1 //===-- SymbolFileDWARF.cpp ------------------------------------*- C++ -*-===//
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 "SymbolFileDWARF.h"
10 
11 #include "llvm/ADT/Optional.h"
12 #include "llvm/Support/Casting.h"
13 #include "llvm/Support/Threading.h"
14 
15 #include "lldb/Core/Module.h"
16 #include "lldb/Core/ModuleList.h"
17 #include "lldb/Core/ModuleSpec.h"
18 #include "lldb/Core/PluginManager.h"
19 #include "lldb/Core/Section.h"
20 #include "lldb/Core/StreamFile.h"
21 #include "lldb/Core/Value.h"
22 #include "lldb/Utility/ArchSpec.h"
23 #include "lldb/Utility/RegularExpression.h"
24 #include "lldb/Utility/Scalar.h"
25 #include "lldb/Utility/StreamString.h"
26 #include "lldb/Utility/Timer.h"
27 
28 #include "Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.h"
29 #include "Plugins/Language/CPlusPlus/CPlusPlusLanguage.h"
30 
31 #include "lldb/Host/FileSystem.h"
32 #include "lldb/Host/Host.h"
33 
34 #include "lldb/Interpreter/OptionValueFileSpecList.h"
35 #include "lldb/Interpreter/OptionValueProperties.h"
36 
37 #include "lldb/Symbol/Block.h"
38 #include "lldb/Symbol/ClangASTContext.h"
39 #include "lldb/Symbol/ClangUtil.h"
40 #include "lldb/Symbol/CompileUnit.h"
41 #include "lldb/Symbol/CompilerDecl.h"
42 #include "lldb/Symbol/CompilerDeclContext.h"
43 #include "lldb/Symbol/DebugMacros.h"
44 #include "lldb/Symbol/LineTable.h"
45 #include "lldb/Symbol/LocateSymbolFile.h"
46 #include "lldb/Symbol/ObjectFile.h"
47 #include "lldb/Symbol/SymbolFile.h"
48 #include "lldb/Symbol/TypeMap.h"
49 #include "lldb/Symbol/TypeSystem.h"
50 #include "lldb/Symbol/VariableList.h"
51 
52 #include "lldb/Target/Language.h"
53 #include "lldb/Target/Target.h"
54 
55 #include "AppleDWARFIndex.h"
56 #include "DWARFASTParser.h"
57 #include "DWARFASTParserClang.h"
58 #include "DWARFCompileUnit.h"
59 #include "DWARFDebugAbbrev.h"
60 #include "DWARFDebugAranges.h"
61 #include "DWARFDebugInfo.h"
62 #include "DWARFDebugMacro.h"
63 #include "DWARFDebugRanges.h"
64 #include "DWARFDeclContext.h"
65 #include "DWARFFormValue.h"
66 #include "DWARFTypeUnit.h"
67 #include "DWARFUnit.h"
68 #include "DebugNamesDWARFIndex.h"
69 #include "LogChannelDWARF.h"
70 #include "ManualDWARFIndex.h"
71 #include "SymbolFileDWARFDebugMap.h"
72 #include "SymbolFileDWARFDwo.h"
73 #include "SymbolFileDWARFDwp.h"
74 
75 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
76 #include "llvm/Support/FileSystem.h"
77 
78 #include <algorithm>
79 #include <map>
80 #include <memory>
81 
82 #include <ctype.h>
83 #include <string.h>
84 
85 //#define ENABLE_DEBUG_PRINTF // COMMENT OUT THIS LINE PRIOR TO CHECKIN
86 
87 #ifdef ENABLE_DEBUG_PRINTF
88 #include <stdio.h>
89 #define DEBUG_PRINTF(fmt, ...) printf(fmt, __VA_ARGS__)
90 #else
91 #define DEBUG_PRINTF(fmt, ...)
92 #endif
93 
94 using namespace lldb;
95 using namespace lldb_private;
96 
97 // static inline bool
98 // child_requires_parent_class_union_or_struct_to_be_completed (dw_tag_t tag)
99 //{
100 //    switch (tag)
101 //    {
102 //    default:
103 //        break;
104 //    case DW_TAG_subprogram:
105 //    case DW_TAG_inlined_subroutine:
106 //    case DW_TAG_class_type:
107 //    case DW_TAG_structure_type:
108 //    case DW_TAG_union_type:
109 //        return true;
110 //    }
111 //    return false;
112 //}
113 //
114 
115 namespace {
116 
117 #define LLDB_PROPERTIES_symbolfiledwarf
118 #include "SymbolFileDWARFProperties.inc"
119 
120 enum {
121 #define LLDB_PROPERTIES_symbolfiledwarf
122 #include "SymbolFileDWARFPropertiesEnum.inc"
123 };
124 
125 class PluginProperties : public Properties {
126 public:
127   static ConstString GetSettingName() {
128     return SymbolFileDWARF::GetPluginNameStatic();
129   }
130 
131   PluginProperties() {
132     m_collection_sp = std::make_shared<OptionValueProperties>(GetSettingName());
133     m_collection_sp->Initialize(g_symbolfiledwarf_properties);
134   }
135 
136   FileSpecList GetSymLinkPaths() {
137     const OptionValueFileSpecList *option_value =
138         m_collection_sp->GetPropertyAtIndexAsOptionValueFileSpecList(
139             nullptr, true, ePropertySymLinkPaths);
140     assert(option_value);
141     return option_value->GetCurrentValue();
142   }
143 
144   bool IgnoreFileIndexes() const {
145     return m_collection_sp->GetPropertyAtIndexAsBoolean(
146         nullptr, ePropertyIgnoreIndexes, false);
147   }
148 };
149 
150 typedef std::shared_ptr<PluginProperties> SymbolFileDWARFPropertiesSP;
151 
152 static const SymbolFileDWARFPropertiesSP &GetGlobalPluginProperties() {
153   static const auto g_settings_sp(std::make_shared<PluginProperties>());
154   return g_settings_sp;
155 }
156 
157 } // namespace
158 
159 static const llvm::DWARFDebugLine::LineTable *
160 ParseLLVMLineTable(lldb_private::DWARFContext &context,
161                    llvm::DWARFDebugLine &line, dw_offset_t line_offset,
162                    dw_offset_t unit_offset) {
163   Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO);
164 
165   llvm::DWARFDataExtractor data = context.getOrLoadLineData().GetAsLLVM();
166   llvm::DWARFContext &ctx = context.GetAsLLVM();
167   llvm::Expected<const llvm::DWARFDebugLine::LineTable *> line_table =
168       line.getOrParseLineTable(
169           data, line_offset, ctx, nullptr, [&](llvm::Error e) {
170             LLDB_LOG_ERROR(log, std::move(e),
171                            "SymbolFileDWARF::ParseLineTable failed to parse");
172           });
173 
174   if (!line_table) {
175     LLDB_LOG_ERROR(log, line_table.takeError(),
176                    "SymbolFileDWARF::ParseLineTable failed to parse");
177     return nullptr;
178   }
179   return *line_table;
180 }
181 
182 static llvm::Optional<std::string>
183 GetFileByIndex(const llvm::DWARFDebugLine::Prologue &prologue, size_t idx,
184                llvm::StringRef compile_dir, FileSpec::Style style) {
185   // Try to get an absolute path first.
186   std::string abs_path;
187   auto absolute = llvm::DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath;
188   if (prologue.getFileNameByIndex(idx, compile_dir, absolute, abs_path, style))
189     return std::move(abs_path);
190 
191   // Otherwise ask for a relative path.
192   std::string rel_path;
193   auto relative = llvm::DILineInfoSpecifier::FileLineInfoKind::Default;
194   if (!prologue.getFileNameByIndex(idx, compile_dir, relative, rel_path, style))
195     return {};
196   return std::move(rel_path);
197 }
198 
199 static FileSpecList ParseSupportFilesFromPrologue(
200     const lldb::ModuleSP &module,
201     const llvm::DWARFDebugLine::Prologue &prologue, FileSpec::Style style,
202     llvm::StringRef compile_dir = {}, FileSpec first_file = {}) {
203   FileSpecList support_files;
204   support_files.Append(first_file);
205 
206   const size_t number_of_files = prologue.FileNames.size();
207   for (size_t idx = 1; idx <= number_of_files; ++idx) {
208     std::string remapped_file;
209     if (auto file_path = GetFileByIndex(prologue, idx, compile_dir, style))
210       if (!module->RemapSourceFile(llvm::StringRef(*file_path), remapped_file))
211         remapped_file = std::move(*file_path);
212 
213     // Unconditionally add an entry, so the indices match up.
214     support_files.EmplaceBack(remapped_file, style);
215   }
216 
217   return support_files;
218 }
219 
220 FileSpecList SymbolFileDWARF::GetSymlinkPaths() {
221   return GetGlobalPluginProperties()->GetSymLinkPaths();
222 }
223 
224 void SymbolFileDWARF::Initialize() {
225   LogChannelDWARF::Initialize();
226   PluginManager::RegisterPlugin(GetPluginNameStatic(),
227                                 GetPluginDescriptionStatic(), CreateInstance,
228                                 DebuggerInitialize);
229 }
230 
231 void SymbolFileDWARF::DebuggerInitialize(Debugger &debugger) {
232   if (!PluginManager::GetSettingForSymbolFilePlugin(
233           debugger, PluginProperties::GetSettingName())) {
234     const bool is_global_setting = true;
235     PluginManager::CreateSettingForSymbolFilePlugin(
236         debugger, GetGlobalPluginProperties()->GetValueProperties(),
237         ConstString("Properties for the dwarf symbol-file plug-in."),
238         is_global_setting);
239   }
240 }
241 
242 void SymbolFileDWARF::Terminate() {
243   PluginManager::UnregisterPlugin(CreateInstance);
244   LogChannelDWARF::Terminate();
245 }
246 
247 lldb_private::ConstString SymbolFileDWARF::GetPluginNameStatic() {
248   static ConstString g_name("dwarf");
249   return g_name;
250 }
251 
252 const char *SymbolFileDWARF::GetPluginDescriptionStatic() {
253   return "DWARF and DWARF3 debug symbol file reader.";
254 }
255 
256 SymbolFile *SymbolFileDWARF::CreateInstance(ObjectFileSP objfile_sp) {
257   return new SymbolFileDWARF(std::move(objfile_sp),
258                              /*dwo_section_list*/ nullptr);
259 }
260 
261 TypeList &SymbolFileDWARF::GetTypeList() {
262   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
263   if (SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile())
264     return debug_map_symfile->GetTypeList();
265   return SymbolFile::GetTypeList();
266 }
267 void SymbolFileDWARF::GetTypes(const DWARFDIE &die, dw_offset_t min_die_offset,
268                                dw_offset_t max_die_offset, uint32_t type_mask,
269                                TypeSet &type_set) {
270   if (die) {
271     const dw_offset_t die_offset = die.GetOffset();
272 
273     if (die_offset >= max_die_offset)
274       return;
275 
276     if (die_offset >= min_die_offset) {
277       const dw_tag_t tag = die.Tag();
278 
279       bool add_type = false;
280 
281       switch (tag) {
282       case DW_TAG_array_type:
283         add_type = (type_mask & eTypeClassArray) != 0;
284         break;
285       case DW_TAG_unspecified_type:
286       case DW_TAG_base_type:
287         add_type = (type_mask & eTypeClassBuiltin) != 0;
288         break;
289       case DW_TAG_class_type:
290         add_type = (type_mask & eTypeClassClass) != 0;
291         break;
292       case DW_TAG_structure_type:
293         add_type = (type_mask & eTypeClassStruct) != 0;
294         break;
295       case DW_TAG_union_type:
296         add_type = (type_mask & eTypeClassUnion) != 0;
297         break;
298       case DW_TAG_enumeration_type:
299         add_type = (type_mask & eTypeClassEnumeration) != 0;
300         break;
301       case DW_TAG_subroutine_type:
302       case DW_TAG_subprogram:
303       case DW_TAG_inlined_subroutine:
304         add_type = (type_mask & eTypeClassFunction) != 0;
305         break;
306       case DW_TAG_pointer_type:
307         add_type = (type_mask & eTypeClassPointer) != 0;
308         break;
309       case DW_TAG_rvalue_reference_type:
310       case DW_TAG_reference_type:
311         add_type = (type_mask & eTypeClassReference) != 0;
312         break;
313       case DW_TAG_typedef:
314         add_type = (type_mask & eTypeClassTypedef) != 0;
315         break;
316       case DW_TAG_ptr_to_member_type:
317         add_type = (type_mask & eTypeClassMemberPointer) != 0;
318         break;
319       default:
320         break;
321       }
322 
323       if (add_type) {
324         const bool assert_not_being_parsed = true;
325         Type *type = ResolveTypeUID(die, assert_not_being_parsed);
326         if (type) {
327           if (type_set.find(type) == type_set.end())
328             type_set.insert(type);
329         }
330       }
331     }
332 
333     for (DWARFDIE child_die = die.GetFirstChild(); child_die.IsValid();
334          child_die = child_die.GetSibling()) {
335       GetTypes(child_die, min_die_offset, max_die_offset, type_mask, type_set);
336     }
337   }
338 }
339 
340 void SymbolFileDWARF::GetTypes(SymbolContextScope *sc_scope,
341                                TypeClass type_mask, TypeList &type_list)
342 
343 {
344   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
345   TypeSet type_set;
346 
347   CompileUnit *comp_unit = nullptr;
348   DWARFUnit *dwarf_cu = nullptr;
349   if (sc_scope)
350     comp_unit = sc_scope->CalculateSymbolContextCompileUnit();
351 
352   if (comp_unit) {
353     dwarf_cu = GetDWARFCompileUnit(comp_unit);
354     if (!dwarf_cu)
355       return;
356     GetTypes(dwarf_cu->DIE(), dwarf_cu->GetOffset(),
357              dwarf_cu->GetNextUnitOffset(), type_mask, type_set);
358   } else {
359     DWARFDebugInfo *info = DebugInfo();
360     if (info) {
361       const size_t num_cus = info->GetNumUnits();
362       for (size_t cu_idx = 0; cu_idx < num_cus; ++cu_idx) {
363         dwarf_cu = info->GetUnitAtIndex(cu_idx);
364         if (dwarf_cu) {
365           GetTypes(dwarf_cu->DIE(), 0, UINT32_MAX, type_mask, type_set);
366         }
367       }
368     }
369   }
370 
371   std::set<CompilerType> compiler_type_set;
372   for (Type *type : type_set) {
373     CompilerType compiler_type = type->GetForwardCompilerType();
374     if (compiler_type_set.find(compiler_type) == compiler_type_set.end()) {
375       compiler_type_set.insert(compiler_type);
376       type_list.Insert(type->shared_from_this());
377     }
378   }
379 }
380 
381 // Gets the first parent that is a lexical block, function or inlined
382 // subroutine, or compile unit.
383 DWARFDIE
384 SymbolFileDWARF::GetParentSymbolContextDIE(const DWARFDIE &child_die) {
385   DWARFDIE die;
386   for (die = child_die.GetParent(); die; die = die.GetParent()) {
387     dw_tag_t tag = die.Tag();
388 
389     switch (tag) {
390     case DW_TAG_compile_unit:
391     case DW_TAG_partial_unit:
392     case DW_TAG_subprogram:
393     case DW_TAG_inlined_subroutine:
394     case DW_TAG_lexical_block:
395       return die;
396     default:
397       break;
398     }
399   }
400   return DWARFDIE();
401 }
402 
403 SymbolFileDWARF::SymbolFileDWARF(ObjectFileSP objfile_sp,
404                                  SectionList *dwo_section_list)
405     : SymbolFile(std::move(objfile_sp)),
406       UserID(0x7fffffff00000000), // Used by SymbolFileDWARFDebugMap to
407                                   // when this class parses .o files to
408                                   // contain the .o file index/ID
409       m_debug_map_module_wp(), m_debug_map_symfile(nullptr),
410       m_context(m_objfile_sp->GetModule()->GetSectionList(), dwo_section_list),
411       m_data_debug_loc(), m_abbr(), m_info(), m_fetched_external_modules(false),
412       m_supports_DW_AT_APPLE_objc_complete_type(eLazyBoolCalculate),
413       m_unique_ast_type_map() {}
414 
415 SymbolFileDWARF::~SymbolFileDWARF() {}
416 
417 static ConstString GetDWARFMachOSegmentName() {
418   static ConstString g_dwarf_section_name("__DWARF");
419   return g_dwarf_section_name;
420 }
421 
422 UniqueDWARFASTTypeMap &SymbolFileDWARF::GetUniqueDWARFASTTypeMap() {
423   SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
424   if (debug_map_symfile)
425     return debug_map_symfile->GetUniqueDWARFASTTypeMap();
426   else
427     return m_unique_ast_type_map;
428 }
429 
430 llvm::Expected<TypeSystem &>
431 SymbolFileDWARF::GetTypeSystemForLanguage(LanguageType language) {
432   if (SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile())
433     return debug_map_symfile->GetTypeSystemForLanguage(language);
434 
435   auto type_system_or_err =
436       m_objfile_sp->GetModule()->GetTypeSystemForLanguage(language);
437   if (type_system_or_err) {
438     type_system_or_err->SetSymbolFile(this);
439   }
440   return type_system_or_err;
441 }
442 
443 void SymbolFileDWARF::InitializeObject() {
444   Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO);
445 
446   if (!GetGlobalPluginProperties()->IgnoreFileIndexes()) {
447     DWARFDataExtractor apple_names, apple_namespaces, apple_types, apple_objc;
448     LoadSectionData(eSectionTypeDWARFAppleNames, apple_names);
449     LoadSectionData(eSectionTypeDWARFAppleNamespaces, apple_namespaces);
450     LoadSectionData(eSectionTypeDWARFAppleTypes, apple_types);
451     LoadSectionData(eSectionTypeDWARFAppleObjC, apple_objc);
452 
453     m_index = AppleDWARFIndex::Create(
454         *GetObjectFile()->GetModule(), apple_names, apple_namespaces,
455         apple_types, apple_objc, m_context.getOrLoadStrData());
456 
457     if (m_index)
458       return;
459 
460     DWARFDataExtractor debug_names;
461     LoadSectionData(eSectionTypeDWARFDebugNames, debug_names);
462     if (debug_names.GetByteSize() > 0) {
463       llvm::Expected<std::unique_ptr<DebugNamesDWARFIndex>> index_or =
464           DebugNamesDWARFIndex::Create(
465               *GetObjectFile()->GetModule(), debug_names,
466               m_context.getOrLoadStrData(), DebugInfo());
467       if (index_or) {
468         m_index = std::move(*index_or);
469         return;
470       }
471       LLDB_LOG_ERROR(log, index_or.takeError(),
472                      "Unable to read .debug_names data: {0}");
473     }
474   }
475 
476   m_index = std::make_unique<ManualDWARFIndex>(*GetObjectFile()->GetModule(),
477                                                 DebugInfo());
478 }
479 
480 bool SymbolFileDWARF::SupportedVersion(uint16_t version) {
481   return version >= 2 && version <= 5;
482 }
483 
484 uint32_t SymbolFileDWARF::CalculateAbilities() {
485   uint32_t abilities = 0;
486   if (m_objfile_sp != nullptr) {
487     const Section *section = nullptr;
488     const SectionList *section_list = m_objfile_sp->GetSectionList();
489     if (section_list == nullptr)
490       return 0;
491 
492     uint64_t debug_abbrev_file_size = 0;
493     uint64_t debug_info_file_size = 0;
494     uint64_t debug_line_file_size = 0;
495 
496     section = section_list->FindSectionByName(GetDWARFMachOSegmentName()).get();
497 
498     if (section)
499       section_list = &section->GetChildren();
500 
501     section =
502         section_list->FindSectionByType(eSectionTypeDWARFDebugInfo, true).get();
503     if (section != nullptr) {
504       debug_info_file_size = section->GetFileSize();
505 
506       section =
507           section_list->FindSectionByType(eSectionTypeDWARFDebugAbbrev, true)
508               .get();
509       if (section)
510         debug_abbrev_file_size = section->GetFileSize();
511 
512       DWARFDebugAbbrev *abbrev = DebugAbbrev();
513       if (abbrev) {
514         std::set<dw_form_t> invalid_forms;
515         abbrev->GetUnsupportedForms(invalid_forms);
516         if (!invalid_forms.empty()) {
517           StreamString error;
518           error.Printf("unsupported DW_FORM value%s:",
519                        invalid_forms.size() > 1 ? "s" : "");
520           for (auto form : invalid_forms)
521             error.Printf(" %#x", form);
522           m_objfile_sp->GetModule()->ReportWarning(
523               "%s", error.GetString().str().c_str());
524           return 0;
525         }
526       }
527 
528       section =
529           section_list->FindSectionByType(eSectionTypeDWARFDebugLine, true)
530               .get();
531       if (section)
532         debug_line_file_size = section->GetFileSize();
533     } else {
534       const char *symfile_dir_cstr =
535           m_objfile_sp->GetFileSpec().GetDirectory().GetCString();
536       if (symfile_dir_cstr) {
537         if (strcasestr(symfile_dir_cstr, ".dsym")) {
538           if (m_objfile_sp->GetType() == ObjectFile::eTypeDebugInfo) {
539             // We have a dSYM file that didn't have a any debug info. If the
540             // string table has a size of 1, then it was made from an
541             // executable with no debug info, or from an executable that was
542             // stripped.
543             section =
544                 section_list->FindSectionByType(eSectionTypeDWARFDebugStr, true)
545                     .get();
546             if (section && section->GetFileSize() == 1) {
547               m_objfile_sp->GetModule()->ReportWarning(
548                   "empty dSYM file detected, dSYM was created with an "
549                   "executable with no debug info.");
550             }
551           }
552         }
553       }
554     }
555 
556     if (debug_abbrev_file_size > 0 && debug_info_file_size > 0)
557       abilities |= CompileUnits | Functions | Blocks | GlobalVariables |
558                    LocalVariables | VariableTypes;
559 
560     if (debug_line_file_size > 0)
561       abilities |= LineTables;
562   }
563   return abilities;
564 }
565 
566 const DWARFDataExtractor &
567 SymbolFileDWARF::GetCachedSectionData(lldb::SectionType sect_type,
568                                       DWARFDataSegment &data_segment) {
569   llvm::call_once(data_segment.m_flag, [this, sect_type, &data_segment] {
570     this->LoadSectionData(sect_type, std::ref(data_segment.m_data));
571   });
572   return data_segment.m_data;
573 }
574 
575 void SymbolFileDWARF::LoadSectionData(lldb::SectionType sect_type,
576                                       DWARFDataExtractor &data) {
577   ModuleSP module_sp(m_objfile_sp->GetModule());
578   const SectionList *section_list = module_sp->GetSectionList();
579   if (!section_list)
580     return;
581 
582   SectionSP section_sp(section_list->FindSectionByType(sect_type, true));
583   if (!section_sp)
584     return;
585 
586   data.Clear();
587   m_objfile_sp->ReadSectionData(section_sp.get(), data);
588 }
589 
590 const DWARFDataExtractor &SymbolFileDWARF::DebugLocData() {
591   const DWARFDataExtractor &debugLocData = get_debug_loc_data();
592   if (debugLocData.GetByteSize() > 0)
593     return debugLocData;
594   return get_debug_loclists_data();
595 }
596 
597 const DWARFDataExtractor &SymbolFileDWARF::get_debug_loc_data() {
598   return GetCachedSectionData(eSectionTypeDWARFDebugLoc, m_data_debug_loc);
599 }
600 
601 const DWARFDataExtractor &SymbolFileDWARF::get_debug_loclists_data() {
602   return GetCachedSectionData(eSectionTypeDWARFDebugLocLists,
603                               m_data_debug_loclists);
604 }
605 
606 DWARFDebugAbbrev *SymbolFileDWARF::DebugAbbrev() {
607   if (m_abbr)
608     return m_abbr.get();
609 
610   const DWARFDataExtractor &debug_abbrev_data = m_context.getOrLoadAbbrevData();
611   if (debug_abbrev_data.GetByteSize() == 0)
612     return nullptr;
613 
614   auto abbr = std::make_unique<DWARFDebugAbbrev>();
615   llvm::Error error = abbr->parse(debug_abbrev_data);
616   if (error) {
617     Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO);
618     LLDB_LOG_ERROR(log, std::move(error),
619                    "Unable to read .debug_abbrev section: {0}");
620     return nullptr;
621   }
622 
623   m_abbr = std::move(abbr);
624   return m_abbr.get();
625 }
626 
627 const DWARFDebugAbbrev *SymbolFileDWARF::DebugAbbrev() const {
628   return m_abbr.get();
629 }
630 
631 DWARFDebugInfo *SymbolFileDWARF::DebugInfo() {
632   if (m_info == nullptr) {
633     static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
634     Timer scoped_timer(func_cat, "%s this = %p", LLVM_PRETTY_FUNCTION,
635                        static_cast<void *>(this));
636     if (m_context.getOrLoadDebugInfoData().GetByteSize() > 0)
637       m_info = std::make_unique<DWARFDebugInfo>(*this, m_context);
638   }
639   return m_info.get();
640 }
641 
642 const DWARFDebugInfo *SymbolFileDWARF::DebugInfo() const {
643   return m_info.get();
644 }
645 
646 DWARFUnit *
647 SymbolFileDWARF::GetDWARFCompileUnit(lldb_private::CompileUnit *comp_unit) {
648   if (!comp_unit)
649     return nullptr;
650 
651   DWARFDebugInfo *info = DebugInfo();
652   if (info) {
653     // The compile unit ID is the index of the DWARF unit.
654     DWARFUnit *dwarf_cu = info->GetUnitAtIndex(comp_unit->GetID());
655     if (dwarf_cu && dwarf_cu->GetUserData() == nullptr)
656       dwarf_cu->SetUserData(comp_unit);
657     return dwarf_cu;
658   }
659   return nullptr;
660 }
661 
662 DWARFDebugRanges *SymbolFileDWARF::GetDebugRanges() {
663   if (!m_ranges) {
664     static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
665     Timer scoped_timer(func_cat, "%s this = %p", LLVM_PRETTY_FUNCTION,
666                        static_cast<void *>(this));
667 
668     if (m_context.getOrLoadRangesData().GetByteSize() > 0)
669       m_ranges.reset(new DWARFDebugRanges());
670 
671     if (m_ranges)
672       m_ranges->Extract(m_context);
673   }
674   return m_ranges.get();
675 }
676 
677 DWARFDebugRngLists *SymbolFileDWARF::GetDebugRngLists() {
678   if (!m_rnglists) {
679     static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
680     Timer scoped_timer(func_cat, "%s this = %p", LLVM_PRETTY_FUNCTION,
681                        static_cast<void *>(this));
682 
683     if (m_context.getOrLoadRngListsData().GetByteSize() > 0)
684       m_rnglists.reset(new DWARFDebugRngLists());
685 
686     if (m_rnglists)
687       m_rnglists->Extract(m_context);
688   }
689   return m_rnglists.get();
690 }
691 
692 lldb::CompUnitSP SymbolFileDWARF::ParseCompileUnit(DWARFCompileUnit &dwarf_cu) {
693   CompUnitSP cu_sp;
694   CompileUnit *comp_unit = (CompileUnit *)dwarf_cu.GetUserData();
695   if (comp_unit) {
696     // We already parsed this compile unit, had out a shared pointer to it
697     cu_sp = comp_unit->shared_from_this();
698   } else {
699     if (&dwarf_cu.GetSymbolFileDWARF() != this) {
700       return dwarf_cu.GetSymbolFileDWARF().ParseCompileUnit(dwarf_cu);
701     } else if (dwarf_cu.GetOffset() == 0 && GetDebugMapSymfile()) {
702       // Let the debug map create the compile unit
703       cu_sp = m_debug_map_symfile->GetCompileUnit(this);
704       dwarf_cu.SetUserData(cu_sp.get());
705     } else {
706       ModuleSP module_sp(m_objfile_sp->GetModule());
707       if (module_sp) {
708         const DWARFDIE cu_die = dwarf_cu.DIE();
709         if (cu_die) {
710           FileSpec cu_file_spec(cu_die.GetName(), dwarf_cu.GetPathStyle());
711           if (cu_file_spec) {
712             // If we have a full path to the compile unit, we don't need to
713             // resolve the file.  This can be expensive e.g. when the source
714             // files are NFS mounted.
715             cu_file_spec.MakeAbsolute(dwarf_cu.GetCompilationDirectory());
716 
717             std::string remapped_file;
718             if (module_sp->RemapSourceFile(cu_file_spec.GetPath(),
719                                            remapped_file))
720               cu_file_spec.SetFile(remapped_file, FileSpec::Style::native);
721           }
722 
723           LanguageType cu_language = DWARFUnit::LanguageTypeFromDWARF(
724               cu_die.GetAttributeValueAsUnsigned(DW_AT_language, 0));
725 
726           bool is_optimized = dwarf_cu.GetIsOptimized();
727           BuildCuTranslationTable();
728           cu_sp = std::make_shared<CompileUnit>(
729               module_sp, &dwarf_cu, cu_file_spec,
730               *GetDWARFUnitIndex(dwarf_cu.GetID()), cu_language,
731               is_optimized ? eLazyBoolYes : eLazyBoolNo);
732 
733           dwarf_cu.SetUserData(cu_sp.get());
734 
735           SetCompileUnitAtIndex(dwarf_cu.GetID(), cu_sp);
736         }
737       }
738     }
739   }
740   return cu_sp;
741 }
742 
743 void SymbolFileDWARF::BuildCuTranslationTable() {
744   if (!m_lldb_cu_to_dwarf_unit.empty())
745     return;
746 
747   DWARFDebugInfo *info = DebugInfo();
748   if (!info)
749     return;
750 
751   if (!info->ContainsTypeUnits()) {
752     // We can use a 1-to-1 mapping. No need to build a translation table.
753     return;
754   }
755   for (uint32_t i = 0, num = info->GetNumUnits(); i < num; ++i) {
756     if (auto *cu = llvm::dyn_cast<DWARFCompileUnit>(info->GetUnitAtIndex(i))) {
757       cu->SetID(m_lldb_cu_to_dwarf_unit.size());
758       m_lldb_cu_to_dwarf_unit.push_back(i);
759     }
760   }
761 }
762 
763 llvm::Optional<uint32_t> SymbolFileDWARF::GetDWARFUnitIndex(uint32_t cu_idx) {
764   BuildCuTranslationTable();
765   if (m_lldb_cu_to_dwarf_unit.empty())
766     return cu_idx;
767   if (cu_idx >= m_lldb_cu_to_dwarf_unit.size())
768     return llvm::None;
769   return m_lldb_cu_to_dwarf_unit[cu_idx];
770 }
771 
772 uint32_t SymbolFileDWARF::CalculateNumCompileUnits() {
773   DWARFDebugInfo *info = DebugInfo();
774   if (!info)
775     return 0;
776   BuildCuTranslationTable();
777   return m_lldb_cu_to_dwarf_unit.empty() ? info->GetNumUnits()
778                                          : m_lldb_cu_to_dwarf_unit.size();
779 }
780 
781 CompUnitSP SymbolFileDWARF::ParseCompileUnitAtIndex(uint32_t cu_idx) {
782   ASSERT_MODULE_LOCK(this);
783   DWARFDebugInfo *info = DebugInfo();
784   if (!info)
785     return {};
786 
787   if (llvm::Optional<uint32_t> dwarf_idx = GetDWARFUnitIndex(cu_idx)) {
788     if (auto *dwarf_cu = llvm::cast_or_null<DWARFCompileUnit>(
789             info->GetUnitAtIndex(*dwarf_idx)))
790       return ParseCompileUnit(*dwarf_cu);
791   }
792   return {};
793 }
794 
795 Function *SymbolFileDWARF::ParseFunction(CompileUnit &comp_unit,
796                                          const DWARFDIE &die) {
797   ASSERT_MODULE_LOCK(this);
798   if (!die.IsValid())
799     return nullptr;
800 
801   auto type_system_or_err =
802       GetTypeSystemForLanguage(die.GetCU()->GetLanguageType());
803   if (auto err = type_system_or_err.takeError()) {
804     LLDB_LOG_ERROR(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_SYMBOLS),
805                    std::move(err), "Unable to parse function");
806     return nullptr;
807   }
808   DWARFASTParser *dwarf_ast = type_system_or_err->GetDWARFParser();
809   if (!dwarf_ast)
810     return nullptr;
811 
812   return dwarf_ast->ParseFunctionFromDWARF(comp_unit, die);
813 }
814 
815 bool SymbolFileDWARF::FixupAddress(Address &addr) {
816   SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
817   if (debug_map_symfile) {
818     return debug_map_symfile->LinkOSOAddress(addr);
819   }
820   // This is a normal DWARF file, no address fixups need to happen
821   return true;
822 }
823 lldb::LanguageType SymbolFileDWARF::ParseLanguage(CompileUnit &comp_unit) {
824   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
825   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(&comp_unit);
826   if (dwarf_cu)
827     return dwarf_cu->GetLanguageType();
828   else
829     return eLanguageTypeUnknown;
830 }
831 
832 size_t SymbolFileDWARF::ParseFunctions(CompileUnit &comp_unit) {
833   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
834   Timer scoped_timer(func_cat, "SymbolFileDWARF::ParseFunctions");
835   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
836   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(&comp_unit);
837   if (!dwarf_cu)
838     return 0;
839 
840   size_t functions_added = 0;
841   std::vector<DWARFDIE> function_dies;
842   dwarf_cu->GetNonSkeletonUnit().AppendDIEsWithTag(DW_TAG_subprogram,
843                                                     function_dies);
844   for (const DWARFDIE &die : function_dies) {
845     if (comp_unit.FindFunctionByUID(die.GetID()))
846       continue;
847     if (ParseFunction(comp_unit, die))
848       ++functions_added;
849   }
850   // FixupTypes();
851   return functions_added;
852 }
853 
854 bool SymbolFileDWARF::ForEachExternalModule(
855     CompileUnit &comp_unit,
856     llvm::DenseSet<lldb_private::SymbolFile *> &visited_symbol_files,
857     llvm::function_ref<bool(Module &)> lambda) {
858   // Only visit each symbol file once.
859   if (!visited_symbol_files.insert(this).second)
860     return false;
861 
862   UpdateExternalModuleListIfNeeded();
863   for (auto &p : m_external_type_modules) {
864     ModuleSP module = p.second;
865     if (!module)
866       continue;
867 
868     // Invoke the action and potentially early-exit.
869     if (lambda(*module))
870       return true;
871 
872     for (std::size_t i = 0; i < module->GetNumCompileUnits(); ++i) {
873       auto cu = module->GetCompileUnitAtIndex(i);
874       bool early_exit = cu->ForEachExternalModule(visited_symbol_files, lambda);
875       if (early_exit)
876         return true;
877     }
878   }
879   return false;
880 }
881 
882 bool SymbolFileDWARF::ParseSupportFiles(CompileUnit &comp_unit,
883                                         FileSpecList &support_files) {
884   if (!comp_unit.GetLineTable())
885     ParseLineTable(comp_unit);
886   return true;
887 }
888 
889 FileSpec SymbolFileDWARF::GetFile(DWARFUnit &unit, size_t file_idx) {
890   if (auto *dwarf_cu = llvm::dyn_cast<DWARFCompileUnit>(&unit)) {
891     if (CompileUnit *lldb_cu = GetCompUnitForDWARFCompUnit(*dwarf_cu))
892       return lldb_cu->GetSupportFiles().GetFileSpecAtIndex(file_idx);
893     return FileSpec();
894   }
895 
896   auto &tu = llvm::cast<DWARFTypeUnit>(unit);
897   return GetTypeUnitSupportFiles(tu).GetFileSpecAtIndex(file_idx);
898 }
899 
900 const FileSpecList &
901 SymbolFileDWARF::GetTypeUnitSupportFiles(DWARFTypeUnit &tu) {
902   static FileSpecList empty_list;
903 
904   dw_offset_t offset = tu.GetLineTableOffset();
905   if (offset == DW_INVALID_OFFSET ||
906       offset == llvm::DenseMapInfo<dw_offset_t>::getEmptyKey() ||
907       offset == llvm::DenseMapInfo<dw_offset_t>::getTombstoneKey())
908     return empty_list;
909 
910   // Many type units can share a line table, so parse the support file list
911   // once, and cache it based on the offset field.
912   auto iter_bool = m_type_unit_support_files.try_emplace(offset);
913   FileSpecList &list = iter_bool.first->second;
914   if (iter_bool.second) {
915     uint64_t line_table_offset = offset;
916     llvm::DWARFDataExtractor data = m_context.getOrLoadLineData().GetAsLLVM();
917     llvm::DWARFContext &ctx = m_context.GetAsLLVM();
918     llvm::DWARFDebugLine::Prologue prologue;
919     llvm::Error error = prologue.parse(data, &line_table_offset, ctx);
920     if (error) {
921       Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO);
922       LLDB_LOG_ERROR(log, std::move(error),
923                      "SymbolFileDWARF::GetTypeUnitSupportFiles failed to parse "
924                      "the line table prologue");
925     } else {
926       list = ParseSupportFilesFromPrologue(GetObjectFile()->GetModule(),
927                                            prologue, tu.GetPathStyle());
928     }
929   }
930   return list;
931 }
932 
933 bool SymbolFileDWARF::ParseIsOptimized(CompileUnit &comp_unit) {
934   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
935   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(&comp_unit);
936   if (dwarf_cu)
937     return dwarf_cu->GetIsOptimized();
938   return false;
939 }
940 
941 bool SymbolFileDWARF::ParseImportedModules(
942     const lldb_private::SymbolContext &sc,
943     std::vector<SourceModule> &imported_modules) {
944   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
945   assert(sc.comp_unit);
946   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
947   if (!dwarf_cu)
948     return false;
949   if (!ClangModulesDeclVendor::LanguageSupportsClangModules(
950           sc.comp_unit->GetLanguage()))
951     return false;
952   UpdateExternalModuleListIfNeeded();
953 
954   const DWARFDIE die = dwarf_cu->DIE();
955   if (!die)
956     return false;
957 
958   for (DWARFDIE child_die = die.GetFirstChild(); child_die;
959        child_die = child_die.GetSibling()) {
960     if (child_die.Tag() != DW_TAG_imported_declaration)
961       continue;
962 
963     DWARFDIE module_die = child_die.GetReferencedDIE(DW_AT_import);
964     if (module_die.Tag() != DW_TAG_module)
965       continue;
966 
967     if (const char *name =
968             module_die.GetAttributeValueAsString(DW_AT_name, nullptr)) {
969       SourceModule module;
970       module.path.push_back(ConstString(name));
971 
972       DWARFDIE parent_die = module_die;
973       while ((parent_die = parent_die.GetParent())) {
974         if (parent_die.Tag() != DW_TAG_module)
975           break;
976         if (const char *name =
977                 parent_die.GetAttributeValueAsString(DW_AT_name, nullptr))
978           module.path.push_back(ConstString(name));
979       }
980       std::reverse(module.path.begin(), module.path.end());
981       if (const char *include_path = module_die.GetAttributeValueAsString(
982               DW_AT_LLVM_include_path, nullptr))
983         module.search_path = ConstString(include_path);
984       if (const char *sysroot = module_die.GetAttributeValueAsString(
985               DW_AT_LLVM_isysroot, nullptr))
986         module.sysroot = ConstString(sysroot);
987       imported_modules.push_back(module);
988     }
989   }
990   return true;
991 }
992 
993 bool SymbolFileDWARF::ParseLineTable(CompileUnit &comp_unit) {
994   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
995   if (comp_unit.GetLineTable() != nullptr)
996     return true;
997 
998   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(&comp_unit);
999   if (!dwarf_cu)
1000     return false;
1001 
1002   const DWARFBaseDIE dwarf_cu_die = dwarf_cu->GetUnitDIEOnly();
1003   if (!dwarf_cu_die)
1004     return false;
1005 
1006   const dw_offset_t cu_line_offset = dwarf_cu_die.GetAttributeValueAsUnsigned(
1007       DW_AT_stmt_list, DW_INVALID_OFFSET);
1008   if (cu_line_offset == DW_INVALID_OFFSET)
1009     return false;
1010 
1011   llvm::DWARFDebugLine line;
1012   const llvm::DWARFDebugLine::LineTable *line_table = ParseLLVMLineTable(
1013       m_context, line, cu_line_offset, dwarf_cu->GetOffset());
1014 
1015   if (!line_table)
1016     return false;
1017 
1018   // FIXME: Rather than parsing the whole line table and then copying it over
1019   // into LLDB, we should explore using a callback to populate the line table
1020   // while we parse to reduce memory usage.
1021   std::unique_ptr<LineTable> line_table_up =
1022       std::make_unique<LineTable>(&comp_unit);
1023   LineSequence *sequence = line_table_up->CreateLineSequenceContainer();
1024   for (auto &row : line_table->Rows) {
1025     line_table_up->AppendLineEntryToSequence(
1026         sequence, row.Address.Address, row.Line, row.Column, row.File,
1027         row.IsStmt, row.BasicBlock, row.PrologueEnd, row.EpilogueBegin,
1028         row.EndSequence);
1029     if (row.EndSequence) {
1030       line_table_up->InsertSequence(sequence);
1031       sequence = line_table_up->CreateLineSequenceContainer();
1032     }
1033   }
1034 
1035   if (SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile()) {
1036     // We have an object file that has a line table with addresses that are not
1037     // linked. We need to link the line table and convert the addresses that
1038     // are relative to the .o file into addresses for the main executable.
1039     comp_unit.SetLineTable(
1040         debug_map_symfile->LinkOSOLineTable(this, line_table_up.get()));
1041   } else {
1042     comp_unit.SetLineTable(line_table_up.release());
1043   }
1044 
1045   comp_unit.SetSupportFiles(ParseSupportFilesFromPrologue(
1046       comp_unit.GetModule(), line_table->Prologue, dwarf_cu->GetPathStyle(),
1047       dwarf_cu->GetCompilationDirectory().GetCString(), FileSpec(comp_unit)));
1048 
1049   return true;
1050 }
1051 
1052 lldb_private::DebugMacrosSP
1053 SymbolFileDWARF::ParseDebugMacros(lldb::offset_t *offset) {
1054   auto iter = m_debug_macros_map.find(*offset);
1055   if (iter != m_debug_macros_map.end())
1056     return iter->second;
1057 
1058   const DWARFDataExtractor &debug_macro_data = m_context.getOrLoadMacroData();
1059   if (debug_macro_data.GetByteSize() == 0)
1060     return DebugMacrosSP();
1061 
1062   lldb_private::DebugMacrosSP debug_macros_sp(new lldb_private::DebugMacros());
1063   m_debug_macros_map[*offset] = debug_macros_sp;
1064 
1065   const DWARFDebugMacroHeader &header =
1066       DWARFDebugMacroHeader::ParseHeader(debug_macro_data, offset);
1067   DWARFDebugMacroEntry::ReadMacroEntries(
1068       debug_macro_data, m_context.getOrLoadStrData(), header.OffsetIs64Bit(),
1069       offset, this, debug_macros_sp);
1070 
1071   return debug_macros_sp;
1072 }
1073 
1074 bool SymbolFileDWARF::ParseDebugMacros(CompileUnit &comp_unit) {
1075   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1076 
1077   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(&comp_unit);
1078   if (dwarf_cu == nullptr)
1079     return false;
1080 
1081   const DWARFBaseDIE dwarf_cu_die = dwarf_cu->GetUnitDIEOnly();
1082   if (!dwarf_cu_die)
1083     return false;
1084 
1085   lldb::offset_t sect_offset =
1086       dwarf_cu_die.GetAttributeValueAsUnsigned(DW_AT_macros, DW_INVALID_OFFSET);
1087   if (sect_offset == DW_INVALID_OFFSET)
1088     sect_offset = dwarf_cu_die.GetAttributeValueAsUnsigned(DW_AT_GNU_macros,
1089                                                            DW_INVALID_OFFSET);
1090   if (sect_offset == DW_INVALID_OFFSET)
1091     return false;
1092 
1093   comp_unit.SetDebugMacros(ParseDebugMacros(&sect_offset));
1094 
1095   return true;
1096 }
1097 
1098 size_t SymbolFileDWARF::ParseBlocksRecursive(
1099     lldb_private::CompileUnit &comp_unit, Block *parent_block,
1100     const DWARFDIE &orig_die, addr_t subprogram_low_pc, uint32_t depth) {
1101   size_t blocks_added = 0;
1102   DWARFDIE die = orig_die;
1103   while (die) {
1104     dw_tag_t tag = die.Tag();
1105 
1106     switch (tag) {
1107     case DW_TAG_inlined_subroutine:
1108     case DW_TAG_subprogram:
1109     case DW_TAG_lexical_block: {
1110       Block *block = nullptr;
1111       if (tag == DW_TAG_subprogram) {
1112         // Skip any DW_TAG_subprogram DIEs that are inside of a normal or
1113         // inlined functions. These will be parsed on their own as separate
1114         // entities.
1115 
1116         if (depth > 0)
1117           break;
1118 
1119         block = parent_block;
1120       } else {
1121         BlockSP block_sp(new Block(die.GetID()));
1122         parent_block->AddChild(block_sp);
1123         block = block_sp.get();
1124       }
1125       DWARFRangeList ranges;
1126       const char *name = nullptr;
1127       const char *mangled_name = nullptr;
1128 
1129       int decl_file = 0;
1130       int decl_line = 0;
1131       int decl_column = 0;
1132       int call_file = 0;
1133       int call_line = 0;
1134       int call_column = 0;
1135       if (die.GetDIENamesAndRanges(name, mangled_name, ranges, decl_file,
1136                                    decl_line, decl_column, call_file, call_line,
1137                                    call_column, nullptr)) {
1138         if (tag == DW_TAG_subprogram) {
1139           assert(subprogram_low_pc == LLDB_INVALID_ADDRESS);
1140           subprogram_low_pc = ranges.GetMinRangeBase(0);
1141         } else if (tag == DW_TAG_inlined_subroutine) {
1142           // We get called here for inlined subroutines in two ways. The first
1143           // time is when we are making the Function object for this inlined
1144           // concrete instance.  Since we're creating a top level block at
1145           // here, the subprogram_low_pc will be LLDB_INVALID_ADDRESS.  So we
1146           // need to adjust the containing address. The second time is when we
1147           // are parsing the blocks inside the function that contains the
1148           // inlined concrete instance.  Since these will be blocks inside the
1149           // containing "real" function the offset will be for that function.
1150           if (subprogram_low_pc == LLDB_INVALID_ADDRESS) {
1151             subprogram_low_pc = ranges.GetMinRangeBase(0);
1152           }
1153         }
1154 
1155         const size_t num_ranges = ranges.GetSize();
1156         for (size_t i = 0; i < num_ranges; ++i) {
1157           const DWARFRangeList::Entry &range = ranges.GetEntryRef(i);
1158           const addr_t range_base = range.GetRangeBase();
1159           if (range_base >= subprogram_low_pc)
1160             block->AddRange(Block::Range(range_base - subprogram_low_pc,
1161                                          range.GetByteSize()));
1162           else {
1163             GetObjectFile()->GetModule()->ReportError(
1164                 "0x%8.8" PRIx64 ": adding range [0x%" PRIx64 "-0x%" PRIx64
1165                 ") which has a base that is less than the function's low PC "
1166                 "0x%" PRIx64 ". Please file a bug and attach the file at the "
1167                 "start of this error message",
1168                 block->GetID(), range_base, range.GetRangeEnd(),
1169                 subprogram_low_pc);
1170           }
1171         }
1172         block->FinalizeRanges();
1173 
1174         if (tag != DW_TAG_subprogram &&
1175             (name != nullptr || mangled_name != nullptr)) {
1176           std::unique_ptr<Declaration> decl_up;
1177           if (decl_file != 0 || decl_line != 0 || decl_column != 0)
1178             decl_up.reset(new Declaration(
1179                 comp_unit.GetSupportFiles().GetFileSpecAtIndex(decl_file),
1180                 decl_line, decl_column));
1181 
1182           std::unique_ptr<Declaration> call_up;
1183           if (call_file != 0 || call_line != 0 || call_column != 0)
1184             call_up.reset(new Declaration(
1185                 comp_unit.GetSupportFiles().GetFileSpecAtIndex(call_file),
1186                 call_line, call_column));
1187 
1188           block->SetInlinedFunctionInfo(name, mangled_name, decl_up.get(),
1189                                         call_up.get());
1190         }
1191 
1192         ++blocks_added;
1193 
1194         if (die.HasChildren()) {
1195           blocks_added +=
1196               ParseBlocksRecursive(comp_unit, block, die.GetFirstChild(),
1197                                    subprogram_low_pc, depth + 1);
1198         }
1199       }
1200     } break;
1201     default:
1202       break;
1203     }
1204 
1205     // Only parse siblings of the block if we are not at depth zero. A depth of
1206     // zero indicates we are currently parsing the top level DW_TAG_subprogram
1207     // DIE
1208 
1209     if (depth == 0)
1210       die.Clear();
1211     else
1212       die = die.GetSibling();
1213   }
1214   return blocks_added;
1215 }
1216 
1217 bool SymbolFileDWARF::ClassOrStructIsVirtual(const DWARFDIE &parent_die) {
1218   if (parent_die) {
1219     for (DWARFDIE die = parent_die.GetFirstChild(); die;
1220          die = die.GetSibling()) {
1221       dw_tag_t tag = die.Tag();
1222       bool check_virtuality = false;
1223       switch (tag) {
1224       case DW_TAG_inheritance:
1225       case DW_TAG_subprogram:
1226         check_virtuality = true;
1227         break;
1228       default:
1229         break;
1230       }
1231       if (check_virtuality) {
1232         if (die.GetAttributeValueAsUnsigned(DW_AT_virtuality, 0) != 0)
1233           return true;
1234       }
1235     }
1236   }
1237   return false;
1238 }
1239 
1240 void SymbolFileDWARF::ParseDeclsForContext(CompilerDeclContext decl_ctx) {
1241   auto *type_system = decl_ctx.GetTypeSystem();
1242   if (type_system != nullptr)
1243     type_system->GetDWARFParser()->EnsureAllDIEsInDeclContextHaveBeenParsed(
1244         decl_ctx);
1245 }
1246 
1247 user_id_t SymbolFileDWARF::GetUID(DIERef ref) {
1248   if (GetDebugMapSymfile())
1249     return GetID() | ref.die_offset();
1250 
1251   return user_id_t(GetDwoNum().getValueOr(0x7fffffff)) << 32 |
1252          ref.die_offset() |
1253          (lldb::user_id_t(ref.section() == DIERef::Section::DebugTypes) << 63);
1254 }
1255 
1256 llvm::Optional<SymbolFileDWARF::DecodedUID>
1257 SymbolFileDWARF::DecodeUID(lldb::user_id_t uid) {
1258   // This method can be called without going through the symbol vendor so we
1259   // need to lock the module.
1260   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1261   // Anytime we get a "lldb::user_id_t" from an lldb_private::SymbolFile API we
1262   // must make sure we use the correct DWARF file when resolving things. On
1263   // MacOSX, when using SymbolFileDWARFDebugMap, we will use multiple
1264   // SymbolFileDWARF classes, one for each .o file. We can often end up with
1265   // references to other DWARF objects and we must be ready to receive a
1266   // "lldb::user_id_t" that specifies a DIE from another SymbolFileDWARF
1267   // instance.
1268   if (SymbolFileDWARFDebugMap *debug_map = GetDebugMapSymfile()) {
1269     SymbolFileDWARF *dwarf = debug_map->GetSymbolFileByOSOIndex(
1270         debug_map->GetOSOIndexFromUserID(uid));
1271     return DecodedUID{
1272         *dwarf, {llvm::None, DIERef::Section::DebugInfo, dw_offset_t(uid)}};
1273   }
1274   dw_offset_t die_offset = uid;
1275   if (die_offset == DW_INVALID_OFFSET)
1276     return llvm::None;
1277 
1278   DIERef::Section section =
1279       uid >> 63 ? DIERef::Section::DebugTypes : DIERef::Section::DebugInfo;
1280 
1281   llvm::Optional<uint32_t> dwo_num = uid >> 32 & 0x7fffffff;
1282   if (*dwo_num == 0x7fffffff)
1283     dwo_num = llvm::None;
1284 
1285   return DecodedUID{*this, {dwo_num, section, die_offset}};
1286 }
1287 
1288 DWARFDIE
1289 SymbolFileDWARF::GetDIE(lldb::user_id_t uid) {
1290   // This method can be called without going through the symbol vendor so we
1291   // need to lock the module.
1292   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1293 
1294   llvm::Optional<DecodedUID> decoded = DecodeUID(uid);
1295 
1296   if (decoded)
1297     return decoded->dwarf.GetDIE(decoded->ref);
1298 
1299   return DWARFDIE();
1300 }
1301 
1302 CompilerDecl SymbolFileDWARF::GetDeclForUID(lldb::user_id_t type_uid) {
1303   // This method can be called without going through the symbol vendor so we
1304   // need to lock the module.
1305   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1306   // Anytime we have a lldb::user_id_t, we must get the DIE by calling
1307   // SymbolFileDWARF::GetDIE(). See comments inside the
1308   // SymbolFileDWARF::GetDIE() for details.
1309   if (DWARFDIE die = GetDIE(type_uid))
1310     return die.GetDecl();
1311   return CompilerDecl();
1312 }
1313 
1314 CompilerDeclContext
1315 SymbolFileDWARF::GetDeclContextForUID(lldb::user_id_t type_uid) {
1316   // This method can be called without going through the symbol vendor so we
1317   // need to lock the module.
1318   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1319   // Anytime we have a lldb::user_id_t, we must get the DIE by calling
1320   // SymbolFileDWARF::GetDIE(). See comments inside the
1321   // SymbolFileDWARF::GetDIE() for details.
1322   if (DWARFDIE die = GetDIE(type_uid))
1323     return die.GetDeclContext();
1324   return CompilerDeclContext();
1325 }
1326 
1327 CompilerDeclContext
1328 SymbolFileDWARF::GetDeclContextContainingUID(lldb::user_id_t type_uid) {
1329   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1330   // Anytime we have a lldb::user_id_t, we must get the DIE by calling
1331   // SymbolFileDWARF::GetDIE(). See comments inside the
1332   // SymbolFileDWARF::GetDIE() for details.
1333   if (DWARFDIE die = GetDIE(type_uid))
1334     return die.GetContainingDeclContext();
1335   return CompilerDeclContext();
1336 }
1337 
1338 Type *SymbolFileDWARF::ResolveTypeUID(lldb::user_id_t type_uid) {
1339   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1340   // Anytime we have a lldb::user_id_t, we must get the DIE by calling
1341   // SymbolFileDWARF::GetDIE(). See comments inside the
1342   // SymbolFileDWARF::GetDIE() for details.
1343   if (DWARFDIE type_die = GetDIE(type_uid))
1344     return type_die.ResolveType();
1345   else
1346     return nullptr;
1347 }
1348 
1349 llvm::Optional<SymbolFile::ArrayInfo>
1350 SymbolFileDWARF::GetDynamicArrayInfoForUID(
1351     lldb::user_id_t type_uid, const lldb_private::ExecutionContext *exe_ctx) {
1352   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1353   if (DWARFDIE type_die = GetDIE(type_uid))
1354     return DWARFASTParser::ParseChildArrayInfo(type_die, exe_ctx);
1355   else
1356     return llvm::None;
1357 }
1358 
1359 Type *SymbolFileDWARF::ResolveTypeUID(const DIERef &die_ref) {
1360   return ResolveType(GetDIE(die_ref), true);
1361 }
1362 
1363 Type *SymbolFileDWARF::ResolveTypeUID(const DWARFDIE &die,
1364                                       bool assert_not_being_parsed) {
1365   if (die) {
1366     Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO));
1367     if (log)
1368       GetObjectFile()->GetModule()->LogMessage(
1369           log, "SymbolFileDWARF::ResolveTypeUID (die = 0x%8.8x) %s '%s'",
1370           die.GetOffset(), die.GetTagAsCString(), die.GetName());
1371 
1372     // We might be coming in in the middle of a type tree (a class within a
1373     // class, an enum within a class), so parse any needed parent DIEs before
1374     // we get to this one...
1375     DWARFDIE decl_ctx_die = GetDeclContextDIEContainingDIE(die);
1376     if (decl_ctx_die) {
1377       if (log) {
1378         switch (decl_ctx_die.Tag()) {
1379         case DW_TAG_structure_type:
1380         case DW_TAG_union_type:
1381         case DW_TAG_class_type: {
1382           // Get the type, which could be a forward declaration
1383           if (log)
1384             GetObjectFile()->GetModule()->LogMessage(
1385                 log,
1386                 "SymbolFileDWARF::ResolveTypeUID (die = 0x%8.8x) %s '%s' "
1387                 "resolve parent forward type for 0x%8.8x",
1388                 die.GetOffset(), die.GetTagAsCString(), die.GetName(),
1389                 decl_ctx_die.GetOffset());
1390         } break;
1391 
1392         default:
1393           break;
1394         }
1395       }
1396     }
1397     return ResolveType(die);
1398   }
1399   return nullptr;
1400 }
1401 
1402 // This function is used when SymbolFileDWARFDebugMap owns a bunch of
1403 // SymbolFileDWARF objects to detect if this DWARF file is the one that can
1404 // resolve a compiler_type.
1405 bool SymbolFileDWARF::HasForwardDeclForClangType(
1406     const CompilerType &compiler_type) {
1407   CompilerType compiler_type_no_qualifiers =
1408       ClangUtil::RemoveFastQualifiers(compiler_type);
1409   if (GetForwardDeclClangTypeToDie().count(
1410           compiler_type_no_qualifiers.GetOpaqueQualType())) {
1411     return true;
1412   }
1413   TypeSystem *type_system = compiler_type.GetTypeSystem();
1414 
1415   ClangASTContext *clang_type_system =
1416       llvm::dyn_cast_or_null<ClangASTContext>(type_system);
1417   if (!clang_type_system)
1418     return false;
1419   DWARFASTParserClang *ast_parser =
1420       static_cast<DWARFASTParserClang *>(clang_type_system->GetDWARFParser());
1421   return ast_parser->GetClangASTImporter().CanImport(compiler_type);
1422 }
1423 
1424 bool SymbolFileDWARF::CompleteType(CompilerType &compiler_type) {
1425   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1426 
1427   ClangASTContext *clang_type_system =
1428       llvm::dyn_cast_or_null<ClangASTContext>(compiler_type.GetTypeSystem());
1429   if (clang_type_system) {
1430     DWARFASTParserClang *ast_parser =
1431         static_cast<DWARFASTParserClang *>(clang_type_system->GetDWARFParser());
1432     if (ast_parser &&
1433         ast_parser->GetClangASTImporter().CanImport(compiler_type))
1434       return ast_parser->GetClangASTImporter().CompleteType(compiler_type);
1435   }
1436 
1437   // We have a struct/union/class/enum that needs to be fully resolved.
1438   CompilerType compiler_type_no_qualifiers =
1439       ClangUtil::RemoveFastQualifiers(compiler_type);
1440   auto die_it = GetForwardDeclClangTypeToDie().find(
1441       compiler_type_no_qualifiers.GetOpaqueQualType());
1442   if (die_it == GetForwardDeclClangTypeToDie().end()) {
1443     // We have already resolved this type...
1444     return true;
1445   }
1446 
1447   DWARFDIE dwarf_die = GetDIE(die_it->getSecond());
1448   if (dwarf_die) {
1449     // Once we start resolving this type, remove it from the forward
1450     // declaration map in case anyone child members or other types require this
1451     // type to get resolved. The type will get resolved when all of the calls
1452     // to SymbolFileDWARF::ResolveClangOpaqueTypeDefinition are done.
1453     GetForwardDeclClangTypeToDie().erase(die_it);
1454 
1455     Type *type = GetDIEToType().lookup(dwarf_die.GetDIE());
1456 
1457     Log *log(LogChannelDWARF::GetLogIfAny(DWARF_LOG_DEBUG_INFO |
1458                                           DWARF_LOG_TYPE_COMPLETION));
1459     if (log)
1460       GetObjectFile()->GetModule()->LogMessageVerboseBacktrace(
1461           log, "0x%8.8" PRIx64 ": %s '%s' resolving forward declaration...",
1462           dwarf_die.GetID(), dwarf_die.GetTagAsCString(),
1463           type->GetName().AsCString());
1464     assert(compiler_type);
1465     DWARFASTParser *dwarf_ast = dwarf_die.GetDWARFParser();
1466     if (dwarf_ast)
1467       return dwarf_ast->CompleteTypeFromDWARF(dwarf_die, type, compiler_type);
1468   }
1469   return false;
1470 }
1471 
1472 Type *SymbolFileDWARF::ResolveType(const DWARFDIE &die,
1473                                    bool assert_not_being_parsed,
1474                                    bool resolve_function_context) {
1475   if (die) {
1476     Type *type = GetTypeForDIE(die, resolve_function_context).get();
1477 
1478     if (assert_not_being_parsed) {
1479       if (type != DIE_IS_BEING_PARSED)
1480         return type;
1481 
1482       GetObjectFile()->GetModule()->ReportError(
1483           "Parsing a die that is being parsed die: 0x%8.8x: %s %s",
1484           die.GetOffset(), die.GetTagAsCString(), die.GetName());
1485 
1486     } else
1487       return type;
1488   }
1489   return nullptr;
1490 }
1491 
1492 CompileUnit *
1493 SymbolFileDWARF::GetCompUnitForDWARFCompUnit(DWARFCompileUnit &dwarf_cu) {
1494   // Check if the symbol vendor already knows about this compile unit?
1495   if (dwarf_cu.GetUserData() == nullptr) {
1496     // The symbol vendor doesn't know about this compile unit, we need to parse
1497     // and add it to the symbol vendor object.
1498     return ParseCompileUnit(dwarf_cu).get();
1499   }
1500   return (CompileUnit *)dwarf_cu.GetUserData();
1501 }
1502 
1503 size_t SymbolFileDWARF::GetObjCMethodDIEOffsets(ConstString class_name,
1504                                                 DIEArray &method_die_offsets) {
1505   method_die_offsets.clear();
1506   m_index->GetObjCMethods(class_name, method_die_offsets);
1507   return method_die_offsets.size();
1508 }
1509 
1510 bool SymbolFileDWARF::GetFunction(const DWARFDIE &die, SymbolContext &sc) {
1511   sc.Clear(false);
1512 
1513   if (die && llvm::isa<DWARFCompileUnit>(die.GetCU())) {
1514     // Check if the symbol vendor already knows about this compile unit?
1515     sc.comp_unit =
1516         GetCompUnitForDWARFCompUnit(llvm::cast<DWARFCompileUnit>(*die.GetCU()));
1517 
1518     sc.function = sc.comp_unit->FindFunctionByUID(die.GetID()).get();
1519     if (sc.function == nullptr)
1520       sc.function = ParseFunction(*sc.comp_unit, die);
1521 
1522     if (sc.function) {
1523       sc.module_sp = sc.function->CalculateSymbolContextModule();
1524       return true;
1525     }
1526   }
1527 
1528   return false;
1529 }
1530 
1531 lldb::ModuleSP SymbolFileDWARF::GetExternalModule(ConstString name) {
1532   UpdateExternalModuleListIfNeeded();
1533   const auto &pos = m_external_type_modules.find(name);
1534   if (pos != m_external_type_modules.end())
1535     return pos->second;
1536   else
1537     return lldb::ModuleSP();
1538 }
1539 
1540 DWARFDIE
1541 SymbolFileDWARF::GetDIE(const DIERef &die_ref) {
1542   if (die_ref.dwo_num()) {
1543     return DebugInfo()
1544         ->GetUnitAtIndex(*die_ref.dwo_num())
1545         ->GetDwoSymbolFile()
1546         ->GetDIE(die_ref);
1547   }
1548 
1549   DWARFDebugInfo *debug_info = DebugInfo();
1550   if (debug_info)
1551     return debug_info->GetDIE(die_ref);
1552   else
1553     return DWARFDIE();
1554 }
1555 
1556 std::unique_ptr<SymbolFileDWARFDwo>
1557 SymbolFileDWARF::GetDwoSymbolFileForCompileUnit(
1558     DWARFUnit &unit, const DWARFDebugInfoEntry &cu_die) {
1559   // If this is a Darwin-style debug map (non-.dSYM) symbol file,
1560   // never attempt to load ELF-style DWO files since the -gmodules
1561   // support uses the same DWO machanism to specify full debug info
1562   // files for modules. This is handled in
1563   // UpdateExternalModuleListIfNeeded().
1564   if (GetDebugMapSymfile())
1565     return nullptr;
1566 
1567   DWARFCompileUnit *dwarf_cu = llvm::dyn_cast<DWARFCompileUnit>(&unit);
1568   // Only compile units can be split into two parts.
1569   if (!dwarf_cu)
1570     return nullptr;
1571 
1572   const char *dwo_name =
1573       cu_die.GetAttributeValueAsString(dwarf_cu, DW_AT_GNU_dwo_name, nullptr);
1574   if (!dwo_name)
1575     return nullptr;
1576 
1577   SymbolFileDWARFDwp *dwp_symfile = GetDwpSymbolFile();
1578   if (dwp_symfile) {
1579     uint64_t dwo_id =
1580         cu_die.GetAttributeValueAsUnsigned(dwarf_cu, DW_AT_GNU_dwo_id, 0);
1581     std::unique_ptr<SymbolFileDWARFDwo> dwo_symfile =
1582         dwp_symfile->GetSymbolFileForDwoId(*dwarf_cu, dwo_id);
1583     if (dwo_symfile)
1584       return dwo_symfile;
1585   }
1586 
1587   FileSpec dwo_file(dwo_name);
1588   FileSystem::Instance().Resolve(dwo_file);
1589   if (dwo_file.IsRelative()) {
1590     const char *comp_dir =
1591         cu_die.GetAttributeValueAsString(dwarf_cu, DW_AT_comp_dir, nullptr);
1592     if (!comp_dir)
1593       return nullptr;
1594 
1595     dwo_file.SetFile(comp_dir, FileSpec::Style::native);
1596     FileSystem::Instance().Resolve(dwo_file);
1597     dwo_file.AppendPathComponent(dwo_name);
1598   }
1599 
1600   if (!FileSystem::Instance().Exists(dwo_file))
1601     return nullptr;
1602 
1603   const lldb::offset_t file_offset = 0;
1604   DataBufferSP dwo_file_data_sp;
1605   lldb::offset_t dwo_file_data_offset = 0;
1606   ObjectFileSP dwo_obj_file = ObjectFile::FindPlugin(
1607       GetObjectFile()->GetModule(), &dwo_file, file_offset,
1608       FileSystem::Instance().GetByteSize(dwo_file), dwo_file_data_sp,
1609       dwo_file_data_offset);
1610   if (dwo_obj_file == nullptr)
1611     return nullptr;
1612 
1613   return std::make_unique<SymbolFileDWARFDwo>(dwo_obj_file, *dwarf_cu);
1614 }
1615 
1616 void SymbolFileDWARF::UpdateExternalModuleListIfNeeded() {
1617   if (m_fetched_external_modules)
1618     return;
1619   m_fetched_external_modules = true;
1620 
1621   DWARFDebugInfo *debug_info = DebugInfo();
1622 
1623   // Follow DWO skeleton unit breadcrumbs.
1624   const uint32_t num_compile_units = GetNumCompileUnits();
1625   for (uint32_t cu_idx = 0; cu_idx < num_compile_units; ++cu_idx) {
1626     DWARFUnit *dwarf_cu = debug_info->GetUnitAtIndex(cu_idx);
1627     const DWARFBaseDIE die = dwarf_cu->GetUnitDIEOnly();
1628     if (!die || die.HasChildren())
1629       continue;
1630 
1631     const char *name = die.GetAttributeValueAsString(DW_AT_name, nullptr);
1632     if (!name)
1633       continue;
1634 
1635     ConstString const_name(name);
1636     ModuleSP &module_sp = m_external_type_modules[const_name];
1637     if (module_sp)
1638       continue;
1639 
1640     const char *dwo_path =
1641         die.GetAttributeValueAsString(DW_AT_GNU_dwo_name, nullptr);
1642     if (!dwo_path)
1643       dwo_path = die.GetAttributeValueAsString(DW_AT_dwo_name, nullptr);
1644     if (!dwo_path)
1645       continue;
1646 
1647     ModuleSpec dwo_module_spec;
1648     dwo_module_spec.GetFileSpec().SetFile(dwo_path, FileSpec::Style::native);
1649     if (dwo_module_spec.GetFileSpec().IsRelative()) {
1650       const char *comp_dir =
1651           die.GetAttributeValueAsString(DW_AT_comp_dir, nullptr);
1652       if (comp_dir) {
1653         dwo_module_spec.GetFileSpec().SetFile(comp_dir,
1654                                               FileSpec::Style::native);
1655         FileSystem::Instance().Resolve(dwo_module_spec.GetFileSpec());
1656         dwo_module_spec.GetFileSpec().AppendPathComponent(dwo_path);
1657       }
1658     }
1659     dwo_module_spec.GetArchitecture() =
1660         m_objfile_sp->GetModule()->GetArchitecture();
1661 
1662     // When LLDB loads "external" modules it looks at the presence of
1663     // DW_AT_dwo_name. However, when the already created module
1664     // (corresponding to .dwo itself) is being processed, it will see
1665     // the presence of DW_AT_dwo_name (which contains the name of dwo
1666     // file) and will try to call ModuleList::GetSharedModule
1667     // again. In some cases (i.e., for empty files) Clang 4.0
1668     // generates a *.dwo file which has DW_AT_dwo_name, but no
1669     // DW_AT_comp_dir. In this case the method
1670     // ModuleList::GetSharedModule will fail and the warning will be
1671     // printed. However, as one can notice in this case we don't
1672     // actually need to try to load the already loaded module
1673     // (corresponding to .dwo) so we simply skip it.
1674     if (m_objfile_sp->GetFileSpec().GetFileNameExtension() == ".dwo" &&
1675         llvm::StringRef(m_objfile_sp->GetFileSpec().GetPath())
1676             .endswith(dwo_module_spec.GetFileSpec().GetPath())) {
1677       continue;
1678     }
1679 
1680     Status error = ModuleList::GetSharedModule(dwo_module_spec, module_sp,
1681                                                nullptr, nullptr, nullptr);
1682     if (!module_sp) {
1683       GetObjectFile()->GetModule()->ReportWarning(
1684           "0x%8.8x: unable to locate module needed for external types: "
1685           "%s\nerror: %s\nDebugging will be degraded due to missing "
1686           "types. Rebuilding your project will regenerate the needed "
1687           "module files.",
1688           die.GetOffset(), dwo_module_spec.GetFileSpec().GetPath().c_str(),
1689           error.AsCString("unknown error"));
1690       continue;
1691     }
1692   }
1693 }
1694 
1695 SymbolFileDWARF::GlobalVariableMap &SymbolFileDWARF::GetGlobalAranges() {
1696   if (!m_global_aranges_up) {
1697     m_global_aranges_up.reset(new GlobalVariableMap());
1698 
1699     ModuleSP module_sp = GetObjectFile()->GetModule();
1700     if (module_sp) {
1701       const size_t num_cus = module_sp->GetNumCompileUnits();
1702       for (size_t i = 0; i < num_cus; ++i) {
1703         CompUnitSP cu_sp = module_sp->GetCompileUnitAtIndex(i);
1704         if (cu_sp) {
1705           VariableListSP globals_sp = cu_sp->GetVariableList(true);
1706           if (globals_sp) {
1707             const size_t num_globals = globals_sp->GetSize();
1708             for (size_t g = 0; g < num_globals; ++g) {
1709               VariableSP var_sp = globals_sp->GetVariableAtIndex(g);
1710               if (var_sp && !var_sp->GetLocationIsConstantValueData()) {
1711                 const DWARFExpression &location = var_sp->LocationExpression();
1712                 Value location_result;
1713                 Status error;
1714                 if (location.Evaluate(nullptr, LLDB_INVALID_ADDRESS, nullptr,
1715                                       nullptr, location_result, &error)) {
1716                   if (location_result.GetValueType() ==
1717                       Value::eValueTypeFileAddress) {
1718                     lldb::addr_t file_addr =
1719                         location_result.GetScalar().ULongLong();
1720                     lldb::addr_t byte_size = 1;
1721                     if (var_sp->GetType())
1722                       byte_size =
1723                           var_sp->GetType()->GetByteSize().getValueOr(0);
1724                     m_global_aranges_up->Append(GlobalVariableMap::Entry(
1725                         file_addr, byte_size, var_sp.get()));
1726                   }
1727                 }
1728               }
1729             }
1730           }
1731         }
1732       }
1733     }
1734     m_global_aranges_up->Sort();
1735   }
1736   return *m_global_aranges_up;
1737 }
1738 
1739 uint32_t SymbolFileDWARF::ResolveSymbolContext(const Address &so_addr,
1740                                                SymbolContextItem resolve_scope,
1741                                                SymbolContext &sc) {
1742   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1743   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
1744   Timer scoped_timer(func_cat,
1745                      "SymbolFileDWARF::"
1746                      "ResolveSymbolContext (so_addr = { "
1747                      "section = %p, offset = 0x%" PRIx64
1748                      " }, resolve_scope = 0x%8.8x)",
1749                      static_cast<void *>(so_addr.GetSection().get()),
1750                      so_addr.GetOffset(), resolve_scope);
1751   uint32_t resolved = 0;
1752   if (resolve_scope &
1753       (eSymbolContextCompUnit | eSymbolContextFunction | eSymbolContextBlock |
1754        eSymbolContextLineEntry | eSymbolContextVariable)) {
1755     lldb::addr_t file_vm_addr = so_addr.GetFileAddress();
1756 
1757     DWARFDebugInfo *debug_info = DebugInfo();
1758     if (debug_info) {
1759       llvm::Expected<DWARFDebugAranges &> aranges =
1760           debug_info->GetCompileUnitAranges();
1761       if (!aranges) {
1762         Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO);
1763         LLDB_LOG_ERROR(log, aranges.takeError(),
1764                        "SymbolFileDWARF::ResolveSymbolContext failed to get cu "
1765                        "aranges.  {0}");
1766         return 0;
1767       }
1768 
1769       const dw_offset_t cu_offset = aranges->FindAddress(file_vm_addr);
1770       if (cu_offset == DW_INVALID_OFFSET) {
1771         // Global variables are not in the compile unit address ranges. The
1772         // only way to currently find global variables is to iterate over the
1773         // .debug_pubnames or the __apple_names table and find all items in
1774         // there that point to DW_TAG_variable DIEs and then find the address
1775         // that matches.
1776         if (resolve_scope & eSymbolContextVariable) {
1777           GlobalVariableMap &map = GetGlobalAranges();
1778           const GlobalVariableMap::Entry *entry =
1779               map.FindEntryThatContains(file_vm_addr);
1780           if (entry && entry->data) {
1781             Variable *variable = entry->data;
1782             SymbolContextScope *scc = variable->GetSymbolContextScope();
1783             if (scc) {
1784               scc->CalculateSymbolContext(&sc);
1785               sc.variable = variable;
1786             }
1787             return sc.GetResolvedMask();
1788           }
1789         }
1790       } else {
1791         uint32_t cu_idx = DW_INVALID_INDEX;
1792         if (auto *dwarf_cu = llvm::dyn_cast_or_null<DWARFCompileUnit>(
1793                 debug_info->GetUnitAtOffset(DIERef::Section::DebugInfo,
1794                                             cu_offset, &cu_idx))) {
1795           sc.comp_unit = GetCompUnitForDWARFCompUnit(*dwarf_cu);
1796           if (sc.comp_unit) {
1797             resolved |= eSymbolContextCompUnit;
1798 
1799             bool force_check_line_table = false;
1800             if (resolve_scope &
1801                 (eSymbolContextFunction | eSymbolContextBlock)) {
1802               DWARFDIE function_die = dwarf_cu->LookupAddress(file_vm_addr);
1803               DWARFDIE block_die;
1804               if (function_die) {
1805                 sc.function =
1806                     sc.comp_unit->FindFunctionByUID(function_die.GetID()).get();
1807                 if (sc.function == nullptr)
1808                   sc.function = ParseFunction(*sc.comp_unit, function_die);
1809 
1810                 if (sc.function && (resolve_scope & eSymbolContextBlock))
1811                   block_die = function_die.LookupDeepestBlock(file_vm_addr);
1812               } else {
1813                 // We might have had a compile unit that had discontiguous
1814                 // address ranges where the gaps are symbols that don't have
1815                 // any debug info. Discontiguous compile unit address ranges
1816                 // should only happen when there aren't other functions from
1817                 // other compile units in these gaps. This helps keep the size
1818                 // of the aranges down.
1819                 force_check_line_table = true;
1820               }
1821 
1822               if (sc.function != nullptr) {
1823                 resolved |= eSymbolContextFunction;
1824 
1825                 if (resolve_scope & eSymbolContextBlock) {
1826                   Block &block = sc.function->GetBlock(true);
1827 
1828                   if (block_die)
1829                     sc.block = block.FindBlockByID(block_die.GetID());
1830                   else
1831                     sc.block = block.FindBlockByID(function_die.GetID());
1832                   if (sc.block)
1833                     resolved |= eSymbolContextBlock;
1834                 }
1835               }
1836             }
1837 
1838             if ((resolve_scope & eSymbolContextLineEntry) ||
1839                 force_check_line_table) {
1840               LineTable *line_table = sc.comp_unit->GetLineTable();
1841               if (line_table != nullptr) {
1842                 // And address that makes it into this function should be in
1843                 // terms of this debug file if there is no debug map, or it
1844                 // will be an address in the .o file which needs to be fixed up
1845                 // to be in terms of the debug map executable. Either way,
1846                 // calling FixupAddress() will work for us.
1847                 Address exe_so_addr(so_addr);
1848                 if (FixupAddress(exe_so_addr)) {
1849                   if (line_table->FindLineEntryByAddress(exe_so_addr,
1850                                                          sc.line_entry)) {
1851                     resolved |= eSymbolContextLineEntry;
1852                   }
1853                 }
1854               }
1855             }
1856 
1857             if (force_check_line_table &&
1858                 !(resolved & eSymbolContextLineEntry)) {
1859               // We might have had a compile unit that had discontiguous
1860               // address ranges where the gaps are symbols that don't have any
1861               // debug info. Discontiguous compile unit address ranges should
1862               // only happen when there aren't other functions from other
1863               // compile units in these gaps. This helps keep the size of the
1864               // aranges down.
1865               sc.comp_unit = nullptr;
1866               resolved &= ~eSymbolContextCompUnit;
1867             }
1868           } else {
1869             GetObjectFile()->GetModule()->ReportWarning(
1870                 "0x%8.8x: compile unit %u failed to create a valid "
1871                 "lldb_private::CompileUnit class.",
1872                 cu_offset, cu_idx);
1873           }
1874         }
1875       }
1876     }
1877   }
1878   return resolved;
1879 }
1880 
1881 uint32_t SymbolFileDWARF::ResolveSymbolContext(const FileSpec &file_spec,
1882                                                uint32_t line,
1883                                                bool check_inlines,
1884                                                SymbolContextItem resolve_scope,
1885                                                SymbolContextList &sc_list) {
1886   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1887   const uint32_t prev_size = sc_list.GetSize();
1888   if (resolve_scope & eSymbolContextCompUnit) {
1889     for (uint32_t cu_idx = 0, num_cus = GetNumCompileUnits(); cu_idx < num_cus;
1890          ++cu_idx) {
1891       CompileUnit *dc_cu = ParseCompileUnitAtIndex(cu_idx).get();
1892       if (!dc_cu)
1893         continue;
1894 
1895       const bool full_match = (bool)file_spec.GetDirectory();
1896       bool file_spec_matches_cu_file_spec =
1897           FileSpec::Equal(file_spec, *dc_cu, full_match);
1898       if (check_inlines || file_spec_matches_cu_file_spec) {
1899         SymbolContext sc(m_objfile_sp->GetModule());
1900         sc.comp_unit = dc_cu;
1901         uint32_t file_idx = UINT32_MAX;
1902 
1903         // If we are looking for inline functions only and we don't find it
1904         // in the support files, we are done.
1905         if (check_inlines) {
1906           file_idx =
1907               sc.comp_unit->GetSupportFiles().FindFileIndex(1, file_spec, true);
1908           if (file_idx == UINT32_MAX)
1909             continue;
1910         }
1911 
1912         if (line != 0) {
1913           LineTable *line_table = sc.comp_unit->GetLineTable();
1914 
1915           if (line_table != nullptr && line != 0) {
1916             // We will have already looked up the file index if we are
1917             // searching for inline entries.
1918             if (!check_inlines)
1919               file_idx = sc.comp_unit->GetSupportFiles().FindFileIndex(
1920                   1, file_spec, true);
1921 
1922             if (file_idx != UINT32_MAX) {
1923               uint32_t found_line;
1924               uint32_t line_idx = line_table->FindLineEntryIndexByFileIndex(
1925                   0, file_idx, line, false, &sc.line_entry);
1926               found_line = sc.line_entry.line;
1927 
1928               while (line_idx != UINT32_MAX) {
1929                 sc.function = nullptr;
1930                 sc.block = nullptr;
1931                 if (resolve_scope &
1932                     (eSymbolContextFunction | eSymbolContextBlock)) {
1933                   const lldb::addr_t file_vm_addr =
1934                       sc.line_entry.range.GetBaseAddress().GetFileAddress();
1935                   if (file_vm_addr != LLDB_INVALID_ADDRESS) {
1936                     DWARFDIE function_die =
1937                         GetDWARFCompileUnit(dc_cu)->LookupAddress(file_vm_addr);
1938                     DWARFDIE block_die;
1939                     if (function_die) {
1940                       sc.function =
1941                           sc.comp_unit->FindFunctionByUID(function_die.GetID())
1942                               .get();
1943                       if (sc.function == nullptr)
1944                         sc.function =
1945                             ParseFunction(*sc.comp_unit, function_die);
1946 
1947                       if (sc.function && (resolve_scope & eSymbolContextBlock))
1948                         block_die =
1949                             function_die.LookupDeepestBlock(file_vm_addr);
1950                     }
1951 
1952                     if (sc.function != nullptr) {
1953                       Block &block = sc.function->GetBlock(true);
1954 
1955                       if (block_die)
1956                         sc.block = block.FindBlockByID(block_die.GetID());
1957                       else if (function_die)
1958                         sc.block = block.FindBlockByID(function_die.GetID());
1959                     }
1960                   }
1961                 }
1962 
1963                 sc_list.Append(sc);
1964                 line_idx = line_table->FindLineEntryIndexByFileIndex(
1965                     line_idx + 1, file_idx, found_line, true, &sc.line_entry);
1966               }
1967             }
1968           } else if (file_spec_matches_cu_file_spec && !check_inlines) {
1969             // only append the context if we aren't looking for inline call
1970             // sites by file and line and if the file spec matches that of
1971             // the compile unit
1972             sc_list.Append(sc);
1973           }
1974         } else if (file_spec_matches_cu_file_spec && !check_inlines) {
1975           // only append the context if we aren't looking for inline call
1976           // sites by file and line and if the file spec matches that of
1977           // the compile unit
1978           sc_list.Append(sc);
1979         }
1980 
1981         if (!check_inlines)
1982           break;
1983       }
1984     }
1985   }
1986   return sc_list.GetSize() - prev_size;
1987 }
1988 
1989 void SymbolFileDWARF::PreloadSymbols() {
1990   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1991   m_index->Preload();
1992 }
1993 
1994 std::recursive_mutex &SymbolFileDWARF::GetModuleMutex() const {
1995   lldb::ModuleSP module_sp(m_debug_map_module_wp.lock());
1996   if (module_sp)
1997     return module_sp->GetMutex();
1998   return GetObjectFile()->GetModule()->GetMutex();
1999 }
2000 
2001 bool SymbolFileDWARF::DeclContextMatchesThisSymbolFile(
2002     const lldb_private::CompilerDeclContext *decl_ctx) {
2003   if (decl_ctx == nullptr || !decl_ctx->IsValid()) {
2004     // Invalid namespace decl which means we aren't matching only things in
2005     // this symbol file, so return true to indicate it matches this symbol
2006     // file.
2007     return true;
2008   }
2009 
2010   TypeSystem *decl_ctx_type_system = decl_ctx->GetTypeSystem();
2011   auto type_system_or_err = GetTypeSystemForLanguage(
2012       decl_ctx_type_system->GetMinimumLanguage(nullptr));
2013   if (auto err = type_system_or_err.takeError()) {
2014     LLDB_LOG_ERROR(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_SYMBOLS),
2015                    std::move(err),
2016                    "Unable to match namespace decl using TypeSystem");
2017     return false;
2018   }
2019 
2020   if (decl_ctx_type_system == &type_system_or_err.get())
2021     return true; // The type systems match, return true
2022 
2023   // The namespace AST was valid, and it does not match...
2024   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2025 
2026   if (log)
2027     GetObjectFile()->GetModule()->LogMessage(
2028         log, "Valid namespace does not match symbol file");
2029 
2030   return false;
2031 }
2032 
2033 void SymbolFileDWARF::FindGlobalVariables(
2034     ConstString name, const CompilerDeclContext *parent_decl_ctx,
2035     uint32_t max_matches, VariableList &variables) {
2036   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
2037   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2038 
2039   if (log)
2040     GetObjectFile()->GetModule()->LogMessage(
2041         log,
2042         "SymbolFileDWARF::FindGlobalVariables (name=\"%s\", "
2043         "parent_decl_ctx=%p, max_matches=%u, variables)",
2044         name.GetCString(), static_cast<const void *>(parent_decl_ctx),
2045         max_matches);
2046 
2047   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
2048     return;
2049 
2050   DWARFDebugInfo *info = DebugInfo();
2051   if (!info)
2052     return;
2053 
2054   // Remember how many variables are in the list before we search.
2055   const uint32_t original_size = variables.GetSize();
2056 
2057   llvm::StringRef basename;
2058   llvm::StringRef context;
2059   bool name_is_mangled = (bool)Mangled(name);
2060 
2061   if (!CPlusPlusLanguage::ExtractContextAndIdentifier(name.GetCString(),
2062                                                       context, basename))
2063     basename = name.GetStringRef();
2064 
2065   DIEArray die_offsets;
2066   m_index->GetGlobalVariables(ConstString(basename), die_offsets);
2067   const size_t num_die_matches = die_offsets.size();
2068   if (num_die_matches) {
2069     SymbolContext sc;
2070     sc.module_sp = m_objfile_sp->GetModule();
2071     assert(sc.module_sp);
2072 
2073     // Loop invariant: Variables up to this index have been checked for context
2074     // matches.
2075     uint32_t pruned_idx = original_size;
2076 
2077     bool done = false;
2078     for (size_t i = 0; i < num_die_matches && !done; ++i) {
2079       const DIERef &die_ref = die_offsets[i];
2080       DWARFDIE die = GetDIE(die_ref);
2081 
2082       if (die) {
2083         switch (die.Tag()) {
2084         default:
2085         case DW_TAG_subprogram:
2086         case DW_TAG_inlined_subroutine:
2087         case DW_TAG_try_block:
2088         case DW_TAG_catch_block:
2089           break;
2090 
2091         case DW_TAG_variable: {
2092           auto *dwarf_cu = llvm::dyn_cast<DWARFCompileUnit>(die.GetCU());
2093           if (!dwarf_cu)
2094             continue;
2095           sc.comp_unit = GetCompUnitForDWARFCompUnit(*dwarf_cu);
2096 
2097           if (parent_decl_ctx) {
2098             DWARFASTParser *dwarf_ast = die.GetDWARFParser();
2099             if (dwarf_ast) {
2100               CompilerDeclContext actual_parent_decl_ctx =
2101                   dwarf_ast->GetDeclContextContainingUIDFromDWARF(die);
2102               if (!actual_parent_decl_ctx ||
2103                   actual_parent_decl_ctx != *parent_decl_ctx)
2104                 continue;
2105             }
2106           }
2107 
2108           ParseVariables(sc, die, LLDB_INVALID_ADDRESS, false, false,
2109                          &variables);
2110           while (pruned_idx < variables.GetSize()) {
2111             VariableSP var_sp = variables.GetVariableAtIndex(pruned_idx);
2112             if (name_is_mangled ||
2113                 var_sp->GetName().GetStringRef().contains(name.GetStringRef()))
2114               ++pruned_idx;
2115             else
2116               variables.RemoveVariableAtIndex(pruned_idx);
2117           }
2118 
2119           if (variables.GetSize() - original_size >= max_matches)
2120             done = true;
2121         } break;
2122         }
2123       } else {
2124         m_index->ReportInvalidDIERef(die_ref, name.GetStringRef());
2125       }
2126     }
2127   }
2128 
2129   // Return the number of variable that were appended to the list
2130   const uint32_t num_matches = variables.GetSize() - original_size;
2131   if (log && num_matches > 0) {
2132     GetObjectFile()->GetModule()->LogMessage(
2133         log,
2134         "SymbolFileDWARF::FindGlobalVariables (name=\"%s\", "
2135         "parent_decl_ctx=%p, max_matches=%u, variables) => %u",
2136         name.GetCString(), static_cast<const void *>(parent_decl_ctx),
2137         max_matches, num_matches);
2138   }
2139 }
2140 
2141 void SymbolFileDWARF::FindGlobalVariables(const RegularExpression &regex,
2142                                           uint32_t max_matches,
2143                                           VariableList &variables) {
2144   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
2145   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2146 
2147   if (log) {
2148     GetObjectFile()->GetModule()->LogMessage(
2149         log,
2150         "SymbolFileDWARF::FindGlobalVariables (regex=\"%s\", "
2151         "max_matches=%u, variables)",
2152         regex.GetText().str().c_str(), max_matches);
2153   }
2154 
2155   DWARFDebugInfo *info = DebugInfo();
2156   if (!info)
2157     return;
2158 
2159   // Remember how many variables are in the list before we search.
2160   const uint32_t original_size = variables.GetSize();
2161 
2162   DIEArray die_offsets;
2163   m_index->GetGlobalVariables(regex, die_offsets);
2164 
2165   SymbolContext sc;
2166   sc.module_sp = m_objfile_sp->GetModule();
2167   assert(sc.module_sp);
2168 
2169   const size_t num_matches = die_offsets.size();
2170   if (num_matches) {
2171     for (size_t i = 0; i < num_matches; ++i) {
2172       const DIERef &die_ref = die_offsets[i];
2173       DWARFDIE die = GetDIE(die_ref);
2174 
2175       if (die) {
2176         DWARFCompileUnit *dwarf_cu =
2177             llvm::dyn_cast<DWARFCompileUnit>(die.GetCU());
2178         if (!dwarf_cu)
2179           continue;
2180         sc.comp_unit = GetCompUnitForDWARFCompUnit(*dwarf_cu);
2181 
2182         ParseVariables(sc, die, LLDB_INVALID_ADDRESS, false, false, &variables);
2183 
2184         if (variables.GetSize() - original_size >= max_matches)
2185           break;
2186       } else
2187         m_index->ReportInvalidDIERef(die_ref, regex.GetText());
2188     }
2189   }
2190 }
2191 
2192 bool SymbolFileDWARF::ResolveFunction(const DWARFDIE &orig_die,
2193                                       bool include_inlines,
2194                                       SymbolContextList &sc_list) {
2195   SymbolContext sc;
2196 
2197   if (!orig_die)
2198     return false;
2199 
2200   // If we were passed a die that is not a function, just return false...
2201   if (!(orig_die.Tag() == DW_TAG_subprogram ||
2202         (include_inlines && orig_die.Tag() == DW_TAG_inlined_subroutine)))
2203     return false;
2204 
2205   DWARFDIE die = orig_die;
2206   DWARFDIE inlined_die;
2207   if (die.Tag() == DW_TAG_inlined_subroutine) {
2208     inlined_die = die;
2209 
2210     while (true) {
2211       die = die.GetParent();
2212 
2213       if (die) {
2214         if (die.Tag() == DW_TAG_subprogram)
2215           break;
2216       } else
2217         break;
2218     }
2219   }
2220   assert(die && die.Tag() == DW_TAG_subprogram);
2221   if (GetFunction(die, sc)) {
2222     Address addr;
2223     // Parse all blocks if needed
2224     if (inlined_die) {
2225       Block &function_block = sc.function->GetBlock(true);
2226       sc.block = function_block.FindBlockByID(inlined_die.GetID());
2227       if (sc.block == nullptr)
2228         sc.block = function_block.FindBlockByID(inlined_die.GetOffset());
2229       if (sc.block == nullptr || !sc.block->GetStartAddress(addr))
2230         addr.Clear();
2231     } else {
2232       sc.block = nullptr;
2233       addr = sc.function->GetAddressRange().GetBaseAddress();
2234     }
2235 
2236     if (addr.IsValid()) {
2237       sc_list.Append(sc);
2238       return true;
2239     }
2240   }
2241 
2242   return false;
2243 }
2244 
2245 bool SymbolFileDWARF::DIEInDeclContext(const CompilerDeclContext *decl_ctx,
2246                                        const DWARFDIE &die) {
2247   // If we have no parent decl context to match this DIE matches, and if the
2248   // parent decl context isn't valid, we aren't trying to look for any
2249   // particular decl context so any die matches.
2250   if (decl_ctx == nullptr || !decl_ctx->IsValid())
2251     return true;
2252 
2253   if (die) {
2254     DWARFASTParser *dwarf_ast = die.GetDWARFParser();
2255     if (dwarf_ast) {
2256       CompilerDeclContext actual_decl_ctx =
2257           dwarf_ast->GetDeclContextContainingUIDFromDWARF(die);
2258       if (actual_decl_ctx)
2259         return decl_ctx->IsContainedInLookup(actual_decl_ctx);
2260     }
2261   }
2262   return false;
2263 }
2264 
2265 void SymbolFileDWARF::FindFunctions(ConstString name,
2266                                     const CompilerDeclContext *parent_decl_ctx,
2267                                     FunctionNameType name_type_mask,
2268                                     bool include_inlines,
2269                                     SymbolContextList &sc_list) {
2270   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
2271   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
2272   Timer scoped_timer(func_cat, "SymbolFileDWARF::FindFunctions (name = '%s')",
2273                      name.AsCString());
2274 
2275   // eFunctionNameTypeAuto should be pre-resolved by a call to
2276   // Module::LookupInfo::LookupInfo()
2277   assert((name_type_mask & eFunctionNameTypeAuto) == 0);
2278 
2279   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2280 
2281   if (log) {
2282     GetObjectFile()->GetModule()->LogMessage(
2283         log,
2284         "SymbolFileDWARF::FindFunctions (name=\"%s\", name_type_mask=0x%x, sc_list)",
2285         name.GetCString(), name_type_mask);
2286   }
2287 
2288   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
2289     return;
2290 
2291   // If name is empty then we won't find anything.
2292   if (name.IsEmpty())
2293     return;
2294 
2295   // Remember how many sc_list are in the list before we search in case we are
2296   // appending the results to a variable list.
2297 
2298   const uint32_t original_size = sc_list.GetSize();
2299 
2300   llvm::DenseSet<const DWARFDebugInfoEntry *> resolved_dies;
2301   DIEArray offsets;
2302   CompilerDeclContext empty_decl_ctx;
2303   if (!parent_decl_ctx)
2304     parent_decl_ctx = &empty_decl_ctx;
2305 
2306   std::vector<DWARFDIE> dies;
2307   m_index->GetFunctions(name, *this, *parent_decl_ctx, name_type_mask, dies);
2308   for (const DWARFDIE &die : dies) {
2309     if (resolved_dies.insert(die.GetDIE()).second)
2310       ResolveFunction(die, include_inlines, sc_list);
2311   }
2312 
2313   // Return the number of variable that were appended to the list
2314   const uint32_t num_matches = sc_list.GetSize() - original_size;
2315 
2316   if (log && num_matches > 0) {
2317     GetObjectFile()->GetModule()->LogMessage(
2318         log,
2319         "SymbolFileDWARF::FindFunctions (name=\"%s\", "
2320         "name_type_mask=0x%x, include_inlines=%d, sc_list) => %u",
2321         name.GetCString(), name_type_mask, include_inlines,
2322         num_matches);
2323   }
2324 }
2325 
2326 void SymbolFileDWARF::FindFunctions(const RegularExpression &regex,
2327                                     bool include_inlines,
2328                                     SymbolContextList &sc_list) {
2329   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
2330   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
2331   Timer scoped_timer(func_cat, "SymbolFileDWARF::FindFunctions (regex = '%s')",
2332                      regex.GetText().str().c_str());
2333 
2334   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2335 
2336   if (log) {
2337     GetObjectFile()->GetModule()->LogMessage(
2338         log, "SymbolFileDWARF::FindFunctions (regex=\"%s\", sc_list)",
2339         regex.GetText().str().c_str());
2340   }
2341 
2342   DWARFDebugInfo *info = DebugInfo();
2343   if (!info)
2344     return;
2345 
2346   DIEArray offsets;
2347   m_index->GetFunctions(regex, offsets);
2348 
2349   llvm::DenseSet<const DWARFDebugInfoEntry *> resolved_dies;
2350   for (DIERef ref : offsets) {
2351     DWARFDIE die = info->GetDIE(ref);
2352     if (!die) {
2353       m_index->ReportInvalidDIERef(ref, regex.GetText());
2354       continue;
2355     }
2356     if (resolved_dies.insert(die.GetDIE()).second)
2357       ResolveFunction(die, include_inlines, sc_list);
2358   }
2359 }
2360 
2361 void SymbolFileDWARF::GetMangledNamesForFunction(
2362     const std::string &scope_qualified_name,
2363     std::vector<ConstString> &mangled_names) {
2364   DWARFDebugInfo *info = DebugInfo();
2365   uint32_t num_comp_units = 0;
2366   if (info)
2367     num_comp_units = info->GetNumUnits();
2368 
2369   for (uint32_t i = 0; i < num_comp_units; i++) {
2370     DWARFUnit *cu = info->GetUnitAtIndex(i);
2371     if (cu == nullptr)
2372       continue;
2373 
2374     SymbolFileDWARFDwo *dwo = cu->GetDwoSymbolFile();
2375     if (dwo)
2376       dwo->GetMangledNamesForFunction(scope_qualified_name, mangled_names);
2377   }
2378 
2379   for (lldb::user_id_t uid :
2380        m_function_scope_qualified_name_map.lookup(scope_qualified_name)) {
2381     DWARFDIE die = GetDIE(uid);
2382     mangled_names.push_back(ConstString(die.GetMangledName()));
2383   }
2384 }
2385 
2386 void SymbolFileDWARF::FindTypes(
2387     ConstString name, const CompilerDeclContext *parent_decl_ctx,
2388     uint32_t max_matches,
2389     llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
2390     TypeMap &types) {
2391   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
2392   // Make sure we haven't already searched this SymbolFile before.
2393   if (!searched_symbol_files.insert(this).second)
2394     return;
2395 
2396   DWARFDebugInfo *info = DebugInfo();
2397   if (!info)
2398     return;
2399 
2400   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2401 
2402   if (log) {
2403     if (parent_decl_ctx)
2404       GetObjectFile()->GetModule()->LogMessage(
2405           log,
2406           "SymbolFileDWARF::FindTypes (sc, name=\"%s\", parent_decl_ctx = "
2407           "%p (\"%s\"), max_matches=%u, type_list)",
2408           name.GetCString(), static_cast<const void *>(parent_decl_ctx),
2409           parent_decl_ctx->GetName().AsCString("<NULL>"), max_matches);
2410     else
2411       GetObjectFile()->GetModule()->LogMessage(
2412           log,
2413           "SymbolFileDWARF::FindTypes (sc, name=\"%s\", parent_decl_ctx = "
2414           "NULL, max_matches=%u, type_list)",
2415           name.GetCString(), max_matches);
2416   }
2417 
2418   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
2419     return;
2420 
2421   DIEArray die_offsets;
2422   m_index->GetTypes(name, die_offsets);
2423   const size_t num_die_matches = die_offsets.size();
2424 
2425   for (size_t i = 0; i < num_die_matches; ++i) {
2426     const DIERef &die_ref = die_offsets[i];
2427     DWARFDIE die = GetDIE(die_ref);
2428     if (die) {
2429       if (!DIEInDeclContext(parent_decl_ctx, die))
2430         continue; // The containing decl contexts don't match
2431 
2432       Type *matching_type = ResolveType(die, true, true);
2433       if (matching_type) {
2434         // We found a type pointer, now find the shared pointer form our type
2435         // list
2436         types.InsertUnique(matching_type->shared_from_this());
2437         if (types.GetSize() >= max_matches)
2438           break;
2439       }
2440     } else {
2441       m_index->ReportInvalidDIERef(die_ref, name.GetStringRef());
2442     }
2443   }
2444 
2445   // Next search through the reachable Clang modules. This only applies for
2446   // DWARF objects compiled with -gmodules that haven't been processed by
2447   // dsymutil.
2448   if (num_die_matches < max_matches) {
2449     UpdateExternalModuleListIfNeeded();
2450 
2451     for (const auto &pair : m_external_type_modules)
2452       if (ModuleSP external_module_sp = pair.second)
2453         if (SymbolFile *sym_file = external_module_sp->GetSymbolFile())
2454           sym_file->FindTypes(name, parent_decl_ctx, max_matches,
2455                               searched_symbol_files, types);
2456   }
2457 
2458   if (log && types.GetSize()) {
2459     if (parent_decl_ctx) {
2460       GetObjectFile()->GetModule()->LogMessage(
2461           log,
2462           "SymbolFileDWARF::FindTypes (sc, name=\"%s\", parent_decl_ctx "
2463           "= %p (\"%s\"), max_matches=%u, type_list) => %u",
2464           name.GetCString(), static_cast<const void *>(parent_decl_ctx),
2465           parent_decl_ctx->GetName().AsCString("<NULL>"), max_matches,
2466           types.GetSize());
2467     } else {
2468       GetObjectFile()->GetModule()->LogMessage(
2469           log,
2470           "SymbolFileDWARF::FindTypes (sc, name=\"%s\", parent_decl_ctx "
2471           "= NULL, max_matches=%u, type_list) => %u",
2472           name.GetCString(), max_matches, types.GetSize());
2473     }
2474   }
2475 }
2476 
2477 void SymbolFileDWARF::FindTypes(
2478     llvm::ArrayRef<CompilerContext> pattern, LanguageSet languages,
2479     llvm::DenseSet<SymbolFile *> &searched_symbol_files, TypeMap &types) {
2480   // Make sure we haven't already searched this SymbolFile before.
2481   if (!searched_symbol_files.insert(this).second)
2482     return;
2483 
2484   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
2485   if (pattern.empty())
2486     return;
2487 
2488   ConstString name = pattern.back().name;
2489 
2490   if (!name)
2491     return;
2492 
2493   DIEArray die_offsets;
2494   m_index->GetTypes(name, die_offsets);
2495   const size_t num_die_matches = die_offsets.size();
2496 
2497   for (size_t i = 0; i < num_die_matches; ++i) {
2498     const DIERef &die_ref = die_offsets[i];
2499     DWARFDIE die = GetDIE(die_ref);
2500 
2501     if (!die) {
2502       m_index->ReportInvalidDIERef(die_ref, name.GetStringRef());
2503       continue;
2504     }
2505     if (!languages[die.GetCU()->GetLanguageType()])
2506       continue;
2507 
2508     llvm::SmallVector<CompilerContext, 4> die_context;
2509     die.GetDeclContext(die_context);
2510     if (!contextMatches(die_context, pattern))
2511       continue;
2512 
2513     if (Type *matching_type = ResolveType(die, true, true)) {
2514       // We found a type pointer, now find the shared pointer form our type
2515       // list.
2516       types.InsertUnique(matching_type->shared_from_this());
2517     }
2518   }
2519 
2520   // Next search through the reachable Clang modules. This only applies for
2521   // DWARF objects compiled with -gmodules that haven't been processed by
2522   // dsymutil.
2523   UpdateExternalModuleListIfNeeded();
2524 
2525   for (const auto &pair : m_external_type_modules)
2526     if (ModuleSP external_module_sp = pair.second)
2527       external_module_sp->FindTypes(pattern, languages, searched_symbol_files,
2528                                     types);
2529 }
2530 
2531 CompilerDeclContext
2532 SymbolFileDWARF::FindNamespace(ConstString name,
2533                                const CompilerDeclContext *parent_decl_ctx) {
2534   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
2535   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2536 
2537   if (log) {
2538     GetObjectFile()->GetModule()->LogMessage(
2539         log, "SymbolFileDWARF::FindNamespace (sc, name=\"%s\")",
2540         name.GetCString());
2541   }
2542 
2543   CompilerDeclContext namespace_decl_ctx;
2544 
2545   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
2546     return namespace_decl_ctx;
2547 
2548   DWARFDebugInfo *info = DebugInfo();
2549   if (info) {
2550     DIEArray die_offsets;
2551     m_index->GetNamespaces(name, die_offsets);
2552     const size_t num_matches = die_offsets.size();
2553     if (num_matches) {
2554       for (size_t i = 0; i < num_matches; ++i) {
2555         const DIERef &die_ref = die_offsets[i];
2556         DWARFDIE die = GetDIE(die_ref);
2557 
2558         if (die) {
2559           if (!DIEInDeclContext(parent_decl_ctx, die))
2560             continue; // The containing decl contexts don't match
2561 
2562           DWARFASTParser *dwarf_ast = die.GetDWARFParser();
2563           if (dwarf_ast) {
2564             namespace_decl_ctx = dwarf_ast->GetDeclContextForUIDFromDWARF(die);
2565             if (namespace_decl_ctx)
2566               break;
2567           }
2568         } else {
2569           m_index->ReportInvalidDIERef(die_ref, name.GetStringRef());
2570         }
2571       }
2572     }
2573   }
2574   if (log && namespace_decl_ctx) {
2575     GetObjectFile()->GetModule()->LogMessage(
2576         log,
2577         "SymbolFileDWARF::FindNamespace (sc, name=\"%s\") => "
2578         "CompilerDeclContext(%p/%p) \"%s\"",
2579         name.GetCString(),
2580         static_cast<const void *>(namespace_decl_ctx.GetTypeSystem()),
2581         static_cast<const void *>(namespace_decl_ctx.GetOpaqueDeclContext()),
2582         namespace_decl_ctx.GetName().AsCString("<NULL>"));
2583   }
2584 
2585   return namespace_decl_ctx;
2586 }
2587 
2588 TypeSP SymbolFileDWARF::GetTypeForDIE(const DWARFDIE &die,
2589                                       bool resolve_function_context) {
2590   TypeSP type_sp;
2591   if (die) {
2592     Type *type_ptr = GetDIEToType().lookup(die.GetDIE());
2593     if (type_ptr == nullptr) {
2594       SymbolContextScope *scope;
2595       if (auto *dwarf_cu = llvm::dyn_cast<DWARFCompileUnit>(die.GetCU()))
2596         scope = GetCompUnitForDWARFCompUnit(*dwarf_cu);
2597       else
2598         scope = GetObjectFile()->GetModule().get();
2599       assert(scope);
2600       SymbolContext sc(scope);
2601       const DWARFDebugInfoEntry *parent_die = die.GetParent().GetDIE();
2602       while (parent_die != nullptr) {
2603         if (parent_die->Tag() == DW_TAG_subprogram)
2604           break;
2605         parent_die = parent_die->GetParent();
2606       }
2607       SymbolContext sc_backup = sc;
2608       if (resolve_function_context && parent_die != nullptr &&
2609           !GetFunction(DWARFDIE(die.GetCU(), parent_die), sc))
2610         sc = sc_backup;
2611 
2612       type_sp = ParseType(sc, die, nullptr);
2613     } else if (type_ptr != DIE_IS_BEING_PARSED) {
2614       // Grab the existing type from the master types lists
2615       type_sp = type_ptr->shared_from_this();
2616     }
2617   }
2618   return type_sp;
2619 }
2620 
2621 DWARFDIE
2622 SymbolFileDWARF::GetDeclContextDIEContainingDIE(const DWARFDIE &orig_die) {
2623   if (orig_die) {
2624     DWARFDIE die = orig_die;
2625 
2626     while (die) {
2627       // If this is the original DIE that we are searching for a declaration
2628       // for, then don't look in the cache as we don't want our own decl
2629       // context to be our decl context...
2630       if (orig_die != die) {
2631         switch (die.Tag()) {
2632         case DW_TAG_compile_unit:
2633         case DW_TAG_partial_unit:
2634         case DW_TAG_namespace:
2635         case DW_TAG_structure_type:
2636         case DW_TAG_union_type:
2637         case DW_TAG_class_type:
2638         case DW_TAG_lexical_block:
2639         case DW_TAG_subprogram:
2640           return die;
2641         case DW_TAG_inlined_subroutine: {
2642           DWARFDIE abs_die = die.GetReferencedDIE(DW_AT_abstract_origin);
2643           if (abs_die) {
2644             return abs_die;
2645           }
2646           break;
2647         }
2648         default:
2649           break;
2650         }
2651       }
2652 
2653       DWARFDIE spec_die = die.GetReferencedDIE(DW_AT_specification);
2654       if (spec_die) {
2655         DWARFDIE decl_ctx_die = GetDeclContextDIEContainingDIE(spec_die);
2656         if (decl_ctx_die)
2657           return decl_ctx_die;
2658       }
2659 
2660       DWARFDIE abs_die = die.GetReferencedDIE(DW_AT_abstract_origin);
2661       if (abs_die) {
2662         DWARFDIE decl_ctx_die = GetDeclContextDIEContainingDIE(abs_die);
2663         if (decl_ctx_die)
2664           return decl_ctx_die;
2665       }
2666 
2667       die = die.GetParent();
2668     }
2669   }
2670   return DWARFDIE();
2671 }
2672 
2673 Symbol *SymbolFileDWARF::GetObjCClassSymbol(ConstString objc_class_name) {
2674   Symbol *objc_class_symbol = nullptr;
2675   if (m_objfile_sp) {
2676     Symtab *symtab = m_objfile_sp->GetSymtab();
2677     if (symtab) {
2678       objc_class_symbol = symtab->FindFirstSymbolWithNameAndType(
2679           objc_class_name, eSymbolTypeObjCClass, Symtab::eDebugNo,
2680           Symtab::eVisibilityAny);
2681     }
2682   }
2683   return objc_class_symbol;
2684 }
2685 
2686 // Some compilers don't emit the DW_AT_APPLE_objc_complete_type attribute. If
2687 // they don't then we can end up looking through all class types for a complete
2688 // type and never find the full definition. We need to know if this attribute
2689 // is supported, so we determine this here and cache th result. We also need to
2690 // worry about the debug map
2691 // DWARF file
2692 // if we are doing darwin DWARF in .o file debugging.
2693 bool SymbolFileDWARF::Supports_DW_AT_APPLE_objc_complete_type(DWARFUnit *cu) {
2694   if (m_supports_DW_AT_APPLE_objc_complete_type == eLazyBoolCalculate) {
2695     m_supports_DW_AT_APPLE_objc_complete_type = eLazyBoolNo;
2696     if (cu && cu->Supports_DW_AT_APPLE_objc_complete_type())
2697       m_supports_DW_AT_APPLE_objc_complete_type = eLazyBoolYes;
2698     else {
2699       DWARFDebugInfo *debug_info = DebugInfo();
2700       const uint32_t num_compile_units = GetNumCompileUnits();
2701       for (uint32_t cu_idx = 0; cu_idx < num_compile_units; ++cu_idx) {
2702         DWARFUnit *dwarf_cu = debug_info->GetUnitAtIndex(cu_idx);
2703         if (dwarf_cu != cu &&
2704             dwarf_cu->Supports_DW_AT_APPLE_objc_complete_type()) {
2705           m_supports_DW_AT_APPLE_objc_complete_type = eLazyBoolYes;
2706           break;
2707         }
2708       }
2709     }
2710     if (m_supports_DW_AT_APPLE_objc_complete_type == eLazyBoolNo &&
2711         GetDebugMapSymfile())
2712       return m_debug_map_symfile->Supports_DW_AT_APPLE_objc_complete_type(this);
2713   }
2714   return m_supports_DW_AT_APPLE_objc_complete_type == eLazyBoolYes;
2715 }
2716 
2717 // This function can be used when a DIE is found that is a forward declaration
2718 // DIE and we want to try and find a type that has the complete definition.
2719 TypeSP SymbolFileDWARF::FindCompleteObjCDefinitionTypeForDIE(
2720     const DWARFDIE &die, ConstString type_name, bool must_be_implementation) {
2721 
2722   TypeSP type_sp;
2723 
2724   if (!type_name || (must_be_implementation && !GetObjCClassSymbol(type_name)))
2725     return type_sp;
2726 
2727   DIEArray die_offsets;
2728   m_index->GetCompleteObjCClass(type_name, must_be_implementation, die_offsets);
2729 
2730   const size_t num_matches = die_offsets.size();
2731 
2732   if (num_matches) {
2733     for (size_t i = 0; i < num_matches; ++i) {
2734       const DIERef &die_ref = die_offsets[i];
2735       DWARFDIE type_die = GetDIE(die_ref);
2736 
2737       if (type_die) {
2738         bool try_resolving_type = false;
2739 
2740         // Don't try and resolve the DIE we are looking for with the DIE
2741         // itself!
2742         if (type_die != die) {
2743           switch (type_die.Tag()) {
2744           case DW_TAG_class_type:
2745           case DW_TAG_structure_type:
2746             try_resolving_type = true;
2747             break;
2748           default:
2749             break;
2750           }
2751         }
2752 
2753         if (try_resolving_type) {
2754           if (must_be_implementation &&
2755               type_die.Supports_DW_AT_APPLE_objc_complete_type())
2756             try_resolving_type = type_die.GetAttributeValueAsUnsigned(
2757                 DW_AT_APPLE_objc_complete_type, 0);
2758 
2759           if (try_resolving_type) {
2760             Type *resolved_type = ResolveType(type_die, false, true);
2761             if (resolved_type && resolved_type != DIE_IS_BEING_PARSED) {
2762               DEBUG_PRINTF("resolved 0x%8.8" PRIx64 " from %s to 0x%8.8" PRIx64
2763                            " (cu 0x%8.8" PRIx64 ")\n",
2764                            die.GetID(),
2765                            m_objfile_sp->GetFileSpec().GetFilename().AsCString(
2766                                "<Unknown>"),
2767                            type_die.GetID(), type_cu->GetID());
2768 
2769               if (die)
2770                 GetDIEToType()[die.GetDIE()] = resolved_type;
2771               type_sp = resolved_type->shared_from_this();
2772               break;
2773             }
2774           }
2775         }
2776       } else {
2777         m_index->ReportInvalidDIERef(die_ref, type_name.GetStringRef());
2778       }
2779     }
2780   }
2781   return type_sp;
2782 }
2783 
2784 // This function helps to ensure that the declaration contexts match for two
2785 // different DIEs. Often times debug information will refer to a forward
2786 // declaration of a type (the equivalent of "struct my_struct;". There will
2787 // often be a declaration of that type elsewhere that has the full definition.
2788 // When we go looking for the full type "my_struct", we will find one or more
2789 // matches in the accelerator tables and we will then need to make sure the
2790 // type was in the same declaration context as the original DIE. This function
2791 // can efficiently compare two DIEs and will return true when the declaration
2792 // context matches, and false when they don't.
2793 bool SymbolFileDWARF::DIEDeclContextsMatch(const DWARFDIE &die1,
2794                                            const DWARFDIE &die2) {
2795   if (die1 == die2)
2796     return true;
2797 
2798   std::vector<DWARFDIE> decl_ctx_1;
2799   std::vector<DWARFDIE> decl_ctx_2;
2800   // The declaration DIE stack is a stack of the declaration context DIEs all
2801   // the way back to the compile unit. If a type "T" is declared inside a class
2802   // "B", and class "B" is declared inside a class "A" and class "A" is in a
2803   // namespace "lldb", and the namespace is in a compile unit, there will be a
2804   // stack of DIEs:
2805   //
2806   //   [0] DW_TAG_class_type for "B"
2807   //   [1] DW_TAG_class_type for "A"
2808   //   [2] DW_TAG_namespace  for "lldb"
2809   //   [3] DW_TAG_compile_unit or DW_TAG_partial_unit for the source file.
2810   //
2811   // We grab both contexts and make sure that everything matches all the way
2812   // back to the compiler unit.
2813 
2814   // First lets grab the decl contexts for both DIEs
2815   decl_ctx_1 = die1.GetDeclContextDIEs();
2816   decl_ctx_2 = die2.GetDeclContextDIEs();
2817   // Make sure the context arrays have the same size, otherwise we are done
2818   const size_t count1 = decl_ctx_1.size();
2819   const size_t count2 = decl_ctx_2.size();
2820   if (count1 != count2)
2821     return false;
2822 
2823   // Make sure the DW_TAG values match all the way back up the compile unit. If
2824   // they don't, then we are done.
2825   DWARFDIE decl_ctx_die1;
2826   DWARFDIE decl_ctx_die2;
2827   size_t i;
2828   for (i = 0; i < count1; i++) {
2829     decl_ctx_die1 = decl_ctx_1[i];
2830     decl_ctx_die2 = decl_ctx_2[i];
2831     if (decl_ctx_die1.Tag() != decl_ctx_die2.Tag())
2832       return false;
2833   }
2834 #ifndef NDEBUG
2835 
2836   // Make sure the top item in the decl context die array is always
2837   // DW_TAG_compile_unit or DW_TAG_partial_unit. If it isn't then
2838   // something went wrong in the DWARFDIE::GetDeclContextDIEs()
2839   // function.
2840   dw_tag_t cu_tag = decl_ctx_1[count1 - 1].Tag();
2841   UNUSED_IF_ASSERT_DISABLED(cu_tag);
2842   assert(cu_tag == DW_TAG_compile_unit || cu_tag == DW_TAG_partial_unit);
2843 
2844 #endif
2845   // Always skip the compile unit when comparing by only iterating up to "count
2846   // - 1". Here we compare the names as we go.
2847   for (i = 0; i < count1 - 1; i++) {
2848     decl_ctx_die1 = decl_ctx_1[i];
2849     decl_ctx_die2 = decl_ctx_2[i];
2850     const char *name1 = decl_ctx_die1.GetName();
2851     const char *name2 = decl_ctx_die2.GetName();
2852     // If the string was from a DW_FORM_strp, then the pointer will often be
2853     // the same!
2854     if (name1 == name2)
2855       continue;
2856 
2857     // Name pointers are not equal, so only compare the strings if both are not
2858     // NULL.
2859     if (name1 && name2) {
2860       // If the strings don't compare, we are done...
2861       if (strcmp(name1, name2) != 0)
2862         return false;
2863     } else {
2864       // One name was NULL while the other wasn't
2865       return false;
2866     }
2867   }
2868   // We made it through all of the checks and the declaration contexts are
2869   // equal.
2870   return true;
2871 }
2872 
2873 TypeSP SymbolFileDWARF::FindDefinitionTypeForDWARFDeclContext(
2874     const DWARFDeclContext &dwarf_decl_ctx) {
2875   TypeSP type_sp;
2876 
2877   const uint32_t dwarf_decl_ctx_count = dwarf_decl_ctx.GetSize();
2878   if (dwarf_decl_ctx_count > 0) {
2879     const ConstString type_name(dwarf_decl_ctx[0].name);
2880     const dw_tag_t tag = dwarf_decl_ctx[0].tag;
2881 
2882     if (type_name) {
2883       Log *log(LogChannelDWARF::GetLogIfAny(DWARF_LOG_TYPE_COMPLETION |
2884                                             DWARF_LOG_LOOKUPS));
2885       if (log) {
2886         GetObjectFile()->GetModule()->LogMessage(
2887             log,
2888             "SymbolFileDWARF::FindDefinitionTypeForDWARFDeclContext(tag=%"
2889             "s, qualified-name='%s')",
2890             DW_TAG_value_to_name(dwarf_decl_ctx[0].tag),
2891             dwarf_decl_ctx.GetQualifiedName());
2892       }
2893 
2894       DIEArray die_offsets;
2895       m_index->GetTypes(dwarf_decl_ctx, die_offsets);
2896       const size_t num_matches = die_offsets.size();
2897 
2898       // Get the type system that we are looking to find a type for. We will
2899       // use this to ensure any matches we find are in a language that this
2900       // type system supports
2901       const LanguageType language = dwarf_decl_ctx.GetLanguage();
2902       TypeSystem *type_system = nullptr;
2903       if (language != eLanguageTypeUnknown) {
2904         auto type_system_or_err = GetTypeSystemForLanguage(language);
2905         if (auto err = type_system_or_err.takeError()) {
2906           LLDB_LOG_ERROR(
2907               lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_SYMBOLS),
2908               std::move(err), "Cannot get TypeSystem for language {}",
2909               Language::GetNameForLanguageType(language));
2910         } else {
2911           type_system = &type_system_or_err.get();
2912         }
2913       }
2914       if (num_matches) {
2915         for (size_t i = 0; i < num_matches; ++i) {
2916           const DIERef &die_ref = die_offsets[i];
2917           DWARFDIE type_die = GetDIE(die_ref);
2918 
2919           if (type_die) {
2920             // Make sure type_die's langauge matches the type system we are
2921             // looking for. We don't want to find a "Foo" type from Java if we
2922             // are looking for a "Foo" type for C, C++, ObjC, or ObjC++.
2923             if (type_system &&
2924                 !type_system->SupportsLanguage(type_die.GetLanguage()))
2925               continue;
2926             bool try_resolving_type = false;
2927 
2928             // Don't try and resolve the DIE we are looking for with the DIE
2929             // itself!
2930             const dw_tag_t type_tag = type_die.Tag();
2931             // Make sure the tags match
2932             if (type_tag == tag) {
2933               // The tags match, lets try resolving this type
2934               try_resolving_type = true;
2935             } else {
2936               // The tags don't match, but we need to watch our for a forward
2937               // declaration for a struct and ("struct foo") ends up being a
2938               // class ("class foo { ... };") or vice versa.
2939               switch (type_tag) {
2940               case DW_TAG_class_type:
2941                 // We had a "class foo", see if we ended up with a "struct foo
2942                 // { ... };"
2943                 try_resolving_type = (tag == DW_TAG_structure_type);
2944                 break;
2945               case DW_TAG_structure_type:
2946                 // We had a "struct foo", see if we ended up with a "class foo
2947                 // { ... };"
2948                 try_resolving_type = (tag == DW_TAG_class_type);
2949                 break;
2950               default:
2951                 // Tags don't match, don't event try to resolve using this type
2952                 // whose name matches....
2953                 break;
2954               }
2955             }
2956 
2957             if (try_resolving_type) {
2958               DWARFDeclContext type_dwarf_decl_ctx;
2959               type_die.GetDWARFDeclContext(type_dwarf_decl_ctx);
2960 
2961               if (log) {
2962                 GetObjectFile()->GetModule()->LogMessage(
2963                     log,
2964                     "SymbolFileDWARF::"
2965                     "FindDefinitionTypeForDWARFDeclContext(tag=%s, "
2966                     "qualified-name='%s') trying die=0x%8.8x (%s)",
2967                     DW_TAG_value_to_name(dwarf_decl_ctx[0].tag),
2968                     dwarf_decl_ctx.GetQualifiedName(), type_die.GetOffset(),
2969                     type_dwarf_decl_ctx.GetQualifiedName());
2970               }
2971 
2972               // Make sure the decl contexts match all the way up
2973               if (dwarf_decl_ctx == type_dwarf_decl_ctx) {
2974                 Type *resolved_type = ResolveType(type_die, false);
2975                 if (resolved_type && resolved_type != DIE_IS_BEING_PARSED) {
2976                   type_sp = resolved_type->shared_from_this();
2977                   break;
2978                 }
2979               }
2980             } else {
2981               if (log) {
2982                 std::string qualified_name;
2983                 type_die.GetQualifiedName(qualified_name);
2984                 GetObjectFile()->GetModule()->LogMessage(
2985                     log,
2986                     "SymbolFileDWARF::"
2987                     "FindDefinitionTypeForDWARFDeclContext(tag=%s, "
2988                     "qualified-name='%s') ignoring die=0x%8.8x (%s)",
2989                     DW_TAG_value_to_name(dwarf_decl_ctx[0].tag),
2990                     dwarf_decl_ctx.GetQualifiedName(), type_die.GetOffset(),
2991                     qualified_name.c_str());
2992               }
2993             }
2994           } else {
2995             m_index->ReportInvalidDIERef(die_ref, type_name.GetStringRef());
2996           }
2997         }
2998       }
2999     }
3000   }
3001   return type_sp;
3002 }
3003 
3004 TypeSP SymbolFileDWARF::ParseType(const SymbolContext &sc, const DWARFDIE &die,
3005                                   bool *type_is_new_ptr) {
3006   if (!die)
3007     return {};
3008 
3009   auto type_system_or_err =
3010       GetTypeSystemForLanguage(die.GetCU()->GetLanguageType());
3011   if (auto err = type_system_or_err.takeError()) {
3012     LLDB_LOG_ERROR(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_SYMBOLS),
3013                    std::move(err), "Unable to parse type");
3014     return {};
3015   }
3016 
3017   DWARFASTParser *dwarf_ast = type_system_or_err->GetDWARFParser();
3018   if (!dwarf_ast)
3019     return {};
3020 
3021   TypeSP type_sp = dwarf_ast->ParseTypeFromDWARF(sc, die, type_is_new_ptr);
3022   if (type_sp) {
3023     GetTypeList().Insert(type_sp);
3024 
3025     if (die.Tag() == DW_TAG_subprogram) {
3026       std::string scope_qualified_name(GetDeclContextForUID(die.GetID())
3027                                            .GetScopeQualifiedName()
3028                                            .AsCString(""));
3029       if (scope_qualified_name.size()) {
3030         m_function_scope_qualified_name_map[scope_qualified_name].insert(
3031             die.GetID());
3032       }
3033     }
3034   }
3035 
3036   return type_sp;
3037 }
3038 
3039 size_t SymbolFileDWARF::ParseTypes(const SymbolContext &sc,
3040                                    const DWARFDIE &orig_die,
3041                                    bool parse_siblings, bool parse_children) {
3042   size_t types_added = 0;
3043   DWARFDIE die = orig_die;
3044 
3045   while (die) {
3046     const dw_tag_t tag = die.Tag();
3047     bool type_is_new = false;
3048 
3049     Tag dwarf_tag = static_cast<Tag>(tag);
3050 
3051     // TODO: Currently ParseTypeFromDWARF(...) which is called by ParseType(...)
3052     // does not handle DW_TAG_subrange_type. It is not clear if this is a bug or
3053     // not.
3054     if (isType(dwarf_tag) && tag != DW_TAG_subrange_type)
3055       ParseType(sc, die, &type_is_new);
3056 
3057     if (type_is_new)
3058       ++types_added;
3059 
3060     if (parse_children && die.HasChildren()) {
3061       if (die.Tag() == DW_TAG_subprogram) {
3062         SymbolContext child_sc(sc);
3063         child_sc.function = sc.comp_unit->FindFunctionByUID(die.GetID()).get();
3064         types_added += ParseTypes(child_sc, die.GetFirstChild(), true, true);
3065       } else
3066         types_added += ParseTypes(sc, die.GetFirstChild(), true, true);
3067     }
3068 
3069     if (parse_siblings)
3070       die = die.GetSibling();
3071     else
3072       die.Clear();
3073   }
3074   return types_added;
3075 }
3076 
3077 size_t SymbolFileDWARF::ParseBlocksRecursive(Function &func) {
3078   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
3079   CompileUnit *comp_unit = func.GetCompileUnit();
3080   lldbassert(comp_unit);
3081 
3082   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(comp_unit);
3083   if (!dwarf_cu)
3084     return 0;
3085 
3086   size_t functions_added = 0;
3087   const dw_offset_t function_die_offset = func.GetID();
3088   DWARFDIE function_die = dwarf_cu->GetDIE(function_die_offset);
3089   if (function_die) {
3090     ParseBlocksRecursive(*comp_unit, &func.GetBlock(false), function_die,
3091                          LLDB_INVALID_ADDRESS, 0);
3092   }
3093 
3094   return functions_added;
3095 }
3096 
3097 size_t SymbolFileDWARF::ParseTypes(CompileUnit &comp_unit) {
3098   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
3099   size_t types_added = 0;
3100   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(&comp_unit);
3101   if (dwarf_cu) {
3102     DWARFDIE dwarf_cu_die = dwarf_cu->DIE();
3103     if (dwarf_cu_die && dwarf_cu_die.HasChildren()) {
3104       SymbolContext sc;
3105       sc.comp_unit = &comp_unit;
3106       types_added = ParseTypes(sc, dwarf_cu_die.GetFirstChild(), true, true);
3107     }
3108   }
3109 
3110   return types_added;
3111 }
3112 
3113 size_t SymbolFileDWARF::ParseVariablesForContext(const SymbolContext &sc) {
3114   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
3115   if (sc.comp_unit != nullptr) {
3116     DWARFDebugInfo *info = DebugInfo();
3117     if (info == nullptr)
3118       return 0;
3119 
3120     if (sc.function) {
3121       DWARFDIE function_die = GetDIE(sc.function->GetID());
3122 
3123       const dw_addr_t func_lo_pc = function_die.GetAttributeValueAsAddress(
3124           DW_AT_low_pc, LLDB_INVALID_ADDRESS);
3125       if (func_lo_pc != LLDB_INVALID_ADDRESS) {
3126         const size_t num_variables = ParseVariables(
3127             sc, function_die.GetFirstChild(), func_lo_pc, true, true);
3128 
3129         // Let all blocks know they have parse all their variables
3130         sc.function->GetBlock(false).SetDidParseVariables(true, true);
3131         return num_variables;
3132       }
3133     } else if (sc.comp_unit) {
3134       DWARFUnit *dwarf_cu = info->GetUnitAtIndex(sc.comp_unit->GetID());
3135 
3136       if (dwarf_cu == nullptr)
3137         return 0;
3138 
3139       uint32_t vars_added = 0;
3140       VariableListSP variables(sc.comp_unit->GetVariableList(false));
3141 
3142       if (variables.get() == nullptr) {
3143         variables = std::make_shared<VariableList>();
3144         sc.comp_unit->SetVariableList(variables);
3145 
3146         DIEArray die_offsets;
3147         m_index->GetGlobalVariables(dwarf_cu->GetNonSkeletonUnit(),
3148                                     die_offsets);
3149         const size_t num_matches = die_offsets.size();
3150         if (num_matches) {
3151           for (size_t i = 0; i < num_matches; ++i) {
3152             const DIERef &die_ref = die_offsets[i];
3153             DWARFDIE die = GetDIE(die_ref);
3154             if (die) {
3155               VariableSP var_sp(
3156                   ParseVariableDIE(sc, die, LLDB_INVALID_ADDRESS));
3157               if (var_sp) {
3158                 variables->AddVariableIfUnique(var_sp);
3159                 ++vars_added;
3160               }
3161             } else
3162               m_index->ReportInvalidDIERef(die_ref, "");
3163           }
3164         }
3165       }
3166       return vars_added;
3167     }
3168   }
3169   return 0;
3170 }
3171 
3172 VariableSP SymbolFileDWARF::ParseVariableDIE(const SymbolContext &sc,
3173                                              const DWARFDIE &die,
3174                                              const lldb::addr_t func_low_pc) {
3175   if (die.GetDWARF() != this)
3176     return die.GetDWARF()->ParseVariableDIE(sc, die, func_low_pc);
3177 
3178   VariableSP var_sp;
3179   if (!die)
3180     return var_sp;
3181 
3182   var_sp = GetDIEToVariable()[die.GetDIE()];
3183   if (var_sp)
3184     return var_sp; // Already been parsed!
3185 
3186   const dw_tag_t tag = die.Tag();
3187   ModuleSP module = GetObjectFile()->GetModule();
3188 
3189   if ((tag == DW_TAG_variable) || (tag == DW_TAG_constant) ||
3190       (tag == DW_TAG_formal_parameter && sc.function)) {
3191     DWARFAttributes attributes;
3192     const size_t num_attributes = die.GetAttributes(attributes);
3193     DWARFDIE spec_die;
3194     if (num_attributes > 0) {
3195       const char *name = nullptr;
3196       const char *mangled = nullptr;
3197       Declaration decl;
3198       uint32_t i;
3199       DWARFFormValue type_die_form;
3200       DWARFExpression location;
3201       bool is_external = false;
3202       bool is_artificial = false;
3203       bool location_is_const_value_data = false;
3204       bool has_explicit_location = false;
3205       DWARFFormValue const_value;
3206       Variable::RangeList scope_ranges;
3207       // AccessType accessibility = eAccessNone;
3208 
3209       for (i = 0; i < num_attributes; ++i) {
3210         dw_attr_t attr = attributes.AttributeAtIndex(i);
3211         DWARFFormValue form_value;
3212 
3213         if (attributes.ExtractFormValueAtIndex(i, form_value)) {
3214           switch (attr) {
3215           case DW_AT_decl_file:
3216             decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
3217                 form_value.Unsigned()));
3218             break;
3219           case DW_AT_decl_line:
3220             decl.SetLine(form_value.Unsigned());
3221             break;
3222           case DW_AT_decl_column:
3223             decl.SetColumn(form_value.Unsigned());
3224             break;
3225           case DW_AT_name:
3226             name = form_value.AsCString();
3227             break;
3228           case DW_AT_linkage_name:
3229           case DW_AT_MIPS_linkage_name:
3230             mangled = form_value.AsCString();
3231             break;
3232           case DW_AT_type:
3233             type_die_form = form_value;
3234             break;
3235           case DW_AT_external:
3236             is_external = form_value.Boolean();
3237             break;
3238           case DW_AT_const_value:
3239             // If we have already found a DW_AT_location attribute, ignore this
3240             // attribute.
3241             if (!has_explicit_location) {
3242               location_is_const_value_data = true;
3243               // The constant value will be either a block, a data value or a
3244               // string.
3245               auto debug_info_data = die.GetData();
3246               if (DWARFFormValue::IsBlockForm(form_value.Form())) {
3247                 // Retrieve the value as a block expression.
3248                 uint32_t block_offset =
3249                     form_value.BlockData() - debug_info_data.GetDataStart();
3250                 uint32_t block_length = form_value.Unsigned();
3251                 location = DWARFExpression(
3252                     module,
3253                     DataExtractor(debug_info_data, block_offset, block_length),
3254                     die.GetCU());
3255               } else if (DWARFFormValue::IsDataForm(form_value.Form())) {
3256                 // Retrieve the value as a data expression.
3257                 uint32_t data_offset = attributes.DIEOffsetAtIndex(i);
3258                 if (auto data_length = form_value.GetFixedSize())
3259                   location = DWARFExpression(
3260                       module,
3261                       DataExtractor(debug_info_data, data_offset, *data_length),
3262                       die.GetCU());
3263                 else {
3264                   const uint8_t *data_pointer = form_value.BlockData();
3265                   if (data_pointer) {
3266                     form_value.Unsigned();
3267                   } else if (DWARFFormValue::IsDataForm(form_value.Form())) {
3268                     // we need to get the byte size of the type later after we
3269                     // create the variable
3270                     const_value = form_value;
3271                   }
3272                 }
3273               } else {
3274                 // Retrieve the value as a string expression.
3275                 if (form_value.Form() == DW_FORM_strp) {
3276                   uint32_t data_offset = attributes.DIEOffsetAtIndex(i);
3277                   if (auto data_length = form_value.GetFixedSize())
3278                     location = DWARFExpression(module,
3279                                                DataExtractor(debug_info_data,
3280                                                              data_offset,
3281                                                              *data_length),
3282                                                die.GetCU());
3283                 } else {
3284                   const char *str = form_value.AsCString();
3285                   uint32_t string_offset =
3286                       str - (const char *)debug_info_data.GetDataStart();
3287                   uint32_t string_length = strlen(str) + 1;
3288                   location = DWARFExpression(module,
3289                                              DataExtractor(debug_info_data,
3290                                                            string_offset,
3291                                                            string_length),
3292                                              die.GetCU());
3293                 }
3294               }
3295             }
3296             break;
3297           case DW_AT_location: {
3298             location_is_const_value_data = false;
3299             has_explicit_location = true;
3300             if (DWARFFormValue::IsBlockForm(form_value.Form())) {
3301               auto data = die.GetData();
3302 
3303               uint32_t block_offset =
3304                   form_value.BlockData() - data.GetDataStart();
3305               uint32_t block_length = form_value.Unsigned();
3306               location = DWARFExpression(
3307                   module, DataExtractor(data, block_offset, block_length),
3308                   die.GetCU());
3309             } else {
3310               DataExtractor data = DebugLocData();
3311               const dw_offset_t offset = form_value.Unsigned();
3312               if (data.ValidOffset(offset)) {
3313                 data = DataExtractor(data, offset, data.GetByteSize() - offset);
3314                 location = DWARFExpression(module, data, die.GetCU());
3315                 assert(func_low_pc != LLDB_INVALID_ADDRESS);
3316                 location.SetLocationListSlide(
3317                     func_low_pc -
3318                     attributes.CompileUnitAtIndex(i)->GetBaseAddress());
3319               }
3320             }
3321           } break;
3322           case DW_AT_specification:
3323             spec_die = form_value.Reference();
3324             break;
3325           case DW_AT_start_scope:
3326             // TODO: Implement this.
3327             break;
3328           case DW_AT_artificial:
3329             is_artificial = form_value.Boolean();
3330             break;
3331           case DW_AT_accessibility:
3332             break; // accessibility =
3333                    // DW_ACCESS_to_AccessType(form_value.Unsigned()); break;
3334           case DW_AT_declaration:
3335           case DW_AT_description:
3336           case DW_AT_endianity:
3337           case DW_AT_segment:
3338           case DW_AT_visibility:
3339           default:
3340           case DW_AT_abstract_origin:
3341           case DW_AT_sibling:
3342             break;
3343           }
3344         }
3345       }
3346 
3347       const DWARFDIE parent_context_die = GetDeclContextDIEContainingDIE(die);
3348       const dw_tag_t parent_tag = die.GetParent().Tag();
3349       bool is_static_member =
3350           (parent_tag == DW_TAG_compile_unit ||
3351            parent_tag == DW_TAG_partial_unit) &&
3352           (parent_context_die.Tag() == DW_TAG_class_type ||
3353            parent_context_die.Tag() == DW_TAG_structure_type);
3354 
3355       ValueType scope = eValueTypeInvalid;
3356 
3357       const DWARFDIE sc_parent_die = GetParentSymbolContextDIE(die);
3358       SymbolContextScope *symbol_context_scope = nullptr;
3359 
3360       bool has_explicit_mangled = mangled != nullptr;
3361       if (!mangled) {
3362         // LLDB relies on the mangled name (DW_TAG_linkage_name or
3363         // DW_AT_MIPS_linkage_name) to generate fully qualified names
3364         // of global variables with commands like "frame var j". For
3365         // example, if j were an int variable holding a value 4 and
3366         // declared in a namespace B which in turn is contained in a
3367         // namespace A, the command "frame var j" returns
3368         //   "(int) A::B::j = 4".
3369         // If the compiler does not emit a linkage name, we should be
3370         // able to generate a fully qualified name from the
3371         // declaration context.
3372         if ((parent_tag == DW_TAG_compile_unit ||
3373              parent_tag == DW_TAG_partial_unit) &&
3374             Language::LanguageIsCPlusPlus(die.GetLanguage())) {
3375           DWARFDeclContext decl_ctx;
3376 
3377           die.GetDWARFDeclContext(decl_ctx);
3378           mangled = decl_ctx.GetQualifiedNameAsConstString().GetCString();
3379         }
3380       }
3381 
3382       if (tag == DW_TAG_formal_parameter)
3383         scope = eValueTypeVariableArgument;
3384       else {
3385         // DWARF doesn't specify if a DW_TAG_variable is a local, global
3386         // or static variable, so we have to do a little digging:
3387         // 1) DW_AT_linkage_name implies static lifetime (but may be missing)
3388         // 2) An empty DW_AT_location is an (optimized-out) static lifetime var.
3389         // 3) DW_AT_location containing a DW_OP_addr implies static lifetime.
3390         // Clang likes to combine small global variables into the same symbol
3391         // with locations like: DW_OP_addr(0x1000), DW_OP_constu(2), DW_OP_plus
3392         // so we need to look through the whole expression.
3393         bool is_static_lifetime =
3394             has_explicit_mangled ||
3395             (has_explicit_location && !location.IsValid());
3396         // Check if the location has a DW_OP_addr with any address value...
3397         lldb::addr_t location_DW_OP_addr = LLDB_INVALID_ADDRESS;
3398         if (!location_is_const_value_data) {
3399           bool op_error = false;
3400           location_DW_OP_addr = location.GetLocation_DW_OP_addr(0, op_error);
3401           if (op_error) {
3402             StreamString strm;
3403             location.DumpLocationForAddress(&strm, eDescriptionLevelFull, 0, 0,
3404                                             nullptr);
3405             GetObjectFile()->GetModule()->ReportError(
3406                 "0x%8.8x: %s has an invalid location: %s", die.GetOffset(),
3407                 die.GetTagAsCString(), strm.GetData());
3408           }
3409           if (location_DW_OP_addr != LLDB_INVALID_ADDRESS)
3410             is_static_lifetime = true;
3411         }
3412         SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
3413         if (debug_map_symfile)
3414           // Set the module of the expression to the linked module
3415           // instead of the oject file so the relocated address can be
3416           // found there.
3417           location.SetModule(debug_map_symfile->GetObjectFile()->GetModule());
3418 
3419         if (is_static_lifetime) {
3420           if (is_external)
3421             scope = eValueTypeVariableGlobal;
3422           else
3423             scope = eValueTypeVariableStatic;
3424 
3425           if (debug_map_symfile) {
3426             // When leaving the DWARF in the .o files on darwin, when we have a
3427             // global variable that wasn't initialized, the .o file might not
3428             // have allocated a virtual address for the global variable. In
3429             // this case it will have created a symbol for the global variable
3430             // that is undefined/data and external and the value will be the
3431             // byte size of the variable. When we do the address map in
3432             // SymbolFileDWARFDebugMap we rely on having an address, we need to
3433             // do some magic here so we can get the correct address for our
3434             // global variable. The address for all of these entries will be
3435             // zero, and there will be an undefined symbol in this object file,
3436             // and the executable will have a matching symbol with a good
3437             // address. So here we dig up the correct address and replace it in
3438             // the location for the variable, and set the variable's symbol
3439             // context scope to be that of the main executable so the file
3440             // address will resolve correctly.
3441             bool linked_oso_file_addr = false;
3442             if (is_external && location_DW_OP_addr == 0) {
3443               // we have a possible uninitialized extern global
3444               ConstString const_name(mangled ? mangled : name);
3445               ObjectFile *debug_map_objfile =
3446                   debug_map_symfile->GetObjectFile();
3447               if (debug_map_objfile) {
3448                 Symtab *debug_map_symtab = debug_map_objfile->GetSymtab();
3449                 if (debug_map_symtab) {
3450                   Symbol *exe_symbol =
3451                       debug_map_symtab->FindFirstSymbolWithNameAndType(
3452                           const_name, eSymbolTypeData, Symtab::eDebugYes,
3453                           Symtab::eVisibilityExtern);
3454                   if (exe_symbol) {
3455                     if (exe_symbol->ValueIsAddress()) {
3456                       const addr_t exe_file_addr =
3457                           exe_symbol->GetAddressRef().GetFileAddress();
3458                       if (exe_file_addr != LLDB_INVALID_ADDRESS) {
3459                         if (location.Update_DW_OP_addr(exe_file_addr)) {
3460                           linked_oso_file_addr = true;
3461                           symbol_context_scope = exe_symbol;
3462                         }
3463                       }
3464                     }
3465                   }
3466                 }
3467               }
3468             }
3469 
3470             if (!linked_oso_file_addr) {
3471               // The DW_OP_addr is not zero, but it contains a .o file address
3472               // which needs to be linked up correctly.
3473               const lldb::addr_t exe_file_addr =
3474                   debug_map_symfile->LinkOSOFileAddress(this,
3475                                                         location_DW_OP_addr);
3476               if (exe_file_addr != LLDB_INVALID_ADDRESS) {
3477                 // Update the file address for this variable
3478                 location.Update_DW_OP_addr(exe_file_addr);
3479               } else {
3480                 // Variable didn't make it into the final executable
3481                 return var_sp;
3482               }
3483             }
3484           }
3485         } else {
3486           if (location_is_const_value_data)
3487             scope = eValueTypeVariableStatic;
3488           else {
3489             scope = eValueTypeVariableLocal;
3490             if (debug_map_symfile) {
3491               // We need to check for TLS addresses that we need to fixup
3492               if (location.ContainsThreadLocalStorage()) {
3493                 location.LinkThreadLocalStorage(
3494                     debug_map_symfile->GetObjectFile()->GetModule(),
3495                     [this, debug_map_symfile](
3496                         lldb::addr_t unlinked_file_addr) -> lldb::addr_t {
3497                       return debug_map_symfile->LinkOSOFileAddress(
3498                           this, unlinked_file_addr);
3499                     });
3500                 scope = eValueTypeVariableThreadLocal;
3501               }
3502             }
3503           }
3504         }
3505       }
3506 
3507       if (symbol_context_scope == nullptr) {
3508         switch (parent_tag) {
3509         case DW_TAG_subprogram:
3510         case DW_TAG_inlined_subroutine:
3511         case DW_TAG_lexical_block:
3512           if (sc.function) {
3513             symbol_context_scope = sc.function->GetBlock(true).FindBlockByID(
3514                 sc_parent_die.GetID());
3515             if (symbol_context_scope == nullptr)
3516               symbol_context_scope = sc.function;
3517           }
3518           break;
3519 
3520         default:
3521           symbol_context_scope = sc.comp_unit;
3522           break;
3523         }
3524       }
3525 
3526       if (symbol_context_scope) {
3527         SymbolFileTypeSP type_sp(
3528             new SymbolFileType(*this, GetUID(type_die_form.Reference())));
3529 
3530         if (const_value.Form() && type_sp && type_sp->GetType())
3531           location.UpdateValue(const_value.Unsigned(),
3532                                type_sp->GetType()->GetByteSize().getValueOr(0),
3533                                die.GetCU()->GetAddressByteSize());
3534 
3535         var_sp = std::make_shared<Variable>(
3536             die.GetID(), name, mangled, type_sp, scope, symbol_context_scope,
3537             scope_ranges, &decl, location, is_external, is_artificial,
3538             is_static_member);
3539 
3540         var_sp->SetLocationIsConstantValueData(location_is_const_value_data);
3541       } else {
3542         // Not ready to parse this variable yet. It might be a global or static
3543         // variable that is in a function scope and the function in the symbol
3544         // context wasn't filled in yet
3545         return var_sp;
3546       }
3547     }
3548     // Cache var_sp even if NULL (the variable was just a specification or was
3549     // missing vital information to be able to be displayed in the debugger
3550     // (missing location due to optimization, etc)) so we don't re-parse this
3551     // DIE over and over later...
3552     GetDIEToVariable()[die.GetDIE()] = var_sp;
3553     if (spec_die)
3554       GetDIEToVariable()[spec_die.GetDIE()] = var_sp;
3555   }
3556   return var_sp;
3557 }
3558 
3559 DWARFDIE
3560 SymbolFileDWARF::FindBlockContainingSpecification(
3561     const DIERef &func_die_ref, dw_offset_t spec_block_die_offset) {
3562   // Give the concrete function die specified by "func_die_offset", find the
3563   // concrete block whose DW_AT_specification or DW_AT_abstract_origin points
3564   // to "spec_block_die_offset"
3565   return FindBlockContainingSpecification(DebugInfo()->GetDIE(func_die_ref),
3566                                           spec_block_die_offset);
3567 }
3568 
3569 DWARFDIE
3570 SymbolFileDWARF::FindBlockContainingSpecification(
3571     const DWARFDIE &die, dw_offset_t spec_block_die_offset) {
3572   if (die) {
3573     switch (die.Tag()) {
3574     case DW_TAG_subprogram:
3575     case DW_TAG_inlined_subroutine:
3576     case DW_TAG_lexical_block: {
3577       if (die.GetReferencedDIE(DW_AT_specification).GetOffset() ==
3578           spec_block_die_offset)
3579         return die;
3580 
3581       if (die.GetReferencedDIE(DW_AT_abstract_origin).GetOffset() ==
3582           spec_block_die_offset)
3583         return die;
3584     } break;
3585     default:
3586       break;
3587     }
3588 
3589     // Give the concrete function die specified by "func_die_offset", find the
3590     // concrete block whose DW_AT_specification or DW_AT_abstract_origin points
3591     // to "spec_block_die_offset"
3592     for (DWARFDIE child_die = die.GetFirstChild(); child_die;
3593          child_die = child_die.GetSibling()) {
3594       DWARFDIE result_die =
3595           FindBlockContainingSpecification(child_die, spec_block_die_offset);
3596       if (result_die)
3597         return result_die;
3598     }
3599   }
3600 
3601   return DWARFDIE();
3602 }
3603 
3604 size_t SymbolFileDWARF::ParseVariables(const SymbolContext &sc,
3605                                        const DWARFDIE &orig_die,
3606                                        const lldb::addr_t func_low_pc,
3607                                        bool parse_siblings, bool parse_children,
3608                                        VariableList *cc_variable_list) {
3609   if (!orig_die)
3610     return 0;
3611 
3612   VariableListSP variable_list_sp;
3613 
3614   size_t vars_added = 0;
3615   DWARFDIE die = orig_die;
3616   while (die) {
3617     dw_tag_t tag = die.Tag();
3618 
3619     // Check to see if we have already parsed this variable or constant?
3620     VariableSP var_sp = GetDIEToVariable()[die.GetDIE()];
3621     if (var_sp) {
3622       if (cc_variable_list)
3623         cc_variable_list->AddVariableIfUnique(var_sp);
3624     } else {
3625       // We haven't already parsed it, lets do that now.
3626       if ((tag == DW_TAG_variable) || (tag == DW_TAG_constant) ||
3627           (tag == DW_TAG_formal_parameter && sc.function)) {
3628         if (variable_list_sp.get() == nullptr) {
3629           DWARFDIE sc_parent_die = GetParentSymbolContextDIE(orig_die);
3630           dw_tag_t parent_tag = sc_parent_die.Tag();
3631           switch (parent_tag) {
3632           case DW_TAG_compile_unit:
3633           case DW_TAG_partial_unit:
3634             if (sc.comp_unit != nullptr) {
3635               variable_list_sp = sc.comp_unit->GetVariableList(false);
3636               if (variable_list_sp.get() == nullptr) {
3637                 variable_list_sp = std::make_shared<VariableList>();
3638               }
3639             } else {
3640               GetObjectFile()->GetModule()->ReportError(
3641                   "parent 0x%8.8" PRIx64 " %s with no valid compile unit in "
3642                   "symbol context for 0x%8.8" PRIx64 " %s.\n",
3643                   sc_parent_die.GetID(), sc_parent_die.GetTagAsCString(),
3644                   orig_die.GetID(), orig_die.GetTagAsCString());
3645             }
3646             break;
3647 
3648           case DW_TAG_subprogram:
3649           case DW_TAG_inlined_subroutine:
3650           case DW_TAG_lexical_block:
3651             if (sc.function != nullptr) {
3652               // Check to see if we already have parsed the variables for the
3653               // given scope
3654 
3655               Block *block = sc.function->GetBlock(true).FindBlockByID(
3656                   sc_parent_die.GetID());
3657               if (block == nullptr) {
3658                 // This must be a specification or abstract origin with a
3659                 // concrete block counterpart in the current function. We need
3660                 // to find the concrete block so we can correctly add the
3661                 // variable to it
3662                 const DWARFDIE concrete_block_die =
3663                     FindBlockContainingSpecification(
3664                         GetDIE(sc.function->GetID()),
3665                         sc_parent_die.GetOffset());
3666                 if (concrete_block_die)
3667                   block = sc.function->GetBlock(true).FindBlockByID(
3668                       concrete_block_die.GetID());
3669               }
3670 
3671               if (block != nullptr) {
3672                 const bool can_create = false;
3673                 variable_list_sp = block->GetBlockVariableList(can_create);
3674                 if (variable_list_sp.get() == nullptr) {
3675                   variable_list_sp = std::make_shared<VariableList>();
3676                   block->SetVariableList(variable_list_sp);
3677                 }
3678               }
3679             }
3680             break;
3681 
3682           default:
3683             GetObjectFile()->GetModule()->ReportError(
3684                 "didn't find appropriate parent DIE for variable list for "
3685                 "0x%8.8" PRIx64 " %s.\n",
3686                 orig_die.GetID(), orig_die.GetTagAsCString());
3687             break;
3688           }
3689         }
3690 
3691         if (variable_list_sp) {
3692           VariableSP var_sp(ParseVariableDIE(sc, die, func_low_pc));
3693           if (var_sp) {
3694             variable_list_sp->AddVariableIfUnique(var_sp);
3695             if (cc_variable_list)
3696               cc_variable_list->AddVariableIfUnique(var_sp);
3697             ++vars_added;
3698           }
3699         }
3700       }
3701     }
3702 
3703     bool skip_children = (sc.function == nullptr && tag == DW_TAG_subprogram);
3704 
3705     if (!skip_children && parse_children && die.HasChildren()) {
3706       vars_added += ParseVariables(sc, die.GetFirstChild(), func_low_pc, true,
3707                                    true, cc_variable_list);
3708     }
3709 
3710     if (parse_siblings)
3711       die = die.GetSibling();
3712     else
3713       die.Clear();
3714   }
3715   return vars_added;
3716 }
3717 
3718 /// Collect call site parameters in a DW_TAG_call_site DIE.
3719 static CallSiteParameterArray
3720 CollectCallSiteParameters(ModuleSP module, DWARFDIE call_site_die) {
3721   CallSiteParameterArray parameters;
3722   for (DWARFDIE child = call_site_die.GetFirstChild(); child.IsValid();
3723        child = child.GetSibling()) {
3724     if (child.Tag() != DW_TAG_call_site_parameter)
3725       continue;
3726 
3727     llvm::Optional<DWARFExpression> LocationInCallee = {};
3728     llvm::Optional<DWARFExpression> LocationInCaller = {};
3729 
3730     DWARFAttributes attributes;
3731     const size_t num_attributes = child.GetAttributes(attributes);
3732 
3733     // Parse the location at index \p attr_index within this call site parameter
3734     // DIE, or return None on failure.
3735     auto parse_simple_location =
3736         [&](int attr_index) -> llvm::Optional<DWARFExpression> {
3737       DWARFFormValue form_value;
3738       if (!attributes.ExtractFormValueAtIndex(attr_index, form_value))
3739         return {};
3740       if (!DWARFFormValue::IsBlockForm(form_value.Form()))
3741         return {};
3742       auto data = child.GetData();
3743       uint32_t block_offset = form_value.BlockData() - data.GetDataStart();
3744       uint32_t block_length = form_value.Unsigned();
3745       return DWARFExpression(module,
3746                              DataExtractor(data, block_offset, block_length),
3747                              child.GetCU());
3748     };
3749 
3750     for (size_t i = 0; i < num_attributes; ++i) {
3751       dw_attr_t attr = attributes.AttributeAtIndex(i);
3752       if (attr == DW_AT_location)
3753         LocationInCallee = parse_simple_location(i);
3754       if (attr == DW_AT_call_value)
3755         LocationInCaller = parse_simple_location(i);
3756     }
3757 
3758     if (LocationInCallee && LocationInCaller) {
3759       CallSiteParameter param = {*LocationInCallee, *LocationInCaller};
3760       parameters.push_back(param);
3761     }
3762   }
3763   return parameters;
3764 }
3765 
3766 /// Collect call graph edges present in a function DIE.
3767 static std::vector<lldb_private::CallEdge>
3768 CollectCallEdges(ModuleSP module, DWARFDIE function_die) {
3769   // Check if the function has a supported call site-related attribute.
3770   // TODO: In the future it may be worthwhile to support call_all_source_calls.
3771   uint64_t has_call_edges =
3772       function_die.GetAttributeValueAsUnsigned(DW_AT_call_all_calls, 0);
3773   if (!has_call_edges)
3774     return {};
3775 
3776   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
3777   LLDB_LOG(log, "CollectCallEdges: Found call site info in {0}",
3778            function_die.GetPubname());
3779 
3780   // Scan the DIE for TAG_call_site entries.
3781   // TODO: A recursive scan of all blocks in the subprogram is needed in order
3782   // to be DWARF5-compliant. This may need to be done lazily to be performant.
3783   // For now, assume that all entries are nested directly under the subprogram
3784   // (this is the kind of DWARF LLVM produces) and parse them eagerly.
3785   std::vector<CallEdge> call_edges;
3786   for (DWARFDIE child = function_die.GetFirstChild(); child.IsValid();
3787        child = child.GetSibling()) {
3788     if (child.Tag() != DW_TAG_call_site)
3789       continue;
3790 
3791     // Extract DW_AT_call_origin (the call target's DIE).
3792     DWARFDIE call_origin = child.GetReferencedDIE(DW_AT_call_origin);
3793     if (!call_origin.IsValid()) {
3794       LLDB_LOG(log, "CollectCallEdges: Invalid call origin in {0}",
3795                function_die.GetPubname());
3796       continue;
3797     }
3798 
3799     // Extract DW_AT_call_return_pc (the PC the call returns to) if it's
3800     // available. It should only ever be unavailable for tail call edges, in
3801     // which case use LLDB_INVALID_ADDRESS.
3802     addr_t return_pc = child.GetAttributeValueAsAddress(DW_AT_call_return_pc,
3803                                                         LLDB_INVALID_ADDRESS);
3804 
3805     // Extract call site parameters.
3806     CallSiteParameterArray parameters =
3807         CollectCallSiteParameters(module, child);
3808 
3809     LLDB_LOG(log, "CollectCallEdges: Found call origin: {0} (retn-PC: {1:x})",
3810              call_origin.GetPubname(), return_pc);
3811     if (log && parameters.size()) {
3812       for (const CallSiteParameter &param : parameters) {
3813         StreamString callee_loc_desc, caller_loc_desc;
3814         param.LocationInCallee.GetDescription(&callee_loc_desc,
3815                                               eDescriptionLevelBrief,
3816                                               LLDB_INVALID_ADDRESS, nullptr);
3817         param.LocationInCaller.GetDescription(&caller_loc_desc,
3818                                               eDescriptionLevelBrief,
3819                                               LLDB_INVALID_ADDRESS, nullptr);
3820         LLDB_LOG(log, "CollectCallEdges: \tparam: {0} => {1}",
3821                  callee_loc_desc.GetString(), caller_loc_desc.GetString());
3822       }
3823     }
3824 
3825     call_edges.emplace_back(call_origin.GetMangledName(), return_pc,
3826                             std::move(parameters));
3827   }
3828   return call_edges;
3829 }
3830 
3831 std::vector<lldb_private::CallEdge>
3832 SymbolFileDWARF::ParseCallEdgesInFunction(UserID func_id) {
3833   DWARFDIE func_die = GetDIE(func_id.GetID());
3834   if (func_die.IsValid())
3835     return CollectCallEdges(GetObjectFile()->GetModule(), func_die);
3836   return {};
3837 }
3838 
3839 // PluginInterface protocol
3840 ConstString SymbolFileDWARF::GetPluginName() { return GetPluginNameStatic(); }
3841 
3842 uint32_t SymbolFileDWARF::GetPluginVersion() { return 1; }
3843 
3844 void SymbolFileDWARF::Dump(lldb_private::Stream &s) {
3845   SymbolFile::Dump(s);
3846   m_index->Dump(s);
3847 }
3848 
3849 void SymbolFileDWARF::DumpClangAST(Stream &s) {
3850   auto ts_or_err = GetTypeSystemForLanguage(eLanguageTypeC_plus_plus);
3851   if (!ts_or_err)
3852     return;
3853   ClangASTContext *clang =
3854       llvm::dyn_cast_or_null<ClangASTContext>(&ts_or_err.get());
3855   if (!clang)
3856     return;
3857   clang->Dump(s);
3858 }
3859 
3860 SymbolFileDWARFDebugMap *SymbolFileDWARF::GetDebugMapSymfile() {
3861   if (m_debug_map_symfile == nullptr && !m_debug_map_module_wp.expired()) {
3862     lldb::ModuleSP module_sp(m_debug_map_module_wp.lock());
3863     if (module_sp) {
3864       m_debug_map_symfile =
3865           (SymbolFileDWARFDebugMap *)module_sp->GetSymbolFile();
3866     }
3867   }
3868   return m_debug_map_symfile;
3869 }
3870 
3871 DWARFExpression::LocationListFormat
3872 SymbolFileDWARF::GetLocationListFormat() const {
3873   if (m_data_debug_loclists.m_data.GetByteSize() > 0)
3874     return DWARFExpression::LocLists;
3875   return DWARFExpression::RegularLocationList;
3876 }
3877 
3878 SymbolFileDWARFDwp *SymbolFileDWARF::GetDwpSymbolFile() {
3879   llvm::call_once(m_dwp_symfile_once_flag, [this]() {
3880     ModuleSpec module_spec;
3881     module_spec.GetFileSpec() = m_objfile_sp->GetFileSpec();
3882     module_spec.GetSymbolFileSpec() =
3883         FileSpec(m_objfile_sp->GetFileSpec().GetPath() + ".dwp");
3884 
3885     FileSpecList search_paths = Target::GetDefaultDebugFileSearchPaths();
3886     FileSpec dwp_filespec =
3887         Symbols::LocateExecutableSymbolFile(module_spec, search_paths);
3888     if (FileSystem::Instance().Exists(dwp_filespec)) {
3889       m_dwp_symfile = SymbolFileDWARFDwp::Create(GetObjectFile()->GetModule(),
3890                                                  dwp_filespec);
3891     }
3892   });
3893   return m_dwp_symfile.get();
3894 }
3895