1 //===-- SymbolFileNativePDB.cpp ---------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "SymbolFileNativePDB.h"
11 
12 #include "clang/AST/Attr.h"
13 #include "clang/AST/CharUnits.h"
14 #include "clang/AST/Decl.h"
15 #include "clang/AST/DeclCXX.h"
16 #include "clang/AST/Type.h"
17 
18 #include "lldb/Core/Module.h"
19 #include "lldb/Core/PluginManager.h"
20 #include "lldb/Core/StreamBuffer.h"
21 #include "lldb/Core/StreamFile.h"
22 #include "lldb/Symbol/ClangASTContext.h"
23 #include "lldb/Symbol/ClangASTImporter.h"
24 #include "lldb/Symbol/ClangExternalASTSourceCommon.h"
25 #include "lldb/Symbol/ClangUtil.h"
26 #include "lldb/Symbol/CompileUnit.h"
27 #include "lldb/Symbol/LineTable.h"
28 #include "lldb/Symbol/ObjectFile.h"
29 #include "lldb/Symbol/SymbolContext.h"
30 #include "lldb/Symbol/SymbolVendor.h"
31 #include "lldb/Symbol/Variable.h"
32 #include "lldb/Symbol/VariableList.h"
33 
34 #include "llvm/DebugInfo/CodeView/CVRecord.h"
35 #include "llvm/DebugInfo/CodeView/CVTypeVisitor.h"
36 #include "llvm/DebugInfo/CodeView/DebugLinesSubsection.h"
37 #include "llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h"
38 #include "llvm/DebugInfo/CodeView/RecordName.h"
39 #include "llvm/DebugInfo/CodeView/SymbolDeserializer.h"
40 #include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
41 #include "llvm/DebugInfo/PDB/Native/DbiStream.h"
42 #include "llvm/DebugInfo/PDB/Native/GlobalsStream.h"
43 #include "llvm/DebugInfo/PDB/Native/InfoStream.h"
44 #include "llvm/DebugInfo/PDB/Native/ModuleDebugStream.h"
45 #include "llvm/DebugInfo/PDB/Native/PDBFile.h"
46 #include "llvm/DebugInfo/PDB/Native/SymbolStream.h"
47 #include "llvm/DebugInfo/PDB/Native/TpiStream.h"
48 #include "llvm/DebugInfo/PDB/PDBTypes.h"
49 #include "llvm/Demangle/MicrosoftDemangle.h"
50 #include "llvm/Object/COFF.h"
51 #include "llvm/Support/Allocator.h"
52 #include "llvm/Support/BinaryStreamReader.h"
53 #include "llvm/Support/Error.h"
54 #include "llvm/Support/ErrorOr.h"
55 #include "llvm/Support/MemoryBuffer.h"
56 
57 #include "PdbSymUid.h"
58 #include "PdbUtil.h"
59 #include "UdtRecordCompleter.h"
60 
61 using namespace lldb;
62 using namespace lldb_private;
63 using namespace npdb;
64 using namespace llvm::codeview;
65 using namespace llvm::pdb;
66 
67 static lldb::LanguageType TranslateLanguage(PDB_Lang lang) {
68   switch (lang) {
69   case PDB_Lang::Cpp:
70     return lldb::LanguageType::eLanguageTypeC_plus_plus;
71   case PDB_Lang::C:
72     return lldb::LanguageType::eLanguageTypeC;
73   default:
74     return lldb::LanguageType::eLanguageTypeUnknown;
75   }
76 }
77 
78 static std::unique_ptr<PDBFile> loadPDBFile(std::string PdbPath,
79                                             llvm::BumpPtrAllocator &Allocator) {
80   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> ErrorOrBuffer =
81       llvm::MemoryBuffer::getFile(PdbPath, /*FileSize=*/-1,
82                                   /*RequiresNullTerminator=*/false);
83   if (!ErrorOrBuffer)
84     return nullptr;
85   std::unique_ptr<llvm::MemoryBuffer> Buffer = std::move(*ErrorOrBuffer);
86 
87   llvm::StringRef Path = Buffer->getBufferIdentifier();
88   auto Stream = llvm::make_unique<llvm::MemoryBufferByteStream>(
89       std::move(Buffer), llvm::support::little);
90 
91   auto File = llvm::make_unique<PDBFile>(Path, std::move(Stream), Allocator);
92   if (auto EC = File->parseFileHeaders()) {
93     llvm::consumeError(std::move(EC));
94     return nullptr;
95   }
96   if (auto EC = File->parseStreamData()) {
97     llvm::consumeError(std::move(EC));
98     return nullptr;
99   }
100 
101   return File;
102 }
103 
104 static std::unique_ptr<PDBFile>
105 loadMatchingPDBFile(std::string exe_path, llvm::BumpPtrAllocator &allocator) {
106   // Try to find a matching PDB for an EXE.
107   using namespace llvm::object;
108   auto expected_binary = createBinary(exe_path);
109 
110   // If the file isn't a PE/COFF executable, fail.
111   if (!expected_binary) {
112     llvm::consumeError(expected_binary.takeError());
113     return nullptr;
114   }
115   OwningBinary<Binary> binary = std::move(*expected_binary);
116 
117   auto *obj = llvm::dyn_cast<llvm::object::COFFObjectFile>(binary.getBinary());
118   if (!obj)
119     return nullptr;
120   const llvm::codeview::DebugInfo *pdb_info = nullptr;
121 
122   // If it doesn't have a debug directory, fail.
123   llvm::StringRef pdb_file;
124   auto ec = obj->getDebugPDBInfo(pdb_info, pdb_file);
125   if (ec)
126     return nullptr;
127 
128   // if the file doesn't exist, is not a pdb, or doesn't have a matching guid,
129   // fail.
130   llvm::file_magic magic;
131   ec = llvm::identify_magic(pdb_file, magic);
132   if (ec || magic != llvm::file_magic::pdb)
133     return nullptr;
134   std::unique_ptr<PDBFile> pdb = loadPDBFile(pdb_file, allocator);
135   if (!pdb)
136     return nullptr;
137 
138   auto expected_info = pdb->getPDBInfoStream();
139   if (!expected_info) {
140     llvm::consumeError(expected_info.takeError());
141     return nullptr;
142   }
143   llvm::codeview::GUID guid;
144   memcpy(&guid, pdb_info->PDB70.Signature, 16);
145 
146   if (expected_info->getGuid() != guid)
147     return nullptr;
148   return pdb;
149 }
150 
151 static bool IsFunctionPrologue(const CompilandIndexItem &cci,
152                                lldb::addr_t addr) {
153   // FIXME: Implement this.
154   return false;
155 }
156 
157 static bool IsFunctionEpilogue(const CompilandIndexItem &cci,
158                                lldb::addr_t addr) {
159   // FIXME: Implement this.
160   return false;
161 }
162 
163 static clang::MSInheritanceAttr::Spelling
164 GetMSInheritance(LazyRandomTypeCollection &tpi, const ClassRecord &record) {
165   if (record.DerivationList == TypeIndex::None())
166     return clang::MSInheritanceAttr::Spelling::Keyword_single_inheritance;
167 
168   CVType bases = tpi.getType(record.DerivationList);
169   ArgListRecord base_list;
170   cantFail(TypeDeserializer::deserializeAs<ArgListRecord>(bases, base_list));
171   if (base_list.ArgIndices.empty())
172     return clang::MSInheritanceAttr::Spelling::Keyword_single_inheritance;
173 
174   int base_count = 0;
175   for (TypeIndex ti : base_list.ArgIndices) {
176     CVType base = tpi.getType(ti);
177     if (base.kind() == LF_VBCLASS || base.kind() == LF_IVBCLASS)
178       return clang::MSInheritanceAttr::Spelling::Keyword_virtual_inheritance;
179     ++base_count;
180   }
181 
182   if (base_count > 1)
183     return clang::MSInheritanceAttr::Keyword_multiple_inheritance;
184   return clang::MSInheritanceAttr::Keyword_single_inheritance;
185 }
186 
187 static lldb::BasicType GetCompilerTypeForSimpleKind(SimpleTypeKind kind) {
188   switch (kind) {
189   case SimpleTypeKind::Boolean128:
190   case SimpleTypeKind::Boolean16:
191   case SimpleTypeKind::Boolean32:
192   case SimpleTypeKind::Boolean64:
193   case SimpleTypeKind::Boolean8:
194     return lldb::eBasicTypeBool;
195   case SimpleTypeKind::Byte:
196   case SimpleTypeKind::UnsignedCharacter:
197     return lldb::eBasicTypeUnsignedChar;
198   case SimpleTypeKind::NarrowCharacter:
199     return lldb::eBasicTypeChar;
200   case SimpleTypeKind::SignedCharacter:
201   case SimpleTypeKind::SByte:
202     return lldb::eBasicTypeSignedChar;
203   case SimpleTypeKind::Character16:
204     return lldb::eBasicTypeChar16;
205   case SimpleTypeKind::Character32:
206     return lldb::eBasicTypeChar32;
207   case SimpleTypeKind::Complex80:
208     return lldb::eBasicTypeLongDoubleComplex;
209   case SimpleTypeKind::Complex64:
210     return lldb::eBasicTypeDoubleComplex;
211   case SimpleTypeKind::Complex32:
212     return lldb::eBasicTypeFloatComplex;
213   case SimpleTypeKind::Float128:
214   case SimpleTypeKind::Float80:
215     return lldb::eBasicTypeLongDouble;
216   case SimpleTypeKind::Float64:
217     return lldb::eBasicTypeDouble;
218   case SimpleTypeKind::Float32:
219     return lldb::eBasicTypeFloat;
220   case SimpleTypeKind::Float16:
221     return lldb::eBasicTypeHalf;
222   case SimpleTypeKind::Int128:
223     return lldb::eBasicTypeInt128;
224   case SimpleTypeKind::Int64:
225   case SimpleTypeKind::Int64Quad:
226     return lldb::eBasicTypeLongLong;
227   case SimpleTypeKind::Int32:
228     return lldb::eBasicTypeInt;
229   case SimpleTypeKind::Int16:
230   case SimpleTypeKind::Int16Short:
231     return lldb::eBasicTypeShort;
232   case SimpleTypeKind::UInt128:
233     return lldb::eBasicTypeUnsignedInt128;
234   case SimpleTypeKind::UInt64:
235   case SimpleTypeKind::UInt64Quad:
236     return lldb::eBasicTypeUnsignedLongLong;
237   case SimpleTypeKind::HResult:
238   case SimpleTypeKind::UInt32:
239     return lldb::eBasicTypeUnsignedInt;
240   case SimpleTypeKind::UInt16:
241   case SimpleTypeKind::UInt16Short:
242     return lldb::eBasicTypeUnsignedShort;
243   case SimpleTypeKind::Int32Long:
244     return lldb::eBasicTypeLong;
245   case SimpleTypeKind::UInt32Long:
246     return lldb::eBasicTypeUnsignedLong;
247   case SimpleTypeKind::Void:
248     return lldb::eBasicTypeVoid;
249   case SimpleTypeKind::WideCharacter:
250     return lldb::eBasicTypeWChar;
251   default:
252     return lldb::eBasicTypeInvalid;
253   }
254 }
255 
256 static bool IsSimpleTypeSignedInteger(SimpleTypeKind kind) {
257   switch (kind) {
258   case SimpleTypeKind::Int128:
259   case SimpleTypeKind::Int64:
260   case SimpleTypeKind::Int64Quad:
261   case SimpleTypeKind::Int32:
262   case SimpleTypeKind::Int32Long:
263   case SimpleTypeKind::Int16:
264   case SimpleTypeKind::Int16Short:
265   case SimpleTypeKind::Float128:
266   case SimpleTypeKind::Float80:
267   case SimpleTypeKind::Float64:
268   case SimpleTypeKind::Float32:
269   case SimpleTypeKind::Float16:
270   case SimpleTypeKind::NarrowCharacter:
271   case SimpleTypeKind::SignedCharacter:
272   case SimpleTypeKind::SByte:
273     return true;
274   default:
275     return false;
276   }
277 }
278 
279 static size_t GetTypeSizeForSimpleKind(SimpleTypeKind kind) {
280   switch (kind) {
281   case SimpleTypeKind::Boolean128:
282   case SimpleTypeKind::Int128:
283   case SimpleTypeKind::UInt128:
284   case SimpleTypeKind::Float128:
285     return 16;
286   case SimpleTypeKind::Complex80:
287   case SimpleTypeKind::Float80:
288     return 10;
289   case SimpleTypeKind::Boolean64:
290   case SimpleTypeKind::Complex64:
291   case SimpleTypeKind::UInt64:
292   case SimpleTypeKind::UInt64Quad:
293   case SimpleTypeKind::Float64:
294   case SimpleTypeKind::Int64:
295   case SimpleTypeKind::Int64Quad:
296     return 8;
297   case SimpleTypeKind::Boolean32:
298   case SimpleTypeKind::Character32:
299   case SimpleTypeKind::Complex32:
300   case SimpleTypeKind::Float32:
301   case SimpleTypeKind::Int32:
302   case SimpleTypeKind::Int32Long:
303   case SimpleTypeKind::UInt32Long:
304   case SimpleTypeKind::HResult:
305   case SimpleTypeKind::UInt32:
306     return 4;
307   case SimpleTypeKind::Boolean16:
308   case SimpleTypeKind::Character16:
309   case SimpleTypeKind::Float16:
310   case SimpleTypeKind::Int16:
311   case SimpleTypeKind::Int16Short:
312   case SimpleTypeKind::UInt16:
313   case SimpleTypeKind::UInt16Short:
314   case SimpleTypeKind::WideCharacter:
315     return 2;
316   case SimpleTypeKind::Boolean8:
317   case SimpleTypeKind::Byte:
318   case SimpleTypeKind::UnsignedCharacter:
319   case SimpleTypeKind::NarrowCharacter:
320   case SimpleTypeKind::SignedCharacter:
321   case SimpleTypeKind::SByte:
322     return 1;
323   case SimpleTypeKind::Void:
324   default:
325     return 0;
326   }
327 }
328 
329 std::pair<size_t, bool> GetIntegralTypeInfo(TypeIndex ti, TpiStream &tpi) {
330   if (ti.isSimple()) {
331     SimpleTypeKind stk = ti.getSimpleKind();
332     return {GetTypeSizeForSimpleKind(stk), IsSimpleTypeSignedInteger(stk)};
333   }
334 
335   CVType cvt = tpi.getType(ti);
336   switch (cvt.kind()) {
337   case LF_MODIFIER: {
338     ModifierRecord mfr;
339     llvm::cantFail(TypeDeserializer::deserializeAs<ModifierRecord>(cvt, mfr));
340     return GetIntegralTypeInfo(mfr.ModifiedType, tpi);
341   }
342   case LF_POINTER: {
343     PointerRecord pr;
344     llvm::cantFail(TypeDeserializer::deserializeAs<PointerRecord>(cvt, pr));
345     return GetIntegralTypeInfo(pr.ReferentType, tpi);
346   }
347   case LF_ENUM: {
348     EnumRecord er;
349     llvm::cantFail(TypeDeserializer::deserializeAs<EnumRecord>(cvt, er));
350     return GetIntegralTypeInfo(er.UnderlyingType, tpi);
351   }
352   default:
353     assert(false && "Type is not integral!");
354     return {0, false};
355   }
356 }
357 
358 static llvm::StringRef GetSimpleTypeName(SimpleTypeKind kind) {
359   switch (kind) {
360   case SimpleTypeKind::Boolean128:
361   case SimpleTypeKind::Boolean16:
362   case SimpleTypeKind::Boolean32:
363   case SimpleTypeKind::Boolean64:
364   case SimpleTypeKind::Boolean8:
365     return "bool";
366   case SimpleTypeKind::Byte:
367   case SimpleTypeKind::UnsignedCharacter:
368     return "unsigned char";
369   case SimpleTypeKind::NarrowCharacter:
370     return "char";
371   case SimpleTypeKind::SignedCharacter:
372   case SimpleTypeKind::SByte:
373     return "signed char";
374   case SimpleTypeKind::Character16:
375     return "char16_t";
376   case SimpleTypeKind::Character32:
377     return "char32_t";
378   case SimpleTypeKind::Complex80:
379   case SimpleTypeKind::Complex64:
380   case SimpleTypeKind::Complex32:
381     return "complex";
382   case SimpleTypeKind::Float128:
383   case SimpleTypeKind::Float80:
384     return "long double";
385   case SimpleTypeKind::Float64:
386     return "double";
387   case SimpleTypeKind::Float32:
388     return "float";
389   case SimpleTypeKind::Float16:
390     return "single";
391   case SimpleTypeKind::Int128:
392     return "__int128";
393   case SimpleTypeKind::Int64:
394   case SimpleTypeKind::Int64Quad:
395     return "int64_t";
396   case SimpleTypeKind::Int32:
397     return "int";
398   case SimpleTypeKind::Int16:
399     return "short";
400   case SimpleTypeKind::UInt128:
401     return "unsigned __int128";
402   case SimpleTypeKind::UInt64:
403   case SimpleTypeKind::UInt64Quad:
404     return "uint64_t";
405   case SimpleTypeKind::HResult:
406     return "HRESULT";
407   case SimpleTypeKind::UInt32:
408     return "unsigned";
409   case SimpleTypeKind::UInt16:
410   case SimpleTypeKind::UInt16Short:
411     return "unsigned short";
412   case SimpleTypeKind::Int32Long:
413     return "long";
414   case SimpleTypeKind::UInt32Long:
415     return "unsigned long";
416   case SimpleTypeKind::Void:
417     return "void";
418   case SimpleTypeKind::WideCharacter:
419     return "wchar_t";
420   default:
421     return "";
422   }
423 }
424 
425 static bool IsClassRecord(TypeLeafKind kind) {
426   switch (kind) {
427   case LF_STRUCTURE:
428   case LF_CLASS:
429   case LF_INTERFACE:
430     return true;
431   default:
432     return false;
433   }
434 }
435 
436 static PDB_SymType GetPdbSymType(TpiStream &tpi, TypeIndex ti) {
437   if (ti.isSimple()) {
438     if (ti.getSimpleMode() == SimpleTypeMode::Direct)
439       return PDB_SymType::BuiltinType;
440     return PDB_SymType::PointerType;
441   }
442 
443   CVType cvt = tpi.getType(ti);
444   TypeLeafKind kind = cvt.kind();
445   if (kind != LF_MODIFIER)
446     return CVTypeToPDBType(kind);
447 
448   // If this is an LF_MODIFIER, look through it to get the kind that it
449   // modifies.  Note that it's not possible to have an LF_MODIFIER that
450   // modifies another LF_MODIFIER, although this would handle that anyway.
451   return GetPdbSymType(tpi, LookThroughModifierRecord(cvt));
452 }
453 
454 static bool IsCVarArgsFunction(llvm::ArrayRef<TypeIndex> args) {
455   if (args.empty())
456     return false;
457   return args.back() == TypeIndex::None();
458 }
459 
460 static clang::TagTypeKind TranslateUdtKind(const TagRecord &cr) {
461   switch (cr.Kind) {
462   case TypeRecordKind::Class:
463     return clang::TTK_Class;
464   case TypeRecordKind::Struct:
465     return clang::TTK_Struct;
466   case TypeRecordKind::Union:
467     return clang::TTK_Union;
468   case TypeRecordKind::Interface:
469     return clang::TTK_Interface;
470   case TypeRecordKind::Enum:
471     return clang::TTK_Enum;
472   default:
473     lldbassert(false && "Invalid tag record kind!");
474     return clang::TTK_Struct;
475   }
476 }
477 
478 static llvm::Optional<clang::CallingConv>
479 TranslateCallingConvention(llvm::codeview::CallingConvention conv) {
480   using CC = llvm::codeview::CallingConvention;
481   switch (conv) {
482 
483   case CC::NearC:
484   case CC::FarC:
485     return clang::CallingConv::CC_C;
486   case CC::NearPascal:
487   case CC::FarPascal:
488     return clang::CallingConv::CC_X86Pascal;
489   case CC::NearFast:
490   case CC::FarFast:
491     return clang::CallingConv::CC_X86FastCall;
492   case CC::NearStdCall:
493   case CC::FarStdCall:
494     return clang::CallingConv::CC_X86StdCall;
495   case CC::ThisCall:
496     return clang::CallingConv::CC_X86ThisCall;
497   case CC::NearVector:
498     return clang::CallingConv::CC_X86VectorCall;
499   default:
500     return llvm::None;
501   }
502 }
503 
504 void SymbolFileNativePDB::Initialize() {
505   PluginManager::RegisterPlugin(GetPluginNameStatic(),
506                                 GetPluginDescriptionStatic(), CreateInstance,
507                                 DebuggerInitialize);
508 }
509 
510 void SymbolFileNativePDB::Terminate() {
511   PluginManager::UnregisterPlugin(CreateInstance);
512 }
513 
514 void SymbolFileNativePDB::DebuggerInitialize(Debugger &debugger) {}
515 
516 ConstString SymbolFileNativePDB::GetPluginNameStatic() {
517   static ConstString g_name("native-pdb");
518   return g_name;
519 }
520 
521 const char *SymbolFileNativePDB::GetPluginDescriptionStatic() {
522   return "Microsoft PDB debug symbol cross-platform file reader.";
523 }
524 
525 SymbolFile *SymbolFileNativePDB::CreateInstance(ObjectFile *obj_file) {
526   return new SymbolFileNativePDB(obj_file);
527 }
528 
529 SymbolFileNativePDB::SymbolFileNativePDB(ObjectFile *object_file)
530     : SymbolFile(object_file) {}
531 
532 SymbolFileNativePDB::~SymbolFileNativePDB() {}
533 
534 uint32_t SymbolFileNativePDB::CalculateAbilities() {
535   uint32_t abilities = 0;
536   if (!m_obj_file)
537     return 0;
538 
539   if (!m_index) {
540     // Lazily load and match the PDB file, but only do this once.
541     std::unique_ptr<PDBFile> file_up =
542         loadMatchingPDBFile(m_obj_file->GetFileSpec().GetPath(), m_allocator);
543 
544     if (!file_up) {
545       auto module_sp = m_obj_file->GetModule();
546       if (!module_sp)
547         return 0;
548       // See if any symbol file is specified through `--symfile` option.
549       FileSpec symfile = module_sp->GetSymbolFileFileSpec();
550       if (!symfile)
551         return 0;
552       file_up = loadPDBFile(symfile.GetPath(), m_allocator);
553     }
554 
555     if (!file_up)
556       return 0;
557 
558     auto expected_index = PdbIndex::create(std::move(file_up));
559     if (!expected_index) {
560       llvm::consumeError(expected_index.takeError());
561       return 0;
562     }
563     m_index = std::move(*expected_index);
564   }
565   if (!m_index)
566     return 0;
567 
568   // We don't especially have to be precise here.  We only distinguish between
569   // stripped and not stripped.
570   abilities = kAllAbilities;
571 
572   if (m_index->dbi().isStripped())
573     abilities &= ~(Blocks | LocalVariables);
574   return abilities;
575 }
576 
577 void SymbolFileNativePDB::InitializeObject() {
578   m_obj_load_address = m_obj_file->GetFileOffset();
579   m_index->SetLoadAddress(m_obj_load_address);
580   m_index->ParseSectionContribs();
581 
582   TypeSystem *ts = GetTypeSystemForLanguage(eLanguageTypeC_plus_plus);
583   m_clang = llvm::dyn_cast_or_null<ClangASTContext>(ts);
584   m_importer = llvm::make_unique<ClangASTImporter>();
585 
586   PreprocessTpiStream();
587   lldbassert(m_clang);
588 }
589 
590 static llvm::Optional<CVTagRecord>
591 GetNestedTagRecord(const NestedTypeRecord &Record, const CVTagRecord &parent,
592                    TpiStream &tpi) {
593   // An LF_NESTTYPE is essentially a nested typedef / using declaration, but it
594   // is also used to indicate the primary definition of a nested class.  That is
595   // to say, if you have:
596   // struct A {
597   //   struct B {};
598   //   using C = B;
599   // };
600   // Then in the debug info, this will appear as:
601   // LF_STRUCTURE `A::B` [type index = N]
602   // LF_STRUCTURE `A`
603   //   LF_NESTTYPE [name = `B`, index = N]
604   //   LF_NESTTYPE [name = `C`, index = N]
605   // In order to accurately reconstruct the decl context hierarchy, we need to
606   // know which ones are actual definitions and which ones are just aliases.
607 
608   // If it's a simple type, then this is something like `using foo = int`.
609   if (Record.Type.isSimple())
610     return llvm::None;
611 
612   CVType cvt = tpi.getType(Record.Type);
613 
614   if (!IsTagRecord(cvt))
615     return llvm::None;
616 
617   // If it's an inner definition, then treat whatever name we have here as a
618   // single component of a mangled name.  So we can inject it into the parent's
619   // mangled name to see if it matches.
620   CVTagRecord child = CVTagRecord::create(cvt);
621   std::string qname = parent.asTag().getUniqueName();
622   if (qname.size() < 4 || child.asTag().getUniqueName().size() < 4)
623     return llvm::None;
624 
625   // qname[3] is the tag type identifier (struct, class, union, etc).  Since the
626   // inner tag type is not necessarily the same as the outer tag type, re-write
627   // it to match the inner tag type.
628   qname[3] = child.asTag().getUniqueName()[3];
629   std::string piece = Record.Name;
630   piece.push_back('@');
631   qname.insert(4, std::move(piece));
632   if (qname != child.asTag().UniqueName)
633     return llvm::None;
634 
635   return std::move(child);
636 }
637 
638 void SymbolFileNativePDB::PreprocessTpiStream() {
639   LazyRandomTypeCollection &types = m_index->tpi().typeCollection();
640 
641   for (auto ti = types.getFirst(); ti; ti = types.getNext(*ti)) {
642     CVType type = types.getType(*ti);
643     if (!IsTagRecord(type))
644       continue;
645 
646     CVTagRecord tag = CVTagRecord::create(type);
647     // We're looking for LF_NESTTYPE records in the field list, so ignore
648     // forward references (no field list), and anything without a nested class
649     // (since there won't be any LF_NESTTYPE records).
650     if (tag.asTag().isForwardRef() || !tag.asTag().containsNestedClass())
651       continue;
652 
653     struct ProcessTpiStream : public TypeVisitorCallbacks {
654       ProcessTpiStream(PdbIndex &index, TypeIndex parent,
655                        const CVTagRecord &parent_cvt,
656                        llvm::DenseMap<TypeIndex, TypeIndex> &parents)
657           : index(index), parents(parents), parent(parent),
658             parent_cvt(parent_cvt) {}
659 
660       PdbIndex &index;
661       llvm::DenseMap<TypeIndex, TypeIndex> &parents;
662       TypeIndex parent;
663       const CVTagRecord &parent_cvt;
664 
665       llvm::Error visitKnownMember(CVMemberRecord &CVR,
666                                    NestedTypeRecord &Record) override {
667         llvm::Optional<CVTagRecord> tag =
668             GetNestedTagRecord(Record, parent_cvt, index.tpi());
669         if (!tag)
670           return llvm::ErrorSuccess();
671 
672         parents[Record.Type] = parent;
673         if (!tag->asTag().isForwardRef())
674           return llvm::ErrorSuccess();
675 
676         llvm::Expected<TypeIndex> full_decl =
677             index.tpi().findFullDeclForForwardRef(Record.Type);
678         if (!full_decl) {
679           llvm::consumeError(full_decl.takeError());
680           return llvm::ErrorSuccess();
681         }
682         parents[*full_decl] = parent;
683         return llvm::ErrorSuccess();
684       }
685     };
686 
687     CVType field_list = m_index->tpi().getType(tag.asTag().FieldList);
688     ProcessTpiStream process(*m_index, *ti, tag, m_parent_types);
689     llvm::Error error = visitMemberRecordStream(field_list.data(), process);
690     if (error)
691       llvm::consumeError(std::move(error));
692   }
693 }
694 
695 uint32_t SymbolFileNativePDB::GetNumCompileUnits() {
696   const DbiModuleList &modules = m_index->dbi().modules();
697   uint32_t count = modules.getModuleCount();
698   if (count == 0)
699     return count;
700 
701   // The linker can inject an additional "dummy" compilation unit into the
702   // PDB. Ignore this special compile unit for our purposes, if it is there.
703   // It is always the last one.
704   DbiModuleDescriptor last = modules.getModuleDescriptor(count - 1);
705   if (last.getModuleName() == "* Linker *")
706     --count;
707   return count;
708 }
709 
710 lldb::FunctionSP SymbolFileNativePDB::CreateFunction(PdbCompilandSymId func_id,
711                                                      const SymbolContext &sc) {
712   const CompilandIndexItem *cci =
713       m_index->compilands().GetCompiland(func_id.modi);
714   lldbassert(cci);
715   CVSymbol sym_record = cci->m_debug_stream.readSymbolAtOffset(func_id.offset);
716 
717   lldbassert(sym_record.kind() == S_LPROC32 || sym_record.kind() == S_GPROC32);
718   SegmentOffsetLength sol = GetSegmentOffsetAndLength(sym_record);
719 
720   auto file_vm_addr = m_index->MakeVirtualAddress(sol.so);
721   if (file_vm_addr == LLDB_INVALID_ADDRESS || file_vm_addr == 0)
722     return nullptr;
723 
724   AddressRange func_range(file_vm_addr, sol.length,
725                           sc.module_sp->GetSectionList());
726   if (!func_range.GetBaseAddress().IsValid())
727     return nullptr;
728 
729   Type *func_type = nullptr;
730 
731   // FIXME: Resolve types and mangled names.
732   PdbTypeSymId sig_id(TypeIndex::None(), false);
733   Mangled mangled(getSymbolName(sym_record));
734   FunctionSP func_sp = std::make_shared<Function>(
735       sc.comp_unit, toOpaqueUid(func_id), toOpaqueUid(sig_id), mangled,
736       func_type, func_range);
737 
738   sc.comp_unit->AddFunction(func_sp);
739   return func_sp;
740 }
741 
742 CompUnitSP
743 SymbolFileNativePDB::CreateCompileUnit(const CompilandIndexItem &cci) {
744   lldb::LanguageType lang =
745       cci.m_compile_opts ? TranslateLanguage(cci.m_compile_opts->getLanguage())
746                          : lldb::eLanguageTypeUnknown;
747 
748   LazyBool optimized = eLazyBoolNo;
749   if (cci.m_compile_opts && cci.m_compile_opts->hasOptimizations())
750     optimized = eLazyBoolYes;
751 
752   llvm::StringRef source_file_name =
753       m_index->compilands().GetMainSourceFile(cci);
754   FileSpec fs(source_file_name);
755 
756   CompUnitSP cu_sp =
757       std::make_shared<CompileUnit>(m_obj_file->GetModule(), nullptr, fs,
758                                     toOpaqueUid(cci.m_id), lang, optimized);
759 
760   m_obj_file->GetModule()->GetSymbolVendor()->SetCompileUnitAtIndex(
761       cci.m_id.modi, cu_sp);
762   return cu_sp;
763 }
764 
765 lldb::TypeSP SymbolFileNativePDB::CreateModifierType(PdbTypeSymId type_id,
766                                                      const ModifierRecord &mr) {
767   TpiStream &stream = m_index->tpi();
768 
769   TypeSP t = GetOrCreateType(mr.ModifiedType);
770   CompilerType ct = t->GetForwardCompilerType();
771   if ((mr.Modifiers & ModifierOptions::Const) != ModifierOptions::None)
772     ct = ct.AddConstModifier();
773   if ((mr.Modifiers & ModifierOptions::Volatile) != ModifierOptions::None)
774     ct = ct.AddVolatileModifier();
775   std::string name;
776   if (mr.ModifiedType.isSimple())
777     name = GetSimpleTypeName(mr.ModifiedType.getSimpleKind());
778   else
779     name = computeTypeName(stream.typeCollection(), mr.ModifiedType);
780   Declaration decl;
781   return std::make_shared<Type>(toOpaqueUid(type_id), m_clang->GetSymbolFile(),
782                                 ConstString(name), t->GetByteSize(), nullptr,
783                                 LLDB_INVALID_UID, Type::eEncodingIsUID, decl,
784                                 ct, Type::eResolveStateFull);
785 }
786 
787 lldb::TypeSP SymbolFileNativePDB::CreatePointerType(
788     PdbTypeSymId type_id, const llvm::codeview::PointerRecord &pr) {
789   TypeSP pointee = GetOrCreateType(pr.ReferentType);
790   if (!pointee)
791     return nullptr;
792   CompilerType pointee_ct = pointee->GetForwardCompilerType();
793   lldbassert(pointee_ct);
794   Declaration decl;
795 
796   if (pr.isPointerToMember()) {
797     MemberPointerInfo mpi = pr.getMemberInfo();
798     TypeSP class_type = GetOrCreateType(mpi.ContainingType);
799 
800     CompilerType ct = ClangASTContext::CreateMemberPointerType(
801         class_type->GetLayoutCompilerType(), pointee_ct);
802 
803     return std::make_shared<Type>(
804         toOpaqueUid(type_id), m_clang->GetSymbolFile(), ConstString(),
805         pr.getSize(), nullptr, LLDB_INVALID_UID, Type::eEncodingIsUID, decl, ct,
806         Type::eResolveStateFull);
807   }
808 
809   CompilerType pointer_ct = pointee_ct;
810   if (pr.getMode() == PointerMode::LValueReference)
811     pointer_ct = pointer_ct.GetLValueReferenceType();
812   else if (pr.getMode() == PointerMode::RValueReference)
813     pointer_ct = pointer_ct.GetRValueReferenceType();
814   else
815     pointer_ct = pointer_ct.GetPointerType();
816 
817   if ((pr.getOptions() & PointerOptions::Const) != PointerOptions::None)
818     pointer_ct = pointer_ct.AddConstModifier();
819 
820   if ((pr.getOptions() & PointerOptions::Volatile) != PointerOptions::None)
821     pointer_ct = pointer_ct.AddVolatileModifier();
822 
823   if ((pr.getOptions() & PointerOptions::Restrict) != PointerOptions::None)
824     pointer_ct = pointer_ct.AddRestrictModifier();
825 
826   return std::make_shared<Type>(toOpaqueUid(type_id), m_clang->GetSymbolFile(),
827                                 ConstString(), pr.getSize(), nullptr,
828                                 LLDB_INVALID_UID, Type::eEncodingIsUID, decl,
829                                 pointer_ct, Type::eResolveStateFull);
830 }
831 
832 lldb::TypeSP SymbolFileNativePDB::CreateSimpleType(TypeIndex ti) {
833   uint64_t uid = toOpaqueUid(PdbTypeSymId(ti, false));
834   if (ti == TypeIndex::NullptrT()) {
835     CompilerType ct = m_clang->GetBasicType(eBasicTypeNullPtr);
836     Declaration decl;
837     return std::make_shared<Type>(
838         uid, this, ConstString("std::nullptr_t"), 0, nullptr, LLDB_INVALID_UID,
839         Type::eEncodingIsUID, decl, ct, Type::eResolveStateFull);
840   }
841 
842   if (ti.getSimpleMode() != SimpleTypeMode::Direct) {
843     TypeSP direct_sp = GetOrCreateType(ti.makeDirect());
844     CompilerType ct = direct_sp->GetFullCompilerType();
845     ct = ct.GetPointerType();
846     uint32_t pointer_size = 0;
847     switch (ti.getSimpleMode()) {
848     case SimpleTypeMode::FarPointer32:
849     case SimpleTypeMode::NearPointer32:
850       pointer_size = 4;
851       break;
852     case SimpleTypeMode::NearPointer64:
853       pointer_size = 8;
854       break;
855     default:
856       // 128-bit and 16-bit pointers unsupported.
857       return nullptr;
858     }
859     Declaration decl;
860     return std::make_shared<Type>(uid, m_clang->GetSymbolFile(), ConstString(),
861                                   pointer_size, nullptr, LLDB_INVALID_UID,
862                                   Type::eEncodingIsUID, decl, ct,
863                                   Type::eResolveStateFull);
864   }
865 
866   if (ti.getSimpleKind() == SimpleTypeKind::NotTranslated)
867     return nullptr;
868 
869   lldb::BasicType bt = GetCompilerTypeForSimpleKind(ti.getSimpleKind());
870   if (bt == lldb::eBasicTypeInvalid)
871     return nullptr;
872   CompilerType ct = m_clang->GetBasicType(bt);
873   size_t size = GetTypeSizeForSimpleKind(ti.getSimpleKind());
874 
875   llvm::StringRef type_name = GetSimpleTypeName(ti.getSimpleKind());
876 
877   Declaration decl;
878   return std::make_shared<Type>(uid, m_clang->GetSymbolFile(),
879                                 ConstString(type_name), size, nullptr,
880                                 LLDB_INVALID_UID, Type::eEncodingIsUID, decl,
881                                 ct, Type::eResolveStateFull);
882 }
883 
884 static std::string RenderDemanglerNode(llvm::ms_demangle::Node *n) {
885   OutputStream OS;
886   initializeOutputStream(nullptr, nullptr, OS, 1024);
887   n->output(OS, llvm::ms_demangle::OF_Default);
888   OS << '\0';
889   return {OS.getBuffer()};
890 }
891 
892 static bool
893 AnyScopesHaveTemplateParams(llvm::ArrayRef<llvm::ms_demangle::Node *> scopes) {
894   for (llvm::ms_demangle::Node *n : scopes) {
895     auto *idn = static_cast<llvm::ms_demangle::IdentifierNode *>(n);
896     if (idn->TemplateParams)
897       return true;
898   }
899   return false;
900 }
901 
902 std::pair<clang::DeclContext *, std::string>
903 SymbolFileNativePDB::CreateDeclInfoForType(const TagRecord &record,
904                                            TypeIndex ti) {
905   llvm::ms_demangle::Demangler demangler;
906   StringView sv(record.UniqueName.begin(), record.UniqueName.size());
907   llvm::ms_demangle::TagTypeNode *ttn = demangler.parseTagUniqueName(sv);
908   llvm::ms_demangle::IdentifierNode *idn =
909       ttn->QualifiedName->getUnqualifiedIdentifier();
910   std::string uname = RenderDemanglerNode(idn);
911 
912   llvm::ms_demangle::NodeArrayNode *name_components =
913       ttn->QualifiedName->Components;
914   llvm::ArrayRef<llvm::ms_demangle::Node *> scopes(name_components->Nodes,
915                                                    name_components->Count - 1);
916 
917   clang::DeclContext *context = m_clang->GetTranslationUnitDecl();
918 
919   // If this type doesn't have a parent type in the debug info, then the best we
920   // can do is to say that it's either a series of namespaces (if the scope is
921   // non-empty), or the translation unit (if the scope is empty).
922   auto parent_iter = m_parent_types.find(ti);
923   if (parent_iter == m_parent_types.end()) {
924     if (scopes.empty())
925       return {context, uname};
926 
927     // If there is no parent in the debug info, but some of the scopes have
928     // template params, then this is a case of bad debug info.  See, for
929     // example, llvm.org/pr39607.  We don't want to create an ambiguity between
930     // a NamespaceDecl and a CXXRecordDecl, so instead we create a class at
931     // global scope with the fully qualified name.
932     if (AnyScopesHaveTemplateParams(scopes))
933       return {context, record.Name};
934 
935     for (llvm::ms_demangle::Node *scope : scopes) {
936       auto *nii = static_cast<llvm::ms_demangle::NamedIdentifierNode *>(scope);
937       std::string str = RenderDemanglerNode(nii);
938       context = m_clang->GetUniqueNamespaceDeclaration(str.c_str(), context);
939     }
940     return {context, uname};
941   }
942 
943   // Otherwise, all we need to do is get the parent type of this type and
944   // recurse into our lazy type creation / AST reconstruction logic to get an
945   // LLDB TypeSP for the parent.  This will cause the AST to automatically get
946   // the right DeclContext created for any parent.
947   TypeSP parent = GetOrCreateType(parent_iter->second);
948   if (!parent)
949     return {context, uname};
950   CompilerType parent_ct = parent->GetForwardCompilerType();
951   clang::QualType qt = ClangUtil::GetCanonicalQualType(parent_ct);
952   context = clang::TagDecl::castToDeclContext(qt->getAsTagDecl());
953   return {context, uname};
954 }
955 
956 lldb::TypeSP SymbolFileNativePDB::CreateClassStructUnion(
957     PdbTypeSymId type_id, const llvm::codeview::TagRecord &record, size_t size,
958     clang::TagTypeKind ttk, clang::MSInheritanceAttr::Spelling inheritance) {
959 
960   clang::DeclContext *decl_context = nullptr;
961   std::string uname;
962   std::tie(decl_context, uname) = CreateDeclInfoForType(record, type_id.index);
963 
964   lldb::AccessType access =
965       (ttk == clang::TTK_Class) ? lldb::eAccessPrivate : lldb::eAccessPublic;
966 
967   ClangASTMetadata metadata;
968   metadata.SetUserID(toOpaqueUid(type_id));
969   metadata.SetIsDynamicCXXType(false);
970 
971   CompilerType ct =
972       m_clang->CreateRecordType(decl_context, access, uname.c_str(), ttk,
973                                 lldb::eLanguageTypeC_plus_plus, &metadata);
974 
975   lldbassert(ct.IsValid());
976 
977   clang::CXXRecordDecl *record_decl =
978       m_clang->GetAsCXXRecordDecl(ct.GetOpaqueQualType());
979   lldbassert(record_decl);
980 
981   clang::MSInheritanceAttr *attr = clang::MSInheritanceAttr::CreateImplicit(
982       *m_clang->getASTContext(), inheritance);
983   record_decl->addAttr(attr);
984 
985   ClangASTContext::StartTagDeclarationDefinition(ct);
986 
987   // Even if it's possible, don't complete it at this point. Just mark it
988   // forward resolved, and if/when LLDB needs the full definition, it can
989   // ask us.
990   ClangASTContext::SetHasExternalStorage(ct.GetOpaqueQualType(), true);
991 
992   // FIXME: Search IPI stream for LF_UDT_MOD_SRC_LINE.
993   Declaration decl;
994   return std::make_shared<Type>(toOpaqueUid(type_id), m_clang->GetSymbolFile(),
995                                 ConstString(uname), size, nullptr,
996                                 LLDB_INVALID_UID, Type::eEncodingIsUID, decl,
997                                 ct, Type::eResolveStateForward);
998 }
999 
1000 lldb::TypeSP SymbolFileNativePDB::CreateTagType(PdbTypeSymId type_id,
1001                                                 const ClassRecord &cr) {
1002   clang::TagTypeKind ttk = TranslateUdtKind(cr);
1003 
1004   clang::MSInheritanceAttr::Spelling inheritance =
1005       GetMSInheritance(m_index->tpi().typeCollection(), cr);
1006   return CreateClassStructUnion(type_id, cr, cr.getSize(), ttk, inheritance);
1007 }
1008 
1009 lldb::TypeSP SymbolFileNativePDB::CreateTagType(PdbTypeSymId type_id,
1010                                                 const UnionRecord &ur) {
1011   return CreateClassStructUnion(
1012       type_id, ur, ur.getSize(), clang::TTK_Union,
1013       clang::MSInheritanceAttr::Spelling::Keyword_single_inheritance);
1014 }
1015 
1016 lldb::TypeSP SymbolFileNativePDB::CreateTagType(PdbTypeSymId type_id,
1017                                                 const EnumRecord &er) {
1018   clang::DeclContext *decl_context = nullptr;
1019   std::string uname;
1020   std::tie(decl_context, uname) = CreateDeclInfoForType(er, type_id.index);
1021 
1022   Declaration decl;
1023   TypeSP underlying_type = GetOrCreateType(er.UnderlyingType);
1024   CompilerType enum_ct = m_clang->CreateEnumerationType(
1025       uname.c_str(), decl_context, decl, underlying_type->GetFullCompilerType(),
1026       er.isScoped());
1027 
1028   ClangASTContext::StartTagDeclarationDefinition(enum_ct);
1029   ClangASTContext::SetHasExternalStorage(enum_ct.GetOpaqueQualType(), true);
1030 
1031   // We're just going to forward resolve this for now.  We'll complete
1032   // it only if the user requests.
1033   return std::make_shared<lldb_private::Type>(
1034       toOpaqueUid(type_id), m_clang->GetSymbolFile(), ConstString(uname),
1035       underlying_type->GetByteSize(), nullptr, LLDB_INVALID_UID,
1036       lldb_private::Type::eEncodingIsUID, decl, enum_ct,
1037       lldb_private::Type::eResolveStateForward);
1038 }
1039 
1040 TypeSP SymbolFileNativePDB::CreateArrayType(PdbTypeSymId type_id,
1041                                             const ArrayRecord &ar) {
1042   TypeSP element_type = GetOrCreateType(ar.ElementType);
1043   uint64_t element_count = ar.Size / element_type->GetByteSize();
1044 
1045   CompilerType element_ct = element_type->GetFullCompilerType();
1046 
1047   CompilerType array_ct =
1048       m_clang->CreateArrayType(element_ct, element_count, false);
1049 
1050   Declaration decl;
1051   TypeSP array_sp = std::make_shared<lldb_private::Type>(
1052       toOpaqueUid(type_id), m_clang->GetSymbolFile(), ConstString(), ar.Size,
1053       nullptr, LLDB_INVALID_UID, lldb_private::Type::eEncodingIsUID, decl,
1054       array_ct, lldb_private::Type::eResolveStateFull);
1055   array_sp->SetEncodingType(element_type.get());
1056   return array_sp;
1057 }
1058 
1059 TypeSP SymbolFileNativePDB::CreateProcedureType(PdbTypeSymId type_id,
1060                                                 const ProcedureRecord &pr) {
1061   TpiStream &stream = m_index->tpi();
1062   CVType args_cvt = stream.getType(pr.ArgumentList);
1063   ArgListRecord args;
1064   llvm::cantFail(
1065       TypeDeserializer::deserializeAs<ArgListRecord>(args_cvt, args));
1066 
1067   llvm::ArrayRef<TypeIndex> arg_indices = llvm::makeArrayRef(args.ArgIndices);
1068   bool is_variadic = IsCVarArgsFunction(arg_indices);
1069   if (is_variadic)
1070     arg_indices = arg_indices.drop_back();
1071 
1072   std::vector<CompilerType> arg_list;
1073   arg_list.reserve(arg_list.size());
1074 
1075   for (TypeIndex arg_index : arg_indices) {
1076     TypeSP arg_sp = GetOrCreateType(arg_index);
1077     if (!arg_sp)
1078       return nullptr;
1079     arg_list.push_back(arg_sp->GetFullCompilerType());
1080   }
1081 
1082   TypeSP return_type_sp = GetOrCreateType(pr.ReturnType);
1083   if (!return_type_sp)
1084     return nullptr;
1085 
1086   llvm::Optional<clang::CallingConv> cc =
1087       TranslateCallingConvention(pr.CallConv);
1088   if (!cc)
1089     return nullptr;
1090 
1091   CompilerType return_ct = return_type_sp->GetFullCompilerType();
1092   CompilerType func_sig_ast_type = m_clang->CreateFunctionType(
1093       return_ct, arg_list.data(), arg_list.size(), is_variadic, 0, *cc);
1094 
1095   Declaration decl;
1096   return std::make_shared<lldb_private::Type>(
1097       toOpaqueUid(type_id), this, ConstString(), 0, nullptr, LLDB_INVALID_UID,
1098       lldb_private::Type::eEncodingIsUID, decl, func_sig_ast_type,
1099       lldb_private::Type::eResolveStateFull);
1100 }
1101 
1102 TypeSP SymbolFileNativePDB::CreateType(PdbTypeSymId type_id) {
1103   if (type_id.index.isSimple())
1104     return CreateSimpleType(type_id.index);
1105 
1106   TpiStream &stream = type_id.is_ipi ? m_index->ipi() : m_index->tpi();
1107   CVType cvt = stream.getType(type_id.index);
1108 
1109   if (cvt.kind() == LF_MODIFIER) {
1110     ModifierRecord modifier;
1111     llvm::cantFail(
1112         TypeDeserializer::deserializeAs<ModifierRecord>(cvt, modifier));
1113     return CreateModifierType(type_id, modifier);
1114   }
1115 
1116   if (cvt.kind() == LF_POINTER) {
1117     PointerRecord pointer;
1118     llvm::cantFail(
1119         TypeDeserializer::deserializeAs<PointerRecord>(cvt, pointer));
1120     return CreatePointerType(type_id, pointer);
1121   }
1122 
1123   if (IsClassRecord(cvt.kind())) {
1124     ClassRecord cr;
1125     llvm::cantFail(TypeDeserializer::deserializeAs<ClassRecord>(cvt, cr));
1126     return CreateTagType(type_id, cr);
1127   }
1128 
1129   if (cvt.kind() == LF_ENUM) {
1130     EnumRecord er;
1131     llvm::cantFail(TypeDeserializer::deserializeAs<EnumRecord>(cvt, er));
1132     return CreateTagType(type_id, er);
1133   }
1134 
1135   if (cvt.kind() == LF_UNION) {
1136     UnionRecord ur;
1137     llvm::cantFail(TypeDeserializer::deserializeAs<UnionRecord>(cvt, ur));
1138     return CreateTagType(type_id, ur);
1139   }
1140 
1141   if (cvt.kind() == LF_ARRAY) {
1142     ArrayRecord ar;
1143     llvm::cantFail(TypeDeserializer::deserializeAs<ArrayRecord>(cvt, ar));
1144     return CreateArrayType(type_id, ar);
1145   }
1146 
1147   if (cvt.kind() == LF_PROCEDURE) {
1148     ProcedureRecord pr;
1149     llvm::cantFail(TypeDeserializer::deserializeAs<ProcedureRecord>(cvt, pr));
1150     return CreateProcedureType(type_id, pr);
1151   }
1152 
1153   return nullptr;
1154 }
1155 
1156 TypeSP SymbolFileNativePDB::CreateAndCacheType(PdbTypeSymId type_id) {
1157   // If they search for a UDT which is a forward ref, try and resolve the full
1158   // decl and just map the forward ref uid to the full decl record.
1159   llvm::Optional<PdbTypeSymId> full_decl_uid;
1160   if (IsForwardRefUdt(type_id, m_index->tpi())) {
1161     auto expected_full_ti =
1162         m_index->tpi().findFullDeclForForwardRef(type_id.index);
1163     if (!expected_full_ti)
1164       llvm::consumeError(expected_full_ti.takeError());
1165     else if (*expected_full_ti != type_id.index) {
1166       full_decl_uid = PdbTypeSymId(*expected_full_ti, false);
1167 
1168       // It's possible that a lookup would occur for the full decl causing it
1169       // to be cached, then a second lookup would occur for the forward decl.
1170       // We don't want to create a second full decl, so make sure the full
1171       // decl hasn't already been cached.
1172       auto full_iter = m_types.find(toOpaqueUid(*full_decl_uid));
1173       if (full_iter != m_types.end()) {
1174         TypeSP result = full_iter->second;
1175         // Map the forward decl to the TypeSP for the full decl so we can take
1176         // the fast path next time.
1177         m_types[toOpaqueUid(type_id)] = result;
1178         return result;
1179       }
1180     }
1181   }
1182 
1183   PdbTypeSymId best_decl_id = full_decl_uid ? *full_decl_uid : type_id;
1184   TypeSP result = CreateType(best_decl_id);
1185   if (!result)
1186     return nullptr;
1187 
1188   uint64_t best_uid = toOpaqueUid(best_decl_id);
1189   m_types[best_uid] = result;
1190   // If we had both a forward decl and a full decl, make both point to the new
1191   // type.
1192   if (full_decl_uid)
1193     m_types[toOpaqueUid(type_id)] = result;
1194 
1195   if (IsTagRecord(best_decl_id, m_index->tpi())) {
1196     clang::TagDecl *record_decl =
1197         m_clang->GetAsTagDecl(result->GetForwardCompilerType());
1198     lldbassert(record_decl);
1199 
1200     m_uid_to_decl[best_uid] = record_decl;
1201     m_decl_to_status[record_decl] =
1202         DeclStatus(best_uid, Type::eResolveStateForward);
1203   }
1204   return result;
1205 }
1206 
1207 TypeSP SymbolFileNativePDB::GetOrCreateType(PdbTypeSymId type_id) {
1208   // We can't use try_emplace / overwrite here because the process of creating
1209   // a type could create nested types, which could invalidate iterators.  So
1210   // we have to do a 2-phase lookup / insert.
1211   auto iter = m_types.find(toOpaqueUid(type_id));
1212   if (iter != m_types.end())
1213     return iter->second;
1214 
1215   return CreateAndCacheType(type_id);
1216 }
1217 
1218 static DWARFExpression
1219 MakeConstantLocationExpression(TypeIndex underlying_ti, TpiStream &tpi,
1220                                const ConstantSym &constant, ModuleSP module) {
1221   const ArchSpec &architecture = module->GetArchitecture();
1222   uint32_t address_size = architecture.GetAddressByteSize();
1223 
1224   size_t size = 0;
1225   bool is_signed = false;
1226   std::tie(size, is_signed) = GetIntegralTypeInfo(underlying_ti, tpi);
1227 
1228   union {
1229     llvm::support::little64_t I;
1230     llvm::support::ulittle64_t U;
1231   } Value;
1232 
1233   std::shared_ptr<DataBufferHeap> buffer = std::make_shared<DataBufferHeap>();
1234   buffer->SetByteSize(size);
1235 
1236   llvm::ArrayRef<uint8_t> bytes;
1237   if (is_signed) {
1238     Value.I = constant.Value.getSExtValue();
1239   } else {
1240     Value.U = constant.Value.getZExtValue();
1241   }
1242 
1243   bytes = llvm::makeArrayRef(reinterpret_cast<const uint8_t *>(&Value), 8)
1244               .take_front(size);
1245   buffer->CopyData(bytes.data(), size);
1246   DataExtractor extractor(buffer, lldb::eByteOrderLittle, address_size);
1247   DWARFExpression result(nullptr, extractor, nullptr, 0, size);
1248   return result;
1249 }
1250 
1251 static DWARFExpression MakeGlobalLocationExpression(uint16_t section,
1252                                                     uint32_t offset,
1253                                                     ModuleSP module) {
1254   assert(section > 0);
1255   assert(module);
1256 
1257   const ArchSpec &architecture = module->GetArchitecture();
1258   ByteOrder byte_order = architecture.GetByteOrder();
1259   uint32_t address_size = architecture.GetAddressByteSize();
1260   uint32_t byte_size = architecture.GetDataByteSize();
1261   assert(byte_order != eByteOrderInvalid && address_size != 0);
1262 
1263   RegisterKind register_kind = eRegisterKindDWARF;
1264   StreamBuffer<32> stream(Stream::eBinary, address_size, byte_order);
1265   stream.PutHex8(DW_OP_addr);
1266 
1267   SectionList *section_list = module->GetSectionList();
1268   assert(section_list);
1269 
1270   // Section indices in PDB are 1-based, but in DWARF they are 0-based, so we
1271   // need to subtract 1.
1272   uint32_t section_idx = section - 1;
1273   if (section_idx >= section_list->GetSize())
1274     return DWARFExpression(nullptr);
1275 
1276   auto section_ptr = section_list->GetSectionAtIndex(section_idx);
1277   if (!section_ptr)
1278     return DWARFExpression(nullptr);
1279 
1280   stream.PutMaxHex64(section_ptr->GetFileAddress() + offset, address_size,
1281                      byte_order);
1282   DataBufferSP buffer =
1283       std::make_shared<DataBufferHeap>(stream.GetData(), stream.GetSize());
1284   DataExtractor extractor(buffer, byte_order, address_size, byte_size);
1285   DWARFExpression result(module, extractor, nullptr, 0, buffer->GetByteSize());
1286   result.SetRegisterKind(register_kind);
1287   return result;
1288 }
1289 
1290 VariableSP SymbolFileNativePDB::CreateGlobalVariable(PdbGlobalSymId var_id) {
1291   CVSymbol sym = m_index->symrecords().readRecord(var_id.offset);
1292   if (sym.kind() == S_CONSTANT)
1293     return CreateConstantSymbol(var_id, sym);
1294 
1295   lldb::ValueType scope = eValueTypeInvalid;
1296   TypeIndex ti;
1297   llvm::StringRef name;
1298   lldb::addr_t addr = 0;
1299   uint16_t section = 0;
1300   uint32_t offset = 0;
1301   bool is_external = false;
1302   switch (sym.kind()) {
1303   case S_GDATA32:
1304     is_external = true;
1305     LLVM_FALLTHROUGH;
1306   case S_LDATA32: {
1307     DataSym ds(sym.kind());
1308     llvm::cantFail(SymbolDeserializer::deserializeAs<DataSym>(sym, ds));
1309     ti = ds.Type;
1310     scope = (sym.kind() == S_GDATA32) ? eValueTypeVariableGlobal
1311                                       : eValueTypeVariableStatic;
1312     name = ds.Name;
1313     section = ds.Segment;
1314     offset = ds.DataOffset;
1315     addr = m_index->MakeVirtualAddress(ds.Segment, ds.DataOffset);
1316     break;
1317   }
1318   case S_GTHREAD32:
1319     is_external = true;
1320     LLVM_FALLTHROUGH;
1321   case S_LTHREAD32: {
1322     ThreadLocalDataSym tlds(sym.kind());
1323     llvm::cantFail(
1324         SymbolDeserializer::deserializeAs<ThreadLocalDataSym>(sym, tlds));
1325     ti = tlds.Type;
1326     name = tlds.Name;
1327     section = tlds.Segment;
1328     offset = tlds.DataOffset;
1329     addr = m_index->MakeVirtualAddress(tlds.Segment, tlds.DataOffset);
1330     scope = eValueTypeVariableThreadLocal;
1331     break;
1332   }
1333   default:
1334     llvm_unreachable("unreachable!");
1335   }
1336 
1337   CompUnitSP comp_unit;
1338   llvm::Optional<uint16_t> modi = m_index->GetModuleIndexForVa(addr);
1339   if (modi) {
1340     CompilandIndexItem &cci = m_index->compilands().GetOrCreateCompiland(*modi);
1341     comp_unit = GetOrCreateCompileUnit(cci);
1342   }
1343 
1344   Declaration decl;
1345   PdbTypeSymId tid(ti, false);
1346   SymbolFileTypeSP type_sp =
1347       std::make_shared<SymbolFileType>(*this, toOpaqueUid(tid));
1348   Variable::RangeList ranges;
1349 
1350   DWARFExpression location = MakeGlobalLocationExpression(
1351       section, offset, GetObjectFile()->GetModule());
1352 
1353   std::string global_name("::");
1354   global_name += name;
1355   VariableSP var_sp = std::make_shared<Variable>(
1356       toOpaqueUid(var_id), name.str().c_str(), global_name.c_str(), type_sp,
1357       scope, comp_unit.get(), ranges, &decl, location, is_external, false,
1358       false);
1359   var_sp->SetLocationIsConstantValueData(false);
1360 
1361   return var_sp;
1362 }
1363 
1364 lldb::VariableSP
1365 SymbolFileNativePDB::CreateConstantSymbol(PdbGlobalSymId var_id,
1366                                           const CVSymbol &cvs) {
1367   TpiStream &tpi = m_index->tpi();
1368   ConstantSym constant(cvs.kind());
1369 
1370   llvm::cantFail(SymbolDeserializer::deserializeAs<ConstantSym>(cvs, constant));
1371   std::string global_name("::");
1372   global_name += constant.Name;
1373   PdbTypeSymId tid(constant.Type, false);
1374   SymbolFileTypeSP type_sp =
1375       std::make_shared<SymbolFileType>(*this, toOpaqueUid(tid));
1376 
1377   Declaration decl;
1378   Variable::RangeList ranges;
1379   ModuleSP module = GetObjectFile()->GetModule();
1380   DWARFExpression location =
1381       MakeConstantLocationExpression(constant.Type, tpi, constant, module);
1382 
1383   VariableSP var_sp = std::make_shared<Variable>(
1384       toOpaqueUid(var_id), constant.Name.str().c_str(), global_name.c_str(),
1385       type_sp, eValueTypeVariableGlobal, module.get(), ranges, &decl, location,
1386       false, false, false);
1387   var_sp->SetLocationIsConstantValueData(true);
1388   return var_sp;
1389 }
1390 
1391 VariableSP
1392 SymbolFileNativePDB::GetOrCreateGlobalVariable(PdbGlobalSymId var_id) {
1393   auto emplace_result = m_global_vars.try_emplace(toOpaqueUid(var_id), nullptr);
1394   if (emplace_result.second)
1395     emplace_result.first->second = CreateGlobalVariable(var_id);
1396 
1397   return emplace_result.first->second;
1398 }
1399 
1400 lldb::TypeSP SymbolFileNativePDB::GetOrCreateType(TypeIndex ti) {
1401   return GetOrCreateType(PdbTypeSymId(ti, false));
1402 }
1403 
1404 FunctionSP SymbolFileNativePDB::GetOrCreateFunction(PdbCompilandSymId func_id,
1405                                                     const SymbolContext &sc) {
1406   auto emplace_result = m_functions.try_emplace(toOpaqueUid(func_id), nullptr);
1407   if (emplace_result.second)
1408     emplace_result.first->second = CreateFunction(func_id, sc);
1409 
1410   lldbassert(emplace_result.first->second);
1411   return emplace_result.first->second;
1412 }
1413 
1414 CompUnitSP
1415 SymbolFileNativePDB::GetOrCreateCompileUnit(const CompilandIndexItem &cci) {
1416 
1417   auto emplace_result =
1418       m_compilands.try_emplace(toOpaqueUid(cci.m_id), nullptr);
1419   if (emplace_result.second)
1420     emplace_result.first->second = CreateCompileUnit(cci);
1421 
1422   lldbassert(emplace_result.first->second);
1423   return emplace_result.first->second;
1424 }
1425 
1426 lldb::CompUnitSP SymbolFileNativePDB::ParseCompileUnitAtIndex(uint32_t index) {
1427   if (index >= GetNumCompileUnits())
1428     return CompUnitSP();
1429   lldbassert(index < UINT16_MAX);
1430   if (index >= UINT16_MAX)
1431     return nullptr;
1432 
1433   CompilandIndexItem &item = m_index->compilands().GetOrCreateCompiland(index);
1434 
1435   return GetOrCreateCompileUnit(item);
1436 }
1437 
1438 lldb::LanguageType
1439 SymbolFileNativePDB::ParseCompileUnitLanguage(const SymbolContext &sc) {
1440   // What fields should I expect to be filled out on the SymbolContext?  Is it
1441   // safe to assume that `sc.comp_unit` is valid?
1442   if (!sc.comp_unit)
1443     return lldb::eLanguageTypeUnknown;
1444   PdbSymUid uid(sc.comp_unit->GetID());
1445   lldbassert(uid.kind() == PdbSymUidKind::Compiland);
1446 
1447   CompilandIndexItem *item =
1448       m_index->compilands().GetCompiland(uid.asCompiland().modi);
1449   lldbassert(item);
1450   if (!item->m_compile_opts)
1451     return lldb::eLanguageTypeUnknown;
1452 
1453   return TranslateLanguage(item->m_compile_opts->getLanguage());
1454 }
1455 
1456 size_t SymbolFileNativePDB::ParseCompileUnitFunctions(const SymbolContext &sc) {
1457   lldbassert(sc.comp_unit);
1458   return false;
1459 }
1460 
1461 static bool NeedsResolvedCompileUnit(uint32_t resolve_scope) {
1462   // If any of these flags are set, we need to resolve the compile unit.
1463   uint32_t flags = eSymbolContextCompUnit;
1464   flags |= eSymbolContextVariable;
1465   flags |= eSymbolContextFunction;
1466   flags |= eSymbolContextBlock;
1467   flags |= eSymbolContextLineEntry;
1468   return (resolve_scope & flags) != 0;
1469 }
1470 
1471 uint32_t SymbolFileNativePDB::ResolveSymbolContext(
1472     const Address &addr, SymbolContextItem resolve_scope, SymbolContext &sc) {
1473   uint32_t resolved_flags = 0;
1474   lldb::addr_t file_addr = addr.GetFileAddress();
1475 
1476   if (NeedsResolvedCompileUnit(resolve_scope)) {
1477     llvm::Optional<uint16_t> modi = m_index->GetModuleIndexForVa(file_addr);
1478     if (!modi)
1479       return 0;
1480     CompilandIndexItem *cci = m_index->compilands().GetCompiland(*modi);
1481     if (!cci)
1482       return 0;
1483 
1484     sc.comp_unit = GetOrCreateCompileUnit(*cci).get();
1485     resolved_flags |= eSymbolContextCompUnit;
1486   }
1487 
1488   if (resolve_scope & eSymbolContextFunction) {
1489     lldbassert(sc.comp_unit);
1490     std::vector<SymbolAndUid> matches = m_index->FindSymbolsByVa(file_addr);
1491     for (const auto &match : matches) {
1492       if (match.uid.kind() != PdbSymUidKind::CompilandSym)
1493         continue;
1494       PdbCompilandSymId csid = match.uid.asCompilandSym();
1495       CVSymbol cvs = m_index->ReadSymbolRecord(csid);
1496       if (CVSymToPDBSym(cvs.kind()) != PDB_SymType::Function)
1497         continue;
1498       sc.function = GetOrCreateFunction(csid, sc).get();
1499     }
1500     resolved_flags |= eSymbolContextFunction;
1501   }
1502 
1503   if (resolve_scope & eSymbolContextLineEntry) {
1504     lldbassert(sc.comp_unit);
1505     if (auto *line_table = sc.comp_unit->GetLineTable()) {
1506       if (line_table->FindLineEntryByAddress(addr, sc.line_entry))
1507         resolved_flags |= eSymbolContextLineEntry;
1508     }
1509   }
1510 
1511   return resolved_flags;
1512 }
1513 
1514 static void AppendLineEntryToSequence(LineTable &table, LineSequence &sequence,
1515                                       const CompilandIndexItem &cci,
1516                                       lldb::addr_t base_addr,
1517                                       uint32_t file_number,
1518                                       const LineFragmentHeader &block,
1519                                       const LineNumberEntry &cur) {
1520   LineInfo cur_info(cur.Flags);
1521 
1522   if (cur_info.isAlwaysStepInto() || cur_info.isNeverStepInto())
1523     return;
1524 
1525   uint64_t addr = base_addr + cur.Offset;
1526 
1527   bool is_statement = cur_info.isStatement();
1528   bool is_prologue = IsFunctionPrologue(cci, addr);
1529   bool is_epilogue = IsFunctionEpilogue(cci, addr);
1530 
1531   uint32_t lno = cur_info.getStartLine();
1532 
1533   table.AppendLineEntryToSequence(&sequence, addr, lno, 0, file_number,
1534                                   is_statement, false, is_prologue, is_epilogue,
1535                                   false);
1536 }
1537 
1538 static void TerminateLineSequence(LineTable &table,
1539                                   const LineFragmentHeader &block,
1540                                   lldb::addr_t base_addr, uint32_t file_number,
1541                                   uint32_t last_line,
1542                                   std::unique_ptr<LineSequence> seq) {
1543   // The end is always a terminal entry, so insert it regardless.
1544   table.AppendLineEntryToSequence(seq.get(), base_addr + block.CodeSize,
1545                                   last_line, 0, file_number, false, false,
1546                                   false, false, true);
1547   table.InsertSequence(seq.release());
1548 }
1549 
1550 bool SymbolFileNativePDB::ParseCompileUnitLineTable(const SymbolContext &sc) {
1551   // Unfortunately LLDB is set up to parse the entire compile unit line table
1552   // all at once, even if all it really needs is line info for a specific
1553   // function.  In the future it would be nice if it could set the sc.m_function
1554   // member, and we could only get the line info for the function in question.
1555   lldbassert(sc.comp_unit);
1556   PdbSymUid cu_id(sc.comp_unit->GetID());
1557   lldbassert(cu_id.kind() == PdbSymUidKind::Compiland);
1558   CompilandIndexItem *cci =
1559       m_index->compilands().GetCompiland(cu_id.asCompiland().modi);
1560   lldbassert(cci);
1561   auto line_table = llvm::make_unique<LineTable>(sc.comp_unit);
1562 
1563   // This is basically a copy of the .debug$S subsections from all original COFF
1564   // object files merged together with address relocations applied.  We are
1565   // looking for all DEBUG_S_LINES subsections.
1566   for (const DebugSubsectionRecord &dssr :
1567        cci->m_debug_stream.getSubsectionsArray()) {
1568     if (dssr.kind() != DebugSubsectionKind::Lines)
1569       continue;
1570 
1571     DebugLinesSubsectionRef lines;
1572     llvm::BinaryStreamReader reader(dssr.getRecordData());
1573     if (auto EC = lines.initialize(reader)) {
1574       llvm::consumeError(std::move(EC));
1575       return false;
1576     }
1577 
1578     const LineFragmentHeader *lfh = lines.header();
1579     uint64_t virtual_addr =
1580         m_index->MakeVirtualAddress(lfh->RelocSegment, lfh->RelocOffset);
1581 
1582     const auto &checksums = cci->m_strings.checksums().getArray();
1583     const auto &strings = cci->m_strings.strings();
1584     for (const LineColumnEntry &group : lines) {
1585       // Indices in this structure are actually offsets of records in the
1586       // DEBUG_S_FILECHECKSUMS subsection.  Those entries then have an index
1587       // into the global PDB string table.
1588       auto iter = checksums.at(group.NameIndex);
1589       if (iter == checksums.end())
1590         continue;
1591 
1592       llvm::Expected<llvm::StringRef> efn =
1593           strings.getString(iter->FileNameOffset);
1594       if (!efn) {
1595         llvm::consumeError(efn.takeError());
1596         continue;
1597       }
1598 
1599       // LLDB wants the index of the file in the list of support files.
1600       auto fn_iter = llvm::find(cci->m_file_list, *efn);
1601       lldbassert(fn_iter != cci->m_file_list.end());
1602       uint32_t file_index = std::distance(cci->m_file_list.begin(), fn_iter);
1603 
1604       std::unique_ptr<LineSequence> sequence(
1605           line_table->CreateLineSequenceContainer());
1606       lldbassert(!group.LineNumbers.empty());
1607 
1608       for (const LineNumberEntry &entry : group.LineNumbers) {
1609         AppendLineEntryToSequence(*line_table, *sequence, *cci, virtual_addr,
1610                                   file_index, *lfh, entry);
1611       }
1612       LineInfo last_line(group.LineNumbers.back().Flags);
1613       TerminateLineSequence(*line_table, *lfh, virtual_addr, file_index,
1614                             last_line.getEndLine(), std::move(sequence));
1615     }
1616   }
1617 
1618   if (line_table->GetSize() == 0)
1619     return false;
1620 
1621   sc.comp_unit->SetLineTable(line_table.release());
1622   return true;
1623 }
1624 
1625 bool SymbolFileNativePDB::ParseCompileUnitDebugMacros(const SymbolContext &sc) {
1626   // PDB doesn't contain information about macros
1627   return false;
1628 }
1629 
1630 bool SymbolFileNativePDB::ParseCompileUnitSupportFiles(
1631     const SymbolContext &sc, FileSpecList &support_files) {
1632   lldbassert(sc.comp_unit);
1633 
1634   PdbSymUid cu_id(sc.comp_unit->GetID());
1635   lldbassert(cu_id.kind() == PdbSymUidKind::Compiland);
1636   CompilandIndexItem *cci =
1637       m_index->compilands().GetCompiland(cu_id.asCompiland().modi);
1638   lldbassert(cci);
1639 
1640   for (llvm::StringRef f : cci->m_file_list) {
1641     FileSpec::Style style =
1642         f.startswith("/") ? FileSpec::Style::posix : FileSpec::Style::windows;
1643     FileSpec spec(f, style);
1644     support_files.Append(spec);
1645   }
1646 
1647   return true;
1648 }
1649 
1650 bool SymbolFileNativePDB::ParseImportedModules(
1651     const SymbolContext &sc, std::vector<ConstString> &imported_modules) {
1652   // PDB does not yet support module debug info
1653   return false;
1654 }
1655 
1656 size_t SymbolFileNativePDB::ParseFunctionBlocks(const SymbolContext &sc) {
1657   lldbassert(sc.comp_unit && sc.function);
1658   return 0;
1659 }
1660 
1661 void SymbolFileNativePDB::DumpClangAST(Stream &s) {
1662   if (!m_clang)
1663     return;
1664   m_clang->Dump(s);
1665 }
1666 
1667 uint32_t SymbolFileNativePDB::FindGlobalVariables(
1668     const ConstString &name, const CompilerDeclContext *parent_decl_ctx,
1669     uint32_t max_matches, VariableList &variables) {
1670   using SymbolAndOffset = std::pair<uint32_t, llvm::codeview::CVSymbol>;
1671 
1672   std::vector<SymbolAndOffset> results = m_index->globals().findRecordsByName(
1673       name.GetStringRef(), m_index->symrecords());
1674   for (const SymbolAndOffset &result : results) {
1675     VariableSP var;
1676     switch (result.second.kind()) {
1677     case SymbolKind::S_GDATA32:
1678     case SymbolKind::S_LDATA32:
1679     case SymbolKind::S_GTHREAD32:
1680     case SymbolKind::S_LTHREAD32:
1681     case SymbolKind::S_CONSTANT: {
1682       PdbGlobalSymId global(result.first, false);
1683       var = GetOrCreateGlobalVariable(global);
1684       variables.AddVariable(var);
1685       break;
1686     }
1687     default:
1688       continue;
1689     }
1690   }
1691   return variables.GetSize();
1692 }
1693 
1694 uint32_t SymbolFileNativePDB::FindFunctions(
1695     const ConstString &name, const CompilerDeclContext *parent_decl_ctx,
1696     FunctionNameType name_type_mask, bool include_inlines, bool append,
1697     SymbolContextList &sc_list) {
1698   // For now we only support lookup by method name.
1699   if (!(name_type_mask & eFunctionNameTypeMethod))
1700     return 0;
1701 
1702   using SymbolAndOffset = std::pair<uint32_t, llvm::codeview::CVSymbol>;
1703 
1704   std::vector<SymbolAndOffset> matches = m_index->globals().findRecordsByName(
1705       name.GetStringRef(), m_index->symrecords());
1706   for (const SymbolAndOffset &match : matches) {
1707     if (match.second.kind() != S_PROCREF && match.second.kind() != S_LPROCREF)
1708       continue;
1709     ProcRefSym proc(match.second.kind());
1710     cantFail(SymbolDeserializer::deserializeAs<ProcRefSym>(match.second, proc));
1711 
1712     if (!IsValidRecord(proc))
1713       continue;
1714 
1715     CompilandIndexItem &cci =
1716         m_index->compilands().GetOrCreateCompiland(proc.modi());
1717     SymbolContext sc;
1718 
1719     sc.comp_unit = GetOrCreateCompileUnit(cci).get();
1720     sc.module_sp = sc.comp_unit->GetModule();
1721     PdbCompilandSymId func_id(proc.modi(), proc.SymOffset);
1722     sc.function = GetOrCreateFunction(func_id, sc).get();
1723 
1724     sc_list.Append(sc);
1725   }
1726 
1727   return sc_list.GetSize();
1728 }
1729 
1730 uint32_t SymbolFileNativePDB::FindFunctions(const RegularExpression &regex,
1731                                             bool include_inlines, bool append,
1732                                             SymbolContextList &sc_list) {
1733   return 0;
1734 }
1735 
1736 uint32_t SymbolFileNativePDB::FindTypes(
1737     const SymbolContext &sc, const ConstString &name,
1738     const CompilerDeclContext *parent_decl_ctx, bool append,
1739     uint32_t max_matches, llvm::DenseSet<SymbolFile *> &searched_symbol_files,
1740     TypeMap &types) {
1741   if (!append)
1742     types.Clear();
1743   if (!name)
1744     return 0;
1745 
1746   searched_symbol_files.clear();
1747   searched_symbol_files.insert(this);
1748 
1749   // There is an assumption 'name' is not a regex
1750   size_t match_count = FindTypesByName(name.GetStringRef(), max_matches, types);
1751 
1752   return match_count;
1753 }
1754 
1755 size_t
1756 SymbolFileNativePDB::FindTypes(const std::vector<CompilerContext> &context,
1757                                bool append, TypeMap &types) {
1758   return 0;
1759 }
1760 
1761 size_t SymbolFileNativePDB::FindTypesByName(llvm::StringRef name,
1762                                             uint32_t max_matches,
1763                                             TypeMap &types) {
1764 
1765   size_t match_count = 0;
1766   std::vector<TypeIndex> matches = m_index->tpi().findRecordsByName(name);
1767   if (max_matches > 0 && max_matches < matches.size())
1768     matches.resize(max_matches);
1769 
1770   for (TypeIndex ti : matches) {
1771     TypeSP type = GetOrCreateType(ti);
1772     if (!type)
1773       continue;
1774 
1775     types.Insert(type);
1776     ++match_count;
1777   }
1778   return match_count;
1779 }
1780 
1781 size_t SymbolFileNativePDB::ParseTypes(const SymbolContext &sc) { return 0; }
1782 
1783 Type *SymbolFileNativePDB::ResolveTypeUID(lldb::user_id_t type_uid) {
1784   auto iter = m_types.find(type_uid);
1785   // lldb should not be passing us non-sensical type uids.  the only way it
1786   // could have a type uid in the first place is if we handed it out, in which
1787   // case we should know about the type.  However, that doesn't mean we've
1788   // instantiated it yet.  We can vend out a UID for a future type.  So if the
1789   // type doesn't exist, let's instantiate it now.
1790   if (iter != m_types.end())
1791     return &*iter->second;
1792 
1793   PdbSymUid uid(type_uid);
1794   lldbassert(uid.kind() == PdbSymUidKind::Type);
1795   PdbTypeSymId type_id = uid.asTypeSym();
1796   if (type_id.index.isNoneType())
1797     return nullptr;
1798 
1799   TypeSP type_sp = CreateAndCacheType(type_id);
1800   return &*type_sp;
1801 }
1802 
1803 llvm::Optional<SymbolFile::ArrayInfo>
1804 SymbolFileNativePDB::GetDynamicArrayInfoForUID(
1805     lldb::user_id_t type_uid, const lldb_private::ExecutionContext *exe_ctx) {
1806   return llvm::None;
1807 }
1808 
1809 
1810 bool SymbolFileNativePDB::CompleteType(CompilerType &compiler_type) {
1811   // If this is not in our map, it's an error.
1812   clang::TagDecl *tag_decl = m_clang->GetAsTagDecl(compiler_type);
1813   lldbassert(tag_decl);
1814   auto status_iter = m_decl_to_status.find(tag_decl);
1815   lldbassert(status_iter != m_decl_to_status.end());
1816 
1817   // If it's already complete, just return.
1818   DeclStatus &status = status_iter->second;
1819   if (status.status == Type::eResolveStateFull)
1820     return true;
1821 
1822   PdbTypeSymId type_id = PdbSymUid(status.uid).asTypeSym();
1823 
1824   lldbassert(IsTagRecord(type_id, m_index->tpi()));
1825 
1826   ClangASTContext::SetHasExternalStorage(compiler_type.GetOpaqueQualType(),
1827                                          false);
1828 
1829   // In CreateAndCacheType, we already go out of our way to resolve forward
1830   // ref UDTs to full decls, and the uids we vend out always refer to full
1831   // decls if a full decl exists in the debug info.  So if we don't have a full
1832   // decl here, it means one doesn't exist in the debug info, and we can't
1833   // complete the type.
1834   CVType cvt = m_index->tpi().getType(TypeIndex(type_id.index));
1835   if (IsForwardRefUdt(cvt))
1836     return false;
1837 
1838   auto types_iter = m_types.find(status.uid);
1839   lldbassert(types_iter != m_types.end());
1840 
1841   if (cvt.kind() == LF_MODIFIER) {
1842     TypeIndex unmodified_type = LookThroughModifierRecord(cvt);
1843     cvt = m_index->tpi().getType(unmodified_type);
1844     // LF_MODIFIERS usually point to forward decls, so this is the one case
1845     // where we won't have been able to resolve a forward decl to a full decl
1846     // earlier on.  So we need to do that now.
1847     if (IsForwardRefUdt(cvt)) {
1848       llvm::Expected<TypeIndex> expected_full_ti =
1849           m_index->tpi().findFullDeclForForwardRef(unmodified_type);
1850       if (!expected_full_ti) {
1851         llvm::consumeError(expected_full_ti.takeError());
1852         return false;
1853       }
1854       cvt = m_index->tpi().getType(*expected_full_ti);
1855       lldbassert(!IsForwardRefUdt(cvt));
1856       unmodified_type = *expected_full_ti;
1857     }
1858     type_id = PdbTypeSymId(unmodified_type, false);
1859   }
1860   TypeIndex field_list_ti = GetFieldListIndex(cvt);
1861   CVType field_list_cvt = m_index->tpi().getType(field_list_ti);
1862   if (field_list_cvt.kind() != LF_FIELDLIST)
1863     return false;
1864 
1865   // Visit all members of this class, then perform any finalization necessary
1866   // to complete the class.
1867   UdtRecordCompleter completer(type_id, compiler_type, *tag_decl, *this);
1868   auto error =
1869       llvm::codeview::visitMemberRecordStream(field_list_cvt.data(), completer);
1870   completer.complete();
1871 
1872   status.status = Type::eResolveStateFull;
1873   if (!error)
1874     return true;
1875 
1876   llvm::consumeError(std::move(error));
1877   return false;
1878 }
1879 
1880 size_t SymbolFileNativePDB::GetTypes(lldb_private::SymbolContextScope *sc_scope,
1881                                      TypeClass type_mask,
1882                                      lldb_private::TypeList &type_list) {
1883   return 0;
1884 }
1885 
1886 CompilerDeclContext
1887 SymbolFileNativePDB::FindNamespace(const SymbolContext &sc,
1888                                    const ConstString &name,
1889                                    const CompilerDeclContext *parent_decl_ctx) {
1890   return {};
1891 }
1892 
1893 TypeSystem *
1894 SymbolFileNativePDB::GetTypeSystemForLanguage(lldb::LanguageType language) {
1895   auto type_system =
1896       m_obj_file->GetModule()->GetTypeSystemForLanguage(language);
1897   if (type_system)
1898     type_system->SetSymbolFile(this);
1899   return type_system;
1900 }
1901 
1902 ConstString SymbolFileNativePDB::GetPluginName() {
1903   static ConstString g_name("pdb");
1904   return g_name;
1905 }
1906 
1907 uint32_t SymbolFileNativePDB::GetPluginVersion() { return 1; }
1908