1 //===-- SymbolFileDWARF.cpp ------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "SymbolFileDWARF.h"
11 
12 // Other libraries and framework includes
13 #include "llvm/Support/Casting.h"
14 #include "llvm/Support/Threading.h"
15 
16 #include "lldb/Core/Module.h"
17 #include "lldb/Core/ModuleList.h"
18 #include "lldb/Core/ModuleSpec.h"
19 #include "lldb/Core/PluginManager.h"
20 #include "lldb/Core/Section.h"
21 #include "lldb/Core/StreamFile.h"
22 #include "lldb/Core/Value.h"
23 #include "lldb/Utility/ArchSpec.h"
24 #include "lldb/Utility/RegularExpression.h"
25 #include "lldb/Utility/Scalar.h"
26 #include "lldb/Utility/StreamString.h"
27 #include "lldb/Utility/Timer.h"
28 
29 #include "Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.h"
30 #include "Plugins/Language/CPlusPlus/CPlusPlusLanguage.h"
31 
32 #include "lldb/Host/FileSystem.h"
33 #include "lldb/Host/Host.h"
34 #include "lldb/Host/Symbols.h"
35 
36 #include "lldb/Interpreter/OptionValueFileSpecList.h"
37 #include "lldb/Interpreter/OptionValueProperties.h"
38 
39 #include "lldb/Symbol/Block.h"
40 #include "lldb/Symbol/ClangASTContext.h"
41 #include "lldb/Symbol/ClangUtil.h"
42 #include "lldb/Symbol/CompileUnit.h"
43 #include "lldb/Symbol/CompilerDecl.h"
44 #include "lldb/Symbol/CompilerDeclContext.h"
45 #include "lldb/Symbol/DebugMacros.h"
46 #include "lldb/Symbol/LineTable.h"
47 #include "lldb/Symbol/ObjectFile.h"
48 #include "lldb/Symbol/SymbolVendor.h"
49 #include "lldb/Symbol/TypeMap.h"
50 #include "lldb/Symbol/TypeSystem.h"
51 #include "lldb/Symbol/VariableList.h"
52 
53 #include "lldb/Target/Language.h"
54 
55 #include "AppleDWARFIndex.h"
56 #include "DWARFASTParser.h"
57 #include "DWARFASTParserClang.h"
58 #include "DWARFDIECollection.h"
59 #include "DWARFDebugAbbrev.h"
60 #include "DWARFDebugAranges.h"
61 #include "DWARFDebugInfo.h"
62 #include "DWARFDebugLine.h"
63 #include "DWARFDebugMacro.h"
64 #include "DWARFDebugRanges.h"
65 #include "DWARFDeclContext.h"
66 #include "DWARFFormValue.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/Support/FileSystem.h"
76 
77 #include <map>
78 
79 #include <ctype.h>
80 #include <string.h>
81 
82 //#define ENABLE_DEBUG_PRINTF // COMMENT OUT THIS LINE PRIOR TO CHECKIN
83 
84 #ifdef ENABLE_DEBUG_PRINTF
85 #include <stdio.h>
86 #define DEBUG_PRINTF(fmt, ...) printf(fmt, __VA_ARGS__)
87 #else
88 #define DEBUG_PRINTF(fmt, ...)
89 #endif
90 
91 using namespace lldb;
92 using namespace lldb_private;
93 
94 // static inline bool
95 // child_requires_parent_class_union_or_struct_to_be_completed (dw_tag_t tag)
96 //{
97 //    switch (tag)
98 //    {
99 //    default:
100 //        break;
101 //    case DW_TAG_subprogram:
102 //    case DW_TAG_inlined_subroutine:
103 //    case DW_TAG_class_type:
104 //    case DW_TAG_structure_type:
105 //    case DW_TAG_union_type:
106 //        return true;
107 //    }
108 //    return false;
109 //}
110 //
111 
112 namespace {
113 
114 static constexpr PropertyDefinition g_properties[] = {
115     {"comp-dir-symlink-paths", OptionValue::eTypeFileSpecList, true, 0, nullptr,
116      {},
117      "If the DW_AT_comp_dir matches any of these paths the symbolic "
118      "links will be resolved at DWARF parse time."},
119     {"ignore-file-indexes", OptionValue::eTypeBoolean, true, 0, nullptr, {},
120      "Ignore indexes present in the object files and always index DWARF "
121      "manually."}};
122 
123 enum {
124   ePropertySymLinkPaths,
125   ePropertyIgnoreIndexes,
126 };
127 
128 class PluginProperties : public Properties {
129 public:
130   static ConstString GetSettingName() {
131     return SymbolFileDWARF::GetPluginNameStatic();
132   }
133 
134   PluginProperties() {
135     m_collection_sp.reset(new OptionValueProperties(GetSettingName()));
136     m_collection_sp->Initialize(g_properties);
137   }
138 
139   FileSpecList &GetSymLinkPaths() {
140     OptionValueFileSpecList *option_value =
141         m_collection_sp->GetPropertyAtIndexAsOptionValueFileSpecList(
142             nullptr, true, ePropertySymLinkPaths);
143     assert(option_value);
144     return option_value->GetCurrentValue();
145   }
146 
147   bool IgnoreFileIndexes() const {
148     return m_collection_sp->GetPropertyAtIndexAsBoolean(
149         nullptr, ePropertyIgnoreIndexes, false);
150   }
151 };
152 
153 typedef std::shared_ptr<PluginProperties> SymbolFileDWARFPropertiesSP;
154 
155 static const SymbolFileDWARFPropertiesSP &GetGlobalPluginProperties() {
156   static const auto g_settings_sp(std::make_shared<PluginProperties>());
157   return g_settings_sp;
158 }
159 
160 } // anonymous namespace end
161 
162 static const char *removeHostnameFromPathname(const char *path_from_dwarf) {
163   if (!path_from_dwarf || !path_from_dwarf[0]) {
164     return path_from_dwarf;
165   }
166 
167   const char *colon_pos = strchr(path_from_dwarf, ':');
168   if (nullptr == colon_pos) {
169     return path_from_dwarf;
170   }
171 
172   const char *slash_pos = strchr(path_from_dwarf, '/');
173   if (slash_pos && (slash_pos < colon_pos)) {
174     return path_from_dwarf;
175   }
176 
177   // check whether we have a windows path, and so the first character is a
178   // drive-letter not a hostname.
179   if (colon_pos == path_from_dwarf + 1 && isalpha(*path_from_dwarf) &&
180       strlen(path_from_dwarf) > 2 && '\\' == path_from_dwarf[2]) {
181     return path_from_dwarf;
182   }
183 
184   return colon_pos + 1;
185 }
186 
187 static FileSpec resolveCompDir(const char *path_from_dwarf) {
188   if (!path_from_dwarf)
189     return FileSpec();
190 
191   // DWARF2/3 suggests the form hostname:pathname for compilation directory.
192   // Remove the host part if present.
193   const char *local_path = removeHostnameFromPathname(path_from_dwarf);
194   if (!local_path)
195     return FileSpec();
196 
197   bool is_symlink = false;
198   // Always normalize our compile unit directory to get rid of redundant
199   // slashes and other path anomalies before we use it for path prepending
200   FileSpec local_spec(local_path, false);
201   const auto &file_specs = GetGlobalPluginProperties()->GetSymLinkPaths();
202   for (size_t i = 0; i < file_specs.GetSize() && !is_symlink; ++i)
203     is_symlink = FileSpec::Equal(file_specs.GetFileSpecAtIndex(i),
204                                  local_spec, true);
205 
206   if (!is_symlink)
207     return local_spec;
208 
209   namespace fs = llvm::sys::fs;
210   if (fs::get_file_type(local_spec.GetPath(), false) !=
211       fs::file_type::symlink_file)
212     return local_spec;
213 
214   FileSpec resolved_symlink;
215   const auto error = FileSystem::Readlink(local_spec, resolved_symlink);
216   if (error.Success())
217     return resolved_symlink;
218 
219   return local_spec;
220 }
221 
222 DWARFUnit *SymbolFileDWARF::GetBaseCompileUnit() {
223   return nullptr;
224 }
225 
226 void SymbolFileDWARF::Initialize() {
227   LogChannelDWARF::Initialize();
228   PluginManager::RegisterPlugin(GetPluginNameStatic(),
229                                 GetPluginDescriptionStatic(), CreateInstance,
230                                 DebuggerInitialize);
231 }
232 
233 void SymbolFileDWARF::DebuggerInitialize(Debugger &debugger) {
234   if (!PluginManager::GetSettingForSymbolFilePlugin(
235           debugger, PluginProperties::GetSettingName())) {
236     const bool is_global_setting = true;
237     PluginManager::CreateSettingForSymbolFilePlugin(
238         debugger, GetGlobalPluginProperties()->GetValueProperties(),
239         ConstString("Properties for the dwarf symbol-file plug-in."),
240         is_global_setting);
241   }
242 }
243 
244 void SymbolFileDWARF::Terminate() {
245   PluginManager::UnregisterPlugin(CreateInstance);
246   LogChannelDWARF::Terminate();
247 }
248 
249 lldb_private::ConstString SymbolFileDWARF::GetPluginNameStatic() {
250   static ConstString g_name("dwarf");
251   return g_name;
252 }
253 
254 const char *SymbolFileDWARF::GetPluginDescriptionStatic() {
255   return "DWARF and DWARF3 debug symbol file reader.";
256 }
257 
258 SymbolFile *SymbolFileDWARF::CreateInstance(ObjectFile *obj_file) {
259   return new SymbolFileDWARF(obj_file);
260 }
261 
262 TypeList *SymbolFileDWARF::GetTypeList() {
263   // This method can be called without going through the symbol vendor so we
264   // need to lock the module.
265   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
266   SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
267   if (debug_map_symfile)
268     return debug_map_symfile->GetTypeList();
269   else
270     return m_obj_file->GetModule()->GetTypeList();
271 }
272 void SymbolFileDWARF::GetTypes(const DWARFDIE &die, dw_offset_t min_die_offset,
273                                dw_offset_t max_die_offset, uint32_t type_mask,
274                                TypeSet &type_set) {
275   if (die) {
276     const dw_offset_t die_offset = die.GetOffset();
277 
278     if (die_offset >= max_die_offset)
279       return;
280 
281     if (die_offset >= min_die_offset) {
282       const dw_tag_t tag = die.Tag();
283 
284       bool add_type = false;
285 
286       switch (tag) {
287       case DW_TAG_array_type:
288         add_type = (type_mask & eTypeClassArray) != 0;
289         break;
290       case DW_TAG_unspecified_type:
291       case DW_TAG_base_type:
292         add_type = (type_mask & eTypeClassBuiltin) != 0;
293         break;
294       case DW_TAG_class_type:
295         add_type = (type_mask & eTypeClassClass) != 0;
296         break;
297       case DW_TAG_structure_type:
298         add_type = (type_mask & eTypeClassStruct) != 0;
299         break;
300       case DW_TAG_union_type:
301         add_type = (type_mask & eTypeClassUnion) != 0;
302         break;
303       case DW_TAG_enumeration_type:
304         add_type = (type_mask & eTypeClassEnumeration) != 0;
305         break;
306       case DW_TAG_subroutine_type:
307       case DW_TAG_subprogram:
308       case DW_TAG_inlined_subroutine:
309         add_type = (type_mask & eTypeClassFunction) != 0;
310         break;
311       case DW_TAG_pointer_type:
312         add_type = (type_mask & eTypeClassPointer) != 0;
313         break;
314       case DW_TAG_rvalue_reference_type:
315       case DW_TAG_reference_type:
316         add_type = (type_mask & eTypeClassReference) != 0;
317         break;
318       case DW_TAG_typedef:
319         add_type = (type_mask & eTypeClassTypedef) != 0;
320         break;
321       case DW_TAG_ptr_to_member_type:
322         add_type = (type_mask & eTypeClassMemberPointer) != 0;
323         break;
324       }
325 
326       if (add_type) {
327         const bool assert_not_being_parsed = true;
328         Type *type = ResolveTypeUID(die, assert_not_being_parsed);
329         if (type) {
330           if (type_set.find(type) == type_set.end())
331             type_set.insert(type);
332         }
333       }
334     }
335 
336     for (DWARFDIE child_die = die.GetFirstChild(); child_die.IsValid();
337          child_die = child_die.GetSibling()) {
338       GetTypes(child_die, min_die_offset, max_die_offset, type_mask, type_set);
339     }
340   }
341 }
342 
343 size_t SymbolFileDWARF::GetTypes(SymbolContextScope *sc_scope,
344                                  uint32_t type_mask, TypeList &type_list)
345 
346 {
347   ASSERT_MODULE_LOCK(this);
348   TypeSet type_set;
349 
350   CompileUnit *comp_unit = NULL;
351   DWARFUnit *dwarf_cu = NULL;
352   if (sc_scope)
353     comp_unit = sc_scope->CalculateSymbolContextCompileUnit();
354 
355   if (comp_unit) {
356     dwarf_cu = GetDWARFCompileUnit(comp_unit);
357     if (dwarf_cu == 0)
358       return 0;
359     GetTypes(dwarf_cu->DIE(), dwarf_cu->GetOffset(),
360              dwarf_cu->GetNextCompileUnitOffset(), type_mask, type_set);
361   } else {
362     DWARFDebugInfo *info = DebugInfo();
363     if (info) {
364       const size_t num_cus = info->GetNumCompileUnits();
365       for (size_t cu_idx = 0; cu_idx < num_cus; ++cu_idx) {
366         dwarf_cu = info->GetCompileUnitAtIndex(cu_idx);
367         if (dwarf_cu) {
368           GetTypes(dwarf_cu->DIE(), 0, UINT32_MAX, type_mask, type_set);
369         }
370       }
371     }
372   }
373 
374   std::set<CompilerType> compiler_type_set;
375   size_t num_types_added = 0;
376   for (Type *type : type_set) {
377     CompilerType compiler_type = type->GetForwardCompilerType();
378     if (compiler_type_set.find(compiler_type) == compiler_type_set.end()) {
379       compiler_type_set.insert(compiler_type);
380       type_list.Insert(type->shared_from_this());
381       ++num_types_added;
382     }
383   }
384   return num_types_added;
385 }
386 
387 //----------------------------------------------------------------------
388 // Gets the first parent that is a lexical block, function or inlined
389 // subroutine, or compile unit.
390 //----------------------------------------------------------------------
391 DWARFDIE
392 SymbolFileDWARF::GetParentSymbolContextDIE(const DWARFDIE &child_die) {
393   DWARFDIE die;
394   for (die = child_die.GetParent(); die; die = die.GetParent()) {
395     dw_tag_t tag = die.Tag();
396 
397     switch (tag) {
398     case DW_TAG_compile_unit:
399     case DW_TAG_partial_unit:
400     case DW_TAG_subprogram:
401     case DW_TAG_inlined_subroutine:
402     case DW_TAG_lexical_block:
403       return die;
404     }
405   }
406   return DWARFDIE();
407 }
408 
409 SymbolFileDWARF::SymbolFileDWARF(ObjectFile *objfile)
410     : SymbolFile(objfile), UserID(uint64_t(DW_INVALID_OFFSET)
411                                   << 32), // Used by SymbolFileDWARFDebugMap to
412                                           // when this class parses .o files to
413                                           // contain the .o file index/ID
414       m_debug_map_module_wp(), m_debug_map_symfile(NULL), m_data_debug_abbrev(),
415       m_data_debug_aranges(), m_data_debug_frame(), m_data_debug_info(),
416       m_data_debug_line(), m_data_debug_macro(), m_data_debug_loc(),
417       m_data_debug_ranges(), m_data_debug_rnglists(), m_data_debug_str(),
418       m_data_apple_names(), m_data_apple_types(), m_data_apple_namespaces(),
419       m_abbr(), m_info(), m_line(), m_fetched_external_modules(false),
420       m_supports_DW_AT_APPLE_objc_complete_type(eLazyBoolCalculate), m_ranges(),
421       m_unique_ast_type_map() {}
422 
423 SymbolFileDWARF::~SymbolFileDWARF() {}
424 
425 static const ConstString &GetDWARFMachOSegmentName() {
426   static ConstString g_dwarf_section_name("__DWARF");
427   return g_dwarf_section_name;
428 }
429 
430 UniqueDWARFASTTypeMap &SymbolFileDWARF::GetUniqueDWARFASTTypeMap() {
431   SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
432   if (debug_map_symfile)
433     return debug_map_symfile->GetUniqueDWARFASTTypeMap();
434   else
435     return m_unique_ast_type_map;
436 }
437 
438 TypeSystem *SymbolFileDWARF::GetTypeSystemForLanguage(LanguageType language) {
439   SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
440   TypeSystem *type_system;
441   if (debug_map_symfile) {
442     type_system = debug_map_symfile->GetTypeSystemForLanguage(language);
443   } else {
444     type_system = m_obj_file->GetModule()->GetTypeSystemForLanguage(language);
445     if (type_system)
446       type_system->SetSymbolFile(this);
447   }
448   return type_system;
449 }
450 
451 void SymbolFileDWARF::InitializeObject() {
452   Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO);
453   ModuleSP module_sp(m_obj_file->GetModule());
454   if (module_sp) {
455     const SectionList *section_list = module_sp->GetSectionList();
456     Section *section =
457         section_list->FindSectionByName(GetDWARFMachOSegmentName()).get();
458 
459     if (section)
460       m_obj_file->ReadSectionData(section, m_dwarf_data);
461   }
462 
463   if (!GetGlobalPluginProperties()->IgnoreFileIndexes()) {
464     DWARFDataExtractor apple_names, apple_namespaces, apple_types, apple_objc;
465     LoadSectionData(eSectionTypeDWARFAppleNames, apple_names);
466     LoadSectionData(eSectionTypeDWARFAppleNamespaces, apple_namespaces);
467     LoadSectionData(eSectionTypeDWARFAppleTypes, apple_types);
468     LoadSectionData(eSectionTypeDWARFAppleObjC, apple_objc);
469 
470     m_index = AppleDWARFIndex::Create(
471         *GetObjectFile()->GetModule(), apple_names, apple_namespaces,
472         apple_types, apple_objc, get_debug_str_data());
473 
474     if (m_index)
475       return;
476 
477     DWARFDataExtractor debug_names;
478     LoadSectionData(eSectionTypeDWARFDebugNames, debug_names);
479     if (debug_names.GetByteSize() > 0) {
480       llvm::Expected<std::unique_ptr<DebugNamesDWARFIndex>> index_or =
481           DebugNamesDWARFIndex::Create(*GetObjectFile()->GetModule(),
482                                        debug_names, get_debug_str_data(),
483                                        DebugInfo());
484       if (index_or) {
485         m_index = std::move(*index_or);
486         return;
487       }
488       LLDB_LOG_ERROR(log, index_or.takeError(),
489                      "Unable to read .debug_names data: {0}");
490     }
491   }
492 
493   m_index = llvm::make_unique<ManualDWARFIndex>(*GetObjectFile()->GetModule(),
494                                                 DebugInfo());
495 }
496 
497 bool SymbolFileDWARF::SupportedVersion(uint16_t version) {
498   return version >= 2 && version <= 5;
499 }
500 
501 uint32_t SymbolFileDWARF::CalculateAbilities() {
502   uint32_t abilities = 0;
503   if (m_obj_file != NULL) {
504     const Section *section = NULL;
505     const SectionList *section_list = m_obj_file->GetSectionList();
506     if (section_list == NULL)
507       return 0;
508 
509     // On non Apple platforms we might have .debug_types debug info that is
510     // created by using "-fdebug-types-section". LLDB currently will try to
511     // load this debug info, but it causes crashes during debugging when types
512     // are missing since it doesn't know how to parse the info in the
513     // .debug_types type units. This causes all complex debug info types to be
514     // unresolved. Because this causes LLDB to crash and since it really
515     // doesn't provide a solid debuggiung experience, we should disable trying
516     // to debug this kind of DWARF until support gets added or deprecated.
517     if (section_list->FindSectionByName(ConstString(".debug_types"))) {
518       m_obj_file->GetModule()->ReportWarning(
519         "lldb doesn’t support .debug_types debug info");
520       return 0;
521     }
522 
523     uint64_t debug_abbrev_file_size = 0;
524     uint64_t debug_info_file_size = 0;
525     uint64_t debug_line_file_size = 0;
526 
527     section = section_list->FindSectionByName(GetDWARFMachOSegmentName()).get();
528 
529     if (section)
530       section_list = &section->GetChildren();
531 
532     section =
533         section_list->FindSectionByType(eSectionTypeDWARFDebugInfo, true).get();
534     if (section != NULL) {
535       debug_info_file_size = section->GetFileSize();
536 
537       section =
538           section_list->FindSectionByType(eSectionTypeDWARFDebugAbbrev, true)
539               .get();
540       if (section)
541         debug_abbrev_file_size = section->GetFileSize();
542 
543       DWARFDebugAbbrev *abbrev = DebugAbbrev();
544       if (abbrev) {
545         std::set<dw_form_t> invalid_forms;
546         abbrev->GetUnsupportedForms(invalid_forms);
547         if (!invalid_forms.empty()) {
548           StreamString error;
549           error.Printf("unsupported DW_FORM value%s:", invalid_forms.size() > 1 ? "s" : "");
550           for (auto form : invalid_forms)
551             error.Printf(" %#x", form);
552           m_obj_file->GetModule()->ReportWarning("%s", error.GetString().str().c_str());
553           return 0;
554         }
555       }
556 
557       section =
558           section_list->FindSectionByType(eSectionTypeDWARFDebugLine, true)
559               .get();
560       if (section)
561         debug_line_file_size = section->GetFileSize();
562     } else {
563       const char *symfile_dir_cstr =
564           m_obj_file->GetFileSpec().GetDirectory().GetCString();
565       if (symfile_dir_cstr) {
566         if (strcasestr(symfile_dir_cstr, ".dsym")) {
567           if (m_obj_file->GetType() == ObjectFile::eTypeDebugInfo) {
568             // We have a dSYM file that didn't have a any debug info. If the
569             // string table has a size of 1, then it was made from an
570             // executable with no debug info, or from an executable that was
571             // stripped.
572             section =
573                 section_list->FindSectionByType(eSectionTypeDWARFDebugStr, true)
574                     .get();
575             if (section && section->GetFileSize() == 1) {
576               m_obj_file->GetModule()->ReportWarning(
577                   "empty dSYM file detected, dSYM was created with an "
578                   "executable with no debug info.");
579             }
580           }
581         }
582       }
583     }
584 
585     if (debug_abbrev_file_size > 0 && debug_info_file_size > 0)
586       abilities |= CompileUnits | Functions | Blocks | GlobalVariables |
587                    LocalVariables | VariableTypes;
588 
589     if (debug_line_file_size > 0)
590       abilities |= LineTables;
591   }
592   return abilities;
593 }
594 
595 const DWARFDataExtractor &
596 SymbolFileDWARF::GetCachedSectionData(lldb::SectionType sect_type,
597                                       DWARFDataSegment &data_segment) {
598   llvm::call_once(data_segment.m_flag, [this, sect_type, &data_segment] {
599     this->LoadSectionData(sect_type, std::ref(data_segment.m_data));
600   });
601   return data_segment.m_data;
602 }
603 
604 void SymbolFileDWARF::LoadSectionData(lldb::SectionType sect_type,
605                                       DWARFDataExtractor &data) {
606   ModuleSP module_sp(m_obj_file->GetModule());
607   const SectionList *section_list = module_sp->GetSectionList();
608   if (section_list) {
609     SectionSP section_sp(section_list->FindSectionByType(sect_type, true));
610     if (section_sp) {
611       // See if we memory mapped the DWARF segment?
612       if (m_dwarf_data.GetByteSize()) {
613         data.SetData(m_dwarf_data, section_sp->GetOffset(),
614                      section_sp->GetFileSize());
615       } else {
616         if (m_obj_file->ReadSectionData(section_sp.get(), data) == 0)
617           data.Clear();
618       }
619     }
620   }
621 }
622 
623 const DWARFDataExtractor &SymbolFileDWARF::get_debug_abbrev_data() {
624   return GetCachedSectionData(eSectionTypeDWARFDebugAbbrev,
625                               m_data_debug_abbrev);
626 }
627 
628 const DWARFDataExtractor &SymbolFileDWARF::get_debug_addr_data() {
629   return GetCachedSectionData(eSectionTypeDWARFDebugAddr, m_data_debug_addr);
630 }
631 
632 const DWARFDataExtractor &SymbolFileDWARF::get_debug_aranges_data() {
633   return GetCachedSectionData(eSectionTypeDWARFDebugAranges,
634                               m_data_debug_aranges);
635 }
636 
637 const DWARFDataExtractor &SymbolFileDWARF::get_debug_frame_data() {
638   return GetCachedSectionData(eSectionTypeDWARFDebugFrame, m_data_debug_frame);
639 }
640 
641 const DWARFDataExtractor &SymbolFileDWARF::get_debug_info_data() {
642   return GetCachedSectionData(eSectionTypeDWARFDebugInfo, m_data_debug_info);
643 }
644 
645 const DWARFDataExtractor &SymbolFileDWARF::get_debug_line_data() {
646   return GetCachedSectionData(eSectionTypeDWARFDebugLine, m_data_debug_line);
647 }
648 
649 const DWARFDataExtractor &SymbolFileDWARF::get_debug_line_str_data() {
650  return GetCachedSectionData(eSectionTypeDWARFDebugLineStr, m_data_debug_line_str);
651 }
652 
653 const DWARFDataExtractor &SymbolFileDWARF::get_debug_macro_data() {
654   return GetCachedSectionData(eSectionTypeDWARFDebugMacro, m_data_debug_macro);
655 }
656 
657 const DWARFDataExtractor &SymbolFileDWARF::get_debug_loc_data() {
658   return GetCachedSectionData(eSectionTypeDWARFDebugLoc, m_data_debug_loc);
659 }
660 
661 const DWARFDataExtractor &SymbolFileDWARF::get_debug_ranges_data() {
662   return GetCachedSectionData(eSectionTypeDWARFDebugRanges,
663                               m_data_debug_ranges);
664 }
665 
666 const DWARFDataExtractor &SymbolFileDWARF::get_debug_rnglists_data() {
667   return GetCachedSectionData(eSectionTypeDWARFDebugRngLists,
668                               m_data_debug_rnglists);
669 }
670 
671 const DWARFDataExtractor &SymbolFileDWARF::get_debug_str_data() {
672   return GetCachedSectionData(eSectionTypeDWARFDebugStr, m_data_debug_str);
673 }
674 
675 const DWARFDataExtractor &SymbolFileDWARF::get_debug_str_offsets_data() {
676   return GetCachedSectionData(eSectionTypeDWARFDebugStrOffsets,
677                               m_data_debug_str_offsets);
678 }
679 
680 const DWARFDataExtractor &SymbolFileDWARF::get_debug_types_data() {
681   return GetCachedSectionData(eSectionTypeDWARFDebugTypes, m_data_debug_types);
682 }
683 
684 const DWARFDataExtractor &SymbolFileDWARF::get_apple_names_data() {
685   return GetCachedSectionData(eSectionTypeDWARFAppleNames, m_data_apple_names);
686 }
687 
688 const DWARFDataExtractor &SymbolFileDWARF::get_apple_types_data() {
689   return GetCachedSectionData(eSectionTypeDWARFAppleTypes, m_data_apple_types);
690 }
691 
692 const DWARFDataExtractor &SymbolFileDWARF::get_apple_namespaces_data() {
693   return GetCachedSectionData(eSectionTypeDWARFAppleNamespaces,
694                               m_data_apple_namespaces);
695 }
696 
697 const DWARFDataExtractor &SymbolFileDWARF::get_apple_objc_data() {
698   return GetCachedSectionData(eSectionTypeDWARFAppleObjC, m_data_apple_objc);
699 }
700 
701 const DWARFDataExtractor &SymbolFileDWARF::get_gnu_debugaltlink() {
702   return GetCachedSectionData(eSectionTypeDWARFGNUDebugAltLink,
703                               m_data_gnu_debugaltlink);
704 }
705 
706 DWARFDebugAbbrev *SymbolFileDWARF::DebugAbbrev() {
707   if (m_abbr.get() == NULL) {
708     const DWARFDataExtractor &debug_abbrev_data = get_debug_abbrev_data();
709     if (debug_abbrev_data.GetByteSize() > 0) {
710       m_abbr.reset(new DWARFDebugAbbrev());
711       if (m_abbr.get())
712         m_abbr->Parse(debug_abbrev_data);
713     }
714   }
715   return m_abbr.get();
716 }
717 
718 const DWARFDebugAbbrev *SymbolFileDWARF::DebugAbbrev() const {
719   return m_abbr.get();
720 }
721 
722 DWARFDebugInfo *SymbolFileDWARF::DebugInfo() {
723   if (m_info.get() == NULL) {
724     static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
725     Timer scoped_timer(func_cat, "%s this = %p", LLVM_PRETTY_FUNCTION,
726                        static_cast<void *>(this));
727     if (get_debug_info_data().GetByteSize() > 0) {
728       m_info.reset(new DWARFDebugInfo());
729       if (m_info.get()) {
730         m_info->SetDwarfData(this);
731       }
732     }
733   }
734   return m_info.get();
735 }
736 
737 const DWARFDebugInfo *SymbolFileDWARF::DebugInfo() const {
738   return m_info.get();
739 }
740 
741 DWARFUnit *
742 SymbolFileDWARF::GetDWARFCompileUnit(lldb_private::CompileUnit *comp_unit) {
743   if (!comp_unit)
744     return nullptr;
745 
746   DWARFDebugInfo *info = DebugInfo();
747   if (info) {
748     // Just a normal DWARF file whose user ID for the compile unit is the DWARF
749     // offset itself
750 
751     DWARFUnit *dwarf_cu =
752         info->GetCompileUnit((dw_offset_t)comp_unit->GetID());
753     if (dwarf_cu && dwarf_cu->GetUserData() == NULL)
754       dwarf_cu->SetUserData(comp_unit);
755     return dwarf_cu;
756   }
757   return NULL;
758 }
759 
760 DWARFDebugRanges *SymbolFileDWARF::DebugRanges() {
761   if (m_ranges.get() == NULL) {
762     static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
763     Timer scoped_timer(func_cat, "%s this = %p", LLVM_PRETTY_FUNCTION,
764                        static_cast<void *>(this));
765 
766     if (get_debug_ranges_data().GetByteSize() > 0)
767       m_ranges.reset(new DWARFDebugRanges());
768     else if (get_debug_rnglists_data().GetByteSize() > 0)
769       m_ranges.reset(new DWARFDebugRngLists());
770 
771     if (m_ranges.get())
772       m_ranges->Extract(this);
773   }
774   return m_ranges.get();
775 }
776 
777 const DWARFDebugRanges *SymbolFileDWARF::DebugRanges() const {
778   return m_ranges.get();
779 }
780 
781 lldb::CompUnitSP SymbolFileDWARF::ParseCompileUnit(DWARFUnit *dwarf_cu,
782                                                    uint32_t cu_idx) {
783   CompUnitSP cu_sp;
784   if (dwarf_cu) {
785     CompileUnit *comp_unit = (CompileUnit *)dwarf_cu->GetUserData();
786     if (comp_unit) {
787       // We already parsed this compile unit, had out a shared pointer to it
788       cu_sp = comp_unit->shared_from_this();
789     } else {
790       if (dwarf_cu->GetSymbolFileDWARF() != this) {
791         return dwarf_cu->GetSymbolFileDWARF()->ParseCompileUnit(dwarf_cu,
792                                                                 cu_idx);
793       } else if (dwarf_cu->GetOffset() == 0 && GetDebugMapSymfile()) {
794         // Let the debug map create the compile unit
795         cu_sp = m_debug_map_symfile->GetCompileUnit(this);
796         dwarf_cu->SetUserData(cu_sp.get());
797       } else {
798         ModuleSP module_sp(m_obj_file->GetModule());
799         if (module_sp) {
800           const DWARFDIE cu_die = dwarf_cu->DIE();
801           if (cu_die) {
802             FileSpec cu_file_spec{cu_die.GetName(), false};
803             if (cu_file_spec) {
804               // If we have a full path to the compile unit, we don't need to
805               // resolve the file.  This can be expensive e.g. when the source
806               // files are
807               // NFS mounted.
808               if (cu_file_spec.IsRelative()) {
809                 const char *cu_comp_dir{
810                     cu_die.GetAttributeValueAsString(DW_AT_comp_dir, nullptr)};
811                 cu_file_spec.PrependPathComponent(resolveCompDir(cu_comp_dir));
812               }
813 
814               std::string remapped_file;
815               if (module_sp->RemapSourceFile(cu_file_spec.GetPath(),
816                                              remapped_file))
817                 cu_file_spec.SetFile(remapped_file, false,
818                                      FileSpec::Style::native);
819             }
820 
821             LanguageType cu_language = DWARFUnit::LanguageTypeFromDWARF(
822                 cu_die.GetAttributeValueAsUnsigned(DW_AT_language, 0));
823 
824             bool is_optimized = dwarf_cu->GetIsOptimized();
825             cu_sp.reset(new CompileUnit(
826                 module_sp, dwarf_cu, cu_file_spec, dwarf_cu->GetID(),
827                 cu_language, is_optimized ? eLazyBoolYes : eLazyBoolNo));
828             if (cu_sp) {
829               // If we just created a compile unit with an invalid file spec,
830               // try and get the first entry in the supports files from the
831               // line table as that should be the compile unit.
832               if (!cu_file_spec) {
833                 cu_file_spec = cu_sp->GetSupportFiles().GetFileSpecAtIndex(1);
834                 if (cu_file_spec) {
835                   (FileSpec &)(*cu_sp) = cu_file_spec;
836                   // Also fix the invalid file spec which was copied from the
837                   // compile unit.
838                   cu_sp->GetSupportFiles().Replace(0, cu_file_spec);
839                 }
840               }
841 
842               dwarf_cu->SetUserData(cu_sp.get());
843 
844               // Figure out the compile unit index if we weren't given one
845               if (cu_idx == UINT32_MAX)
846                 DebugInfo()->GetCompileUnit(dwarf_cu->GetOffset(), &cu_idx);
847 
848               m_obj_file->GetModule()->GetSymbolVendor()->SetCompileUnitAtIndex(
849                   cu_idx, cu_sp);
850             }
851           }
852         }
853       }
854     }
855   }
856   return cu_sp;
857 }
858 
859 uint32_t SymbolFileDWARF::GetNumCompileUnits() {
860   DWARFDebugInfo *info = DebugInfo();
861   if (info)
862     return info->GetNumCompileUnits();
863   return 0;
864 }
865 
866 CompUnitSP SymbolFileDWARF::ParseCompileUnitAtIndex(uint32_t cu_idx) {
867   ASSERT_MODULE_LOCK(this);
868   CompUnitSP cu_sp;
869   DWARFDebugInfo *info = DebugInfo();
870   if (info) {
871     DWARFUnit *dwarf_cu = info->GetCompileUnitAtIndex(cu_idx);
872     if (dwarf_cu)
873       cu_sp = ParseCompileUnit(dwarf_cu, cu_idx);
874   }
875   return cu_sp;
876 }
877 
878 Function *SymbolFileDWARF::ParseCompileUnitFunction(const SymbolContext &sc,
879                                                     const DWARFDIE &die) {
880   ASSERT_MODULE_LOCK(this);
881   if (die.IsValid()) {
882     TypeSystem *type_system =
883         GetTypeSystemForLanguage(die.GetCU()->GetLanguageType());
884 
885     if (type_system) {
886       DWARFASTParser *dwarf_ast = type_system->GetDWARFParser();
887       if (dwarf_ast)
888         return dwarf_ast->ParseFunctionFromDWARF(sc, die);
889     }
890   }
891   return nullptr;
892 }
893 
894 bool SymbolFileDWARF::FixupAddress(Address &addr) {
895   SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
896   if (debug_map_symfile) {
897     return debug_map_symfile->LinkOSOAddress(addr);
898   }
899   // This is a normal DWARF file, no address fixups need to happen
900   return true;
901 }
902 lldb::LanguageType
903 SymbolFileDWARF::ParseCompileUnitLanguage(const SymbolContext &sc) {
904   ASSERT_MODULE_LOCK(this);
905   assert(sc.comp_unit);
906   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
907   if (dwarf_cu)
908     return dwarf_cu->GetLanguageType();
909   else
910     return eLanguageTypeUnknown;
911 }
912 
913 size_t SymbolFileDWARF::ParseCompileUnitFunctions(const SymbolContext &sc) {
914   ASSERT_MODULE_LOCK(this);
915   assert(sc.comp_unit);
916   size_t functions_added = 0;
917   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
918   if (dwarf_cu) {
919     DWARFDIECollection function_dies;
920     const size_t num_functions =
921         dwarf_cu->AppendDIEsWithTag(DW_TAG_subprogram, function_dies);
922     size_t func_idx;
923     for (func_idx = 0; func_idx < num_functions; ++func_idx) {
924       DWARFDIE die = function_dies.GetDIEAtIndex(func_idx);
925       if (sc.comp_unit->FindFunctionByUID(die.GetID()).get() == NULL) {
926         if (ParseCompileUnitFunction(sc, die))
927           ++functions_added;
928       }
929     }
930     // FixupTypes();
931   }
932   return functions_added;
933 }
934 
935 bool SymbolFileDWARF::ParseCompileUnitSupportFiles(
936     const SymbolContext &sc, FileSpecList &support_files) {
937   ASSERT_MODULE_LOCK(this);
938   assert(sc.comp_unit);
939   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
940   if (dwarf_cu) {
941     const DWARFBaseDIE cu_die = dwarf_cu->GetUnitDIEOnly();
942 
943     if (cu_die) {
944       FileSpec cu_comp_dir = resolveCompDir(
945           cu_die.GetAttributeValueAsString(DW_AT_comp_dir, nullptr));
946       const dw_offset_t stmt_list = cu_die.GetAttributeValueAsUnsigned(
947           DW_AT_stmt_list, DW_INVALID_OFFSET);
948       if (stmt_list != DW_INVALID_OFFSET) {
949         // All file indexes in DWARF are one based and a file of index zero is
950         // supposed to be the compile unit itself.
951         support_files.Append(*sc.comp_unit);
952         return DWARFDebugLine::ParseSupportFiles(
953             sc.comp_unit->GetModule(), get_debug_line_data(), cu_comp_dir,
954             stmt_list, support_files, dwarf_cu);
955       }
956     }
957   }
958   return false;
959 }
960 
961 bool SymbolFileDWARF::ParseCompileUnitIsOptimized(
962     const lldb_private::SymbolContext &sc) {
963   ASSERT_MODULE_LOCK(this);
964   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
965   if (dwarf_cu)
966     return dwarf_cu->GetIsOptimized();
967   return false;
968 }
969 
970 bool SymbolFileDWARF::ParseImportedModules(
971     const lldb_private::SymbolContext &sc,
972     std::vector<lldb_private::ConstString> &imported_modules) {
973   ASSERT_MODULE_LOCK(this);
974   assert(sc.comp_unit);
975   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
976   if (dwarf_cu) {
977     if (ClangModulesDeclVendor::LanguageSupportsClangModules(
978             sc.comp_unit->GetLanguage())) {
979       UpdateExternalModuleListIfNeeded();
980 
981       if (sc.comp_unit) {
982         const DWARFDIE die = dwarf_cu->DIE();
983 
984         if (die) {
985           for (DWARFDIE child_die = die.GetFirstChild(); child_die;
986                child_die = child_die.GetSibling()) {
987             if (child_die.Tag() == DW_TAG_imported_declaration) {
988               if (DWARFDIE module_die =
989                       child_die.GetReferencedDIE(DW_AT_import)) {
990                 if (module_die.Tag() == DW_TAG_module) {
991                   if (const char *name = module_die.GetAttributeValueAsString(
992                           DW_AT_name, nullptr)) {
993                     ConstString const_name(name);
994                     imported_modules.push_back(const_name);
995                   }
996                 }
997               }
998             }
999           }
1000         }
1001       } else {
1002         for (const auto &pair : m_external_type_modules) {
1003           imported_modules.push_back(pair.first);
1004         }
1005       }
1006     }
1007   }
1008   return false;
1009 }
1010 
1011 struct ParseDWARFLineTableCallbackInfo {
1012   LineTable *line_table;
1013   std::unique_ptr<LineSequence> sequence_ap;
1014   lldb::addr_t addr_mask;
1015 };
1016 
1017 //----------------------------------------------------------------------
1018 // ParseStatementTableCallback
1019 //----------------------------------------------------------------------
1020 static void ParseDWARFLineTableCallback(dw_offset_t offset,
1021                                         const DWARFDebugLine::State &state,
1022                                         void *userData) {
1023   if (state.row == DWARFDebugLine::State::StartParsingLineTable) {
1024     // Just started parsing the line table
1025   } else if (state.row == DWARFDebugLine::State::DoneParsingLineTable) {
1026     // Done parsing line table, nothing to do for the cleanup
1027   } else {
1028     ParseDWARFLineTableCallbackInfo *info =
1029         (ParseDWARFLineTableCallbackInfo *)userData;
1030     LineTable *line_table = info->line_table;
1031 
1032     // If this is our first time here, we need to create a sequence container.
1033     if (!info->sequence_ap.get()) {
1034       info->sequence_ap.reset(line_table->CreateLineSequenceContainer());
1035       assert(info->sequence_ap.get());
1036     }
1037     line_table->AppendLineEntryToSequence(
1038         info->sequence_ap.get(), state.address & info->addr_mask, state.line,
1039         state.column, state.file, state.is_stmt, state.basic_block,
1040         state.prologue_end, state.epilogue_begin, state.end_sequence);
1041     if (state.end_sequence) {
1042       // First, put the current sequence into the line table.
1043       line_table->InsertSequence(info->sequence_ap.get());
1044       // Then, empty it to prepare for the next sequence.
1045       info->sequence_ap->Clear();
1046     }
1047   }
1048 }
1049 
1050 bool SymbolFileDWARF::ParseCompileUnitLineTable(const SymbolContext &sc) {
1051   ASSERT_MODULE_LOCK(this);
1052   assert(sc.comp_unit);
1053   if (sc.comp_unit->GetLineTable() != NULL)
1054     return true;
1055 
1056   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
1057   if (dwarf_cu) {
1058     const DWARFBaseDIE dwarf_cu_die = dwarf_cu->GetUnitDIEOnly();
1059     if (dwarf_cu_die) {
1060       const dw_offset_t cu_line_offset =
1061           dwarf_cu_die.GetAttributeValueAsUnsigned(DW_AT_stmt_list,
1062                                                    DW_INVALID_OFFSET);
1063       if (cu_line_offset != DW_INVALID_OFFSET) {
1064         std::unique_ptr<LineTable> line_table_ap(new LineTable(sc.comp_unit));
1065         if (line_table_ap.get()) {
1066           ParseDWARFLineTableCallbackInfo info;
1067           info.line_table = line_table_ap.get();
1068 
1069           /*
1070            * MIPS:
1071            * The SymbolContext may not have a valid target, thus we may not be
1072            * able
1073            * to call Address::GetOpcodeLoadAddress() which would clear the bit
1074            * #0
1075            * for MIPS. Use ArchSpec to clear the bit #0.
1076           */
1077           ArchSpec arch;
1078           GetObjectFile()->GetArchitecture(arch);
1079           switch (arch.GetMachine()) {
1080           case llvm::Triple::mips:
1081           case llvm::Triple::mipsel:
1082           case llvm::Triple::mips64:
1083           case llvm::Triple::mips64el:
1084             info.addr_mask = ~((lldb::addr_t)1);
1085             break;
1086           default:
1087             info.addr_mask = ~((lldb::addr_t)0);
1088             break;
1089           }
1090 
1091           lldb::offset_t offset = cu_line_offset;
1092           DWARFDebugLine::ParseStatementTable(get_debug_line_data(), &offset,
1093                                               ParseDWARFLineTableCallback,
1094                                               &info, dwarf_cu);
1095           SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
1096           if (debug_map_symfile) {
1097             // We have an object file that has a line table with addresses that
1098             // are not linked. We need to link the line table and convert the
1099             // addresses that are relative to the .o file into addresses for
1100             // the main executable.
1101             sc.comp_unit->SetLineTable(
1102                 debug_map_symfile->LinkOSOLineTable(this, line_table_ap.get()));
1103           } else {
1104             sc.comp_unit->SetLineTable(line_table_ap.release());
1105             return true;
1106           }
1107         }
1108       }
1109     }
1110   }
1111   return false;
1112 }
1113 
1114 lldb_private::DebugMacrosSP
1115 SymbolFileDWARF::ParseDebugMacros(lldb::offset_t *offset) {
1116   auto iter = m_debug_macros_map.find(*offset);
1117   if (iter != m_debug_macros_map.end())
1118     return iter->second;
1119 
1120   const DWARFDataExtractor &debug_macro_data = get_debug_macro_data();
1121   if (debug_macro_data.GetByteSize() == 0)
1122     return DebugMacrosSP();
1123 
1124   lldb_private::DebugMacrosSP debug_macros_sp(new lldb_private::DebugMacros());
1125   m_debug_macros_map[*offset] = debug_macros_sp;
1126 
1127   const DWARFDebugMacroHeader &header =
1128       DWARFDebugMacroHeader::ParseHeader(debug_macro_data, offset);
1129   DWARFDebugMacroEntry::ReadMacroEntries(debug_macro_data, get_debug_str_data(),
1130                                          header.OffsetIs64Bit(), offset, this,
1131                                          debug_macros_sp);
1132 
1133   return debug_macros_sp;
1134 }
1135 
1136 bool SymbolFileDWARF::ParseCompileUnitDebugMacros(const SymbolContext &sc) {
1137   ASSERT_MODULE_LOCK(this);
1138   assert(sc.comp_unit);
1139 
1140   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
1141   if (dwarf_cu == nullptr)
1142     return false;
1143 
1144   const DWARFBaseDIE dwarf_cu_die = dwarf_cu->GetUnitDIEOnly();
1145   if (!dwarf_cu_die)
1146     return false;
1147 
1148   lldb::offset_t sect_offset =
1149       dwarf_cu_die.GetAttributeValueAsUnsigned(DW_AT_macros, DW_INVALID_OFFSET);
1150   if (sect_offset == DW_INVALID_OFFSET)
1151     sect_offset = dwarf_cu_die.GetAttributeValueAsUnsigned(DW_AT_GNU_macros,
1152                                                            DW_INVALID_OFFSET);
1153   if (sect_offset == DW_INVALID_OFFSET)
1154     return false;
1155 
1156   sc.comp_unit->SetDebugMacros(ParseDebugMacros(&sect_offset));
1157 
1158   return true;
1159 }
1160 
1161 size_t SymbolFileDWARF::ParseFunctionBlocks(const SymbolContext &sc,
1162                                             Block *parent_block,
1163                                             const DWARFDIE &orig_die,
1164                                             addr_t subprogram_low_pc,
1165                                             uint32_t depth) {
1166   size_t blocks_added = 0;
1167   DWARFDIE die = orig_die;
1168   while (die) {
1169     dw_tag_t tag = die.Tag();
1170 
1171     switch (tag) {
1172     case DW_TAG_inlined_subroutine:
1173     case DW_TAG_subprogram:
1174     case DW_TAG_lexical_block: {
1175       Block *block = NULL;
1176       if (tag == DW_TAG_subprogram) {
1177         // Skip any DW_TAG_subprogram DIEs that are inside of a normal or
1178         // inlined functions. These will be parsed on their own as separate
1179         // entities.
1180 
1181         if (depth > 0)
1182           break;
1183 
1184         block = parent_block;
1185       } else {
1186         BlockSP block_sp(new Block(die.GetID()));
1187         parent_block->AddChild(block_sp);
1188         block = block_sp.get();
1189       }
1190       DWARFRangeList ranges;
1191       const char *name = NULL;
1192       const char *mangled_name = NULL;
1193 
1194       int decl_file = 0;
1195       int decl_line = 0;
1196       int decl_column = 0;
1197       int call_file = 0;
1198       int call_line = 0;
1199       int call_column = 0;
1200       if (die.GetDIENamesAndRanges(name, mangled_name, ranges, decl_file,
1201                                    decl_line, decl_column, call_file, call_line,
1202                                    call_column, nullptr)) {
1203         if (tag == DW_TAG_subprogram) {
1204           assert(subprogram_low_pc == LLDB_INVALID_ADDRESS);
1205           subprogram_low_pc = ranges.GetMinRangeBase(0);
1206         } else if (tag == DW_TAG_inlined_subroutine) {
1207           // We get called here for inlined subroutines in two ways. The first
1208           // time is when we are making the Function object for this inlined
1209           // concrete instance.  Since we're creating a top level block at
1210           // here, the subprogram_low_pc will be LLDB_INVALID_ADDRESS.  So we
1211           // need to adjust the containing address. The second time is when we
1212           // are parsing the blocks inside the function that contains the
1213           // inlined concrete instance.  Since these will be blocks inside the
1214           // containing "real" function the offset will be for that function.
1215           if (subprogram_low_pc == LLDB_INVALID_ADDRESS) {
1216             subprogram_low_pc = ranges.GetMinRangeBase(0);
1217           }
1218         }
1219 
1220         const size_t num_ranges = ranges.GetSize();
1221         for (size_t i = 0; i < num_ranges; ++i) {
1222           const DWARFRangeList::Entry &range = ranges.GetEntryRef(i);
1223           const addr_t range_base = range.GetRangeBase();
1224           if (range_base >= subprogram_low_pc)
1225             block->AddRange(Block::Range(range_base - subprogram_low_pc,
1226                                          range.GetByteSize()));
1227           else {
1228             GetObjectFile()->GetModule()->ReportError(
1229                 "0x%8.8" PRIx64 ": adding range [0x%" PRIx64 "-0x%" PRIx64
1230                 ") which has a base that is less than the function's low PC "
1231                 "0x%" PRIx64 ". Please file a bug and attach the file at the "
1232                              "start of this error message",
1233                 block->GetID(), range_base, range.GetRangeEnd(),
1234                 subprogram_low_pc);
1235           }
1236         }
1237         block->FinalizeRanges();
1238 
1239         if (tag != DW_TAG_subprogram &&
1240             (name != NULL || mangled_name != NULL)) {
1241           std::unique_ptr<Declaration> decl_ap;
1242           if (decl_file != 0 || decl_line != 0 || decl_column != 0)
1243             decl_ap.reset(new Declaration(
1244                 sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(decl_file),
1245                 decl_line, decl_column));
1246 
1247           std::unique_ptr<Declaration> call_ap;
1248           if (call_file != 0 || call_line != 0 || call_column != 0)
1249             call_ap.reset(new Declaration(
1250                 sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(call_file),
1251                 call_line, call_column));
1252 
1253           block->SetInlinedFunctionInfo(name, mangled_name, decl_ap.get(),
1254                                         call_ap.get());
1255         }
1256 
1257         ++blocks_added;
1258 
1259         if (die.HasChildren()) {
1260           blocks_added += ParseFunctionBlocks(sc, block, die.GetFirstChild(),
1261                                               subprogram_low_pc, depth + 1);
1262         }
1263       }
1264     } break;
1265     default:
1266       break;
1267     }
1268 
1269     // Only parse siblings of the block if we are not at depth zero. A depth of
1270     // zero indicates we are currently parsing the top level DW_TAG_subprogram
1271     // DIE
1272 
1273     if (depth == 0)
1274       die.Clear();
1275     else
1276       die = die.GetSibling();
1277   }
1278   return blocks_added;
1279 }
1280 
1281 bool SymbolFileDWARF::ClassOrStructIsVirtual(const DWARFDIE &parent_die) {
1282   if (parent_die) {
1283     for (DWARFDIE die = parent_die.GetFirstChild(); die;
1284          die = die.GetSibling()) {
1285       dw_tag_t tag = die.Tag();
1286       bool check_virtuality = false;
1287       switch (tag) {
1288       case DW_TAG_inheritance:
1289       case DW_TAG_subprogram:
1290         check_virtuality = true;
1291         break;
1292       default:
1293         break;
1294       }
1295       if (check_virtuality) {
1296         if (die.GetAttributeValueAsUnsigned(DW_AT_virtuality, 0) != 0)
1297           return true;
1298       }
1299     }
1300   }
1301   return false;
1302 }
1303 
1304 void SymbolFileDWARF::ParseDeclsForContext(CompilerDeclContext decl_ctx) {
1305   TypeSystem *type_system = decl_ctx.GetTypeSystem();
1306   DWARFASTParser *ast_parser = type_system->GetDWARFParser();
1307   std::vector<DWARFDIE> decl_ctx_die_list =
1308       ast_parser->GetDIEForDeclContext(decl_ctx);
1309 
1310   for (DWARFDIE decl_ctx_die : decl_ctx_die_list)
1311     for (DWARFDIE decl = decl_ctx_die.GetFirstChild(); decl;
1312          decl = decl.GetSibling())
1313       ast_parser->GetDeclForUIDFromDWARF(decl);
1314 }
1315 
1316 SymbolFileDWARF *SymbolFileDWARF::GetDWARFForUID(lldb::user_id_t uid) {
1317   // This method can be called without going through the symbol vendor so we
1318   // need to lock the module.
1319   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1320   // Anytime we get a "lldb::user_id_t" from an lldb_private::SymbolFile API we
1321   // must make sure we use the correct DWARF file when resolving things. On
1322   // MacOSX, when using SymbolFileDWARFDebugMap, we will use multiple
1323   // SymbolFileDWARF classes, one for each .o file. We can often end up with
1324   // references to other DWARF objects and we must be ready to receive a
1325   // "lldb::user_id_t" that specifies a DIE from another SymbolFileDWARF
1326   // instance.
1327   SymbolFileDWARFDebugMap *debug_map = GetDebugMapSymfile();
1328   if (debug_map)
1329     return debug_map->GetSymbolFileByOSOIndex(
1330         debug_map->GetOSOIndexFromUserID(uid));
1331   return this;
1332 }
1333 
1334 DWARFDIE
1335 SymbolFileDWARF::GetDIEFromUID(lldb::user_id_t uid) {
1336   // This method can be called without going through the symbol vendor so we
1337   // need to lock the module.
1338   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1339   // Anytime we get a "lldb::user_id_t" from an lldb_private::SymbolFile API we
1340   // must make sure we use the correct DWARF file when resolving things. On
1341   // MacOSX, when using SymbolFileDWARFDebugMap, we will use multiple
1342   // SymbolFileDWARF classes, one for each .o file. We can often end up with
1343   // references to other DWARF objects and we must be ready to receive a
1344   // "lldb::user_id_t" that specifies a DIE from another SymbolFileDWARF
1345   // instance.
1346   SymbolFileDWARF *dwarf = GetDWARFForUID(uid);
1347   if (dwarf)
1348     return dwarf->GetDIE(DIERef(uid, dwarf));
1349   return DWARFDIE();
1350 }
1351 
1352 CompilerDecl SymbolFileDWARF::GetDeclForUID(lldb::user_id_t type_uid) {
1353   // This method can be called without going through the symbol vendor so we
1354   // need to lock the module.
1355   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1356   // Anytime we have a lldb::user_id_t, we must get the DIE by calling
1357   // SymbolFileDWARF::GetDIEFromUID(). See comments inside the
1358   // SymbolFileDWARF::GetDIEFromUID() for details.
1359   DWARFDIE die = GetDIEFromUID(type_uid);
1360   if (die)
1361     return die.GetDecl();
1362   return CompilerDecl();
1363 }
1364 
1365 CompilerDeclContext
1366 SymbolFileDWARF::GetDeclContextForUID(lldb::user_id_t type_uid) {
1367   // This method can be called without going through the symbol vendor so we
1368   // need to lock the module.
1369   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1370   // Anytime we have a lldb::user_id_t, we must get the DIE by calling
1371   // SymbolFileDWARF::GetDIEFromUID(). See comments inside the
1372   // SymbolFileDWARF::GetDIEFromUID() for details.
1373   DWARFDIE die = GetDIEFromUID(type_uid);
1374   if (die)
1375     return die.GetDeclContext();
1376   return CompilerDeclContext();
1377 }
1378 
1379 CompilerDeclContext
1380 SymbolFileDWARF::GetDeclContextContainingUID(lldb::user_id_t type_uid) {
1381   // This method can be called without going through the symbol vendor so we
1382   // need to lock the module.
1383   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1384   // Anytime we have a lldb::user_id_t, we must get the DIE by calling
1385   // SymbolFileDWARF::GetDIEFromUID(). See comments inside the
1386   // SymbolFileDWARF::GetDIEFromUID() for details.
1387   DWARFDIE die = GetDIEFromUID(type_uid);
1388   if (die)
1389     return die.GetContainingDeclContext();
1390   return CompilerDeclContext();
1391 }
1392 
1393 Type *SymbolFileDWARF::ResolveTypeUID(lldb::user_id_t type_uid) {
1394   // This method can be called without going through the symbol vendor so we
1395   // need to lock the module.
1396   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1397   // Anytime we have a lldb::user_id_t, we must get the DIE by calling
1398   // SymbolFileDWARF::GetDIEFromUID(). See comments inside the
1399   // SymbolFileDWARF::GetDIEFromUID() for details.
1400   DWARFDIE type_die = GetDIEFromUID(type_uid);
1401   if (type_die)
1402     return type_die.ResolveType();
1403   else
1404     return nullptr;
1405 }
1406 
1407 Type *SymbolFileDWARF::ResolveTypeUID(const DIERef &die_ref) {
1408   return ResolveType(GetDIE(die_ref), true);
1409 }
1410 
1411 Type *SymbolFileDWARF::ResolveTypeUID(const DWARFDIE &die,
1412                                       bool assert_not_being_parsed) {
1413   if (die) {
1414     Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO));
1415     if (log)
1416       GetObjectFile()->GetModule()->LogMessage(
1417           log, "SymbolFileDWARF::ResolveTypeUID (die = 0x%8.8x) %s '%s'",
1418           die.GetOffset(), die.GetTagAsCString(), die.GetName());
1419 
1420     // We might be coming in in the middle of a type tree (a class within a
1421     // class, an enum within a class), so parse any needed parent DIEs before
1422     // we get to this one...
1423     DWARFDIE decl_ctx_die = GetDeclContextDIEContainingDIE(die);
1424     if (decl_ctx_die) {
1425       if (log) {
1426         switch (decl_ctx_die.Tag()) {
1427         case DW_TAG_structure_type:
1428         case DW_TAG_union_type:
1429         case DW_TAG_class_type: {
1430           // Get the type, which could be a forward declaration
1431           if (log)
1432             GetObjectFile()->GetModule()->LogMessage(
1433                 log, "SymbolFileDWARF::ResolveTypeUID (die = 0x%8.8x) %s '%s' "
1434                      "resolve parent forward type for 0x%8.8x",
1435                 die.GetOffset(), die.GetTagAsCString(), die.GetName(),
1436                 decl_ctx_die.GetOffset());
1437         } break;
1438 
1439         default:
1440           break;
1441         }
1442       }
1443     }
1444     return ResolveType(die);
1445   }
1446   return NULL;
1447 }
1448 
1449 // This function is used when SymbolFileDWARFDebugMap owns a bunch of
1450 // SymbolFileDWARF objects to detect if this DWARF file is the one that can
1451 // resolve a compiler_type.
1452 bool SymbolFileDWARF::HasForwardDeclForClangType(
1453     const CompilerType &compiler_type) {
1454   CompilerType compiler_type_no_qualifiers =
1455       ClangUtil::RemoveFastQualifiers(compiler_type);
1456   if (GetForwardDeclClangTypeToDie().count(
1457           compiler_type_no_qualifiers.GetOpaqueQualType())) {
1458     return true;
1459   }
1460   TypeSystem *type_system = compiler_type.GetTypeSystem();
1461 
1462   ClangASTContext *clang_type_system =
1463       llvm::dyn_cast_or_null<ClangASTContext>(type_system);
1464   if (!clang_type_system)
1465     return false;
1466   DWARFASTParserClang *ast_parser =
1467       static_cast<DWARFASTParserClang *>(clang_type_system->GetDWARFParser());
1468   return ast_parser->GetClangASTImporter().CanImport(compiler_type);
1469 }
1470 
1471 bool SymbolFileDWARF::CompleteType(CompilerType &compiler_type) {
1472   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
1473 
1474   ClangASTContext *clang_type_system =
1475       llvm::dyn_cast_or_null<ClangASTContext>(compiler_type.GetTypeSystem());
1476   if (clang_type_system) {
1477     DWARFASTParserClang *ast_parser =
1478         static_cast<DWARFASTParserClang *>(clang_type_system->GetDWARFParser());
1479     if (ast_parser &&
1480         ast_parser->GetClangASTImporter().CanImport(compiler_type))
1481       return ast_parser->GetClangASTImporter().CompleteType(compiler_type);
1482   }
1483 
1484   // We have a struct/union/class/enum that needs to be fully resolved.
1485   CompilerType compiler_type_no_qualifiers =
1486       ClangUtil::RemoveFastQualifiers(compiler_type);
1487   auto die_it = GetForwardDeclClangTypeToDie().find(
1488       compiler_type_no_qualifiers.GetOpaqueQualType());
1489   if (die_it == GetForwardDeclClangTypeToDie().end()) {
1490     // We have already resolved this type...
1491     return true;
1492   }
1493 
1494   DWARFDIE dwarf_die = GetDIE(die_it->getSecond());
1495   if (dwarf_die) {
1496     // Once we start resolving this type, remove it from the forward
1497     // declaration map in case anyone child members or other types require this
1498     // type to get resolved. The type will get resolved when all of the calls
1499     // to SymbolFileDWARF::ResolveClangOpaqueTypeDefinition are done.
1500     GetForwardDeclClangTypeToDie().erase(die_it);
1501 
1502     Type *type = GetDIEToType().lookup(dwarf_die.GetDIE());
1503 
1504     Log *log(LogChannelDWARF::GetLogIfAny(DWARF_LOG_DEBUG_INFO |
1505                                           DWARF_LOG_TYPE_COMPLETION));
1506     if (log)
1507       GetObjectFile()->GetModule()->LogMessageVerboseBacktrace(
1508           log, "0x%8.8" PRIx64 ": %s '%s' resolving forward declaration...",
1509           dwarf_die.GetID(), dwarf_die.GetTagAsCString(),
1510           type->GetName().AsCString());
1511     assert(compiler_type);
1512     DWARFASTParser *dwarf_ast = dwarf_die.GetDWARFParser();
1513     if (dwarf_ast)
1514       return dwarf_ast->CompleteTypeFromDWARF(dwarf_die, type, compiler_type);
1515   }
1516   return false;
1517 }
1518 
1519 Type *SymbolFileDWARF::ResolveType(const DWARFDIE &die,
1520                                    bool assert_not_being_parsed,
1521                                    bool resolve_function_context) {
1522   if (die) {
1523     Type *type = GetTypeForDIE(die, resolve_function_context).get();
1524 
1525     if (assert_not_being_parsed) {
1526       if (type != DIE_IS_BEING_PARSED)
1527         return type;
1528 
1529       GetObjectFile()->GetModule()->ReportError(
1530           "Parsing a die that is being parsed die: 0x%8.8x: %s %s",
1531           die.GetOffset(), die.GetTagAsCString(), die.GetName());
1532 
1533     } else
1534       return type;
1535   }
1536   return nullptr;
1537 }
1538 
1539 CompileUnit *
1540 SymbolFileDWARF::GetCompUnitForDWARFCompUnit(DWARFUnit *dwarf_cu,
1541                                              uint32_t cu_idx) {
1542   // Check if the symbol vendor already knows about this compile unit?
1543   if (dwarf_cu->GetUserData() == NULL) {
1544     // The symbol vendor doesn't know about this compile unit, we need to parse
1545     // and add it to the symbol vendor object.
1546     return ParseCompileUnit(dwarf_cu, cu_idx).get();
1547   }
1548   return (CompileUnit *)dwarf_cu->GetUserData();
1549 }
1550 
1551 size_t SymbolFileDWARF::GetObjCMethodDIEOffsets(ConstString class_name,
1552                                                 DIEArray &method_die_offsets) {
1553   method_die_offsets.clear();
1554   m_index->GetObjCMethods(class_name, method_die_offsets);
1555   return method_die_offsets.size();
1556 }
1557 
1558 bool SymbolFileDWARF::GetFunction(const DWARFDIE &die, SymbolContext &sc) {
1559   sc.Clear(false);
1560 
1561   if (die) {
1562     // Check if the symbol vendor already knows about this compile unit?
1563     sc.comp_unit = GetCompUnitForDWARFCompUnit(die.GetCU(), UINT32_MAX);
1564 
1565     sc.function = sc.comp_unit->FindFunctionByUID(die.GetID()).get();
1566     if (sc.function == NULL)
1567       sc.function = ParseCompileUnitFunction(sc, die);
1568 
1569     if (sc.function) {
1570       sc.module_sp = sc.function->CalculateSymbolContextModule();
1571       return true;
1572     }
1573   }
1574 
1575   return false;
1576 }
1577 
1578 lldb::ModuleSP SymbolFileDWARF::GetDWOModule(ConstString name) {
1579   UpdateExternalModuleListIfNeeded();
1580   const auto &pos = m_external_type_modules.find(name);
1581   if (pos != m_external_type_modules.end())
1582     return pos->second;
1583   else
1584     return lldb::ModuleSP();
1585 }
1586 
1587 DWARFDIE
1588 SymbolFileDWARF::GetDIE(const DIERef &die_ref) {
1589   DWARFDebugInfo *debug_info = DebugInfo();
1590   if (debug_info)
1591     return debug_info->GetDIE(die_ref);
1592   else
1593     return DWARFDIE();
1594 }
1595 
1596 std::unique_ptr<SymbolFileDWARFDwo>
1597 SymbolFileDWARF::GetDwoSymbolFileForCompileUnit(
1598     DWARFUnit &dwarf_cu, const DWARFDebugInfoEntry &cu_die) {
1599   // If we are using a dSYM file, we never want the standard DWO files since
1600   // the -gmodules support uses the same DWO machanism to specify full debug
1601   // info files for modules.
1602   if (GetDebugMapSymfile())
1603     return nullptr;
1604 
1605   const char *dwo_name = cu_die.GetAttributeValueAsString(
1606       this, &dwarf_cu, DW_AT_GNU_dwo_name, nullptr);
1607   if (!dwo_name)
1608     return nullptr;
1609 
1610   SymbolFileDWARFDwp *dwp_symfile = GetDwpSymbolFile();
1611   if (dwp_symfile) {
1612     uint64_t dwo_id = cu_die.GetAttributeValueAsUnsigned(this, &dwarf_cu,
1613                                                          DW_AT_GNU_dwo_id, 0);
1614     std::unique_ptr<SymbolFileDWARFDwo> dwo_symfile =
1615         dwp_symfile->GetSymbolFileForDwoId(&dwarf_cu, dwo_id);
1616     if (dwo_symfile)
1617       return dwo_symfile;
1618   }
1619 
1620   FileSpec dwo_file(dwo_name, true);
1621   if (dwo_file.IsRelative()) {
1622     const char *comp_dir = cu_die.GetAttributeValueAsString(
1623         this, &dwarf_cu, DW_AT_comp_dir, nullptr);
1624     if (!comp_dir)
1625       return nullptr;
1626 
1627     dwo_file.SetFile(comp_dir, true, FileSpec::Style::native);
1628     dwo_file.AppendPathComponent(dwo_name);
1629   }
1630 
1631   if (!dwo_file.Exists())
1632     return nullptr;
1633 
1634   const lldb::offset_t file_offset = 0;
1635   DataBufferSP dwo_file_data_sp;
1636   lldb::offset_t dwo_file_data_offset = 0;
1637   ObjectFileSP dwo_obj_file = ObjectFile::FindPlugin(
1638       GetObjectFile()->GetModule(), &dwo_file, file_offset,
1639       dwo_file.GetByteSize(), dwo_file_data_sp, dwo_file_data_offset);
1640   if (dwo_obj_file == nullptr)
1641     return nullptr;
1642 
1643   return llvm::make_unique<SymbolFileDWARFDwo>(dwo_obj_file, &dwarf_cu);
1644 }
1645 
1646 void SymbolFileDWARF::UpdateExternalModuleListIfNeeded() {
1647   if (m_fetched_external_modules)
1648     return;
1649   m_fetched_external_modules = true;
1650 
1651   DWARFDebugInfo *debug_info = DebugInfo();
1652 
1653   const uint32_t num_compile_units = GetNumCompileUnits();
1654   for (uint32_t cu_idx = 0; cu_idx < num_compile_units; ++cu_idx) {
1655     DWARFUnit *dwarf_cu = debug_info->GetCompileUnitAtIndex(cu_idx);
1656 
1657     const DWARFBaseDIE die = dwarf_cu->GetUnitDIEOnly();
1658     if (die && die.HasChildren() == false) {
1659       const char *name = die.GetAttributeValueAsString(DW_AT_name, nullptr);
1660 
1661       if (name) {
1662         ConstString const_name(name);
1663         if (m_external_type_modules.find(const_name) ==
1664             m_external_type_modules.end()) {
1665           ModuleSP module_sp;
1666           const char *dwo_path =
1667               die.GetAttributeValueAsString(DW_AT_GNU_dwo_name, nullptr);
1668           if (dwo_path) {
1669             ModuleSpec dwo_module_spec;
1670             dwo_module_spec.GetFileSpec().SetFile(dwo_path, false,
1671                                                   FileSpec::Style::native);
1672             if (dwo_module_spec.GetFileSpec().IsRelative()) {
1673               const char *comp_dir =
1674                   die.GetAttributeValueAsString(DW_AT_comp_dir, nullptr);
1675               if (comp_dir) {
1676                 dwo_module_spec.GetFileSpec().SetFile(comp_dir, true,
1677                                                       FileSpec::Style::native);
1678                 dwo_module_spec.GetFileSpec().AppendPathComponent(dwo_path);
1679               }
1680             }
1681             dwo_module_spec.GetArchitecture() =
1682                 m_obj_file->GetModule()->GetArchitecture();
1683 
1684             // When LLDB loads "external" modules it looks at the presence of
1685             // DW_AT_GNU_dwo_name. However, when the already created module
1686             // (corresponding to .dwo itself) is being processed, it will see
1687             // the presence of DW_AT_GNU_dwo_name (which contains the name of
1688             // dwo file) and will try to call ModuleList::GetSharedModule
1689             // again. In some cases (i.e. for empty files) Clang 4.0 generates
1690             // a *.dwo file which has DW_AT_GNU_dwo_name, but no
1691             // DW_AT_comp_dir. In this case the method
1692             // ModuleList::GetSharedModule will fail and the warning will be
1693             // printed. However, as one can notice in this case we don't
1694             // actually need to try to load the already loaded module
1695             // (corresponding to .dwo) so we simply skip it.
1696             if (m_obj_file->GetFileSpec()
1697                         .GetFileNameExtension()
1698                         .GetStringRef() == ".dwo" &&
1699                 llvm::StringRef(m_obj_file->GetFileSpec().GetPath())
1700                     .endswith(dwo_module_spec.GetFileSpec().GetPath())) {
1701               continue;
1702             }
1703 
1704             Status error = ModuleList::GetSharedModule(
1705                 dwo_module_spec, module_sp, NULL, NULL, NULL);
1706             if (!module_sp) {
1707               GetObjectFile()->GetModule()->ReportWarning(
1708                   "0x%8.8x: unable to locate module needed for external types: "
1709                   "%s\nerror: %s\nDebugging will be degraded due to missing "
1710                   "types. Rebuilding your project will regenerate the needed "
1711                   "module files.",
1712                   die.GetOffset(),
1713                   dwo_module_spec.GetFileSpec().GetPath().c_str(),
1714                   error.AsCString("unknown error"));
1715             }
1716           }
1717           m_external_type_modules[const_name] = module_sp;
1718         }
1719       }
1720     }
1721   }
1722 }
1723 
1724 SymbolFileDWARF::GlobalVariableMap &SymbolFileDWARF::GetGlobalAranges() {
1725   if (!m_global_aranges_ap) {
1726     m_global_aranges_ap.reset(new GlobalVariableMap());
1727 
1728     ModuleSP module_sp = GetObjectFile()->GetModule();
1729     if (module_sp) {
1730       const size_t num_cus = module_sp->GetNumCompileUnits();
1731       for (size_t i = 0; i < num_cus; ++i) {
1732         CompUnitSP cu_sp = module_sp->GetCompileUnitAtIndex(i);
1733         if (cu_sp) {
1734           VariableListSP globals_sp = cu_sp->GetVariableList(true);
1735           if (globals_sp) {
1736             const size_t num_globals = globals_sp->GetSize();
1737             for (size_t g = 0; g < num_globals; ++g) {
1738               VariableSP var_sp = globals_sp->GetVariableAtIndex(g);
1739               if (var_sp && !var_sp->GetLocationIsConstantValueData()) {
1740                 const DWARFExpression &location = var_sp->LocationExpression();
1741                 Value location_result;
1742                 Status error;
1743                 if (location.Evaluate(nullptr, LLDB_INVALID_ADDRESS, nullptr,
1744                                       nullptr, location_result, &error)) {
1745                   if (location_result.GetValueType() ==
1746                       Value::eValueTypeFileAddress) {
1747                     lldb::addr_t file_addr =
1748                         location_result.GetScalar().ULongLong();
1749                     lldb::addr_t byte_size = 1;
1750                     if (var_sp->GetType())
1751                       byte_size = var_sp->GetType()->GetByteSize();
1752                     m_global_aranges_ap->Append(GlobalVariableMap::Entry(
1753                         file_addr, byte_size, var_sp.get()));
1754                   }
1755                 }
1756               }
1757             }
1758           }
1759         }
1760       }
1761     }
1762     m_global_aranges_ap->Sort();
1763   }
1764   return *m_global_aranges_ap;
1765 }
1766 
1767 uint32_t SymbolFileDWARF::ResolveSymbolContext(const Address &so_addr,
1768                                                uint32_t resolve_scope,
1769                                                SymbolContext &sc) {
1770   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
1771   Timer scoped_timer(func_cat,
1772                      "SymbolFileDWARF::"
1773                      "ResolveSymbolContext (so_addr = { "
1774                      "section = %p, offset = 0x%" PRIx64
1775                      " }, resolve_scope = 0x%8.8x)",
1776                      static_cast<void *>(so_addr.GetSection().get()),
1777                      so_addr.GetOffset(), resolve_scope);
1778   uint32_t resolved = 0;
1779   if (resolve_scope &
1780       (eSymbolContextCompUnit | eSymbolContextFunction | eSymbolContextBlock |
1781        eSymbolContextLineEntry | eSymbolContextVariable)) {
1782     lldb::addr_t file_vm_addr = so_addr.GetFileAddress();
1783 
1784     DWARFDebugInfo *debug_info = DebugInfo();
1785     if (debug_info) {
1786       const dw_offset_t cu_offset =
1787           debug_info->GetCompileUnitAranges().FindAddress(file_vm_addr);
1788       if (cu_offset == DW_INVALID_OFFSET) {
1789         // Global variables are not in the compile unit address ranges. The
1790         // only way to currently find global variables is to iterate over the
1791         // .debug_pubnames or the __apple_names table and find all items in
1792         // there that point to DW_TAG_variable DIEs and then find the address
1793         // that matches.
1794         if (resolve_scope & eSymbolContextVariable) {
1795           GlobalVariableMap &map = GetGlobalAranges();
1796           const GlobalVariableMap::Entry *entry =
1797               map.FindEntryThatContains(file_vm_addr);
1798           if (entry && entry->data) {
1799             Variable *variable = entry->data;
1800             SymbolContextScope *scc = variable->GetSymbolContextScope();
1801             if (scc) {
1802               scc->CalculateSymbolContext(&sc);
1803               sc.variable = variable;
1804             }
1805             return sc.GetResolvedMask();
1806           }
1807         }
1808       } else {
1809         uint32_t cu_idx = DW_INVALID_INDEX;
1810         DWARFUnit *dwarf_cu =
1811             debug_info->GetCompileUnit(cu_offset, &cu_idx);
1812         if (dwarf_cu) {
1813           sc.comp_unit = GetCompUnitForDWARFCompUnit(dwarf_cu, cu_idx);
1814           if (sc.comp_unit) {
1815             resolved |= eSymbolContextCompUnit;
1816 
1817             bool force_check_line_table = false;
1818             if (resolve_scope &
1819                 (eSymbolContextFunction | eSymbolContextBlock)) {
1820               DWARFDIE function_die = dwarf_cu->LookupAddress(file_vm_addr);
1821               DWARFDIE block_die;
1822               if (function_die) {
1823                 sc.function =
1824                     sc.comp_unit->FindFunctionByUID(function_die.GetID()).get();
1825                 if (sc.function == NULL)
1826                   sc.function = ParseCompileUnitFunction(sc, function_die);
1827 
1828                 if (sc.function && (resolve_scope & eSymbolContextBlock))
1829                   block_die = function_die.LookupDeepestBlock(file_vm_addr);
1830               } else {
1831                 // We might have had a compile unit that had discontiguous
1832                 // address ranges where the gaps are symbols that don't have
1833                 // any debug info. Discontiguous compile unit address ranges
1834                 // should only happen when there aren't other functions from
1835                 // other compile units in these gaps. This helps keep the size
1836                 // of the aranges down.
1837                 force_check_line_table = true;
1838               }
1839 
1840               if (sc.function != NULL) {
1841                 resolved |= eSymbolContextFunction;
1842 
1843                 if (resolve_scope & eSymbolContextBlock) {
1844                   Block &block = sc.function->GetBlock(true);
1845 
1846                   if (block_die)
1847                     sc.block = block.FindBlockByID(block_die.GetID());
1848                   else
1849                     sc.block = block.FindBlockByID(function_die.GetID());
1850                   if (sc.block)
1851                     resolved |= eSymbolContextBlock;
1852                 }
1853               }
1854             }
1855 
1856             if ((resolve_scope & eSymbolContextLineEntry) ||
1857                 force_check_line_table) {
1858               LineTable *line_table = sc.comp_unit->GetLineTable();
1859               if (line_table != NULL) {
1860                 // And address that makes it into this function should be in
1861                 // terms of this debug file if there is no debug map, or it
1862                 // will be an address in the .o file which needs to be fixed up
1863                 // to be in terms of the debug map executable. Either way,
1864                 // calling FixupAddress() will work for us.
1865                 Address exe_so_addr(so_addr);
1866                 if (FixupAddress(exe_so_addr)) {
1867                   if (line_table->FindLineEntryByAddress(exe_so_addr,
1868                                                          sc.line_entry)) {
1869                     resolved |= eSymbolContextLineEntry;
1870                   }
1871                 }
1872               }
1873             }
1874 
1875             if (force_check_line_table &&
1876                 !(resolved & eSymbolContextLineEntry)) {
1877               // We might have had a compile unit that had discontiguous
1878               // address ranges where the gaps are symbols that don't have any
1879               // debug info. Discontiguous compile unit address ranges should
1880               // only happen when there aren't other functions from other
1881               // compile units in these gaps. This helps keep the size of the
1882               // aranges down.
1883               sc.comp_unit = NULL;
1884               resolved &= ~eSymbolContextCompUnit;
1885             }
1886           } else {
1887             GetObjectFile()->GetModule()->ReportWarning(
1888                 "0x%8.8x: compile unit %u failed to create a valid "
1889                 "lldb_private::CompileUnit class.",
1890                 cu_offset, cu_idx);
1891           }
1892         }
1893       }
1894     }
1895   }
1896   return resolved;
1897 }
1898 
1899 uint32_t SymbolFileDWARF::ResolveSymbolContext(const FileSpec &file_spec,
1900                                                uint32_t line,
1901                                                bool check_inlines,
1902                                                uint32_t resolve_scope,
1903                                                SymbolContextList &sc_list) {
1904   const uint32_t prev_size = sc_list.GetSize();
1905   if (resolve_scope & eSymbolContextCompUnit) {
1906     DWARFDebugInfo *debug_info = DebugInfo();
1907     if (debug_info) {
1908       uint32_t cu_idx;
1909       DWARFUnit *dwarf_cu = NULL;
1910 
1911       for (cu_idx = 0;
1912            (dwarf_cu = debug_info->GetCompileUnitAtIndex(cu_idx)) != NULL;
1913            ++cu_idx) {
1914         CompileUnit *dc_cu = GetCompUnitForDWARFCompUnit(dwarf_cu, cu_idx);
1915         const bool full_match = (bool)file_spec.GetDirectory();
1916         bool file_spec_matches_cu_file_spec =
1917             dc_cu != NULL && FileSpec::Equal(file_spec, *dc_cu, full_match);
1918         if (check_inlines || file_spec_matches_cu_file_spec) {
1919           SymbolContext sc(m_obj_file->GetModule());
1920           sc.comp_unit = GetCompUnitForDWARFCompUnit(dwarf_cu, cu_idx);
1921           if (sc.comp_unit) {
1922             uint32_t file_idx = UINT32_MAX;
1923 
1924             // If we are looking for inline functions only and we don't find it
1925             // in the support files, we are done.
1926             if (check_inlines) {
1927               file_idx = sc.comp_unit->GetSupportFiles().FindFileIndex(
1928                   1, file_spec, true);
1929               if (file_idx == UINT32_MAX)
1930                 continue;
1931             }
1932 
1933             if (line != 0) {
1934               LineTable *line_table = sc.comp_unit->GetLineTable();
1935 
1936               if (line_table != NULL && line != 0) {
1937                 // We will have already looked up the file index if we are
1938                 // searching for inline entries.
1939                 if (!check_inlines)
1940                   file_idx = sc.comp_unit->GetSupportFiles().FindFileIndex(
1941                       1, file_spec, true);
1942 
1943                 if (file_idx != UINT32_MAX) {
1944                   uint32_t found_line;
1945                   uint32_t line_idx = line_table->FindLineEntryIndexByFileIndex(
1946                       0, file_idx, line, false, &sc.line_entry);
1947                   found_line = sc.line_entry.line;
1948 
1949                   while (line_idx != UINT32_MAX) {
1950                     sc.function = NULL;
1951                     sc.block = NULL;
1952                     if (resolve_scope &
1953                         (eSymbolContextFunction | eSymbolContextBlock)) {
1954                       const lldb::addr_t file_vm_addr =
1955                           sc.line_entry.range.GetBaseAddress().GetFileAddress();
1956                       if (file_vm_addr != LLDB_INVALID_ADDRESS) {
1957                         DWARFDIE function_die =
1958                             dwarf_cu->LookupAddress(file_vm_addr);
1959                         DWARFDIE block_die;
1960                         if (function_die) {
1961                           sc.function =
1962                               sc.comp_unit
1963                                   ->FindFunctionByUID(function_die.GetID())
1964                                   .get();
1965                           if (sc.function == NULL)
1966                             sc.function =
1967                                 ParseCompileUnitFunction(sc, function_die);
1968 
1969                           if (sc.function &&
1970                               (resolve_scope & eSymbolContextBlock))
1971                             block_die =
1972                                 function_die.LookupDeepestBlock(file_vm_addr);
1973                         }
1974 
1975                         if (sc.function != NULL) {
1976                           Block &block = sc.function->GetBlock(true);
1977 
1978                           if (block_die)
1979                             sc.block = block.FindBlockByID(block_die.GetID());
1980                           else if (function_die)
1981                             sc.block =
1982                                 block.FindBlockByID(function_die.GetID());
1983                         }
1984                       }
1985                     }
1986 
1987                     sc_list.Append(sc);
1988                     line_idx = line_table->FindLineEntryIndexByFileIndex(
1989                         line_idx + 1, file_idx, found_line, true,
1990                         &sc.line_entry);
1991                   }
1992                 }
1993               } else if (file_spec_matches_cu_file_spec && !check_inlines) {
1994                 // only append the context if we aren't looking for inline call
1995                 // sites by file and line and if the file spec matches that of
1996                 // the compile unit
1997                 sc_list.Append(sc);
1998               }
1999             } else if (file_spec_matches_cu_file_spec && !check_inlines) {
2000               // only append the context if we aren't looking for inline call
2001               // sites by file and line and if the file spec matches that of
2002               // the compile unit
2003               sc_list.Append(sc);
2004             }
2005 
2006             if (!check_inlines)
2007               break;
2008           }
2009         }
2010       }
2011     }
2012   }
2013   return sc_list.GetSize() - prev_size;
2014 }
2015 
2016 void SymbolFileDWARF::PreloadSymbols() {
2017   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
2018   m_index->Preload();
2019 }
2020 
2021 std::recursive_mutex &SymbolFileDWARF::GetModuleMutex() const {
2022   lldb::ModuleSP module_sp(m_debug_map_module_wp.lock());
2023   if (module_sp)
2024     return module_sp->GetMutex();
2025   return GetObjectFile()->GetModule()->GetMutex();
2026 }
2027 
2028 bool SymbolFileDWARF::DeclContextMatchesThisSymbolFile(
2029     const lldb_private::CompilerDeclContext *decl_ctx) {
2030   if (decl_ctx == nullptr || !decl_ctx->IsValid()) {
2031     // Invalid namespace decl which means we aren't matching only things in
2032     // this symbol file, so return true to indicate it matches this symbol
2033     // file.
2034     return true;
2035   }
2036 
2037   TypeSystem *decl_ctx_type_system = decl_ctx->GetTypeSystem();
2038   TypeSystem *type_system = GetTypeSystemForLanguage(
2039       decl_ctx_type_system->GetMinimumLanguage(nullptr));
2040   if (decl_ctx_type_system == type_system)
2041     return true; // The type systems match, return true
2042 
2043   // The namespace AST was valid, and it does not match...
2044   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2045 
2046   if (log)
2047     GetObjectFile()->GetModule()->LogMessage(
2048         log, "Valid namespace does not match symbol file");
2049 
2050   return false;
2051 }
2052 
2053 uint32_t SymbolFileDWARF::FindGlobalVariables(
2054     const ConstString &name, const CompilerDeclContext *parent_decl_ctx,
2055     uint32_t max_matches, VariableList &variables) {
2056   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2057 
2058   if (log)
2059     GetObjectFile()->GetModule()->LogMessage(
2060         log,
2061         "SymbolFileDWARF::FindGlobalVariables (name=\"%s\", "
2062         "parent_decl_ctx=%p, max_matches=%u, variables)",
2063         name.GetCString(), static_cast<const void *>(parent_decl_ctx),
2064         max_matches);
2065 
2066   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
2067     return 0;
2068 
2069   DWARFDebugInfo *info = DebugInfo();
2070   if (info == NULL)
2071     return 0;
2072 
2073   // Remember how many variables are in the list before we search.
2074   const uint32_t original_size = variables.GetSize();
2075 
2076   llvm::StringRef basename;
2077   llvm::StringRef context;
2078 
2079   if (!CPlusPlusLanguage::ExtractContextAndIdentifier(name.GetCString(),
2080                                                       context, basename))
2081     basename = name.GetStringRef();
2082 
2083   DIEArray die_offsets;
2084   m_index->GetGlobalVariables(ConstString(basename), die_offsets);
2085   const size_t num_die_matches = die_offsets.size();
2086   if (num_die_matches) {
2087     SymbolContext sc;
2088     sc.module_sp = m_obj_file->GetModule();
2089     assert(sc.module_sp);
2090 
2091     // Loop invariant: Variables up to this index have been checked for context
2092     // matches.
2093     uint32_t pruned_idx = original_size;
2094 
2095     bool done = false;
2096     for (size_t i = 0; i < num_die_matches && !done; ++i) {
2097       const DIERef &die_ref = die_offsets[i];
2098       DWARFDIE die = GetDIE(die_ref);
2099 
2100       if (die) {
2101         switch (die.Tag()) {
2102         default:
2103         case DW_TAG_subprogram:
2104         case DW_TAG_inlined_subroutine:
2105         case DW_TAG_try_block:
2106         case DW_TAG_catch_block:
2107           break;
2108 
2109         case DW_TAG_variable: {
2110           sc.comp_unit = GetCompUnitForDWARFCompUnit(die.GetCU(), UINT32_MAX);
2111 
2112           if (parent_decl_ctx) {
2113             DWARFASTParser *dwarf_ast = die.GetDWARFParser();
2114             if (dwarf_ast) {
2115               CompilerDeclContext actual_parent_decl_ctx =
2116                   dwarf_ast->GetDeclContextContainingUIDFromDWARF(die);
2117               if (!actual_parent_decl_ctx ||
2118                   actual_parent_decl_ctx != *parent_decl_ctx)
2119                 continue;
2120             }
2121           }
2122 
2123           ParseVariables(sc, die, LLDB_INVALID_ADDRESS, false, false,
2124                          &variables);
2125           while (pruned_idx < variables.GetSize()) {
2126             VariableSP var_sp = variables.GetVariableAtIndex(pruned_idx);
2127             if (var_sp->GetName().GetStringRef().contains(name.GetStringRef()))
2128               ++pruned_idx;
2129             else
2130               variables.RemoveVariableAtIndex(pruned_idx);
2131           }
2132 
2133           if (variables.GetSize() - original_size >= max_matches)
2134             done = true;
2135         } break;
2136         }
2137       } else {
2138         m_index->ReportInvalidDIEOffset(die_ref.die_offset,
2139                                         name.GetStringRef());
2140       }
2141     }
2142   }
2143 
2144   // Return the number of variable that were appended to the list
2145   const uint32_t num_matches = variables.GetSize() - original_size;
2146   if (log && num_matches > 0) {
2147     GetObjectFile()->GetModule()->LogMessage(
2148         log,
2149         "SymbolFileDWARF::FindGlobalVariables (name=\"%s\", "
2150         "parent_decl_ctx=%p, max_matches=%u, variables) => %u",
2151         name.GetCString(), static_cast<const void *>(parent_decl_ctx),
2152         max_matches, num_matches);
2153   }
2154   return num_matches;
2155 }
2156 
2157 uint32_t SymbolFileDWARF::FindGlobalVariables(const RegularExpression &regex,
2158                                               uint32_t max_matches,
2159                                               VariableList &variables) {
2160   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2161 
2162   if (log) {
2163     GetObjectFile()->GetModule()->LogMessage(
2164         log,
2165         "SymbolFileDWARF::FindGlobalVariables (regex=\"%s\", "
2166         "max_matches=%u, variables)",
2167         regex.GetText().str().c_str(), max_matches);
2168   }
2169 
2170   DWARFDebugInfo *info = DebugInfo();
2171   if (info == NULL)
2172     return 0;
2173 
2174   // Remember how many variables are in the list before we search.
2175   const uint32_t original_size = variables.GetSize();
2176 
2177   DIEArray die_offsets;
2178   m_index->GetGlobalVariables(regex, die_offsets);
2179 
2180   SymbolContext sc;
2181   sc.module_sp = m_obj_file->GetModule();
2182   assert(sc.module_sp);
2183 
2184   const size_t num_matches = die_offsets.size();
2185   if (num_matches) {
2186     for (size_t i = 0; i < num_matches; ++i) {
2187       const DIERef &die_ref = die_offsets[i];
2188       DWARFDIE die = GetDIE(die_ref);
2189 
2190       if (die) {
2191         sc.comp_unit = GetCompUnitForDWARFCompUnit(die.GetCU(), UINT32_MAX);
2192 
2193         ParseVariables(sc, die, LLDB_INVALID_ADDRESS, false, false, &variables);
2194 
2195         if (variables.GetSize() - original_size >= max_matches)
2196           break;
2197       } else
2198         m_index->ReportInvalidDIEOffset(die_ref.die_offset, regex.GetText());
2199     }
2200   }
2201 
2202   // Return the number of variable that were appended to the list
2203   return variables.GetSize() - original_size;
2204 }
2205 
2206 bool SymbolFileDWARF::ResolveFunction(const DWARFDIE &orig_die,
2207                                       bool include_inlines,
2208                                       SymbolContextList &sc_list) {
2209   SymbolContext sc;
2210 
2211   if (!orig_die)
2212     return false;
2213 
2214   // If we were passed a die that is not a function, just return false...
2215   if (!(orig_die.Tag() == DW_TAG_subprogram ||
2216         (include_inlines && orig_die.Tag() == DW_TAG_inlined_subroutine)))
2217     return false;
2218 
2219   DWARFDIE die = orig_die;
2220   DWARFDIE inlined_die;
2221   if (die.Tag() == DW_TAG_inlined_subroutine) {
2222     inlined_die = die;
2223 
2224     while (1) {
2225       die = die.GetParent();
2226 
2227       if (die) {
2228         if (die.Tag() == DW_TAG_subprogram)
2229           break;
2230       } else
2231         break;
2232     }
2233   }
2234   assert(die && die.Tag() == DW_TAG_subprogram);
2235   if (GetFunction(die, sc)) {
2236     Address addr;
2237     // Parse all blocks if needed
2238     if (inlined_die) {
2239       Block &function_block = sc.function->GetBlock(true);
2240       sc.block = function_block.FindBlockByID(inlined_die.GetID());
2241       if (sc.block == NULL)
2242         sc.block = function_block.FindBlockByID(inlined_die.GetOffset());
2243       if (sc.block == NULL || sc.block->GetStartAddress(addr) == false)
2244         addr.Clear();
2245     } else {
2246       sc.block = NULL;
2247       addr = sc.function->GetAddressRange().GetBaseAddress();
2248     }
2249 
2250     if (addr.IsValid()) {
2251       sc_list.Append(sc);
2252       return true;
2253     }
2254   }
2255 
2256   return false;
2257 }
2258 
2259 bool SymbolFileDWARF::DIEInDeclContext(const CompilerDeclContext *decl_ctx,
2260                                        const DWARFDIE &die) {
2261   // If we have no parent decl context to match this DIE matches, and if the
2262   // parent decl context isn't valid, we aren't trying to look for any
2263   // particular decl context so any die matches.
2264   if (decl_ctx == nullptr || !decl_ctx->IsValid())
2265     return true;
2266 
2267   if (die) {
2268     DWARFASTParser *dwarf_ast = die.GetDWARFParser();
2269     if (dwarf_ast) {
2270       CompilerDeclContext actual_decl_ctx =
2271           dwarf_ast->GetDeclContextContainingUIDFromDWARF(die);
2272       if (actual_decl_ctx)
2273         return actual_decl_ctx == *decl_ctx;
2274     }
2275   }
2276   return false;
2277 }
2278 
2279 uint32_t
2280 SymbolFileDWARF::FindFunctions(const ConstString &name,
2281                                const CompilerDeclContext *parent_decl_ctx,
2282                                uint32_t name_type_mask, bool include_inlines,
2283                                bool append, SymbolContextList &sc_list) {
2284   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
2285   Timer scoped_timer(func_cat, "SymbolFileDWARF::FindFunctions (name = '%s')",
2286                      name.AsCString());
2287 
2288   // eFunctionNameTypeAuto should be pre-resolved by a call to
2289   // Module::LookupInfo::LookupInfo()
2290   assert((name_type_mask & eFunctionNameTypeAuto) == 0);
2291 
2292   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2293 
2294   if (log) {
2295     GetObjectFile()->GetModule()->LogMessage(
2296         log, "SymbolFileDWARF::FindFunctions (name=\"%s\", "
2297              "name_type_mask=0x%x, append=%u, sc_list)",
2298         name.GetCString(), name_type_mask, append);
2299   }
2300 
2301   // If we aren't appending the results to this list, then clear the list
2302   if (!append)
2303     sc_list.Clear();
2304 
2305   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
2306     return 0;
2307 
2308   // If name is empty then we won't find anything.
2309   if (name.IsEmpty())
2310     return 0;
2311 
2312   // Remember how many sc_list are in the list before we search in case we are
2313   // appending the results to a variable list.
2314 
2315   const uint32_t original_size = sc_list.GetSize();
2316 
2317   DWARFDebugInfo *info = DebugInfo();
2318   if (info == NULL)
2319     return 0;
2320 
2321   llvm::DenseSet<const DWARFDebugInfoEntry *> resolved_dies;
2322   DIEArray offsets;
2323   CompilerDeclContext empty_decl_ctx;
2324   if (!parent_decl_ctx)
2325     parent_decl_ctx = &empty_decl_ctx;
2326 
2327   std::vector<DWARFDIE> dies;
2328   m_index->GetFunctions(name, *info, *parent_decl_ctx, name_type_mask, dies);
2329   for (const DWARFDIE &die: dies) {
2330     if (resolved_dies.insert(die.GetDIE()).second)
2331       ResolveFunction(die, include_inlines, sc_list);
2332   }
2333 
2334   // Return the number of variable that were appended to the list
2335   const uint32_t num_matches = sc_list.GetSize() - original_size;
2336 
2337   if (log && num_matches > 0) {
2338     GetObjectFile()->GetModule()->LogMessage(
2339         log, "SymbolFileDWARF::FindFunctions (name=\"%s\", "
2340              "name_type_mask=0x%x, include_inlines=%d, append=%u, sc_list) => "
2341              "%u",
2342         name.GetCString(), name_type_mask, include_inlines, append,
2343         num_matches);
2344   }
2345   return num_matches;
2346 }
2347 
2348 uint32_t SymbolFileDWARF::FindFunctions(const RegularExpression &regex,
2349                                         bool include_inlines, bool append,
2350                                         SymbolContextList &sc_list) {
2351   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
2352   Timer scoped_timer(func_cat, "SymbolFileDWARF::FindFunctions (regex = '%s')",
2353                      regex.GetText().str().c_str());
2354 
2355   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2356 
2357   if (log) {
2358     GetObjectFile()->GetModule()->LogMessage(
2359         log,
2360         "SymbolFileDWARF::FindFunctions (regex=\"%s\", append=%u, sc_list)",
2361         regex.GetText().str().c_str(), append);
2362   }
2363 
2364   // If we aren't appending the results to this list, then clear the list
2365   if (!append)
2366     sc_list.Clear();
2367 
2368   DWARFDebugInfo *info = DebugInfo();
2369   if (!info)
2370     return 0;
2371 
2372   // Remember how many sc_list are in the list before we search in case we are
2373   // appending the results to a variable list.
2374   uint32_t original_size = sc_list.GetSize();
2375 
2376   DIEArray offsets;
2377   m_index->GetFunctions(regex, offsets);
2378 
2379   llvm::DenseSet<const DWARFDebugInfoEntry *> resolved_dies;
2380   for (DIERef ref : offsets) {
2381     DWARFDIE die = info->GetDIE(ref);
2382     if (!die) {
2383       m_index->ReportInvalidDIEOffset(ref.die_offset, regex.GetText());
2384       continue;
2385     }
2386     if (resolved_dies.insert(die.GetDIE()).second)
2387       ResolveFunction(die, include_inlines, sc_list);
2388   }
2389 
2390   // Return the number of variable that were appended to the list
2391   return sc_list.GetSize() - original_size;
2392 }
2393 
2394 void SymbolFileDWARF::GetMangledNamesForFunction(
2395     const std::string &scope_qualified_name,
2396     std::vector<ConstString> &mangled_names) {
2397   DWARFDebugInfo *info = DebugInfo();
2398   uint32_t num_comp_units = 0;
2399   if (info)
2400     num_comp_units = info->GetNumCompileUnits();
2401 
2402   for (uint32_t i = 0; i < num_comp_units; i++) {
2403     DWARFUnit *cu = info->GetCompileUnitAtIndex(i);
2404     if (cu == nullptr)
2405       continue;
2406 
2407     SymbolFileDWARFDwo *dwo = cu->GetDwoSymbolFile();
2408     if (dwo)
2409       dwo->GetMangledNamesForFunction(scope_qualified_name, mangled_names);
2410   }
2411 
2412   NameToOffsetMap::iterator iter =
2413       m_function_scope_qualified_name_map.find(scope_qualified_name);
2414   if (iter == m_function_scope_qualified_name_map.end())
2415     return;
2416 
2417   DIERefSetSP set_sp = (*iter).second;
2418   std::set<DIERef>::iterator set_iter;
2419   for (set_iter = set_sp->begin(); set_iter != set_sp->end(); set_iter++) {
2420     DWARFDIE die = DebugInfo()->GetDIE(*set_iter);
2421     mangled_names.push_back(ConstString(die.GetMangledName()));
2422   }
2423 }
2424 
2425 uint32_t SymbolFileDWARF::FindTypes(
2426     const SymbolContext &sc, const ConstString &name,
2427     const CompilerDeclContext *parent_decl_ctx, bool append,
2428     uint32_t max_matches,
2429     llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
2430     TypeMap &types) {
2431   // If we aren't appending the results to this list, then clear the list
2432   if (!append)
2433     types.Clear();
2434 
2435   // Make sure we haven't already searched this SymbolFile before...
2436   if (searched_symbol_files.count(this))
2437     return 0;
2438   else
2439     searched_symbol_files.insert(this);
2440 
2441   DWARFDebugInfo *info = DebugInfo();
2442   if (info == NULL)
2443     return 0;
2444 
2445   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2446 
2447   if (log) {
2448     if (parent_decl_ctx)
2449       GetObjectFile()->GetModule()->LogMessage(
2450           log, "SymbolFileDWARF::FindTypes (sc, name=\"%s\", parent_decl_ctx = "
2451                "%p (\"%s\"), append=%u, max_matches=%u, type_list)",
2452           name.GetCString(), static_cast<const void *>(parent_decl_ctx),
2453           parent_decl_ctx->GetName().AsCString("<NULL>"), append, max_matches);
2454     else
2455       GetObjectFile()->GetModule()->LogMessage(
2456           log, "SymbolFileDWARF::FindTypes (sc, name=\"%s\", parent_decl_ctx = "
2457                "NULL, append=%u, max_matches=%u, type_list)",
2458           name.GetCString(), append, max_matches);
2459   }
2460 
2461   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
2462     return 0;
2463 
2464   DIEArray die_offsets;
2465   m_index->GetTypes(name, die_offsets);
2466   const size_t num_die_matches = die_offsets.size();
2467 
2468   if (num_die_matches) {
2469     const uint32_t initial_types_size = types.GetSize();
2470     for (size_t i = 0; i < num_die_matches; ++i) {
2471       const DIERef &die_ref = die_offsets[i];
2472       DWARFDIE die = GetDIE(die_ref);
2473 
2474       if (die) {
2475         if (!DIEInDeclContext(parent_decl_ctx, die))
2476           continue; // The containing decl contexts don't match
2477 
2478         Type *matching_type = ResolveType(die, true, true);
2479         if (matching_type) {
2480           // We found a type pointer, now find the shared pointer form our type
2481           // list
2482           types.InsertUnique(matching_type->shared_from_this());
2483           if (types.GetSize() >= max_matches)
2484             break;
2485         }
2486       } else {
2487         m_index->ReportInvalidDIEOffset(die_ref.die_offset,
2488                                         name.GetStringRef());
2489       }
2490     }
2491     const uint32_t num_matches = types.GetSize() - initial_types_size;
2492     if (log && num_matches) {
2493       if (parent_decl_ctx) {
2494         GetObjectFile()->GetModule()->LogMessage(
2495             log, "SymbolFileDWARF::FindTypes (sc, name=\"%s\", parent_decl_ctx "
2496                  "= %p (\"%s\"), append=%u, max_matches=%u, type_list) => %u",
2497             name.GetCString(), static_cast<const void *>(parent_decl_ctx),
2498             parent_decl_ctx->GetName().AsCString("<NULL>"), append, max_matches,
2499             num_matches);
2500       } else {
2501         GetObjectFile()->GetModule()->LogMessage(
2502             log, "SymbolFileDWARF::FindTypes (sc, name=\"%s\", parent_decl_ctx "
2503                  "= NULL, append=%u, max_matches=%u, type_list) => %u",
2504             name.GetCString(), append, max_matches, num_matches);
2505       }
2506     }
2507     return num_matches;
2508   } else {
2509     UpdateExternalModuleListIfNeeded();
2510 
2511     for (const auto &pair : m_external_type_modules) {
2512       ModuleSP external_module_sp = pair.second;
2513       if (external_module_sp) {
2514         SymbolVendor *sym_vendor = external_module_sp->GetSymbolVendor();
2515         if (sym_vendor) {
2516           const uint32_t num_external_matches =
2517               sym_vendor->FindTypes(sc, name, parent_decl_ctx, append,
2518                                     max_matches, searched_symbol_files, types);
2519           if (num_external_matches)
2520             return num_external_matches;
2521         }
2522       }
2523     }
2524   }
2525 
2526   return 0;
2527 }
2528 
2529 size_t SymbolFileDWARF::FindTypes(const std::vector<CompilerContext> &context,
2530                                   bool append, TypeMap &types) {
2531   if (!append)
2532     types.Clear();
2533 
2534   if (context.empty())
2535     return 0;
2536 
2537   ConstString name = context.back().name;
2538 
2539   if (!name)
2540     return 0;
2541 
2542   DIEArray die_offsets;
2543   m_index->GetTypes(name, die_offsets);
2544   const size_t num_die_matches = die_offsets.size();
2545 
2546   if (num_die_matches) {
2547     size_t num_matches = 0;
2548     for (size_t i = 0; i < num_die_matches; ++i) {
2549       const DIERef &die_ref = die_offsets[i];
2550       DWARFDIE die = GetDIE(die_ref);
2551 
2552       if (die) {
2553         std::vector<CompilerContext> die_context;
2554         die.GetDWOContext(die_context);
2555         if (die_context != context)
2556           continue;
2557 
2558         Type *matching_type = ResolveType(die, true, true);
2559         if (matching_type) {
2560           // We found a type pointer, now find the shared pointer form our type
2561           // list
2562           types.InsertUnique(matching_type->shared_from_this());
2563           ++num_matches;
2564         }
2565       } else {
2566         m_index->ReportInvalidDIEOffset(die_ref.die_offset,
2567                                         name.GetStringRef());
2568       }
2569     }
2570     return num_matches;
2571   }
2572   return 0;
2573 }
2574 
2575 CompilerDeclContext
2576 SymbolFileDWARF::FindNamespace(const SymbolContext &sc, const ConstString &name,
2577                                const CompilerDeclContext *parent_decl_ctx) {
2578   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_LOOKUPS));
2579 
2580   if (log) {
2581     GetObjectFile()->GetModule()->LogMessage(
2582         log, "SymbolFileDWARF::FindNamespace (sc, name=\"%s\")",
2583         name.GetCString());
2584   }
2585 
2586   CompilerDeclContext namespace_decl_ctx;
2587 
2588   if (!DeclContextMatchesThisSymbolFile(parent_decl_ctx))
2589     return namespace_decl_ctx;
2590 
2591   DWARFDebugInfo *info = DebugInfo();
2592   if (info) {
2593     DIEArray die_offsets;
2594     m_index->GetNamespaces(name, die_offsets);
2595     const size_t num_matches = die_offsets.size();
2596     if (num_matches) {
2597       for (size_t i = 0; i < num_matches; ++i) {
2598         const DIERef &die_ref = die_offsets[i];
2599         DWARFDIE die = GetDIE(die_ref);
2600 
2601         if (die) {
2602           if (!DIEInDeclContext(parent_decl_ctx, die))
2603             continue; // The containing decl contexts don't match
2604 
2605           DWARFASTParser *dwarf_ast = die.GetDWARFParser();
2606           if (dwarf_ast) {
2607             namespace_decl_ctx = dwarf_ast->GetDeclContextForUIDFromDWARF(die);
2608             if (namespace_decl_ctx)
2609               break;
2610           }
2611         } else {
2612           m_index->ReportInvalidDIEOffset(die_ref.die_offset,
2613                                           name.GetStringRef());
2614         }
2615       }
2616     }
2617   }
2618   if (log && namespace_decl_ctx) {
2619     GetObjectFile()->GetModule()->LogMessage(
2620         log, "SymbolFileDWARF::FindNamespace (sc, name=\"%s\") => "
2621              "CompilerDeclContext(%p/%p) \"%s\"",
2622         name.GetCString(),
2623         static_cast<const void *>(namespace_decl_ctx.GetTypeSystem()),
2624         static_cast<const void *>(namespace_decl_ctx.GetOpaqueDeclContext()),
2625         namespace_decl_ctx.GetName().AsCString("<NULL>"));
2626   }
2627 
2628   return namespace_decl_ctx;
2629 }
2630 
2631 TypeSP SymbolFileDWARF::GetTypeForDIE(const DWARFDIE &die,
2632                                       bool resolve_function_context) {
2633   TypeSP type_sp;
2634   if (die) {
2635     Type *type_ptr = GetDIEToType().lookup(die.GetDIE());
2636     if (type_ptr == NULL) {
2637       CompileUnit *lldb_cu = GetCompUnitForDWARFCompUnit(die.GetCU());
2638       assert(lldb_cu);
2639       SymbolContext sc(lldb_cu);
2640       const DWARFDebugInfoEntry *parent_die = die.GetParent().GetDIE();
2641       while (parent_die != nullptr) {
2642         if (parent_die->Tag() == DW_TAG_subprogram)
2643           break;
2644         parent_die = parent_die->GetParent();
2645       }
2646       SymbolContext sc_backup = sc;
2647       if (resolve_function_context && parent_die != nullptr &&
2648           !GetFunction(DWARFDIE(die.GetCU(), parent_die), sc))
2649         sc = sc_backup;
2650 
2651       type_sp = ParseType(sc, die, NULL);
2652     } else if (type_ptr != DIE_IS_BEING_PARSED) {
2653       // Grab the existing type from the master types lists
2654       type_sp = type_ptr->shared_from_this();
2655     }
2656   }
2657   return type_sp;
2658 }
2659 
2660 DWARFDIE
2661 SymbolFileDWARF::GetDeclContextDIEContainingDIE(const DWARFDIE &orig_die) {
2662   if (orig_die) {
2663     DWARFDIE die = orig_die;
2664 
2665     while (die) {
2666       // If this is the original DIE that we are searching for a declaration
2667       // for, then don't look in the cache as we don't want our own decl
2668       // context to be our decl context...
2669       if (orig_die != die) {
2670         switch (die.Tag()) {
2671         case DW_TAG_compile_unit:
2672         case DW_TAG_partial_unit:
2673         case DW_TAG_namespace:
2674         case DW_TAG_structure_type:
2675         case DW_TAG_union_type:
2676         case DW_TAG_class_type:
2677         case DW_TAG_lexical_block:
2678         case DW_TAG_subprogram:
2679           return die;
2680         case DW_TAG_inlined_subroutine: {
2681           DWARFDIE abs_die = die.GetReferencedDIE(DW_AT_abstract_origin);
2682           if (abs_die) {
2683             return abs_die;
2684           }
2685           break;
2686         }
2687         default:
2688           break;
2689         }
2690       }
2691 
2692       DWARFDIE spec_die = die.GetReferencedDIE(DW_AT_specification);
2693       if (spec_die) {
2694         DWARFDIE decl_ctx_die = GetDeclContextDIEContainingDIE(spec_die);
2695         if (decl_ctx_die)
2696           return decl_ctx_die;
2697       }
2698 
2699       DWARFDIE abs_die = die.GetReferencedDIE(DW_AT_abstract_origin);
2700       if (abs_die) {
2701         DWARFDIE decl_ctx_die = GetDeclContextDIEContainingDIE(abs_die);
2702         if (decl_ctx_die)
2703           return decl_ctx_die;
2704       }
2705 
2706       die = die.GetParent();
2707     }
2708   }
2709   return DWARFDIE();
2710 }
2711 
2712 Symbol *
2713 SymbolFileDWARF::GetObjCClassSymbol(const ConstString &objc_class_name) {
2714   Symbol *objc_class_symbol = NULL;
2715   if (m_obj_file) {
2716     Symtab *symtab = m_obj_file->GetSymtab();
2717     if (symtab) {
2718       objc_class_symbol = symtab->FindFirstSymbolWithNameAndType(
2719           objc_class_name, eSymbolTypeObjCClass, Symtab::eDebugNo,
2720           Symtab::eVisibilityAny);
2721     }
2722   }
2723   return objc_class_symbol;
2724 }
2725 
2726 // Some compilers don't emit the DW_AT_APPLE_objc_complete_type attribute. If
2727 // they don't then we can end up looking through all class types for a complete
2728 // type and never find the full definition. We need to know if this attribute
2729 // is supported, so we determine this here and cache th result. We also need to
2730 // worry about the debug map
2731 // DWARF file
2732 // if we are doing darwin DWARF in .o file debugging.
2733 bool SymbolFileDWARF::Supports_DW_AT_APPLE_objc_complete_type(
2734     DWARFUnit *cu) {
2735   if (m_supports_DW_AT_APPLE_objc_complete_type == eLazyBoolCalculate) {
2736     m_supports_DW_AT_APPLE_objc_complete_type = eLazyBoolNo;
2737     if (cu && cu->Supports_DW_AT_APPLE_objc_complete_type())
2738       m_supports_DW_AT_APPLE_objc_complete_type = eLazyBoolYes;
2739     else {
2740       DWARFDebugInfo *debug_info = DebugInfo();
2741       const uint32_t num_compile_units = GetNumCompileUnits();
2742       for (uint32_t cu_idx = 0; cu_idx < num_compile_units; ++cu_idx) {
2743         DWARFUnit *dwarf_cu = debug_info->GetCompileUnitAtIndex(cu_idx);
2744         if (dwarf_cu != cu &&
2745             dwarf_cu->Supports_DW_AT_APPLE_objc_complete_type()) {
2746           m_supports_DW_AT_APPLE_objc_complete_type = eLazyBoolYes;
2747           break;
2748         }
2749       }
2750     }
2751     if (m_supports_DW_AT_APPLE_objc_complete_type == eLazyBoolNo &&
2752         GetDebugMapSymfile())
2753       return m_debug_map_symfile->Supports_DW_AT_APPLE_objc_complete_type(this);
2754   }
2755   return m_supports_DW_AT_APPLE_objc_complete_type == eLazyBoolYes;
2756 }
2757 
2758 // This function can be used when a DIE is found that is a forward declaration
2759 // DIE and we want to try and find a type that has the complete definition.
2760 TypeSP SymbolFileDWARF::FindCompleteObjCDefinitionTypeForDIE(
2761     const DWARFDIE &die, const ConstString &type_name,
2762     bool must_be_implementation) {
2763 
2764   TypeSP type_sp;
2765 
2766   if (!type_name || (must_be_implementation && !GetObjCClassSymbol(type_name)))
2767     return type_sp;
2768 
2769   DIEArray die_offsets;
2770   m_index->GetCompleteObjCClass(type_name, must_be_implementation, die_offsets);
2771 
2772   const size_t num_matches = die_offsets.size();
2773 
2774   if (num_matches) {
2775     for (size_t i = 0; i < num_matches; ++i) {
2776       const DIERef &die_ref = die_offsets[i];
2777       DWARFDIE type_die = GetDIE(die_ref);
2778 
2779       if (type_die) {
2780         bool try_resolving_type = false;
2781 
2782         // Don't try and resolve the DIE we are looking for with the DIE
2783         // itself!
2784         if (type_die != die) {
2785           switch (type_die.Tag()) {
2786           case DW_TAG_class_type:
2787           case DW_TAG_structure_type:
2788             try_resolving_type = true;
2789             break;
2790           default:
2791             break;
2792           }
2793         }
2794 
2795         if (try_resolving_type) {
2796           if (must_be_implementation &&
2797               type_die.Supports_DW_AT_APPLE_objc_complete_type())
2798             try_resolving_type = type_die.GetAttributeValueAsUnsigned(
2799                 DW_AT_APPLE_objc_complete_type, 0);
2800 
2801           if (try_resolving_type) {
2802             Type *resolved_type = ResolveType(type_die, false, true);
2803             if (resolved_type && resolved_type != DIE_IS_BEING_PARSED) {
2804               DEBUG_PRINTF("resolved 0x%8.8" PRIx64 " from %s to 0x%8.8" PRIx64
2805                            " (cu 0x%8.8" PRIx64 ")\n",
2806                            die.GetID(),
2807                            m_obj_file->GetFileSpec().GetFilename().AsCString(
2808                                "<Unknown>"),
2809                            type_die.GetID(), type_cu->GetID());
2810 
2811               if (die)
2812                 GetDIEToType()[die.GetDIE()] = resolved_type;
2813               type_sp = resolved_type->shared_from_this();
2814               break;
2815             }
2816           }
2817         }
2818       } else {
2819         m_index->ReportInvalidDIEOffset(die_ref.die_offset,
2820                                         type_name.GetStringRef());
2821       }
2822     }
2823   }
2824   return type_sp;
2825 }
2826 
2827 //----------------------------------------------------------------------
2828 // This function helps to ensure that the declaration contexts match for two
2829 // different DIEs. Often times debug information will refer to a forward
2830 // declaration of a type (the equivalent of "struct my_struct;". There will
2831 // often be a declaration of that type elsewhere that has the full definition.
2832 // When we go looking for the full type "my_struct", we will find one or more
2833 // matches in the accelerator tables and we will then need to make sure the
2834 // type was in the same declaration context as the original DIE. This function
2835 // can efficiently compare two DIEs and will return true when the declaration
2836 // context matches, and false when they don't.
2837 //----------------------------------------------------------------------
2838 bool SymbolFileDWARF::DIEDeclContextsMatch(const DWARFDIE &die1,
2839                                            const DWARFDIE &die2) {
2840   if (die1 == die2)
2841     return true;
2842 
2843   DWARFDIECollection decl_ctx_1;
2844   DWARFDIECollection decl_ctx_2;
2845   // The declaration DIE stack is a stack of the declaration context DIEs all
2846   // the way back to the compile unit. If a type "T" is declared inside a class
2847   // "B", and class "B" is declared inside a class "A" and class "A" is in a
2848   // namespace "lldb", and the namespace is in a compile unit, there will be a
2849   // stack of DIEs:
2850   //
2851   //   [0] DW_TAG_class_type for "B"
2852   //   [1] DW_TAG_class_type for "A"
2853   //   [2] DW_TAG_namespace  for "lldb"
2854   //   [3] DW_TAG_compile_unit or DW_TAG_partial_unit for the source file.
2855   //
2856   // We grab both contexts and make sure that everything matches all the way
2857   // back to the compiler unit.
2858 
2859   // First lets grab the decl contexts for both DIEs
2860   die1.GetDeclContextDIEs(decl_ctx_1);
2861   die2.GetDeclContextDIEs(decl_ctx_2);
2862   // Make sure the context arrays have the same size, otherwise we are done
2863   const size_t count1 = decl_ctx_1.Size();
2864   const size_t count2 = decl_ctx_2.Size();
2865   if (count1 != count2)
2866     return false;
2867 
2868   // Make sure the DW_TAG values match all the way back up the compile unit. If
2869   // they don't, then we are done.
2870   DWARFDIE decl_ctx_die1;
2871   DWARFDIE decl_ctx_die2;
2872   size_t i;
2873   for (i = 0; i < count1; i++) {
2874     decl_ctx_die1 = decl_ctx_1.GetDIEAtIndex(i);
2875     decl_ctx_die2 = decl_ctx_2.GetDIEAtIndex(i);
2876     if (decl_ctx_die1.Tag() != decl_ctx_die2.Tag())
2877       return false;
2878   }
2879 #if defined LLDB_CONFIGURATION_DEBUG
2880 
2881   // Make sure the top item in the decl context die array is always
2882   // DW_TAG_compile_unit or DW_TAG_partial_unit. If it isn't then
2883   // something went wrong in the DWARFDIE::GetDeclContextDIEs()
2884   // function.
2885   dw_tag_t cu_tag = decl_ctx_1.GetDIEAtIndex(count1 - 1).Tag();
2886   UNUSED_IF_ASSERT_DISABLED(cu_tag);
2887   assert(cu_tag == DW_TAG_compile_unit || cu_tag == DW_TAG_partial_unit);
2888 
2889 #endif
2890   // Always skip the compile unit when comparing by only iterating up to "count
2891   // - 1". Here we compare the names as we go.
2892   for (i = 0; i < count1 - 1; i++) {
2893     decl_ctx_die1 = decl_ctx_1.GetDIEAtIndex(i);
2894     decl_ctx_die2 = decl_ctx_2.GetDIEAtIndex(i);
2895     const char *name1 = decl_ctx_die1.GetName();
2896     const char *name2 = decl_ctx_die2.GetName();
2897     // If the string was from a DW_FORM_strp, then the pointer will often be
2898     // the same!
2899     if (name1 == name2)
2900       continue;
2901 
2902     // Name pointers are not equal, so only compare the strings if both are not
2903     // NULL.
2904     if (name1 && name2) {
2905       // If the strings don't compare, we are done...
2906       if (strcmp(name1, name2) != 0)
2907         return false;
2908     } else {
2909       // One name was NULL while the other wasn't
2910       return false;
2911     }
2912   }
2913   // We made it through all of the checks and the declaration contexts are
2914   // equal.
2915   return true;
2916 }
2917 
2918 TypeSP SymbolFileDWARF::FindDefinitionTypeForDWARFDeclContext(
2919     const DWARFDeclContext &dwarf_decl_ctx) {
2920   TypeSP type_sp;
2921 
2922   const uint32_t dwarf_decl_ctx_count = dwarf_decl_ctx.GetSize();
2923   if (dwarf_decl_ctx_count > 0) {
2924     const ConstString type_name(dwarf_decl_ctx[0].name);
2925     const dw_tag_t tag = dwarf_decl_ctx[0].tag;
2926 
2927     if (type_name) {
2928       Log *log(LogChannelDWARF::GetLogIfAny(DWARF_LOG_TYPE_COMPLETION |
2929                                             DWARF_LOG_LOOKUPS));
2930       if (log) {
2931         GetObjectFile()->GetModule()->LogMessage(
2932             log, "SymbolFileDWARF::FindDefinitionTypeForDWARFDeclContext(tag=%"
2933                  "s, qualified-name='%s')",
2934             DW_TAG_value_to_name(dwarf_decl_ctx[0].tag),
2935             dwarf_decl_ctx.GetQualifiedName());
2936       }
2937 
2938       DIEArray die_offsets;
2939       m_index->GetTypes(dwarf_decl_ctx, die_offsets);
2940       const size_t num_matches = die_offsets.size();
2941 
2942       // Get the type system that we are looking to find a type for. We will
2943       // use this to ensure any matches we find are in a language that this
2944       // type system supports
2945       const LanguageType language = dwarf_decl_ctx.GetLanguage();
2946       TypeSystem *type_system = (language == eLanguageTypeUnknown)
2947                                     ? nullptr
2948                                     : GetTypeSystemForLanguage(language);
2949 
2950       if (num_matches) {
2951         for (size_t i = 0; i < num_matches; ++i) {
2952           const DIERef &die_ref = die_offsets[i];
2953           DWARFDIE type_die = GetDIE(die_ref);
2954 
2955           if (type_die) {
2956             // Make sure type_die's langauge matches the type system we are
2957             // looking for. We don't want to find a "Foo" type from Java if we
2958             // are looking for a "Foo" type for C, C++, ObjC, or ObjC++.
2959             if (type_system &&
2960                 !type_system->SupportsLanguage(type_die.GetLanguage()))
2961               continue;
2962             bool try_resolving_type = false;
2963 
2964             // Don't try and resolve the DIE we are looking for with the DIE
2965             // itself!
2966             const dw_tag_t type_tag = type_die.Tag();
2967             // Make sure the tags match
2968             if (type_tag == tag) {
2969               // The tags match, lets try resolving this type
2970               try_resolving_type = true;
2971             } else {
2972               // The tags don't match, but we need to watch our for a forward
2973               // declaration for a struct and ("struct foo") ends up being a
2974               // class ("class foo { ... };") or vice versa.
2975               switch (type_tag) {
2976               case DW_TAG_class_type:
2977                 // We had a "class foo", see if we ended up with a "struct foo
2978                 // { ... };"
2979                 try_resolving_type = (tag == DW_TAG_structure_type);
2980                 break;
2981               case DW_TAG_structure_type:
2982                 // We had a "struct foo", see if we ended up with a "class foo
2983                 // { ... };"
2984                 try_resolving_type = (tag == DW_TAG_class_type);
2985                 break;
2986               default:
2987                 // Tags don't match, don't event try to resolve using this type
2988                 // whose name matches....
2989                 break;
2990               }
2991             }
2992 
2993             if (try_resolving_type) {
2994               DWARFDeclContext type_dwarf_decl_ctx;
2995               type_die.GetDWARFDeclContext(type_dwarf_decl_ctx);
2996 
2997               if (log) {
2998                 GetObjectFile()->GetModule()->LogMessage(
2999                     log, "SymbolFileDWARF::"
3000                          "FindDefinitionTypeForDWARFDeclContext(tag=%s, "
3001                          "qualified-name='%s') trying die=0x%8.8x (%s)",
3002                     DW_TAG_value_to_name(dwarf_decl_ctx[0].tag),
3003                     dwarf_decl_ctx.GetQualifiedName(), type_die.GetOffset(),
3004                     type_dwarf_decl_ctx.GetQualifiedName());
3005               }
3006 
3007               // Make sure the decl contexts match all the way up
3008               if (dwarf_decl_ctx == type_dwarf_decl_ctx) {
3009                 Type *resolved_type = ResolveType(type_die, false);
3010                 if (resolved_type && resolved_type != DIE_IS_BEING_PARSED) {
3011                   type_sp = resolved_type->shared_from_this();
3012                   break;
3013                 }
3014               }
3015             } else {
3016               if (log) {
3017                 std::string qualified_name;
3018                 type_die.GetQualifiedName(qualified_name);
3019                 GetObjectFile()->GetModule()->LogMessage(
3020                     log, "SymbolFileDWARF::"
3021                          "FindDefinitionTypeForDWARFDeclContext(tag=%s, "
3022                          "qualified-name='%s') ignoring die=0x%8.8x (%s)",
3023                     DW_TAG_value_to_name(dwarf_decl_ctx[0].tag),
3024                     dwarf_decl_ctx.GetQualifiedName(), type_die.GetOffset(),
3025                     qualified_name.c_str());
3026               }
3027             }
3028           } else {
3029             m_index->ReportInvalidDIEOffset(die_ref.die_offset,
3030                                             type_name.GetStringRef());
3031           }
3032         }
3033       }
3034     }
3035   }
3036   return type_sp;
3037 }
3038 
3039 TypeSP SymbolFileDWARF::ParseType(const SymbolContext &sc, const DWARFDIE &die,
3040                                   bool *type_is_new_ptr) {
3041   TypeSP type_sp;
3042 
3043   if (die) {
3044     TypeSystem *type_system =
3045         GetTypeSystemForLanguage(die.GetCU()->GetLanguageType());
3046 
3047     if (type_system) {
3048       DWARFASTParser *dwarf_ast = type_system->GetDWARFParser();
3049       if (dwarf_ast) {
3050         Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO);
3051         type_sp = dwarf_ast->ParseTypeFromDWARF(sc, die, log, type_is_new_ptr);
3052         if (type_sp) {
3053           TypeList *type_list = GetTypeList();
3054           if (type_list)
3055             type_list->Insert(type_sp);
3056 
3057           if (die.Tag() == DW_TAG_subprogram) {
3058             DIERef die_ref = die.GetDIERef();
3059             std::string scope_qualified_name(GetDeclContextForUID(die.GetID())
3060                                                  .GetScopeQualifiedName()
3061                                                  .AsCString(""));
3062             if (scope_qualified_name.size()) {
3063               NameToOffsetMap::iterator iter =
3064                   m_function_scope_qualified_name_map.find(
3065                       scope_qualified_name);
3066               if (iter != m_function_scope_qualified_name_map.end())
3067                 (*iter).second->insert(die_ref);
3068               else {
3069                 DIERefSetSP new_set(new std::set<DIERef>);
3070                 new_set->insert(die_ref);
3071                 m_function_scope_qualified_name_map.emplace(
3072                     std::make_pair(scope_qualified_name, new_set));
3073               }
3074             }
3075           }
3076         }
3077       }
3078     }
3079   }
3080 
3081   return type_sp;
3082 }
3083 
3084 size_t SymbolFileDWARF::ParseTypes(const SymbolContext &sc,
3085                                    const DWARFDIE &orig_die,
3086                                    bool parse_siblings, bool parse_children) {
3087   size_t types_added = 0;
3088   DWARFDIE die = orig_die;
3089   while (die) {
3090     bool type_is_new = false;
3091     if (ParseType(sc, die, &type_is_new).get()) {
3092       if (type_is_new)
3093         ++types_added;
3094     }
3095 
3096     if (parse_children && die.HasChildren()) {
3097       if (die.Tag() == DW_TAG_subprogram) {
3098         SymbolContext child_sc(sc);
3099         child_sc.function = sc.comp_unit->FindFunctionByUID(die.GetID()).get();
3100         types_added += ParseTypes(child_sc, die.GetFirstChild(), true, true);
3101       } else
3102         types_added += ParseTypes(sc, die.GetFirstChild(), true, true);
3103     }
3104 
3105     if (parse_siblings)
3106       die = die.GetSibling();
3107     else
3108       die.Clear();
3109   }
3110   return types_added;
3111 }
3112 
3113 size_t SymbolFileDWARF::ParseFunctionBlocks(const SymbolContext &sc) {
3114   ASSERT_MODULE_LOCK(this);
3115   assert(sc.comp_unit && sc.function);
3116   size_t functions_added = 0;
3117   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
3118   if (dwarf_cu) {
3119     const dw_offset_t function_die_offset = sc.function->GetID();
3120     DWARFDIE function_die = dwarf_cu->GetDIE(function_die_offset);
3121     if (function_die) {
3122       ParseFunctionBlocks(sc, &sc.function->GetBlock(false), function_die,
3123                           LLDB_INVALID_ADDRESS, 0);
3124     }
3125   }
3126 
3127   return functions_added;
3128 }
3129 
3130 size_t SymbolFileDWARF::ParseTypes(const SymbolContext &sc) {
3131   ASSERT_MODULE_LOCK(this);
3132   // At least a compile unit must be valid
3133   assert(sc.comp_unit);
3134   size_t types_added = 0;
3135   DWARFUnit *dwarf_cu = GetDWARFCompileUnit(sc.comp_unit);
3136   if (dwarf_cu) {
3137     if (sc.function) {
3138       dw_offset_t function_die_offset = sc.function->GetID();
3139       DWARFDIE func_die = dwarf_cu->GetDIE(function_die_offset);
3140       if (func_die && func_die.HasChildren()) {
3141         types_added = ParseTypes(sc, func_die.GetFirstChild(), true, true);
3142       }
3143     } else {
3144       DWARFDIE dwarf_cu_die = dwarf_cu->DIE();
3145       if (dwarf_cu_die && dwarf_cu_die.HasChildren()) {
3146         types_added = ParseTypes(sc, dwarf_cu_die.GetFirstChild(), true, true);
3147       }
3148     }
3149   }
3150 
3151   return types_added;
3152 }
3153 
3154 size_t SymbolFileDWARF::ParseVariablesForContext(const SymbolContext &sc) {
3155   ASSERT_MODULE_LOCK(this);
3156   if (sc.comp_unit != NULL) {
3157     DWARFDebugInfo *info = DebugInfo();
3158     if (info == NULL)
3159       return 0;
3160 
3161     if (sc.function) {
3162       DWARFDIE function_die = info->GetDIE(DIERef(sc.function->GetID(), this));
3163 
3164       const dw_addr_t func_lo_pc = function_die.GetAttributeValueAsAddress(
3165           DW_AT_low_pc, LLDB_INVALID_ADDRESS);
3166       if (func_lo_pc != LLDB_INVALID_ADDRESS) {
3167         const size_t num_variables = ParseVariables(
3168             sc, function_die.GetFirstChild(), func_lo_pc, true, true);
3169 
3170         // Let all blocks know they have parse all their variables
3171         sc.function->GetBlock(false).SetDidParseVariables(true, true);
3172         return num_variables;
3173       }
3174     } else if (sc.comp_unit) {
3175       DWARFUnit *dwarf_cu = info->GetCompileUnit(sc.comp_unit->GetID());
3176 
3177       if (dwarf_cu == NULL)
3178         return 0;
3179 
3180       uint32_t vars_added = 0;
3181       VariableListSP variables(sc.comp_unit->GetVariableList(false));
3182 
3183       if (variables.get() == NULL) {
3184         variables.reset(new VariableList());
3185         sc.comp_unit->SetVariableList(variables);
3186 
3187         DIEArray die_offsets;
3188         m_index->GetGlobalVariables(*dwarf_cu, die_offsets);
3189         const size_t num_matches = die_offsets.size();
3190         if (num_matches) {
3191           for (size_t i = 0; i < num_matches; ++i) {
3192             const DIERef &die_ref = die_offsets[i];
3193             DWARFDIE die = GetDIE(die_ref);
3194             if (die) {
3195               VariableSP var_sp(
3196                   ParseVariableDIE(sc, die, LLDB_INVALID_ADDRESS));
3197               if (var_sp) {
3198                 variables->AddVariableIfUnique(var_sp);
3199                 ++vars_added;
3200               }
3201             } else
3202               m_index->ReportInvalidDIEOffset(die_ref.die_offset, "");
3203           }
3204         }
3205       }
3206       return vars_added;
3207     }
3208   }
3209   return 0;
3210 }
3211 
3212 VariableSP SymbolFileDWARF::ParseVariableDIE(const SymbolContext &sc,
3213                                              const DWARFDIE &die,
3214                                              const lldb::addr_t func_low_pc) {
3215   if (die.GetDWARF() != this)
3216     return die.GetDWARF()->ParseVariableDIE(sc, die, func_low_pc);
3217 
3218   VariableSP var_sp;
3219   if (!die)
3220     return var_sp;
3221 
3222   var_sp = GetDIEToVariable()[die.GetDIE()];
3223   if (var_sp)
3224     return var_sp; // Already been parsed!
3225 
3226   const dw_tag_t tag = die.Tag();
3227   ModuleSP module = GetObjectFile()->GetModule();
3228 
3229   if ((tag == DW_TAG_variable) || (tag == DW_TAG_constant) ||
3230       (tag == DW_TAG_formal_parameter && sc.function)) {
3231     DWARFAttributes attributes;
3232     const size_t num_attributes = die.GetAttributes(attributes);
3233     DWARFDIE spec_die;
3234     if (num_attributes > 0) {
3235       const char *name = NULL;
3236       const char *mangled = NULL;
3237       Declaration decl;
3238       uint32_t i;
3239       DWARFFormValue type_die_form;
3240       DWARFExpression location(die.GetCU());
3241       bool is_external = false;
3242       bool is_artificial = false;
3243       bool location_is_const_value_data = false;
3244       bool has_explicit_location = false;
3245       DWARFFormValue const_value;
3246       Variable::RangeList scope_ranges;
3247       // AccessType accessibility = eAccessNone;
3248 
3249       for (i = 0; i < num_attributes; ++i) {
3250         dw_attr_t attr = attributes.AttributeAtIndex(i);
3251         DWARFFormValue form_value;
3252 
3253         if (attributes.ExtractFormValueAtIndex(i, form_value)) {
3254           switch (attr) {
3255           case DW_AT_decl_file:
3256             decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
3257                 form_value.Unsigned()));
3258             break;
3259           case DW_AT_decl_line:
3260             decl.SetLine(form_value.Unsigned());
3261             break;
3262           case DW_AT_decl_column:
3263             decl.SetColumn(form_value.Unsigned());
3264             break;
3265           case DW_AT_name:
3266             name = form_value.AsCString();
3267             break;
3268           case DW_AT_linkage_name:
3269           case DW_AT_MIPS_linkage_name:
3270             mangled = form_value.AsCString();
3271             break;
3272           case DW_AT_type:
3273             type_die_form = form_value;
3274             break;
3275           case DW_AT_external:
3276             is_external = form_value.Boolean();
3277             break;
3278           case DW_AT_const_value:
3279             // If we have already found a DW_AT_location attribute, ignore this
3280             // attribute.
3281             if (!has_explicit_location) {
3282               location_is_const_value_data = true;
3283               // The constant value will be either a block, a data value or a
3284               // string.
3285               auto debug_info_data = die.GetData();
3286               if (DWARFFormValue::IsBlockForm(form_value.Form())) {
3287                 // Retrieve the value as a block expression.
3288                 uint32_t block_offset =
3289                     form_value.BlockData() - debug_info_data.GetDataStart();
3290                 uint32_t block_length = form_value.Unsigned();
3291                 location.CopyOpcodeData(module, debug_info_data, block_offset,
3292                                         block_length);
3293               } else if (DWARFFormValue::IsDataForm(form_value.Form())) {
3294                 // Retrieve the value as a data expression.
3295                 DWARFFormValue::FixedFormSizes fixed_form_sizes =
3296                     DWARFFormValue::GetFixedFormSizesForAddressSize(
3297                         attributes.CompileUnitAtIndex(i)->GetAddressByteSize(),
3298                         attributes.CompileUnitAtIndex(i)->IsDWARF64());
3299                 uint32_t data_offset = attributes.DIEOffsetAtIndex(i);
3300                 uint32_t data_length =
3301                     fixed_form_sizes.GetSize(form_value.Form());
3302                 if (data_length == 0) {
3303                   const uint8_t *data_pointer = form_value.BlockData();
3304                   if (data_pointer) {
3305                     form_value.Unsigned();
3306                   } else if (DWARFFormValue::IsDataForm(form_value.Form())) {
3307                     // we need to get the byte size of the type later after we
3308                     // create the variable
3309                     const_value = form_value;
3310                   }
3311                 } else
3312                   location.CopyOpcodeData(module, debug_info_data, data_offset,
3313                                           data_length);
3314               } else {
3315                 // Retrieve the value as a string expression.
3316                 if (form_value.Form() == DW_FORM_strp) {
3317                   DWARFFormValue::FixedFormSizes fixed_form_sizes =
3318                       DWARFFormValue::GetFixedFormSizesForAddressSize(
3319                           attributes.CompileUnitAtIndex(i)
3320                               ->GetAddressByteSize(),
3321                           attributes.CompileUnitAtIndex(i)->IsDWARF64());
3322                   uint32_t data_offset = attributes.DIEOffsetAtIndex(i);
3323                   uint32_t data_length =
3324                       fixed_form_sizes.GetSize(form_value.Form());
3325                   location.CopyOpcodeData(module, debug_info_data, data_offset,
3326                                           data_length);
3327                 } else {
3328                   const char *str = form_value.AsCString();
3329                   uint32_t string_offset =
3330                       str - (const char *)debug_info_data.GetDataStart();
3331                   uint32_t string_length = strlen(str) + 1;
3332                   location.CopyOpcodeData(module, debug_info_data,
3333                                           string_offset, string_length);
3334                 }
3335               }
3336             }
3337             break;
3338           case DW_AT_location: {
3339             location_is_const_value_data = false;
3340             has_explicit_location = true;
3341             if (DWARFFormValue::IsBlockForm(form_value.Form())) {
3342               auto data = die.GetData();
3343 
3344               uint32_t block_offset =
3345                   form_value.BlockData() - data.GetDataStart();
3346               uint32_t block_length = form_value.Unsigned();
3347               location.CopyOpcodeData(module, data, block_offset, block_length);
3348             } else {
3349               const DWARFDataExtractor &debug_loc_data = get_debug_loc_data();
3350               const dw_offset_t debug_loc_offset = form_value.Unsigned();
3351 
3352               size_t loc_list_length = DWARFExpression::LocationListSize(
3353                   die.GetCU(), debug_loc_data, debug_loc_offset);
3354               if (loc_list_length > 0) {
3355                 location.CopyOpcodeData(module, debug_loc_data,
3356                                         debug_loc_offset, loc_list_length);
3357                 assert(func_low_pc != LLDB_INVALID_ADDRESS);
3358                 location.SetLocationListSlide(
3359                     func_low_pc -
3360                     attributes.CompileUnitAtIndex(i)->GetBaseAddress());
3361               }
3362             }
3363           } break;
3364           case DW_AT_specification:
3365             spec_die = GetDIE(DIERef(form_value));
3366             break;
3367           case DW_AT_start_scope: {
3368             if (form_value.Form() == DW_FORM_sec_offset) {
3369               DWARFRangeList dwarf_scope_ranges;
3370               const DWARFDebugRanges *debug_ranges = DebugRanges();
3371               debug_ranges->FindRanges(die.GetCU()->GetRangesBase(),
3372                                        form_value.Unsigned(),
3373                                        dwarf_scope_ranges);
3374 
3375               // All DW_AT_start_scope are relative to the base address of the
3376               // compile unit. We add the compile unit base address to make
3377               // sure all the addresses are properly fixed up.
3378               dwarf_scope_ranges.Slide(die.GetCU()->GetBaseAddress());
3379             } else {
3380               // TODO: Handle the case when DW_AT_start_scope have form
3381               // constant. The
3382               // dwarf spec is a bit ambiguous about what is the expected
3383               // behavior in case the enclosing block have a non coninious
3384               // address range and the DW_AT_start_scope entry have a form
3385               // constant.
3386               GetObjectFile()->GetModule()->ReportWarning(
3387                   "0x%8.8" PRIx64
3388                   ": DW_AT_start_scope has unsupported form type (0x%x)\n",
3389                   die.GetID(), form_value.Form());
3390             }
3391 
3392             scope_ranges.Sort();
3393             scope_ranges.CombineConsecutiveRanges();
3394           } break;
3395           case DW_AT_artificial:
3396             is_artificial = form_value.Boolean();
3397             break;
3398           case DW_AT_accessibility:
3399             break; // accessibility =
3400                    // DW_ACCESS_to_AccessType(form_value.Unsigned()); break;
3401           case DW_AT_declaration:
3402           case DW_AT_description:
3403           case DW_AT_endianity:
3404           case DW_AT_segment:
3405           case DW_AT_visibility:
3406           default:
3407           case DW_AT_abstract_origin:
3408           case DW_AT_sibling:
3409             break;
3410           }
3411         }
3412       }
3413 
3414       const DWARFDIE parent_context_die = GetDeclContextDIEContainingDIE(die);
3415       const dw_tag_t parent_tag = die.GetParent().Tag();
3416       bool is_static_member =
3417           (parent_tag == DW_TAG_compile_unit ||
3418            parent_tag == DW_TAG_partial_unit) &&
3419           (parent_context_die.Tag() == DW_TAG_class_type ||
3420            parent_context_die.Tag() == DW_TAG_structure_type);
3421 
3422       ValueType scope = eValueTypeInvalid;
3423 
3424       const DWARFDIE sc_parent_die = GetParentSymbolContextDIE(die);
3425       SymbolContextScope *symbol_context_scope = NULL;
3426 
3427       bool has_explicit_mangled = mangled != nullptr;
3428       if (!mangled) {
3429         // LLDB relies on the mangled name (DW_TAG_linkage_name or
3430         // DW_AT_MIPS_linkage_name) to generate fully qualified names
3431         // of global variables with commands like "frame var j". For
3432         // example, if j were an int variable holding a value 4 and
3433         // declared in a namespace B which in turn is contained in a
3434         // namespace A, the command "frame var j" returns
3435         //   "(int) A::B::j = 4".
3436         // If the compiler does not emit a linkage name, we should be
3437         // able to generate a fully qualified name from the
3438         // declaration context.
3439         if ((parent_tag == DW_TAG_compile_unit ||
3440              parent_tag == DW_TAG_partial_unit) &&
3441             Language::LanguageIsCPlusPlus(die.GetLanguage())) {
3442           DWARFDeclContext decl_ctx;
3443 
3444           die.GetDWARFDeclContext(decl_ctx);
3445           mangled = decl_ctx.GetQualifiedNameAsConstString().GetCString();
3446         }
3447       }
3448 
3449       if (tag == DW_TAG_formal_parameter)
3450         scope = eValueTypeVariableArgument;
3451       else {
3452         // DWARF doesn't specify if a DW_TAG_variable is a local, global
3453         // or static variable, so we have to do a little digging:
3454         // 1) DW_AT_linkage_name implies static lifetime (but may be missing)
3455         // 2) An empty DW_AT_location is an (optimized-out) static lifetime var.
3456         // 3) DW_AT_location containing a DW_OP_addr implies static lifetime.
3457         // Clang likes to combine small global variables into the same symbol
3458         // with locations like: DW_OP_addr(0x1000), DW_OP_constu(2), DW_OP_plus
3459         // so we need to look through the whole expression.
3460         bool is_static_lifetime =
3461             has_explicit_mangled ||
3462             (has_explicit_location && !location.IsValid());
3463         // Check if the location has a DW_OP_addr with any address value...
3464         lldb::addr_t location_DW_OP_addr = LLDB_INVALID_ADDRESS;
3465         if (!location_is_const_value_data) {
3466           bool op_error = false;
3467           location_DW_OP_addr = location.GetLocation_DW_OP_addr(0, op_error);
3468           if (op_error) {
3469             StreamString strm;
3470             location.DumpLocationForAddress(&strm, eDescriptionLevelFull, 0, 0,
3471                                             NULL);
3472             GetObjectFile()->GetModule()->ReportError(
3473                 "0x%8.8x: %s has an invalid location: %s", die.GetOffset(),
3474                 die.GetTagAsCString(), strm.GetData());
3475           }
3476           if (location_DW_OP_addr != LLDB_INVALID_ADDRESS)
3477             is_static_lifetime = true;
3478         }
3479         SymbolFileDWARFDebugMap *debug_map_symfile = GetDebugMapSymfile();
3480         if (debug_map_symfile)
3481           // Set the module of the expression to the linked module
3482           // instead of the oject file so the relocated address can be
3483           // found there.
3484           location.SetModule(debug_map_symfile->GetObjectFile()->GetModule());
3485 
3486         if (is_static_lifetime) {
3487           if (is_external)
3488             scope = eValueTypeVariableGlobal;
3489           else
3490             scope = eValueTypeVariableStatic;
3491 
3492           if (debug_map_symfile) {
3493             // When leaving the DWARF in the .o files on darwin, when we have a
3494             // global variable that wasn't initialized, the .o file might not
3495             // have allocated a virtual address for the global variable. In
3496             // this case it will have created a symbol for the global variable
3497             // that is undefined/data and external and the value will be the
3498             // byte size of the variable. When we do the address map in
3499             // SymbolFileDWARFDebugMap we rely on having an address, we need to
3500             // do some magic here so we can get the correct address for our
3501             // global variable. The address for all of these entries will be
3502             // zero, and there will be an undefined symbol in this object file,
3503             // and the executable will have a matching symbol with a good
3504             // address. So here we dig up the correct address and replace it in
3505             // the location for the variable, and set the variable's symbol
3506             // context scope to be that of the main executable so the file
3507             // address will resolve correctly.
3508             bool linked_oso_file_addr = false;
3509             if (is_external && location_DW_OP_addr == 0) {
3510               // we have a possible uninitialized extern global
3511               ConstString const_name(mangled ? mangled : name);
3512               ObjectFile *debug_map_objfile =
3513                   debug_map_symfile->GetObjectFile();
3514               if (debug_map_objfile) {
3515                 Symtab *debug_map_symtab = debug_map_objfile->GetSymtab();
3516                 if (debug_map_symtab) {
3517                   Symbol *exe_symbol =
3518                       debug_map_symtab->FindFirstSymbolWithNameAndType(
3519                           const_name, eSymbolTypeData, Symtab::eDebugYes,
3520                           Symtab::eVisibilityExtern);
3521                   if (exe_symbol) {
3522                     if (exe_symbol->ValueIsAddress()) {
3523                       const addr_t exe_file_addr =
3524                           exe_symbol->GetAddressRef().GetFileAddress();
3525                       if (exe_file_addr != LLDB_INVALID_ADDRESS) {
3526                         if (location.Update_DW_OP_addr(exe_file_addr)) {
3527                           linked_oso_file_addr = true;
3528                           symbol_context_scope = exe_symbol;
3529                         }
3530                       }
3531                     }
3532                   }
3533                 }
3534               }
3535             }
3536 
3537             if (!linked_oso_file_addr) {
3538               // The DW_OP_addr is not zero, but it contains a .o file address
3539               // which needs to be linked up correctly.
3540               const lldb::addr_t exe_file_addr =
3541                   debug_map_symfile->LinkOSOFileAddress(this,
3542                                                         location_DW_OP_addr);
3543               if (exe_file_addr != LLDB_INVALID_ADDRESS) {
3544                 // Update the file address for this variable
3545                 location.Update_DW_OP_addr(exe_file_addr);
3546               } else {
3547                 // Variable didn't make it into the final executable
3548                 return var_sp;
3549               }
3550             }
3551           }
3552         } else {
3553           if (location_is_const_value_data)
3554             scope = eValueTypeVariableStatic;
3555           else {
3556             scope = eValueTypeVariableLocal;
3557             if (debug_map_symfile) {
3558               // We need to check for TLS addresses that we need to fixup
3559               if (location.ContainsThreadLocalStorage()) {
3560                 location.LinkThreadLocalStorage(
3561                     debug_map_symfile->GetObjectFile()->GetModule(),
3562                     [this, debug_map_symfile](
3563                         lldb::addr_t unlinked_file_addr) -> lldb::addr_t {
3564                       return debug_map_symfile->LinkOSOFileAddress(
3565                           this, unlinked_file_addr);
3566                     });
3567                 scope = eValueTypeVariableThreadLocal;
3568               }
3569             }
3570           }
3571         }
3572       }
3573 
3574       if (symbol_context_scope == NULL) {
3575         switch (parent_tag) {
3576         case DW_TAG_subprogram:
3577         case DW_TAG_inlined_subroutine:
3578         case DW_TAG_lexical_block:
3579           if (sc.function) {
3580             symbol_context_scope = sc.function->GetBlock(true).FindBlockByID(
3581                 sc_parent_die.GetID());
3582             if (symbol_context_scope == NULL)
3583               symbol_context_scope = sc.function;
3584           }
3585           break;
3586 
3587         default:
3588           symbol_context_scope = sc.comp_unit;
3589           break;
3590         }
3591       }
3592 
3593       if (symbol_context_scope) {
3594         SymbolFileTypeSP type_sp(
3595             new SymbolFileType(*this, DIERef(type_die_form).GetUID(this)));
3596 
3597         if (const_value.Form() && type_sp && type_sp->GetType())
3598           location.CopyOpcodeData(const_value.Unsigned(),
3599                                   type_sp->GetType()->GetByteSize(),
3600                                   die.GetCU()->GetAddressByteSize());
3601 
3602         var_sp.reset(new Variable(die.GetID(), name, mangled, type_sp, scope,
3603                                   symbol_context_scope, scope_ranges, &decl,
3604                                   location, is_external, is_artificial,
3605                                   is_static_member));
3606 
3607         var_sp->SetLocationIsConstantValueData(location_is_const_value_data);
3608       } else {
3609         // Not ready to parse this variable yet. It might be a global or static
3610         // variable that is in a function scope and the function in the symbol
3611         // context wasn't filled in yet
3612         return var_sp;
3613       }
3614     }
3615     // Cache var_sp even if NULL (the variable was just a specification or was
3616     // missing vital information to be able to be displayed in the debugger
3617     // (missing location due to optimization, etc)) so we don't re-parse this
3618     // DIE over and over later...
3619     GetDIEToVariable()[die.GetDIE()] = var_sp;
3620     if (spec_die)
3621       GetDIEToVariable()[spec_die.GetDIE()] = var_sp;
3622   }
3623   return var_sp;
3624 }
3625 
3626 DWARFDIE
3627 SymbolFileDWARF::FindBlockContainingSpecification(
3628     const DIERef &func_die_ref, dw_offset_t spec_block_die_offset) {
3629   // Give the concrete function die specified by "func_die_offset", find the
3630   // concrete block whose DW_AT_specification or DW_AT_abstract_origin points
3631   // to "spec_block_die_offset"
3632   return FindBlockContainingSpecification(DebugInfo()->GetDIE(func_die_ref),
3633                                           spec_block_die_offset);
3634 }
3635 
3636 DWARFDIE
3637 SymbolFileDWARF::FindBlockContainingSpecification(
3638     const DWARFDIE &die, dw_offset_t spec_block_die_offset) {
3639   if (die) {
3640     switch (die.Tag()) {
3641     case DW_TAG_subprogram:
3642     case DW_TAG_inlined_subroutine:
3643     case DW_TAG_lexical_block: {
3644       if (die.GetAttributeValueAsReference(
3645               DW_AT_specification, DW_INVALID_OFFSET) == spec_block_die_offset)
3646         return die;
3647 
3648       if (die.GetAttributeValueAsReference(DW_AT_abstract_origin,
3649                                            DW_INVALID_OFFSET) ==
3650           spec_block_die_offset)
3651         return die;
3652     } break;
3653     }
3654 
3655     // Give the concrete function die specified by "func_die_offset", find the
3656     // concrete block whose DW_AT_specification or DW_AT_abstract_origin points
3657     // to "spec_block_die_offset"
3658     for (DWARFDIE child_die = die.GetFirstChild(); child_die;
3659          child_die = child_die.GetSibling()) {
3660       DWARFDIE result_die =
3661           FindBlockContainingSpecification(child_die, spec_block_die_offset);
3662       if (result_die)
3663         return result_die;
3664     }
3665   }
3666 
3667   return DWARFDIE();
3668 }
3669 
3670 size_t SymbolFileDWARF::ParseVariables(const SymbolContext &sc,
3671                                        const DWARFDIE &orig_die,
3672                                        const lldb::addr_t func_low_pc,
3673                                        bool parse_siblings, bool parse_children,
3674                                        VariableList *cc_variable_list) {
3675   if (!orig_die)
3676     return 0;
3677 
3678   VariableListSP variable_list_sp;
3679 
3680   size_t vars_added = 0;
3681   DWARFDIE die = orig_die;
3682   while (die) {
3683     dw_tag_t tag = die.Tag();
3684 
3685     // Check to see if we have already parsed this variable or constant?
3686     VariableSP var_sp = GetDIEToVariable()[die.GetDIE()];
3687     if (var_sp) {
3688       if (cc_variable_list)
3689         cc_variable_list->AddVariableIfUnique(var_sp);
3690     } else {
3691       // We haven't already parsed it, lets do that now.
3692       if ((tag == DW_TAG_variable) || (tag == DW_TAG_constant) ||
3693           (tag == DW_TAG_formal_parameter && sc.function)) {
3694         if (variable_list_sp.get() == NULL) {
3695           DWARFDIE sc_parent_die = GetParentSymbolContextDIE(orig_die);
3696           dw_tag_t parent_tag = sc_parent_die.Tag();
3697           switch (parent_tag) {
3698           case DW_TAG_compile_unit:
3699           case DW_TAG_partial_unit:
3700             if (sc.comp_unit != NULL) {
3701               variable_list_sp = sc.comp_unit->GetVariableList(false);
3702               if (variable_list_sp.get() == NULL) {
3703                 variable_list_sp.reset(new VariableList());
3704               }
3705             } else {
3706               GetObjectFile()->GetModule()->ReportError(
3707                   "parent 0x%8.8" PRIx64 " %s with no valid compile unit in "
3708                                          "symbol context for 0x%8.8" PRIx64
3709                   " %s.\n",
3710                   sc_parent_die.GetID(), sc_parent_die.GetTagAsCString(),
3711                   orig_die.GetID(), orig_die.GetTagAsCString());
3712             }
3713             break;
3714 
3715           case DW_TAG_subprogram:
3716           case DW_TAG_inlined_subroutine:
3717           case DW_TAG_lexical_block:
3718             if (sc.function != NULL) {
3719               // Check to see if we already have parsed the variables for the
3720               // given scope
3721 
3722               Block *block = sc.function->GetBlock(true).FindBlockByID(
3723                   sc_parent_die.GetID());
3724               if (block == NULL) {
3725                 // This must be a specification or abstract origin with a
3726                 // concrete block counterpart in the current function. We need
3727                 // to find the concrete block so we can correctly add the
3728                 // variable to it
3729                 const DWARFDIE concrete_block_die =
3730                     FindBlockContainingSpecification(
3731                         DIERef(sc.function->GetID(), this),
3732                         sc_parent_die.GetOffset());
3733                 if (concrete_block_die)
3734                   block = sc.function->GetBlock(true).FindBlockByID(
3735                       concrete_block_die.GetID());
3736               }
3737 
3738               if (block != NULL) {
3739                 const bool can_create = false;
3740                 variable_list_sp = block->GetBlockVariableList(can_create);
3741                 if (variable_list_sp.get() == NULL) {
3742                   variable_list_sp.reset(new VariableList());
3743                   block->SetVariableList(variable_list_sp);
3744                 }
3745               }
3746             }
3747             break;
3748 
3749           default:
3750             GetObjectFile()->GetModule()->ReportError(
3751                 "didn't find appropriate parent DIE for variable list for "
3752                 "0x%8.8" PRIx64 " %s.\n",
3753                 orig_die.GetID(), orig_die.GetTagAsCString());
3754             break;
3755           }
3756         }
3757 
3758         if (variable_list_sp) {
3759           VariableSP var_sp(ParseVariableDIE(sc, die, func_low_pc));
3760           if (var_sp) {
3761             variable_list_sp->AddVariableIfUnique(var_sp);
3762             if (cc_variable_list)
3763               cc_variable_list->AddVariableIfUnique(var_sp);
3764             ++vars_added;
3765           }
3766         }
3767       }
3768     }
3769 
3770     bool skip_children = (sc.function == NULL && tag == DW_TAG_subprogram);
3771 
3772     if (!skip_children && parse_children && die.HasChildren()) {
3773       vars_added += ParseVariables(sc, die.GetFirstChild(), func_low_pc, true,
3774                                    true, cc_variable_list);
3775     }
3776 
3777     if (parse_siblings)
3778       die = die.GetSibling();
3779     else
3780       die.Clear();
3781   }
3782   return vars_added;
3783 }
3784 
3785 /// Collect call graph edges present in a function DIE.
3786 static std::vector<lldb_private::CallEdge>
3787 CollectCallEdges(DWARFDIE function_die) {
3788   // Check if the function has a supported call site-related attribute.
3789   // TODO: In the future it may be worthwhile to support call_all_source_calls.
3790   uint64_t has_call_edges =
3791       function_die.GetAttributeValueAsUnsigned(DW_AT_call_all_calls, 0);
3792   if (!has_call_edges)
3793     return {};
3794 
3795   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
3796   LLDB_LOG(log, "CollectCallEdges: Found call site info in {0}",
3797            function_die.GetPubname());
3798 
3799   // Scan the DIE for TAG_call_site entries.
3800   // TODO: A recursive scan of all blocks in the subprogram is needed in order
3801   // to be DWARF5-compliant. This may need to be done lazily to be performant.
3802   // For now, assume that all entries are nested directly under the subprogram
3803   // (this is the kind of DWARF LLVM produces) and parse them eagerly.
3804   std::vector<CallEdge> call_edges;
3805   for (DWARFDIE child = function_die.GetFirstChild(); child.IsValid();
3806        child = child.GetSibling()) {
3807     if (child.Tag() != DW_TAG_call_site)
3808       continue;
3809 
3810     // Extract DW_AT_call_origin (the call target's DIE).
3811     DWARFDIE call_origin = child.GetReferencedDIE(DW_AT_call_origin);
3812     if (!call_origin.IsValid()) {
3813       LLDB_LOG(log, "CollectCallEdges: Invalid call origin in {0}",
3814                function_die.GetPubname());
3815       continue;
3816     }
3817 
3818     // Extract DW_AT_call_return_pc (the PC the call returns to) if it's
3819     // available. It should only ever be unavailable for tail call edges, in
3820     // which case use LLDB_INVALID_ADDRESS.
3821     addr_t return_pc = child.GetAttributeValueAsAddress(DW_AT_call_return_pc,
3822                                                         LLDB_INVALID_ADDRESS);
3823 
3824     LLDB_LOG(log, "CollectCallEdges: Found call origin: {0} (retn-PC: {1:x})",
3825              call_origin.GetPubname(), return_pc);
3826     call_edges.emplace_back(call_origin.GetMangledName(), return_pc);
3827   }
3828   return call_edges;
3829 }
3830 
3831 std::vector<lldb_private::CallEdge>
3832 SymbolFileDWARF::ParseCallEdgesInFunction(UserID func_id) {
3833   DWARFDIE func_die = GetDIEFromUID(func_id.GetID());
3834   if (func_die.IsValid())
3835     return CollectCallEdges(func_die);
3836   return {};
3837 }
3838 
3839 //------------------------------------------------------------------
3840 // PluginInterface protocol
3841 //------------------------------------------------------------------
3842 ConstString SymbolFileDWARF::GetPluginName() { return GetPluginNameStatic(); }
3843 
3844 uint32_t SymbolFileDWARF::GetPluginVersion() { return 1; }
3845 
3846 void SymbolFileDWARF::Dump(lldb_private::Stream &s) { m_index->Dump(s); }
3847 
3848 SymbolFileDWARFDebugMap *SymbolFileDWARF::GetDebugMapSymfile() {
3849   if (m_debug_map_symfile == NULL && !m_debug_map_module_wp.expired()) {
3850     lldb::ModuleSP module_sp(m_debug_map_module_wp.lock());
3851     if (module_sp) {
3852       SymbolVendor *sym_vendor = module_sp->GetSymbolVendor();
3853       if (sym_vendor)
3854         m_debug_map_symfile =
3855             (SymbolFileDWARFDebugMap *)sym_vendor->GetSymbolFile();
3856     }
3857   }
3858   return m_debug_map_symfile;
3859 }
3860 
3861 DWARFExpression::LocationListFormat
3862 SymbolFileDWARF::GetLocationListFormat() const {
3863   return DWARFExpression::RegularLocationList;
3864 }
3865 
3866 SymbolFileDWARFDwp *SymbolFileDWARF::GetDwpSymbolFile() {
3867   llvm::call_once(m_dwp_symfile_once_flag, [this]() {
3868     ModuleSpec module_spec;
3869     module_spec.GetFileSpec() = m_obj_file->GetFileSpec();
3870     module_spec.GetSymbolFileSpec() =
3871         FileSpec(m_obj_file->GetFileSpec().GetPath() + ".dwp", false);
3872     FileSpec dwp_filespec = Symbols::LocateExecutableSymbolFile(module_spec);
3873     if (dwp_filespec.Exists()) {
3874       m_dwp_symfile = SymbolFileDWARFDwp::Create(GetObjectFile()->GetModule(),
3875                                                  dwp_filespec);
3876     }
3877   });
3878   return m_dwp_symfile.get();
3879 }
3880