvm/ADT/STLExtras.h"
80 #include "llvm/ADT/ScopeExit.h"
81 #include "llvm/ADT/SmallSet.h"
82 #include "llvm/ADT/SmallString.h"
83 #include "llvm/ADT/SmallVector.h"
84 #include "llvm/ADT/StringMap.h"
85 #include "llvm/ADT/StringRef.h"
86 #include "llvm/Bitstream/BitCodes.h"
87 #include "llvm/Bitstream/BitstreamWriter.h"
88 #include "llvm/Support/Casting.h"
89 #include "llvm/Support/Compression.h"
90 #include "llvm/Support/DJB.h"
91 #include "llvm/Support/Endian.h"
92 #include "llvm/Support/EndianStream.h"
93 #include "llvm/Support/Error.h"
94 #include "llvm/Support/ErrorHandling.h"
95 #include "llvm/Support/MemoryBuffer.h"
96 #include "llvm/Support/OnDiskHashTable.h"
97 #include "llvm/Support/Path.h"
98 #include "llvm/Support/SHA1.h"
99 #include "llvm/Support/VersionTuple.h"
100 #include "llvm/Support/raw_ostream.h"
101 #include <algorithm>
102 #include <cassert>
103 #include <cstdint>
104 #include <cstdlib>
105 #include <cstring>
106 #include <ctime>
107 #include <deque>
108 #include <limits>
109 #include <memory>
110 #include <queue>
111 #include <tuple>
112 #include <utility>
113 #include <vector>
114 
115 using namespace clang;
116 using namespace clang::serialization;
117 
118 template <typename T, typename Allocator>
119 static StringRef bytes(const std::vector<T, Allocator> &v) {
120   if (v.empty()) return StringRef();
121   return StringRef(reinterpret_cast<const char*>(&v[0]),
122                          sizeof(T) * v.size());
123 }
124 
125 template <typename T>
126 static StringRef bytes(const SmallVectorImpl<T> &v) {
127   return StringRef(reinterpret_cast<const char*>(v.data()),
128                          sizeof(T) * v.size());
129 }
130 
131 //===----------------------------------------------------------------------===//
132 // Type serialization
133 //===----------------------------------------------------------------------===//
134 
135 namespace clang {
136 
137   class ASTTypeWriter {
138     ASTWriter &Writer;
139     ASTRecordWriter Record;
140 
141     /// Type code that corresponds to the record generated.
142     TypeCode Code = static_cast<TypeCode>(0);
143 
144     /// Abbreviation to use for the record, if any.
145     unsigned AbbrevToUse = 0;
146 
147   public:
148     ASTTypeWriter(ASTWriter &Writer, ASTWriter::RecordDataImpl &Record)
149       : Writer(Writer), Record(Writer, Record) {}
150 
151     uint64_t Emit() {
152       return Record.Emit(Code, AbbrevToUse);
153     }
154 
155     void Visit(QualType T) {
156       if (T.hasLocalNonFastQualifiers()) {
157         Qualifiers Qs = T.getLocalQualifiers();
158         Record.AddTypeRef(T.getLocalUnqualifiedType());
159         Record.push_back(Qs.getAsOpaqueValue());
160         Code = TYPE_EXT_QUAL;
161         AbbrevToUse = Writer.TypeExtQualAbbrev;
162       } else {
163         switch (T->getTypeClass()) {
164           // For all of the concrete, non-dependent types, call the
165           // appropriate visitor function.
166 #define TYPE(Class, Base) \
167         case Type::Class: Visit##Class##Type(cast<Class##Type>(T)); break;
168 #define ABSTRACT_TYPE(Class, Base)
169 #include "clang/AST/TypeNodes.inc"
170         }
171       }
172     }
173 
174     void VisitArrayType(const ArrayType *T);
175     void VisitFunctionType(const FunctionType *T);
176     void VisitTagType(const TagType *T);
177 
178 #define TYPE(Class, Base) void Visit##Class##Type(const Class##Type *T);
179 #define ABSTRACT_TYPE(Class, Base)
180 #include "clang/AST/TypeNodes.inc"
181   };
182 
183 } // namespace clang
184 
185 void ASTTypeWriter::VisitBuiltinType(const BuiltinType *T) {
186   llvm_unreachable("Built-in types are never serialized");
187 }
188 
189 void ASTTypeWriter::VisitComplexType(const ComplexType *T) {
190   Record.AddTypeRef(T->getElementType());
191   Code = TYPE_COMPLEX;
192 }
193 
194 void ASTTypeWriter::VisitPointerType(const PointerType *T) {
195   Record.AddTypeRef(T->getPointeeType());
196   Code = TYPE_POINTER;
197 }
198 
199 void ASTTypeWriter::VisitDecayedType(const DecayedType *T) {
200   Record.AddTypeRef(T->getOriginalType());
201   Code = TYPE_DECAYED;
202 }
203 
204 void ASTTypeWriter::VisitAdjustedType(const AdjustedType *T) {
205   Record.AddTypeRef(T->getOriginalType());
206   Record.AddTypeRef(T->getAdjustedType());
207   Code = TYPE_ADJUSTED;
208 }
209 
210 void ASTTypeWriter::VisitBlockPointerType(const BlockPointerType *T) {
211   Record.AddTypeRef(T->getPointeeType());
212   Code = TYPE_BLOCK_POINTER;
213 }
214 
215 void ASTTypeWriter::VisitLValueReferenceType(const LValueReferenceType *T) {
216   Record.AddTypeRef(T->getPointeeTypeAsWritten());
217   Record.push_back(T->isSpelledAsLValue());
218   Code = TYPE_LVALUE_REFERENCE;
219 }
220 
221 void ASTTypeWriter::VisitRValueReferenceType(const RValueReferenceType *T) {
222   Record.AddTypeRef(T->getPointeeTypeAsWritten());
223   Code = TYPE_RVALUE_REFERENCE;
224 }
225 
226 void ASTTypeWriter::VisitMemberPointerType(const MemberPointerType *T) {
227   Record.AddTypeRef(T->getPointeeType());
228   Record.AddTypeRef(QualType(T->getClass(), 0));
229   Code = TYPE_MEMBER_POINTER;
230 }
231 
232 void ASTTypeWriter::VisitArrayType(const ArrayType *T) {
233   Record.AddTypeRef(T->getElementType());
234   Record.push_back(T->getSizeModifier()); // FIXME: stable values
235   Record.push_back(T->getIndexTypeCVRQualifiers()); // FIXME: stable values
236 }
237 
238 void ASTTypeWriter::VisitConstantArrayType(const ConstantArrayType *T) {
239   VisitArrayType(T);
240   Record.AddAPInt(T->getSize());
241   Record.AddStmt(const_cast<Expr*>(T->getSizeExpr()));
242   Code = TYPE_CONSTANT_ARRAY;
243 }
244 
245 void ASTTypeWriter::VisitIncompleteArrayType(const IncompleteArrayType *T) {
246   VisitArrayType(T);
247   Code = TYPE_INCOMPLETE_ARRAY;
248 }
249 
250 void ASTTypeWriter::VisitVariableArrayType(const VariableArrayType *T) {
251   VisitArrayType(T);
252   Record.AddSourceLocation(T->getLBracketLoc());
253   Record.AddSourceLocation(T->getRBracketLoc());
254   Record.AddStmt(T->getSizeExpr());
255   Code = TYPE_VARIABLE_ARRAY;
256 }
257 
258 void ASTTypeWriter::VisitVectorType(const VectorType *T) {
259   Record.AddTypeRef(T->getElementType());
260   Record.push_back(T->getNumElements());
261   Record.push_back(T->getVectorKind());
262   Code = TYPE_VECTOR;
263 }
264 
265 void ASTTypeWriter::VisitExtVectorType(const ExtVectorType *T) {
266   VisitVectorType(T);
267   Code = TYPE_EXT_VECTOR;
268 }
269 
270 void ASTTypeWriter::VisitFunctionType(const FunctionType *T) {
271   Record.AddTypeRef(T->getReturnType());
272   FunctionType::ExtInfo C = T->getExtInfo();
273   Record.push_back(C.getNoReturn());
274   Record.push_back(C.getHasRegParm());
275   Record.push_back(C.getRegParm());
276   // FIXME: need to stabilize encoding of calling convention...
277   Record.push_back(C.getCC());
278   Record.push_back(C.getProducesResult());
279   Record.push_back(C.getNoCallerSavedRegs());
280   Record.push_back(C.getNoCfCheck());
281 
282   if (C.getHasRegParm() || C.getRegParm() || C.getProducesResult())
283     AbbrevToUse = 0;
284 }
285 
286 void ASTTypeWriter::VisitFunctionNoProtoType(const FunctionNoProtoType *T) {
287   VisitFunctionType(T);
288   Code = TYPE_FUNCTION_NO_PROTO;
289 }
290 
291 static void addExceptionSpec(const FunctionProtoType *T,
292                              ASTRecordWriter &Record) {
293   Record.push_back(T->getExceptionSpecType());
294   if (T->getExceptionSpecType() == EST_Dynamic) {
295     Record.push_back(T->getNumExceptions());
296     for (unsigned I = 0, N = T->getNumExceptions(); I != N; ++I)
297       Record.AddTypeRef(T->getExceptionType(I));
298   } else if (isComputedNoexcept(T->getExceptionSpecType())) {
299     Record.AddStmt(T->getNoexceptExpr());
300   } else if (T->getExceptionSpecType() == EST_Uninstantiated) {
301     Record.AddDeclRef(T->getExceptionSpecDecl());
302     Record.AddDeclRef(T->getExceptionSpecTemplate());
303   } else if (T->getExceptionSpecType() == EST_Unevaluated) {
304     Record.AddDeclRef(T->getExceptionSpecDecl());
305   }
306 }
307 
308 void ASTTypeWriter::VisitFunctionProtoType(const FunctionProtoType *T) {
309   VisitFunctionType(T);
310 
311   Record.push_back(T->isVariadic());
312   Record.push_back(T->hasTrailingReturn());
313   Record.push_back(T->getMethodQuals().getAsOpaqueValue());
314   Record.push_back(static_cast<unsigned>(T->getRefQualifier()));
315   addExceptionSpec(T, Record);
316 
317   Record.push_back(T->getNumParams());
318   for (unsigned I = 0, N = T->getNumParams(); I != N; ++I)
319     Record.AddTypeRef(T->getParamType(I));
320 
321   if (T->hasExtParameterInfos()) {
322     for (unsigned I = 0, N = T->getNumParams(); I != N; ++I)
323       Record.push_back(T->getExtParameterInfo(I).getOpaqueValue());
324   }
325 
326   if (T->isVariadic() || T->hasTrailingReturn() || T->getMethodQuals() ||
327       T->getRefQualifier() || T->getExceptionSpecType() != EST_None ||
328       T->hasExtParameterInfos())
329     AbbrevToUse = 0;
330 
331   Code = TYPE_FUNCTION_PROTO;
332 }
333 
334 void ASTTypeWriter::VisitUnresolvedUsingType(const UnresolvedUsingType *T) {
335   Record.AddDeclRef(T->getDecl());
336   Code = TYPE_UNRESOLVED_USING;
337 }
338 
339 void ASTTypeWriter::VisitTypedefType(const TypedefType *T) {
340   Record.AddDeclRef(T->getDecl());
341   assert(!T->isCanonicalUnqualified() && "Invalid typedef ?");
342   Record.AddTypeRef(T->getCanonicalTypeInternal());
343   Code = TYPE_TYPEDEF;
344 }
345 
346 void ASTTypeWriter::VisitTypeOfExprType(const TypeOfExprType *T) {
347   Record.AddStmt(T->getUnderlyingExpr());
348   Code = TYPE_TYPEOF_EXPR;
349 }
350 
351 void ASTTypeWriter::VisitTypeOfType(const TypeOfType *T) {
352   Record.AddTypeRef(T->getUnderlyingType());
353   Code = TYPE_TYPEOF;
354 }
355 
356 void ASTTypeWriter::VisitDecltypeType(const DecltypeType *T) {
357   Record.AddTypeRef(T->getUnderlyingType());
358   Record.AddStmt(T->getUnderlyingExpr());
359   Code = TYPE_DECLTYPE;
360 }
361 
362 void ASTTypeWriter::VisitUnaryTransformType(const UnaryTransformType *T) {
363   Record.AddTypeRef(T->getBaseType());
364   Record.AddTypeRef(T->getUnderlyingType());
365   Record.push_back(T->getUTTKind());
366   Code = TYPE_UNARY_TRANSFORM;
367 }
368 
369 void ASTTypeWriter::VisitAutoType(const AutoType *T) {
370   Record.AddTypeRef(T->getDeducedType());
371   Record.push_back((unsigned)T->getKeyword());
372   if (T->getDeducedType().isNull())
373     Record.push_back(T->containsUnexpandedParameterPack() ? 2 :
374                      T->isDependentType() ? 1 : 0);
375   Code = TYPE_AUTO;
376 }
377 
378 void ASTTypeWriter::VisitDeducedTemplateSpecializationType(
379     const DeducedTemplateSpecializationType *T) {
380   Record.AddTemplateName(T->getTemplateName());
381   Record.AddTypeRef(T->getDeducedType());
382   if (T->getDeducedType().isNull())
383     Record.push_back(T->isDependentType());
384   Code = TYPE_DEDUCED_TEMPLATE_SPECIALIZATION;
385 }
386 
387 void ASTTypeWriter::VisitTagType(const TagType *T) {
388   Record.push_back(T->isDependentType());
389   Record.AddDeclRef(T->getDecl()->getCanonicalDecl());
390   assert(!T->isBeingDefined() &&
391          "Cannot serialize in the middle of a type definition");
392 }
393 
394 void ASTTypeWriter::VisitRecordType(const RecordType *T) {
395   VisitTagType(T);
396   Code = TYPE_RECORD;
397 }
398 
399 void ASTTypeWriter::VisitEnumType(const EnumType *T) {
400   VisitTagType(T);
401   Code = TYPE_ENUM;
402 }
403 
404 void ASTTypeWriter::VisitAttributedType(const AttributedType *T) {
405   Record.AddTypeRef(T->getModifiedType());
406   Record.AddTypeRef(T->getEquivalentType());
407   Record.push_back(T->getAttrKind());
408   Code = TYPE_ATTRIBUTED;
409 }
410 
411 void
412 ASTTypeWriter::VisitSubstTemplateTypeParmType(
413                                         const SubstTemplateTypeParmType *T) {
414   Record.AddTypeRef(QualType(T->getReplacedParameter(), 0));
415   Record.AddTypeRef(T->getReplacementType());
416   Code = TYPE_SUBST_TEMPLATE_TYPE_PARM;
417 }
418 
419 void
420 ASTTypeWriter::VisitSubstTemplateTypeParmPackType(
421                                       const SubstTemplateTypeParmPackType *T) {
422   Record.AddTypeRef(QualType(T->getReplacedParameter(), 0));
423   Record.AddTemplateArgument(T->getArgumentPack());
424   Code = TYPE_SUBST_TEMPLATE_TYPE_PARM_PACK;
425 }
426 
427 void
428 ASTTypeWriter::VisitTemplateSpecializationType(
429                                        const TemplateSpecializationType *T) {
430   Record.push_back(T->isDependentType());
431   Record.AddTemplateName(T->getTemplateName());
432   Record.push_back(T->getNumArgs());
433   for (const auto &ArgI : *T)
434     Record.AddTemplateArgument(ArgI);
435   Record.AddTypeRef(T->isTypeAlias() ? T->getAliasedType()
436                                      : T->isCanonicalUnqualified()
437                                            ? QualType()
438                                            : T->getCanonicalTypeInternal());
439   Code = TYPE_TEMPLATE_SPECIALIZATION;
440 }
441 
442 void
443 ASTTypeWriter::VisitDependentSizedArrayType(const DependentSizedArrayType *T) {
444   VisitArrayType(T);
445   Record.AddStmt(T->getSizeExpr());
446   Record.AddSourceRange(T->getBracketsRange());
447   Code = TYPE_DEPENDENT_SIZED_ARRAY;
448 }
449 
450 void
451 ASTTypeWriter::VisitDependentSizedExtVectorType(
452                                         const DependentSizedExtVectorType *T) {
453   Record.AddTypeRef(T->getElementType());
454   Record.AddStmt(T->getSizeExpr());
455   Record.AddSourceLocation(T->getAttributeLoc());
456   Code = TYPE_DEPENDENT_SIZED_EXT_VECTOR;
457 }
458 
459 void ASTTypeWriter::VisitDependentVectorType(const DependentVectorType *T) {
460   Record.AddTypeRef(T->getElementType());
461   Record.AddStmt(const_cast<Expr*>(T->getSizeExpr()));
462   Record.AddSourceLocation(T->getAttributeLoc());
463   Record.push_back(T->getVectorKind());
464   Code = TYPE_DEPENDENT_SIZED_VECTOR;
465 }
466 
467 void
468 ASTTypeWriter::VisitDependentAddressSpaceType(
469     const DependentAddressSpaceType *T) {
470   Record.AddTypeRef(T->getPointeeType());
471   Record.AddStmt(T->getAddrSpaceExpr());
472   Record.AddSourceLocation(T->getAttributeLoc());
473   Code = TYPE_DEPENDENT_ADDRESS_SPACE;
474 }
475 
476 void
477 ASTTypeWriter::VisitTemplateTypeParmType(const TemplateTypeParmType *T) {
478   Record.push_back(T->getDepth());
479   Record.push_back(T->getIndex());
480   Record.push_back(T->isParameterPack());
481   Record.AddDeclRef(T->getDecl());
482   Code = TYPE_TEMPLATE_TYPE_PARM;
483 }
484 
485 void
486 ASTTypeWriter::VisitDependentNameType(const DependentNameType *T) {
487   Record.push_back(T->getKeyword());
488   Record.AddNestedNameSpecifier(T->getQualifier());
489   Record.AddIdentifierRef(T->getIdentifier());
490   Record.AddTypeRef(
491       T->isCanonicalUnqualified() ? QualType() : T->getCanonicalTypeInternal());
492   Code = TYPE_DEPENDENT_NAME;
493 }
494 
495 void
496 ASTTypeWriter::VisitDependentTemplateSpecializationType(
497                                 const DependentTemplateSpecializationType *T) {
498   Record.push_back(T->getKeyword());
499   Record.AddNestedNameSpecifier(T->getQualifier());
500   Record.AddIdentifierRef(T->getIdentifier());
501   Record.push_back(T->getNumArgs());
502   for (const auto &I : *T)
503     Record.AddTemplateArgument(I);
504   Code = TYPE_DEPENDENT_TEMPLATE_SPECIALIZATION;
505 }
506 
507 void ASTTypeWriter::VisitPackExpansionType(const PackExpansionType *T) {
508   Record.AddTypeRef(T->getPattern());
509   if (Optional<unsigned> NumExpansions = T->getNumExpansions())
510     Record.push_back(*NumExpansions + 1);
511   else
512     Record.push_back(0);
513   Code = TYPE_PACK_EXPANSION;
514 }
515 
516 void ASTTypeWriter::VisitParenType(const ParenType *T) {
517   Record.AddTypeRef(T->getInnerType());
518   Code = TYPE_PAREN;
519 }
520 
521 void ASTTypeWriter::VisitMacroQualifiedType(const MacroQualifiedType *T) {
522   Record.AddTypeRef(T->getUnderlyingType());
523   Record.AddIdentifierRef(T->getMacroIdentifier());
524   Code = TYPE_MACRO_QUALIFIED;
525 }
526 
527 void ASTTypeWriter::VisitElaboratedType(const ElaboratedType *T) {
528   Record.push_back(T->getKeyword());
529   Record.AddNestedNameSpecifier(T->getQualifier());
530   Record.AddTypeRef(T->getNamedType());
531   Record.AddDeclRef(T->getOwnedTagDecl());
532   Code = TYPE_ELABORATED;
533 }
534 
535 void ASTTypeWriter::VisitInjectedClassNameType(const InjectedClassNameType *T) {
536   Record.AddDeclRef(T->getDecl()->getCanonicalDecl());
537   Record.AddTypeRef(T->getInjectedSpecializationType());
538   Code = TYPE_INJECTED_CLASS_NAME;
539 }
540 
541 void ASTTypeWriter::VisitObjCInterfaceType(const ObjCInterfaceType *T) {
542   Record.AddDeclRef(T->getDecl()->getCanonicalDecl());
543   Code = TYPE_OBJC_INTERFACE;
544 }
545 
546 void ASTTypeWriter::VisitObjCTypeParamType(const ObjCTypeParamType *T) {
547   Record.AddDeclRef(T->getDecl());
548   Record.push_back(T->getNumProtocols());
549   for (const auto *I : T->quals())
550     Record.AddDeclRef(I);
551   Code = TYPE_OBJC_TYPE_PARAM;
552 }
553 
554 void ASTTypeWriter::VisitObjCObjectType(const ObjCObjectType *T) {
555   Record.AddTypeRef(T->getBaseType());
556   Record.push_back(T->getTypeArgsAsWritten().size());
557   for (auto TypeArg : T->getTypeArgsAsWritten())
558     Record.AddTypeRef(TypeArg);
559   Record.push_back(T->getNumProtocols());
560   for (const auto *I : T->quals())
561     Record.AddDeclRef(I);
562   Record.push_back(T->isKindOfTypeAsWritten());
563   Code = TYPE_OBJC_OBJECT;
564 }
565 
566 void
567 ASTTypeWriter::VisitObjCObjectPointerType(const ObjCObjectPointerType *T) {
568   Record.AddTypeRef(T->getPointeeType());
569   Code = TYPE_OBJC_OBJECT_POINTER;
570 }
571 
572 void
573 ASTTypeWriter::VisitAtomicType(const AtomicType *T) {
574   Record.AddTypeRef(T->getValueType());
575   Code = TYPE_ATOMIC;
576 }
577 
578 void
579 ASTTypeWriter::VisitPipeType(const PipeType *T) {
580   Record.AddTypeRef(T->getElementType());
581   Record.push_back(T->isReadOnly());
582   Code = TYPE_PIPE;
583 }
584 
585 namespace {
586 
587 class TypeLocWriter : public TypeLocVisitor<TypeLocWriter> {
588   ASTRecordWriter &Record;
589 
590 public:
591   TypeLocWriter(ASTRecordWriter &Record) : Record(Record) {}
592 
593 #define ABSTRACT_TYPELOC(CLASS, PARENT)
594 #define TYPELOC(CLASS, PARENT) \
595     void Visit##CLASS##TypeLoc(CLASS##TypeLoc TyLoc);
596 #include "clang/AST/TypeLocNodes.def"
597 
598   void VisitArrayTypeLoc(ArrayTypeLoc TyLoc);
599   void VisitFunctionTypeLoc(FunctionTypeLoc TyLoc);
600 };
601 
602 } // namespace
603 
604 void TypeLocWriter::VisitQualifiedTypeLoc(QualifiedTypeLoc TL) {
605   // nothing to do
606 }
607 
608 void TypeLocWriter::VisitBuiltinTypeLoc(BuiltinTypeLoc TL) {
609   Record.AddSourceLocation(TL.getBuiltinLoc());
610   if (TL.needsExtraLocalData()) {
611     Record.push_back(TL.getWrittenTypeSpec());
612     Record.push_back(TL.getWrittenSignSpec());
613     Record.push_back(TL.getWrittenWidthSpec());
614     Record.push_back(TL.hasModeAttr());
615   }
616 }
617 
618 void TypeLocWriter::VisitComplexTypeLoc(ComplexTypeLoc TL) {
619   Record.AddSourceLocation(TL.getNameLoc());
620 }
621 
622 void TypeLocWriter::VisitPointerTypeLoc(PointerTypeLoc TL) {
623   Record.AddSourceLocation(TL.getStarLoc());
624 }
625 
626 void TypeLocWriter::VisitDecayedTypeLoc(DecayedTypeLoc TL) {
627   // nothing to do
628 }
629 
630 void TypeLocWriter::VisitAdjustedTypeLoc(AdjustedTypeLoc TL) {
631   // nothing to do
632 }
633 
634 void TypeLocWriter::VisitBlockPointerTypeLoc(BlockPointerTypeLoc TL) {
635   Record.AddSourceLocation(TL.getCaretLoc());
636 }
637 
638 void TypeLocWriter::VisitLValueReferenceTypeLoc(LValueReferenceTypeLoc TL) {
639   Record.AddSourceLocation(TL.getAmpLoc());
640 }
641 
642 void TypeLocWriter::VisitRValueReferenceTypeLoc(RValueReferenceTypeLoc TL) {
643   Record.AddSourceLocation(TL.getAmpAmpLoc());
644 }
645 
646 void TypeLocWriter::VisitMemberPointerTypeLoc(MemberPointerTypeLoc TL) {
647   Record.AddSourceLocation(TL.getStarLoc());
648   Record.AddTypeSourceInfo(TL.getClassTInfo());
649 }
650 
651 void TypeLocWriter::VisitArrayTypeLoc(ArrayTypeLoc TL) {
652   Record.AddSourceLocation(TL.getLBracketLoc());
653   Record.AddSourceLocation(TL.getRBracketLoc());
654   Record.push_back(TL.getSizeExpr() ? 1 : 0);
655   if (TL.getSizeExpr())
656     Record.AddStmt(TL.getSizeExpr());
657 }
658 
659 void TypeLocWriter::VisitConstantArrayTypeLoc(ConstantArrayTypeLoc TL) {
660   VisitArrayTypeLoc(TL);
661 }
662 
663 void TypeLocWriter::VisitIncompleteArrayTypeLoc(IncompleteArrayTypeLoc TL) {
664   VisitArrayTypeLoc(TL);
665 }
666 
667 void TypeLocWriter::VisitVariableArrayTypeLoc(VariableArrayTypeLoc TL) {
668   VisitArrayTypeLoc(TL);
669 }
670 
671 void TypeLocWriter::VisitDependentSizedArrayTypeLoc(
672                                             DependentSizedArrayTypeLoc TL) {
673   VisitArrayTypeLoc(TL);
674 }
675 
676 void TypeLocWriter::VisitDependentAddressSpaceTypeLoc(
677     DependentAddressSpaceTypeLoc TL) {
678   Record.AddSourceLocation(TL.getAttrNameLoc());
679   SourceRange range = TL.getAttrOperandParensRange();
680   Record.AddSourceLocation(range.getBegin());
681   Record.AddSourceLocation(range.getEnd());
682   Record.AddStmt(TL.getAttrExprOperand());
683 }
684 
685 void TypeLocWriter::VisitDependentSizedExtVectorTypeLoc(
686                                         DependentSizedExtVectorTypeLoc TL) {
687   Record.AddSourceLocation(TL.getNameLoc());
688 }
689 
690 void TypeLocWriter::VisitVectorTypeLoc(VectorTypeLoc TL) {
691   Record.AddSourceLocation(TL.getNameLoc());
692 }
693 
694 void TypeLocWriter::VisitDependentVectorTypeLoc(
695     DependentVectorTypeLoc TL) {
696   Record.AddSourceLocation(TL.getNameLoc());
697 }
698 
699 void TypeLocWriter::VisitExtVectorTypeLoc(ExtVectorTypeLoc TL) {
700   Record.AddSourceLocation(TL.getNameLoc());
701 }
702 
703 void TypeLocWriter::VisitFunctionTypeLoc(FunctionTypeLoc TL) {
704   Record.AddSourceLocation(TL.getLocalRangeBegin());
705   Record.AddSourceLocation(TL.getLParenLoc());
706   Record.AddSourceLocation(TL.getRParenLoc());
707   Record.AddSourceRange(TL.getExceptionSpecRange());
708   Record.AddSourceLocation(TL.getLocalRangeEnd());
709   for (unsigned i = 0, e = TL.getNumParams(); i != e; ++i)
710     Record.AddDeclRef(TL.getParam(i));
711 }
712 
713 void TypeLocWriter::VisitFunctionProtoTypeLoc(FunctionProtoTypeLoc TL) {
714   VisitFunctionTypeLoc(TL);
715 }
716 
717 void TypeLocWriter::VisitFunctionNoProtoTypeLoc(FunctionNoProtoTypeLoc TL) {
718   VisitFunctionTypeLoc(TL);
719 }
720 
721 void TypeLocWriter::VisitUnresolvedUsingTypeLoc(UnresolvedUsingTypeLoc TL) {
722   Record.AddSourceLocation(TL.getNameLoc());
723 }
724 
725 void TypeLocWriter::VisitTypedefTypeLoc(TypedefTypeLoc TL) {
726   Record.AddSourceLocation(TL.getNameLoc());
727 }
728 
729 void TypeLocWriter::VisitObjCTypeParamTypeLoc(ObjCTypeParamTypeLoc TL) {
730   if (TL.getNumProtocols()) {
731     Record.AddSourceLocation(TL.getProtocolLAngleLoc());
732     Record.AddSourceLocation(TL.getProtocolRAngleLoc());
733   }
734   for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
735     Record.AddSourceLocation(TL.getProtocolLoc(i));
736 }
737 
738 void TypeLocWriter::VisitTypeOfExprTypeLoc(TypeOfExprTypeLoc TL) {
739   Record.AddSourceLocation(TL.getTypeofLoc());
740   Record.AddSourceLocation(TL.getLParenLoc());
741   Record.AddSourceLocation(TL.getRParenLoc());
742 }
743 
744 void TypeLocWriter::VisitTypeOfTypeLoc(TypeOfTypeLoc TL) {
745   Record.AddSourceLocation(TL.getTypeofLoc());
746   Record.AddSourceLocation(TL.getLParenLoc());
747   Record.AddSourceLocation(TL.getRParenLoc());
748   Record.AddTypeSourceInfo(TL.getUnderlyingTInfo());
749 }
750 
751 void TypeLocWriter::VisitDecltypeTypeLoc(DecltypeTypeLoc TL) {
752   Record.AddSourceLocation(TL.getNameLoc());
753 }
754 
755 void TypeLocWriter::VisitUnaryTransformTypeLoc(UnaryTransformTypeLoc TL) {
756   Record.AddSourceLocation(TL.getKWLoc());
757   Record.AddSourceLocation(TL.getLParenLoc());
758   Record.AddSourceLocation(TL.getRParenLoc());
759   Record.AddTypeSourceInfo(TL.getUnderlyingTInfo());
760 }
761 
762 void TypeLocWriter::VisitAutoTypeLoc(AutoTypeLoc TL) {
763   Record.AddSourceLocation(TL.getNameLoc());
764 }
765 
766 void TypeLocWriter::VisitDeducedTemplateSpecializationTypeLoc(
767     DeducedTemplateSpecializationTypeLoc TL) {
768   Record.AddSourceLocation(TL.getTemplateNameLoc());
769 }
770 
771 void TypeLocWriter::VisitRecordTypeLoc(RecordTypeLoc TL) {
772   Record.AddSourceLocation(TL.getNameLoc());
773 }
774 
775 void TypeLocWriter::VisitEnumTypeLoc(EnumTypeLoc TL) {
776   Record.AddSourceLocation(TL.getNameLoc());
777 }
778 
779 void TypeLocWriter::VisitAttributedTypeLoc(AttributedTypeLoc TL) {
780   Record.AddAttr(TL.getAttr());
781 }
782 
783 void TypeLocWriter::VisitTemplateTypeParmTypeLoc(TemplateTypeParmTypeLoc TL) {
784   Record.AddSourceLocation(TL.getNameLoc());
785 }
786 
787 void TypeLocWriter::VisitSubstTemplateTypeParmTypeLoc(
788                                             SubstTemplateTypeParmTypeLoc TL) {
789   Record.AddSourceLocation(TL.getNameLoc());
790 }
791 
792 void TypeLocWriter::VisitSubstTemplateTypeParmPackTypeLoc(
793                                           SubstTemplateTypeParmPackTypeLoc TL) {
794   Record.AddSourceLocation(TL.getNameLoc());
795 }
796 
797 void TypeLocWriter::VisitTemplateSpecializationTypeLoc(
798                                            TemplateSpecializationTypeLoc TL) {
799   Record.AddSourceLocation(TL.getTemplateKeywordLoc());
800   Record.AddSourceLocation(TL.getTemplateNameLoc());
801   Record.AddSourceLocation(TL.getLAngleLoc());
802   Record.AddSourceLocation(TL.getRAngleLoc());
803   for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
804     Record.AddTemplateArgumentLocInfo(TL.getArgLoc(i).getArgument().getKind(),
805                                       TL.getArgLoc(i).getLocInfo());
806 }
807 
808 void TypeLocWriter::VisitParenTypeLoc(ParenTypeLoc TL) {
809   Record.AddSourceLocation(TL.getLParenLoc());
810   Record.AddSourceLocation(TL.getRParenLoc());
811 }
812 
813 void TypeLocWriter::VisitMacroQualifiedTypeLoc(MacroQualifiedTypeLoc TL) {
814   Record.AddSourceLocation(TL.getExpansionLoc());
815 }
816 
817 void TypeLocWriter::VisitElaboratedTypeLoc(ElaboratedTypeLoc TL) {
818   Record.AddSourceLocation(TL.getElaboratedKeywordLoc());
819   Record.AddNestedNameSpecifierLoc(TL.getQualifierLoc());
820 }
821 
822 void TypeLocWriter::VisitInjectedClassNameTypeLoc(InjectedClassNameTypeLoc TL) {
823   Record.AddSourceLocation(TL.getNameLoc());
824 }
825 
826 void TypeLocWriter::VisitDependentNameTypeLoc(DependentNameTypeLoc TL) {
827   Record.AddSourceLocation(TL.getElaboratedKeywordLoc());
828   Record.AddNestedNameSpecifierLoc(TL.getQualifierLoc());
829   Record.AddSourceLocation(TL.getNameLoc());
830 }
831 
832 void TypeLocWriter::VisitDependentTemplateSpecializationTypeLoc(
833        DependentTemplateSpecializationTypeLoc TL) {
834   Record.AddSourceLocation(TL.getElaboratedKeywordLoc());
835   Record.AddNestedNameSpecifierLoc(TL.getQualifierLoc());
836   Record.AddSourceLocation(TL.getTemplateKeywordLoc());
837   Record.AddSourceLocation(TL.getTemplateNameLoc());
838   Record.AddSourceLocation(TL.getLAngleLoc());
839   Record.AddSourceLocation(TL.getRAngleLoc());
840   for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I)
841     Record.AddTemplateArgumentLocInfo(TL.getArgLoc(I).getArgument().getKind(),
842                                       TL.getArgLoc(I).getLocInfo());
843 }
844 
845 void TypeLocWriter::VisitPackExpansionTypeLoc(PackExpansionTypeLoc TL) {
846   Record.AddSourceLocation(TL.getEllipsisLoc());
847 }
848 
849 void TypeLocWriter::VisitObjCInterfaceTypeLoc(ObjCInterfaceTypeLoc TL) {
850   Record.AddSourceLocation(TL.getNameLoc());
851 }
852 
853 void TypeLocWriter::VisitObjCObjectTypeLoc(ObjCObjectTypeLoc TL) {
854   Record.push_back(TL.hasBaseTypeAsWritten());
855   Record.AddSourceLocation(TL.getTypeArgsLAngleLoc());
856   Record.AddSourceLocation(TL.getTypeArgsRAngleLoc());
857   for (unsigned i = 0, e = TL.getNumTypeArgs(); i != e; ++i)
858     Record.AddTypeSourceInfo(TL.getTypeArgTInfo(i));
859   Record.AddSourceLocation(TL.getProtocolLAngleLoc());
860   Record.AddSourceLocation(TL.getProtocolRAngleLoc());
861   for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
862     Record.AddSourceLocation(TL.getProtocolLoc(i));
863 }
864 
865 void TypeLocWriter::VisitObjCObjectPointerTypeLoc(ObjCObjectPointerTypeLoc TL) {
866   Record.AddSourceLocation(TL.getStarLoc());
867 }
868 
869 void TypeLocWriter::VisitAtomicTypeLoc(AtomicTypeLoc TL) {
870   Record.AddSourceLocation(TL.getKWLoc());
871   Record.AddSourceLocation(TL.getLParenLoc());
872   Record.AddSourceLocation(TL.getRParenLoc());
873 }
874 
875 void TypeLocWriter::VisitPipeTypeLoc(PipeTypeLoc TL) {
876   Record.AddSourceLocation(TL.getKWLoc());
877 }
878 
879 void ASTWriter::WriteTypeAbbrevs() {
880   using namespace llvm;
881 
882   std::shared_ptr<BitCodeAbbrev> Abv;
883 
884   // Abbreviation for TYPE_EXT_QUAL
885   Abv = std::make_shared<BitCodeAbbrev>();
886   Abv->Add(BitCodeAbbrevOp(serialization::TYPE_EXT_QUAL));
887   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Type
888   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 3));   // Quals
889   TypeExtQualAbbrev = Stream.EmitAbbrev(std::move(Abv));
890 
891   // Abbreviation for TYPE_FUNCTION_PROTO
892   Abv = std::make_shared<BitCodeAbbrev>();
893   Abv->Add(BitCodeAbbrevOp(serialization::TYPE_FUNCTION_PROTO));
894   // FunctionType
895   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // ReturnType
896   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // NoReturn
897   Abv->Add(BitCodeAbbrevOp(0));                         // HasRegParm
898   Abv->Add(BitCodeAbbrevOp(0));                         // RegParm
899   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // CC
900   Abv->Add(BitCodeAbbrevOp(0));                         // ProducesResult
901   Abv->Add(BitCodeAbbrevOp(0));                         // NoCallerSavedRegs
902   Abv->Add(BitCodeAbbrevOp(0));                         // NoCfCheck
903   // FunctionProtoType
904   Abv->Add(BitCodeAbbrevOp(0));                         // IsVariadic
905   Abv->Add(BitCodeAbbrevOp(0));                         // HasTrailingReturn
906   Abv->Add(BitCodeAbbrevOp(0));                         // TypeQuals
907   Abv->Add(BitCodeAbbrevOp(0));                         // RefQualifier
908   Abv->Add(BitCodeAbbrevOp(EST_None));                  // ExceptionSpec
909   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // NumParams
910   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
911   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Params
912   TypeFunctionProtoAbbrev = Stream.EmitAbbrev(std::move(Abv));
913 }
914 
915 //===----------------------------------------------------------------------===//
916 // ASTWriter Implementation
917 //===----------------------------------------------------------------------===//
918 
919 static void EmitBlockID(unsigned ID, const char *Name,
920                         llvm::BitstreamWriter &Stream,
921                         ASTWriter::RecordDataImpl &Record) {
922   Record.clear();
923   Record.push_back(ID);
924   Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETBID, Record);
925 
926   // Emit the block name if present.
927   if (!Name || Name[0] == 0)
928     return;
929   Record.clear();
930   while (*Name)
931     Record.push_back(*Name++);
932   Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_BLOCKNAME, Record);
933 }
934 
935 static void EmitRecordID(unsigned ID, const char *Name,
936                          llvm::BitstreamWriter &Stream,
937                          ASTWriter::RecordDataImpl &Record) {
938   Record.clear();
939   Record.push_back(ID);
940   while (*Name)
941     Record.push_back(*Name++);
942   Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETRECORDNAME, Record);
943 }
944 
945 static void AddStmtsExprs(llvm::BitstreamWriter &Stream,
946                           ASTWriter::RecordDataImpl &Record) {
947 #define RECORD(X) EmitRecordID(X, #X, Stream, Record)
948   RECORD(STMT_STOP);
949   RECORD(STMT_NULL_PTR);
950   RECORD(STMT_REF_PTR);
951   RECORD(STMT_NULL);
952   RECORD(STMT_COMPOUND);
953   RECORD(STMT_CASE);
954   RECORD(STMT_DEFAULT);
955   RECORD(STMT_LABEL);
956   RECORD(STMT_ATTRIBUTED);
957   RECORD(STMT_IF);
958   RECORD(STMT_SWITCH);
959   RECORD(STMT_WHILE);
960   RECORD(STMT_DO);
961   RECORD(STMT_FOR);
962   RECORD(STMT_GOTO);
963   RECORD(STMT_INDIRECT_GOTO);
964   RECORD(STMT_CONTINUE);
965   RECORD(STMT_BREAK);
966   RECORD(STMT_RETURN);
967   RECORD(STMT_DECL);
968   RECORD(STMT_GCCASM);
969   RECORD(STMT_MSASM);
970   RECORD(EXPR_PREDEFINED);
971   RECORD(EXPR_DECL_REF);
972   RECORD(EXPR_INTEGER_LITERAL);
973   RECORD(EXPR_FLOATING_LITERAL);
974   RECORD(EXPR_IMAGINARY_LITERAL);
975   RECORD(EXPR_STRING_LITERAL);
976   RECORD(EXPR_CHARACTER_LITERAL);
977   RECORD(EXPR_PAREN);
978   RECORD(EXPR_PAREN_LIST);
979   RECORD(EXPR_UNARY_OPERATOR);
980   RECORD(EXPR_SIZEOF_ALIGN_OF);
981   RECORD(EXPR_ARRAY_SUBSCRIPT);
982   RECORD(EXPR_CALL);
983   RECORD(EXPR_MEMBER);
984   RECORD(EXPR_BINARY_OPERATOR);
985   RECORD(EXPR_COMPOUND_ASSIGN_OPERATOR);
986   RECORD(EXPR_CONDITIONAL_OPERATOR);
987   RECORD(EXPR_IMPLICIT_CAST);
988   RECORD(EXPR_CSTYLE_CAST);
989   RECORD(EXPR_COMPOUND_LITERAL);
990   RECORD(EXPR_EXT_VECTOR_ELEMENT);
991   RECORD(EXPR_INIT_LIST);
992   RECORD(EXPR_DESIGNATED_INIT);
993   RECORD(EXPR_DESIGNATED_INIT_UPDATE);
994   RECORD(EXPR_IMPLICIT_VALUE_INIT);
995   RECORD(EXPR_NO_INIT);
996   RECORD(EXPR_VA_ARG);
997   RECORD(EXPR_ADDR_LABEL);
998   RECORD(EXPR_STMT);
999   RECORD(EXPR_CHOOSE);
1000   RECORD(EXPR_GNU_NULL);
1001   RECORD(EXPR_SHUFFLE_VECTOR);
1002   RECORD(EXPR_BLOCK);
1003   RECORD(EXPR_GENERIC_SELECTION);
1004   RECORD(EXPR_OBJC_STRING_LITERAL);
1005   RECORD(EXPR_OBJC_BOXED_EXPRESSION);
1006   RECORD(EXPR_OBJC_ARRAY_LITERAL);
1007   RECORD(EXPR_OBJC_DICTIONARY_LITERAL);
1008   RECORD(EXPR_OBJC_ENCODE);
1009   RECORD(EXPR_OBJC_SELECTOR_EXPR);
1010   RECORD(EXPR_OBJC_PROTOCOL_EXPR);
1011   RECORD(EXPR_OBJC_IVAR_REF_EXPR);
1012   RECORD(EXPR_OBJC_PROPERTY_REF_EXPR);
1013   RECORD(EXPR_OBJC_KVC_REF_EXPR);
1014   RECORD(EXPR_OBJC_MESSAGE_EXPR);
1015   RECORD(STMT_OBJC_FOR_COLLECTION);
1016   RECORD(STMT_OBJC_CATCH);
1017   RECORD(STMT_OBJC_FINALLY);
1018   RECORD(STMT_OBJC_AT_TRY);
1019   RECORD(STMT_OBJC_AT_SYNCHRONIZED);
1020   RECORD(STMT_OBJC_AT_THROW);
1021   RECORD(EXPR_OBJC_BOOL_LITERAL);
1022   RECORD(STMT_CXX_CATCH);
1023   RECORD(STMT_CXX_TRY);
1024   RECORD(STMT_CXX_FOR_RANGE);
1025   RECORD(EXPR_CXX_OPERATOR_CALL);
1026   RECORD(EXPR_CXX_MEMBER_CALL);
1027   RECORD(EXPR_CXX_CONSTRUCT);
1028   RECORD(EXPR_CXX_TEMPORARY_OBJECT);
1029   RECORD(EXPR_CXX_STATIC_CAST);
1030   RECORD(EXPR_CXX_DYNAMIC_CAST);
1031   RECORD(EXPR_CXX_REINTERPRET_CAST);
1032   RECORD(EXPR_CXX_CONST_CAST);
1033   RECORD(EXPR_CXX_FUNCTIONAL_CAST);
1034   RECORD(EXPR_USER_DEFINED_LITERAL);
1035   RECORD(EXPR_CXX_STD_INITIALIZER_LIST);
1036   RECORD(EXPR_CXX_BOOL_LITERAL);
1037   RECORD(EXPR_CXX_NULL_PTR_LITERAL);
1038   RECORD(EXPR_CXX_TYPEID_EXPR);
1039   RECORD(EXPR_CXX_TYPEID_TYPE);
1040   RECORD(EXPR_CXX_THIS);
1041   RECORD(EXPR_CXX_THROW);
1042   RECORD(EXPR_CXX_DEFAULT_ARG);
1043   RECORD(EXPR_CXX_DEFAULT_INIT);
1044   RECORD(EXPR_CXX_BIND_TEMPORARY);
1045   RECORD(EXPR_CXX_SCALAR_VALUE_INIT);
1046   RECORD(EXPR_CXX_NEW);
1047   RECORD(EXPR_CXX_DELETE);
1048   RECORD(EXPR_CXX_PSEUDO_DESTRUCTOR);
1049   RECORD(EXPR_EXPR_WITH_CLEANUPS);
1050   RECORD(EXPR_CXX_DEPENDENT_SCOPE_MEMBER);
1051   RECORD(EXPR_CXX_DEPENDENT_SCOPE_DECL_REF);
1052   RECORD(EXPR_CXX_UNRESOLVED_CONSTRUCT);
1053   RECORD(EXPR_CXX_UNRESOLVED_MEMBER);
1054   RECORD(EXPR_CXX_UNRESOLVED_LOOKUP);
1055   RECORD(EXPR_CXX_EXPRESSION_TRAIT);
1056   RECORD(EXPR_CXX_NOEXCEPT);
1057   RECORD(EXPR_OPAQUE_VALUE);
1058   RECORD(EXPR_BINARY_CONDITIONAL_OPERATOR);
1059   RECORD(EXPR_TYPE_TRAIT);
1060   RECORD(EXPR_ARRAY_TYPE_TRAIT);
1061   RECORD(EXPR_PACK_EXPANSION);
1062   RECORD(EXPR_SIZEOF_PACK);
1063   RECORD(EXPR_SUBST_NON_TYPE_TEMPLATE_PARM);
1064   RECORD(EXPR_SUBST_NON_TYPE_TEMPLATE_PARM_PACK);
1065   RECORD(EXPR_FUNCTION_PARM_PACK);
1066   RECORD(EXPR_MATERIALIZE_TEMPORARY);
1067   RECORD(EXPR_CUDA_KERNEL_CALL);
1068   RECORD(EXPR_CXX_UUIDOF_EXPR);
1069   RECORD(EXPR_CXX_UUIDOF_TYPE);
1070   RECORD(EXPR_LAMBDA);
1071 #undef RECORD
1072 }
1073 
1074 void ASTWriter::WriteBlockInfoBlock() {
1075   RecordData Record;
1076   Stream.EnterBlockInfoBlock();
1077 
1078 #define BLOCK(X) EmitBlockID(X ## _ID, #X, Stream, Record)
1079 #define RECORD(X) EmitRecordID(X, #X, Stream, Record)
1080 
1081   // Control Block.
1082   BLOCK(CONTROL_BLOCK);
1083   RECORD(METADATA);
1084   RECORD(MODULE_NAME);
1085   RECORD(MODULE_DIRECTORY);
1086   RECORD(MODULE_MAP_FILE);
1087   RECORD(IMPORTS);
1088   RECORD(ORIGINAL_FILE);
1089   RECORD(ORIGINAL_PCH_DIR);
1090   RECORD(ORIGINAL_FILE_ID);
1091   RECORD(INPUT_FILE_OFFSETS);
1092 
1093   BLOCK(OPTIONS_BLOCK);
1094   RECORD(LANGUAGE_OPTIONS);
1095   RECORD(TARGET_OPTIONS);
1096   RECORD(FILE_SYSTEM_OPTIONS);
1097   RECORD(HEADER_SEARCH_OPTIONS);
1098   RECORD(PREPROCESSOR_OPTIONS);
1099 
1100   BLOCK(INPUT_FILES_BLOCK);
1101   RECORD(INPUT_FILE);
1102   RECORD(INPUT_FILE_HASH);
1103 
1104   // AST Top-Level Block.
1105   BLOCK(AST_BLOCK);
1106   RECORD(TYPE_OFFSET);
1107   RECORD(DECL_OFFSET);
1108   RECORD(IDENTIFIER_OFFSET);
1109   RECORD(IDENTIFIER_TABLE);
1110   RECORD(EAGERLY_DESERIALIZED_DECLS);
1111   RECORD(MODULAR_CODEGEN_DECLS);
1112   RECORD(SPECIAL_TYPES);
1113   RECORD(STATISTICS);
1114   RECORD(TENTATIVE_DEFINITIONS);
1115   RECORD(SELECTOR_OFFSETS);
1116   RECORD(METHOD_POOL);
1117   RECORD(PP_COUNTER_VALUE);
1118   RECORD(SOURCE_LOCATION_OFFSETS);
1119   RECORD(SOURCE_LOCATION_PRELOADS);
1120   RECORD(EXT_VECTOR_DECLS);
1121   RECORD(UNUSED_FILESCOPED_DECLS);
1122   RECORD(PPD_ENTITIES_OFFSETS);
1123   RECORD(VTABLE_USES);
1124   RECORD(PPD_SKIPPED_RANGES);
1125   RECORD(REFERENCED_SELECTOR_POOL);
1126   RECORD(TU_UPDATE_LEXICAL);
1127   RECORD(SEMA_DECL_REFS);
1128   RECORD(WEAK_UNDECLARED_IDENTIFIERS);
1129   RECORD(PENDING_IMPLICIT_INSTANTIATIONS);
1130   RECORD(UPDATE_VISIBLE);
1131   RECORD(DECL_UPDATE_OFFSETS);
1132   RECORD(DECL_UPDATES);
1133   RECORD(CUDA_SPECIAL_DECL_REFS);
1134   RECORD(HEADER_SEARCH_TABLE);
1135   RECORD(FP_PRAGMA_OPTIONS);
1136   RECORD(OPENCL_EXTENSIONS);
1137   RECORD(OPENCL_EXTENSION_TYPES);
1138   RECORD(OPENCL_EXTENSION_DECLS);
1139   RECORD(DELEGATING_CTORS);
1140   RECORD(KNOWN_NAMESPACES);
1141   RECORD(MODULE_OFFSET_MAP);
1142   RECORD(SOURCE_MANAGER_LINE_TABLE);
1143   RECORD(OBJC_CATEGORIES_MAP);
1144   RECORD(FILE_SORTED_DECLS);
1145   RECORD(IMPORTED_MODULES);
1146   RECORD(OBJC_CATEGORIES);
1147   RECORD(MACRO_OFFSET);
1148   RECORD(INTERESTING_IDENTIFIERS);
1149   RECORD(UNDEFINED_BUT_USED);
1150   RECORD(LATE_PARSED_TEMPLATE);
1151   RECORD(OPTIMIZE_PRAGMA_OPTIONS);
1152   RECORD(MSSTRUCT_PRAGMA_OPTIONS);
1153   RECORD(POINTERS_TO_MEMBERS_PRAGMA_OPTIONS);
1154   RECORD(UNUSED_LOCAL_TYPEDEF_NAME_CANDIDATES);
1155   RECORD(DELETE_EXPRS_TO_ANALYZE);
1156   RECORD(CUDA_PRAGMA_FORCE_HOST_DEVICE_DEPTH);
1157   RECORD(PP_CONDITIONAL_STACK);
1158 
1159   // SourceManager Block.
1160   BLOCK(SOURCE_MANAGER_BLOCK);
1161   RECORD(SM_SLOC_FILE_ENTRY);
1162   RECORD(SM_SLOC_BUFFER_ENTRY);
1163   RECORD(SM_SLOC_BUFFER_BLOB);
1164   RECORD(SM_SLOC_BUFFER_BLOB_COMPRESSED);
1165   RECORD(SM_SLOC_EXPANSION_ENTRY);
1166 
1167   // Preprocessor Block.
1168   BLOCK(PREPROCESSOR_BLOCK);
1169   RECORD(PP_MACRO_DIRECTIVE_HISTORY);
1170   RECORD(PP_MACRO_FUNCTION_LIKE);
1171   RECORD(PP_MACRO_OBJECT_LIKE);
1172   RECORD(PP_MODULE_MACRO);
1173   RECORD(PP_TOKEN);
1174 
1175   // Submodule Block.
1176   BLOCK(SUBMODULE_BLOCK);
1177   RECORD(SUBMODULE_METADATA);
1178   RECORD(SUBMODULE_DEFINITION);
1179   RECORD(SUBMODULE_UMBRELLA_HEADER);
1180   RECORD(SUBMODULE_HEADER);
1181   RECORD(SUBMODULE_TOPHEADER);
1182   RECORD(SUBMODULE_UMBRELLA_DIR);
1183   RECORD(SUBMODULE_IMPORTS);
1184   RECORD(SUBMODULE_EXPORTS);
1185   RECORD(SUBMODULE_REQUIRES);
1186   RECORD(SUBMODULE_EXCLUDED_HEADER);
1187   RECORD(SUBMODULE_LINK_LIBRARY);
1188   RECORD(SUBMODULE_CONFIG_MACRO);
1189   RECORD(SUBMODULE_CONFLICT);
1190   RECORD(SUBMODULE_PRIVATE_HEADER);
1191   RECORD(SUBMODULE_TEXTUAL_HEADER);
1192   RECORD(SUBMODULE_PRIVATE_TEXTUAL_HEADER);
1193   RECORD(SUBMODULE_INITIALIZERS);
1194   RECORD(SUBMODULE_EXPORT_AS);
1195 
1196   // Comments Block.
1197   BLOCK(COMMENTS_BLOCK);
1198   RECORD(COMMENTS_RAW_COMMENT);
1199 
1200   // Decls and Types block.
1201   BLOCK(DECLTYPES_BLOCK);
1202   RECORD(TYPE_EXT_QUAL);
1203   RECORD(TYPE_COMPLEX);
1204   RECORD(TYPE_POINTER);
1205   RECORD(TYPE_BLOCK_POINTER);
1206   RECORD(TYPE_LVALUE_REFERENCE);
1207   RECORD(TYPE_RVALUE_REFERENCE);
1208   RECORD(TYPE_MEMBER_POINTER);
1209   RECORD(TYPE_CONSTANT_ARRAY);
1210   RECORD(TYPE_INCOMPLETE_ARRAY);
1211   RECORD(TYPE_VARIABLE_ARRAY);
1212   RECORD(TYPE_VECTOR);
1213   RECORD(TYPE_EXT_VECTOR);
1214   RECORD(TYPE_FUNCTION_NO_PROTO);
1215   RECORD(TYPE_FUNCTION_PROTO);
1216   RECORD(TYPE_TYPEDEF);
1217   RECORD(TYPE_TYPEOF_EXPR);
1218   RECORD(TYPE_TYPEOF);
1219   RECORD(TYPE_RECORD);
1220   RECORD(TYPE_ENUM);
1221   RECORD(TYPE_OBJC_INTERFACE);
1222   RECORD(TYPE_OBJC_OBJECT_POINTER);
1223   RECORD(TYPE_DECLTYPE);
1224   RECORD(TYPE_ELABORATED);
1225   RECORD(TYPE_SUBST_TEMPLATE_TYPE_PARM);
1226   RECORD(TYPE_UNRESOLVED_USING);
1227   RECORD(TYPE_INJECTED_CLASS_NAME);
1228   RECORD(TYPE_OBJC_OBJECT);
1229   RECORD(TYPE_TEMPLATE_TYPE_PARM);
1230   RECORD(TYPE_TEMPLATE_SPECIALIZATION);
1231   RECORD(TYPE_DEPENDENT_NAME);
1232   RECORD(TYPE_DEPENDENT_TEMPLATE_SPECIALIZATION);
1233   RECORD(TYPE_DEPENDENT_SIZED_ARRAY);
1234   RECORD(TYPE_PAREN);
1235   RECORD(TYPE_MACRO_QUALIFIED);
1236   RECORD(TYPE_PACK_EXPANSION);
1237   RECORD(TYPE_ATTRIBUTED);
1238   RECORD(TYPE_SUBST_TEMPLATE_TYPE_PARM_PACK);
1239   RECORD(TYPE_AUTO);
1240   RECORD(TYPE_UNARY_TRANSFORM);
1241   RECORD(TYPE_ATOMIC);
1242   RECORD(TYPE_DECAYED);
1243   RECORD(TYPE_ADJUSTED);
1244   RECORD(TYPE_OBJC_TYPE_PARAM);
1245   RECORD(LOCAL_REDECLARATIONS);
1246   RECORD(DECL_TYPEDEF);
1247   RECORD(DECL_TYPEALIAS);
1248   RECORD(DECL_ENUM);
1249   RECORD(DECL_RECORD);
1250   RECORD(DECL_ENUM_CONSTANT);
1251   RECORD(DECL_FUNCTION);
1252   RECORD(DECL_OBJC_METHOD);
1253   RECORD(DECL_OBJC_INTERFACE);
1254   RECORD(DECL_OBJC_PROTOCOL);
1255   RECORD(DECL_OBJC_IVAR);
1256   RECORD(DECL_OBJC_AT_DEFS_FIELD);
1257   RECORD(DECL_OBJC_CATEGORY);
1258   RECORD(DECL_OBJC_CATEGORY_IMPL);
1259   RECORD(DECL_OBJC_IMPLEMENTATION);
1260   RECORD(DECL_OBJC_COMPATIBLE_ALIAS);
1261   RECORD(DECL_OBJC_PROPERTY);
1262   RECORD(DECL_OBJC_PROPERTY_IMPL);
1263   RECORD(DECL_FIELD);
1264   RECORD(DECL_MS_PROPERTY);
1265   RECORD(DECL_VAR);
1266   RECORD(DECL_IMPLICIT_PARAM);
1267   RECORD(DECL_PARM_VAR);
1268   RECORD(DECL_FILE_SCOPE_ASM);
1269   RECORD(DECL_BLOCK);
1270   RECORD(DECL_CONTEXT_LEXICAL);
1271   RECORD(DECL_CONTEXT_VISIBLE);
1272   RECORD(DECL_NAMESPACE);
1273   RECORD(DECL_NAMESPACE_ALIAS);
1274   RECORD(DECL_USING);
1275   RECORD(DECL_USING_SHADOW);
1276   RECORD(DECL_USING_DIRECTIVE);
1277   RECORD(DECL_UNRESOLVED_USING_VALUE);
1278   RECORD(DECL_UNRESOLVED_USING_TYPENAME);
1279   RECORD(DECL_LINKAGE_SPEC);
1280   RECORD(DECL_CXX_RECORD);
1281   RECORD(DECL_CXX_METHOD);
1282   RECORD(DECL_CXX_CONSTRUCTOR);
1283   RECORD(DECL_CXX_DESTRUCTOR);
1284   RECORD(DECL_CXX_CONVERSION);
1285   RECORD(DECL_ACCESS_SPEC);
1286   RECORD(DECL_FRIEND);
1287   RECORD(DECL_FRIEND_TEMPLATE);
1288   RECORD(DECL_CLASS_TEMPLATE);
1289   RECORD(DECL_CLASS_TEMPLATE_SPECIALIZATION);
1290   RECORD(DECL_CLASS_TEMPLATE_PARTIAL_SPECIALIZATION);
1291   RECORD(DECL_VAR_TEMPLATE);
1292   RECORD(DECL_VAR_TEMPLATE_SPECIALIZATION);
1293   RECORD(DECL_VAR_TEMPLATE_PARTIAL_SPECIALIZATION);
1294   RECORD(DECL_FUNCTION_TEMPLATE);
1295   RECORD(DECL_TEMPLATE_TYPE_PARM);
1296   RECORD(DECL_NON_TYPE_TEMPLATE_PARM);
1297   RECORD(DECL_TEMPLATE_TEMPLATE_PARM);
1298   RECORD(DECL_CONCEPT);
1299   RECORD(DECL_TYPE_ALIAS_TEMPLATE);
1300   RECORD(DECL_STATIC_ASSERT);
1301   RECORD(DECL_CXX_BASE_SPECIFIERS);
1302   RECORD(DECL_CXX_CTOR_INITIALIZERS);
1303   RECORD(DECL_INDIRECTFIELD);
1304   RECORD(DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK);
1305   RECORD(DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK);
1306   RECORD(DECL_CLASS_SCOPE_FUNCTION_SPECIALIZATION);
1307   RECORD(DECL_IMPORT);
1308   RECORD(DECL_OMP_THREADPRIVATE);
1309   RECORD(DECL_EMPTY);
1310   RECORD(DECL_OBJC_TYPE_PARAM);
1311   RECORD(DECL_OMP_CAPTUREDEXPR);
1312   RECORD(DECL_PRAGMA_COMMENT);
1313   RECORD(DECL_PRAGMA_DETECT_MISMATCH);
1314   RECORD(DECL_OMP_DECLARE_REDUCTION);
1315   RECORD(DECL_OMP_ALLOCATE);
1316 
1317   // Statements and Exprs can occur in the Decls and Types block.
1318   AddStmtsExprs(Stream, Record);
1319 
1320   BLOCK(PREPROCESSOR_DETAIL_BLOCK);
1321   RECORD(PPD_MACRO_EXPANSION);
1322   RECORD(PPD_MACRO_DEFINITION);
1323   RECORD(PPD_INCLUSION_DIRECTIVE);
1324 
1325   // Decls and Types block.
1326   BLOCK(EXTENSION_BLOCK);
1327   RECORD(EXTENSION_METADATA);
1328 
1329   BLOCK(UNHASHED_CONTROL_BLOCK);
1330   RECORD(SIGNATURE);
1331   RECORD(DIAGNOSTIC_OPTIONS);
1332   RECORD(DIAG_PRAGMA_MAPPINGS);
1333 
1334 #undef RECORD
1335 #undef BLOCK
1336   Stream.ExitBlock();
1337 }
1338 
1339 /// Prepares a path for being written to an AST file by converting it
1340 /// to an absolute path and removing nested './'s.
1341 ///
1342 /// \return \c true if the path was changed.
1343 static bool cleanPathForOutput(FileManager &FileMgr,
1344                                SmallVectorImpl<char> &Path) {
1345   bool Changed = FileMgr.makeAbsolutePath(Path);
1346   return Changed | llvm::sys::path::remove_dots(Path);
1347 }
1348 
1349 /// Adjusts the given filename to only write out the portion of the
1350 /// filename that is not part of the system root directory.
1351 ///
1352 /// \param Filename the file name to adjust.
1353 ///
1354 /// \param BaseDir When non-NULL, the PCH file is a relocatable AST file and
1355 /// the returned filename will be adjusted by this root directory.
1356 ///
1357 /// \returns either the original filename (if it needs no adjustment) or the
1358 /// adjusted filename (which points into the @p Filename parameter).
1359 static const char *
1360 adjustFilenameForRelocatableAST(const char *Filename, StringRef BaseDir) {
1361   assert(Filename && "No file name to adjust?");
1362 
1363   if (BaseDir.empty())
1364     return Filename;
1365 
1366   // Verify that the filename and the system root have the same prefix.
1367   unsigned Pos = 0;
1368   for (; Filename[Pos] && Pos < BaseDir.size(); ++Pos)
1369     if (Filename[Pos] != BaseDir[Pos])
1370       return Filename; // Prefixes don't match.
1371 
1372   // We hit the end of the filename before we hit the end of the system root.
1373   if (!Filename[Pos])
1374     return Filename;
1375 
1376   // If there's not a path separator at the end of the base directory nor
1377   // immediately after it, then this isn't within the base directory.
1378   if (!llvm::sys::path::is_separator(Filename[Pos])) {
1379     if (!llvm::sys::path::is_separator(BaseDir.back()))
1380       return Filename;
1381   } else {
1382     // If the file name has a '/' at the current position, skip over the '/'.
1383     // We distinguish relative paths from absolute paths by the
1384     // absence of '/' at the beginning of relative paths.
1385     //
1386     // FIXME: This is wrong. We distinguish them by asking if the path is
1387     // absolute, which isn't the same thing. And there might be multiple '/'s
1388     // in a row. Use a better mechanism to indicate whether we have emitted an
1389     // absolute or relative path.
1390     ++Pos;
1391   }
1392 
1393   return Filename + Pos;
1394 }
1395 
1396 ASTFileSignature ASTWriter::createSignature(StringRef Bytes) {
1397   // Calculate the hash till start of UNHASHED_CONTROL_BLOCK.
1398   llvm::SHA1 Hasher;
1399   Hasher.update(ArrayRef<uint8_t>(Bytes.bytes_begin(), Bytes.size()));
1400   auto Hash = Hasher.result();
1401 
1402   // Convert to an array [5*i32].
1403   ASTFileSignature Signature;
1404   auto LShift = [&](unsigned char Val, unsigned Shift) {
1405     return (uint32_t)Val << Shift;
1406   };
1407   for (int I = 0; I != 5; ++I)
1408     Signature[I] = LShift(Hash[I * 4 + 0], 24) | LShift(Hash[I * 4 + 1], 16) |
1409                    LShift(Hash[I * 4 + 2], 8) | LShift(Hash[I * 4 + 3], 0);
1410 
1411   return Signature;
1412 }
1413 
1414 ASTFileSignature ASTWriter::writeUnhashedControlBlock(Preprocessor &PP,
1415                                                       ASTContext &Context) {
1416   // Flush first to prepare the PCM hash (signature).
1417   Stream.FlushToWord();
1418   auto StartOfUnhashedControl = Stream.GetCurrentBitNo() >> 3;
1419 
1420   // Enter the block and prepare to write records.
1421   RecordData Record;
1422   Stream.EnterSubblock(UNHASHED_CONTROL_BLOCK_ID, 5);
1423 
1424   // For implicit modules, write the hash of the PCM as its signature.
1425   ASTFileSignature Signature;
1426   if (WritingModule &&
1427       PP.getHeaderSearchInfo().getHeaderSearchOpts().ModulesHashContent) {
1428     Signature = createSignature(StringRef(Buffer.begin(), StartOfUnhashedControl));
1429     Record.append(Signature.begin(), Signature.end());
1430     Stream.EmitRecord(SIGNATURE, Record);
1431     Record.clear();
1432   }
1433 
1434   // Diagnostic options.
1435   const auto &Diags = Context.getDiagnostics();
1436   const DiagnosticOptions &DiagOpts = Diags.getDiagnosticOptions();
1437 #define DIAGOPT(Name, Bits, Default) Record.push_back(DiagOpts.Name);
1438 #define ENUM_DIAGOPT(Name, Type, Bits, Default)                                \
1439   Record.push_back(static_cast<unsigned>(DiagOpts.get##Name()));
1440 #include "clang/Basic/DiagnosticOptions.def"
1441   Record.push_back(DiagOpts.Warnings.size());
1442   for (unsigned I = 0, N = DiagOpts.Warnings.size(); I != N; ++I)
1443     AddString(DiagOpts.Warnings[I], Record);
1444   Record.push_back(DiagOpts.Remarks.size());
1445   for (unsigned I = 0, N = DiagOpts.Remarks.size(); I != N; ++I)
1446     AddString(DiagOpts.Remarks[I], Record);
1447   // Note: we don't serialize the log or serialization file names, because they
1448   // are generally transient files and will almost always be overridden.
1449   Stream.EmitRecord(DIAGNOSTIC_OPTIONS, Record);
1450 
1451   // Write out the diagnostic/pragma mappings.
1452   WritePragmaDiagnosticMappings(Diags, /* isModule = */ WritingModule);
1453 
1454   // Leave the options block.
1455   Stream.ExitBlock();
1456   return Signature;
1457 }
1458 
1459 /// Write the control block.
1460 void ASTWriter::WriteControlBlock(Preprocessor &PP, ASTContext &Context,
1461                                   StringRef isysroot,
1462                                   const std::string &OutputFile) {
1463   using namespace llvm;
1464 
1465   Stream.EnterSubblock(CONTROL_BLOCK_ID, 5);
1466   RecordData Record;
1467 
1468   // Metadata
1469   auto MetadataAbbrev = std::make_shared<BitCodeAbbrev>();
1470   MetadataAbbrev->Add(BitCodeAbbrevOp(METADATA));
1471   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Major
1472   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Minor
1473   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Clang maj.
1474   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Clang min.
1475   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Relocatable
1476   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Timestamps
1477   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // PCHHasObjectFile
1478   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Errors
1479   MetadataAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // SVN branch/tag
1480   unsigned MetadataAbbrevCode = Stream.EmitAbbrev(std::move(MetadataAbbrev));
1481   assert((!WritingModule || isysroot.empty()) &&
1482          "writing module as a relocatable PCH?");
1483   {
1484     RecordData::value_type Record[] = {
1485         METADATA,
1486         VERSION_MAJOR,
1487         VERSION_MINOR,
1488         CLANG_VERSION_MAJOR,
1489         CLANG_VERSION_MINOR,
1490         !isysroot.empty(),
1491         IncludeTimestamps,
1492         Context.getLangOpts().BuildingPCHWithObjectFile,
1493         ASTHasCompilerErrors};
1494     Stream.EmitRecordWithBlob(MetadataAbbrevCode, Record,
1495                               getClangFullRepositoryVersion());
1496   }
1497 
1498   if (WritingModule) {
1499     // Module name
1500     auto Abbrev = std::make_shared<BitCodeAbbrev>();
1501     Abbrev->Add(BitCodeAbbrevOp(MODULE_NAME));
1502     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
1503     unsigned AbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
1504     RecordData::value_type Record[] = {MODULE_NAME};
1505     Stream.EmitRecordWithBlob(AbbrevCode, Record, WritingModule->Name);
1506   }
1507 
1508   if (WritingModule && WritingModule->Directory) {
1509     SmallString<128> BaseDir(WritingModule->Directory->getName());
1510     cleanPathForOutput(Context.getSourceManager().getFileManager(), BaseDir);
1511 
1512     // If the home of the module is the current working directory, then we
1513     // want to pick up the cwd of the build process loading the module, not
1514     // our cwd, when we load this module.
1515     if (!PP.getHeaderSearchInfo()
1516              .getHeaderSearchOpts()
1517              .ModuleMapFileHomeIsCwd ||
1518         WritingModule->Directory->getName() != StringRef(".")) {
1519       // Module directory.
1520       auto Abbrev = std::make_shared<BitCodeAbbrev>();
1521       Abbrev->Add(BitCodeAbbrevOp(MODULE_DIRECTORY));
1522       Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Directory
1523       unsigned AbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
1524 
1525       RecordData::value_type Record[] = {MODULE_DIRECTORY};
1526       Stream.EmitRecordWithBlob(AbbrevCode, Record, BaseDir);
1527     }
1528 
1529     // Write out all other paths relative to the base directory if possible.
1530     BaseDirectory.assign(BaseDir.begin(), BaseDir.end());
1531   } else if (!isysroot.empty()) {
1532     // Write out paths relative to the sysroot if possible.
1533     BaseDirectory = isysroot;
1534   }
1535 
1536   // Module map file
1537   if (WritingModule && WritingModule->Kind == Module::ModuleMapModule) {
1538     Record.clear();
1539 
1540     auto &Map = PP.getHeaderSearchInfo().getModuleMap();
1541     AddPath(WritingModule->PresumedModuleMapFile.empty()
1542                 ? Map.getModuleMapFileForUniquing(WritingModule)->getName()
1543                 : StringRef(WritingModule->PresumedModuleMapFile),
1544             Record);
1545 
1546     // Additional module map files.
1547     if (auto *AdditionalModMaps =
1548             Map.getAdditionalModuleMapFiles(WritingModule)) {
1549       Record.push_back(AdditionalModMaps->size());
1550       for (const FileEntry *F : *AdditionalModMaps)
1551         AddPath(F->getName(), Record);
1552     } else {
1553       Record.push_back(0);
1554     }
1555 
1556     Stream.EmitRecord(MODULE_MAP_FILE, Record);
1557   }
1558 
1559   // Imports
1560   if (Chain) {
1561     serialization::ModuleManager &Mgr = Chain->getModuleManager();
1562     Record.clear();
1563 
1564     for (ModuleFile &M : Mgr) {
1565       // Skip modules that weren't directly imported.
1566       if (!M.isDirectlyImported())
1567         continue;
1568 
1569       Record.push_back((unsigned)M.Kind); // FIXME: Stable encoding
1570       AddSourceLocation(M.ImportLoc, Record);
1571 
1572       // If we have calculated signature, there is no need to store
1573       // the size or timestamp.
1574       Record.push_back(M.Signature ? 0 : M.File->getSize());
1575       Record.push_back(M.Signature ? 0 : getTimestampForOutput(M.File));
1576 
1577       for (auto I : M.Signature)
1578         Record.push_back(I);
1579 
1580       AddString(M.ModuleName, Record);
1581       AddPath(M.FileName, Record);
1582     }
1583     Stream.EmitRecord(IMPORTS, Record);
1584   }
1585 
1586   // Write the options block.
1587   Stream.EnterSubblock(OPTIONS_BLOCK_ID, 4);
1588 
1589   // Language options.
1590   Record.clear();
1591   const LangOptions &LangOpts = Context.getLangOpts();
1592 #define LANGOPT(Name, Bits, Default, Description) \
1593   Record.push_back(LangOpts.Name);
1594 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
1595   Record.push_back(static_cast<unsigned>(LangOpts.get##Name()));
1596 #include "clang/Basic/LangOptions.def"
1597 #define SANITIZER(NAME, ID)                                                    \
1598   Record.push_back(LangOpts.Sanitize.has(SanitizerKind::ID));
1599 #include "clang/Basic/Sanitizers.def"
1600 
1601   Record.push_back(LangOpts.ModuleFeatures.size());
1602   for (StringRef Feature : LangOpts.ModuleFeatures)
1603     AddString(Feature, Record);
1604 
1605   Record.push_back((unsigned) LangOpts.ObjCRuntime.getKind());
1606   AddVersionTuple(LangOpts.ObjCRuntime.getVersion(), Record);
1607 
1608   AddString(LangOpts.CurrentModule, Record);
1609 
1610   // Comment options.
1611   Record.push_back(LangOpts.CommentOpts.BlockCommandNames.size());
1612   for (const auto &I : LangOpts.CommentOpts.BlockCommandNames) {
1613     AddString(I, Record);
1614   }
1615   Record.push_back(LangOpts.CommentOpts.ParseAllComments);
1616 
1617   // OpenMP offloading options.
1618   Record.push_back(LangOpts.OMPTargetTriples.size());
1619   for (auto &T : LangOpts.OMPTargetTriples)
1620     AddString(T.getTriple(), Record);
1621 
1622   AddString(LangOpts.OMPHostIRFile, Record);
1623 
1624   Stream.EmitRecord(LANGUAGE_OPTIONS, Record);
1625 
1626   // Target options.
1627   Record.clear();
1628   const TargetInfo &Target = Context.getTargetInfo();
1629   const TargetOptions &TargetOpts = Target.getTargetOpts();
1630   AddString(TargetOpts.Triple, Record);
1631   AddString(TargetOpts.CPU, Record);
1632   AddString(TargetOpts.ABI, Record);
1633   Record.push_back(TargetOpts.FeaturesAsWritten.size());
1634   for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size(); I != N; ++I) {
1635     AddString(TargetOpts.FeaturesAsWritten[I], Record);
1636   }
1637   Record.push_back(TargetOpts.Features.size());
1638   for (unsigned I = 0, N = TargetOpts.Features.size(); I != N; ++I) {
1639     AddString(TargetOpts.Features[I], Record);
1640   }
1641   Stream.EmitRecord(TARGET_OPTIONS, Record);
1642 
1643   // File system options.
1644   Record.clear();
1645   const FileSystemOptions &FSOpts =
1646       Context.getSourceManager().getFileManager().getFileSystemOpts();
1647   AddString(FSOpts.WorkingDir, Record);
1648   Stream.EmitRecord(FILE_SYSTEM_OPTIONS, Record);
1649 
1650   // Header search options.
1651   Record.clear();
1652   const HeaderSearchOptions &HSOpts
1653     = PP.getHeaderSearchInfo().getHeaderSearchOpts();
1654   AddString(HSOpts.Sysroot, Record);
1655 
1656   // Include entries.
1657   Record.push_back(HSOpts.UserEntries.size());
1658   for (unsigned I = 0, N = HSOpts.UserEntries.size(); I != N; ++I) {
1659     const HeaderSearchOptions::Entry &Entry = HSOpts.UserEntries[I];
1660     AddString(Entry.Path, Record);
1661     Record.push_back(static_cast<unsigned>(Entry.Group));
1662     Record.push_back(Entry.IsFramework);
1663     Record.push_back(Entry.IgnoreSysRoot);
1664   }
1665 
1666   // System header prefixes.
1667   Record.push_back(HSOpts.SystemHeaderPrefixes.size());
1668   for (unsigned I = 0, N = HSOpts.SystemHeaderPrefixes.size(); I != N; ++I) {
1669     AddString(HSOpts.SystemHeaderPrefixes[I].Prefix, Record);
1670     Record.push_back(HSOpts.SystemHeaderPrefixes[I].IsSystemHeader);
1671   }
1672 
1673   AddString(HSOpts.ResourceDir, Record);
1674   AddString(HSOpts.ModuleCachePath, Record);
1675   AddString(HSOpts.ModuleUserBuildPath, Record);
1676   Record.push_back(HSOpts.DisableModuleHash);
1677   Record.push_back(HSOpts.ImplicitModuleMaps);
1678   Record.push_back(HSOpts.ModuleMapFileHomeIsCwd);
1679   Record.push_back(HSOpts.UseBuiltinIncludes);
1680   Record.push_back(HSOpts.UseStandardSystemIncludes);
1681   Record.push_back(HSOpts.UseStandardCXXIncludes);
1682   Record.push_back(HSOpts.UseLibcxx);
1683   // Write out the specific module cache path that contains the module files.
1684   AddString(PP.getHeaderSearchInfo().getModuleCachePath(), Record);
1685   Stream.EmitRecord(HEADER_SEARCH_OPTIONS, Record);
1686 
1687   // Preprocessor options.
1688   Record.clear();
1689   const PreprocessorOptions &PPOpts = PP.getPreprocessorOpts();
1690 
1691   // Macro definitions.
1692   Record.push_back(PPOpts.Macros.size());
1693   for (unsigned I = 0, N = PPOpts.Macros.size(); I != N; ++I) {
1694     AddString(PPOpts.Macros[I].first, Record);
1695     Record.push_back(PPOpts.Macros[I].second);
1696   }
1697 
1698   // Includes
1699   Record.push_back(PPOpts.Includes.size());
1700   for (unsigned I = 0, N = PPOpts.Includes.size(); I != N; ++I)
1701     AddString(PPOpts.Includes[I], Record);
1702 
1703   // Macro includes
1704   Record.push_back(PPOpts.MacroIncludes.size());
1705   for (unsigned I = 0, N = PPOpts.MacroIncludes.size(); I != N; ++I)
1706     AddString(PPOpts.MacroIncludes[I], Record);
1707 
1708   Record.push_back(PPOpts.UsePredefines);
1709   // Detailed record is important since it is used for the module cache hash.
1710   Record.push_back(PPOpts.DetailedRecord);
1711   AddString(PPOpts.ImplicitPCHInclude, Record);
1712   Record.push_back(static_cast<unsigned>(PPOpts.ObjCXXARCStandardLibrary));
1713   Stream.EmitRecord(PREPROCESSOR_OPTIONS, Record);
1714 
1715   // Leave the options block.
1716   Stream.ExitBlock();
1717 
1718   // Original file name and file ID
1719   SourceManager &SM = Context.getSourceManager();
1720   if (const FileEntry *MainFile = SM.getFileEntryForID(SM.getMainFileID())) {
1721     auto FileAbbrev = std::make_shared<BitCodeAbbrev>();
1722     FileAbbrev->Add(BitCodeAbbrevOp(ORIGINAL_FILE));
1723     FileAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // File ID
1724     FileAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // File name
1725     unsigned FileAbbrevCode = Stream.EmitAbbrev(std::move(FileAbbrev));
1726 
1727     Record.clear();
1728     Record.push_back(ORIGINAL_FILE);
1729     Record.push_back(SM.getMainFileID().getOpaqueValue());
1730     EmitRecordWithPath(FileAbbrevCode, Record, MainFile->getName());
1731   }
1732 
1733   Record.clear();
1734   Record.push_back(SM.getMainFileID().getOpaqueValue());
1735   Stream.EmitRecord(ORIGINAL_FILE_ID, Record);
1736 
1737   // Original PCH directory
1738   if (!OutputFile.empty() && OutputFile != "-") {
1739     auto Abbrev = std::make_shared<BitCodeAbbrev>();
1740     Abbrev->Add(BitCodeAbbrevOp(ORIGINAL_PCH_DIR));
1741     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // File name
1742     unsigned AbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
1743 
1744     SmallString<128> OutputPath(OutputFile);
1745 
1746     SM.getFileManager().makeAbsolutePath(OutputPath);
1747     StringRef origDir = llvm::sys::path::parent_path(OutputPath);
1748 
1749     RecordData::value_type Record[] = {ORIGINAL_PCH_DIR};
1750     Stream.EmitRecordWithBlob(AbbrevCode, Record, origDir);
1751   }
1752 
1753   WriteInputFiles(Context.SourceMgr,
1754                   PP.getHeaderSearchInfo().getHeaderSearchOpts(),
1755                   PP.getLangOpts().Modules);
1756   Stream.ExitBlock();
1757 }
1758 
1759 namespace  {
1760 
1761 /// An input file.
1762 struct InputFileEntry {
1763   const FileEntry *File;
1764   bool IsSystemFile;
1765   bool IsTransient;
1766   bool BufferOverridden;
1767   bool IsTopLevelModuleMap;
1768   uint32_t ContentHash[2];
1769 };
1770 
1771 } // namespace
1772 
1773 void ASTWriter::WriteInputFiles(SourceManager &SourceMgr,
1774                                 HeaderSearchOptions &HSOpts,
1775                                 bool Modules) {
1776   using namespace llvm;
1777 
1778   Stream.EnterSubblock(INPUT_FILES_BLOCK_ID, 4);
1779 
1780   // Create input-file abbreviation.
1781   auto IFAbbrev = std::make_shared<BitCodeAbbrev>();
1782   IFAbbrev->Add(BitCodeAbbrevOp(INPUT_FILE));
1783   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ID
1784   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 12)); // Size
1785   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 32)); // Modification time
1786   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Overridden
1787   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Transient
1788   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Module map
1789   IFAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // File name
1790   unsigned IFAbbrevCode = Stream.EmitAbbrev(std::move(IFAbbrev));
1791 
1792   // Create input file hash abbreviation.
1793   auto IFHAbbrev = std::make_shared<BitCodeAbbrev>();
1794   IFHAbbrev->Add(BitCodeAbbrevOp(INPUT_FILE_HASH));
1795   IFHAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1796   IFHAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
1797   unsigned IFHAbbrevCode = Stream.EmitAbbrev(std::move(IFHAbbrev));
1798 
1799   // Get all ContentCache objects for files, sorted by whether the file is a
1800   // system one or not. System files go at the back, users files at the front.
1801   std::deque<InputFileEntry> SortedFiles;
1802   for (unsigned I = 1, N = SourceMgr.local_sloc_entry_size(); I != N; ++I) {
1803     // Get this source location entry.
1804     const SrcMgr::SLocEntry *SLoc = &SourceMgr.getLocalSLocEntry(I);
1805     assert(&SourceMgr.getSLocEntry(FileID::get(I)) == SLoc);
1806 
1807     // We only care about file entries that were not overridden.
1808     if (!SLoc->isFile())
1809       continue;
1810     const SrcMgr::FileInfo &File = SLoc->getFile();
1811     const SrcMgr::ContentCache *Cache = File.getContentCache();
1812     if (!Cache->OrigEntry)
1813       continue;
1814 
1815     InputFileEntry Entry;
1816     Entry.File = Cache->OrigEntry;
1817     Entry.IsSystemFile = isSystem(File.getFileCharacteristic());
1818     Entry.IsTransient = Cache->IsTransient;
1819     Entry.BufferOverridden = Cache->BufferOverridden;
1820     Entry.IsTopLevelModuleMap = isModuleMap(File.getFileCharacteristic()) &&
1821                                 File.getIncludeLoc().isInvalid();
1822 
1823     auto ContentHash = hash_code(-1);
1824     if (PP->getHeaderSearchInfo()
1825             .getHeaderSearchOpts()
1826             .ValidateASTInputFilesContent) {
1827       auto *MemBuff = Cache->getRawBuffer();
1828       if (MemBuff)
1829         ContentHash = hash_value(MemBuff->getBuffer());
1830       else
1831         // FIXME: The path should be taken from the FileEntryRef.
1832         PP->Diag(SourceLocation(), diag::err_module_unable_to_hash_content)
1833             << Entry.File->getName();
1834     }
1835     auto CH = llvm::APInt(64, ContentHash);
1836     Entry.ContentHash[0] =
1837         static_cast<uint32_t>(CH.getLoBits(32).getZExtValue());
1838     Entry.ContentHash[1] =
1839         static_cast<uint32_t>(CH.getHiBits(32).getZExtValue());
1840 
1841     if (Entry.IsSystemFile)
1842       SortedFiles.push_back(Entry);
1843     else
1844       SortedFiles.push_front(Entry);
1845   }
1846 
1847   unsigned UserFilesNum = 0;
1848   // Write out all of the input files.
1849   std::vector<uint64_t> InputFileOffsets;
1850   for (const auto &Entry : SortedFiles) {
1851     uint32_t &InputFileID = InputFileIDs[Entry.File];
1852     if (InputFileID != 0)
1853       continue; // already recorded this file.
1854 
1855     // Record this entry's offset.
1856     InputFileOffsets.push_back(Stream.GetCurrentBitNo());
1857 
1858     InputFileID = InputFileOffsets.size();
1859 
1860     if (!Entry.IsSystemFile)
1861       ++UserFilesNum;
1862 
1863     // Emit size/modification time for this file.
1864     // And whether this file was overridden.
1865     {
1866       RecordData::value_type Record[] = {
1867           INPUT_FILE,
1868           InputFileOffsets.size(),
1869           (uint64_t)Entry.File->getSize(),
1870           (uint64_t)getTimestampForOutput(Entry.File),
1871           Entry.BufferOverridden,
1872           Entry.IsTransient,
1873           Entry.IsTopLevelModuleMap};
1874 
1875       // FIXME: The path should be taken from the FileEntryRef.
1876       EmitRecordWithPath(IFAbbrevCode, Record, Entry.File->getName());
1877     }
1878 
1879     // Emit content hash for this file.
1880     {
1881       RecordData::value_type Record[] = {INPUT_FILE_HASH, Entry.ContentHash[0],
1882                                          Entry.ContentHash[1]};
1883       Stream.EmitRecordWithAbbrev(IFHAbbrevCode, Record);
1884     }
1885   }
1886 
1887   Stream.ExitBlock();
1888 
1889   // Create input file offsets abbreviation.
1890   auto OffsetsAbbrev = std::make_shared<BitCodeAbbrev>();
1891   OffsetsAbbrev->Add(BitCodeAbbrevOp(INPUT_FILE_OFFSETS));
1892   OffsetsAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // # input files
1893   OffsetsAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // # non-system
1894                                                                 //   input files
1895   OffsetsAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));   // Array
1896   unsigned OffsetsAbbrevCode = Stream.EmitAbbrev(std::move(OffsetsAbbrev));
1897 
1898   // Write input file offsets.
1899   RecordData::value_type Record[] = {INPUT_FILE_OFFSETS,
1900                                      InputFileOffsets.size(), UserFilesNum};
1901   Stream.EmitRecordWithBlob(OffsetsAbbrevCode, Record, bytes(InputFileOffsets));
1902 }
1903 
1904 //===----------------------------------------------------------------------===//
1905 // Source Manager Serialization
1906 //===----------------------------------------------------------------------===//
1907 
1908 /// Create an abbreviation for the SLocEntry that refers to a
1909 /// file.
1910 static unsigned CreateSLocFileAbbrev(llvm::BitstreamWriter &Stream) {
1911   using namespace llvm;
1912 
1913   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1914   Abbrev->Add(BitCodeAbbrevOp(SM_SLOC_FILE_ENTRY));
1915   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Offset
1916   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Include location
1917   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Characteristic
1918   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Line directives
1919   // FileEntry fields.
1920   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Input File ID
1921   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // NumCreatedFIDs
1922   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 24)); // FirstDeclIndex
1923   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // NumDecls
1924   return Stream.EmitAbbrev(std::move(Abbrev));
1925 }
1926 
1927 /// Create an abbreviation for the SLocEntry that refers to a
1928 /// buffer.
1929 static unsigned CreateSLocBufferAbbrev(llvm::BitstreamWriter &Stream) {
1930   using namespace llvm;
1931 
1932   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1933   Abbrev->Add(BitCodeAbbrevOp(SM_SLOC_BUFFER_ENTRY));
1934   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Offset
1935   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Include location
1936   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Characteristic
1937   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Line directives
1938   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Buffer name blob
1939   return Stream.EmitAbbrev(std::move(Abbrev));
1940 }
1941 
1942 /// Create an abbreviation for the SLocEntry that refers to a
1943 /// buffer's blob.
1944 static unsigned CreateSLocBufferBlobAbbrev(llvm::BitstreamWriter &Stream,
1945                                            bool Compressed) {
1946   using namespace llvm;
1947 
1948   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1949   Abbrev->Add(BitCodeAbbrevOp(Compressed ? SM_SLOC_BUFFER_BLOB_COMPRESSED
1950                                          : SM_SLOC_BUFFER_BLOB));
1951   if (Compressed)
1952     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Uncompressed size
1953   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Blob
1954   return Stream.EmitAbbrev(std::move(Abbrev));
1955 }
1956 
1957 /// Create an abbreviation for the SLocEntry that refers to a macro
1958 /// expansion.
1959 static unsigned CreateSLocExpansionAbbrev(llvm::BitstreamWriter &Stream) {
1960   using namespace llvm;
1961 
1962   auto Abbrev = std::make_shared<BitCodeAbbrev>();
1963   Abbrev->Add(BitCodeAbbrevOp(SM_SLOC_EXPANSION_ENTRY));
1964   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Offset
1965   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Spelling location
1966   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // Start location
1967   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // End location
1968   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Is token range
1969   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Token length
1970   return Stream.EmitAbbrev(std::move(Abbrev));
1971 }
1972 
1973 namespace {
1974 
1975   // Trait used for the on-disk hash table of header search information.
1976   class HeaderFileInfoTrait {
1977     ASTWriter &Writer;
1978 
1979     // Keep track of the framework names we've used during serialization.
1980     SmallVector<char, 128> FrameworkStringData;
1981     llvm::StringMap<unsigned> FrameworkNameOffset;
1982 
1983   public:
1984     HeaderFileInfoTrait(ASTWriter &Writer) : Writer(Writer) {}
1985 
1986     struct key_type {
1987       StringRef Filename;
1988       off_t Size;
1989       time_t ModTime;
1990     };
1991     using key_type_ref = const key_type &;
1992 
1993     using UnresolvedModule =
1994         llvm::PointerIntPair<Module *, 2, ModuleMap::ModuleHeaderRole>;
1995 
1996     struct data_type {
1997       const HeaderFileInfo &HFI;
1998       ArrayRef<ModuleMap::KnownHeader> KnownHeaders;
1999       UnresolvedModule Unresolved;
2000     };
2001     using data_type_ref = const data_type &;
2002 
2003     using hash_value_type = unsigned;
2004     using offset_type = unsigned;
2005 
2006     hash_value_type ComputeHash(key_type_ref key) {
2007       // The hash is based only on size/time of the file, so that the reader can
2008       // match even when symlinking or excess path elements ("foo/../", "../")
2009       // change the form of the name. However, complete path is still the key.
2010       return llvm::hash_combine(key.Size, key.ModTime);
2011     }
2012 
2013     std::pair<unsigned, unsigned>
2014     EmitKeyDataLength(raw_ostream& Out, key_type_ref key, data_type_ref Data) {
2015       using namespace llvm::support;
2016 
2017       endian::Writer LE(Out, little);
2018       unsigned KeyLen = key.Filename.size() + 1 + 8 + 8;
2019       LE.write<uint16_t>(KeyLen);
2020       unsigned DataLen = 1 + 2 + 4 + 4;
2021       for (auto ModInfo : Data.KnownHeaders)
2022         if (Writer.getLocalOrImportedSubmoduleID(ModInfo.getModule()))
2023           DataLen += 4;
2024       if (Data.Unresolved.getPointer())
2025         DataLen += 4;
2026       LE.write<uint8_t>(DataLen);
2027       return std::make_pair(KeyLen, DataLen);
2028     }
2029 
2030     void EmitKey(raw_ostream& Out, key_type_ref key, unsigned KeyLen) {
2031       using namespace llvm::support;
2032 
2033       endian::Writer LE(Out, little);
2034       LE.write<uint64_t>(key.Size);
2035       KeyLen -= 8;
2036       LE.write<uint64_t>(key.ModTime);
2037       KeyLen -= 8;
2038       Out.write(key.Filename.data(), KeyLen);
2039     }
2040 
2041     void EmitData(raw_ostream &Out, key_type_ref key,
2042                   data_type_ref Data, unsigned DataLen) {
2043       using namespace llvm::support;
2044 
2045       endian::Writer LE(Out, little);
2046       uint64_t Start = Out.tell(); (void)Start;
2047 
2048       unsigned char Flags = (Data.HFI.isImport << 5)
2049                           | (Data.HFI.isPragmaOnce << 4)
2050                           | (Data.HFI.DirInfo << 1)
2051                           | Data.HFI.IndexHeaderMapHeader;
2052       LE.write<uint8_t>(Flags);
2053       LE.write<uint16_t>(Data.HFI.NumIncludes);
2054 
2055       if (!Data.HFI.ControllingMacro)
2056         LE.write<uint32_t>(Data.HFI.ControllingMacroID);
2057       else
2058         LE.write<uint32_t>(Writer.getIdentifierRef(Data.HFI.ControllingMacro));
2059 
2060       unsigned Offset = 0;
2061       if (!Data.HFI.Framework.empty()) {
2062         // If this header refers into a framework, save the framework name.
2063         llvm::StringMap<unsigned>::iterator Pos
2064           = FrameworkNameOffset.find(Data.HFI.Framework);
2065         if (Pos == FrameworkNameOffset.end()) {
2066           Offset = FrameworkStringData.size() + 1;
2067           FrameworkStringData.append(Data.HFI.Framework.begin(),
2068                                      Data.HFI.Framework.end());
2069           FrameworkStringData.push_back(0);
2070 
2071           FrameworkNameOffset[Data.HFI.Framework] = Offset;
2072         } else
2073           Offset = Pos->second;
2074       }
2075       LE.write<uint32_t>(Offset);
2076 
2077       auto EmitModule = [&](Module *M, ModuleMap::ModuleHeaderRole Role) {
2078         if (uint32_t ModID = Writer.getLocalOrImportedSubmoduleID(M)) {
2079           uint32_t Value = (ModID << 2) | (unsigned)Role;
2080           assert((Value >> 2) == ModID && "overflow in header module info");
2081           LE.write<uint32_t>(Value);
2082         }
2083       };
2084 
2085       // FIXME: If the header is excluded, we should write out some
2086       // record of that fact.
2087       for (auto ModInfo : Data.KnownHeaders)
2088         EmitModule(ModInfo.getModule(), ModInfo.getRole());
2089       if (Data.Unresolved.getPointer())
2090         EmitModule(Data.Unresolved.getPointer(), Data.Unresolved.getInt());
2091 
2092       assert(Out.tell() - Start == DataLen && "Wrong data length");
2093     }
2094 
2095     const char *strings_begin() const { return FrameworkStringData.begin(); }
2096     const char *strings_end() const { return FrameworkStringData.end(); }
2097   };
2098 
2099 } // namespace
2100 
2101 /// Write the header search block for the list of files that
2102 ///
2103 /// \param HS The header search structure to save.
2104 void ASTWriter::WriteHeaderSearch(const HeaderSearch &HS) {
2105   HeaderFileInfoTrait GeneratorTrait(*this);
2106   llvm::OnDiskChainedHashTableGenerator<HeaderFileInfoTrait> Generator;
2107   SmallVector<const char *, 4> SavedStrings;
2108   unsigned NumHeaderSearchEntries = 0;
2109 
2110   // Find all unresolved headers for the current module. We generally will
2111   // have resolved them before we get here, but not necessarily: we might be
2112   // compiling a preprocessed module, where there is no requirement for the
2113   // original files to exist any more.
2114   const HeaderFileInfo Empty; // So we can take a reference.
2115   if (WritingModule) {
2116     llvm::SmallVector<Module *, 16> Worklist(1, WritingModule);
2117     while (!Worklist.empty()) {
2118       Module *M = Worklist.pop_back_val();
2119       if (!M->isAvailable())
2120         continue;
2121 
2122       // Map to disk files where possible, to pick up any missing stat
2123       // information. This also means we don't need to check the unresolved
2124       // headers list when emitting resolved headers in the first loop below.
2125       // FIXME: It'd be preferable to avoid doing this if we were given
2126       // sufficient stat information in the module map.
2127       HS.getModuleMap().resolveHeaderDirectives(M);
2128 
2129       // If the file didn't exist, we can still create a module if we were given
2130       // enough information in the module map.
2131       for (auto U : M->MissingHeaders) {
2132         // Check that we were given enough information to build a module
2133         // without this file existing on disk.
2134         if (!U.Size || (!U.ModTime && IncludeTimestamps)) {
2135           PP->Diag(U.FileNameLoc, diag::err_module_no_size_mtime_for_header)
2136             << WritingModule->getFullModuleName() << U.Size.hasValue()
2137             << U.FileName;
2138           continue;
2139         }
2140 
2141         // Form the effective relative pathname for the file.
2142         SmallString<128> Filename(M->Directory->getName());
2143         llvm::sys::path::append(Filename, U.FileName);
2144         PreparePathForOutput(Filename);
2145 
2146         StringRef FilenameDup = strdup(Filename.c_str());
2147         SavedStrings.push_back(FilenameDup.data());
2148 
2149         HeaderFileInfoTrait::key_type Key = {
2150           FilenameDup, *U.Size, IncludeTimestamps ? *U.ModTime : 0
2151         };
2152         HeaderFileInfoTrait::data_type Data = {
2153           Empty, {}, {M, ModuleMap::headerKindToRole(U.Kind)}
2154         };
2155         // FIXME: Deal with cases where there are multiple unresolved header
2156         // directives in different submodules for the same header.
2157         Generator.insert(Key, Data, GeneratorTrait);
2158         ++NumHeaderSearchEntries;
2159       }
2160 
2161       Worklist.append(M->submodule_begin(), M->submodule_end());
2162     }
2163   }
2164 
2165   SmallVector<const FileEntry *, 16> FilesByUID;
2166   HS.getFileMgr().GetUniqueIDMapping(FilesByUID);
2167 
2168   if (FilesByUID.size() > HS.header_file_size())
2169     FilesByUID.resize(HS.header_file_size());
2170 
2171   for (unsigned UID = 0, LastUID = FilesByUID.size(); UID != LastUID; ++UID) {
2172     const FileEntry *File = FilesByUID[UID];
2173     if (!File)
2174       continue;
2175 
2176     // Get the file info. This will load info from the external source if
2177     // necessary. Skip emitting this file if we have no information on it
2178     // as a header file (in which case HFI will be null) or if it hasn't
2179     // changed since it was loaded. Also skip it if it's for a modular header
2180     // from a different module; in that case, we rely on the module(s)
2181     // containing the header to provide this information.
2182     const HeaderFileInfo *HFI =
2183         HS.getExistingFileInfo(File, /*WantExternal*/!Chain);
2184     if (!HFI || (HFI->isModuleHeader && !HFI->isCompilingModuleHeader))
2185       continue;
2186 
2187     // Massage the file path into an appropriate form.
2188     StringRef Filename = File->getName();
2189     SmallString<128> FilenameTmp(Filename);
2190     if (PreparePathForOutput(FilenameTmp)) {
2191       // If we performed any translation on the file name at all, we need to
2192       // save this string, since the generator will refer to it later.
2193       Filename = StringRef(strdup(FilenameTmp.c_str()));
2194       SavedStrings.push_back(Filename.data());
2195     }
2196 
2197     HeaderFileInfoTrait::key_type Key = {
2198       Filename, File->getSize(), getTimestampForOutput(File)
2199     };
2200     HeaderFileInfoTrait::data_type Data = {
2201       *HFI, HS.getModuleMap().findAllModulesForHeader(File), {}
2202     };
2203     Generator.insert(Key, Data, GeneratorTrait);
2204     ++NumHeaderSearchEntries;
2205   }
2206 
2207   // Create the on-disk hash table in a buffer.
2208   SmallString<4096> TableData;
2209   uint32_t BucketOffset;
2210   {
2211     using namespace llvm::support;
2212 
2213     llvm::raw_svector_ostream Out(TableData);
2214     // Make sure that no bucket is at offset 0
2215     endian::write<uint32_t>(Out, 0, little);
2216     BucketOffset = Generator.Emit(Out, GeneratorTrait);
2217   }
2218 
2219   // Create a blob abbreviation
2220   using namespace llvm;
2221 
2222   auto Abbrev = std::make_shared<BitCodeAbbrev>();
2223   Abbrev->Add(BitCodeAbbrevOp(HEADER_SEARCH_TABLE));
2224   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
2225   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
2226   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
2227   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2228   unsigned TableAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2229 
2230   // Write the header search table
2231   RecordData::value_type Record[] = {HEADER_SEARCH_TABLE, BucketOffset,
2232                                      NumHeaderSearchEntries, TableData.size()};
2233   TableData.append(GeneratorTrait.strings_begin(),GeneratorTrait.strings_end());
2234   Stream.EmitRecordWithBlob(TableAbbrev, Record, TableData);
2235 
2236   // Free all of the strings we had to duplicate.
2237   for (unsigned I = 0, N = SavedStrings.size(); I != N; ++I)
2238     free(const_cast<char *>(SavedStrings[I]));
2239 }
2240 
2241 static void emitBlob(llvm::BitstreamWriter &Stream, StringRef Blob,
2242                      unsigned SLocBufferBlobCompressedAbbrv,
2243                      unsigned SLocBufferBlobAbbrv) {
2244   using RecordDataType = ASTWriter::RecordData::value_type;
2245 
2246   // Compress the buffer if possible. We expect that almost all PCM
2247   // consumers will not want its contents.
2248   SmallString<0> CompressedBuffer;
2249   if (llvm::zlib::isAvailable()) {
2250     llvm::Error E = llvm::zlib::compress(Blob.drop_back(1), CompressedBuffer);
2251     if (!E) {
2252       RecordDataType Record[] = {SM_SLOC_BUFFER_BLOB_COMPRESSED,
2253                                  Blob.size() - 1};
2254       Stream.EmitRecordWithBlob(SLocBufferBlobCompressedAbbrv, Record,
2255                                 CompressedBuffer);
2256       return;
2257     }
2258     llvm::consumeError(std::move(E));
2259   }
2260 
2261   RecordDataType Record[] = {SM_SLOC_BUFFER_BLOB};
2262   Stream.EmitRecordWithBlob(SLocBufferBlobAbbrv, Record, Blob);
2263 }
2264 
2265 /// Writes the block containing the serialized form of the
2266 /// source manager.
2267 ///
2268 /// TODO: We should probably use an on-disk hash table (stored in a
2269 /// blob), indexed based on the file name, so that we only create
2270 /// entries for files that we actually need. In the common case (no
2271 /// errors), we probably won't have to create file entries for any of
2272 /// the files in the AST.
2273 void ASTWriter::WriteSourceManagerBlock(SourceManager &SourceMgr,
2274                                         const Preprocessor &PP) {
2275   RecordData Record;
2276 
2277   // Enter the source manager block.
2278   Stream.EnterSubblock(SOURCE_MANAGER_BLOCK_ID, 4);
2279 
2280   // Abbreviations for the various kinds of source-location entries.
2281   unsigned SLocFileAbbrv = CreateSLocFileAbbrev(Stream);
2282   unsigned SLocBufferAbbrv = CreateSLocBufferAbbrev(Stream);
2283   unsigned SLocBufferBlobAbbrv = CreateSLocBufferBlobAbbrev(Stream, false);
2284   unsigned SLocBufferBlobCompressedAbbrv =
2285       CreateSLocBufferBlobAbbrev(Stream, true);
2286   unsigned SLocExpansionAbbrv = CreateSLocExpansionAbbrev(Stream);
2287 
2288   // Write out the source location entry table. We skip the first
2289   // entry, which is always the same dummy entry.
2290   std::vector<uint32_t> SLocEntryOffsets;
2291   RecordData PreloadSLocs;
2292   SLocEntryOffsets.reserve(SourceMgr.local_sloc_entry_size() - 1);
2293   for (unsigned I = 1, N = SourceMgr.local_sloc_entry_size();
2294        I != N; ++I) {
2295     // Get this source location entry.
2296     const SrcMgr::SLocEntry *SLoc = &SourceMgr.getLocalSLocEntry(I);
2297     FileID FID = FileID::get(I);
2298     assert(&SourceMgr.getSLocEntry(FID) == SLoc);
2299 
2300     // Record the offset of this source-location entry.
2301     SLocEntryOffsets.push_back(Stream.GetCurrentBitNo());
2302 
2303     // Figure out which record code to use.
2304     unsigned Code;
2305     if (SLoc->isFile()) {
2306       const SrcMgr::ContentCache *Cache = SLoc->getFile().getContentCache();
2307       if (Cache->OrigEntry) {
2308         Code = SM_SLOC_FILE_ENTRY;
2309       } else
2310         Code = SM_SLOC_BUFFER_ENTRY;
2311     } else
2312       Code = SM_SLOC_EXPANSION_ENTRY;
2313     Record.clear();
2314     Record.push_back(Code);
2315 
2316     // Starting offset of this entry within this module, so skip the dummy.
2317     Record.push_back(SLoc->getOffset() - 2);
2318     if (SLoc->isFile()) {
2319       const SrcMgr::FileInfo &File = SLoc->getFile();
2320       AddSourceLocation(File.getIncludeLoc(), Record);
2321       Record.push_back(File.getFileCharacteristic()); // FIXME: stable encoding
2322       Record.push_back(File.hasLineDirectives());
2323 
2324       const SrcMgr::ContentCache *Content = File.getContentCache();
2325       bool EmitBlob = false;
2326       if (Content->OrigEntry) {
2327         assert(Content->OrigEntry == Content->ContentsEntry &&
2328                "Writing to AST an overridden file is not supported");
2329 
2330         // The source location entry is a file. Emit input file ID.
2331         assert(InputFileIDs[Content->OrigEntry] != 0 && "Missed file entry");
2332         Record.push_back(InputFileIDs[Content->OrigEntry]);
2333 
2334         Record.push_back(File.NumCreatedFIDs);
2335 
2336         FileDeclIDsTy::iterator FDI = FileDeclIDs.find(FID);
2337         if (FDI != FileDeclIDs.end()) {
2338           Record.push_back(FDI->second->FirstDeclIndex);
2339           Record.push_back(FDI->second->DeclIDs.size());
2340         } else {
2341           Record.push_back(0);
2342           Record.push_back(0);
2343         }
2344 
2345         Stream.EmitRecordWithAbbrev(SLocFileAbbrv, Record);
2346 
2347         if (Content->BufferOverridden || Content->IsTransient)
2348           EmitBlob = true;
2349       } else {
2350         // The source location entry is a buffer. The blob associated
2351         // with this entry contains the contents of the buffer.
2352 
2353         // We add one to the size so that we capture the trailing NULL
2354         // that is required by llvm::MemoryBuffer::getMemBuffer (on
2355         // the reader side).
2356         const llvm::MemoryBuffer *Buffer =
2357             Content->getBuffer(PP.getDiagnostics(), PP.getFileManager());
2358         StringRef Name = Buffer->getBufferIdentifier();
2359         Stream.EmitRecordWithBlob(SLocBufferAbbrv, Record,
2360                                   StringRef(Name.data(), Name.size() + 1));
2361         EmitBlob = true;
2362 
2363         if (Name == "<built-in>")
2364           PreloadSLocs.push_back(SLocEntryOffsets.size());
2365       }
2366 
2367       if (EmitBlob) {
2368         // Include the implicit terminating null character in the on-disk buffer
2369         // if we're writing it uncompressed.
2370         const llvm::MemoryBuffer *Buffer =
2371             Content->getBuffer(PP.getDiagnostics(), PP.getFileManager());
2372         StringRef Blob(Buffer->getBufferStart(), Buffer->getBufferSize() + 1);
2373         emitBlob(Stream, Blob, SLocBufferBlobCompressedAbbrv,
2374                  SLocBufferBlobAbbrv);
2375       }
2376     } else {
2377       // The source location entry is a macro expansion.
2378       const SrcMgr::ExpansionInfo &Expansion = SLoc->getExpansion();
2379       AddSourceLocation(Expansion.getSpellingLoc(), Record);
2380       AddSourceLocation(Expansion.getExpansionLocStart(), Record);
2381       AddSourceLocation(Expansion.isMacroArgExpansion()
2382                             ? SourceLocation()
2383                             : Expansion.getExpansionLocEnd(),
2384                         Record);
2385       Record.push_back(Expansion.isExpansionTokenRange());
2386 
2387       // Compute the token length for this macro expansion.
2388       unsigned NextOffset = SourceMgr.getNextLocalOffset();
2389       if (I + 1 != N)
2390         NextOffset = SourceMgr.getLocalSLocEntry(I + 1).getOffset();
2391       Record.push_back(NextOffset - SLoc->getOffset() - 1);
2392       Stream.EmitRecordWithAbbrev(SLocExpansionAbbrv, Record);
2393     }
2394   }
2395 
2396   Stream.ExitBlock();
2397 
2398   if (SLocEntryOffsets.empty())
2399     return;
2400 
2401   // Write the source-location offsets table into the AST block. This
2402   // table is used for lazily loading source-location information.
2403   using namespace llvm;
2404 
2405   auto Abbrev = std::make_shared<BitCodeAbbrev>();
2406   Abbrev->Add(BitCodeAbbrevOp(SOURCE_LOCATION_OFFSETS));
2407   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 16)); // # of slocs
2408   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 16)); // total size
2409   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // offsets
2410   unsigned SLocOffsetsAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2411   {
2412     RecordData::value_type Record[] = {
2413         SOURCE_LOCATION_OFFSETS, SLocEntryOffsets.size(),
2414         SourceMgr.getNextLocalOffset() - 1 /* skip dummy */};
2415     Stream.EmitRecordWithBlob(SLocOffsetsAbbrev, Record,
2416                               bytes(SLocEntryOffsets));
2417   }
2418   // Write the source location entry preloads array, telling the AST
2419   // reader which source locations entries it should load eagerly.
2420   Stream.EmitRecord(SOURCE_LOCATION_PRELOADS, PreloadSLocs);
2421 
2422   // Write the line table. It depends on remapping working, so it must come
2423   // after the source location offsets.
2424   if (SourceMgr.hasLineTable()) {
2425     LineTableInfo &LineTable = SourceMgr.getLineTable();
2426 
2427     Record.clear();
2428 
2429     // Emit the needed file names.
2430     llvm::DenseMap<int, int> FilenameMap;
2431     FilenameMap[-1] = -1; // For unspecified filenames.
2432     for (const auto &L : LineTable) {
2433       if (L.first.ID < 0)
2434         continue;
2435       for (auto &LE : L.second) {
2436         if (FilenameMap.insert(std::make_pair(LE.FilenameID,
2437                                               FilenameMap.size() - 1)).second)
2438           AddPath(LineTable.getFilename(LE.FilenameID), Record);
2439       }
2440     }
2441     Record.push_back(0);
2442 
2443     // Emit the line entries
2444     for (const auto &L : LineTable) {
2445       // Only emit entries for local files.
2446       if (L.first.ID < 0)
2447         continue;
2448 
2449       // Emit the file ID
2450       Record.push_back(L.first.ID);
2451 
2452       // Emit the line entries
2453       Record.push_back(L.second.size());
2454       for (const auto &LE : L.second) {
2455         Record.push_back(LE.FileOffset);
2456         Record.push_back(LE.LineNo);
2457         Record.push_back(FilenameMap[LE.FilenameID]);
2458         Record.push_back((unsigned)LE.FileKind);
2459         Record.push_back(LE.IncludeOffset);
2460       }
2461     }
2462 
2463     Stream.EmitRecord(SOURCE_MANAGER_LINE_TABLE, Record);
2464   }
2465 }
2466 
2467 //===----------------------------------------------------------------------===//
2468 // Preprocessor Serialization
2469 //===----------------------------------------------------------------------===//
2470 
2471 static bool shouldIgnoreMacro(MacroDirective *MD, bool IsModule,
2472                               const Preprocessor &PP) {
2473   if (MacroInfo *MI = MD->getMacroInfo())
2474     if (MI->isBuiltinMacro())
2475       return true;
2476 
2477   if (IsModule) {
2478     SourceLocation Loc = MD->getLocation();
2479     if (Loc.isInvalid())
2480       return true;
2481     if (PP.getSourceManager().getFileID(Loc) == PP.getPredefinesFileID())
2482       return true;
2483   }
2484 
2485   return false;
2486 }
2487 
2488 /// Writes the block containing the serialized form of the
2489 /// preprocessor.
2490 void ASTWriter::WritePreprocessor(const Preprocessor &PP, bool IsModule) {
2491   PreprocessingRecord *PPRec = PP.getPreprocessingRecord();
2492   if (PPRec)
2493     WritePreprocessorDetail(*PPRec);
2494 
2495   RecordData Record;
2496   RecordData ModuleMacroRecord;
2497 
2498   // If the preprocessor __COUNTER__ value has been bumped, remember it.
2499   if (PP.getCounterValue() != 0) {
2500     RecordData::value_type Record[] = {PP.getCounterValue()};
2501     Stream.EmitRecord(PP_COUNTER_VALUE, Record);
2502   }
2503 
2504   if (PP.isRecordingPreamble() && PP.hasRecordedPreamble()) {
2505     assert(!IsModule);
2506     auto SkipInfo = PP.getPreambleSkipInfo();
2507     if (SkipInfo.hasValue()) {
2508       Record.push_back(true);
2509       AddSourceLocation(SkipInfo->HashTokenLoc, Record);
2510       AddSourceLocation(SkipInfo->IfTokenLoc, Record);
2511       Record.push_back(SkipInfo->FoundNonSkipPortion);
2512       Record.push_back(SkipInfo->FoundElse);
2513       AddSourceLocation(SkipInfo->ElseLoc, Record);
2514     } else {
2515       Record.push_back(false);
2516     }
2517     for (const auto &Cond : PP.getPreambleConditionalStack()) {
2518       AddSourceLocation(Cond.IfLoc, Record);
2519       Record.push_back(Cond.WasSkipping);
2520       Record.push_back(Cond.FoundNonSkip);
2521       Record.push_back(Cond.FoundElse);
2522     }
2523     Stream.EmitRecord(PP_CONDITIONAL_STACK, Record);
2524     Record.clear();
2525   }
2526 
2527   // Enter the preprocessor block.
2528   Stream.EnterSubblock(PREPROCESSOR_BLOCK_ID, 3);
2529 
2530   // If the AST file contains __DATE__ or __TIME__ emit a warning about this.
2531   // FIXME: Include a location for the use, and say which one was used.
2532   if (PP.SawDateOrTime())
2533     PP.Diag(SourceLocation(), diag::warn_module_uses_date_time) << IsModule;
2534 
2535   // Loop over all the macro directives that are live at the end of the file,
2536   // emitting each to the PP section.
2537 
2538   // Construct the list of identifiers with macro directives that need to be
2539   // serialized.
2540   SmallVector<const IdentifierInfo *, 128> MacroIdentifiers;
2541   for (auto &Id : PP.getIdentifierTable())
2542     if (Id.second->hadMacroDefinition() &&
2543         (!Id.second->isFromAST() ||
2544          Id.second->hasChangedSinceDeserialization()))
2545       MacroIdentifiers.push_back(Id.second);
2546   // Sort the set of macro definitions that need to be serialized by the
2547   // name of the macro, to provide a stable ordering.
2548   llvm::sort(MacroIdentifiers, llvm::deref<std::less<>>());
2549 
2550   // Emit the macro directives as a list and associate the offset with the
2551   // identifier they belong to.
2552   for (const IdentifierInfo *Name : MacroIdentifiers) {
2553     MacroDirective *MD = PP.getLocalMacroDirectiveHistory(Name);
2554     auto StartOffset = Stream.GetCurrentBitNo();
2555 
2556     // Emit the macro directives in reverse source order.
2557     for (; MD; MD = MD->getPrevious()) {
2558       // Once we hit an ignored macro, we're done: the rest of the chain
2559       // will all be ignored macros.
2560       if (shouldIgnoreMacro(MD, IsModule, PP))
2561         break;
2562 
2563       AddSourceLocation(MD->getLocation(), Record);
2564       Record.push_back(MD->getKind());
2565       if (auto *DefMD = dyn_cast<DefMacroDirective>(MD)) {
2566         Record.push_back(getMacroRef(DefMD->getInfo(), Name));
2567       } else if (auto *VisMD = dyn_cast<VisibilityMacroDirective>(MD)) {
2568         Record.push_back(VisMD->isPublic());
2569       }
2570     }
2571 
2572     // Write out any exported module macros.
2573     bool EmittedModuleMacros = false;
2574     // We write out exported module macros for PCH as well.
2575     auto Leafs = PP.getLeafModuleMacros(Name);
2576     SmallVector<ModuleMacro*, 8> Worklist(Leafs.begin(), Leafs.end());
2577     llvm::DenseMap<ModuleMacro*, unsigned> Visits;
2578     while (!Worklist.empty()) {
2579       auto *Macro = Worklist.pop_back_val();
2580 
2581       // Emit a record indicating this submodule exports this macro.
2582       ModuleMacroRecord.push_back(
2583           getSubmoduleID(Macro->getOwningModule()));
2584       ModuleMacroRecord.push_back(getMacroRef(Macro->getMacroInfo(), Name));
2585       for (auto *M : Macro->overrides())
2586         ModuleMacroRecord.push_back(getSubmoduleID(M->getOwningModule()));
2587 
2588       Stream.EmitRecord(PP_MODULE_MACRO, ModuleMacroRecord);
2589       ModuleMacroRecord.clear();
2590 
2591       // Enqueue overridden macros once we've visited all their ancestors.
2592       for (auto *M : Macro->overrides())
2593         if (++Visits[M] == M->getNumOverridingMacros())
2594           Worklist.push_back(M);
2595 
2596       EmittedModuleMacros = true;
2597     }
2598 
2599     if (Record.empty() && !EmittedModuleMacros)
2600       continue;
2601 
2602     IdentMacroDirectivesOffsetMap[Name] = StartOffset;
2603     Stream.EmitRecord(PP_MACRO_DIRECTIVE_HISTORY, Record);
2604     Record.clear();
2605   }
2606 
2607   /// Offsets of each of the macros into the bitstream, indexed by
2608   /// the local macro ID
2609   ///
2610   /// For each identifier that is associated with a macro, this map
2611   /// provides the offset into the bitstream where that macro is
2612   /// defined.
2613   std::vector<uint32_t> MacroOffsets;
2614 
2615   for (unsigned I = 0, N = MacroInfosToEmit.size(); I != N; ++I) {
2616     const IdentifierInfo *Name = MacroInfosToEmit[I].Name;
2617     MacroInfo *MI = MacroInfosToEmit[I].MI;
2618     MacroID ID = MacroInfosToEmit[I].ID;
2619 
2620     if (ID < FirstMacroID) {
2621       assert(0 && "Loaded MacroInfo entered MacroInfosToEmit ?");
2622       continue;
2623     }
2624 
2625     // Record the local offset of this macro.
2626     unsigned Index = ID - FirstMacroID;
2627     if (Index == MacroOffsets.size())
2628       MacroOffsets.push_back(Stream.GetCurrentBitNo());
2629     else {
2630       if (Index > MacroOffsets.size())
2631         MacroOffsets.resize(Index + 1);
2632 
2633       MacroOffsets[Index] = Stream.GetCurrentBitNo();
2634     }
2635 
2636     AddIdentifierRef(Name, Record);
2637     AddSourceLocation(MI->getDefinitionLoc(), Record);
2638     AddSourceLocation(MI->getDefinitionEndLoc(), Record);
2639     Record.push_back(MI->isUsed());
2640     Record.push_back(MI->isUsedForHeaderGuard());
2641     unsigned Code;
2642     if (MI->isObjectLike()) {
2643       Code = PP_MACRO_OBJECT_LIKE;
2644     } else {
2645       Code = PP_MACRO_FUNCTION_LIKE;
2646 
2647       Record.push_back(MI->isC99Varargs());
2648       Record.push_back(MI->isGNUVarargs());
2649       Record.push_back(MI->hasCommaPasting());
2650       Record.push_back(MI->getNumParams());
2651       for (const IdentifierInfo *Param : MI->params())
2652         AddIdentifierRef(Param, Record);
2653     }
2654 
2655     // If we have a detailed preprocessing record, record the macro definition
2656     // ID that corresponds to this macro.
2657     if (PPRec)
2658       Record.push_back(MacroDefinitions[PPRec->findMacroDefinition(MI)]);
2659 
2660     Stream.EmitRecord(Code, Record);
2661     Record.clear();
2662 
2663     // Emit the tokens array.
2664     for (unsigned TokNo = 0, e = MI->getNumTokens(); TokNo != e; ++TokNo) {
2665       // Note that we know that the preprocessor does not have any annotation
2666       // tokens in it because they are created by the parser, and thus can't
2667       // be in a macro definition.
2668       const Token &Tok = MI->getReplacementToken(TokNo);
2669       AddToken(Tok, Record);
2670       Stream.EmitRecord(PP_TOKEN, Record);
2671       Record.clear();
2672     }
2673     ++NumMacros;
2674   }
2675 
2676   Stream.ExitBlock();
2677 
2678   // Write the offsets table for macro IDs.
2679   using namespace llvm;
2680 
2681   auto Abbrev = std::make_shared<BitCodeAbbrev>();
2682   Abbrev->Add(BitCodeAbbrevOp(MACRO_OFFSET));
2683   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // # of macros
2684   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // first ID
2685   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2686 
2687   unsigned MacroOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2688   {
2689     RecordData::value_type Record[] = {MACRO_OFFSET, MacroOffsets.size(),
2690                                        FirstMacroID - NUM_PREDEF_MACRO_IDS};
2691     Stream.EmitRecordWithBlob(MacroOffsetAbbrev, Record, bytes(MacroOffsets));
2692   }
2693 }
2694 
2695 void ASTWriter::WritePreprocessorDetail(PreprocessingRecord &PPRec) {
2696   if (PPRec.local_begin() == PPRec.local_end())
2697     return;
2698 
2699   SmallVector<PPEntityOffset, 64> PreprocessedEntityOffsets;
2700 
2701   // Enter the preprocessor block.
2702   Stream.EnterSubblock(PREPROCESSOR_DETAIL_BLOCK_ID, 3);
2703 
2704   // If the preprocessor has a preprocessing record, emit it.
2705   unsigned NumPreprocessingRecords = 0;
2706   using namespace llvm;
2707 
2708   // Set up the abbreviation for
2709   unsigned InclusionAbbrev = 0;
2710   {
2711     auto Abbrev = std::make_shared<BitCodeAbbrev>();
2712     Abbrev->Add(BitCodeAbbrevOp(PPD_INCLUSION_DIRECTIVE));
2713     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // filename length
2714     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // in quotes
2715     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // kind
2716     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // imported module
2717     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2718     InclusionAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2719   }
2720 
2721   unsigned FirstPreprocessorEntityID
2722     = (Chain ? PPRec.getNumLoadedPreprocessedEntities() : 0)
2723     + NUM_PREDEF_PP_ENTITY_IDS;
2724   unsigned NextPreprocessorEntityID = FirstPreprocessorEntityID;
2725   RecordData Record;
2726   for (PreprocessingRecord::iterator E = PPRec.local_begin(),
2727                                   EEnd = PPRec.local_end();
2728        E != EEnd;
2729        (void)++E, ++NumPreprocessingRecords, ++NextPreprocessorEntityID) {
2730     Record.clear();
2731 
2732     PreprocessedEntityOffsets.push_back(
2733         PPEntityOffset((*E)->getSourceRange(), Stream.GetCurrentBitNo()));
2734 
2735     if (auto *MD = dyn_cast<MacroDefinitionRecord>(*E)) {
2736       // Record this macro definition's ID.
2737       MacroDefinitions[MD] = NextPreprocessorEntityID;
2738 
2739       AddIdentifierRef(MD->getName(), Record);
2740       Stream.EmitRecord(PPD_MACRO_DEFINITION, Record);
2741       continue;
2742     }
2743 
2744     if (auto *ME = dyn_cast<MacroExpansion>(*E)) {
2745       Record.push_back(ME->isBuiltinMacro());
2746       if (ME->isBuiltinMacro())
2747         AddIdentifierRef(ME->getName(), Record);
2748       else
2749         Record.push_back(MacroDefinitions[ME->getDefinition()]);
2750       Stream.EmitRecord(PPD_MACRO_EXPANSION, Record);
2751       continue;
2752     }
2753 
2754     if (auto *ID = dyn_cast<InclusionDirective>(*E)) {
2755       Record.push_back(PPD_INCLUSION_DIRECTIVE);
2756       Record.push_back(ID->getFileName().size());
2757       Record.push_back(ID->wasInQuotes());
2758       Record.push_back(static_cast<unsigned>(ID->getKind()));
2759       Record.push_back(ID->importedModule());
2760       SmallString<64> Buffer;
2761       Buffer += ID->getFileName();
2762       // Check that the FileEntry is not null because it was not resolved and
2763       // we create a PCH even with compiler errors.
2764       if (ID->getFile())
2765         Buffer += ID->getFile()->getName();
2766       Stream.EmitRecordWithBlob(InclusionAbbrev, Record, Buffer);
2767       continue;
2768     }
2769 
2770     llvm_unreachable("Unhandled PreprocessedEntity in ASTWriter");
2771   }
2772   Stream.ExitBlock();
2773 
2774   // Write the offsets table for the preprocessing record.
2775   if (NumPreprocessingRecords > 0) {
2776     assert(PreprocessedEntityOffsets.size() == NumPreprocessingRecords);
2777 
2778     // Write the offsets table for identifier IDs.
2779     using namespace llvm;
2780 
2781     auto Abbrev = std::make_shared<BitCodeAbbrev>();
2782     Abbrev->Add(BitCodeAbbrevOp(PPD_ENTITIES_OFFSETS));
2783     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // first pp entity
2784     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2785     unsigned PPEOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2786 
2787     RecordData::value_type Record[] = {PPD_ENTITIES_OFFSETS,
2788                                        FirstPreprocessorEntityID -
2789                                            NUM_PREDEF_PP_ENTITY_IDS};
2790     Stream.EmitRecordWithBlob(PPEOffsetAbbrev, Record,
2791                               bytes(PreprocessedEntityOffsets));
2792   }
2793 
2794   // Write the skipped region table for the preprocessing record.
2795   ArrayRef<SourceRange> SkippedRanges = PPRec.getSkippedRanges();
2796   if (SkippedRanges.size() > 0) {
2797     std::vector<PPSkippedRange> SerializedSkippedRanges;
2798     SerializedSkippedRanges.reserve(SkippedRanges.size());
2799     for (auto const& Range : SkippedRanges)
2800       SerializedSkippedRanges.emplace_back(Range);
2801 
2802     using namespace llvm;
2803     auto Abbrev = std::make_shared<BitCodeAbbrev>();
2804     Abbrev->Add(BitCodeAbbrevOp(PPD_SKIPPED_RANGES));
2805     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
2806     unsigned PPESkippedRangeAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2807 
2808     Record.clear();
2809     Record.push_back(PPD_SKIPPED_RANGES);
2810     Stream.EmitRecordWithBlob(PPESkippedRangeAbbrev, Record,
2811                               bytes(SerializedSkippedRanges));
2812   }
2813 }
2814 
2815 unsigned ASTWriter::getLocalOrImportedSubmoduleID(Module *Mod) {
2816   if (!Mod)
2817     return 0;
2818 
2819   llvm::DenseMap<Module *, unsigned>::iterator Known = SubmoduleIDs.find(Mod);
2820   if (Known != SubmoduleIDs.end())
2821     return Known->second;
2822 
2823   auto *Top = Mod->getTopLevelModule();
2824   if (Top != WritingModule &&
2825       (getLangOpts().CompilingPCH ||
2826        !Top->fullModuleNameIs(StringRef(getLangOpts().CurrentModule))))
2827     return 0;
2828 
2829   return SubmoduleIDs[Mod] = NextSubmoduleID++;
2830 }
2831 
2832 unsigned ASTWriter::getSubmoduleID(Module *Mod) {
2833   // FIXME: This can easily happen, if we have a reference to a submodule that
2834   // did not result in us loading a module file for that submodule. For
2835   // instance, a cross-top-level-module 'conflict' declaration will hit this.
2836   unsigned ID = getLocalOrImportedSubmoduleID(Mod);
2837   assert((ID || !Mod) &&
2838          "asked for module ID for non-local, non-imported module");
2839   return ID;
2840 }
2841 
2842 /// Compute the number of modules within the given tree (including the
2843 /// given module).
2844 static unsigned getNumberOfModules(Module *Mod) {
2845   unsigned ChildModules = 0;
2846   for (auto Sub = Mod->submodule_begin(), SubEnd = Mod->submodule_end();
2847        Sub != SubEnd; ++Sub)
2848     ChildModules += getNumberOfModules(*Sub);
2849 
2850   return ChildModules + 1;
2851 }
2852 
2853 void ASTWriter::WriteSubmodules(Module *WritingModule) {
2854   // Enter the submodule description block.
2855   Stream.EnterSubblock(SUBMODULE_BLOCK_ID, /*bits for abbreviations*/5);
2856 
2857   // Write the abbreviations needed for the submodules block.
2858   using namespace llvm;
2859 
2860   auto Abbrev = std::make_shared<BitCodeAbbrev>();
2861   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_DEFINITION));
2862   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ID
2863   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Parent
2864   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // Kind
2865   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFramework
2866   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsExplicit
2867   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsSystem
2868   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsExternC
2869   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InferSubmodules...
2870   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InferExplicit...
2871   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // InferExportWild...
2872   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ConfigMacrosExh...
2873   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ModuleMapIsPriv...
2874   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2875   unsigned DefinitionAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2876 
2877   Abbrev = std::make_shared<BitCodeAbbrev>();
2878   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_UMBRELLA_HEADER));
2879   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2880   unsigned UmbrellaAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2881 
2882   Abbrev = std::make_shared<BitCodeAbbrev>();
2883   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_HEADER));
2884   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2885   unsigned HeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2886 
2887   Abbrev = std::make_shared<BitCodeAbbrev>();
2888   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_TOPHEADER));
2889   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2890   unsigned TopHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2891 
2892   Abbrev = std::make_shared<BitCodeAbbrev>();
2893   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_UMBRELLA_DIR));
2894   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2895   unsigned UmbrellaDirAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2896 
2897   Abbrev = std::make_shared<BitCodeAbbrev>();
2898   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_REQUIRES));
2899   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // State
2900   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));     // Feature
2901   unsigned RequiresAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2902 
2903   Abbrev = std::make_shared<BitCodeAbbrev>();
2904   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_EXCLUDED_HEADER));
2905   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2906   unsigned ExcludedHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2907 
2908   Abbrev = std::make_shared<BitCodeAbbrev>();
2909   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_TEXTUAL_HEADER));
2910   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2911   unsigned TextualHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2912 
2913   Abbrev = std::make_shared<BitCodeAbbrev>();
2914   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_PRIVATE_HEADER));
2915   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2916   unsigned PrivateHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2917 
2918   Abbrev = std::make_shared<BitCodeAbbrev>();
2919   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_PRIVATE_TEXTUAL_HEADER));
2920   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
2921   unsigned PrivateTextualHeaderAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2922 
2923   Abbrev = std::make_shared<BitCodeAbbrev>();
2924   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_LINK_LIBRARY));
2925   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsFramework
2926   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));     // Name
2927   unsigned LinkLibraryAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2928 
2929   Abbrev = std::make_shared<BitCodeAbbrev>();
2930   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_CONFIG_MACRO));
2931   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));    // Macro name
2932   unsigned ConfigMacroAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2933 
2934   Abbrev = std::make_shared<BitCodeAbbrev>();
2935   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_CONFLICT));
2936   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));  // Other module
2937   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));    // Message
2938   unsigned ConflictAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2939 
2940   Abbrev = std::make_shared<BitCodeAbbrev>();
2941   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_EXPORT_AS));
2942   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));    // Macro name
2943   unsigned ExportAsAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
2944 
2945   // Write the submodule metadata block.
2946   RecordData::value_type Record[] = {
2947       getNumberOfModules(WritingModule),
2948       FirstSubmoduleID - NUM_PREDEF_SUBMODULE_IDS};
2949   Stream.EmitRecord(SUBMODULE_METADATA, Record);
2950 
2951   // Write all of the submodules.
2952   std::queue<Module *> Q;
2953   Q.push(WritingModule);
2954   while (!Q.empty()) {
2955     Module *Mod = Q.front();
2956     Q.pop();
2957     unsigned ID = getSubmoduleID(Mod);
2958 
2959     uint64_t ParentID = 0;
2960     if (Mod->Parent) {
2961       assert(SubmoduleIDs[Mod->Parent] && "Submodule parent not written?");
2962       ParentID = SubmoduleIDs[Mod->Parent];
2963     }
2964 
2965     // Emit the definition of the block.
2966     {
2967       RecordData::value_type Record[] = {SUBMODULE_DEFINITION,
2968                                          ID,
2969                                          ParentID,
2970                                          (RecordData::value_type)Mod->Kind,
2971                                          Mod->IsFramework,
2972                                          Mod->IsExplicit,
2973                                          Mod->IsSystem,
2974                                          Mod->IsExternC,
2975                                          Mod->InferSubmodules,
2976                                          Mod->InferExplicitSubmodules,
2977                                          Mod->InferExportWildcard,
2978                                          Mod->ConfigMacrosExhaustive,
2979                                          Mod->ModuleMapIsPrivate};
2980       Stream.EmitRecordWithBlob(DefinitionAbbrev, Record, Mod->Name);
2981     }
2982 
2983     // Emit the requirements.
2984     for (const auto &R : Mod->Requirements) {
2985       RecordData::value_type Record[] = {SUBMODULE_REQUIRES, R.second};
2986       Stream.EmitRecordWithBlob(RequiresAbbrev, Record, R.first);
2987     }
2988 
2989     // Emit the umbrella header, if there is one.
2990     if (auto UmbrellaHeader = Mod->getUmbrellaHeader()) {
2991       RecordData::value_type Record[] = {SUBMODULE_UMBRELLA_HEADER};
2992       Stream.EmitRecordWithBlob(UmbrellaAbbrev, Record,
2993                                 UmbrellaHeader.NameAsWritten);
2994     } else if (auto UmbrellaDir = Mod->getUmbrellaDir()) {
2995       RecordData::value_type Record[] = {SUBMODULE_UMBRELLA_DIR};
2996       Stream.EmitRecordWithBlob(UmbrellaDirAbbrev, Record,
2997                                 UmbrellaDir.NameAsWritten);
2998     }
2999 
3000     // Emit the headers.
3001     struct {
3002       unsigned RecordKind;
3003       unsigned Abbrev;
3004       Module::HeaderKind HeaderKind;
3005     } HeaderLists[] = {
3006       {SUBMODULE_HEADER, HeaderAbbrev, Module::HK_Normal},
3007       {SUBMODULE_TEXTUAL_HEADER, TextualHeaderAbbrev, Module::HK_Textual},
3008       {SUBMODULE_PRIVATE_HEADER, PrivateHeaderAbbrev, Module::HK_Private},
3009       {SUBMODULE_PRIVATE_TEXTUAL_HEADER, PrivateTextualHeaderAbbrev,
3010         Module::HK_PrivateTextual},
3011       {SUBMODULE_EXCLUDED_HEADER, ExcludedHeaderAbbrev, Module::HK_Excluded}
3012     };
3013     for (auto &HL : HeaderLists) {
3014       RecordData::value_type Record[] = {HL.RecordKind};
3015       for (auto &H : Mod->Headers[HL.HeaderKind])
3016         Stream.EmitRecordWithBlob(HL.Abbrev, Record, H.NameAsWritten);
3017     }
3018 
3019     // Emit the top headers.
3020     {
3021       auto TopHeaders = Mod->getTopHeaders(PP->getFileManager());
3022       RecordData::value_type Record[] = {SUBMODULE_TOPHEADER};
3023       for (auto *H : TopHeaders)
3024         Stream.EmitRecordWithBlob(TopHeaderAbbrev, Record, H->getName());
3025     }
3026 
3027     // Emit the imports.
3028     if (!Mod->Imports.empty()) {
3029       RecordData Record;
3030       for (auto *I : Mod->Imports)
3031         Record.push_back(getSubmoduleID(I));
3032       Stream.EmitRecord(SUBMODULE_IMPORTS, Record);
3033     }
3034 
3035     // Emit the exports.
3036     if (!Mod->Exports.empty()) {
3037       RecordData Record;
3038       for (const auto &E : Mod->Exports) {
3039         // FIXME: This may fail; we don't require that all exported modules
3040         // are local or imported.
3041         Record.push_back(getSubmoduleID(E.getPointer()));
3042         Record.push_back(E.getInt());
3043       }
3044       Stream.EmitRecord(SUBMODULE_EXPORTS, Record);
3045     }
3046 
3047     //FIXME: How do we emit the 'use'd modules?  They may not be submodules.
3048     // Might be unnecessary as use declarations are only used to build the
3049     // module itself.
3050 
3051     // Emit the link libraries.
3052     for (const auto &LL : Mod->LinkLibraries) {
3053       RecordData::value_type Record[] = {SUBMODULE_LINK_LIBRARY,
3054                                          LL.IsFramework};
3055       Stream.EmitRecordWithBlob(LinkLibraryAbbrev, Record, LL.Library);
3056     }
3057 
3058     // Emit the conflicts.
3059     for (const auto &C : Mod->Conflicts) {
3060       // FIXME: This may fail; we don't require that all conflicting modules
3061       // are local or imported.
3062       RecordData::value_type Record[] = {SUBMODULE_CONFLICT,
3063                                          getSubmoduleID(C.Other)};
3064       Stream.EmitRecordWithBlob(ConflictAbbrev, Record, C.Message);
3065     }
3066 
3067     // Emit the configuration macros.
3068     for (const auto &CM : Mod->ConfigMacros) {
3069       RecordData::value_type Record[] = {SUBMODULE_CONFIG_MACRO};
3070       Stream.EmitRecordWithBlob(ConfigMacroAbbrev, Record, CM);
3071     }
3072 
3073     // Emit the initializers, if any.
3074     RecordData Inits;
3075     for (Decl *D : Context->getModuleInitializers(Mod))
3076       Inits.push_back(GetDeclRef(D));
3077     if (!Inits.empty())
3078       Stream.EmitRecord(SUBMODULE_INITIALIZERS, Inits);
3079 
3080     // Emit the name of the re-exported module, if any.
3081     if (!Mod->ExportAsModule.empty()) {
3082       RecordData::value_type Record[] = {SUBMODULE_EXPORT_AS};
3083       Stream.EmitRecordWithBlob(ExportAsAbbrev, Record, Mod->ExportAsModule);
3084     }
3085 
3086     // Queue up the submodules of this module.
3087     for (auto *M : Mod->submodules())
3088       Q.push(M);
3089   }
3090 
3091   Stream.ExitBlock();
3092 
3093   assert((NextSubmoduleID - FirstSubmoduleID ==
3094           getNumberOfModules(WritingModule)) &&
3095          "Wrong # of submodules; found a reference to a non-local, "
3096          "non-imported submodule?");
3097 }
3098 
3099 void ASTWriter::WritePragmaDiagnosticMappings(const DiagnosticsEngine &Diag,
3100                                               bool isModule) {
3101   llvm::SmallDenseMap<const DiagnosticsEngine::DiagState *, unsigned, 64>
3102       DiagStateIDMap;
3103   unsigned CurrID = 0;
3104   RecordData Record;
3105 
3106   auto EncodeDiagStateFlags =
3107       [](const DiagnosticsEngine::DiagState *DS) -> unsigned {
3108     unsigned Result = (unsigned)DS->ExtBehavior;
3109     for (unsigned Val :
3110          {(unsigned)DS->IgnoreAllWarnings, (unsigned)DS->EnableAllWarnings,
3111           (unsigned)DS->WarningsAsErrors, (unsigned)DS->ErrorsAsFatal,
3112           (unsigned)DS->SuppressSystemWarnings})
3113       Result = (Result << 1) | Val;
3114     return Result;
3115   };
3116 
3117   unsigned Flags = EncodeDiagStateFlags(Diag.DiagStatesByLoc.FirstDiagState);
3118   Record.push_back(Flags);
3119 
3120   auto AddDiagState = [&](const DiagnosticsEngine::DiagState *State,
3121                           bool IncludeNonPragmaStates) {
3122     // Ensure that the diagnostic state wasn't modified since it was created.
3123     // We will not correctly round-trip this information otherwise.
3124     assert(Flags == EncodeDiagStateFlags(State) &&
3125            "diag state flags vary in single AST file");
3126 
3127     unsigned &DiagStateID = DiagStateIDMap[State];
3128     Record.push_back(DiagStateID);
3129 
3130     if (DiagStateID == 0) {
3131       DiagStateID = ++CurrID;
3132 
3133       // Add a placeholder for the number of mappings.
3134       auto SizeIdx = Record.size();
3135       Record.emplace_back();
3136       for (const auto &I : *State) {
3137         if (I.second.isPragma() || IncludeNonPragmaStates) {
3138           Record.push_back(I.first);
3139           Record.push_back(I.second.serialize());
3140         }
3141       }
3142       // Update the placeholder.
3143       Record[SizeIdx] = (Record.size() - SizeIdx) / 2;
3144     }
3145   };
3146 
3147   AddDiagState(Diag.DiagStatesByLoc.FirstDiagState, isModule);
3148 
3149   // Reserve a spot for the number of locations with state transitions.
3150   auto NumLocationsIdx = Record.size();
3151   Record.emplace_back();
3152 
3153   // Emit the state transitions.
3154   unsigned NumLocations = 0;
3155   for (auto &FileIDAndFile : Diag.DiagStatesByLoc.Files) {
3156     if (!FileIDAndFile.first.isValid() ||
3157         !FileIDAndFile.second.HasLocalTransitions)
3158       continue;
3159     ++NumLocations;
3160 
3161     SourceLocation Loc = Diag.SourceMgr->getComposedLoc(FileIDAndFile.first, 0);
3162     assert(!Loc.isInvalid() && "start loc for valid FileID is invalid");
3163     AddSourceLocation(Loc, Record);
3164 
3165     Record.push_back(FileIDAndFile.second.StateTransitions.size());
3166     for (auto &StatePoint : FileIDAndFile.second.StateTransitions) {
3167       Record.push_back(StatePoint.Offset);
3168       AddDiagState(StatePoint.State, false);
3169     }
3170   }
3171 
3172   // Backpatch the number of locations.
3173   Record[NumLocationsIdx] = NumLocations;
3174 
3175   // Emit CurDiagStateLoc.  Do it last in order to match source order.
3176   //
3177   // This also protects against a hypothetical corner case with simulating
3178   // -Werror settings for implicit modules in the ASTReader, where reading
3179   // CurDiagState out of context could change whether warning pragmas are
3180   // treated as errors.
3181   AddSourceLocation(Diag.DiagStatesByLoc.CurDiagStateLoc, Record);
3182   AddDiagState(Diag.DiagStatesByLoc.CurDiagState, false);
3183 
3184   Stream.EmitRecord(DIAG_PRAGMA_MAPPINGS, Record);
3185 }
3186 
3187 //===----------------------------------------------------------------------===//
3188 // Type Serialization
3189 //===----------------------------------------------------------------------===//
3190 
3191 /// Write the representation of a type to the AST stream.
3192 void ASTWriter::WriteType(QualType T) {
3193   TypeIdx &IdxRef = TypeIdxs[T];
3194   if (IdxRef.getIndex() == 0) // we haven't seen this type before.
3195     IdxRef = TypeIdx(NextTypeID++);
3196   TypeIdx Idx = IdxRef;
3197 
3198   assert(Idx.getIndex() >= FirstTypeID && "Re-writing a type from a prior AST");
3199 
3200   RecordData Record;
3201 
3202   // Emit the type's representation.
3203   ASTTypeWriter W(*this, Record);
3204   W.Visit(T);
3205   uint64_t Offset = W.Emit();
3206 
3207   // Record the offset for this type.
3208   unsigned Index = Idx.getIndex() - FirstTypeID;
3209   if (TypeOffsets.size() == Index)
3210     TypeOffsets.push_back(Offset);
3211   else if (TypeOffsets.size() < Index) {
3212     TypeOffsets.resize(Index + 1);
3213     TypeOffsets[Index] = Offset;
3214   } else {
3215     llvm_unreachable("Types emitted in wrong order");
3216   }
3217 }
3218 
3219 //===----------------------------------------------------------------------===//
3220 // Declaration Serialization
3221 //===----------------------------------------------------------------------===//
3222 
3223 /// Write the block containing all of the declaration IDs
3224 /// lexically declared within the given DeclContext.
3225 ///
3226 /// \returns the offset of the DECL_CONTEXT_LEXICAL block within the
3227 /// bitstream, or 0 if no block was written.
3228 uint64_t ASTWriter::WriteDeclContextLexicalBlock(ASTContext &Context,
3229                                                  DeclContext *DC) {
3230   if (DC->decls_empty())
3231     return 0;
3232 
3233   uint64_t Offset = Stream.GetCurrentBitNo();
3234   SmallVector<uint32_t, 128> KindDeclPairs;
3235   for (const auto *D : DC->decls()) {
3236     KindDeclPairs.push_back(D->getKind());
3237     KindDeclPairs.push_back(GetDeclRef(D));
3238   }
3239 
3240   ++NumLexicalDeclContexts;
3241   RecordData::value_type Record[] = {DECL_CONTEXT_LEXICAL};
3242   Stream.EmitRecordWithBlob(DeclContextLexicalAbbrev, Record,
3243                             bytes(KindDeclPairs));
3244   return Offset;
3245 }
3246 
3247 void ASTWriter::WriteTypeDeclOffsets() {
3248   using namespace llvm;
3249 
3250   // Write the type offsets array
3251   auto Abbrev = std::make_shared<BitCodeAbbrev>();
3252   Abbrev->Add(BitCodeAbbrevOp(TYPE_OFFSET));
3253   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // # of types
3254   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // base type index
3255   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // types block
3256   unsigned TypeOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3257   {
3258     RecordData::value_type Record[] = {TYPE_OFFSET, TypeOffsets.size(),
3259                                        FirstTypeID - NUM_PREDEF_TYPE_IDS};
3260     Stream.EmitRecordWithBlob(TypeOffsetAbbrev, Record, bytes(TypeOffsets));
3261   }
3262 
3263   // Write the declaration offsets array
3264   Abbrev = std::make_shared<BitCodeAbbrev>();
3265   Abbrev->Add(BitCodeAbbrevOp(DECL_OFFSET));
3266   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // # of declarations
3267   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // base decl ID
3268   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // declarations block
3269   unsigned DeclOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3270   {
3271     RecordData::value_type Record[] = {DECL_OFFSET, DeclOffsets.size(),
3272                                        FirstDeclID - NUM_PREDEF_DECL_IDS};
3273     Stream.EmitRecordWithBlob(DeclOffsetAbbrev, Record, bytes(DeclOffsets));
3274   }
3275 }
3276 
3277 void ASTWriter::WriteFileDeclIDsMap() {
3278   using namespace llvm;
3279 
3280   SmallVector<std::pair<FileID, DeclIDInFileInfo *>, 64> SortedFileDeclIDs(
3281       FileDeclIDs.begin(), FileDeclIDs.end());
3282   llvm::sort(SortedFileDeclIDs, llvm::less_first());
3283 
3284   // Join the vectors of DeclIDs from all files.
3285   SmallVector<DeclID, 256> FileGroupedDeclIDs;
3286   for (auto &FileDeclEntry : SortedFileDeclIDs) {
3287     DeclIDInFileInfo &Info = *FileDeclEntry.second;
3288     Info.FirstDeclIndex = FileGroupedDeclIDs.size();
3289     for (auto &LocDeclEntry : Info.DeclIDs)
3290       FileGroupedDeclIDs.push_back(LocDeclEntry.second);
3291   }
3292 
3293   auto Abbrev = std::make_shared<BitCodeAbbrev>();
3294   Abbrev->Add(BitCodeAbbrevOp(FILE_SORTED_DECLS));
3295   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
3296   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3297   unsigned AbbrevCode = Stream.EmitAbbrev(std::move(Abbrev));
3298   RecordData::value_type Record[] = {FILE_SORTED_DECLS,
3299                                      FileGroupedDeclIDs.size()};
3300   Stream.EmitRecordWithBlob(AbbrevCode, Record, bytes(FileGroupedDeclIDs));
3301 }
3302 
3303 void ASTWriter::WriteComments() {
3304   Stream.EnterSubblock(COMMENTS_BLOCK_ID, 3);
3305   auto _ = llvm::make_scope_exit([this] { Stream.ExitBlock(); });
3306   if (!PP->getPreprocessorOpts().WriteCommentListToPCH)
3307     return;
3308   RecordData Record;
3309   for (const auto &FO : Context->Comments.OrderedComments) {
3310     for (const auto &OC : FO.second) {
3311       const RawComment *I = OC.second;
3312       Record.clear();
3313       AddSourceRange(I->getSourceRange(), Record);
3314       Record.push_back(I->getKind());
3315       Record.push_back(I->isTrailingComment());
3316       Record.push_back(I->isAlmostTrailingComment());
3317       Stream.EmitRecord(COMMENTS_RAW_COMMENT, Record);
3318     }
3319   }
3320 }
3321 
3322 //===----------------------------------------------------------------------===//
3323 // Global Method Pool and Selector Serialization
3324 //===----------------------------------------------------------------------===//
3325 
3326 namespace {
3327 
3328 // Trait used for the on-disk hash table used in the method pool.
3329 class ASTMethodPoolTrait {
3330   ASTWriter &Writer;
3331 
3332 public:
3333   using key_type = Selector;
3334   using key_type_ref = key_type;
3335 
3336   struct data_type {
3337     SelectorID ID;
3338     ObjCMethodList Instance, Factory;
3339   };
3340   using data_type_ref = const data_type &;
3341 
3342   using hash_value_type = unsigned;
3343   using offset_type = unsigned;
3344 
3345   explicit ASTMethodPoolTrait(ASTWriter &Writer) : Writer(Writer) {}
3346 
3347   static hash_value_type ComputeHash(Selector Sel) {
3348     return serialization::ComputeHash(Sel);
3349   }
3350 
3351   std::pair<unsigned, unsigned>
3352     EmitKeyDataLength(raw_ostream& Out, Selector Sel,
3353                       data_type_ref Methods) {
3354     using namespace llvm::support;
3355 
3356     endian::Writer LE(Out, little);
3357     unsigned KeyLen = 2 + (Sel.getNumArgs()? Sel.getNumArgs() * 4 : 4);
3358     LE.write<uint16_t>(KeyLen);
3359     unsigned DataLen = 4 + 2 + 2; // 2 bytes for each of the method counts
3360     for (const ObjCMethodList *Method = &Methods.Instance; Method;
3361          Method = Method->getNext())
3362       if (Method->getMethod())
3363         DataLen += 4;
3364     for (const ObjCMethodList *Method = &Methods.Factory; Method;
3365          Method = Method->getNext())
3366       if (Method->getMethod())
3367         DataLen += 4;
3368     LE.write<uint16_t>(DataLen);
3369     return std::make_pair(KeyLen, DataLen);
3370   }
3371 
3372   void EmitKey(raw_ostream& Out, Selector Sel, unsigned) {
3373     using namespace llvm::support;
3374 
3375     endian::Writer LE(Out, little);
3376     uint64_t Start = Out.tell();
3377     assert((Start >> 32) == 0 && "Selector key offset too large");
3378     Writer.SetSelectorOffset(Sel, Start);
3379     unsigned N = Sel.getNumArgs();
3380     LE.write<uint16_t>(N);
3381     if (N == 0)
3382       N = 1;
3383     for (unsigned I = 0; I != N; ++I)
3384       LE.write<uint32_t>(
3385           Writer.getIdentifierRef(Sel.getIdentifierInfoForSlot(I)));
3386   }
3387 
3388   void EmitData(raw_ostream& Out, key_type_ref,
3389                 data_type_ref Methods, unsigned DataLen) {
3390     using namespace llvm::support;
3391 
3392     endian::Writer LE(Out, little);
3393     uint64_t Start = Out.tell(); (void)Start;
3394     LE.write<uint32_t>(Methods.ID);
3395     unsigned NumInstanceMethods = 0;
3396     for (const ObjCMethodList *Method = &Methods.Instance; Method;
3397          Method = Method->getNext())
3398       if (Method->getMethod())
3399         ++NumInstanceMethods;
3400 
3401     unsigned NumFactoryMethods = 0;
3402     for (const ObjCMethodList *Method = &Methods.Factory; Method;
3403          Method = Method->getNext())
3404       if (Method->getMethod())
3405         ++NumFactoryMethods;
3406 
3407     unsigned InstanceBits = Methods.Instance.getBits();
3408     assert(InstanceBits < 4);
3409     unsigned InstanceHasMoreThanOneDeclBit =
3410         Methods.Instance.hasMoreThanOneDecl();
3411     unsigned FullInstanceBits = (NumInstanceMethods << 3) |
3412                                 (InstanceHasMoreThanOneDeclBit << 2) |
3413                                 InstanceBits;
3414     unsigned FactoryBits = Methods.Factory.getBits();
3415     assert(FactoryBits < 4);
3416     unsigned FactoryHasMoreThanOneDeclBit =
3417         Methods.Factory.hasMoreThanOneDecl();
3418     unsigned FullFactoryBits = (NumFactoryMethods << 3) |
3419                                (FactoryHasMoreThanOneDeclBit << 2) |
3420                                FactoryBits;
3421     LE.write<uint16_t>(FullInstanceBits);
3422     LE.write<uint16_t>(FullFactoryBits);
3423     for (const ObjCMethodList *Method = &Methods.Instance; Method;
3424          Method = Method->getNext())
3425       if (Method->getMethod())
3426         LE.write<uint32_t>(Writer.getDeclID(Method->getMethod()));
3427     for (const ObjCMethodList *Method = &Methods.Factory; Method;
3428          Method = Method->getNext())
3429       if (Method->getMethod())
3430         LE.write<uint32_t>(Writer.getDeclID(Method->getMethod()));
3431 
3432     assert(Out.tell() - Start == DataLen && "Data length is wrong");
3433   }
3434 };
3435 
3436 } // namespace
3437 
3438 /// Write ObjC data: selectors and the method pool.
3439 ///
3440 /// The method pool contains both instance and factory methods, stored
3441 /// in an on-disk hash table indexed by the selector. The hash table also
3442 /// contains an empty entry for every other selector known to Sema.
3443 void ASTWriter::WriteSelectors(Sema &SemaRef) {
3444   using namespace llvm;
3445 
3446   // Do we have to do anything at all?
3447   if (SemaRef.MethodPool.empty() && SelectorIDs.empty())
3448     return;
3449   unsigned NumTableEntries = 0;
3450   // Create and write out the blob that contains selectors and the method pool.
3451   {
3452     llvm::OnDiskChainedHashTableGenerator<ASTMethodPoolTrait> Generator;
3453     ASTMethodPoolTrait Trait(*this);
3454 
3455     // Create the on-disk hash table representation. We walk through every
3456     // selector we've seen and look it up in the method pool.
3457     SelectorOffsets.resize(NextSelectorID - FirstSelectorID);
3458     for (auto &SelectorAndID : SelectorIDs) {
3459       Selector S = SelectorAndID.first;
3460       SelectorID ID = SelectorAndID.second;
3461       Sema::GlobalMethodPool::iterator F = SemaRef.MethodPool.find(S);
3462       ASTMethodPoolTrait::data_type Data = {
3463         ID,
3464         ObjCMethodList(),
3465         ObjCMethodList()
3466       };
3467       if (F != SemaRef.MethodPool.end()) {
3468         Data.Instance = F->second.first;
3469         Data.Factory = F->second.second;
3470       }
3471       // Only write this selector if it's not in an existing AST or something
3472       // changed.
3473       if (Chain && ID < FirstSelectorID) {
3474         // Selector already exists. Did it change?
3475         bool changed = false;
3476         for (ObjCMethodList *M = &Data.Instance;
3477              !changed && M && M->getMethod(); M = M->getNext()) {
3478           if (!M->getMethod()->isFromASTFile())
3479             changed = true;
3480         }
3481         for (ObjCMethodList *M = &Data.Factory; !changed && M && M->getMethod();
3482              M = M->getNext()) {
3483           if (!M->getMethod()->isFromASTFile())
3484             changed = true;
3485         }
3486         if (!changed)
3487           continue;
3488       } else if (Data.Instance.getMethod() || Data.Factory.getMethod()) {
3489         // A new method pool entry.
3490         ++NumTableEntries;
3491       }
3492       Generator.insert(S, Data, Trait);
3493     }
3494 
3495     // Create the on-disk hash table in a buffer.
3496     SmallString<4096> MethodPool;
3497     uint32_t BucketOffset;
3498     {
3499       using namespace llvm::support;
3500 
3501       ASTMethodPoolTrait Trait(*this);
3502       llvm::raw_svector_ostream Out(MethodPool);
3503       // Make sure that no bucket is at offset 0
3504       endian::write<uint32_t>(Out, 0, little);
3505       BucketOffset = Generator.Emit(Out, Trait);
3506     }
3507 
3508     // Create a blob abbreviation
3509     auto Abbrev = std::make_shared<BitCodeAbbrev>();
3510     Abbrev->Add(BitCodeAbbrevOp(METHOD_POOL));
3511     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
3512     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
3513     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3514     unsigned MethodPoolAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3515 
3516     // Write the method pool
3517     {
3518       RecordData::value_type Record[] = {METHOD_POOL, BucketOffset,
3519                                          NumTableEntries};
3520       Stream.EmitRecordWithBlob(MethodPoolAbbrev, Record, MethodPool);
3521     }
3522 
3523     // Create a blob abbreviation for the selector table offsets.
3524     Abbrev = std::make_shared<BitCodeAbbrev>();
3525     Abbrev->Add(BitCodeAbbrevOp(SELECTOR_OFFSETS));
3526     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // size
3527     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // first ID
3528     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3529     unsigned SelectorOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3530 
3531     // Write the selector offsets table.
3532     {
3533       RecordData::value_type Record[] = {
3534           SELECTOR_OFFSETS, SelectorOffsets.size(),
3535           FirstSelectorID - NUM_PREDEF_SELECTOR_IDS};
3536       Stream.EmitRecordWithBlob(SelectorOffsetAbbrev, Record,
3537                                 bytes(SelectorOffsets));
3538     }
3539   }
3540 }
3541 
3542 /// Write the selectors referenced in @selector expression into AST file.
3543 void ASTWriter::WriteReferencedSelectorsPool(Sema &SemaRef) {
3544   using namespace llvm;
3545 
3546   if (SemaRef.ReferencedSelectors.empty())
3547     return;
3548 
3549   RecordData Record;
3550   ASTRecordWriter Writer(*this, Record);
3551 
3552   // Note: this writes out all references even for a dependent AST. But it is
3553   // very tricky to fix, and given that @selector shouldn't really appear in
3554   // headers, probably not worth it. It's not a correctness issue.
3555   for (auto &SelectorAndLocation : SemaRef.ReferencedSelectors) {
3556     Selector Sel = SelectorAndLocation.first;
3557     SourceLocation Loc = SelectorAndLocation.second;
3558     Writer.AddSelectorRef(Sel);
3559     Writer.AddSourceLocation(Loc);
3560   }
3561   Writer.Emit(REFERENCED_SELECTOR_POOL);
3562 }
3563 
3564 //===----------------------------------------------------------------------===//
3565 // Identifier Table Serialization
3566 //===----------------------------------------------------------------------===//
3567 
3568 /// Determine the declaration that should be put into the name lookup table to
3569 /// represent the given declaration in this module. This is usually D itself,
3570 /// but if D was imported and merged into a local declaration, we want the most
3571 /// recent local declaration instead. The chosen declaration will be the most
3572 /// recent declaration in any module that imports this one.
3573 static NamedDecl *getDeclForLocalLookup(const LangOptions &LangOpts,
3574                                         NamedDecl *D) {
3575   if (!LangOpts.Modules || !D->isFromASTFile())
3576     return D;
3577 
3578   if (Decl *Redecl = D->getPreviousDecl()) {
3579     // For Redeclarable decls, a prior declaration might be local.
3580     for (; Redecl; Redecl = Redecl->getPreviousDecl()) {
3581       // If we find a local decl, we're done.
3582       if (!Redecl->isFromASTFile()) {
3583         // Exception: in very rare cases (for injected-class-names), not all
3584         // redeclarations are in the same semantic context. Skip ones in a
3585         // different context. They don't go in this lookup table at all.
3586         if (!Redecl->getDeclContext()->getRedeclContext()->Equals(
3587                 D->getDeclContext()->getRedeclContext()))
3588           continue;
3589         return cast<NamedDecl>(Redecl);
3590       }
3591 
3592       // If we find a decl from a (chained-)PCH stop since we won't find a
3593       // local one.
3594       if (Redecl->getOwningModuleID() == 0)
3595         break;
3596     }
3597   } else if (Decl *First = D->getCanonicalDecl()) {
3598     // For Mergeable decls, the first decl might be local.
3599     if (!First->isFromASTFile())
3600       return cast<NamedDecl>(First);
3601   }
3602 
3603   // All declarations are imported. Our most recent declaration will also be
3604   // the most recent one in anyone who imports us.
3605   return D;
3606 }
3607 
3608 namespace {
3609 
3610 class ASTIdentifierTableTrait {
3611   ASTWriter &Writer;
3612   Preprocessor &PP;
3613   IdentifierResolver &IdResolver;
3614   bool IsModule;
3615   bool NeedDecls;
3616   ASTWriter::RecordData *InterestingIdentifierOffsets;
3617 
3618   /// Determines whether this is an "interesting" identifier that needs a
3619   /// full IdentifierInfo structure written into the hash table. Notably, this
3620   /// doesn't check whether the name has macros defined; use PublicMacroIterator
3621   /// to check that.
3622   bool isInterestingIdentifier(const IdentifierInfo *II, uint64_t MacroOffset) {
3623     if (MacroOffset ||
3624         II->isPoisoned() ||
3625         (IsModule ? II->hasRevertedBuiltin() : II->getObjCOrBuiltinID()) ||
3626         II->hasRevertedTokenIDToIdentifier() ||
3627         (NeedDecls && II->getFETokenInfo()))
3628       return true;
3629 
3630     return false;
3631   }
3632 
3633 public:
3634   using key_type = IdentifierInfo *;
3635   using key_type_ref = key_type;
3636 
3637   using data_type = IdentID;
3638   using data_type_ref = data_type;
3639 
3640   using hash_value_type = unsigned;
3641   using offset_type = unsigned;
3642 
3643   ASTIdentifierTableTrait(ASTWriter &Writer, Preprocessor &PP,
3644                           IdentifierResolver &IdResolver, bool IsModule,
3645                           ASTWriter::RecordData *InterestingIdentifierOffsets)
3646       : Writer(Writer), PP(PP), IdResolver(IdResolver), IsModule(IsModule),
3647         NeedDecls(!IsModule || !Writer.getLangOpts().CPlusPlus),
3648         InterestingIdentifierOffsets(InterestingIdentifierOffsets) {}
3649 
3650   bool needDecls() const { return NeedDecls; }
3651 
3652   static hash_value_type ComputeHash(const IdentifierInfo* II) {
3653     return llvm::djbHash(II->getName());
3654   }
3655 
3656   bool isInterestingIdentifier(const IdentifierInfo *II) {
3657     auto MacroOffset = Writer.getMacroDirectivesOffset(II);
3658     return isInterestingIdentifier(II, MacroOffset);
3659   }
3660 
3661   bool isInterestingNonMacroIdentifier(const IdentifierInfo *II) {
3662     return isInterestingIdentifier(II, 0);
3663   }
3664 
3665   std::pair<unsigned, unsigned>
3666   EmitKeyDataLength(raw_ostream& Out, IdentifierInfo* II, IdentID ID) {
3667     unsigned KeyLen = II->getLength() + 1;
3668     unsigned DataLen = 4; // 4 bytes for the persistent ID << 1
3669     auto MacroOffset = Writer.getMacroDirectivesOffset(II);
3670     if (isInterestingIdentifier(II, MacroOffset)) {
3671       DataLen += 2; // 2 bytes for builtin ID
3672       DataLen += 2; // 2 bytes for flags
3673       if (MacroOffset)
3674         DataLen += 4; // MacroDirectives offset.
3675 
3676       if (NeedDecls) {
3677         for (IdentifierResolver::iterator D = IdResolver.begin(II),
3678                                        DEnd = IdResolver.end();
3679              D != DEnd; ++D)
3680           DataLen += 4;
3681       }
3682     }
3683 
3684     using namespace llvm::support;
3685 
3686     endian::Writer LE(Out, little);
3687 
3688     assert((uint16_t)DataLen == DataLen && (uint16_t)KeyLen == KeyLen);
3689     LE.write<uint16_t>(DataLen);
3690     // We emit the key length after the data length so that every
3691     // string is preceded by a 16-bit length. This matches the PTH
3692     // format for storing identifiers.
3693     LE.write<uint16_t>(KeyLen);
3694     return std::make_pair(KeyLen, DataLen);
3695   }
3696 
3697   void EmitKey(raw_ostream& Out, const IdentifierInfo* II,
3698                unsigned KeyLen) {
3699     // Record the location of the key data.  This is used when generating
3700     // the mapping from persistent IDs to strings.
3701     Writer.SetIdentifierOffset(II, Out.tell());
3702 
3703     // Emit the offset of the key/data length information to the interesting
3704     // identifiers table if necessary.
3705     if (InterestingIdentifierOffsets && isInterestingIdentifier(II))
3706       InterestingIdentifierOffsets->push_back(Out.tell() - 4);
3707 
3708     Out.write(II->getNameStart(), KeyLen);
3709   }
3710 
3711   void EmitData(raw_ostream& Out, IdentifierInfo* II,
3712                 IdentID ID, unsigned) {
3713     using namespace llvm::support;
3714 
3715     endian::Writer LE(Out, little);
3716 
3717     auto MacroOffset = Writer.getMacroDirectivesOffset(II);
3718     if (!isInterestingIdentifier(II, MacroOffset)) {
3719       LE.write<uint32_t>(ID << 1);
3720       return;
3721     }
3722 
3723     LE.write<uint32_t>((ID << 1) | 0x01);
3724     uint32_t Bits = (uint32_t)II->getObjCOrBuiltinID();
3725     assert((Bits & 0xffff) == Bits && "ObjCOrBuiltinID too big for ASTReader.");
3726     LE.write<uint16_t>(Bits);
3727     Bits = 0;
3728     bool HadMacroDefinition = MacroOffset != 0;
3729     Bits = (Bits << 1) | unsigned(HadMacroDefinition);
3730     Bits = (Bits << 1) | unsigned(II->isExtensionToken());
3731     Bits = (Bits << 1) | unsigned(II->isPoisoned());
3732     Bits = (Bits << 1) | unsigned(II->hasRevertedBuiltin());
3733     Bits = (Bits << 1) | unsigned(II->hasRevertedTokenIDToIdentifier());
3734     Bits = (Bits << 1) | unsigned(II->isCPlusPlusOperatorKeyword());
3735     LE.write<uint16_t>(Bits);
3736 
3737     if (HadMacroDefinition)
3738       LE.write<uint32_t>(MacroOffset);
3739 
3740     if (NeedDecls) {
3741       // Emit the declaration IDs in reverse order, because the
3742       // IdentifierResolver provides the declarations as they would be
3743       // visible (e.g., the function "stat" would come before the struct
3744       // "stat"), but the ASTReader adds declarations to the end of the list
3745       // (so we need to see the struct "stat" before the function "stat").
3746       // Only emit declarations that aren't from a chained PCH, though.
3747       SmallVector<NamedDecl *, 16> Decls(IdResolver.begin(II),
3748                                          IdResolver.end());
3749       for (SmallVectorImpl<NamedDecl *>::reverse_iterator D = Decls.rbegin(),
3750                                                           DEnd = Decls.rend();
3751            D != DEnd; ++D)
3752         LE.write<uint32_t>(
3753             Writer.getDeclID(getDeclForLocalLookup(PP.getLangOpts(), *D)));
3754     }
3755   }
3756 };
3757 
3758 } // namespace
3759 
3760 /// Write the identifier table into the AST file.
3761 ///
3762 /// The identifier table consists of a blob containing string data
3763 /// (the actual identifiers themselves) and a separate "offsets" index
3764 /// that maps identifier IDs to locations within the blob.
3765 void ASTWriter::WriteIdentifierTable(Preprocessor &PP,
3766                                      IdentifierResolver &IdResolver,
3767                                      bool IsModule) {
3768   using namespace llvm;
3769 
3770   RecordData InterestingIdents;
3771 
3772   // Create and write out the blob that contains the identifier
3773   // strings.
3774   {
3775     llvm::OnDiskChainedHashTableGenerator<ASTIdentifierTableTrait> Generator;
3776     ASTIdentifierTableTrait Trait(
3777         *this, PP, IdResolver, IsModule,
3778         (getLangOpts().CPlusPlus && IsModule) ? &InterestingIdents : nullptr);
3779 
3780     // Look for any identifiers that were named while processing the
3781     // headers, but are otherwise not needed. We add these to the hash
3782     // table to enable checking of the predefines buffer in the case
3783     // where the user adds new macro definitions when building the AST
3784     // file.
3785     SmallVector<const IdentifierInfo *, 128> IIs;
3786     for (const auto &ID : PP.getIdentifierTable())
3787       IIs.push_back(ID.second);
3788     // Sort the identifiers lexicographically before getting them references so
3789     // that their order is stable.
3790     llvm::sort(IIs, llvm::deref<std::less<>>());
3791     for (const IdentifierInfo *II : IIs)
3792       if (Trait.isInterestingNonMacroIdentifier(II))
3793         getIdentifierRef(II);
3794 
3795     // Create the on-disk hash table representation. We only store offsets
3796     // for identifiers that appear here for the first time.
3797     IdentifierOffsets.resize(NextIdentID - FirstIdentID);
3798     for (auto IdentIDPair : IdentifierIDs) {
3799       auto *II = const_cast<IdentifierInfo *>(IdentIDPair.first);
3800       IdentID ID = IdentIDPair.second;
3801       assert(II && "NULL identifier in identifier table");
3802       // Write out identifiers if either the ID is local or the identifier has
3803       // changed since it was loaded.
3804       if (ID >= FirstIdentID || !Chain || !II->isFromAST()
3805           || II->hasChangedSinceDeserialization() ||
3806           (Trait.needDecls() &&
3807            II->hasFETokenInfoChangedSinceDeserialization()))
3808         Generator.insert(II, ID, Trait);
3809     }
3810 
3811     // Create the on-disk hash table in a buffer.
3812     SmallString<4096> IdentifierTable;
3813     uint32_t BucketOffset;
3814     {
3815       using namespace llvm::support;
3816 
3817       llvm::raw_svector_ostream Out(IdentifierTable);
3818       // Make sure that no bucket is at offset 0
3819       endian::write<uint32_t>(Out, 0, little);
3820       BucketOffset = Generator.Emit(Out, Trait);
3821     }
3822 
3823     // Create a blob abbreviation
3824     auto Abbrev = std::make_shared<BitCodeAbbrev>();
3825     Abbrev->Add(BitCodeAbbrevOp(IDENTIFIER_TABLE));
3826     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
3827     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3828     unsigned IDTableAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3829 
3830     // Write the identifier table
3831     RecordData::value_type Record[] = {IDENTIFIER_TABLE, BucketOffset};
3832     Stream.EmitRecordWithBlob(IDTableAbbrev, Record, IdentifierTable);
3833   }
3834 
3835   // Write the offsets table for identifier IDs.
3836   auto Abbrev = std::make_shared<BitCodeAbbrev>();
3837   Abbrev->Add(BitCodeAbbrevOp(IDENTIFIER_OFFSET));
3838   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // # of identifiers
3839   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); // first ID
3840   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
3841   unsigned IdentifierOffsetAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
3842 
3843 #ifndef NDEBUG
3844   for (unsigned I = 0, N = IdentifierOffsets.size(); I != N; ++I)
3845     assert(IdentifierOffsets[I] && "Missing identifier offset?");
3846 #endif
3847 
3848   RecordData::value_type Record[] = {IDENTIFIER_OFFSET,
3849                                      IdentifierOffsets.size(),
3850                                      FirstIdentID - NUM_PREDEF_IDENT_IDS};
3851   Stream.EmitRecordWithBlob(IdentifierOffsetAbbrev, Record,
3852                             bytes(IdentifierOffsets));
3853 
3854   // In C++, write the list of interesting identifiers (those that are
3855   // defined as macros, poisoned, or similar unusual things).
3856   if (!InterestingIdents.empty())
3857     Stream.EmitRecord(INTERESTING_IDENTIFIERS, InterestingIdents);
3858 }
3859 
3860 //===----------------------------------------------------------------------===//
3861 // DeclContext's Name Lookup Table Serialization
3862 //===----------------------------------------------------------------------===//
3863 
3864 namespace {
3865 
3866 // Trait used for the on-disk hash table used in the method pool.
3867 class ASTDeclContextNameLookupTrait {
3868   ASTWriter &Writer;
3869   llvm::SmallVector<DeclID, 64> DeclIDs;
3870 
3871 public:
3872   using key_type = DeclarationNameKey;
3873   using key_type_ref = key_type;
3874 
3875   /// A start and end index into DeclIDs, representing a sequence of decls.
3876   using data_type = std::pair<unsigned, unsigned>;
3877   using data_type_ref = const data_type &;
3878 
3879   using hash_value_type = unsigned;
3880   using offset_type = unsigned;
3881 
3882   explicit ASTDeclContextNameLookupTrait(ASTWriter &Writer) : Writer(Writer) {}
3883 
3884   template<typename Coll>
3885   data_type getData(const Coll &Decls) {
3886     unsigned Start = DeclIDs.size();
3887     for (NamedDecl *D : Decls) {
3888       DeclIDs.push_back(
3889           Writer.GetDeclRef(getDeclForLocalLookup(Writer.getLangOpts(), D)));
3890     }
3891     return std::make_pair(Start, DeclIDs.size());
3892   }
3893 
3894   data_type ImportData(const reader::ASTDeclContextNameLookupTrait::data_type &FromReader) {
3895     unsigned Start = DeclIDs.size();
3896     for (auto ID : FromReader)
3897       DeclIDs.push_back(ID);
3898     return std::make_pair(Start, DeclIDs.size());
3899   }
3900 
3901   static bool EqualKey(key_type_ref a, key_type_ref b) {
3902     return a == b;
3903   }
3904 
3905   hash_value_type ComputeHash(DeclarationNameKey Name) {
3906     return Name.getHash();
3907   }
3908 
3909   void EmitFileRef(raw_ostream &Out, ModuleFile *F) const {
3910     assert(Writer.hasChain() &&
3911            "have reference to loaded module file but no chain?");
3912 
3913     using namespace llvm::support;
3914 
3915     endian::write<uint32_t>(Out, Writer.getChain()->getModuleFileID(F), little);
3916   }
3917 
3918   std::pair<unsigned, unsigned> EmitKeyDataLength(raw_ostream &Out,
3919                                                   DeclarationNameKey Name,
3920                                                   data_type_ref Lookup) {
3921     using namespace llvm::support;
3922 
3923     endian::Writer LE(Out, little);
3924     unsigned KeyLen = 1;
3925     switch (Name.getKind()) {
3926     case DeclarationName::Identifier:
3927     case DeclarationName::ObjCZeroArgSelector:
3928     case DeclarationName::ObjCOneArgSelector:
3929     case DeclarationName::ObjCMultiArgSelector:
3930     case DeclarationName::CXXLiteralOperatorName:
3931     case DeclarationName::CXXDeductionGuideName:
3932       KeyLen += 4;
3933       break;
3934     case DeclarationName::CXXOperatorName:
3935       KeyLen += 1;
3936       break;
3937     case DeclarationName::CXXConstructorName:
3938     case DeclarationName::CXXDestructorName:
3939     case DeclarationName::CXXConversionFunctionName:
3940     case DeclarationName::CXXUsingDirective:
3941       break;
3942     }
3943     LE.write<uint16_t>(KeyLen);
3944 
3945     // 4 bytes for each DeclID.
3946     unsigned DataLen = 4 * (Lookup.second - Lookup.first);
3947     assert(uint16_t(DataLen) == DataLen &&
3948            "too many decls for serialized lookup result");
3949     LE.write<uint16_t>(DataLen);
3950 
3951     return std::make_pair(KeyLen, DataLen);
3952   }
3953 
3954   void EmitKey(raw_ostream &Out, DeclarationNameKey Name, unsigned) {
3955     using namespace llvm::support;
3956 
3957     endian::Writer LE(Out, little);
3958     LE.write<uint8_t>(Name.getKind());
3959     switch (Name.getKind()) {
3960     case DeclarationName::Identifier:
3961     case DeclarationName::CXXLiteralOperatorName:
3962     case DeclarationName::CXXDeductionGuideName:
3963       LE.write<uint32_t>(Writer.getIdentifierRef(Name.getIdentifier()));
3964       return;
3965     case DeclarationName::ObjCZeroArgSelector:
3966     case DeclarationName::ObjCOneArgSelector:
3967     case DeclarationName::ObjCMultiArgSelector:
3968       LE.write<uint32_t>(Writer.getSelectorRef(Name.getSelector()));
3969       return;
3970     case DeclarationName::CXXOperatorName:
3971       assert(Name.getOperatorKind() < NUM_OVERLOADED_OPERATORS &&
3972              "Invalid operator?");
3973       LE.write<uint8_t>(Name.getOperatorKind());
3974       return;
3975     case DeclarationName::CXXConstructorName:
3976     case DeclarationName::CXXDestructorName:
3977     case DeclarationName::CXXConversionFunctionName:
3978     case DeclarationName::CXXUsingDirective:
3979       return;
3980     }
3981 
3982     llvm_unreachable("Invalid name kind?");
3983   }
3984 
3985   void EmitData(raw_ostream &Out, key_type_ref, data_type Lookup,
3986                 unsigned DataLen) {
3987     using namespace llvm::support;
3988 
3989     endian::Writer LE(Out, little);
3990     uint64_t Start = Out.tell(); (void)Start;
3991     for (unsigned I = Lookup.first, N = Lookup.second; I != N; ++I)
3992       LE.write<uint32_t>(DeclIDs[I]);
3993     assert(Out.tell() - Start == DataLen && "Data length is wrong");
3994   }
3995 };
3996 
3997 } // namespace
3998 
3999 bool ASTWriter::isLookupResultExternal(StoredDeclsList &Result,
4000                                        DeclContext *DC) {
4001   return Result.hasExternalDecls() &&
4002          DC->hasNeedToReconcileExternalVisibleStorage();
4003 }
4004 
4005 bool ASTWriter::isLookupResultEntirelyExternal(StoredDeclsList &Result,
4006                                                DeclContext *DC) {
4007   for (auto *D : Result.getLookupResult())
4008     if (!getDeclForLocalLookup(getLangOpts(), D)->isFromASTFile())
4009       return false;
4010 
4011   return true;
4012 }
4013 
4014 void
4015 ASTWriter::GenerateNameLookupTable(const DeclContext *ConstDC,
4016                                    llvm::SmallVectorImpl<char> &LookupTable) {
4017   assert(!ConstDC->hasLazyLocalLexicalLookups() &&
4018          !ConstDC->hasLazyExternalLexicalLookups() &&
4019          "must call buildLookups first");
4020 
4021   // FIXME: We need to build the lookups table, which is logically const.
4022   auto *DC = const_cast<DeclContext*>(ConstDC);
4023   assert(DC == DC->getPrimaryContext() && "only primary DC has lookup table");
4024 
4025   // Create the on-disk hash table representation.
4026   MultiOnDiskHashTableGenerator<reader::ASTDeclContextNameLookupTrait,
4027                                 ASTDeclContextNameLookupTrait> Generator;
4028   ASTDeclContextNameLookupTrait Trait(*this);
4029 
4030   // The first step is to collect the declaration names which we need to
4031   // serialize into the name lookup table, and to collect them in a stable
4032   // order.
4033   SmallVector<DeclarationName, 16> Names;
4034 
4035   // We also build up small sets of the constructor and conversion function
4036   // names which are visible.
4037   llvm::SmallSet<DeclarationName, 8> ConstructorNameSet, ConversionNameSet;
4038 
4039   for (auto &Lookup : *DC->buildLookup()) {
4040     auto &Name = Lookup.first;
4041     auto &Result = Lookup.second;
4042 
4043     // If there are no local declarations in our lookup result, we
4044     // don't need to write an entry for the name at all. If we can't
4045     // write out a lookup set without performing more deserialization,
4046     // just skip this entry.
4047     if (isLookupResultExternal(Result, DC) &&
4048         isLookupResultEntirelyExternal(Result, DC))
4049       continue;
4050 
4051     // We also skip empty results. If any of the results could be external and
4052     // the currently available results are empty, then all of the results are
4053     // external and we skip it above. So the only way we get here with an empty
4054     // results is when no results could have been external *and* we have
4055     // external results.
4056     //
4057     // FIXME: While we might want to start emitting on-disk entries for negative
4058     // lookups into a decl context as an optimization, today we *have* to skip
4059     // them because there are names with empty lookup results in decl contexts
4060     // which we can't emit in any stable ordering: we lookup constructors and
4061     // conversion functions in the enclosing namespace scope creating empty
4062     // results for them. This in almost certainly a bug in Clang's name lookup,
4063     // but that is likely to be hard or impossible to fix and so we tolerate it
4064     // here by omitting lookups with empty results.
4065     if (Lookup.second.getLookupResult().empty())
4066       continue;
4067 
4068     switch (Lookup.first.getNameKind()) {
4069     default:
4070       Names.push_back(Lookup.first);
4071       break;
4072 
4073     case DeclarationName::CXXConstructorName:
4074       assert(isa<CXXRecordDecl>(DC) &&
4075              "Cannot have a constructor name outside of a class!");
4076       ConstructorNameSet.insert(Name);
4077       break;
4078 
4079     case DeclarationName::CXXConversionFunctionName:
4080       assert(isa<CXXRecordDecl>(DC) &&
4081              "Cannot have a conversion function name outside of a class!");
4082       ConversionNameSet.insert(Name);
4083       break;
4084     }
4085   }
4086 
4087   // Sort the names into a stable order.
4088   llvm::sort(Names);
4089 
4090   if (auto *D = dyn_cast<CXXRecordDecl>(DC)) {
4091     // We need to establish an ordering of constructor and conversion function
4092     // names, and they don't have an intrinsic ordering.
4093 
4094     // First we try the easy case by forming the current context's constructor
4095     // name and adding that name first. This is a very useful optimization to
4096     // avoid walking the lexical declarations in many cases, and it also
4097     // handles the only case where a constructor name can come from some other
4098     // lexical context -- when that name is an implicit constructor merged from
4099     // another declaration in the redecl chain. Any non-implicit constructor or
4100     // conversion function which doesn't occur in all the lexical contexts
4101     // would be an ODR violation.
4102     auto ImplicitCtorName = Context->DeclarationNames.getCXXConstructorName(
4103         Context->getCanonicalType(Context->getRecordType(D)));
4104     if (ConstructorNameSet.erase(ImplicitCtorName))
4105       Names.push_back(ImplicitCtorName);
4106 
4107     // If we still have constructors or conversion functions, we walk all the
4108     // names in the decl and add the constructors and conversion functions
4109     // which are visible in the order they lexically occur within the context.
4110     if (!ConstructorNameSet.empty() || !ConversionNameSet.empty())
4111       for (Decl *ChildD : cast<CXXRecordDecl>(DC)->decls())
4112         if (auto *ChildND = dyn_cast<NamedDecl>(ChildD)) {
4113           auto Name = ChildND->getDeclName();
4114           switch (Name.getNameKind()) {
4115           default:
4116             continue;
4117 
4118           case DeclarationName::CXXConstructorName:
4119             if (ConstructorNameSet.erase(Name))
4120               Names.push_back(Name);
4121             break;
4122 
4123           case DeclarationName::CXXConversionFunctionName:
4124             if (ConversionNameSet.erase(Name))
4125               Names.push_back(Name);
4126             break;
4127           }
4128 
4129           if (ConstructorNameSet.empty() && ConversionNameSet.empty())
4130             break;
4131         }
4132 
4133     assert(ConstructorNameSet.empty() && "Failed to find all of the visible "
4134                                          "constructors by walking all the "
4135                                          "lexical members of the context.");
4136     assert(ConversionNameSet.empty() && "Failed to find all of the visible "
4137                                         "conversion functions by walking all "
4138                                         "the lexical members of the context.");
4139   }
4140 
4141   // Next we need to do a lookup with each name into this decl context to fully
4142   // populate any results from external sources. We don't actually use the
4143   // results of these lookups because we only want to use the results after all
4144   // results have been loaded and the pointers into them will be stable.
4145   for (auto &Name : Names)
4146     DC->lookup(Name);
4147 
4148   // Now we need to insert the results for each name into the hash table. For
4149   // constructor names and conversion function names, we actually need to merge
4150   // all of the results for them into one list of results each and insert
4151   // those.
4152   SmallVector<NamedDecl *, 8> ConstructorDecls;
4153   SmallVector<NamedDecl *, 8> ConversionDecls;
4154 
4155   // Now loop over the names, either inserting them or appending for the two
4156   // special cases.
4157   for (auto &Name : Names) {
4158     DeclContext::lookup_result Result = DC->noload_lookup(Name);
4159 
4160     switch (Name.getNameKind()) {
4161     default:
4162       Generator.insert(Name, Trait.getData(Result), Trait);
4163       break;
4164 
4165     case DeclarationName::CXXConstructorName:
4166       ConstructorDecls.append(Result.begin(), Result.end());
4167       break;
4168 
4169     case DeclarationName::CXXConversionFunctionName:
4170       ConversionDecls.append(Result.begin(), Result.end());
4171       break;
4172     }
4173   }
4174 
4175   // Handle our two special cases if we ended up having any. We arbitrarily use
4176   // the first declaration's name here because the name itself isn't part of
4177   // the key, only the kind of name is used.
4178   if (!ConstructorDecls.empty())
4179     Generator.insert(ConstructorDecls.front()->getDeclName(),
4180                      Trait.getData(ConstructorDecls), Trait);
4181   if (!ConversionDecls.empty())
4182     Generator.insert(ConversionDecls.front()->getDeclName(),
4183                      Trait.getData(ConversionDecls), Trait);
4184 
4185   // Create the on-disk hash table. Also emit the existing imported and
4186   // merged table if there is one.
4187   auto *Lookups = Chain ? Chain->getLoadedLookupTables(DC) : nullptr;
4188   Generator.emit(LookupTable, Trait, Lookups ? &Lookups->Table : nullptr);
4189 }
4190 
4191 /// Write the block containing all of the declaration IDs
4192 /// visible from the given DeclContext.
4193 ///
4194 /// \returns the offset of the DECL_CONTEXT_VISIBLE block within the
4195 /// bitstream, or 0 if no block was written.
4196 uint64_t ASTWriter::WriteDeclContextVisibleBlock(ASTContext &Context,
4197                                                  DeclContext *DC) {
4198   // If we imported a key declaration of this namespace, write the visible
4199   // lookup results as an update record for it rather than including them
4200   // on this declaration. We will only look at key declarations on reload.
4201   if (isa<NamespaceDecl>(DC) && Chain &&
4202       Chain->getKeyDeclaration(cast<Decl>(DC))->isFromASTFile()) {
4203     // Only do this once, for the first local declaration of the namespace.
4204     for (auto *Prev = cast<NamespaceDecl>(DC)->getPreviousDecl(); Prev;
4205          Prev = Prev->getPreviousDecl())
4206       if (!Prev->isFromASTFile())
4207         return 0;
4208 
4209     // Note that we need to emit an update record for the primary context.
4210     UpdatedDeclContexts.insert(DC->getPrimaryContext());
4211 
4212     // Make sure all visible decls are written. They will be recorded later. We
4213     // do this using a side data structure so we can sort the names into
4214     // a deterministic order.
4215     StoredDeclsMap *Map = DC->getPrimaryContext()->buildLookup();
4216     SmallVector<std::pair<DeclarationName, DeclContext::lookup_result>, 16>
4217         LookupResults;
4218     if (Map) {
4219       LookupResults.reserve(Map->size());
4220       for (auto &Entry : *Map)
4221         LookupResults.push_back(
4222             std::make_pair(Entry.first, Entry.second.getLookupResult()));
4223     }
4224 
4225     llvm::sort(LookupResults, llvm::less_first());
4226     for (auto &NameAndResult : LookupResults) {
4227       DeclarationName Name = NameAndResult.first;
4228       DeclContext::lookup_result Result = NameAndResult.second;
4229       if (Name.getNameKind() == DeclarationName::CXXConstructorName ||
4230           Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
4231         // We have to work around a name lookup bug here where negative lookup
4232         // results for these names get cached in namespace lookup tables (these
4233         // names should never be looked up in a namespace).
4234         assert(Result.empty() && "Cannot have a constructor or conversion "
4235                                  "function name in a namespace!");
4236         continue;
4237       }
4238 
4239       for (NamedDecl *ND : Result)
4240         if (!ND->isFromASTFile())
4241           GetDeclRef(ND);
4242     }
4243 
4244     return 0;
4245   }
4246 
4247   if (DC->getPrimaryContext() != DC)
4248     return 0;
4249 
4250   // Skip contexts which don't support name lookup.
4251   if (!DC->isLookupContext())
4252     return 0;
4253 
4254   // If not in C++, we perform name lookup for the translation unit via the
4255   // IdentifierInfo chains, don't bother to build a visible-declarations table.
4256   if (DC->isTranslationUnit() && !Context.getLangOpts().CPlusPlus)
4257     return 0;
4258 
4259   // Serialize the contents of the mapping used for lookup. Note that,
4260   // although we have two very different code paths, the serialized
4261   // representation is the same for both cases: a declaration name,
4262   // followed by a size, followed by references to the visible
4263   // declarations that have that name.
4264   uint64_t Offset = Stream.GetCurrentBitNo();
4265   StoredDeclsMap *Map = DC->buildLookup();
4266   if (!Map || Map->empty())
4267     return 0;
4268 
4269   // Create the on-disk hash table in a buffer.
4270   SmallString<4096> LookupTable;
4271   GenerateNameLookupTable(DC, LookupTable);
4272 
4273   // Write the lookup table
4274   RecordData::value_type Record[] = {DECL_CONTEXT_VISIBLE};
4275   Stream.EmitRecordWithBlob(DeclContextVisibleLookupAbbrev, Record,
4276                             LookupTable);
4277   ++NumVisibleDeclContexts;
4278   return Offset;
4279 }
4280 
4281 /// Write an UPDATE_VISIBLE block for the given context.
4282 ///
4283 /// UPDATE_VISIBLE blocks contain the declarations that are added to an existing
4284 /// DeclContext in a dependent AST file. As such, they only exist for the TU
4285 /// (in C++), for namespaces, and for classes with forward-declared unscoped
4286 /// enumeration members (in C++11).
4287 void ASTWriter::WriteDeclContextVisibleUpdate(const DeclContext *DC) {
4288   StoredDeclsMap *Map = DC->getLookupPtr();
4289   if (!Map || Map->empty())
4290     return;
4291 
4292   // Create the on-disk hash table in a buffer.
4293   SmallString<4096> LookupTable;
4294   GenerateNameLookupTable(DC, LookupTable);
4295 
4296   // If we're updating a namespace, select a key declaration as the key for the
4297   // update record; those are the only ones that will be checked on reload.
4298   if (isa<NamespaceDecl>(DC))
4299     DC = cast<DeclContext>(Chain->getKeyDeclaration(cast<Decl>(DC)));
4300 
4301   // Write the lookup table
4302   RecordData::value_type Record[] = {UPDATE_VISIBLE, getDeclID(cast<Decl>(DC))};
4303   Stream.EmitRecordWithBlob(UpdateVisibleAbbrev, Record, LookupTable);
4304 }
4305 
4306 /// Write an FP_PRAGMA_OPTIONS block for the given FPOptions.
4307 void ASTWriter::WriteFPPragmaOptions(const FPOptions &Opts) {
4308   RecordData::value_type Record[] = {Opts.getInt()};
4309   Stream.EmitRecord(FP_PRAGMA_OPTIONS, Record);
4310 }
4311 
4312 /// Write an OPENCL_EXTENSIONS block for the given OpenCLOptions.
4313 void ASTWriter::WriteOpenCLExtensions(Sema &SemaRef) {
4314   if (!SemaRef.Context.getLangOpts().OpenCL)
4315     return;
4316 
4317   const OpenCLOptions &Opts = SemaRef.getOpenCLOptions();
4318   RecordData Record;
4319   for (const auto &I:Opts.OptMap) {
4320     AddString(I.getKey(), Record);
4321     auto V = I.getValue();
4322     Record.push_back(V.Supported ? 1 : 0);
4323     Record.push_back(V.Enabled ? 1 : 0);
4324     Record.push_back(V.Avail);
4325     Record.push_back(V.Core);
4326   }
4327   Stream.EmitRecord(OPENCL_EXTENSIONS, Record);
4328 }
4329 
4330 void ASTWriter::WriteOpenCLExtensionTypes(Sema &SemaRef) {
4331   if (!SemaRef.Context.getLangOpts().OpenCL)
4332     return;
4333 
4334   // Sort the elements of the map OpenCLTypeExtMap by TypeIDs,
4335   // without copying them.
4336   const llvm::DenseMap<const Type *, std::set<std::string>> &OpenCLTypeExtMap =
4337       SemaRef.OpenCLTypeExtMap;
4338   using ElementTy = std::pair<TypeID, const std::set<std::string> *>;
4339   llvm::SmallVector<ElementTy, 8> StableOpenCLTypeExtMap;
4340   StableOpenCLTypeExtMap.reserve(OpenCLTypeExtMap.size());
4341 
4342   for (const auto &I : OpenCLTypeExtMap)
4343     StableOpenCLTypeExtMap.emplace_back(
4344         getTypeID(I.first->getCanonicalTypeInternal()), &I.second);
4345 
4346   auto CompareByTypeID = [](const ElementTy &E1, const ElementTy &E2) -> bool {
4347     return E1.first < E2.first;
4348   };
4349   llvm::sort(StableOpenCLTypeExtMap, CompareByTypeID);
4350 
4351   RecordData Record;
4352   for (const ElementTy &E : StableOpenCLTypeExtMap) {
4353     Record.push_back(E.first); // TypeID
4354     const std::set<std::string> *ExtSet = E.second;
4355     Record.push_back(static_cast<unsigned>(ExtSet->size()));
4356     for (const std::string &Ext : *ExtSet)
4357       AddString(Ext, Record);
4358   }
4359 
4360   Stream.EmitRecord(OPENCL_EXTENSION_TYPES, Record);
4361 }
4362 
4363 void ASTWriter::WriteOpenCLExtensionDecls(Sema &SemaRef) {
4364   if (!SemaRef.Context.getLangOpts().OpenCL)
4365     return;
4366 
4367   // Sort the elements of the map OpenCLDeclExtMap by DeclIDs,
4368   // without copying them.
4369   const llvm::DenseMap<const Decl *, std::set<std::string>> &OpenCLDeclExtMap =
4370       SemaRef.OpenCLDeclExtMap;
4371   using ElementTy = std::pair<DeclID, const std::set<std::string> *>;
4372   llvm::SmallVector<ElementTy, 8> StableOpenCLDeclExtMap;
4373   StableOpenCLDeclExtMap.reserve(OpenCLDeclExtMap.size());
4374 
4375   for (const auto &I : OpenCLDeclExtMap)
4376     StableOpenCLDeclExtMap.emplace_back(getDeclID(I.first), &I.second);
4377 
4378   auto CompareByDeclID = [](const ElementTy &E1, const ElementTy &E2) -> bool {
4379     return E1.first < E2.first;
4380   };
4381   llvm::sort(StableOpenCLDeclExtMap, CompareByDeclID);
4382 
4383   RecordData Record;
4384   for (const ElementTy &E : StableOpenCLDeclExtMap) {
4385     Record.push_back(E.first); // DeclID
4386     const std::set<std::string> *ExtSet = E.second;
4387     Record.push_back(static_cast<unsigned>(ExtSet->size()));
4388     for (const std::string &Ext : *ExtSet)
4389       AddString(Ext, Record);
4390   }
4391 
4392   Stream.EmitRecord(OPENCL_EXTENSION_DECLS, Record);
4393 }
4394 
4395 void ASTWriter::WriteCUDAPragmas(Sema &SemaRef) {
4396   if (SemaRef.ForceCUDAHostDeviceDepth > 0) {
4397     RecordData::value_type Record[] = {SemaRef.ForceCUDAHostDeviceDepth};
4398     Stream.EmitRecord(CUDA_PRAGMA_FORCE_HOST_DEVICE_DEPTH, Record);
4399   }
4400 }
4401 
4402 void ASTWriter::WriteObjCCategories() {
4403   SmallVector<ObjCCategoriesInfo, 2> CategoriesMap;
4404   RecordData Categories;
4405 
4406   for (unsigned I = 0, N = ObjCClassesWithCategories.size(); I != N; ++I) {
4407     unsigned Size = 0;
4408     unsigned StartIndex = Categories.size();
4409 
4410     ObjCInterfaceDecl *Class = ObjCClassesWithCategories[I];
4411 
4412     // Allocate space for the size.
4413     Categories.push_back(0);
4414 
4415     // Add the categories.
4416     for (ObjCInterfaceDecl::known_categories_iterator
4417            Cat = Class->known_categories_begin(),
4418            CatEnd = Class->known_categories_end();
4419          Cat != CatEnd; ++Cat, ++Size) {
4420       assert(getDeclID(*Cat) != 0 && "Bogus category");
4421       AddDeclRef(*Cat, Categories);
4422     }
4423 
4424     // Update the size.
4425     Categories[StartIndex] = Size;
4426 
4427     // Record this interface -> category map.
4428     ObjCCategoriesInfo CatInfo = { getDeclID(Class), StartIndex };
4429     CategoriesMap.push_back(CatInfo);
4430   }
4431 
4432   // Sort the categories map by the definition ID, since the reader will be
4433   // performing binary searches on this information.
4434   llvm::array_pod_sort(CategoriesMap.begin(), CategoriesMap.end());
4435 
4436   // Emit the categories map.
4437   using namespace llvm;
4438 
4439   auto Abbrev = std::make_shared<BitCodeAbbrev>();
4440   Abbrev->Add(BitCodeAbbrevOp(OBJC_CATEGORIES_MAP));
4441   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // # of entries
4442   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
4443   unsigned AbbrevID = Stream.EmitAbbrev(std::move(Abbrev));
4444 
4445   RecordData::value_type Record[] = {OBJC_CATEGORIES_MAP, CategoriesMap.size()};
4446   Stream.EmitRecordWithBlob(AbbrevID, Record,
4447                             reinterpret_cast<char *>(CategoriesMap.data()),
4448                             CategoriesMap.size() * sizeof(ObjCCategoriesInfo));
4449 
4450   // Emit the category lists.
4451   Stream.EmitRecord(OBJC_CATEGORIES, Categories);
4452 }
4453 
4454 void ASTWriter::WriteLateParsedTemplates(Sema &SemaRef) {
4455   Sema::LateParsedTemplateMapT &LPTMap = SemaRef.LateParsedTemplateMap;
4456 
4457   if (LPTMap.empty())
4458     return;
4459 
4460   RecordData Record;
4461   for (auto &LPTMapEntry : LPTMap) {
4462     const FunctionDecl *FD = LPTMapEntry.first;
4463     LateParsedTemplate &LPT = *LPTMapEntry.second;
4464     AddDeclRef(FD, Record);
4465     AddDeclRef(LPT.D, Record);
4466     Record.push_back(LPT.Toks.size());
4467 
4468     for (const auto &Tok : LPT.Toks) {
4469       AddToken(Tok, Record);
4470     }
4471   }
4472   Stream.EmitRecord(LATE_PARSED_TEMPLATE, Record);
4473 }
4474 
4475 /// Write the state of 'pragma clang optimize' at the end of the module.
4476 void ASTWriter::WriteOptimizePragmaOptions(Sema &SemaRef) {
4477   RecordData Record;
4478   SourceLocation PragmaLoc = SemaRef.getOptimizeOffPragmaLocation();
4479   AddSourceLocation(PragmaLoc, Record);
4480   Stream.EmitRecord(OPTIMIZE_PRAGMA_OPTIONS, Record);
4481 }
4482 
4483 /// Write the state of 'pragma ms_struct' at the end of the module.
4484 void ASTWriter::WriteMSStructPragmaOptions(Sema &SemaRef) {
4485   RecordData Record;
4486   Record.push_back(SemaRef.MSStructPragmaOn ? PMSST_ON : PMSST_OFF);
4487   Stream.EmitRecord(MSSTRUCT_PRAGMA_OPTIONS, Record);
4488 }
4489 
4490 /// Write the state of 'pragma pointers_to_members' at the end of the
4491 //module.
4492 void ASTWriter::WriteMSPointersToMembersPragmaOptions(Sema &SemaRef) {
4493   RecordData Record;
4494   Record.push_back(SemaRef.MSPointerToMemberRepresentationMethod);
4495   AddSourceLocation(SemaRef.ImplicitMSInheritanceAttrLoc, Record);
4496   Stream.EmitRecord(POINTERS_TO_MEMBERS_PRAGMA_OPTIONS, Record);
4497 }
4498 
4499 /// Write the state of 'pragma pack' at the end of the module.
4500 void ASTWriter::WritePackPragmaOptions(Sema &SemaRef) {
4501   // Don't serialize pragma pack state for modules, since it should only take
4502   // effect on a per-submodule basis.
4503   if (WritingModule)
4504     return;
4505 
4506   RecordData Record;
4507   Record.push_back(SemaRef.PackStack.CurrentValue);
4508   AddSourceLocation(SemaRef.PackStack.CurrentPragmaLocation, Record);
4509   Record.push_back(SemaRef.PackStack.Stack.size());
4510   for (const auto &StackEntry : SemaRef.PackStack.Stack) {
4511     Record.push_back(StackEntry.Value);
4512     AddSourceLocation(StackEntry.PragmaLocation, Record);
4513     AddSourceLocation(StackEntry.PragmaPushLocation, Record);
4514     AddString(StackEntry.StackSlotLabel, Record);
4515   }
4516   Stream.EmitRecord(PACK_PRAGMA_OPTIONS, Record);
4517 }
4518 
4519 void ASTWriter::WriteModuleFileExtension(Sema &SemaRef,
4520                                          ModuleFileExtensionWriter &Writer) {
4521   // Enter the extension block.
4522   Stream.EnterSubblock(EXTENSION_BLOCK_ID, 4);
4523 
4524   // Emit the metadata record abbreviation.
4525   auto Abv = std::make_shared<llvm::BitCodeAbbrev>();
4526   Abv->Add(llvm::BitCodeAbbrevOp(EXTENSION_METADATA));
4527   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4528   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4529   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4530   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4531   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Blob));
4532   unsigned Abbrev = Stream.EmitAbbrev(std::move(Abv));
4533 
4534   // Emit the metadata record.
4535   RecordData Record;
4536   auto Metadata = Writer.getExtension()->getExtensionMetadata();
4537   Record.push_back(EXTENSION_METADATA);
4538   Record.push_back(Metadata.MajorVersion);
4539   Record.push_back(Metadata.MinorVersion);
4540   Record.push_back(Metadata.BlockName.size());
4541   Record.push_back(Metadata.UserInfo.size());
4542   SmallString<64> Buffer;
4543   Buffer += Metadata.BlockName;
4544   Buffer += Metadata.UserInfo;
4545   Stream.EmitRecordWithBlob(Abbrev, Record, Buffer);
4546 
4547   // Emit the contents of the extension block.
4548   Writer.writeExtensionContents(SemaRef, Stream);
4549 
4550   // Exit the extension block.
4551   Stream.ExitBlock();
4552 }
4553 
4554 //===----------------------------------------------------------------------===//
4555 // General Serialization Routines
4556 //===----------------------------------------------------------------------===//
4557 
4558 void ASTRecordWriter::AddAttr(const Attr *A) {
4559   auto &Record = *this;
4560   if (!A)
4561     return Record.push_back(0);
4562   Record.push_back(A->getKind() + 1); // FIXME: stable encoding, target attrs
4563 
4564   Record.AddIdentifierRef(A->getAttrName());
4565   Record.AddIdentifierRef(A->getScopeName());
4566   Record.AddSourceRange(A->getRange());
4567   Record.AddSourceLocation(A->getScopeLoc());
4568   Record.push_back(A->getParsedKind());
4569   Record.push_back(A->getSyntax());
4570   Record.push_back(A->getAttributeSpellingListIndexRaw());
4571 
4572 #include "clang/Serialization/AttrPCHWrite.inc"
4573 }
4574 
4575 /// Emit the list of attributes to the specified record.
4576 void ASTRecordWriter::AddAttributes(ArrayRef<const Attr *> Attrs) {
4577   push_back(Attrs.size());
4578   for (const auto *A : Attrs)
4579     AddAttr(A);
4580 }
4581 
4582 void ASTWriter::AddToken(const Token &Tok, RecordDataImpl &Record) {
4583   AddSourceLocation(Tok.getLocation(), Record);
4584   Record.push_back(Tok.getLength());
4585 
4586   // FIXME: When reading literal tokens, reconstruct the literal pointer
4587   // if it is needed.
4588   AddIdentifierRef(Tok.getIdentifierInfo(), Record);
4589   // FIXME: Should translate token kind to a stable encoding.
4590   Record.push_back(Tok.getKind());
4591   // FIXME: Should translate token flags to a stable encoding.
4592   Record.push_back(Tok.getFlags());
4593 }
4594 
4595 void ASTWriter::AddString(StringRef Str, RecordDataImpl &Record) {
4596   Record.push_back(Str.size());
4597   Record.insert(Record.end(), Str.begin(), Str.end());
4598 }
4599 
4600 bool ASTWriter::PreparePathForOutput(SmallVectorImpl<char> &Path) {
4601   assert(Context && "should have context when outputting path");
4602 
4603   bool Changed =
4604       cleanPathForOutput(Context->getSourceManager().getFileManager(), Path);
4605 
4606   // Remove a prefix to make the path relative, if relevant.
4607   const char *PathBegin = Path.data();
4608   const char *PathPtr =
4609       adjustFilenameForRelocatableAST(PathBegin, BaseDirectory);
4610   if (PathPtr != PathBegin) {
4611     Path.erase(Path.begin(), Path.begin() + (PathPtr - PathBegin));
4612     Changed = true;
4613   }
4614 
4615   return Changed;
4616 }
4617 
4618 void ASTWriter::AddPath(StringRef Path, RecordDataImpl &Record) {
4619   SmallString<128> FilePath(Path);
4620   PreparePathForOutput(FilePath);
4621   AddString(FilePath, Record);
4622 }
4623 
4624 void ASTWriter::EmitRecordWithPath(unsigned Abbrev, RecordDataRef Record,
4625                                    StringRef Path) {
4626   SmallString<128> FilePath(Path);
4627   PreparePathForOutput(FilePath);
4628   Stream.EmitRecordWithBlob(Abbrev, Record, FilePath);
4629 }
4630 
4631 void ASTWriter::AddVersionTuple(const VersionTuple &Version,
4632                                 RecordDataImpl &Record) {
4633   Record.push_back(Version.getMajor());
4634   if (Optional<unsigned> Minor = Version.getMinor())
4635     Record.push_back(*Minor + 1);
4636   else
4637     Record.push_back(0);
4638   if (Optional<unsigned> Subminor = Version.getSubminor())
4639     Record.push_back(*Subminor + 1);
4640   else
4641     Record.push_back(0);
4642 }
4643 
4644 /// Note that the identifier II occurs at the given offset
4645 /// within the identifier table.
4646 void ASTWriter::SetIdentifierOffset(const IdentifierInfo *II, uint32_t Offset) {
4647   IdentID ID = IdentifierIDs[II];
4648   // Only store offsets new to this AST file. Other identifier names are looked
4649   // up earlier in the chain and thus don't need an offset.
4650   if (ID >= FirstIdentID)
4651     IdentifierOffsets[ID - FirstIdentID] = Offset;
4652 }
4653 
4654 /// Note that the selector Sel occurs at the given offset
4655 /// within the method pool/selector table.
4656 void ASTWriter::SetSelectorOffset(Selector Sel, uint32_t Offset) {
4657   unsigned ID = SelectorIDs[Sel];
4658   assert(ID && "Unknown selector");
4659   // Don't record offsets for selectors that are also available in a different
4660   // file.
4661   if (ID < FirstSelectorID)
4662     return;
4663   SelectorOffsets[ID - FirstSelectorID] = Offset;
4664 }
4665 
4666 ASTWriter::ASTWriter(llvm::BitstreamWriter &Stream,
4667                      SmallVectorImpl<char> &Buffer,
4668                      InMemoryModuleCache &ModuleCache,
4669                      ArrayRef<std::shared_ptr<ModuleFileExtension>> Extensions,
4670                      bool IncludeTimestamps)
4671     : Stream(Stream), Buffer(Buffer), ModuleCache(ModuleCache),
4672       IncludeTimestamps(IncludeTimestamps) {
4673   for (const auto &Ext : Extensions) {
4674     if (auto Writer = Ext->createExtensionWriter(*this))
4675       ModuleFileExtensionWriters.push_back(std::move(Writer));
4676   }
4677 }
4678 
4679 ASTWriter::~ASTWriter() {
4680   llvm::DeleteContainerSeconds(FileDeclIDs);
4681 }
4682 
4683 const LangOptions &ASTWriter::getLangOpts() const {
4684   assert(WritingAST && "can't determine lang opts when not writing AST");
4685   return Context->getLangOpts();
4686 }
4687 
4688 time_t ASTWriter::getTimestampForOutput(const FileEntry *E) const {
4689   return IncludeTimestamps ? E->getModificationTime() : 0;
4690 }
4691 
4692 ASTFileSignature ASTWriter::WriteAST(Sema &SemaRef,
4693                                      const std::string &OutputFile,
4694                                      Module *WritingModule, StringRef isysroot,
4695                                      bool hasErrors,
4696                                      bool ShouldCacheASTInMemory) {
4697   WritingAST = true;
4698 
4699   ASTHasCompilerErrors = hasErrors;
4700 
4701   // Emit the file header.
4702   Stream.Emit((unsigned)'C', 8);
4703   Stream.Emit((unsigned)'P', 8);
4704   Stream.Emit((unsigned)'C', 8);
4705   Stream.Emit((unsigned)'H', 8);
4706 
4707   WriteBlockInfoBlock();
4708 
4709   Context = &SemaRef.Context;
4710   PP = &SemaRef.PP;
4711   this->WritingModule = WritingModule;
4712   ASTFileSignature Signature =
4713       WriteASTCore(SemaRef, isysroot, OutputFile, WritingModule);
4714   Context = nullptr;
4715   PP = nullptr;
4716   this->WritingModule = nullptr;
4717   this->BaseDirectory.clear();
4718 
4719   WritingAST = false;
4720   if (ShouldCacheASTInMemory) {
4721     // Construct MemoryBuffer and update buffer manager.
4722     ModuleCache.addBuiltPCM(OutputFile,
4723                             llvm::MemoryBuffer::getMemBufferCopy(
4724                                 StringRef(Buffer.begin(), Buffer.size())));
4725   }
4726   return Signature;
4727 }
4728 
4729 template<typename Vector>
4730 static void AddLazyVectorDecls(ASTWriter &Writer, Vector &Vec,
4731                                ASTWriter::RecordData &Record) {
4732   for (typename Vector::iterator I = Vec.begin(nullptr, true), E = Vec.end();
4733        I != E; ++I) {
4734     Writer.AddDeclRef(*I, Record);
4735   }
4736 }
4737 
4738 ASTFileSignature ASTWriter::WriteASTCore(Sema &SemaRef, StringRef isysroot,
4739                                          const std::string &OutputFile,
4740                                          Module *WritingModule) {
4741   using namespace llvm;
4742 
4743   bool isModule = WritingModule != nullptr;
4744 
4745   // Make sure that the AST reader knows to finalize itself.
4746   if (Chain)
4747     Chain->finalizeForWriting();
4748 
4749   ASTContext &Context = SemaRef.Context;
4750   Preprocessor &PP = SemaRef.PP;
4751 
4752   // Set up predefined declaration IDs.
4753   auto RegisterPredefDecl = [&] (Decl *D, PredefinedDeclIDs ID) {
4754     if (D) {
4755       assert(D->isCanonicalDecl() && "predefined decl is not canonical");
4756       DeclIDs[D] = ID;
4757     }
4758   };
4759   RegisterPredefDecl(Context.getTranslationUnitDecl(),
4760                      PREDEF_DECL_TRANSLATION_UNIT_ID);
4761   RegisterPredefDecl(Context.ObjCIdDecl, PREDEF_DECL_OBJC_ID_ID);
4762   RegisterPredefDecl(Context.ObjCSelDecl, PREDEF_DECL_OBJC_SEL_ID);
4763   RegisterPredefDecl(Context.ObjCClassDecl, PREDEF_DECL_OBJC_CLASS_ID);
4764   RegisterPredefDecl(Context.ObjCProtocolClassDecl,
4765                      PREDEF_DECL_OBJC_PROTOCOL_ID);
4766   RegisterPredefDecl(Context.Int128Decl, PREDEF_DECL_INT_128_ID);
4767   RegisterPredefDecl(Context.UInt128Decl, PREDEF_DECL_UNSIGNED_INT_128_ID);
4768   RegisterPredefDecl(Context.ObjCInstanceTypeDecl,
4769                      PREDEF_DECL_OBJC_INSTANCETYPE_ID);
4770   RegisterPredefDecl(Context.BuiltinVaListDecl, PREDEF_DECL_BUILTIN_VA_LIST_ID);
4771   RegisterPredefDecl(Context.VaListTagDecl, PREDEF_DECL_VA_LIST_TAG);
4772   RegisterPredefDecl(Context.BuiltinMSVaListDecl,
4773                      PREDEF_DECL_BUILTIN_MS_VA_LIST_ID);
4774   RegisterPredefDecl(Context.ExternCContext, PREDEF_DECL_EXTERN_C_CONTEXT_ID);
4775   RegisterPredefDecl(Context.MakeIntegerSeqDecl,
4776                      PREDEF_DECL_MAKE_INTEGER_SEQ_ID);
4777   RegisterPredefDecl(Context.CFConstantStringTypeDecl,
4778                      PREDEF_DECL_CF_CONSTANT_STRING_ID);
4779   RegisterPredefDecl(Context.CFConstantStringTagDecl,
4780                      PREDEF_DECL_CF_CONSTANT_STRING_TAG_ID);
4781   RegisterPredefDecl(Context.TypePackElementDecl,
4782                      PREDEF_DECL_TYPE_PACK_ELEMENT_ID);
4783 
4784   // Build a record containing all of the tentative definitions in this file, in
4785   // TentativeDefinitions order.  Generally, this record will be empty for
4786   // headers.
4787   RecordData TentativeDefinitions;
4788   AddLazyVectorDecls(*this, SemaRef.TentativeDefinitions, TentativeDefinitions);
4789 
4790   // Build a record containing all of the file scoped decls in this file.
4791   RecordData UnusedFileScopedDecls;
4792   if (!isModule)
4793     AddLazyVectorDecls(*this, SemaRef.UnusedFileScopedDecls,
4794                        UnusedFileScopedDecls);
4795 
4796   // Build a record containing all of the delegating constructors we still need
4797   // to resolve.
4798   RecordData DelegatingCtorDecls;
4799   if (!isModule)
4800     AddLazyVectorDecls(*this, SemaRef.DelegatingCtorDecls, DelegatingCtorDecls);
4801 
4802   // Write the set of weak, undeclared identifiers. We always write the
4803   // entire table, since later PCH files in a PCH chain are only interested in
4804   // the results at the end of the chain.
4805   RecordData WeakUndeclaredIdentifiers;
4806   for (auto &WeakUndeclaredIdentifier : SemaRef.WeakUndeclaredIdentifiers) {
4807     IdentifierInfo *II = WeakUndeclaredIdentifier.first;
4808     WeakInfo &WI = WeakUndeclaredIdentifier.second;
4809     AddIdentifierRef(II, WeakUndeclaredIdentifiers);
4810     AddIdentifierRef(WI.getAlias(), WeakUndeclaredIdentifiers);
4811     AddSourceLocation(WI.getLocation(), WeakUndeclaredIdentifiers);
4812     WeakUndeclaredIdentifiers.push_back(WI.getUsed());
4813   }
4814 
4815   // Build a record containing all of the ext_vector declarations.
4816   RecordData ExtVectorDecls;
4817   AddLazyVectorDecls(*this, SemaRef.ExtVectorDecls, ExtVectorDecls);
4818 
4819   // Build a record containing all of the VTable uses information.
4820   RecordData VTableUses;
4821   if (!SemaRef.VTableUses.empty()) {
4822     for (unsigned I = 0, N = SemaRef.VTableUses.size(); I != N; ++I) {
4823       AddDeclRef(SemaRef.VTableUses[I].first, VTableUses);
4824       AddSourceLocation(SemaRef.VTableUses[I].second, VTableUses);
4825       VTableUses.push_back(SemaRef.VTablesUsed[SemaRef.VTableUses[I].first]);
4826     }
4827   }
4828 
4829   // Build a record containing all of the UnusedLocalTypedefNameCandidates.
4830   RecordData UnusedLocalTypedefNameCandidates;
4831   for (const TypedefNameDecl *TD : SemaRef.UnusedLocalTypedefNameCandidates)
4832     AddDeclRef(TD, UnusedLocalTypedefNameCandidates);
4833 
4834   // Build a record containing all of pending implicit instantiations.
4835   RecordData PendingInstantiations;
4836   for (const auto &I : SemaRef.PendingInstantiations) {
4837     AddDeclRef(I.first, PendingInstantiations);
4838     AddSourceLocation(I.second, PendingInstantiations);
4839   }
4840   assert(SemaRef.PendingLocalImplicitInstantiations.empty() &&
4841          "There are local ones at end of translation unit!");
4842 
4843   // Build a record containing some declaration references.
4844   RecordData SemaDeclRefs;
4845   if (SemaRef.StdNamespace || SemaRef.StdBadAlloc || SemaRef.StdAlignValT) {
4846     AddDeclRef(SemaRef.getStdNamespace(), SemaDeclRefs);
4847     AddDeclRef(SemaRef.getStdBadAlloc(), SemaDeclRefs);
4848     AddDeclRef(SemaRef.getStdAlignValT(), SemaDeclRefs);
4849   }
4850 
4851   RecordData CUDASpecialDeclRefs;
4852   if (Context.getcudaConfigureCallDecl()) {
4853     AddDeclRef(Context.getcudaConfigureCallDecl(), CUDASpecialDeclRefs);
4854   }
4855 
4856   // Build a record containing all of the known namespaces.
4857   RecordData KnownNamespaces;
4858   for (const auto &I : SemaRef.KnownNamespaces) {
4859     if (!I.second)
4860       AddDeclRef(I.first, KnownNamespaces);
4861   }
4862 
4863   // Build a record of all used, undefined objects that require definitions.
4864   RecordData UndefinedButUsed;
4865 
4866   SmallVector<std::pair<NamedDecl *, SourceLocation>, 16> Undefined;
4867   SemaRef.getUndefinedButUsed(Undefined);
4868   for (const auto &I : Undefined) {
4869     AddDeclRef(I.first, UndefinedButUsed);
4870     AddSourceLocation(I.second, UndefinedButUsed);
4871   }
4872 
4873   // Build a record containing all delete-expressions that we would like to
4874   // analyze later in AST.
4875   RecordData DeleteExprsToAnalyze;
4876 
4877   if (!isModule) {
4878     for (const auto &DeleteExprsInfo :
4879          SemaRef.getMismatchingDeleteExpressions()) {
4880       AddDeclRef(DeleteExprsInfo.first, DeleteExprsToAnalyze);
4881       DeleteExprsToAnalyze.push_back(DeleteExprsInfo.second.size());
4882       for (const auto &DeleteLoc : DeleteExprsInfo.second) {
4883         AddSourceLocation(DeleteLoc.first, DeleteExprsToAnalyze);
4884         DeleteExprsToAnalyze.push_back(DeleteLoc.second);
4885       }
4886     }
4887   }
4888 
4889   // Write the control block
4890   WriteControlBlock(PP, Context, isysroot, OutputFile);
4891 
4892   // Write the remaining AST contents.
4893   Stream.EnterSubblock(AST_BLOCK_ID, 5);
4894 
4895   // This is so that older clang versions, before the introduction
4896   // of the control block, can read and reject the newer PCH format.
4897   {
4898     RecordData Record = {VERSION_MAJOR};
4899     Stream.EmitRecord(METADATA_OLD_FORMAT, Record);
4900   }
4901 
4902   // Create a lexical update block containing all of the declarations in the
4903   // translation unit that do not come from other AST files.
4904   const TranslationUnitDecl *TU = Context.getTranslationUnitDecl();
4905   SmallVector<uint32_t, 128> NewGlobalKindDeclPairs;
4906   for (const auto *D : TU->noload_decls()) {
4907     if (!D->isFromASTFile()) {
4908       NewGlobalKindDeclPairs.push_back(D->getKind());
4909       NewGlobalKindDeclPairs.push_back(GetDeclRef(D));
4910     }
4911   }
4912 
4913   auto Abv = std::make_shared<BitCodeAbbrev>();
4914   Abv->Add(llvm::BitCodeAbbrevOp(TU_UPDATE_LEXICAL));
4915   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Blob));
4916   unsigned TuUpdateLexicalAbbrev = Stream.EmitAbbrev(std::move(Abv));
4917   {
4918     RecordData::value_type Record[] = {TU_UPDATE_LEXICAL};
4919     Stream.EmitRecordWithBlob(TuUpdateLexicalAbbrev, Record,
4920                               bytes(NewGlobalKindDeclPairs));
4921   }
4922 
4923   // And a visible updates block for the translation unit.
4924   Abv = std::make_shared<BitCodeAbbrev>();
4925   Abv->Add(llvm::BitCodeAbbrevOp(UPDATE_VISIBLE));
4926   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::VBR, 6));
4927   Abv->Add(llvm::BitCodeAbbrevOp(llvm::BitCodeAbbrevOp::Blob));
4928   UpdateVisibleAbbrev = Stream.EmitAbbrev(std::move(Abv));
4929   WriteDeclContextVisibleUpdate(TU);
4930 
4931   // If we have any extern "C" names, write out a visible update for them.
4932   if (Context.ExternCContext)
4933     WriteDeclContextVisibleUpdate(Context.ExternCContext);
4934 
4935   // If the translation unit has an anonymous namespace, and we don't already
4936   // have an update block for it, write it as an update block.
4937   // FIXME: Why do we not do this if there's already an update block?
4938   if (NamespaceDecl *NS = TU->getAnonymousNamespace()) {
4939     ASTWriter::UpdateRecord &Record = DeclUpdates[TU];
4940     if (Record.empty())
4941       Record.push_back(DeclUpdate(UPD_CXX_ADDED_ANONYMOUS_NAMESPACE, NS));
4942   }
4943 
4944   // Add update records for all mangling numbers and static local numbers.
4945   // These aren't really update records, but this is a convenient way of
4946   // tagging this rare extra data onto the declarations.
4947   for (const auto &Number : Context.MangleNumbers)
4948     if (!Number.first->isFromASTFile())
4949       DeclUpdates[Number.first].push_back(DeclUpdate(UPD_MANGLING_NUMBER,
4950                                                      Number.second));
4951   for (const auto &Number : Context.StaticLocalNumbers)
4952     if (!Number.first->isFromASTFile())
4953       DeclUpdates[Number.first].push_back(DeclUpdate(UPD_STATIC_LOCAL_NUMBER,
4954                                                      Number.second));
4955 
4956   // Make sure visible decls, added to DeclContexts previously loaded from
4957   // an AST file, are registered for serialization. Likewise for template
4958   // specializations added to imported templates.
4959   for (const auto *I : DeclsToEmitEvenIfUnreferenced) {
4960     GetDeclRef(I);
4961   }
4962 
4963   // Make sure all decls associated with an identifier are registered for
4964   // serialization, if we're storing decls with identifiers.
4965   if (!WritingModule || !getLangOpts().CPlusPlus) {
4966     llvm::SmallVector<const IdentifierInfo*, 256> IIs;
4967     for (const auto &ID : PP.getIdentifierTable()) {
4968       const IdentifierInfo *II = ID.second;
4969       if (!Chain || !II->isFromAST() || II->hasChangedSinceDeserialization())
4970         IIs.push_back(II);
4971     }
4972     // Sort the identifiers to visit based on their name.
4973     llvm::sort(IIs, llvm::deref<std::less<>>());
4974     for (const IdentifierInfo *II : IIs) {
4975       for (IdentifierResolver::iterator D = SemaRef.IdResolver.begin(II),
4976                                      DEnd = SemaRef.IdResolver.end();
4977            D != DEnd; ++D) {
4978         GetDeclRef(*D);
4979       }
4980     }
4981   }
4982 
4983   // For method pool in the module, if it contains an entry for a selector,
4984   // the entry should be complete, containing everything introduced by that
4985   // module and all modules it imports. It's possible that the entry is out of
4986   // date, so we need to pull in the new content here.
4987 
4988   // It's possible that updateOutOfDateSelector can update SelectorIDs. To be
4989   // safe, we copy all selectors out.
4990   llvm::SmallVector<Selector, 256> AllSelectors;
4991   for (auto &SelectorAndID : SelectorIDs)
4992     AllSelectors.push_back(SelectorAndID.first);
4993   for (auto &Selector : AllSelectors)
4994     SemaRef.updateOutOfDateSelector(Selector);
4995 
4996   // Form the record of special types.
4997   RecordData SpecialTypes;
4998   AddTypeRef(Context.getRawCFConstantStringType(), SpecialTypes);
4999   AddTypeRef(Context.getFILEType(), SpecialTypes);
5000   AddTypeRef(Context.getjmp_bufType(), SpecialTypes);
5001   AddTypeRef(Context.getsigjmp_bufType(), SpecialTypes);
5002   AddTypeRef(Context.ObjCIdRedefinitionType, SpecialTypes);
5003   AddTypeRef(Context.ObjCClassRedefinitionType, SpecialTypes);
5004   AddTypeRef(Context.ObjCSelRedefinitionType, SpecialTypes);
5005   AddTypeRef(Context.getucontext_tType(), SpecialTypes);
5006 
5007   if (Chain) {
5008     // Write the mapping information describing our module dependencies and how
5009     // each of those modules were mapped into our own offset/ID space, so that
5010     // the reader can build the appropriate mapping to its own offset/ID space.
5011     // The map consists solely of a blob with the following format:
5012     // *(module-kind:i8
5013     //   module-name-len:i16 module-name:len*i8
5014     //   source-location-offset:i32
5015     //   identifier-id:i32
5016     //   preprocessed-entity-id:i32
5017     //   macro-definition-id:i32
5018     //   submodule-id:i32
5019     //   selector-id:i32
5020     //   declaration-id:i32
5021     //   c++-base-specifiers-id:i32
5022     //   type-id:i32)
5023     //
5024     // module-kind is the ModuleKind enum value. If it is MK_PrebuiltModule or
5025     // MK_ExplicitModule, then the module-name is the module name. Otherwise,
5026     // it is the module file name.
5027     auto Abbrev = std::make_shared<BitCodeAbbrev>();
5028     Abbrev->Add(BitCodeAbbrevOp(MODULE_OFFSET_MAP));
5029     Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
5030     unsigned ModuleOffsetMapAbbrev = Stream.EmitAbbrev(std::move(Abbrev));
5031     SmallString<2048> Buffer;
5032     {
5033       llvm::raw_svector_ostream Out(Buffer);
5034       for (ModuleFile &M : Chain->ModuleMgr) {
5035         using namespace llvm::support;
5036 
5037         endian::Writer LE(Out, little);
5038         LE.write<uint8_t>(static_cast<uint8_t>(M.Kind));
5039         StringRef Name =
5040           M.Kind == MK_PrebuiltModule || M.Kind == MK_ExplicitModule
5041           ? M.ModuleName
5042           : M.FileName;
5043         LE.write<uint16_t>(Name.size());
5044         Out.write(Name.data(), Name.size());
5045 
5046         // Note: if a base ID was uint max, it would not be possible to load
5047         // another module after it or have more than one entity inside it.
5048         uint32_t None = std::numeric_limits<uint32_t>::max();
5049 
5050         auto writeBaseIDOrNone = [&](uint32_t BaseID, bool ShouldWrite) {
5051           assert(BaseID < std::numeric_limits<uint32_t>::max() && "base id too high");
5052           if (ShouldWrite)
5053             LE.write<uint32_t>(BaseID);
5054           else
5055             LE.write<uint32_t>(None);
5056         };
5057 
5058         // These values should be unique within a chain, since they will be read
5059         // as keys into ContinuousRangeMaps.
5060         writeBaseIDOrNone(M.SLocEntryBaseOffset, M.LocalNumSLocEntries);
5061         writeBaseIDOrNone(M.BaseIdentifierID, M.LocalNumIdentifiers);
5062         writeBaseIDOrNone(M.BaseMacroID, M.LocalNumMacros);
5063         writeBaseIDOrNone(M.BasePreprocessedEntityID,
5064                           M.NumPreprocessedEntities);
5065         writeBaseIDOrNone(M.BaseSubmoduleID, M.LocalNumSubmodules);
5066         writeBaseIDOrNone(M.BaseSelectorID, M.LocalNumSelectors);
5067         writeBaseIDOrNone(M.BaseDeclID, M.LocalNumDecls);
5068         writeBaseIDOrNone(M.BaseTypeIndex, M.LocalNumTypes);
5069       }
5070     }
5071     RecordData::value_type Record[] = {MODULE_OFFSET_MAP};
5072     Stream.EmitRecordWithBlob(ModuleOffsetMapAbbrev, Record,
5073                               Buffer.data(), Buffer.size());
5074   }
5075 
5076   RecordData DeclUpdatesOffsetsRecord;
5077 
5078   // Keep writing types, declarations, and declaration update records
5079   // until we've emitted all of them.
5080   Stream.EnterSubblock(DECLTYPES_BLOCK_ID, /*bits for abbreviations*/5);
5081   WriteTypeAbbrevs();
5082   WriteDeclAbbrevs();
5083   do {
5084     WriteDeclUpdatesBlocks(DeclUpdatesOffsetsRecord);
5085     while (!DeclTypesToEmit.empty()) {
5086       DeclOrType DOT = DeclTypesToEmit.front();
5087       DeclTypesToEmit.pop();
5088       if (DOT.isType())
5089         WriteType(DOT.getType());
5090       else
5091         WriteDecl(Context, DOT.getDecl());
5092     }
5093   } while (!DeclUpdates.empty());
5094   Stream.ExitBlock();
5095 
5096   DoneWritingDeclsAndTypes = true;
5097 
5098   // These things can only be done once we've written out decls and types.
5099   WriteTypeDeclOffsets();
5100   if (!DeclUpdatesOffsetsRecord.empty())
5101     Stream.EmitRecord(DECL_UPDATE_OFFSETS, DeclUpdatesOffsetsRecord);
5102   WriteFileDeclIDsMap();
5103   WriteSourceManagerBlock(Context.getSourceManager(), PP);
5104   WriteComments();
5105   WritePreprocessor(PP, isModule);
5106   WriteHeaderSearch(PP.getHeaderSearchInfo());
5107   WriteSelectors(SemaRef);
5108   WriteReferencedSelectorsPool(SemaRef);
5109   WriteLateParsedTemplates(SemaRef);
5110   WriteIdentifierTable(PP, SemaRef.IdResolver, isModule);
5111   WriteFPPragmaOptions(SemaRef.getFPOptions());
5112   WriteOpenCLExtensions(SemaRef);
5113   WriteOpenCLExtensionTypes(SemaRef);
5114   WriteCUDAPragmas(SemaRef);
5115 
5116   // If we're emitting a module, write out the submodule information.
5117   if (WritingModule)
5118     WriteSubmodules(WritingModule);
5119 
5120   // We need to have information about submodules to correctly deserialize
5121   // decls from OpenCLExtensionDecls block
5122   WriteOpenCLExtensionDecls(SemaRef);
5123 
5124   Stream.EmitRecord(SPECIAL_TYPES, SpecialTypes);
5125 
5126   // Write the record containing external, unnamed definitions.
5127   if (!EagerlyDeserializedDecls.empty())
5128     Stream.EmitRecord(EAGERLY_DESERIALIZED_DECLS, EagerlyDeserializedDecls);
5129 
5130   if (!ModularCodegenDecls.empty())
5131     Stream.EmitRecord(MODULAR_CODEGEN_DECLS, ModularCodegenDecls);
5132 
5133   // Write the record containing tentative definitions.
5134   if (!TentativeDefinitions.empty())
5135     Stream.EmitRecord(TENTATIVE_DEFINITIONS, TentativeDefinitions);
5136 
5137   // Write the record containing unused file scoped decls.
5138   if (!UnusedFileScopedDecls.empty())
5139     Stream.EmitRecord(UNUSED_FILESCOPED_DECLS, UnusedFileScopedDecls);
5140 
5141   // Write the record containing weak undeclared identifiers.
5142   if (!WeakUndeclaredIdentifiers.empty())
5143     Stream.EmitRecord(WEAK_UNDECLARED_IDENTIFIERS,
5144                       WeakUndeclaredIdentifiers);
5145 
5146   // Write the record containing ext_vector type names.
5147   if (!ExtVectorDecls.empty())
5148     Stream.EmitRecord(EXT_VECTOR_DECLS, ExtVectorDecls);
5149 
5150   // Write the record containing VTable uses information.
5151   if (!VTableUses.empty())
5152     Stream.EmitRecord(VTABLE_USES, VTableUses);
5153 
5154   // Write the record containing potentially unused local typedefs.
5155   if (!UnusedLocalTypedefNameCandidates.empty())
5156     Stream.EmitRecord(UNUSED_LOCAL_TYPEDEF_NAME_CANDIDATES,
5157                       UnusedLocalTypedefNameCandidates);
5158 
5159   // Write the record containing pending implicit instantiations.
5160   if (!PendingInstantiations.empty())
5161     Stream.EmitRecord(PENDING_IMPLICIT_INSTANTIATIONS, PendingInstantiations);
5162 
5163   // Write the record containing declaration references of Sema.
5164   if (!SemaDeclRefs.empty())
5165     Stream.EmitRecord(SEMA_DECL_REFS, SemaDeclRefs);
5166 
5167   // Write the record containing CUDA-specific declaration references.
5168   if (!CUDASpecialDeclRefs.empty())
5169     Stream.EmitRecord(CUDA_SPECIAL_DECL_REFS, CUDASpecialDeclRefs);
5170 
5171   // Write the delegating constructors.
5172   if (!DelegatingCtorDecls.empty())
5173     Stream.EmitRecord(DELEGATING_CTORS, DelegatingCtorDecls);
5174 
5175   // Write the known namespaces.
5176   if (!KnownNamespaces.empty())
5177     Stream.EmitRecord(KNOWN_NAMESPACES, KnownNamespaces);
5178 
5179   // Write the undefined internal functions and variables, and inline functions.
5180   if (!UndefinedButUsed.empty())
5181     Stream.EmitRecord(UNDEFINED_BUT_USED, UndefinedButUsed);
5182 
5183   if (!DeleteExprsToAnalyze.empty())
5184     Stream.EmitRecord(DELETE_EXPRS_TO_ANALYZE, DeleteExprsToAnalyze);
5185 
5186   // Write the visible updates to DeclContexts.
5187   for (auto *DC : UpdatedDeclContexts)
5188     WriteDeclContextVisibleUpdate(DC);
5189 
5190   if (!WritingModule) {
5191     // Write the submodules that were imported, if any.
5192     struct ModuleInfo {
5193       uint64_t ID;
5194       Module *M;
5195       ModuleInfo(uint64_t ID, Module *M) : ID(ID), M(M) {}
5196     };
5197     llvm::SmallVector<ModuleInfo, 64> Imports;
5198     for (const auto *I : Context.local_imports()) {
5199       assert(SubmoduleIDs.find(I->getImportedModule()) != SubmoduleIDs.end());
5200       Imports.push_back(ModuleInfo(SubmoduleIDs[I->getImportedModule()],
5201                          I->getImportedModule()));
5202     }
5203 
5204     if (!Imports.empty()) {
5205       auto Cmp = [](const ModuleInfo &A, const ModuleInfo &B) {
5206         return A.ID < B.ID;
5207       };
5208       auto Eq = [](const ModuleInfo &A, const ModuleInfo &B) {
5209         return A.ID == B.ID;
5210       };
5211 
5212       // Sort and deduplicate module IDs.
5213       llvm::sort(Imports, Cmp);
5214       Imports.erase(std::unique(Imports.begin(), Imports.end(), Eq),
5215                     Imports.end());
5216 
5217       RecordData ImportedModules;
5218       for (const auto &Import : Imports) {
5219         ImportedModules.push_back(Import.ID);
5220         // FIXME: If the module has macros imported then later has declarations
5221         // imported, this location won't be the right one as a location for the
5222         // declaration imports.
5223         AddSourceLocation(PP.getModuleImportLoc(Import.M), ImportedModules);
5224       }
5225 
5226       Stream.EmitRecord(IMPORTED_MODULES, ImportedModules);
5227     }
5228   }
5229 
5230   WriteObjCCategories();
5231   if(!WritingModule) {
5232     WriteOptimizePragmaOptions(SemaRef);
5233     WriteMSStructPragmaOptions(SemaRef);
5234     WriteMSPointersToMembersPragmaOptions(SemaRef);
5235   }
5236   WritePackPragmaOptions(SemaRef);
5237 
5238   // Some simple statistics
5239   RecordData::value_type Record[] = {
5240       NumStatements, NumMacros, NumLexicalDeclContexts, NumVisibleDeclContexts};
5241   Stream.EmitRecord(STATISTICS, Record);
5242   Stream.ExitBlock();
5243 
5244   // Write the module file extension blocks.
5245   for (const auto &ExtWriter : ModuleFileExtensionWriters)
5246     WriteModuleFileExtension(SemaRef, *ExtWriter);
5247 
5248   return writeUnhashedControlBlock(PP, Context);
5249 }
5250 
5251 void ASTWriter::WriteDeclUpdatesBlocks(RecordDataImpl &OffsetsRecord) {
5252   if (DeclUpdates.empty())
5253     return;
5254 
5255   DeclUpdateMap LocalUpdates;
5256   LocalUpdates.swap(DeclUpdates);
5257 
5258   for (auto &DeclUpdate : LocalUpdates) {
5259     const Decl *D = DeclUpdate.first;
5260 
5261     bool HasUpdatedBody = false;
5262     RecordData RecordData;
5263     ASTRecordWriter Record(*this, RecordData);
5264     for (auto &Update : DeclUpdate.second) {
5265       DeclUpdateKind Kind = (DeclUpdateKind)Update.getKind();
5266 
5267       // An updated body is emitted last, so that the reader doesn't need
5268       // to skip over the lazy body to reach statements for other records.
5269       if (Kind == UPD_CXX_ADDED_FUNCTION_DEFINITION)
5270         HasUpdatedBody = true;
5271       else
5272         Record.push_back(Kind);
5273 
5274       switch (Kind) {
5275       case UPD_CXX_ADDED_IMPLICIT_MEMBER:
5276       case UPD_CXX_ADDED_TEMPLATE_SPECIALIZATION:
5277       case UPD_CXX_ADDED_ANONYMOUS_NAMESPACE:
5278         assert(Update.getDecl() && "no decl to add?");
5279         Record.push_back(GetDeclRef(Update.getDecl()));
5280         break;
5281 
5282       case UPD_CXX_ADDED_FUNCTION_DEFINITION:
5283         break;
5284 
5285       case UPD_CXX_POINT_OF_INSTANTIATION:
5286         // FIXME: Do we need to also save the template specialization kind here?
5287         Record.AddSourceLocation(Update.getLoc());
5288         break;
5289 
5290       case UPD_CXX_ADDED_VAR_DEFINITION: {
5291         const VarDecl *VD = cast<VarDecl>(D);
5292         Record.push_back(VD->isInline());
5293         Record.push_back(VD->isInlineSpecified());
5294         if (VD->getInit()) {
5295           Record.push_back(!VD->isInitKnownICE() ? 1
5296                                                  : (VD->isInitICE() ? 3 : 2));
5297           Record.AddStmt(const_cast<Expr*>(VD->getInit()));
5298         } else {
5299           Record.push_back(0);
5300         }
5301         break;
5302       }
5303 
5304       case UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT:
5305         Record.AddStmt(const_cast<Expr *>(
5306             cast<ParmVarDecl>(Update.getDecl())->getDefaultArg()));
5307         break;
5308 
5309       case UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER:
5310         Record.AddStmt(
5311             cast<FieldDecl>(Update.getDecl())->getInClassInitializer());
5312         break;
5313 
5314       case UPD_CXX_INSTANTIATED_CLASS_DEFINITION: {
5315         auto *RD = cast<CXXRecordDecl>(D);
5316         UpdatedDeclContexts.insert(RD->getPrimaryContext());
5317         Record.push_back(RD->isParamDestroyedInCallee());
5318         Record.push_back(RD->getArgPassingRestrictions());
5319         Record.AddCXXDefinitionData(RD);
5320         Record.AddOffset(WriteDeclContextLexicalBlock(
5321             *Context, const_cast<CXXRecordDecl *>(RD)));
5322 
5323         // This state is sometimes updated by template instantiation, when we
5324         // switch from the specialization referring to the template declaration
5325         // to it referring to the template definition.
5326         if (auto *MSInfo = RD->getMemberSpecializationInfo()) {
5327           Record.push_back(MSInfo->getTemplateSpecializationKind());
5328           Record.AddSourceLocation(MSInfo->getPointOfInstantiation());
5329         } else {
5330           auto *Spec = cast<ClassTemplateSpecializationDecl>(RD);
5331           Record.push_back(Spec->getTemplateSpecializationKind());
5332           Record.AddSourceLocation(Spec->getPointOfInstantiation());
5333 
5334           // The instantiation might have been resolved to a partial
5335           // specialization. If so, record which one.
5336           auto From = Spec->getInstantiatedFrom();
5337           if (auto PartialSpec =
5338                 From.dyn_cast<ClassTemplatePartialSpecializationDecl*>()) {
5339             Record.push_back(true);
5340             Record.AddDeclRef(PartialSpec);
5341             Record.AddTemplateArgumentList(
5342                 &Spec->getTemplateInstantiationArgs());
5343           } else {
5344             Record.push_back(false);
5345           }
5346         }
5347         Record.push_back(RD->getTagKind());
5348         Record.AddSourceLocation(RD->getLocation());
5349         Record.AddSourceLocation(RD->getBeginLoc());
5350         Record.AddSourceRange(RD->getBraceRange());
5351 
5352         // Instantiation may change attributes; write them all out afresh.
5353         Record.push_back(D->hasAttrs());
5354         if (D->hasAttrs())
5355           Record.AddAttributes(D->getAttrs());
5356 
5357         // FIXME: Ensure we don't get here for explicit instantiations.
5358         break;
5359       }
5360 
5361       case UPD_CXX_RESOLVED_DTOR_DELETE:
5362         Record.AddDeclRef(Update.getDecl());
5363         Record.AddStmt(cast<CXXDestructorDecl>(D)->getOperatorDeleteThisArg());
5364         break;
5365 
5366       case UPD_CXX_RESOLVED_EXCEPTION_SPEC:
5367         addExceptionSpec(
5368             cast<FunctionDecl>(D)->getType()->castAs<FunctionProtoType>(),
5369             Record);
5370         break;
5371 
5372       case UPD_CXX_DEDUCED_RETURN_TYPE:
5373         Record.push_back(GetOrCreateTypeID(Update.getType()));
5374         break;
5375 
5376       case UPD_DECL_MARKED_USED:
5377         break;
5378 
5379       case UPD_MANGLING_NUMBER:
5380       case UPD_STATIC_LOCAL_NUMBER:
5381         Record.push_back(Update.getNumber());
5382         break;
5383 
5384       case UPD_DECL_MARKED_OPENMP_THREADPRIVATE:
5385         Record.AddSourceRange(
5386             D->getAttr<OMPThreadPrivateDeclAttr>()->getRange());
5387         break;
5388 
5389       case UPD_DECL_MARKED_OPENMP_ALLOCATE: {
5390         auto *A = D->getAttr<OMPAllocateDeclAttr>();
5391         Record.push_back(A->getAllocatorType());
5392         Record.AddStmt(A->getAllocator());
5393         Record.AddSourceRange(A->getRange());
5394         break;
5395       }
5396 
5397       case UPD_DECL_MARKED_OPENMP_DECLARETARGET:
5398         Record.push_back(D->getAttr<OMPDeclareTargetDeclAttr>()->getMapType());
5399         Record.AddSourceRange(
5400             D->getAttr<OMPDeclareTargetDeclAttr>()->getRange());
5401         break;
5402 
5403       case UPD_DECL_EXPORTED:
5404         Record.push_back(getSubmoduleID(Update.getModule()));
5405         break;
5406 
5407       case UPD_ADDED_ATTR_TO_RECORD:
5408         Record.AddAttributes(llvm::makeArrayRef(Update.getAttr()));
5409         break;
5410       }
5411     }
5412 
5413     if (HasUpdatedBody) {
5414       const auto *Def = cast<FunctionDecl>(D);
5415       Record.push_back(UPD_CXX_ADDED_FUNCTION_DEFINITION);
5416       Record.push_back(Def->isInlined());
5417       Record.AddSourceLocation(Def->getInnerLocStart());
5418       Record.AddFunctionDefinition(Def);
5419     }
5420 
5421     OffsetsRecord.push_back(GetDeclRef(D));
5422     OffsetsRecord.push_back(Record.Emit(DECL_UPDATES));
5423   }
5424 }
5425 
5426 void ASTWriter::AddSourceLocation(SourceLocation Loc, RecordDataImpl &Record) {
5427   uint32_t Raw = Loc.getRawEncoding();
5428   Record.push_back((Raw << 1) | (Raw >> 31));
5429 }
5430 
5431 void ASTWriter::AddSourceRange(SourceRange Range, RecordDataImpl &Record) {
5432   AddSourceLocation(Range.getBegin(), Record);
5433   AddSourceLocation(Range.getEnd(), Record);
5434 }
5435 
5436 void ASTRecordWriter::AddAPInt(const llvm::APInt &Value) {
5437   Record->push_back(Value.getBitWidth());
5438   const uint64_t *Words = Value.getRawData();
5439   Record->append(Words, Words + Value.getNumWords());
5440 }
5441 
5442 void ASTRecordWriter::AddAPSInt(const llvm::APSInt &Value) {
5443   Record->push_back(Value.isUnsigned());
5444   AddAPInt(Value);
5445 }
5446 
5447 void ASTRecordWriter::AddAPFloat(const llvm::APFloat &Value) {
5448   AddAPInt(Value.bitcastToAPInt());
5449 }
5450 
5451 static void WriteFixedPointSemantics(ASTRecordWriter &Record,
5452                                      FixedPointSemantics FPSema) {
5453   Record.push_back(FPSema.getWidth());
5454   Record.push_back(FPSema.getScale());
5455   Record.push_back(FPSema.isSigned() | FPSema.isSaturated() << 1 |
5456                    FPSema.hasUnsignedPadding() << 2);
5457 }
5458 
5459 void ASTRecordWriter::AddAPValue(const APValue &Value) {
5460   APValue::ValueKind Kind = Value.getKind();
5461   push_back(static_cast<uint64_t>(Kind));
5462   switch (Kind) {
5463   case APValue::None:
5464   case APValue::Indeterminate:
5465     return;
5466   case APValue::Int:
5467     AddAPSInt(Value.getInt());
5468     return;
5469   case APValue::Float:
5470     push_back(static_cast<uint64_t>(
5471         llvm::APFloatBase::SemanticsToEnum(Value.getFloat().getSemantics())));
5472     AddAPFloat(Value.getFloat());
5473     return;
5474   case APValue::FixedPoint: {
5475     WriteFixedPointSemantics(*this, Value.getFixedPoint().getSemantics());
5476     AddAPSInt(Value.getFixedPoint().getValue());
5477     return;
5478   }
5479   case APValue::ComplexInt: {
5480     AddAPSInt(Value.getComplexIntReal());
5481     AddAPSInt(Value.getComplexIntImag());
5482     return;
5483   }
5484   case APValue::ComplexFloat: {
5485     push_back(static_cast<uint64_t>(llvm::APFloatBase::SemanticsToEnum(
5486         Value.getComplexFloatReal().getSemantics())));
5487     AddAPFloat(Value.getComplexFloatReal());
5488     push_back(static_cast<uint64_t>(llvm::APFloatBase::SemanticsToEnum(
5489         Value.getComplexFloatImag().getSemantics())));
5490     AddAPFloat(Value.getComplexFloatImag());
5491     return;
5492   }
5493   case APValue::LValue:
5494   case APValue::Vector:
5495   case APValue::Array:
5496   case APValue::Struct:
5497   case APValue::Union:
5498   case APValue::MemberPointer:
5499   case APValue::AddrLabelDiff:
5500     // TODO : Handle all these APValue::ValueKind.
5501     return;
5502   }
5503   llvm_unreachable("Invalid APValue::ValueKind");
5504 }
5505 
5506 void ASTWriter::AddIdentifierRef(const IdentifierInfo *II, RecordDataImpl &Record) {
5507   Record.push_back(getIdentifierRef(II));
5508 }
5509 
5510 IdentID ASTWriter::getIdentifierRef(const IdentifierInfo *II) {
5511   if (!II)
5512     return 0;
5513 
5514   IdentID &ID = IdentifierIDs[II];
5515   if (ID == 0)
5516     ID = NextIdentID++;
5517   return ID;
5518 }
5519 
5520 MacroID ASTWriter::getMacroRef(MacroInfo *MI, const IdentifierInfo *Name) {
5521   // Don't emit builtin macros like __LINE__ to the AST file unless they
5522   // have been redefined by the header (in which case they are not
5523   // isBuiltinMacro).
5524   if (!MI || MI->isBuiltinMacro())
5525     return 0;
5526 
5527   MacroID &ID = MacroIDs[MI];
5528   if (ID == 0) {
5529     ID = NextMacroID++;
5530     MacroInfoToEmitData Info = { Name, MI, ID };
5531     MacroInfosToEmit.push_back(Info);
5532   }
5533   return ID;
5534 }
5535 
5536 MacroID ASTWriter::getMacroID(MacroInfo *MI) {
5537   if (!MI || MI->isBuiltinMacro())
5538     return 0;
5539 
5540   assert(MacroIDs.find(MI) != MacroIDs.end() && "Macro not emitted!");
5541   return MacroIDs[MI];
5542 }
5543 
5544 uint64_t ASTWriter::getMacroDirectivesOffset(const IdentifierInfo *Name) {
5545   return IdentMacroDirectivesOffsetMap.lookup(Name);
5546 }
5547 
5548 void ASTRecordWriter::AddSelectorRef(const Selector SelRef) {
5549   Record->push_back(Writer->getSelectorRef(SelRef));
5550 }
5551 
5552 SelectorID ASTWriter::getSelectorRef(Selector Sel) {
5553   if (Sel.getAsOpaquePtr() == nullptr) {
5554     return 0;
5555   }
5556 
5557   SelectorID SID = SelectorIDs[Sel];
5558   if (SID == 0 && Chain) {
5559     // This might trigger a ReadSelector callback, which will set the ID for
5560     // this selector.
5561     Chain->LoadSelector(Sel);
5562     SID = SelectorIDs[Sel];
5563   }
5564   if (SID == 0) {
5565     SID = NextSelectorID++;
5566     SelectorIDs[Sel] = SID;
5567   }
5568   return SID;
5569 }
5570 
5571 void ASTRecordWriter::AddCXXTemporary(const CXXTemporary *Temp) {
5572   AddDeclRef(Temp->getDestructor());
5573 }
5574 
5575 void ASTRecordWriter::AddTemplateArgumentLocInfo(
5576     TemplateArgument::ArgKind Kind, const TemplateArgumentLocInfo &Arg) {
5577   switch (Kind) {
5578   case TemplateArgument::Expression:
5579     AddStmt(Arg.getAsExpr());
5580     break;
5581   case TemplateArgument::Type:
5582     AddTypeSourceInfo(Arg.getAsTypeSourceInfo());
5583     break;
5584   case TemplateArgument::Template:
5585     AddNestedNameSpecifierLoc(Arg.getTemplateQualifierLoc());
5586     AddSourceLocation(Arg.getTemplateNameLoc());
5587     break;
5588   case TemplateArgument::TemplateExpansion:
5589     AddNestedNameSpecifierLoc(Arg.getTemplateQualifierLoc());
5590     AddSourceLocation(Arg.getTemplateNameLoc());
5591     AddSourceLocation(Arg.getTemplateEllipsisLoc());
5592     break;
5593   case TemplateArgument::Null:
5594   case TemplateArgument::Integral:
5595   case TemplateArgument::Declaration:
5596   case TemplateArgument::NullPtr:
5597   case TemplateArgument::Pack:
5598     // FIXME: Is this right?
5599     break;
5600   }
5601 }
5602 
5603 void ASTRecordWriter::AddTemplateArgumentLoc(const TemplateArgumentLoc &Arg) {
5604   AddTemplateArgument(Arg.getArgument());
5605 
5606   if (Arg.getArgument().getKind() == TemplateArgument::Expression) {
5607     bool InfoHasSameExpr
5608       = Arg.getArgument().getAsExpr() == Arg.getLocInfo().getAsExpr();
5609     Record->push_back(InfoHasSameExpr);
5610     if (InfoHasSameExpr)
5611       return; // Avoid storing the same expr twice.
5612   }
5613   AddTemplateArgumentLocInfo(Arg.getArgument().getKind(), Arg.getLocInfo());
5614 }
5615 
5616 void ASTRecordWriter::AddTypeSourceInfo(TypeSourceInfo *TInfo) {
5617   if (!TInfo) {
5618     AddTypeRef(QualType());
5619     return;
5620   }
5621 
5622   AddTypeRef(TInfo->getType());
5623   AddTypeLoc(TInfo->getTypeLoc());
5624 }
5625 
5626 void ASTRecordWriter::AddTypeLoc(TypeLoc TL) {
5627   TypeLocWriter TLW(*this);
5628   for (; !TL.isNull(); TL = TL.getNextTypeLoc())
5629     TLW.Visit(TL);
5630 }
5631 
5632 void ASTWriter::AddTypeRef(QualType T, RecordDataImpl &Record) {
5633   Record.push_back(GetOrCreateTypeID(T));
5634 }
5635 
5636 TypeID ASTWriter::GetOrCreateTypeID(QualType T) {
5637   assert(Context);
5638   return MakeTypeID(*Context, T, [&](QualType T) -> TypeIdx {
5639     if (T.isNull())
5640       return TypeIdx();
5641     assert(!T.getLocalFastQualifiers());
5642 
5643     TypeIdx &Idx = TypeIdxs[T];
5644     if (Idx.getIndex() == 0) {
5645       if (DoneWritingDeclsAndTypes) {
5646         assert(0 && "New type seen after serializing all the types to emit!");
5647         return TypeIdx();
5648       }
5649 
5650       // We haven't seen this type before. Assign it a new ID and put it
5651       // into the queue of types to emit.
5652       Idx = TypeIdx(NextTypeID++);
5653       DeclTypesToEmit.push(T);
5654     }
5655     return Idx;
5656   });
5657 }
5658 
5659 TypeID ASTWriter::getTypeID(QualType T) const {
5660   assert(Context);
5661   return MakeTypeID(*Context, T, [&](QualType T) -> TypeIdx {
5662     if (T.isNull())
5663       return TypeIdx();
5664     assert(!T.getLocalFastQualifiers());
5665 
5666     TypeIdxMap::const_iterator I = TypeIdxs.find(T);
5667     assert(I != TypeIdxs.end() && "Type not emitted!");
5668     return I->second;
5669   });
5670 }
5671 
5672 void ASTWriter::AddDeclRef(const Decl *D, RecordDataImpl &Record) {
5673   Record.push_back(GetDeclRef(D));
5674 }
5675 
5676 DeclID ASTWriter::GetDeclRef(const Decl *D) {
5677   assert(WritingAST && "Cannot request a declaration ID before AST writing");
5678 
5679   if (!D) {
5680     return 0;
5681   }
5682 
5683   // If D comes from an AST file, its declaration ID is already known and
5684   // fixed.
5685   if (D->isFromASTFile())
5686     return D->getGlobalID();
5687 
5688   assert(!(reinterpret_cast<uintptr_t>(D) & 0x01) && "Invalid decl pointer");
5689   DeclID &ID = DeclIDs[D];
5690   if (ID == 0) {
5691     if (DoneWritingDeclsAndTypes) {
5692       assert(0 && "New decl seen after serializing all the decls to emit!");
5693       return 0;
5694     }
5695 
5696     // We haven't seen this declaration before. Give it a new ID and
5697     // enqueue it in the list of declarations to emit.
5698     ID = NextDeclID++;
5699     DeclTypesToEmit.push(const_cast<Decl *>(D));
5700   }
5701 
5702   return ID;
5703 }
5704 
5705 DeclID ASTWriter::getDeclID(const Decl *D) {
5706   if (!D)
5707     return 0;
5708 
5709   // If D comes from an AST file, its declaration ID is already known and
5710   // fixed.
5711   if (D->isFromASTFile())
5712     return D->getGlobalID();
5713 
5714   assert(DeclIDs.find(D) != DeclIDs.end() && "Declaration not emitted!");
5715   return DeclIDs[D];
5716 }
5717 
5718 void ASTWriter::associateDeclWithFile(const Decl *D, DeclID ID) {
5719   assert(ID);
5720   assert(D);
5721 
5722   SourceLocation Loc = D->getLocation();
5723   if (Loc.isInvalid())
5724     return;
5725 
5726   // We only keep track of the file-level declarations of each file.
5727   if (!D->getLexicalDeclContext()->isFileContext())
5728     return;
5729   // FIXME: ParmVarDecls that are part of a function type of a parameter of
5730   // a function/objc method, should not have TU as lexical context.
5731   // TemplateTemplateParmDecls that are part of an alias template, should not
5732   // have TU as lexical context.
5733   if (isa<ParmVarDecl>(D) || isa<TemplateTemplateParmDecl>(D))
5734     return;
5735 
5736   SourceManager &SM = Context->getSourceManager();
5737   SourceLocation FileLoc = SM.getFileLoc(Loc);
5738   assert(SM.isLocalSourceLocation(FileLoc));
5739   FileID FID;
5740   unsigned Offset;
5741   std::tie(FID, Offset) = SM.getDecomposedLoc(FileLoc);
5742   if (FID.isInvalid())
5743     return;
5744   assert(SM.getSLocEntry(FID).isFile());
5745 
5746   DeclIDInFileInfo *&Info = FileDeclIDs[FID];
5747   if (!Info)
5748     Info = new DeclIDInFileInfo();
5749 
5750   std::pair<unsigned, serialization::DeclID> LocDecl(Offset, ID);
5751   LocDeclIDsTy &Decls = Info->DeclIDs;
5752 
5753   if (Decls.empty() || Decls.back().first <= Offset) {
5754     Decls.push_back(LocDecl);
5755     return;
5756   }
5757 
5758   LocDeclIDsTy::iterator I =
5759       llvm::upper_bound(Decls, LocDecl, llvm::less_first());
5760 
5761   Decls.insert(I, LocDecl);
5762 }
5763 
5764 void ASTRecordWriter::AddDeclarationName(DeclarationName Name) {
5765   // FIXME: Emit a stable enum for NameKind.  0 = Identifier etc.
5766   Record->push_back(Name.getNameKind());
5767   switch (Name.getNameKind()) {
5768   case DeclarationName::Identifier:
5769     AddIdentifierRef(Name.getAsIdentifierInfo());
5770     break;
5771 
5772   case DeclarationName::ObjCZeroArgSelector:
5773   case DeclarationName::ObjCOneArgSelector:
5774   case DeclarationName::ObjCMultiArgSelector:
5775     AddSelectorRef(Name.getObjCSelector());
5776     break;
5777 
5778   case DeclarationName::CXXConstructorName:
5779   case DeclarationName::CXXDestructorName:
5780   case DeclarationName::CXXConversionFunctionName:
5781     AddTypeRef(Name.getCXXNameType());
5782     break;
5783 
5784   case DeclarationName::CXXDeductionGuideName:
5785     AddDeclRef(Name.getCXXDeductionGuideTemplate());
5786     break;
5787 
5788   case DeclarationName::CXXOperatorName:
5789     Record->push_back(Name.getCXXOverloadedOperator());
5790     break;
5791 
5792   case DeclarationName::CXXLiteralOperatorName:
5793     AddIdentifierRef(Name.getCXXLiteralIdentifier());
5794     break;
5795 
5796   case DeclarationName::CXXUsingDirective:
5797     // No extra data to emit
5798     break;
5799   }
5800 }
5801 
5802 unsigned ASTWriter::getAnonymousDeclarationNumber(const NamedDecl *D) {
5803   assert(needsAnonymousDeclarationNumber(D) &&
5804          "expected an anonymous declaration");
5805 
5806   // Number the anonymous declarations within this context, if we've not
5807   // already done so.
5808   auto It = AnonymousDeclarationNumbers.find(D);
5809   if (It == AnonymousDeclarationNumbers.end()) {
5810     auto *DC = D->getLexicalDeclContext();
5811     numberAnonymousDeclsWithin(DC, [&](const NamedDecl *ND, unsigned Number) {
5812       AnonymousDeclarationNumbers[ND] = Number;
5813     });
5814 
5815     It = AnonymousDeclarationNumbers.find(D);
5816     assert(It != AnonymousDeclarationNumbers.end() &&
5817            "declaration not found within its lexical context");
5818   }
5819 
5820   return It->second;
5821 }
5822 
5823 void ASTRecordWriter::AddDeclarationNameLoc(const DeclarationNameLoc &DNLoc,
5824                                             DeclarationName Name) {
5825   switch (Name.getNameKind()) {
5826   case DeclarationName::CXXConstructorName:
5827   case DeclarationName::CXXDestructorName:
5828   case DeclarationName::CXXConversionFunctionName:
5829     AddTypeSourceInfo(DNLoc.NamedType.TInfo);
5830     break;
5831 
5832   case DeclarationName::CXXOperatorName:
5833     AddSourceLocation(SourceLocation::getFromRawEncoding(
5834         DNLoc.CXXOperatorName.BeginOpNameLoc));
5835     AddSourceLocation(
5836         SourceLocation::getFromRawEncoding(DNLoc.CXXOperatorName.EndOpNameLoc));
5837     break;
5838 
5839   case DeclarationName::CXXLiteralOperatorName:
5840     AddSourceLocation(SourceLocation::getFromRawEncoding(
5841         DNLoc.CXXLiteralOperatorName.OpNameLoc));
5842     break;
5843 
5844   case DeclarationName::Identifier:
5845   case DeclarationName::ObjCZeroArgSelector:
5846   case DeclarationName::ObjCOneArgSelector:
5847   case DeclarationName::ObjCMultiArgSelector:
5848   case DeclarationName::CXXUsingDirective:
5849   case DeclarationName::CXXDeductionGuideName:
5850     break;
5851   }
5852 }
5853 
5854 void ASTRecordWriter::AddDeclarationNameInfo(
5855     const DeclarationNameInfo &NameInfo) {
5856   AddDeclarationName(NameInfo.getName());
5857   AddSourceLocation(NameInfo.getLoc());
5858   AddDeclarationNameLoc(NameInfo.getInfo(), NameInfo.getName());
5859 }
5860 
5861 void ASTRecordWriter::AddQualifierInfo(const QualifierInfo &Info) {
5862   AddNestedNameSpecifierLoc(Info.QualifierLoc);
5863   Record->push_back(Info.NumTemplParamLists);
5864   for (unsigned i = 0, e = Info.NumTemplParamLists; i != e; ++i)
5865     AddTemplateParameterList(Info.TemplParamLists[i]);
5866 }
5867 
5868 void ASTRecordWriter::AddNestedNameSpecifier(NestedNameSpecifier *NNS) {
5869   // Nested name specifiers usually aren't too long. I think that 8 would
5870   // typically accommodate the vast majority.
5871   SmallVector<NestedNameSpecifier *, 8> NestedNames;
5872 
5873   // Push each of the NNS's onto a stack for serialization in reverse order.
5874   while (NNS) {
5875     NestedNames.push_back(NNS);
5876     NNS = NNS->getPrefix();
5877   }
5878 
5879   Record->push_back(NestedNames.size());
5880   while(!NestedNames.empty()) {
5881     NNS = NestedNames.pop_back_val();
5882     NestedNameSpecifier::SpecifierKind Kind = NNS->getKind();
5883     Record->push_back(Kind);
5884     switch (Kind) {
5885     case NestedNameSpecifier::Identifier:
5886       AddIdentifierRef(NNS->getAsIdentifier());
5887       break;
5888 
5889     case NestedNameSpecifier::Namespace:
5890       AddDeclRef(NNS->getAsNamespace());
5891       break;
5892 
5893     case NestedNameSpecifier::NamespaceAlias:
5894       AddDeclRef(NNS->getAsNamespaceAlias());
5895       break;
5896 
5897     case NestedNameSpecifier::TypeSpec:
5898     case NestedNameSpecifier::TypeSpecWithTemplate:
5899       AddTypeRef(QualType(NNS->getAsType(), 0));
5900       Record->push_back(Kind == NestedNameSpecifier::TypeSpecWithTemplate);
5901       break;
5902 
5903     case NestedNameSpecifier::Global:
5904       // Don't need to write an associated value.
5905       break;
5906 
5907     case NestedNameSpecifier::Super:
5908       AddDeclRef(NNS->getAsRecordDecl());
5909       break;
5910     }
5911   }
5912 }
5913 
5914 void ASTRecordWriter::AddNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS) {
5915   // Nested name specifiers usually aren't too long. I think that 8 would
5916   // typically accommodate the vast majority.
5917   SmallVector<NestedNameSpecifierLoc , 8> NestedNames;
5918 
5919   // Push each of the nested-name-specifiers's onto a stack for
5920   // serialization in reverse order.
5921   while (NNS) {
5922     NestedNames.push_back(NNS);
5923     NNS = NNS.getPrefix();
5924   }
5925 
5926   Record->push_back(NestedNames.size());
5927   while(!NestedNames.empty()) {
5928     NNS = NestedNames.pop_back_val();
5929     NestedNameSpecifier::SpecifierKind Kind
5930       = NNS.getNestedNameSpecifier()->getKind();
5931     Record->push_back(Kind);
5932     switch (Kind) {
5933     case NestedNameSpecifier::Identifier:
5934       AddIdentifierRef(NNS.getNestedNameSpecifier()->getAsIdentifier());
5935       AddSourceRange(NNS.getLocalSourceRange());
5936       break;
5937 
5938     case NestedNameSpecifier::Namespace:
5939       AddDeclRef(NNS.getNestedNameSpecifier()->getAsNamespace());
5940       AddSourceRange(NNS.getLocalSourceRange());
5941       break;
5942 
5943     case NestedNameSpecifier::NamespaceAlias:
5944       AddDeclRef(NNS.getNestedNameSpecifier()->getAsNamespaceAlias());
5945       AddSourceRange(NNS.getLocalSourceRange());
5946       break;
5947 
5948     case NestedNameSpecifier::TypeSpec:
5949     case NestedNameSpecifier::TypeSpecWithTemplate:
5950       Record->push_back(Kind == NestedNameSpecifier::TypeSpecWithTemplate);
5951       AddTypeRef(NNS.getTypeLoc().getType());
5952       AddTypeLoc(NNS.getTypeLoc());
5953       AddSourceLocation(NNS.getLocalSourceRange().getEnd());
5954       break;
5955 
5956     case NestedNameSpecifier::Global:
5957       AddSourceLocation(NNS.getLocalSourceRange().getEnd());
5958       break;
5959 
5960     case NestedNameSpecifier::Super:
5961       AddDeclRef(NNS.getNestedNameSpecifier()->getAsRecordDecl());
5962       AddSourceRange(NNS.getLocalSourceRange());
5963       break;
5964     }
5965   }
5966 }
5967 
5968 void ASTRecordWriter::AddTemplateName(TemplateName Name) {
5969   TemplateName::NameKind Kind = Name.getKind();
5970   Record->push_back(Kind);
5971   switch (Kind) {
5972   case TemplateName::Template:
5973     AddDeclRef(Name.getAsTemplateDecl());
5974     break;
5975 
5976   case TemplateName::OverloadedTemplate: {
5977     OverloadedTemplateStorage *OvT = Name.getAsOverloadedTemplate();
5978     Record->push_back(OvT->size());
5979     for (const auto &I : *OvT)
5980       AddDeclRef(I);
5981     break;
5982   }
5983 
5984   case TemplateName::AssumedTemplate: {
5985     AssumedTemplateStorage *ADLT = Name.getAsAssumedTemplateName();
5986     AddDeclarationName(ADLT->getDeclName());
5987     break;
5988   }
5989 
5990   case TemplateName::QualifiedTemplate: {
5991     QualifiedTemplateName *QualT = Name.getAsQualifiedTemplateName();
5992     AddNestedNameSpecifier(QualT->getQualifier());
5993     Record->push_back(QualT->hasTemplateKeyword());
5994     AddDeclRef(QualT->getTemplateDecl());
5995     break;
5996   }
5997 
5998   case TemplateName::DependentTemplate: {
5999     DependentTemplateName *DepT = Name.getAsDependentTemplateName();
6000     AddNestedNameSpecifier(DepT->getQualifier());
6001     Record->push_back(DepT->isIdentifier());
6002     if (DepT->isIdentifier())
6003       AddIdentifierRef(DepT->getIdentifier());
6004     else
6005       Record->push_back(DepT->getOperator());
6006     break;
6007   }
6008 
6009   case TemplateName::SubstTemplateTemplateParm: {
6010     SubstTemplateTemplateParmStorage *subst
6011       = Name.getAsSubstTemplateTemplateParm();
6012     AddDeclRef(subst->getParameter());
6013     AddTemplateName(subst->getReplacement());
6014     break;
6015   }
6016 
6017   case TemplateName::SubstTemplateTemplateParmPack: {
6018     SubstTemplateTemplateParmPackStorage *SubstPack
6019       = Name.getAsSubstTemplateTemplateParmPack();
6020     AddDeclRef(SubstPack->getParameterPack());
6021     AddTemplateArgument(SubstPack->getArgumentPack());
6022     break;
6023   }
6024   }
6025 }
6026 
6027 void ASTRecordWriter::AddTemplateArgument(const TemplateArgument &Arg) {
6028   Record->push_back(Arg.getKind());
6029   switch (Arg.getKind()) {
6030   case TemplateArgument::Null:
6031     break;
6032   case TemplateArgument::Type:
6033     AddTypeRef(Arg.getAsType());
6034     break;
6035   case TemplateArgument::Declaration:
6036     AddDeclRef(Arg.getAsDecl());
6037     AddTypeRef(Arg.getParamTypeForDecl());
6038     break;
6039   case TemplateArgument::NullPtr:
6040     AddTypeRef(Arg.getNullPtrType());
6041     break;
6042   case TemplateArgument::Integral:
6043     AddAPSInt(Arg.getAsIntegral());
6044     AddTypeRef(Arg.getIntegralType());
6045     break;
6046   case TemplateArgument::Template:
6047     AddTemplateName(Arg.getAsTemplateOrTemplatePattern());
6048     break;
6049   case TemplateArgument::TemplateExpansion:
6050     AddTemplateName(Arg.getAsTemplateOrTemplatePattern());
6051     if (Optional<unsigned> NumExpansions = Arg.getNumTemplateExpansions())
6052       Record->push_back(*NumExpansions + 1);
6053     else
6054       Record->push_back(0);
6055     break;
6056   case TemplateArgument::Expression:
6057     AddStmt(Arg.getAsExpr());
6058     break;
6059   case TemplateArgument::Pack:
6060     Record->push_back(Arg.pack_size());
6061     for (const auto &P : Arg.pack_elements())
6062       AddTemplateArgument(P);
6063     break;
6064   }
6065 }
6066 
6067 void ASTRecordWriter::AddTemplateParameterList(
6068     const TemplateParameterList *TemplateParams) {
6069   assert(TemplateParams && "No TemplateParams!");
6070   AddSourceLocation(TemplateParams->getTemplateLoc());
6071   AddSourceLocation(TemplateParams->getLAngleLoc());
6072   AddSourceLocation(TemplateParams->getRAngleLoc());
6073 
6074   Record->push_back(TemplateParams->size());
6075   for (const auto &P : *TemplateParams)
6076     AddDeclRef(P);
6077   if (const Expr *RequiresClause = TemplateParams->getRequiresClause()) {
6078     Record->push_back(true);
6079     AddStmt(const_cast<Expr*>(RequiresClause));
6080   } else {
6081     Record->push_back(false);
6082   }
6083 }
6084 
6085 /// Emit a template argument list.
6086 void ASTRecordWriter::AddTemplateArgumentList(
6087     const TemplateArgumentList *TemplateArgs) {
6088   assert(TemplateArgs && "No TemplateArgs!");
6089   Record->push_back(TemplateArgs->size());
6090   for (int i = 0, e = TemplateArgs->size(); i != e; ++i)
6091     AddTemplateArgument(TemplateArgs->get(i));
6092 }
6093 
6094 void ASTRecordWriter::AddASTTemplateArgumentListInfo(
6095     const ASTTemplateArgumentListInfo *ASTTemplArgList) {
6096   assert(ASTTemplArgList && "No ASTTemplArgList!");
6097   AddSourceLocation(ASTTemplArgList->LAngleLoc);
6098   AddSourceLocation(ASTTemplArgList->RAngleLoc);
6099   Record->push_back(ASTTemplArgList->NumTemplateArgs);
6100   const TemplateArgumentLoc *TemplArgs = ASTTemplArgList->getTemplateArgs();
6101   for (int i = 0, e = ASTTemplArgList->NumTemplateArgs; i != e; ++i)
6102     AddTemplateArgumentLoc(TemplArgs[i]);
6103 }
6104 
6105 void ASTRecordWriter::AddUnresolvedSet(const ASTUnresolvedSet &Set) {
6106   Record->push_back(Set.size());
6107   for (ASTUnresolvedSet::const_iterator
6108          I = Set.begin(), E = Set.end(); I != E; ++I) {
6109     AddDeclRef(I.getDecl());
6110     Record->push_back(I.getAccess());
6111   }
6112 }
6113 
6114 // FIXME: Move this out of the main ASTRecordWriter interface.
6115 void ASTRecordWriter::AddCXXBaseSpecifier(const CXXBaseSpecifier &Base) {
6116   Record->push_back(Base.isVirtual());
6117   Record->push_back(Base.isBaseOfClass());
6118   Record->push_back(Base.getAccessSpecifierAsWritten());
6119   Record->push_back(Base.getInheritConstructors());
6120   AddTypeSourceInfo(Base.getTypeSourceInfo());
6121   AddSourceRange(Base.getSourceRange());
6122   AddSourceLocation(Base.isPackExpansion()? Base.getEllipsisLoc()
6123                                           : SourceLocation());
6124 }
6125 
6126 static uint64_t EmitCXXBaseSpecifiers(ASTWriter &W,
6127                                       ArrayRef<CXXBaseSpecifier> Bases) {
6128   ASTWriter::RecordData Record;
6129   ASTRecordWriter Writer(W, Record);
6130   Writer.push_back(Bases.size());
6131 
6132   for (auto &Base : Bases)
6133     Writer.AddCXXBaseSpecifier(Base);
6134 
6135   return Writer.Emit(serialization::DECL_CXX_BASE_SPECIFIERS);
6136 }
6137 
6138 // FIXME: Move this out of the main ASTRecordWriter interface.
6139 void ASTRecordWriter::AddCXXBaseSpecifiers(ArrayRef<CXXBaseSpecifier> Bases) {
6140   AddOffset(EmitCXXBaseSpecifiers(*Writer, Bases));
6141 }
6142 
6143 static uint64_t
6144 EmitCXXCtorInitializers(ASTWriter &W,
6145                         ArrayRef<CXXCtorInitializer *> CtorInits) {
6146   ASTWriter::RecordData Record;
6147   ASTRecordWriter Writer(W, Record);
6148   Writer.push_back(CtorInits.size());
6149 
6150   for (auto *Init : CtorInits) {
6151     if (Init->isBaseInitializer()) {
6152       Writer.push_back(CTOR_INITIALIZER_BASE);
6153       Writer.AddTypeSourceInfo(Init->getTypeSourceInfo());
6154       Writer.push_back(Init->isBaseVirtual());
6155     } else if (Init->isDelegatingInitializer()) {
6156       Writer.push_back(CTOR_INITIALIZER_DELEGATING);
6157       Writer.AddTypeSourceInfo(Init->getTypeSourceInfo());
6158     } else if (Init->isMemberInitializer()){
6159       Writer.push_back(CTOR_INITIALIZER_MEMBER);
6160       Writer.AddDeclRef(Init->getMember());
6161     } else {
6162       Writer.push_back(CTOR_INITIALIZER_INDIRECT_MEMBER);
6163       Writer.AddDeclRef(Init->getIndirectMember());
6164     }
6165 
6166     Writer.AddSourceLocation(Init->getMemberLocation());
6167     Writer.AddStmt(Init->getInit());
6168     Writer.AddSourceLocation(Init->getLParenLoc());
6169     Writer.AddSourceLocation(Init->getRParenLoc());
6170     Writer.push_back(Init->isWritten());
6171     if (Init->isWritten())
6172       Writer.push_back(Init->getSourceOrder());
6173   }
6174 
6175   return Writer.Emit(serialization::DECL_CXX_CTOR_INITIALIZERS);
6176 }
6177 
6178 // FIXME: Move this out of the main ASTRecordWriter interface.
6179 void ASTRecordWriter::AddCXXCtorInitializers(
6180     ArrayRef<CXXCtorInitializer *> CtorInits) {
6181   AddOffset(EmitCXXCtorInitializers(*Writer, CtorInits));
6182 }
6183 
6184 void ASTRecordWriter::AddCXXDefinitionData(const CXXRecordDecl *D) {
6185   auto &Data = D->data();
6186   Record->push_back(Data.IsLambda);
6187 
6188   #define FIELD(Name, Width, Merge) \
6189   Record->push_back(Data.Name);
6190   #include "clang/AST/CXXRecordDeclDefinitionBits.def"
6191 
6192   // getODRHash will compute the ODRHash if it has not been previously computed.
6193   Record->push_back(D->getODRHash());
6194   bool ModulesDebugInfo = Writer->Context->getLangOpts().ModulesDebugInfo &&
6195                           Writer->WritingModule && !D->isDependentType();
6196   Record->push_back(ModulesDebugInfo);
6197   if (ModulesDebugInfo)
6198     Writer->ModularCodegenDecls.push_back(Writer->GetDeclRef(D));
6199 
6200   // IsLambda bit is already saved.
6201 
6202   Record->push_back(Data.NumBases);
6203   if (Data.NumBases > 0)
6204     AddCXXBaseSpecifiers(Data.bases());
6205 
6206   // FIXME: Make VBases lazily computed when needed to avoid storing them.
6207   Record->push_back(Data.NumVBases);
6208   if (Data.NumVBases > 0)
6209     AddCXXBaseSpecifiers(Data.vbases());
6210 
6211   AddUnresolvedSet(Data.Conversions.get(*Writer->Context));
6212   Record->push_back(Data.ComputedVisibleConversions);
6213   if (Data.ComputedVisibleConversions)
6214     AddUnresolvedSet(Data.VisibleConversions.get(*Writer->Context));
6215   // Data.Definition is the owning decl, no need to write it.
6216   AddDeclRef(D->getFirstFriend());
6217 
6218   // Add lambda-specific data.
6219   if (Data.IsLambda) {
6220     auto &Lambda = D->getLambdaData();
6221     Record->push_back(Lambda.Dependent);
6222     Record->push_back(Lambda.IsGenericLambda);
6223     Record->push_back(Lambda.CaptureDefault);
6224     Record->push_back(Lambda.NumCaptures);
6225     Record->push_back(Lambda.NumExplicitCaptures);
6226     Record->push_back(Lambda.ManglingNumber);
6227     AddDeclRef(D->getLambdaContextDecl());
6228     AddTypeSourceInfo(Lambda.MethodTyInfo);
6229     for (unsigned I = 0, N = Lambda.NumCaptures; I != N; ++I) {
6230       const LambdaCapture &Capture = Lambda.Captures[I];
6231       AddSourceLocation(Capture.getLocation());
6232       Record->push_back(Capture.isImplicit());
6233       Record->push_back(Capture.getCaptureKind());
6234       switch (Capture.getCaptureKind()) {
6235       case LCK_StarThis:
6236       case LCK_This:
6237       case LCK_VLAType:
6238         break;
6239       case LCK_ByCopy:
6240       case LCK_ByRef:
6241         VarDecl *Var =
6242             Capture.capturesVariable() ? Capture.getCapturedVar() : nullptr;
6243         AddDeclRef(Var);
6244         AddSourceLocation(Capture.isPackExpansion() ? Capture.getEllipsisLoc()
6245                                                     : SourceLocation());
6246         break;
6247       }
6248     }
6249   }
6250 }
6251 
6252 void ASTWriter::ReaderInitialized(ASTReader *Reader) {
6253   assert(Reader && "Cannot remove chain");
6254   assert((!Chain || Chain == Reader) && "Cannot replace chain");
6255   assert(FirstDeclID == NextDeclID &&
6256          FirstTypeID == NextTypeID &&
6257          FirstIdentID == NextIdentID &&
6258          FirstMacroID == NextMacroID &&
6259          FirstSubmoduleID == NextSubmoduleID &&
6260          FirstSelectorID == NextSelectorID &&
6261          "Setting chain after writing has started.");
6262 
6263   Chain = Reader;
6264 
6265   // Note, this will get called multiple times, once one the reader starts up
6266   // and again each time it's done reading a PCH or module.
6267   FirstDeclID = NUM_PREDEF_DECL_IDS + Chain->getTotalNumDecls();
6268   FirstTypeID = NUM_PREDEF_TYPE_IDS + Chain->getTotalNumTypes();
6269   FirstIdentID = NUM_PREDEF_IDENT_IDS + Chain->getTotalNumIdentifiers();
6270   FirstMacroID = NUM_PREDEF_MACRO_IDS + Chain->getTotalNumMacros();
6271   FirstSubmoduleID = NUM_PREDEF_SUBMODULE_IDS + Chain->getTotalNumSubmodules();
6272   FirstSelectorID = NUM_PREDEF_SELECTOR_IDS + Chain->getTotalNumSelectors();
6273   NextDeclID = FirstDeclID;
6274   NextTypeID = FirstTypeID;
6275   NextIdentID = FirstIdentID;
6276   NextMacroID = FirstMacroID;
6277   NextSelectorID = FirstSelectorID;
6278   NextSubmoduleID = FirstSubmoduleID;
6279 }
6280 
6281 void ASTWriter::IdentifierRead(IdentID ID, IdentifierInfo *II) {
6282   // Always keep the highest ID. See \p TypeRead() for more information.
6283   IdentID &StoredID = IdentifierIDs[II];
6284   if (ID > StoredID)
6285     StoredID = ID;
6286 }
6287 
6288 void ASTWriter::MacroRead(serialization::MacroID ID, MacroInfo *MI) {
6289   // Always keep the highest ID. See \p TypeRead() for more information.
6290   MacroID &StoredID = MacroIDs[MI];
6291   if (ID > StoredID)
6292     StoredID = ID;
6293 }
6294 
6295 void ASTWriter::TypeRead(TypeIdx Idx, QualType T) {
6296   // Always take the highest-numbered type index. This copes with an interesting
6297   // case for chained AST writing where we schedule writing the type and then,
6298   // later, deserialize the type from another AST. In this case, we want to
6299   // keep the higher-numbered entry so that we can properly write it out to
6300   // the AST file.
6301   TypeIdx &StoredIdx = TypeIdxs[T];
6302   if (Idx.getIndex() >= StoredIdx.getIndex())
6303     StoredIdx = Idx;
6304 }
6305 
6306 void ASTWriter::SelectorRead(SelectorID ID, Selector S) {
6307   // Always keep the highest ID. See \p TypeRead() for more information.
6308   SelectorID &StoredID = SelectorIDs[S];
6309   if (ID > StoredID)
6310     StoredID = ID;
6311 }
6312 
6313 void ASTWriter::MacroDefinitionRead(serialization::PreprocessedEntityID ID,
6314                                     MacroDefinitionRecord *MD) {
6315   assert(MacroDefinitions.find(MD) == MacroDefinitions.end());
6316   MacroDefinitions[MD] = ID;
6317 }
6318 
6319 void ASTWriter::ModuleRead(serialization::SubmoduleID ID, Module *Mod) {
6320   assert(SubmoduleIDs.find(Mod) == SubmoduleIDs.end());
6321   SubmoduleIDs[Mod] = ID;
6322 }
6323 
6324 void ASTWriter::CompletedTagDefinition(const TagDecl *D) {
6325   if (Chain && Chain->isProcessingUpdateRecords()) return;
6326   assert(D->isCompleteDefinition());
6327   assert(!WritingAST && "Already writing the AST!");
6328   if (auto *RD = dyn_cast<CXXRecordDecl>(D)) {
6329     // We are interested when a PCH decl is modified.
6330     if (RD->isFromASTFile()) {
6331       // A forward reference was mutated into a definition. Rewrite it.
6332       // FIXME: This happens during template instantiation, should we
6333       // have created a new definition decl instead ?
6334       assert(isTemplateInstantiation(RD->getTemplateSpecializationKind()) &&
6335              "completed a tag from another module but not by instantiation?");
6336       DeclUpdates[RD].push_back(
6337           DeclUpdate(UPD_CXX_INSTANTIATED_CLASS_DEFINITION));
6338     }
6339   }
6340 }
6341 
6342 static bool isImportedDeclContext(ASTReader *Chain, const Decl *D) {
6343   if (D->isFromASTFile())
6344     return true;
6345 
6346   // The predefined __va_list_tag struct is imported if we imported any decls.
6347   // FIXME: This is a gross hack.
6348   return D == D->getASTContext().getVaListTagDecl();
6349 }
6350 
6351 void ASTWriter::AddedVisibleDecl(const DeclContext *DC, const Decl *D) {
6352   if (Chain && Chain->isProcessingUpdateRecords()) return;
6353   assert(DC->isLookupContext() &&
6354           "Should not add lookup results to non-lookup contexts!");
6355 
6356   // TU is handled elsewhere.
6357   if (isa<TranslationUnitDecl>(DC))
6358     return;
6359 
6360   // Namespaces are handled elsewhere, except for template instantiations of
6361   // FunctionTemplateDecls in namespaces. We are interested in cases where the
6362   // local instantiations are added to an imported context. Only happens when
6363   // adding ADL lookup candidates, for example templated friends.
6364   if (isa<NamespaceDecl>(DC) && D->getFriendObjectKind() == Decl::FOK_None &&
6365       !isa<FunctionTemplateDecl>(D))
6366     return;
6367 
6368   // We're only interested in cases where a local declaration is added to an
6369   // imported context.
6370   if (D->isFromASTFile() || !isImportedDeclContext(Chain, cast<Decl>(DC)))
6371     return;
6372 
6373   assert(DC == DC->getPrimaryContext() && "added to non-primary context");
6374   assert(!getDefinitiveDeclContext(DC) && "DeclContext not definitive!");
6375   assert(!WritingAST && "Already writing the AST!");
6376   if (UpdatedDeclContexts.insert(DC) && !cast<Decl>(DC)->isFromASTFile()) {
6377     // We're adding a visible declaration to a predefined decl context. Ensure
6378     // that we write out all of its lookup results so we don't get a nasty
6379     // surprise when we try to emit its lookup table.
6380     for (auto *Child : DC->decls())
6381       DeclsToEmitEvenIfUnreferenced.push_back(Child);
6382   }
6383   DeclsToEmitEvenIfUnreferenced.push_back(D);
6384 }
6385 
6386 void ASTWriter::AddedCXXImplicitMember(const CXXRecordDecl *RD, const Decl *D) {
6387   if (Chain && Chain->isProcessingUpdateRecords()) return;
6388   assert(D->isImplicit());
6389 
6390   // We're only interested in cases where a local declaration is added to an
6391   // imported context.
6392   if (D->isFromASTFile() || !isImportedDeclContext(Chain, RD))
6393     return;
6394 
6395   if (!isa<CXXMethodDecl>(D))
6396     return;
6397 
6398   // A decl coming from PCH was modified.
6399   assert(RD->isCompleteDefinition());
6400   assert(!WritingAST && "Already writing the AST!");
6401   DeclUpdates[RD].push_back(DeclUpdate(UPD_CXX_ADDED_IMPLICIT_MEMBER, D));
6402 }
6403 
6404 void ASTWriter::ResolvedExceptionSpec(const FunctionDecl *FD) {
6405   if (Chain && Chain->isProcessingUpdateRecords()) return;
6406   assert(!DoneWritingDeclsAndTypes && "Already done writing updates!");
6407   if (!Chain) return;
6408   Chain->forEachImportedKeyDecl(FD, [&](const Decl *D) {
6409     // If we don't already know the exception specification for this redecl
6410     // chain, add an update record for it.
6411     if (isUnresolvedExceptionSpec(cast<FunctionDecl>(D)
6412                                       ->getType()
6413                                       ->castAs<FunctionProtoType>()
6414                                       ->getExceptionSpecType()))
6415       DeclUpdates[D].push_back(UPD_CXX_RESOLVED_EXCEPTION_SPEC);
6416   });
6417 }
6418 
6419 void ASTWriter::DeducedReturnType(const FunctionDecl *FD, QualType ReturnType) {
6420   if (Chain && Chain->isProcessingUpdateRecords()) return;
6421   assert(!WritingAST && "Already writing the AST!");
6422   if (!Chain) return;
6423   Chain->forEachImportedKeyDecl(FD, [&](const Decl *D) {
6424     DeclUpdates[D].push_back(
6425         DeclUpdate(UPD_CXX_DEDUCED_RETURN_TYPE, ReturnType));
6426   });
6427 }
6428 
6429 void ASTWriter::ResolvedOperatorDelete(const CXXDestructorDecl *DD,
6430                                        const FunctionDecl *Delete,
6431                                        Expr *ThisArg) {
6432   if (Chain && Chain->isProcessingUpdateRecords()) return;
6433   assert(!WritingAST && "Already writing the AST!");
6434   assert(Delete && "Not given an operator delete");
6435   if (!Chain) return;
6436   Chain->forEachImportedKeyDecl(DD, [&](const Decl *D) {
6437     DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_RESOLVED_DTOR_DELETE, Delete));
6438   });
6439 }
6440 
6441 void ASTWriter::CompletedImplicitDefinition(const FunctionDecl *D) {
6442   if (Chain && Chain->isProcessingUpdateRecords()) return;
6443   assert(!WritingAST && "Already writing the AST!");
6444   if (!D->isFromASTFile())
6445     return; // Declaration not imported from PCH.
6446 
6447   // Implicit function decl from a PCH was defined.
6448   DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_ADDED_FUNCTION_DEFINITION));
6449 }
6450 
6451 void ASTWriter::VariableDefinitionInstantiated(const VarDecl *D) {
6452   if (Chain && Chain->isProcessingUpdateRecords()) return;
6453   assert(!WritingAST && "Already writing the AST!");
6454   if (!D->isFromASTFile())
6455     return;
6456 
6457   DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_ADDED_VAR_DEFINITION));
6458 }
6459 
6460 void ASTWriter::FunctionDefinitionInstantiated(const FunctionDecl *D) {
6461   if (Chain && Chain->isProcessingUpdateRecords()) return;
6462   assert(!WritingAST && "Already writing the AST!");
6463   if (!D->isFromASTFile())
6464     return;
6465 
6466   DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_ADDED_FUNCTION_DEFINITION));
6467 }
6468 
6469 void ASTWriter::InstantiationRequested(const ValueDecl *D) {
6470   if (Chain && Chain->isProcessingUpdateRecords()) return;
6471   assert(!WritingAST && "Already writing the AST!");
6472   if (!D->isFromASTFile())
6473     return;
6474 
6475   // Since the actual instantiation is delayed, this really means that we need
6476   // to update the instantiation location.
6477   SourceLocation POI;
6478   if (auto *VD = dyn_cast<VarDecl>(D))
6479     POI = VD->getPointOfInstantiation();
6480   else
6481     POI = cast<FunctionDecl>(D)->getPointOfInstantiation();
6482   DeclUpdates[D].push_back(DeclUpdate(UPD_CXX_POINT_OF_INSTANTIATION, POI));
6483 }
6484 
6485 void ASTWriter::DefaultArgumentInstantiated(const ParmVarDecl *D) {
6486   if (Chain && Chain->isProcessingUpdateRecords()) return;
6487   assert(!WritingAST && "Already writing the AST!");
6488   if (!D->isFromASTFile())
6489     return;
6490 
6491   DeclUpdates[D].push_back(
6492       DeclUpdate(UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT, D));
6493 }
6494 
6495 void ASTWriter::DefaultMemberInitializerInstantiated(const FieldDecl *D) {
6496   assert(!WritingAST && "Already writing the AST!");
6497   if (!D->isFromASTFile())
6498     return;
6499 
6500   DeclUpdates[D].push_back(
6501       DeclUpdate(UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER, D));
6502 }
6503 
6504 void ASTWriter::AddedObjCCategoryToInterface(const ObjCCategoryDecl *CatD,
6505                                              const ObjCInterfaceDecl *IFD) {
6506   if (Chain && Chain->isProcessingUpdateRecords()) return;
6507   assert(!WritingAST && "Already writing the AST!");
6508   if (!IFD->isFromASTFile())
6509     return; // Declaration not imported from PCH.
6510 
6511   assert(IFD->getDefinition() && "Category on a class without a definition?");
6512   ObjCClassesWithCategories.insert(
6513     const_cast<ObjCInterfaceDecl *>(IFD->getDefinition()));
6514 }
6515 
6516 void ASTWriter::DeclarationMarkedUsed(const Decl *D) {
6517   if (Chain && Chain->isProcessingUpdateRecords()) return;
6518   assert(!WritingAST && "Already writing the AST!");
6519 
6520   // If there is *any* declaration of the entity that's not from an AST file,
6521   // we can skip writing the update record. We make sure that isUsed() triggers
6522   // completion of the redeclaration chain of the entity.
6523   for (auto Prev = D->getMostRecentDecl(); Prev; Prev = Prev->getPreviousDecl())
6524     if (IsLocalDecl(Prev))
6525       return;
6526 
6527   DeclUpdates[D].push_back(DeclUpdate(UPD_DECL_MARKED_USED));
6528 }
6529 
6530 void ASTWriter::DeclarationMarkedOpenMPThreadPrivate(const Decl *D) {
6531   if (Chain && Chain->isProcessingUpdateRecords()) return;
6532   assert(!WritingAST && "Already writing the AST!");
6533   if (!D->isFromASTFile())
6534     return;
6535 
6536   DeclUpdates[D].push_back(DeclUpdate(UPD_DECL_MARKED_OPENMP_THREADPRIVATE));
6537 }
6538 
6539 void ASTWriter::DeclarationMarkedOpenMPAllocate(const Decl *D, const Attr *A) {
6540   if (Chain && Chain->isProcessingUpdateRecords()) return;
6541   assert(!WritingAST && "Already writing the AST!");
6542   if (!D->isFromASTFile())
6543     return;
6544 
6545   DeclUpdates[D].push_back(DeclUpdate(UPD_DECL_MARKED_OPENMP_ALLOCATE, A));
6546 }
6547 
6548 void ASTWriter::DeclarationMarkedOpenMPDeclareTarget(const Decl *D,
6549                                                      const Attr *Attr) {
6550   if (Chain && Chain->isProcessingUpdateRecords()) return;
6551   assert(!WritingAST && "Already writing the AST!");
6552   if (!D->isFromASTFile())
6553     return;
6554 
6555   DeclUpdates[D].push_back(
6556       DeclUpdate(UPD_DECL_MARKED_OPENMP_DECLARETARGET, Attr));
6557 }
6558 
6559 void ASTWriter::RedefinedHiddenDefinition(const NamedDecl *D, Module *M) {
6560   if (Chain && Chain->isProcessingUpdateRecords()) return;
6561   assert(!WritingAST && "Already writing the AST!");
6562   assert(D->isHidden() && "expected a hidden declaration");
6563   DeclUpdates[D].push_back(DeclUpdate(UPD_DECL_EXPORTED, M));
6564 }
6565 
6566 void ASTWriter::AddedAttributeToRecord(const Attr *Attr,
6567                                        const RecordDecl *Record) {
6568   if (Chain && Chain->isProcessingUpdateRecords()) return;
6569   assert(!WritingAST && "Already writing the AST!");
6570   if (!Record->isFromASTFile())
6571     return;
6572   DeclUpdates[Record].push_back(DeclUpdate(UPD_ADDED_ATTR_TO_RECORD, Attr));
6573 }
6574 
6575 void ASTWriter::AddedCXXTemplateSpecialization(
6576     const ClassTemplateDecl *TD, const ClassTemplateSpecializationDecl *D) {
6577   assert(!WritingAST && "Already writing the AST!");
6578 
6579   if (!TD->getFirstDecl()->isFromASTFile())
6580     return;
6581   if (Chain && Chain->isProcessingUpdateRecords())
6582     return;
6583 
6584   DeclsToEmitEvenIfUnreferenced.push_back(D);
6585 }
6586 
6587 void ASTWriter::AddedCXXTemplateSpecialization(
6588     const VarTemplateDecl *TD, const VarTemplateSpecializationDecl *D) {
6589   assert(!WritingAST && "Already writing the AST!");
6590 
6591   if (!TD->getFirstDecl()->isFromASTFile())
6592     return;
6593   if (Chain && Chain->isProcessingUpdateRecords())
6594     return;
6595 
6596   DeclsToEmitEvenIfUnreferenced.push_back(D);
6597 }
6598 
6599 void ASTWriter::AddedCXXTemplateSpecialization(const FunctionTemplateDecl *TD,
6600                                                const FunctionDecl *D) {
6601   assert(!WritingAST && "Already writing the AST!");
6602 
6603   if (!TD->getFirstDecl()->isFromASTFile())
6604     return;
6605   if (Chain && Chain->isProcessingUpdateRecords())
6606     return;
6607 
6608   DeclsToEmitEvenIfUnreferenced.push_back(D);
6609 }
6610 
6611 //===----------------------------------------------------------------------===//
6612 //// OMPClause Serialization
6613 ////===----------------------------------------------------------------------===//
6614 
6615 void OMPClauseWriter::writeClause(OMPClause *C) {
6616   Record.push_back(C->getClauseKind());
6617   Visit(C);
6618   Record.AddSourceLocation(C->getBeginLoc());
6619   Record.AddSourceLocation(C->getEndLoc());
6620 }
6621 
6622 void OMPClauseWriter::VisitOMPClauseWithPreInit(OMPClauseWithPreInit *C) {
6623   Record.push_back(C->getCaptureRegion());
6624   Record.AddStmt(C->getPreInitStmt());
6625 }
6626 
6627 void OMPClauseWriter::VisitOMPClauseWithPostUpdate(OMPClauseWithPostUpdate *C) {
6628   VisitOMPClauseWithPreInit(C);
6629   Record.AddStmt(C->getPostUpdateExpr());
6630 }
6631 
6632 void OMPClauseWriter::VisitOMPIfClause(OMPIfClause *C) {
6633   VisitOMPClauseWithPreInit(C);
6634   Record.push_back(C->getNameModifier());
6635   Record.AddSourceLocation(C->getNameModifierLoc());
6636   Record.AddSourceLocation(C->getColonLoc());
6637   Record.AddStmt(C->getCondition());
6638   Record.AddSourceLocation(C->getLParenLoc());
6639 }
6640 
6641 void OMPClauseWriter::VisitOMPFinalClause(OMPFinalClause *C) {
6642   VisitOMPClauseWithPreInit(C);
6643   Record.AddStmt(C->getCondition());
6644   Record.AddSourceLocation(C->getLParenLoc());
6645 }
6646 
6647 void OMPClauseWriter::VisitOMPNumThreadsClause(OMPNumThreadsClause *C) {
6648   VisitOMPClauseWithPreInit(C);
6649   Record.AddStmt(C->getNumThreads());
6650   Record.AddSourceLocation(C->getLParenLoc());
6651 }
6652 
6653 void OMPClauseWriter::VisitOMPSafelenClause(OMPSafelenClause *C) {
6654   Record.AddStmt(C->getSafelen());
6655   Record.AddSourceLocation(C->getLParenLoc());
6656 }
6657 
6658 void OMPClauseWriter::VisitOMPSimdlenClause(OMPSimdlenClause *C) {
6659   Record.AddStmt(C->getSimdlen());
6660   Record.AddSourceLocation(C->getLParenLoc());
6661 }
6662 
6663 void OMPClauseWriter::VisitOMPAllocatorClause(OMPAllocatorClause *C) {
6664   Record.AddStmt(C->getAllocator());
6665   Record.AddSourceLocation(C->getLParenLoc());
6666 }
6667 
6668 void OMPClauseWriter::VisitOMPCollapseClause(OMPCollapseClause *C) {
6669   Record.AddStmt(C->getNumForLoops());
6670   Record.AddSourceLocation(C->getLParenLoc());
6671 }
6672 
6673 void OMPClauseWriter::VisitOMPDefaultClause(OMPDefaultClause *C) {
6674   Record.push_back(C->getDefaultKind());
6675   Record.AddSourceLocation(C->getLParenLoc());
6676   Record.AddSourceLocation(C->getDefaultKindKwLoc());
6677 }
6678 
6679 void OMPClauseWriter::VisitOMPProcBindClause(OMPProcBindClause *C) {
6680   Record.push_back(C->getProcBindKind());
6681   Record.AddSourceLocation(C->getLParenLoc());
6682   Record.AddSourceLocation(C->getProcBindKindKwLoc());
6683 }
6684 
6685 void OMPClauseWriter::VisitOMPScheduleClause(OMPScheduleClause *C) {
6686   VisitOMPClauseWithPreInit(C);
6687   Record.push_back(C->getScheduleKind());
6688   Record.push_back(C->getFirstScheduleModifier());
6689   Record.push_back(C->getSecondScheduleModifier());
6690   Record.AddStmt(C->getChunkSize());
6691   Record.AddSourceLocation(C->getLParenLoc());
6692   Record.AddSourceLocation(C->getFirstScheduleModifierLoc());
6693   Record.AddSourceLocation(C->getSecondScheduleModifierLoc());
6694   Record.AddSourceLocation(C->getScheduleKindLoc());
6695   Record.AddSourceLocation(C->getCommaLoc());
6696 }
6697 
6698 void OMPClauseWriter::VisitOMPOrderedClause(OMPOrderedClause *C) {
6699   Record.push_back(C->getLoopNumIterations().size());
6700   Record.AddStmt(C->getNumForLoops());
6701   for (Expr *NumIter : C->getLoopNumIterations())
6702     Record.AddStmt(NumIter);
6703   for (unsigned I = 0, E = C->getLoopNumIterations().size(); I <E; ++I)
6704     Record.AddStmt(C->getLoopCounter(I));
6705   Record.AddSourceLocation(C->getLParenLoc());
6706 }
6707 
6708 void OMPClauseWriter::VisitOMPNowaitClause(OMPNowaitClause *) {}
6709 
6710 void OMPClauseWriter::VisitOMPUntiedClause(OMPUntiedClause *) {}
6711 
6712 void OMPClauseWriter::VisitOMPMergeableClause(OMPMergeableClause *) {}
6713 
6714 void OMPClauseWriter::VisitOMPReadClause(OMPReadClause *) {}
6715 
6716 void OMPClauseWriter::VisitOMPWriteClause(OMPWriteClause *) {}
6717 
6718 void OMPClauseWriter::VisitOMPUpdateClause(OMPUpdateClause *) {}
6719 
6720 void OMPClauseWriter::VisitOMPCaptureClause(OMPCaptureClause *) {}
6721 
6722 void OMPClauseWriter::VisitOMPSeqCstClause(OMPSeqCstClause *) {}
6723 
6724 void OMPClauseWriter::VisitOMPThreadsClause(OMPThreadsClause *) {}
6725 
6726 void OMPClauseWriter::VisitOMPSIMDClause(OMPSIMDClause *) {}
6727 
6728 void OMPClauseWriter::VisitOMPNogroupClause(OMPNogroupClause *) {}
6729 
6730 void OMPClauseWriter::VisitOMPPrivateClause(OMPPrivateClause *C) {
6731   Record.push_back(C->varlist_size());
6732   Record.AddSourceLocation(C->getLParenLoc());
6733   for (auto *VE : C->varlists()) {
6734     Record.AddStmt(VE);
6735   }
6736   for (auto *VE : C->private_copies()) {
6737     Record.AddStmt(VE);
6738   }
6739 }
6740 
6741 void OMPClauseWriter::VisitOMPFirstprivateClause(OMPFirstprivateClause *C) {
6742   Record.push_back(C->varlist_size());
6743   VisitOMPClauseWithPreInit(C);
6744   Record.AddSourceLocation(C->getLParenLoc());
6745   for (auto *VE : C->varlists()) {
6746     Record.AddStmt(VE);
6747   }
6748   for (auto *VE : C->private_copies()) {
6749     Record.AddStmt(VE);
6750   }
6751   for (auto *VE : C->inits()) {
6752     Record.AddStmt(VE);
6753   }
6754 }
6755 
6756 void OMPClauseWriter::VisitOMPLastprivateClause(OMPLastprivateClause *C) {
6757   Record.push_back(C->varlist_size());
6758   VisitOMPClauseWithPostUpdate(C);
6759   Record.AddSourceLocation(C->getLParenLoc());
6760   for (auto *VE : C->varlists())
6761     Record.AddStmt(VE);
6762   for (auto *E : C->private_copies())
6763     Record.AddStmt(E);
6764   for (auto *E : C->source_exprs())
6765     Record.AddStmt(E);
6766   for (auto *E : C->destination_exprs())
6767     Record.AddStmt(E);
6768   for (auto *E : C->assignment_ops())
6769     Record.AddStmt(E);
6770 }
6771 
6772 void OMPClauseWriter::VisitOMPSharedClause(OMPSharedClause *C) {
6773   Record.push_back(C->varlist_size());
6774   Record.AddSourceLocation(C->getLParenLoc());
6775   for (auto *VE : C->varlists())
6776     Record.AddStmt(VE);
6777 }
6778 
6779 void OMPClauseWriter::VisitOMPReductionClause(OMPReductionClause *C) {
6780   Record.push_back(C->varlist_size());
6781   VisitOMPClauseWithPostUpdate(C);
6782   Record.AddSourceLocation(C->getLParenLoc());
6783   Record.AddSourceLocation(C->getColonLoc());
6784   Record.AddNestedNameSpecifierLoc(C->getQualifierLoc());
6785   Record.AddDeclarationNameInfo(C->getNameInfo());
6786   for (auto *VE : C->varlists())
6787     Record.AddStmt(VE);
6788   for (auto *VE : C->privates())
6789     Record.AddStmt(VE);
6790   for (auto *E : C->lhs_exprs())
6791     Record.AddStmt(E);
6792   for (auto *E : C->rhs_exprs())
6793     Record.AddStmt(E);
6794   for (auto *E : C->reduction_ops())
6795     Record.AddStmt(E);
6796 }
6797 
6798 void OMPClauseWriter::VisitOMPTaskReductionClause(OMPTaskReductionClause *C) {
6799   Record.push_back(C->varlist_size());
6800   VisitOMPClauseWithPostUpdate(C);
6801   Record.AddSourceLocation(C->getLParenLoc());
6802   Record.AddSourceLocation(C->getColonLoc());
6803   Record.AddNestedNameSpecifierLoc(C->getQualifierLoc());
6804   Record.AddDeclarationNameInfo(C->getNameInfo());
6805   for (auto *VE : C->varlists())
6806     Record.AddStmt(VE);
6807   for (auto *VE : C->privates())
6808     Record.AddStmt(VE);
6809   for (auto *E : C->lhs_exprs())
6810     Record.AddStmt(E);
6811   for (auto *E : C->rhs_exprs())
6812     Record.AddStmt(E);
6813   for (auto *E : C->reduction_ops())
6814     Record.AddStmt(E);
6815 }
6816 
6817 void OMPClauseWriter::VisitOMPInReductionClause(OMPInReductionClause *C) {
6818   Record.push_back(C->varlist_size());
6819   VisitOMPClauseWithPostUpdate(C);
6820   Record.AddSourceLocation(C->getLParenLoc());
6821   Record.AddSourceLocation(C->getColonLoc());
6822   Record.AddNestedNameSpecifierLoc(C->getQualifierLoc());
6823   Record.AddDeclarationNameInfo(C->getNameInfo());
6824   for (auto *VE : C->varlists())
6825     Record.AddStmt(VE);
6826   for (auto *VE : C->privates())
6827     Record.AddStmt(VE);
6828   for (auto *E : C->lhs_exprs())
6829     Record.AddStmt(E);
6830   for (auto *E : C->rhs_exprs())
6831     Record.AddStmt(E);
6832   for (auto *E : C->reduction_ops())
6833     Record.AddStmt(E);
6834   for (auto *E : C->taskgroup_descriptors())
6835     Record.AddStmt(E);
6836 }
6837 
6838 void OMPClauseWriter::VisitOMPLinearClause(OMPLinearClause *C) {
6839   Record.push_back(C->varlist_size());
6840   VisitOMPClauseWithPostUpdate(C);
6841   Record.AddSourceLocation(C->getLParenLoc());
6842   Record.AddSourceLocation(C->getColonLoc());
6843   Record.push_back(C->getModifier());
6844   Record.AddSourceLocation(C->getModifierLoc());
6845   for (auto *VE : C->varlists()) {
6846     Record.AddStmt(VE);
6847   }
6848   for (auto *VE : C->privates()) {
6849     Record.AddStmt(VE);
6850   }
6851   for (auto *VE : C->inits()) {
6852     Record.AddStmt(VE);
6853   }
6854   for (auto *VE : C->updates()) {
6855     Record.AddStmt(VE);
6856   }
6857   for (auto *VE : C->finals()) {
6858     Record.AddStmt(VE);
6859   }
6860   Record.AddStmt(C->getStep());
6861   Record.AddStmt(C->getCalcStep());
6862   for (auto *VE : C->used_expressions())
6863     Record.AddStmt(VE);
6864 }
6865 
6866 void OMPClauseWriter::VisitOMPAlignedClause(OMPAlignedClause *C) {
6867   Record.push_back(C->varlist_size());
6868   Record.AddSourceLocation(C->getLParenLoc());
6869   Record.AddSourceLocation(C->getColonLoc());
6870   for (auto *VE : C->varlists())
6871     Record.AddStmt(VE);
6872   Record.AddStmt(C->getAlignment());
6873 }
6874 
6875 void OMPClauseWriter::VisitOMPCopyinClause(OMPCopyinClause *C) {
6876   Record.push_back(C->varlist_size());
6877   Record.AddSourceLocation(C->getLParenLoc());
6878   for (auto *VE : C->varlists())
6879     Record.AddStmt(VE);
6880   for (auto *E : C->source_exprs())
6881     Record.AddStmt(E);
6882   for (auto *E : C->destination_exprs())
6883     Record.AddStmt(E);
6884   for (auto *E : C->assignment_ops())
6885     Record.AddStmt(E);
6886 }
6887 
6888 void OMPClauseWriter::VisitOMPCopyprivateClause(OMPCopyprivateClause *C) {
6889   Record.push_back(C->varlist_size());
6890   Record.AddSourceLocation(C->getLParenLoc());
6891   for (auto *VE : C->varlists())
6892     Record.AddStmt(VE);
6893   for (auto *E : C->source_exprs())
6894     Record.AddStmt(E);
6895   for (auto *E : C->destination_exprs())
6896     Record.AddStmt(E);
6897   for (auto *E : C->assignment_ops())
6898     Record.AddStmt(E);
6899 }
6900 
6901 void OMPClauseWriter::VisitOMPFlushClause(OMPFlushClause *C) {
6902   Record.push_back(C->varlist_size());
6903   Record.AddSourceLocation(C->getLParenLoc());
6904   for (auto *VE : C->varlists())
6905     Record.AddStmt(VE);
6906 }
6907 
6908 void OMPClauseWriter::VisitOMPDependClause(OMPDependClause *C) {
6909   Record.push_back(C->varlist_size());
6910   Record.push_back(C->getNumLoops());
6911   Record.AddSourceLocation(C->getLParenLoc());
6912   Record.push_back(C->getDependencyKind());
6913   Record.AddSourceLocation(C->getDependencyLoc());
6914   Record.AddSourceLocation(C->getColonLoc());
6915   for (auto *VE : C->varlists())
6916     Record.AddStmt(VE);
6917   for (unsigned I = 0, E = C->getNumLoops(); I < E; ++I)
6918     Record.AddStmt(C->getLoopData(I));
6919 }
6920 
6921 void OMPClauseWriter::VisitOMPDeviceClause(OMPDeviceClause *C) {
6922   VisitOMPClauseWithPreInit(C);
6923   Record.AddStmt(C->getDevice());
6924   Record.AddSourceLocation(C->getLParenLoc());
6925 }
6926 
6927 void OMPClauseWriter::VisitOMPMapClause(OMPMapClause *C) {
6928   Record.push_back(C->varlist_size());
6929   Record.push_back(C->getUniqueDeclarationsNum());
6930   Record.push_back(C->getTotalComponentListNum());
6931   Record.push_back(C->getTotalComponentsNum());
6932   Record.AddSourceLocation(C->getLParenLoc());
6933   for (unsigned I = 0; I < OMPMapClause::NumberOfModifiers; ++I) {
6934     Record.push_back(C->getMapTypeModifier(I));
6935     Record.AddSourceLocation(C->getMapTypeModifierLoc(I));
6936   }
6937   Record.AddNestedNameSpecifierLoc(C->getMapperQualifierLoc());
6938   Record.AddDeclarationNameInfo(C->getMapperIdInfo());
6939   Record.push_back(C->getMapType());
6940   Record.AddSourceLocation(C->getMapLoc());
6941   Record.AddSourceLocation(C->getColonLoc());
6942   for (auto *E : C->varlists())
6943     Record.AddStmt(E);
6944   for (auto *E : C->mapperlists())
6945     Record.AddStmt(E);
6946   for (auto *D : C->all_decls())
6947     Record.AddDeclRef(D);
6948   for (auto N : C->all_num_lists())
6949     Record.push_back(N);
6950   for (auto N : C->all_lists_sizes())
6951     Record.push_back(N);
6952   for (auto &M : C->all_components()) {
6953     Record.AddStmt(M.getAssociatedExpression());
6954     Record.AddDeclRef(M.getAssociatedDeclaration());
6955   }
6956 }
6957 
6958 void OMPClauseWriter::VisitOMPAllocateClause(OMPAllocateClause *C) {
6959   Record.push_back(C->varlist_size());
6960   Record.AddSourceLocation(C->getLParenLoc());
6961   Record.AddSourceLocation(C->getColonLoc());
6962   Record.AddStmt(C->getAllocator());
6963   for (auto *VE : C->varlists())
6964     Record.AddStmt(VE);
6965 }
6966 
6967 void OMPClauseWriter::VisitOMPNumTeamsClause(OMPNumTeamsClause *C) {
6968   VisitOMPClauseWithPreInit(C);
6969   Record.AddStmt(C->getNumTeams());
6970   Record.AddSourceLocation(C->getLParenLoc());
6971 }
6972 
6973 void OMPClauseWriter::VisitOMPThreadLimitClause(OMPThreadLimitClause *C) {
6974   VisitOMPClauseWithPreInit(C);
6975   Record.AddStmt(C->getThreadLimit());
6976   Record.AddSourceLocation(C->getLParenLoc());
6977 }
6978 
6979 void OMPClauseWriter::VisitOMPPriorityClause(OMPPriorityClause *C) {
6980   VisitOMPClauseWithPreInit(C);
6981   Record.AddStmt(C->getPriority());
6982   Record.AddSourceLocation(C->getLParenLoc());
6983 }
6984 
6985 void OMPClauseWriter::VisitOMPGrainsizeClause(OMPGrainsizeClause *C) {
6986   VisitOMPClauseWithPreInit(C);
6987   Record.AddStmt(C->getGrainsize());
6988   Record.AddSourceLocation(C->getLParenLoc());
6989 }
6990 
6991 void OMPClauseWriter::VisitOMPNumTasksClause(OMPNumTasksClause *C) {
6992   VisitOMPClauseWithPreInit(C);
6993   Record.AddStmt(C->getNumTasks());
6994   Record.AddSourceLocation(C->getLParenLoc());
6995 }
6996 
6997 void OMPClauseWriter::VisitOMPHintClause(OMPHintClause *C) {
6998   Record.AddStmt(C->getHint());
6999   Record.AddSourceLocation(C->getLParenLoc());
7000 }
7001 
7002 void OMPClauseWriter::VisitOMPDistScheduleClause(OMPDistScheduleClause *C) {
7003   VisitOMPClauseWithPreInit(C);
7004   Record.push_back(C->getDistScheduleKind());
7005   Record.AddStmt(C->getChunkSize());
7006   Record.AddSourceLocation(C->getLParenLoc());
7007   Record.AddSourceLocation(C->getDistScheduleKindLoc());
7008   Record.AddSourceLocation(C->getCommaLoc());
7009 }
7010 
7011 void OMPClauseWriter::VisitOMPDefaultmapClause(OMPDefaultmapClause *C) {
7012   Record.push_back(C->getDefaultmapKind());
7013   Record.push_back(C->getDefaultmapModifier());
7014   Record.AddSourceLocation(C->getLParenLoc());
7015   Record.AddSourceLocation(C->getDefaultmapModifierLoc());
7016   Record.AddSourceLocation(C->getDefaultmapKindLoc());
7017 }
7018 
7019 void OMPClauseWriter::VisitOMPToClause(OMPToClause *C) {
7020   Record.push_back(C->varlist_size());
7021   Record.push_back(C->getUniqueDeclarationsNum());
7022   Record.push_back(C->getTotalComponentListNum());
7023   Record.push_back(C->getTotalComponentsNum());
7024   Record.AddSourceLocation(C->getLParenLoc());
7025   Record.AddNestedNameSpecifierLoc(C->getMapperQualifierLoc());
7026   Record.AddDeclarationNameInfo(C->getMapperIdInfo());
7027   for (auto *E : C->varlists())
7028     Record.AddStmt(E);
7029   for (auto *E : C->mapperlists())
7030     Record.AddStmt(E);
7031   for (auto *D : C->all_decls())
7032     Record.AddDeclRef(D);
7033   for (auto N : C->all_num_lists())
7034     Record.push_back(N);
7035   for (auto N : C->all_lists_sizes())
7036     Record.push_back(N);
7037   for (auto &M : C->all_components()) {
7038     Record.AddStmt(M.getAssociatedExpression());
7039     Record.AddDeclRef(M.getAssociatedDeclaration());
7040   }
7041 }
7042 
7043 void OMPClauseWriter::VisitOMPFromClause(OMPFromClause *C) {
7044   Record.push_back(C->varlist_size());
7045   Record.push_back(C->getUniqueDeclarationsNum());
7046   Record.push_back(C->getTotalComponentListNum());
7047   Record.push_back(C->getTotalComponentsNum());
7048   Record.AddSourceLocation(C->getLParenLoc());
7049   Record.AddNestedNameSpecifierLoc(C->getMapperQualifierLoc());
7050   Record.AddDeclarationNameInfo(C->getMapperIdInfo());
7051   for (auto *E : C->varlists())
7052     Record.AddStmt(E);
7053   for (auto *E : C->mapperlists())
7054     Record.AddStmt(E);
7055   for (auto *D : C->all_decls())
7056     Record.AddDeclRef(D);
7057   for (auto N : C->all_num_lists())
7058     Record.push_back(N);
7059   for (auto N : C->all_lists_sizes())
7060     Record.push_back(N);
7061   for (auto &M : C->all_components()) {
7062     Record.AddStmt(M.getAssociatedExpression());
7063     Record.AddDeclRef(M.getAssociatedDeclaration());
7064   }
7065 }
7066 
7067 void OMPClauseWriter::VisitOMPUseDevicePtrClause(OMPUseDevicePtrClause *C) {
7068   Record.push_back(C->varlist_size());
7069   Record.push_back(C->getUniqueDeclarationsNum());
7070   Record.push_back(C->getTotalComponentListNum());
7071   Record.push_back(C->getTotalComponentsNum());
7072   Record.AddSourceLocation(C->getLParenLoc());
7073   for (auto *E : C->varlists())
7074     Record.AddStmt(E);
7075   for (auto *VE : C->private_copies())
7076     Record.AddStmt(VE);
7077   for (auto *VE : C->inits())
7078     Record.AddStmt(VE);
7079   for (auto *D : C->all_decls())
7080     Record.AddDeclRef(D);
7081   for (auto N : C->all_num_lists())
7082     Record.push_back(N);
7083   for (auto N : C->all_lists_sizes())
7084     Record.push_back(N);
7085   for (auto &M : C->all_components()) {
7086     Record.AddStmt(M.getAssociatedExpression());
7087     Record.AddDeclRef(M.getAssociatedDeclaration());
7088   }
7089 }
7090 
7091 void OMPClauseWriter::VisitOMPIsDevicePtrClause(OMPIsDevicePtrClause *C) {
7092   Record.push_back(C->varlist_size());
7093   Record.push_back(C->getUniqueDeclarationsNum());
7094   Record.push_back(C->getTotalComponentListNum());
7095   Record.push_back(C->getTotalComponentsNum());
7096   Record.AddSourceLocation(C->getLParenLoc());
7097   for (auto *E : C->varlists())
7098     Record.AddStmt(E);
7099   for (auto *D : C->all_decls())
7100     Record.AddDeclRef(D);
7101   for (auto N : C->all_num_lists())
7102     Record.push_back(N);
7103   for (auto N : C->all_lists_sizes())
7104     Record.push_back(N);
7105   for (auto &M : C->all_components()) {
7106     Record.AddStmt(M.getAssociatedExpression());
7107     Record.AddDeclRef(M.getAssociatedDeclaration());
7108   }
7109 }
7110 
7111 void OMPClauseWriter::VisitOMPUnifiedAddressClause(OMPUnifiedAddressClause *) {}
7112 
7113 void OMPClauseWriter::VisitOMPUnifiedSharedMemoryClause(
7114     OMPUnifiedSharedMemoryClause *) {}
7115 
7116 void OMPClauseWriter::VisitOMPReverseOffloadClause(OMPReverseOffloadClause *) {}
7117 
7118 void
7119 OMPClauseWriter::VisitOMPDynamicAllocatorsClause(OMPDynamicAllocatorsClause *) {
7120 }
7121 
7122 void OMPClauseWriter::VisitOMPAtomicDefaultMemOrderClause(
7123     OMPAtomicDefaultMemOrderClause *C) {
7124   Record.push_back(C->getAtomicDefaultMemOrderKind());
7125   Record.AddSourceLocation(C->getLParenLoc());
7126   Record.AddSourceLocation(C->getAtomicDefaultMemOrderKindKwLoc());
7127 }
7128