1 //===-- PDBASTParser.cpp --------------------------------------------------===//
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 #include "PDBASTParser.h"
10 
11 #include "SymbolFilePDB.h"
12 
13 #include "clang/AST/CharUnits.h"
14 #include "clang/AST/Decl.h"
15 #include "clang/AST/DeclCXX.h"
16 
17 #include "Plugins/ExpressionParser/Clang/ClangASTMetadata.h"
18 #include "Plugins/ExpressionParser/Clang/ClangUtil.h"
19 #include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
20 #include "lldb/Core/Module.h"
21 #include "lldb/Symbol/Declaration.h"
22 #include "lldb/Symbol/SymbolFile.h"
23 #include "lldb/Symbol/TypeMap.h"
24 #include "lldb/Symbol/TypeSystem.h"
25 
26 #include "llvm/DebugInfo/PDB/IPDBLineNumber.h"
27 #include "llvm/DebugInfo/PDB/IPDBSourceFile.h"
28 #include "llvm/DebugInfo/PDB/PDBSymbol.h"
29 #include "llvm/DebugInfo/PDB/PDBSymbolData.h"
30 #include "llvm/DebugInfo/PDB/PDBSymbolFunc.h"
31 #include "llvm/DebugInfo/PDB/PDBSymbolTypeArray.h"
32 #include "llvm/DebugInfo/PDB/PDBSymbolTypeBuiltin.h"
33 #include "llvm/DebugInfo/PDB/PDBSymbolTypeEnum.h"
34 #include "llvm/DebugInfo/PDB/PDBSymbolTypeFunctionArg.h"
35 #include "llvm/DebugInfo/PDB/PDBSymbolTypeFunctionSig.h"
36 #include "llvm/DebugInfo/PDB/PDBSymbolTypePointer.h"
37 #include "llvm/DebugInfo/PDB/PDBSymbolTypeTypedef.h"
38 #include "llvm/DebugInfo/PDB/PDBSymbolTypeUDT.h"
39 
40 #include "Plugins/Language/CPlusPlus/MSVCUndecoratedNameParser.h"
41 
42 using namespace lldb;
43 using namespace lldb_private;
44 using namespace llvm::pdb;
45 
46 static int TranslateUdtKind(PDB_UdtType pdb_kind) {
47   switch (pdb_kind) {
48   case PDB_UdtType::Class:
49     return clang::TTK_Class;
50   case PDB_UdtType::Struct:
51     return clang::TTK_Struct;
52   case PDB_UdtType::Union:
53     return clang::TTK_Union;
54   case PDB_UdtType::Interface:
55     return clang::TTK_Interface;
56   }
57   llvm_unreachable("unsuported PDB UDT type");
58 }
59 
60 static lldb::Encoding TranslateBuiltinEncoding(PDB_BuiltinType type) {
61   switch (type) {
62   case PDB_BuiltinType::Float:
63     return lldb::eEncodingIEEE754;
64   case PDB_BuiltinType::Int:
65   case PDB_BuiltinType::Long:
66   case PDB_BuiltinType::Char:
67     return lldb::eEncodingSint;
68   case PDB_BuiltinType::Bool:
69   case PDB_BuiltinType::Char16:
70   case PDB_BuiltinType::Char32:
71   case PDB_BuiltinType::UInt:
72   case PDB_BuiltinType::ULong:
73   case PDB_BuiltinType::HResult:
74   case PDB_BuiltinType::WCharT:
75     return lldb::eEncodingUint;
76   default:
77     return lldb::eEncodingInvalid;
78   }
79 }
80 
81 static lldb::Encoding TranslateEnumEncoding(PDB_VariantType type) {
82   switch (type) {
83   case PDB_VariantType::Int8:
84   case PDB_VariantType::Int16:
85   case PDB_VariantType::Int32:
86   case PDB_VariantType::Int64:
87     return lldb::eEncodingSint;
88 
89   case PDB_VariantType::UInt8:
90   case PDB_VariantType::UInt16:
91   case PDB_VariantType::UInt32:
92   case PDB_VariantType::UInt64:
93     return lldb::eEncodingUint;
94 
95   default:
96     break;
97   }
98 
99   return lldb::eEncodingSint;
100 }
101 
102 static CompilerType
103 GetBuiltinTypeForPDBEncodingAndBitSize(TypeSystemClang &clang_ast,
104                                        const PDBSymbolTypeBuiltin &pdb_type,
105                                        Encoding encoding, uint32_t width) {
106   clang::ASTContext &ast = clang_ast.getASTContext();
107 
108   switch (pdb_type.getBuiltinType()) {
109   default:
110     break;
111   case PDB_BuiltinType::None:
112     return CompilerType();
113   case PDB_BuiltinType::Void:
114     return clang_ast.GetBasicType(eBasicTypeVoid);
115   case PDB_BuiltinType::Char:
116     return clang_ast.GetBasicType(eBasicTypeChar);
117   case PDB_BuiltinType::Bool:
118     return clang_ast.GetBasicType(eBasicTypeBool);
119   case PDB_BuiltinType::Long:
120     if (width == ast.getTypeSize(ast.LongTy))
121       return CompilerType(&clang_ast, ast.LongTy.getAsOpaquePtr());
122     if (width == ast.getTypeSize(ast.LongLongTy))
123       return CompilerType(&clang_ast, ast.LongLongTy.getAsOpaquePtr());
124     break;
125   case PDB_BuiltinType::ULong:
126     if (width == ast.getTypeSize(ast.UnsignedLongTy))
127       return CompilerType(&clang_ast, ast.UnsignedLongTy.getAsOpaquePtr());
128     if (width == ast.getTypeSize(ast.UnsignedLongLongTy))
129       return CompilerType(&clang_ast, ast.UnsignedLongLongTy.getAsOpaquePtr());
130     break;
131   case PDB_BuiltinType::WCharT:
132     if (width == ast.getTypeSize(ast.WCharTy))
133       return CompilerType(&clang_ast, ast.WCharTy.getAsOpaquePtr());
134     break;
135   case PDB_BuiltinType::Char16:
136     return CompilerType(&clang_ast, ast.Char16Ty.getAsOpaquePtr());
137   case PDB_BuiltinType::Char32:
138     return CompilerType(&clang_ast, ast.Char32Ty.getAsOpaquePtr());
139   case PDB_BuiltinType::Float:
140     // Note: types `long double` and `double` have same bit size in MSVC and
141     // there is no information in the PDB to distinguish them. So when falling
142     // back to default search, the compiler type of `long double` will be
143     // represented by the one generated for `double`.
144     break;
145   }
146   // If there is no match on PDB_BuiltinType, fall back to default search by
147   // encoding and width only
148   return clang_ast.GetBuiltinTypeForEncodingAndBitSize(encoding, width);
149 }
150 
151 static ConstString GetPDBBuiltinTypeName(const PDBSymbolTypeBuiltin &pdb_type,
152                                          CompilerType &compiler_type) {
153   PDB_BuiltinType kind = pdb_type.getBuiltinType();
154   switch (kind) {
155   default:
156     break;
157   case PDB_BuiltinType::Currency:
158     return ConstString("CURRENCY");
159   case PDB_BuiltinType::Date:
160     return ConstString("DATE");
161   case PDB_BuiltinType::Variant:
162     return ConstString("VARIANT");
163   case PDB_BuiltinType::Complex:
164     return ConstString("complex");
165   case PDB_BuiltinType::Bitfield:
166     return ConstString("bitfield");
167   case PDB_BuiltinType::BSTR:
168     return ConstString("BSTR");
169   case PDB_BuiltinType::HResult:
170     return ConstString("HRESULT");
171   case PDB_BuiltinType::BCD:
172     return ConstString("BCD");
173   case PDB_BuiltinType::Char16:
174     return ConstString("char16_t");
175   case PDB_BuiltinType::Char32:
176     return ConstString("char32_t");
177   case PDB_BuiltinType::None:
178     return ConstString("...");
179   }
180   return compiler_type.GetTypeName();
181 }
182 
183 static bool GetDeclarationForSymbol(const PDBSymbol &symbol,
184                                     Declaration &decl) {
185   auto &raw_sym = symbol.getRawSymbol();
186   auto first_line_up = raw_sym.getSrcLineOnTypeDefn();
187 
188   if (!first_line_up) {
189     auto lines_up = symbol.getSession().findLineNumbersByAddress(
190         raw_sym.getVirtualAddress(), raw_sym.getLength());
191     if (!lines_up)
192       return false;
193     first_line_up = lines_up->getNext();
194     if (!first_line_up)
195       return false;
196   }
197   uint32_t src_file_id = first_line_up->getSourceFileId();
198   auto src_file_up = symbol.getSession().getSourceFileById(src_file_id);
199   if (!src_file_up)
200     return false;
201 
202   FileSpec spec(src_file_up->getFileName());
203   decl.SetFile(spec);
204   decl.SetColumn(first_line_up->getColumnNumber());
205   decl.SetLine(first_line_up->getLineNumber());
206   return true;
207 }
208 
209 static AccessType TranslateMemberAccess(PDB_MemberAccess access) {
210   switch (access) {
211   case PDB_MemberAccess::Private:
212     return eAccessPrivate;
213   case PDB_MemberAccess::Protected:
214     return eAccessProtected;
215   case PDB_MemberAccess::Public:
216     return eAccessPublic;
217   }
218   return eAccessNone;
219 }
220 
221 static AccessType GetDefaultAccessibilityForUdtKind(PDB_UdtType udt_kind) {
222   switch (udt_kind) {
223   case PDB_UdtType::Struct:
224   case PDB_UdtType::Union:
225     return eAccessPublic;
226   case PDB_UdtType::Class:
227   case PDB_UdtType::Interface:
228     return eAccessPrivate;
229   }
230   llvm_unreachable("unsupported PDB UDT type");
231 }
232 
233 static AccessType GetAccessibilityForUdt(const PDBSymbolTypeUDT &udt) {
234   AccessType access = TranslateMemberAccess(udt.getAccess());
235   if (access != lldb::eAccessNone || !udt.isNested())
236     return access;
237 
238   auto parent = udt.getClassParent();
239   if (!parent)
240     return lldb::eAccessNone;
241 
242   auto parent_udt = llvm::dyn_cast<PDBSymbolTypeUDT>(parent.get());
243   if (!parent_udt)
244     return lldb::eAccessNone;
245 
246   return GetDefaultAccessibilityForUdtKind(parent_udt->getUdtKind());
247 }
248 
249 static clang::MSInheritanceAttr::Spelling
250 GetMSInheritance(const PDBSymbolTypeUDT &udt) {
251   int base_count = 0;
252   bool has_virtual = false;
253 
254   auto bases_enum = udt.findAllChildren<PDBSymbolTypeBaseClass>();
255   if (bases_enum) {
256     while (auto base = bases_enum->getNext()) {
257       base_count++;
258       has_virtual |= base->isVirtualBaseClass();
259     }
260   }
261 
262   if (has_virtual)
263     return clang::MSInheritanceAttr::Keyword_virtual_inheritance;
264   if (base_count > 1)
265     return clang::MSInheritanceAttr::Keyword_multiple_inheritance;
266   return clang::MSInheritanceAttr::Keyword_single_inheritance;
267 }
268 
269 static std::unique_ptr<llvm::pdb::PDBSymbol>
270 GetClassOrFunctionParent(const llvm::pdb::PDBSymbol &symbol) {
271   const IPDBSession &session = symbol.getSession();
272   const IPDBRawSymbol &raw = symbol.getRawSymbol();
273   auto tag = symbol.getSymTag();
274 
275   // For items that are nested inside of a class, return the class that it is
276   // nested inside of.
277   // Note that only certain items can be nested inside of classes.
278   switch (tag) {
279   case PDB_SymType::Function:
280   case PDB_SymType::Data:
281   case PDB_SymType::UDT:
282   case PDB_SymType::Enum:
283   case PDB_SymType::FunctionSig:
284   case PDB_SymType::Typedef:
285   case PDB_SymType::BaseClass:
286   case PDB_SymType::VTable: {
287     auto class_parent_id = raw.getClassParentId();
288     if (auto class_parent = session.getSymbolById(class_parent_id))
289       return class_parent;
290     break;
291   }
292   default:
293     break;
294   }
295 
296   // Otherwise, if it is nested inside of a function, return the function.
297   // Note that only certain items can be nested inside of functions.
298   switch (tag) {
299   case PDB_SymType::Block:
300   case PDB_SymType::Data: {
301     auto lexical_parent_id = raw.getLexicalParentId();
302     auto lexical_parent = session.getSymbolById(lexical_parent_id);
303     if (!lexical_parent)
304       return nullptr;
305 
306     auto lexical_parent_tag = lexical_parent->getSymTag();
307     if (lexical_parent_tag == PDB_SymType::Function)
308       return lexical_parent;
309     if (lexical_parent_tag == PDB_SymType::Exe)
310       return nullptr;
311 
312     return GetClassOrFunctionParent(*lexical_parent);
313   }
314   default:
315     return nullptr;
316   }
317 }
318 
319 static clang::NamedDecl *
320 GetDeclFromContextByName(const clang::ASTContext &ast,
321                          const clang::DeclContext &decl_context,
322                          llvm::StringRef name) {
323   clang::IdentifierInfo &ident = ast.Idents.get(name);
324   clang::DeclarationName decl_name = ast.DeclarationNames.getIdentifier(&ident);
325   clang::DeclContext::lookup_result result = decl_context.lookup(decl_name);
326   if (result.empty())
327     return nullptr;
328 
329   return result[0];
330 }
331 
332 static bool IsAnonymousNamespaceName(llvm::StringRef name) {
333   return name == "`anonymous namespace'" || name == "`anonymous-namespace'";
334 }
335 
336 static clang::CallingConv TranslateCallingConvention(PDB_CallingConv pdb_cc) {
337   switch (pdb_cc) {
338   case llvm::codeview::CallingConvention::NearC:
339     return clang::CC_C;
340   case llvm::codeview::CallingConvention::NearStdCall:
341     return clang::CC_X86StdCall;
342   case llvm::codeview::CallingConvention::NearFast:
343     return clang::CC_X86FastCall;
344   case llvm::codeview::CallingConvention::ThisCall:
345     return clang::CC_X86ThisCall;
346   case llvm::codeview::CallingConvention::NearVector:
347     return clang::CC_X86VectorCall;
348   case llvm::codeview::CallingConvention::NearPascal:
349     return clang::CC_X86Pascal;
350   default:
351     assert(false && "Unknown calling convention");
352     return clang::CC_C;
353   }
354 }
355 
356 PDBASTParser::PDBASTParser(lldb_private::TypeSystemClang &ast) : m_ast(ast) {}
357 
358 PDBASTParser::~PDBASTParser() {}
359 
360 // DebugInfoASTParser interface
361 
362 lldb::TypeSP PDBASTParser::CreateLLDBTypeFromPDBType(const PDBSymbol &type) {
363   Declaration decl;
364   switch (type.getSymTag()) {
365   case PDB_SymType::BaseClass: {
366     auto symbol_file = m_ast.GetSymbolFile();
367     if (!symbol_file)
368       return nullptr;
369 
370     auto ty = symbol_file->ResolveTypeUID(type.getRawSymbol().getTypeId());
371     return ty ? ty->shared_from_this() : nullptr;
372   } break;
373   case PDB_SymType::UDT: {
374     auto udt = llvm::dyn_cast<PDBSymbolTypeUDT>(&type);
375     assert(udt);
376 
377     // Note that, unnamed UDT being typedef-ed is generated as a UDT symbol
378     // other than a Typedef symbol in PDB. For example,
379     //    typedef union { short Row; short Col; } Union;
380     // is generated as a named UDT in PDB:
381     //    union Union { short Row; short Col; }
382     // Such symbols will be handled here.
383 
384     // Some UDT with trival ctor has zero length. Just ignore.
385     if (udt->getLength() == 0)
386       return nullptr;
387 
388     // Ignore unnamed-tag UDTs.
389     std::string name =
390         std::string(MSVCUndecoratedNameParser::DropScope(udt->getName()));
391     if (name.empty())
392       return nullptr;
393 
394     auto decl_context = GetDeclContextContainingSymbol(type);
395 
396     // Check if such an UDT already exists in the current context.
397     // This may occur with const or volatile types. There are separate type
398     // symbols in PDB for types with const or volatile modifiers, but we need
399     // to create only one declaration for them all.
400     Type::ResolveState type_resolve_state;
401     CompilerType clang_type = m_ast.GetTypeForIdentifier<clang::CXXRecordDecl>(
402         ConstString(name), decl_context);
403     if (!clang_type.IsValid()) {
404       auto access = GetAccessibilityForUdt(*udt);
405 
406       auto tag_type_kind = TranslateUdtKind(udt->getUdtKind());
407 
408       ClangASTMetadata metadata;
409       metadata.SetUserID(type.getSymIndexId());
410       metadata.SetIsDynamicCXXType(false);
411 
412       clang_type = m_ast.CreateRecordType(
413           decl_context, OptionalClangModuleID(), access, name, tag_type_kind,
414           lldb::eLanguageTypeC_plus_plus, &metadata);
415       assert(clang_type.IsValid());
416 
417       auto record_decl =
418           m_ast.GetAsCXXRecordDecl(clang_type.GetOpaqueQualType());
419       assert(record_decl);
420       m_uid_to_decl[type.getSymIndexId()] = record_decl;
421 
422       auto inheritance_attr = clang::MSInheritanceAttr::CreateImplicit(
423           m_ast.getASTContext(), GetMSInheritance(*udt));
424       record_decl->addAttr(inheritance_attr);
425 
426       TypeSystemClang::StartTagDeclarationDefinition(clang_type);
427 
428       auto children = udt->findAllChildren();
429       if (!children || children->getChildCount() == 0) {
430         // PDB does not have symbol of forwarder. We assume we get an udt w/o
431         // any fields. Just complete it at this point.
432         TypeSystemClang::CompleteTagDeclarationDefinition(clang_type);
433 
434         TypeSystemClang::SetHasExternalStorage(clang_type.GetOpaqueQualType(),
435                                                false);
436 
437         type_resolve_state = Type::ResolveState::Full;
438       } else {
439         // Add the type to the forward declarations. It will help us to avoid
440         // an endless recursion in CompleteTypeFromUdt function.
441         m_forward_decl_to_uid[record_decl] = type.getSymIndexId();
442 
443         TypeSystemClang::SetHasExternalStorage(clang_type.GetOpaqueQualType(),
444                                                true);
445 
446         type_resolve_state = Type::ResolveState::Forward;
447       }
448     } else
449       type_resolve_state = Type::ResolveState::Forward;
450 
451     if (udt->isConstType())
452       clang_type = clang_type.AddConstModifier();
453 
454     if (udt->isVolatileType())
455       clang_type = clang_type.AddVolatileModifier();
456 
457     GetDeclarationForSymbol(type, decl);
458     return std::make_shared<lldb_private::Type>(
459         type.getSymIndexId(), m_ast.GetSymbolFile(), ConstString(name),
460         udt->getLength(), nullptr, LLDB_INVALID_UID,
461         lldb_private::Type::eEncodingIsUID, decl, clang_type,
462         type_resolve_state);
463   } break;
464   case PDB_SymType::Enum: {
465     auto enum_type = llvm::dyn_cast<PDBSymbolTypeEnum>(&type);
466     assert(enum_type);
467 
468     std::string name =
469         std::string(MSVCUndecoratedNameParser::DropScope(enum_type->getName()));
470     auto decl_context = GetDeclContextContainingSymbol(type);
471     uint64_t bytes = enum_type->getLength();
472 
473     // Check if such an enum already exists in the current context
474     CompilerType ast_enum = m_ast.GetTypeForIdentifier<clang::EnumDecl>(
475         ConstString(name), decl_context);
476     if (!ast_enum.IsValid()) {
477       auto underlying_type_up = enum_type->getUnderlyingType();
478       if (!underlying_type_up)
479         return nullptr;
480 
481       lldb::Encoding encoding =
482           TranslateBuiltinEncoding(underlying_type_up->getBuiltinType());
483       // FIXME: Type of underlying builtin is always `Int`. We correct it with
484       // the very first enumerator's encoding if any.
485       auto first_child = enum_type->findOneChild<PDBSymbolData>();
486       if (first_child)
487         encoding = TranslateEnumEncoding(first_child->getValue().Type);
488 
489       CompilerType builtin_type;
490       if (bytes > 0)
491         builtin_type = GetBuiltinTypeForPDBEncodingAndBitSize(
492             m_ast, *underlying_type_up, encoding, bytes * 8);
493       else
494         builtin_type = m_ast.GetBasicType(eBasicTypeInt);
495 
496       // FIXME: PDB does not have information about scoped enumeration (Enum
497       // Class). Set it false for now.
498       bool isScoped = false;
499 
500       ast_enum = m_ast.CreateEnumerationType(name.c_str(), decl_context,
501                                              OptionalClangModuleID(), decl,
502                                              builtin_type, isScoped);
503 
504       auto enum_decl = TypeSystemClang::GetAsEnumDecl(ast_enum);
505       assert(enum_decl);
506       m_uid_to_decl[type.getSymIndexId()] = enum_decl;
507 
508       auto enum_values = enum_type->findAllChildren<PDBSymbolData>();
509       if (enum_values) {
510         while (auto enum_value = enum_values->getNext()) {
511           if (enum_value->getDataKind() != PDB_DataKind::Constant)
512             continue;
513           AddEnumValue(ast_enum, *enum_value);
514         }
515       }
516 
517       if (TypeSystemClang::StartTagDeclarationDefinition(ast_enum))
518         TypeSystemClang::CompleteTagDeclarationDefinition(ast_enum);
519     }
520 
521     if (enum_type->isConstType())
522       ast_enum = ast_enum.AddConstModifier();
523 
524     if (enum_type->isVolatileType())
525       ast_enum = ast_enum.AddVolatileModifier();
526 
527     GetDeclarationForSymbol(type, decl);
528     return std::make_shared<lldb_private::Type>(
529         type.getSymIndexId(), m_ast.GetSymbolFile(), ConstString(name), bytes,
530         nullptr, LLDB_INVALID_UID, lldb_private::Type::eEncodingIsUID, decl,
531         ast_enum, lldb_private::Type::ResolveState::Full);
532   } break;
533   case PDB_SymType::Typedef: {
534     auto type_def = llvm::dyn_cast<PDBSymbolTypeTypedef>(&type);
535     assert(type_def);
536 
537     lldb_private::Type *target_type =
538         m_ast.GetSymbolFile()->ResolveTypeUID(type_def->getTypeId());
539     if (!target_type)
540       return nullptr;
541 
542     std::string name =
543         std::string(MSVCUndecoratedNameParser::DropScope(type_def->getName()));
544     auto decl_ctx = GetDeclContextContainingSymbol(type);
545 
546     // Check if such a typedef already exists in the current context
547     CompilerType ast_typedef =
548         m_ast.GetTypeForIdentifier<clang::TypedefNameDecl>(ConstString(name),
549                                                            decl_ctx);
550     if (!ast_typedef.IsValid()) {
551       CompilerType target_ast_type = target_type->GetFullCompilerType();
552 
553       ast_typedef = target_ast_type.CreateTypedef(
554           name.c_str(), m_ast.CreateDeclContext(decl_ctx), 0);
555       if (!ast_typedef)
556         return nullptr;
557 
558       auto typedef_decl = TypeSystemClang::GetAsTypedefDecl(ast_typedef);
559       assert(typedef_decl);
560       m_uid_to_decl[type.getSymIndexId()] = typedef_decl;
561     }
562 
563     if (type_def->isConstType())
564       ast_typedef = ast_typedef.AddConstModifier();
565 
566     if (type_def->isVolatileType())
567       ast_typedef = ast_typedef.AddVolatileModifier();
568 
569     GetDeclarationForSymbol(type, decl);
570     llvm::Optional<uint64_t> size;
571     if (type_def->getLength())
572       size = type_def->getLength();
573     return std::make_shared<lldb_private::Type>(
574         type_def->getSymIndexId(), m_ast.GetSymbolFile(), ConstString(name),
575         size, nullptr, target_type->GetID(),
576         lldb_private::Type::eEncodingIsTypedefUID, decl, ast_typedef,
577         lldb_private::Type::ResolveState::Full);
578   } break;
579   case PDB_SymType::Function:
580   case PDB_SymType::FunctionSig: {
581     std::string name;
582     PDBSymbolTypeFunctionSig *func_sig = nullptr;
583     if (auto pdb_func = llvm::dyn_cast<PDBSymbolFunc>(&type)) {
584       if (pdb_func->isCompilerGenerated())
585         return nullptr;
586 
587       auto sig = pdb_func->getSignature();
588       if (!sig)
589         return nullptr;
590       func_sig = sig.release();
591       // Function type is named.
592       name = std::string(
593           MSVCUndecoratedNameParser::DropScope(pdb_func->getName()));
594     } else if (auto pdb_func_sig =
595                    llvm::dyn_cast<PDBSymbolTypeFunctionSig>(&type)) {
596       func_sig = const_cast<PDBSymbolTypeFunctionSig *>(pdb_func_sig);
597     } else
598       llvm_unreachable("Unexpected PDB symbol!");
599 
600     auto arg_enum = func_sig->getArguments();
601     uint32_t num_args = arg_enum->getChildCount();
602     std::vector<CompilerType> arg_list;
603 
604     bool is_variadic = func_sig->isCVarArgs();
605     // Drop last variadic argument.
606     if (is_variadic)
607       --num_args;
608     for (uint32_t arg_idx = 0; arg_idx < num_args; arg_idx++) {
609       auto arg = arg_enum->getChildAtIndex(arg_idx);
610       if (!arg)
611         break;
612       lldb_private::Type *arg_type =
613           m_ast.GetSymbolFile()->ResolveTypeUID(arg->getSymIndexId());
614       // If there's some error looking up one of the dependent types of this
615       // function signature, bail.
616       if (!arg_type)
617         return nullptr;
618       CompilerType arg_ast_type = arg_type->GetFullCompilerType();
619       arg_list.push_back(arg_ast_type);
620     }
621     lldbassert(arg_list.size() <= num_args);
622 
623     auto pdb_return_type = func_sig->getReturnType();
624     lldb_private::Type *return_type =
625         m_ast.GetSymbolFile()->ResolveTypeUID(pdb_return_type->getSymIndexId());
626     // If there's some error looking up one of the dependent types of this
627     // function signature, bail.
628     if (!return_type)
629       return nullptr;
630     CompilerType return_ast_type = return_type->GetFullCompilerType();
631     uint32_t type_quals = 0;
632     if (func_sig->isConstType())
633       type_quals |= clang::Qualifiers::Const;
634     if (func_sig->isVolatileType())
635       type_quals |= clang::Qualifiers::Volatile;
636     auto cc = TranslateCallingConvention(func_sig->getCallingConvention());
637     CompilerType func_sig_ast_type =
638         m_ast.CreateFunctionType(return_ast_type, arg_list.data(),
639                                  arg_list.size(), is_variadic, type_quals, cc);
640 
641     GetDeclarationForSymbol(type, decl);
642     return std::make_shared<lldb_private::Type>(
643         type.getSymIndexId(), m_ast.GetSymbolFile(), ConstString(name),
644         llvm::None, nullptr, LLDB_INVALID_UID,
645         lldb_private::Type::eEncodingIsUID, decl, func_sig_ast_type,
646         lldb_private::Type::ResolveState::Full);
647   } break;
648   case PDB_SymType::ArrayType: {
649     auto array_type = llvm::dyn_cast<PDBSymbolTypeArray>(&type);
650     assert(array_type);
651     uint32_t num_elements = array_type->getCount();
652     uint32_t element_uid = array_type->getElementTypeId();
653     llvm::Optional<uint64_t> bytes;
654     if (uint64_t size = array_type->getLength())
655       bytes = size;
656 
657     // If array rank > 0, PDB gives the element type at N=0. So element type
658     // will parsed in the order N=0, N=1,..., N=rank sequentially.
659     lldb_private::Type *element_type =
660         m_ast.GetSymbolFile()->ResolveTypeUID(element_uid);
661     if (!element_type)
662       return nullptr;
663 
664     CompilerType element_ast_type = element_type->GetForwardCompilerType();
665     // If element type is UDT, it needs to be complete.
666     if (TypeSystemClang::IsCXXClassType(element_ast_type) &&
667         !element_ast_type.GetCompleteType()) {
668       if (TypeSystemClang::StartTagDeclarationDefinition(element_ast_type)) {
669         TypeSystemClang::CompleteTagDeclarationDefinition(element_ast_type);
670       } else {
671         // We are not able to start defintion.
672         return nullptr;
673       }
674     }
675     CompilerType array_ast_type = m_ast.CreateArrayType(
676         element_ast_type, num_elements, /*is_gnu_vector*/ false);
677     TypeSP type_sp = std::make_shared<lldb_private::Type>(
678         array_type->getSymIndexId(), m_ast.GetSymbolFile(), ConstString(),
679         bytes, nullptr, LLDB_INVALID_UID, lldb_private::Type::eEncodingIsUID,
680         decl, array_ast_type, lldb_private::Type::ResolveState::Full);
681     type_sp->SetEncodingType(element_type);
682     return type_sp;
683   } break;
684   case PDB_SymType::BuiltinType: {
685     auto *builtin_type = llvm::dyn_cast<PDBSymbolTypeBuiltin>(&type);
686     assert(builtin_type);
687     PDB_BuiltinType builtin_kind = builtin_type->getBuiltinType();
688     if (builtin_kind == PDB_BuiltinType::None)
689       return nullptr;
690 
691     llvm::Optional<uint64_t> bytes;
692     if (uint64_t size = builtin_type->getLength())
693       bytes = size;
694     Encoding encoding = TranslateBuiltinEncoding(builtin_kind);
695     CompilerType builtin_ast_type = GetBuiltinTypeForPDBEncodingAndBitSize(
696         m_ast, *builtin_type, encoding, bytes.getValueOr(0) * 8);
697 
698     if (builtin_type->isConstType())
699       builtin_ast_type = builtin_ast_type.AddConstModifier();
700 
701     if (builtin_type->isVolatileType())
702       builtin_ast_type = builtin_ast_type.AddVolatileModifier();
703 
704     auto type_name = GetPDBBuiltinTypeName(*builtin_type, builtin_ast_type);
705 
706     return std::make_shared<lldb_private::Type>(
707         builtin_type->getSymIndexId(), m_ast.GetSymbolFile(), type_name, bytes,
708         nullptr, LLDB_INVALID_UID, lldb_private::Type::eEncodingIsUID, decl,
709         builtin_ast_type, lldb_private::Type::ResolveState::Full);
710   } break;
711   case PDB_SymType::PointerType: {
712     auto *pointer_type = llvm::dyn_cast<PDBSymbolTypePointer>(&type);
713     assert(pointer_type);
714     Type *pointee_type = m_ast.GetSymbolFile()->ResolveTypeUID(
715         pointer_type->getPointeeType()->getSymIndexId());
716     if (!pointee_type)
717       return nullptr;
718 
719     if (pointer_type->isPointerToDataMember() ||
720         pointer_type->isPointerToMemberFunction()) {
721       auto class_parent_uid = pointer_type->getRawSymbol().getClassParentId();
722       auto class_parent_type =
723           m_ast.GetSymbolFile()->ResolveTypeUID(class_parent_uid);
724       assert(class_parent_type);
725 
726       CompilerType pointer_ast_type;
727       pointer_ast_type = TypeSystemClang::CreateMemberPointerType(
728           class_parent_type->GetLayoutCompilerType(),
729           pointee_type->GetForwardCompilerType());
730       assert(pointer_ast_type);
731 
732       return std::make_shared<lldb_private::Type>(
733           pointer_type->getSymIndexId(), m_ast.GetSymbolFile(), ConstString(),
734           pointer_type->getLength(), nullptr, LLDB_INVALID_UID,
735           lldb_private::Type::eEncodingIsUID, decl, pointer_ast_type,
736           lldb_private::Type::ResolveState::Forward);
737     }
738 
739     CompilerType pointer_ast_type;
740     pointer_ast_type = pointee_type->GetFullCompilerType();
741     if (pointer_type->isReference())
742       pointer_ast_type = pointer_ast_type.GetLValueReferenceType();
743     else if (pointer_type->isRValueReference())
744       pointer_ast_type = pointer_ast_type.GetRValueReferenceType();
745     else
746       pointer_ast_type = pointer_ast_type.GetPointerType();
747 
748     if (pointer_type->isConstType())
749       pointer_ast_type = pointer_ast_type.AddConstModifier();
750 
751     if (pointer_type->isVolatileType())
752       pointer_ast_type = pointer_ast_type.AddVolatileModifier();
753 
754     if (pointer_type->isRestrictedType())
755       pointer_ast_type = pointer_ast_type.AddRestrictModifier();
756 
757     return std::make_shared<lldb_private::Type>(
758         pointer_type->getSymIndexId(), m_ast.GetSymbolFile(), ConstString(),
759         pointer_type->getLength(), nullptr, LLDB_INVALID_UID,
760         lldb_private::Type::eEncodingIsUID, decl, pointer_ast_type,
761         lldb_private::Type::ResolveState::Full);
762   } break;
763   default:
764     break;
765   }
766   return nullptr;
767 }
768 
769 bool PDBASTParser::CompleteTypeFromPDB(
770     lldb_private::CompilerType &compiler_type) {
771   if (GetClangASTImporter().CanImport(compiler_type))
772     return GetClangASTImporter().CompleteType(compiler_type);
773 
774   // Remove the type from the forward declarations to avoid
775   // an endless recursion for types like a linked list.
776   clang::CXXRecordDecl *record_decl =
777       m_ast.GetAsCXXRecordDecl(compiler_type.GetOpaqueQualType());
778   auto uid_it = m_forward_decl_to_uid.find(record_decl);
779   if (uid_it == m_forward_decl_to_uid.end())
780     return true;
781 
782   auto symbol_file = static_cast<SymbolFilePDB *>(m_ast.GetSymbolFile());
783   if (!symbol_file)
784     return false;
785 
786   std::unique_ptr<PDBSymbol> symbol =
787       symbol_file->GetPDBSession().getSymbolById(uid_it->getSecond());
788   if (!symbol)
789     return false;
790 
791   m_forward_decl_to_uid.erase(uid_it);
792 
793   TypeSystemClang::SetHasExternalStorage(compiler_type.GetOpaqueQualType(),
794                                          false);
795 
796   switch (symbol->getSymTag()) {
797   case PDB_SymType::UDT: {
798     auto udt = llvm::dyn_cast<PDBSymbolTypeUDT>(symbol.get());
799     if (!udt)
800       return false;
801 
802     return CompleteTypeFromUDT(*symbol_file, compiler_type, *udt);
803   }
804   default:
805     llvm_unreachable("not a forward clang type decl!");
806   }
807 }
808 
809 clang::Decl *
810 PDBASTParser::GetDeclForSymbol(const llvm::pdb::PDBSymbol &symbol) {
811   uint32_t sym_id = symbol.getSymIndexId();
812   auto it = m_uid_to_decl.find(sym_id);
813   if (it != m_uid_to_decl.end())
814     return it->second;
815 
816   auto symbol_file = static_cast<SymbolFilePDB *>(m_ast.GetSymbolFile());
817   if (!symbol_file)
818     return nullptr;
819 
820   // First of all, check if the symbol is a member of a class. Resolve the full
821   // class type and return the declaration from the cache if so.
822   auto tag = symbol.getSymTag();
823   if (tag == PDB_SymType::Data || tag == PDB_SymType::Function) {
824     const IPDBSession &session = symbol.getSession();
825     const IPDBRawSymbol &raw = symbol.getRawSymbol();
826 
827     auto class_parent_id = raw.getClassParentId();
828     if (std::unique_ptr<PDBSymbol> class_parent =
829             session.getSymbolById(class_parent_id)) {
830       auto class_parent_type = symbol_file->ResolveTypeUID(class_parent_id);
831       if (!class_parent_type)
832         return nullptr;
833 
834       CompilerType class_parent_ct = class_parent_type->GetFullCompilerType();
835 
836       // Look a declaration up in the cache after completing the class
837       clang::Decl *decl = m_uid_to_decl.lookup(sym_id);
838       if (decl)
839         return decl;
840 
841       // A declaration was not found in the cache. It means that the symbol
842       // has the class parent, but the class doesn't have the symbol in its
843       // children list.
844       if (auto func = llvm::dyn_cast_or_null<PDBSymbolFunc>(&symbol)) {
845         // Try to find a class child method with the same RVA and use its
846         // declaration if found.
847         if (uint32_t rva = func->getRelativeVirtualAddress()) {
848           if (std::unique_ptr<ConcreteSymbolEnumerator<PDBSymbolFunc>>
849                   methods_enum =
850                       class_parent->findAllChildren<PDBSymbolFunc>()) {
851             while (std::unique_ptr<PDBSymbolFunc> method =
852                        methods_enum->getNext()) {
853               if (method->getRelativeVirtualAddress() == rva) {
854                 decl = m_uid_to_decl.lookup(method->getSymIndexId());
855                 if (decl)
856                   break;
857               }
858             }
859           }
860         }
861 
862         // If no class methods with the same RVA were found, then create a new
863         // method. It is possible for template methods.
864         if (!decl)
865           decl = AddRecordMethod(*symbol_file, class_parent_ct, *func);
866       }
867 
868       if (decl)
869         m_uid_to_decl[sym_id] = decl;
870 
871       return decl;
872     }
873   }
874 
875   // If we are here, then the symbol is not belonging to a class and is not
876   // contained in the cache. So create a declaration for it.
877   switch (symbol.getSymTag()) {
878   case PDB_SymType::Data: {
879     auto data = llvm::dyn_cast<PDBSymbolData>(&symbol);
880     assert(data);
881 
882     auto decl_context = GetDeclContextContainingSymbol(symbol);
883     assert(decl_context);
884 
885     // May be the current context is a class really, but we haven't found
886     // any class parent. This happens e.g. in the case of class static
887     // variables - they has two symbols, one is a child of the class when
888     // another is a child of the exe. So always complete the parent and use
889     // an existing declaration if possible.
890     if (auto parent_decl = llvm::dyn_cast_or_null<clang::TagDecl>(decl_context))
891       m_ast.GetCompleteDecl(parent_decl);
892 
893     std::string name =
894         std::string(MSVCUndecoratedNameParser::DropScope(data->getName()));
895 
896     // Check if the current context already contains the symbol with the name.
897     clang::Decl *decl =
898         GetDeclFromContextByName(m_ast.getASTContext(), *decl_context, name);
899     if (!decl) {
900       auto type = symbol_file->ResolveTypeUID(data->getTypeId());
901       if (!type)
902         return nullptr;
903 
904       decl = m_ast.CreateVariableDeclaration(
905           decl_context, OptionalClangModuleID(), name.c_str(),
906           ClangUtil::GetQualType(type->GetLayoutCompilerType()));
907     }
908 
909     m_uid_to_decl[sym_id] = decl;
910 
911     return decl;
912   }
913   case PDB_SymType::Function: {
914     auto func = llvm::dyn_cast<PDBSymbolFunc>(&symbol);
915     assert(func);
916 
917     auto decl_context = GetDeclContextContainingSymbol(symbol);
918     assert(decl_context);
919 
920     std::string name =
921         std::string(MSVCUndecoratedNameParser::DropScope(func->getName()));
922 
923     Type *type = symbol_file->ResolveTypeUID(sym_id);
924     if (!type)
925       return nullptr;
926 
927     auto storage = func->isStatic() ? clang::StorageClass::SC_Static
928                                     : clang::StorageClass::SC_None;
929 
930     auto decl = m_ast.CreateFunctionDeclaration(
931         decl_context, OptionalClangModuleID(), name,
932         type->GetForwardCompilerType(), storage, func->hasInlineAttribute());
933 
934     std::vector<clang::ParmVarDecl *> params;
935     if (std::unique_ptr<PDBSymbolTypeFunctionSig> sig = func->getSignature()) {
936       if (std::unique_ptr<ConcreteSymbolEnumerator<PDBSymbolTypeFunctionArg>>
937               arg_enum = sig->findAllChildren<PDBSymbolTypeFunctionArg>()) {
938         while (std::unique_ptr<PDBSymbolTypeFunctionArg> arg =
939                    arg_enum->getNext()) {
940           Type *arg_type = symbol_file->ResolveTypeUID(arg->getTypeId());
941           if (!arg_type)
942             continue;
943 
944           clang::ParmVarDecl *param = m_ast.CreateParameterDeclaration(
945               decl, OptionalClangModuleID(), nullptr,
946               arg_type->GetForwardCompilerType(), clang::SC_None, true);
947           if (param)
948             params.push_back(param);
949         }
950       }
951     }
952     if (params.size())
953       m_ast.SetFunctionParameters(decl, params.data(), params.size());
954 
955     m_uid_to_decl[sym_id] = decl;
956 
957     return decl;
958   }
959   default: {
960     // It's not a variable and not a function, check if it's a type
961     Type *type = symbol_file->ResolveTypeUID(sym_id);
962     if (!type)
963       return nullptr;
964 
965     return m_uid_to_decl.lookup(sym_id);
966   }
967   }
968 }
969 
970 clang::DeclContext *
971 PDBASTParser::GetDeclContextForSymbol(const llvm::pdb::PDBSymbol &symbol) {
972   if (symbol.getSymTag() == PDB_SymType::Function) {
973     clang::DeclContext *result =
974         llvm::dyn_cast_or_null<clang::FunctionDecl>(GetDeclForSymbol(symbol));
975 
976     if (result)
977       m_decl_context_to_uid[result] = symbol.getSymIndexId();
978 
979     return result;
980   }
981 
982   auto symbol_file = static_cast<SymbolFilePDB *>(m_ast.GetSymbolFile());
983   if (!symbol_file)
984     return nullptr;
985 
986   auto type = symbol_file->ResolveTypeUID(symbol.getSymIndexId());
987   if (!type)
988     return nullptr;
989 
990   clang::DeclContext *result =
991       m_ast.GetDeclContextForType(type->GetForwardCompilerType());
992 
993   if (result)
994     m_decl_context_to_uid[result] = symbol.getSymIndexId();
995 
996   return result;
997 }
998 
999 clang::DeclContext *PDBASTParser::GetDeclContextContainingSymbol(
1000     const llvm::pdb::PDBSymbol &symbol) {
1001   auto parent = GetClassOrFunctionParent(symbol);
1002   while (parent) {
1003     if (auto parent_context = GetDeclContextForSymbol(*parent))
1004       return parent_context;
1005 
1006     parent = GetClassOrFunctionParent(*parent);
1007   }
1008 
1009   // We can't find any class or function parent of the symbol. So analyze
1010   // the full symbol name. The symbol may be belonging to a namespace
1011   // or function (or even to a class if it's e.g. a static variable symbol).
1012 
1013   // TODO: Make clang to emit full names for variables in namespaces
1014   // (as MSVC does)
1015 
1016   std::string name(symbol.getRawSymbol().getName());
1017   MSVCUndecoratedNameParser parser(name);
1018   llvm::ArrayRef<MSVCUndecoratedNameSpecifier> specs = parser.GetSpecifiers();
1019   if (specs.empty())
1020     return m_ast.GetTranslationUnitDecl();
1021 
1022   auto symbol_file = static_cast<SymbolFilePDB *>(m_ast.GetSymbolFile());
1023   if (!symbol_file)
1024     return m_ast.GetTranslationUnitDecl();
1025 
1026   auto global = symbol_file->GetPDBSession().getGlobalScope();
1027   if (!global)
1028     return m_ast.GetTranslationUnitDecl();
1029 
1030   bool has_type_or_function_parent = false;
1031   clang::DeclContext *curr_context = m_ast.GetTranslationUnitDecl();
1032   for (std::size_t i = 0; i < specs.size() - 1; i++) {
1033     // Check if there is a function or a type with the current context's name.
1034     if (std::unique_ptr<IPDBEnumSymbols> children_enum = global->findChildren(
1035             PDB_SymType::None, specs[i].GetFullName(), NS_CaseSensitive)) {
1036       while (IPDBEnumChildren<PDBSymbol>::ChildTypePtr child =
1037                  children_enum->getNext()) {
1038         if (clang::DeclContext *child_context =
1039                 GetDeclContextForSymbol(*child)) {
1040           // Note that `GetDeclContextForSymbol' retrieves
1041           // a declaration context for functions and types only,
1042           // so if we are here then `child_context' is guaranteed
1043           // a function or a type declaration context.
1044           has_type_or_function_parent = true;
1045           curr_context = child_context;
1046         }
1047       }
1048     }
1049 
1050     // If there were no functions or types above then retrieve a namespace with
1051     // the current context's name. There can be no namespaces inside a function
1052     // or a type. We check it to avoid fake namespaces such as `__l2':
1053     // `N0::N1::CClass::PrivateFunc::__l2::InnerFuncStruct'
1054     if (!has_type_or_function_parent) {
1055       std::string namespace_name = std::string(specs[i].GetBaseName());
1056       const char *namespace_name_c_str =
1057           IsAnonymousNamespaceName(namespace_name) ? nullptr
1058                                                    : namespace_name.data();
1059       clang::NamespaceDecl *namespace_decl =
1060           m_ast.GetUniqueNamespaceDeclaration(
1061               namespace_name_c_str, curr_context, OptionalClangModuleID());
1062 
1063       m_parent_to_namespaces[curr_context].insert(namespace_decl);
1064       m_namespaces.insert(namespace_decl);
1065 
1066       curr_context = namespace_decl;
1067     }
1068   }
1069 
1070   return curr_context;
1071 }
1072 
1073 void PDBASTParser::ParseDeclsForDeclContext(
1074     const clang::DeclContext *decl_context) {
1075   auto symbol_file = static_cast<SymbolFilePDB *>(m_ast.GetSymbolFile());
1076   if (!symbol_file)
1077     return;
1078 
1079   IPDBSession &session = symbol_file->GetPDBSession();
1080   auto symbol_up =
1081       session.getSymbolById(m_decl_context_to_uid.lookup(decl_context));
1082   auto global_up = session.getGlobalScope();
1083 
1084   PDBSymbol *symbol;
1085   if (symbol_up)
1086     symbol = symbol_up.get();
1087   else if (global_up)
1088     symbol = global_up.get();
1089   else
1090     return;
1091 
1092   if (auto children = symbol->findAllChildren())
1093     while (auto child = children->getNext())
1094       GetDeclForSymbol(*child);
1095 }
1096 
1097 clang::NamespaceDecl *
1098 PDBASTParser::FindNamespaceDecl(const clang::DeclContext *parent,
1099                                 llvm::StringRef name) {
1100   NamespacesSet *set;
1101   if (parent) {
1102     auto pit = m_parent_to_namespaces.find(parent);
1103     if (pit == m_parent_to_namespaces.end())
1104       return nullptr;
1105 
1106     set = &pit->second;
1107   } else {
1108     set = &m_namespaces;
1109   }
1110   assert(set);
1111 
1112   for (clang::NamespaceDecl *namespace_decl : *set)
1113     if (namespace_decl->getName().equals(name))
1114       return namespace_decl;
1115 
1116   for (clang::NamespaceDecl *namespace_decl : *set)
1117     if (namespace_decl->isAnonymousNamespace())
1118       return FindNamespaceDecl(namespace_decl, name);
1119 
1120   return nullptr;
1121 }
1122 
1123 bool PDBASTParser::AddEnumValue(CompilerType enum_type,
1124                                 const PDBSymbolData &enum_value) {
1125   Declaration decl;
1126   Variant v = enum_value.getValue();
1127   std::string name =
1128       std::string(MSVCUndecoratedNameParser::DropScope(enum_value.getName()));
1129   int64_t raw_value;
1130   switch (v.Type) {
1131   case PDB_VariantType::Int8:
1132     raw_value = v.Value.Int8;
1133     break;
1134   case PDB_VariantType::Int16:
1135     raw_value = v.Value.Int16;
1136     break;
1137   case PDB_VariantType::Int32:
1138     raw_value = v.Value.Int32;
1139     break;
1140   case PDB_VariantType::Int64:
1141     raw_value = v.Value.Int64;
1142     break;
1143   case PDB_VariantType::UInt8:
1144     raw_value = v.Value.UInt8;
1145     break;
1146   case PDB_VariantType::UInt16:
1147     raw_value = v.Value.UInt16;
1148     break;
1149   case PDB_VariantType::UInt32:
1150     raw_value = v.Value.UInt32;
1151     break;
1152   case PDB_VariantType::UInt64:
1153     raw_value = v.Value.UInt64;
1154     break;
1155   default:
1156     return false;
1157   }
1158   CompilerType underlying_type = m_ast.GetEnumerationIntegerType(enum_type);
1159   uint32_t byte_size = m_ast.getASTContext().getTypeSize(
1160       ClangUtil::GetQualType(underlying_type));
1161   auto enum_constant_decl = m_ast.AddEnumerationValueToEnumerationType(
1162       enum_type, decl, name.c_str(), raw_value, byte_size * 8);
1163   if (!enum_constant_decl)
1164     return false;
1165 
1166   m_uid_to_decl[enum_value.getSymIndexId()] = enum_constant_decl;
1167 
1168   return true;
1169 }
1170 
1171 bool PDBASTParser::CompleteTypeFromUDT(
1172     lldb_private::SymbolFile &symbol_file,
1173     lldb_private::CompilerType &compiler_type,
1174     llvm::pdb::PDBSymbolTypeUDT &udt) {
1175   ClangASTImporter::LayoutInfo layout_info;
1176   layout_info.bit_size = udt.getLength() * 8;
1177 
1178   auto nested_enums = udt.findAllChildren<PDBSymbolTypeUDT>();
1179   if (nested_enums)
1180     while (auto nested = nested_enums->getNext())
1181       symbol_file.ResolveTypeUID(nested->getSymIndexId());
1182 
1183   auto bases_enum = udt.findAllChildren<PDBSymbolTypeBaseClass>();
1184   if (bases_enum)
1185     AddRecordBases(symbol_file, compiler_type,
1186                    TranslateUdtKind(udt.getUdtKind()), *bases_enum,
1187                    layout_info);
1188 
1189   auto members_enum = udt.findAllChildren<PDBSymbolData>();
1190   if (members_enum)
1191     AddRecordMembers(symbol_file, compiler_type, *members_enum, layout_info);
1192 
1193   auto methods_enum = udt.findAllChildren<PDBSymbolFunc>();
1194   if (methods_enum)
1195     AddRecordMethods(symbol_file, compiler_type, *methods_enum);
1196 
1197   m_ast.AddMethodOverridesForCXXRecordType(compiler_type.GetOpaqueQualType());
1198   TypeSystemClang::BuildIndirectFields(compiler_type);
1199   TypeSystemClang::CompleteTagDeclarationDefinition(compiler_type);
1200 
1201   clang::CXXRecordDecl *record_decl =
1202       m_ast.GetAsCXXRecordDecl(compiler_type.GetOpaqueQualType());
1203   if (!record_decl)
1204     return static_cast<bool>(compiler_type);
1205 
1206   GetClangASTImporter().SetRecordLayout(record_decl, layout_info);
1207 
1208   return static_cast<bool>(compiler_type);
1209 }
1210 
1211 void PDBASTParser::AddRecordMembers(
1212     lldb_private::SymbolFile &symbol_file,
1213     lldb_private::CompilerType &record_type,
1214     PDBDataSymbolEnumerator &members_enum,
1215     lldb_private::ClangASTImporter::LayoutInfo &layout_info) {
1216   while (auto member = members_enum.getNext()) {
1217     if (member->isCompilerGenerated())
1218       continue;
1219 
1220     auto member_name = member->getName();
1221 
1222     auto member_type = symbol_file.ResolveTypeUID(member->getTypeId());
1223     if (!member_type)
1224       continue;
1225 
1226     auto member_comp_type = member_type->GetLayoutCompilerType();
1227     if (!member_comp_type.GetCompleteType()) {
1228       symbol_file.GetObjectFile()->GetModule()->ReportError(
1229           ":: Class '%s' has a member '%s' of type '%s' "
1230           "which does not have a complete definition.",
1231           record_type.GetTypeName().GetCString(), member_name.c_str(),
1232           member_comp_type.GetTypeName().GetCString());
1233       if (TypeSystemClang::StartTagDeclarationDefinition(member_comp_type))
1234         TypeSystemClang::CompleteTagDeclarationDefinition(member_comp_type);
1235     }
1236 
1237     auto access = TranslateMemberAccess(member->getAccess());
1238 
1239     switch (member->getDataKind()) {
1240     case PDB_DataKind::Member: {
1241       auto location_type = member->getLocationType();
1242 
1243       auto bit_size = member->getLength();
1244       if (location_type == PDB_LocType::ThisRel)
1245         bit_size *= 8;
1246 
1247       auto decl = TypeSystemClang::AddFieldToRecordType(
1248           record_type, member_name.c_str(), member_comp_type, access, bit_size);
1249       if (!decl)
1250         continue;
1251 
1252       m_uid_to_decl[member->getSymIndexId()] = decl;
1253 
1254       auto offset = member->getOffset() * 8;
1255       if (location_type == PDB_LocType::BitField)
1256         offset += member->getBitPosition();
1257 
1258       layout_info.field_offsets.insert(std::make_pair(decl, offset));
1259 
1260       break;
1261     }
1262     case PDB_DataKind::StaticMember: {
1263       auto decl = TypeSystemClang::AddVariableToRecordType(
1264           record_type, member_name.c_str(), member_comp_type, access);
1265       if (!decl)
1266         continue;
1267 
1268       // Static constant members may be a const[expr] declaration.
1269       // Query the symbol's value as the variable initializer if valid.
1270       if (member_comp_type.IsConst()) {
1271         auto value = member->getValue();
1272         clang::QualType qual_type = decl->getType();
1273         unsigned type_width = m_ast.getASTContext().getIntWidth(qual_type);
1274         unsigned constant_width = value.getBitWidth();
1275 
1276         if (qual_type->isIntegralOrEnumerationType()) {
1277           if (type_width >= constant_width) {
1278             TypeSystemClang::SetIntegerInitializerForVariable(
1279                 decl, value.toAPSInt().extOrTrunc(type_width));
1280           } else {
1281             LLDB_LOG(GetLogIfAllCategoriesSet(LIBLLDB_LOG_AST),
1282                      "Class '{0}' has a member '{1}' of type '{2}' ({3} bits) "
1283                      "which resolves to a wider constant value ({4} bits). "
1284                      "Ignoring constant.",
1285                      record_type.GetTypeName(), member_name,
1286                      member_comp_type.GetTypeName(), type_width,
1287                      constant_width);
1288           }
1289         } else {
1290           switch (member_comp_type.GetBasicTypeEnumeration()) {
1291           case lldb::eBasicTypeFloat:
1292           case lldb::eBasicTypeDouble:
1293           case lldb::eBasicTypeLongDouble:
1294             if (type_width == constant_width) {
1295               TypeSystemClang::SetFloatingInitializerForVariable(
1296                   decl, value.toAPFloat());
1297               decl->setConstexpr(true);
1298             } else {
1299               LLDB_LOG(GetLogIfAllCategoriesSet(LIBLLDB_LOG_AST),
1300                        "Class '{0}' has a member '{1}' of type '{2}' ({3} "
1301                        "bits) which resolves to a constant value of mismatched "
1302                        "width ({4} bits). Ignoring constant.",
1303                        record_type.GetTypeName(), member_name,
1304                        member_comp_type.GetTypeName(), type_width,
1305                        constant_width);
1306             }
1307             break;
1308           default:
1309             break;
1310           }
1311         }
1312       }
1313 
1314       m_uid_to_decl[member->getSymIndexId()] = decl;
1315 
1316       break;
1317     }
1318     default:
1319       llvm_unreachable("unsupported PDB data kind");
1320     }
1321   }
1322 }
1323 
1324 void PDBASTParser::AddRecordBases(
1325     lldb_private::SymbolFile &symbol_file,
1326     lldb_private::CompilerType &record_type, int record_kind,
1327     PDBBaseClassSymbolEnumerator &bases_enum,
1328     lldb_private::ClangASTImporter::LayoutInfo &layout_info) const {
1329   std::vector<std::unique_ptr<clang::CXXBaseSpecifier>> base_classes;
1330 
1331   while (auto base = bases_enum.getNext()) {
1332     auto base_type = symbol_file.ResolveTypeUID(base->getTypeId());
1333     if (!base_type)
1334       continue;
1335 
1336     auto base_comp_type = base_type->GetFullCompilerType();
1337     if (!base_comp_type.GetCompleteType()) {
1338       symbol_file.GetObjectFile()->GetModule()->ReportError(
1339           ":: Class '%s' has a base class '%s' "
1340           "which does not have a complete definition.",
1341           record_type.GetTypeName().GetCString(),
1342           base_comp_type.GetTypeName().GetCString());
1343       if (TypeSystemClang::StartTagDeclarationDefinition(base_comp_type))
1344         TypeSystemClang::CompleteTagDeclarationDefinition(base_comp_type);
1345     }
1346 
1347     auto access = TranslateMemberAccess(base->getAccess());
1348 
1349     auto is_virtual = base->isVirtualBaseClass();
1350 
1351     std::unique_ptr<clang::CXXBaseSpecifier> base_spec =
1352         m_ast.CreateBaseClassSpecifier(base_comp_type.GetOpaqueQualType(),
1353                                        access, is_virtual,
1354                                        record_kind == clang::TTK_Class);
1355     lldbassert(base_spec);
1356 
1357     base_classes.push_back(std::move(base_spec));
1358 
1359     if (is_virtual)
1360       continue;
1361 
1362     auto decl = m_ast.GetAsCXXRecordDecl(base_comp_type.GetOpaqueQualType());
1363     if (!decl)
1364       continue;
1365 
1366     auto offset = clang::CharUnits::fromQuantity(base->getOffset());
1367     layout_info.base_offsets.insert(std::make_pair(decl, offset));
1368   }
1369 
1370   m_ast.TransferBaseClasses(record_type.GetOpaqueQualType(),
1371                             std::move(base_classes));
1372 }
1373 
1374 void PDBASTParser::AddRecordMethods(lldb_private::SymbolFile &symbol_file,
1375                                     lldb_private::CompilerType &record_type,
1376                                     PDBFuncSymbolEnumerator &methods_enum) {
1377   while (std::unique_ptr<PDBSymbolFunc> method = methods_enum.getNext())
1378     if (clang::CXXMethodDecl *decl =
1379             AddRecordMethod(symbol_file, record_type, *method))
1380       m_uid_to_decl[method->getSymIndexId()] = decl;
1381 }
1382 
1383 clang::CXXMethodDecl *
1384 PDBASTParser::AddRecordMethod(lldb_private::SymbolFile &symbol_file,
1385                               lldb_private::CompilerType &record_type,
1386                               const llvm::pdb::PDBSymbolFunc &method) const {
1387   std::string name =
1388       std::string(MSVCUndecoratedNameParser::DropScope(method.getName()));
1389 
1390   Type *method_type = symbol_file.ResolveTypeUID(method.getSymIndexId());
1391   // MSVC specific __vecDelDtor.
1392   if (!method_type)
1393     return nullptr;
1394 
1395   CompilerType method_comp_type = method_type->GetFullCompilerType();
1396   if (!method_comp_type.GetCompleteType()) {
1397     symbol_file.GetObjectFile()->GetModule()->ReportError(
1398         ":: Class '%s' has a method '%s' whose type cannot be completed.",
1399         record_type.GetTypeName().GetCString(),
1400         method_comp_type.GetTypeName().GetCString());
1401     if (TypeSystemClang::StartTagDeclarationDefinition(method_comp_type))
1402       TypeSystemClang::CompleteTagDeclarationDefinition(method_comp_type);
1403   }
1404 
1405   AccessType access = TranslateMemberAccess(method.getAccess());
1406   if (access == eAccessNone)
1407     access = eAccessPublic;
1408 
1409   // TODO: get mangled name for the method.
1410   return m_ast.AddMethodToCXXRecordType(
1411       record_type.GetOpaqueQualType(), name.c_str(),
1412       /*mangled_name*/ nullptr, method_comp_type, access, method.isVirtual(),
1413       method.isStatic(), method.hasInlineAttribute(),
1414       /*is_explicit*/ false, // FIXME: Need this field in CodeView.
1415       /*is_attr_used*/ false,
1416       /*is_artificial*/ method.isCompilerGenerated());
1417 }
1418