xref: /freebsd-src/contrib/llvm-project/lldb/source/Symbol/ObjectFile.cpp (revision c9ccf3a32da427475985b85d7df023ccfb138c27)
1 //===-- ObjectFile.cpp ----------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/Symbol/ObjectFile.h"
10 #include "lldb/Core/Module.h"
11 #include "lldb/Core/ModuleSpec.h"
12 #include "lldb/Core/PluginManager.h"
13 #include "lldb/Core/Section.h"
14 #include "lldb/Symbol/CallFrameInfo.h"
15 #include "lldb/Symbol/ObjectContainer.h"
16 #include "lldb/Symbol/SymbolFile.h"
17 #include "lldb/Target/Process.h"
18 #include "lldb/Target/SectionLoadList.h"
19 #include "lldb/Target/Target.h"
20 #include "lldb/Utility/DataBuffer.h"
21 #include "lldb/Utility/DataBufferHeap.h"
22 #include "lldb/Utility/Log.h"
23 #include "lldb/Utility/Timer.h"
24 #include "lldb/lldb-private.h"
25 
26 #include "llvm/Support/DJB.h"
27 
28 using namespace lldb;
29 using namespace lldb_private;
30 
31 char ObjectFile::ID;
32 
33 static ObjectFileSP
34 CreateObjectFromContainer(const lldb::ModuleSP &module_sp, const FileSpec *file,
35                           lldb::offset_t file_offset, lldb::offset_t file_size,
36                           DataBufferSP &data_sp, lldb::offset_t &data_offset) {
37   ObjectContainerCreateInstance callback;
38   for (uint32_t idx = 0;
39        (callback = PluginManager::GetObjectContainerCreateCallbackAtIndex(
40             idx)) != nullptr;
41        ++idx) {
42     std::unique_ptr<ObjectContainer> object_container_up(callback(
43         module_sp, data_sp, data_offset, file, file_offset, file_size));
44     if (object_container_up)
45       return object_container_up->GetObjectFile(file);
46   }
47   return {};
48 }
49 
50 ObjectFileSP
51 ObjectFile::FindPlugin(const lldb::ModuleSP &module_sp, const FileSpec *file,
52                        lldb::offset_t file_offset, lldb::offset_t file_size,
53                        DataBufferSP &data_sp, lldb::offset_t &data_offset) {
54   LLDB_SCOPED_TIMERF(
55       "ObjectFile::FindPlugin (module = %s, file = %p, file_offset = "
56       "0x%8.8" PRIx64 ", file_size = 0x%8.8" PRIx64 ")",
57       module_sp->GetFileSpec().GetPath().c_str(),
58       static_cast<const void *>(file), static_cast<uint64_t>(file_offset),
59       static_cast<uint64_t>(file_size));
60 
61   if (!module_sp)
62     return {};
63 
64   if (!file)
65     return {};
66 
67   if (!data_sp) {
68     const bool file_exists = FileSystem::Instance().Exists(*file);
69     // We have an object name which most likely means we have a .o file in
70     // a static archive (.a file). Try and see if we have a cached archive
71     // first without reading any data first
72     if (file_exists && module_sp->GetObjectName()) {
73       ObjectFileSP object_file_sp = CreateObjectFromContainer(
74           module_sp, file, file_offset, file_size, data_sp, data_offset);
75       if (object_file_sp)
76         return object_file_sp;
77     }
78     // Ok, we didn't find any containers that have a named object, now lets
79     // read the first 512 bytes from the file so the object file and object
80     // container plug-ins can use these bytes to see if they can parse this
81     // file.
82     if (file_size > 0) {
83       data_sp = FileSystem::Instance().CreateDataBuffer(file->GetPath(), 512,
84                                                         file_offset);
85       data_offset = 0;
86     }
87   }
88 
89   if (!data_sp || data_sp->GetByteSize() == 0) {
90     // Check for archive file with format "/path/to/archive.a(object.o)"
91     llvm::SmallString<256> path_with_object;
92     module_sp->GetFileSpec().GetPath(path_with_object);
93 
94     FileSpec archive_file;
95     ConstString archive_object;
96     const bool must_exist = true;
97     if (ObjectFile::SplitArchivePathWithObject(path_with_object, archive_file,
98                                                archive_object, must_exist)) {
99       file_size = FileSystem::Instance().GetByteSize(archive_file);
100       if (file_size > 0) {
101         file = &archive_file;
102         module_sp->SetFileSpecAndObjectName(archive_file, archive_object);
103         // Check if this is a object container by iterating through all
104         // object container plugin instances and then trying to get an
105         // object file from the container plugins since we had a name.
106         // Also, don't read
107         // ANY data in case there is data cached in the container plug-ins
108         // (like BSD archives caching the contained objects within an
109         // file).
110         ObjectFileSP object_file_sp = CreateObjectFromContainer(
111             module_sp, file, file_offset, file_size, data_sp, data_offset);
112         if (object_file_sp)
113           return object_file_sp;
114         // We failed to find any cached object files in the container plug-
115         // ins, so lets read the first 512 bytes and try again below...
116         data_sp = FileSystem::Instance().CreateDataBuffer(
117             archive_file.GetPath(), 512, file_offset);
118       }
119     }
120   }
121 
122   if (data_sp && data_sp->GetByteSize() > 0) {
123     // Check if this is a normal object file by iterating through all
124     // object file plugin instances.
125     ObjectFileCreateInstance callback;
126     for (uint32_t idx = 0;
127          (callback = PluginManager::GetObjectFileCreateCallbackAtIndex(idx)) !=
128          nullptr;
129          ++idx) {
130       ObjectFileSP object_file_sp(callback(module_sp, data_sp, data_offset,
131                                            file, file_offset, file_size));
132       if (object_file_sp.get())
133         return object_file_sp;
134     }
135 
136     // Check if this is a object container by iterating through all object
137     // container plugin instances and then trying to get an object file
138     // from the container.
139     ObjectFileSP object_file_sp = CreateObjectFromContainer(
140         module_sp, file, file_offset, file_size, data_sp, data_offset);
141     if (object_file_sp)
142       return object_file_sp;
143   }
144 
145   // We didn't find it, so clear our shared pointer in case it contains
146   // anything and return an empty shared pointer
147   return {};
148 }
149 
150 ObjectFileSP ObjectFile::FindPlugin(const lldb::ModuleSP &module_sp,
151                                     const ProcessSP &process_sp,
152                                     lldb::addr_t header_addr,
153                                     DataBufferSP &data_sp) {
154   ObjectFileSP object_file_sp;
155 
156   if (module_sp) {
157     LLDB_SCOPED_TIMERF("ObjectFile::FindPlugin (module = "
158                        "%s, process = %p, header_addr = "
159                        "0x%" PRIx64 ")",
160                        module_sp->GetFileSpec().GetPath().c_str(),
161                        static_cast<void *>(process_sp.get()), header_addr);
162     uint32_t idx;
163 
164     // Check if this is a normal object file by iterating through all object
165     // file plugin instances.
166     ObjectFileCreateMemoryInstance create_callback;
167     for (idx = 0;
168          (create_callback =
169               PluginManager::GetObjectFileCreateMemoryCallbackAtIndex(idx)) !=
170          nullptr;
171          ++idx) {
172       object_file_sp.reset(
173           create_callback(module_sp, data_sp, process_sp, header_addr));
174       if (object_file_sp.get())
175         return object_file_sp;
176     }
177   }
178 
179   // We didn't find it, so clear our shared pointer in case it contains
180   // anything and return an empty shared pointer
181   object_file_sp.reset();
182   return object_file_sp;
183 }
184 
185 size_t ObjectFile::GetModuleSpecifications(const FileSpec &file,
186                                            lldb::offset_t file_offset,
187                                            lldb::offset_t file_size,
188                                            ModuleSpecList &specs,
189                                            DataBufferSP data_sp) {
190   if (!data_sp)
191     data_sp = FileSystem::Instance().CreateDataBuffer(file.GetPath(), 512,
192                                                       file_offset);
193   if (data_sp) {
194     if (file_size == 0) {
195       const lldb::offset_t actual_file_size =
196           FileSystem::Instance().GetByteSize(file);
197       if (actual_file_size > file_offset)
198         file_size = actual_file_size - file_offset;
199     }
200     return ObjectFile::GetModuleSpecifications(file,        // file spec
201                                                data_sp,     // data bytes
202                                                0,           // data offset
203                                                file_offset, // file offset
204                                                file_size,   // file length
205                                                specs);
206   }
207   return 0;
208 }
209 
210 size_t ObjectFile::GetModuleSpecifications(
211     const lldb_private::FileSpec &file, lldb::DataBufferSP &data_sp,
212     lldb::offset_t data_offset, lldb::offset_t file_offset,
213     lldb::offset_t file_size, lldb_private::ModuleSpecList &specs) {
214   const size_t initial_count = specs.GetSize();
215   ObjectFileGetModuleSpecifications callback;
216   uint32_t i;
217   // Try the ObjectFile plug-ins
218   for (i = 0;
219        (callback =
220             PluginManager::GetObjectFileGetModuleSpecificationsCallbackAtIndex(
221                 i)) != nullptr;
222        ++i) {
223     if (callback(file, data_sp, data_offset, file_offset, file_size, specs) > 0)
224       return specs.GetSize() - initial_count;
225   }
226 
227   // Try the ObjectContainer plug-ins
228   for (i = 0;
229        (callback = PluginManager::
230             GetObjectContainerGetModuleSpecificationsCallbackAtIndex(i)) !=
231        nullptr;
232        ++i) {
233     if (callback(file, data_sp, data_offset, file_offset, file_size, specs) > 0)
234       return specs.GetSize() - initial_count;
235   }
236   return 0;
237 }
238 
239 ObjectFile::ObjectFile(const lldb::ModuleSP &module_sp,
240                        const FileSpec *file_spec_ptr,
241                        lldb::offset_t file_offset, lldb::offset_t length,
242                        const lldb::DataBufferSP &data_sp,
243                        lldb::offset_t data_offset)
244     : ModuleChild(module_sp),
245       m_file(), // This file could be different from the original module's file
246       m_type(eTypeInvalid), m_strata(eStrataInvalid),
247       m_file_offset(file_offset), m_length(length), m_data(), m_process_wp(),
248       m_memory_addr(LLDB_INVALID_ADDRESS), m_sections_up(), m_symtab_up(),
249       m_symtab_once_up(new llvm::once_flag()) {
250   if (file_spec_ptr)
251     m_file = *file_spec_ptr;
252   if (data_sp)
253     m_data.SetData(data_sp, data_offset, length);
254   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT));
255   LLDB_LOGF(log,
256             "%p ObjectFile::ObjectFile() module = %p (%s), file = %s, "
257             "file_offset = 0x%8.8" PRIx64 ", size = %" PRIu64,
258             static_cast<void *>(this), static_cast<void *>(module_sp.get()),
259             module_sp->GetSpecificationDescription().c_str(),
260             m_file ? m_file.GetPath().c_str() : "<NULL>", m_file_offset,
261             m_length);
262 }
263 
264 ObjectFile::ObjectFile(const lldb::ModuleSP &module_sp,
265                        const ProcessSP &process_sp, lldb::addr_t header_addr,
266                        DataBufferSP &header_data_sp)
267     : ModuleChild(module_sp), m_file(), m_type(eTypeInvalid),
268       m_strata(eStrataInvalid), m_file_offset(0), m_length(0), m_data(),
269       m_process_wp(process_sp), m_memory_addr(header_addr), m_sections_up(),
270       m_symtab_up(), m_symtab_once_up(new llvm::once_flag()) {
271   if (header_data_sp)
272     m_data.SetData(header_data_sp, 0, header_data_sp->GetByteSize());
273   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT));
274   LLDB_LOGF(log,
275             "%p ObjectFile::ObjectFile() module = %p (%s), process = %p, "
276             "header_addr = 0x%" PRIx64,
277             static_cast<void *>(this), static_cast<void *>(module_sp.get()),
278             module_sp->GetSpecificationDescription().c_str(),
279             static_cast<void *>(process_sp.get()), m_memory_addr);
280 }
281 
282 ObjectFile::~ObjectFile() {
283   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT));
284   LLDB_LOGF(log, "%p ObjectFile::~ObjectFile ()\n", static_cast<void *>(this));
285 }
286 
287 bool ObjectFile::SetModulesArchitecture(const ArchSpec &new_arch) {
288   ModuleSP module_sp(GetModule());
289   if (module_sp)
290     return module_sp->SetArchitecture(new_arch);
291   return false;
292 }
293 
294 AddressClass ObjectFile::GetAddressClass(addr_t file_addr) {
295   Symtab *symtab = GetSymtab();
296   if (symtab) {
297     Symbol *symbol = symtab->FindSymbolContainingFileAddress(file_addr);
298     if (symbol) {
299       if (symbol->ValueIsAddress()) {
300         const SectionSP section_sp(symbol->GetAddressRef().GetSection());
301         if (section_sp) {
302           const SectionType section_type = section_sp->GetType();
303           switch (section_type) {
304           case eSectionTypeInvalid:
305             return AddressClass::eUnknown;
306           case eSectionTypeCode:
307             return AddressClass::eCode;
308           case eSectionTypeContainer:
309             return AddressClass::eUnknown;
310           case eSectionTypeData:
311           case eSectionTypeDataCString:
312           case eSectionTypeDataCStringPointers:
313           case eSectionTypeDataSymbolAddress:
314           case eSectionTypeData4:
315           case eSectionTypeData8:
316           case eSectionTypeData16:
317           case eSectionTypeDataPointers:
318           case eSectionTypeZeroFill:
319           case eSectionTypeDataObjCMessageRefs:
320           case eSectionTypeDataObjCCFStrings:
321           case eSectionTypeGoSymtab:
322             return AddressClass::eData;
323           case eSectionTypeDebug:
324           case eSectionTypeDWARFDebugAbbrev:
325           case eSectionTypeDWARFDebugAbbrevDwo:
326           case eSectionTypeDWARFDebugAddr:
327           case eSectionTypeDWARFDebugAranges:
328           case eSectionTypeDWARFDebugCuIndex:
329           case eSectionTypeDWARFDebugFrame:
330           case eSectionTypeDWARFDebugInfo:
331           case eSectionTypeDWARFDebugInfoDwo:
332           case eSectionTypeDWARFDebugLine:
333           case eSectionTypeDWARFDebugLineStr:
334           case eSectionTypeDWARFDebugLoc:
335           case eSectionTypeDWARFDebugLocDwo:
336           case eSectionTypeDWARFDebugLocLists:
337           case eSectionTypeDWARFDebugLocListsDwo:
338           case eSectionTypeDWARFDebugMacInfo:
339           case eSectionTypeDWARFDebugMacro:
340           case eSectionTypeDWARFDebugNames:
341           case eSectionTypeDWARFDebugPubNames:
342           case eSectionTypeDWARFDebugPubTypes:
343           case eSectionTypeDWARFDebugRanges:
344           case eSectionTypeDWARFDebugRngLists:
345           case eSectionTypeDWARFDebugRngListsDwo:
346           case eSectionTypeDWARFDebugStr:
347           case eSectionTypeDWARFDebugStrDwo:
348           case eSectionTypeDWARFDebugStrOffsets:
349           case eSectionTypeDWARFDebugStrOffsetsDwo:
350           case eSectionTypeDWARFDebugTuIndex:
351           case eSectionTypeDWARFDebugTypes:
352           case eSectionTypeDWARFDebugTypesDwo:
353           case eSectionTypeDWARFAppleNames:
354           case eSectionTypeDWARFAppleTypes:
355           case eSectionTypeDWARFAppleNamespaces:
356           case eSectionTypeDWARFAppleObjC:
357           case eSectionTypeDWARFGNUDebugAltLink:
358             return AddressClass::eDebug;
359           case eSectionTypeEHFrame:
360           case eSectionTypeARMexidx:
361           case eSectionTypeARMextab:
362           case eSectionTypeCompactUnwind:
363             return AddressClass::eRuntime;
364           case eSectionTypeELFSymbolTable:
365           case eSectionTypeELFDynamicSymbols:
366           case eSectionTypeELFRelocationEntries:
367           case eSectionTypeELFDynamicLinkInfo:
368           case eSectionTypeOther:
369             return AddressClass::eUnknown;
370           case eSectionTypeAbsoluteAddress:
371             // In case of absolute sections decide the address class based on
372             // the symbol type because the section type isn't specify if it is
373             // a code or a data section.
374             break;
375           }
376         }
377       }
378 
379       const SymbolType symbol_type = symbol->GetType();
380       switch (symbol_type) {
381       case eSymbolTypeAny:
382         return AddressClass::eUnknown;
383       case eSymbolTypeAbsolute:
384         return AddressClass::eUnknown;
385       case eSymbolTypeCode:
386         return AddressClass::eCode;
387       case eSymbolTypeTrampoline:
388         return AddressClass::eCode;
389       case eSymbolTypeResolver:
390         return AddressClass::eCode;
391       case eSymbolTypeData:
392         return AddressClass::eData;
393       case eSymbolTypeRuntime:
394         return AddressClass::eRuntime;
395       case eSymbolTypeException:
396         return AddressClass::eRuntime;
397       case eSymbolTypeSourceFile:
398         return AddressClass::eDebug;
399       case eSymbolTypeHeaderFile:
400         return AddressClass::eDebug;
401       case eSymbolTypeObjectFile:
402         return AddressClass::eDebug;
403       case eSymbolTypeCommonBlock:
404         return AddressClass::eDebug;
405       case eSymbolTypeBlock:
406         return AddressClass::eDebug;
407       case eSymbolTypeLocal:
408         return AddressClass::eData;
409       case eSymbolTypeParam:
410         return AddressClass::eData;
411       case eSymbolTypeVariable:
412         return AddressClass::eData;
413       case eSymbolTypeVariableType:
414         return AddressClass::eDebug;
415       case eSymbolTypeLineEntry:
416         return AddressClass::eDebug;
417       case eSymbolTypeLineHeader:
418         return AddressClass::eDebug;
419       case eSymbolTypeScopeBegin:
420         return AddressClass::eDebug;
421       case eSymbolTypeScopeEnd:
422         return AddressClass::eDebug;
423       case eSymbolTypeAdditional:
424         return AddressClass::eUnknown;
425       case eSymbolTypeCompiler:
426         return AddressClass::eDebug;
427       case eSymbolTypeInstrumentation:
428         return AddressClass::eDebug;
429       case eSymbolTypeUndefined:
430         return AddressClass::eUnknown;
431       case eSymbolTypeObjCClass:
432         return AddressClass::eRuntime;
433       case eSymbolTypeObjCMetaClass:
434         return AddressClass::eRuntime;
435       case eSymbolTypeObjCIVar:
436         return AddressClass::eRuntime;
437       case eSymbolTypeReExported:
438         return AddressClass::eRuntime;
439       }
440     }
441   }
442   return AddressClass::eUnknown;
443 }
444 
445 DataBufferSP ObjectFile::ReadMemory(const ProcessSP &process_sp,
446                                     lldb::addr_t addr, size_t byte_size) {
447   DataBufferSP data_sp;
448   if (process_sp) {
449     std::unique_ptr<DataBufferHeap> data_up(new DataBufferHeap(byte_size, 0));
450     Status error;
451     const size_t bytes_read = process_sp->ReadMemory(
452         addr, data_up->GetBytes(), data_up->GetByteSize(), error);
453     if (bytes_read == byte_size)
454       data_sp.reset(data_up.release());
455   }
456   return data_sp;
457 }
458 
459 size_t ObjectFile::GetData(lldb::offset_t offset, size_t length,
460                            DataExtractor &data) const {
461   // The entire file has already been mmap'ed into m_data, so just copy from
462   // there as the back mmap buffer will be shared with shared pointers.
463   return data.SetData(m_data, offset, length);
464 }
465 
466 size_t ObjectFile::CopyData(lldb::offset_t offset, size_t length,
467                             void *dst) const {
468   // The entire file has already been mmap'ed into m_data, so just copy from
469   // there Note that the data remains in target byte order.
470   return m_data.CopyData(offset, length, dst);
471 }
472 
473 size_t ObjectFile::ReadSectionData(Section *section,
474                                    lldb::offset_t section_offset, void *dst,
475                                    size_t dst_len) {
476   assert(section);
477   section_offset *= section->GetTargetByteSize();
478 
479   // If some other objectfile owns this data, pass this to them.
480   if (section->GetObjectFile() != this)
481     return section->GetObjectFile()->ReadSectionData(section, section_offset,
482                                                      dst, dst_len);
483 
484   if (!section->IsRelocated())
485     RelocateSection(section);
486 
487   if (IsInMemory()) {
488     ProcessSP process_sp(m_process_wp.lock());
489     if (process_sp) {
490       Status error;
491       const addr_t base_load_addr =
492           section->GetLoadBaseAddress(&process_sp->GetTarget());
493       if (base_load_addr != LLDB_INVALID_ADDRESS)
494         return process_sp->ReadMemory(base_load_addr + section_offset, dst,
495                                       dst_len, error);
496     }
497   } else {
498     const lldb::offset_t section_file_size = section->GetFileSize();
499     if (section_offset < section_file_size) {
500       const size_t section_bytes_left = section_file_size - section_offset;
501       size_t section_dst_len = dst_len;
502       if (section_dst_len > section_bytes_left)
503         section_dst_len = section_bytes_left;
504       return CopyData(section->GetFileOffset() + section_offset,
505                       section_dst_len, dst);
506     } else {
507       if (section->GetType() == eSectionTypeZeroFill) {
508         const uint64_t section_size = section->GetByteSize();
509         const uint64_t section_bytes_left = section_size - section_offset;
510         uint64_t section_dst_len = dst_len;
511         if (section_dst_len > section_bytes_left)
512           section_dst_len = section_bytes_left;
513         memset(dst, 0, section_dst_len);
514         return section_dst_len;
515       }
516     }
517   }
518   return 0;
519 }
520 
521 // Get the section data the file on disk
522 size_t ObjectFile::ReadSectionData(Section *section,
523                                    DataExtractor &section_data) {
524   // If some other objectfile owns this data, pass this to them.
525   if (section->GetObjectFile() != this)
526     return section->GetObjectFile()->ReadSectionData(section, section_data);
527 
528   if (!section->IsRelocated())
529     RelocateSection(section);
530 
531   if (IsInMemory()) {
532     ProcessSP process_sp(m_process_wp.lock());
533     if (process_sp) {
534       const addr_t base_load_addr =
535           section->GetLoadBaseAddress(&process_sp->GetTarget());
536       if (base_load_addr != LLDB_INVALID_ADDRESS) {
537         DataBufferSP data_sp(
538             ReadMemory(process_sp, base_load_addr, section->GetByteSize()));
539         if (data_sp) {
540           section_data.SetData(data_sp, 0, data_sp->GetByteSize());
541           section_data.SetByteOrder(process_sp->GetByteOrder());
542           section_data.SetAddressByteSize(process_sp->GetAddressByteSize());
543           return section_data.GetByteSize();
544         }
545       }
546     }
547   }
548 
549   // The object file now contains a full mmap'ed copy of the object file
550   // data, so just use this
551   return GetData(section->GetFileOffset(), section->GetFileSize(),
552                   section_data);
553 }
554 
555 bool ObjectFile::SplitArchivePathWithObject(llvm::StringRef path_with_object,
556                                             FileSpec &archive_file,
557                                             ConstString &archive_object,
558                                             bool must_exist) {
559   size_t len = path_with_object.size();
560   if (len < 2 || path_with_object.back() != ')')
561     return false;
562   llvm::StringRef archive = path_with_object.substr(0, path_with_object.rfind('('));
563   if (archive.empty())
564     return false;
565   llvm::StringRef object = path_with_object.substr(archive.size() + 1).drop_back();
566   archive_file.SetFile(archive, FileSpec::Style::native);
567   if (must_exist && !FileSystem::Instance().Exists(archive_file))
568     return false;
569   archive_object.SetString(object);
570   return true;
571 }
572 
573 void ObjectFile::ClearSymtab() {
574   ModuleSP module_sp(GetModule());
575   if (module_sp) {
576     Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT));
577     LLDB_LOGF(log, "%p ObjectFile::ClearSymtab () symtab = %p",
578               static_cast<void *>(this),
579               static_cast<void *>(m_symtab_up.get()));
580     // Since we need to clear the symbol table, we need a new llvm::once_flag
581     // instance so we can safely create another symbol table
582     m_symtab_once_up.reset(new llvm::once_flag());
583     m_symtab_up.reset();
584   }
585 }
586 
587 SectionList *ObjectFile::GetSectionList(bool update_module_section_list) {
588   if (m_sections_up == nullptr) {
589     if (update_module_section_list) {
590       ModuleSP module_sp(GetModule());
591       if (module_sp) {
592         std::lock_guard<std::recursive_mutex> guard(module_sp->GetMutex());
593         CreateSections(*module_sp->GetUnifiedSectionList());
594       }
595     } else {
596       SectionList unified_section_list;
597       CreateSections(unified_section_list);
598     }
599   }
600   return m_sections_up.get();
601 }
602 
603 lldb::SymbolType
604 ObjectFile::GetSymbolTypeFromName(llvm::StringRef name,
605                                   lldb::SymbolType symbol_type_hint) {
606   if (!name.empty()) {
607     if (name.startswith("_OBJC_")) {
608       // ObjC
609       if (name.startswith("_OBJC_CLASS_$_"))
610         return lldb::eSymbolTypeObjCClass;
611       if (name.startswith("_OBJC_METACLASS_$_"))
612         return lldb::eSymbolTypeObjCMetaClass;
613       if (name.startswith("_OBJC_IVAR_$_"))
614         return lldb::eSymbolTypeObjCIVar;
615     } else if (name.startswith(".objc_class_name_")) {
616       // ObjC v1
617       return lldb::eSymbolTypeObjCClass;
618     }
619   }
620   return symbol_type_hint;
621 }
622 
623 std::vector<ObjectFile::LoadableData>
624 ObjectFile::GetLoadableData(Target &target) {
625   std::vector<LoadableData> loadables;
626   SectionList *section_list = GetSectionList();
627   if (!section_list)
628     return loadables;
629   // Create a list of loadable data from loadable sections
630   size_t section_count = section_list->GetNumSections(0);
631   for (size_t i = 0; i < section_count; ++i) {
632     LoadableData loadable;
633     SectionSP section_sp = section_list->GetSectionAtIndex(i);
634     loadable.Dest =
635         target.GetSectionLoadList().GetSectionLoadAddress(section_sp);
636     if (loadable.Dest == LLDB_INVALID_ADDRESS)
637       continue;
638     // We can skip sections like bss
639     if (section_sp->GetFileSize() == 0)
640       continue;
641     DataExtractor section_data;
642     section_sp->GetSectionData(section_data);
643     loadable.Contents = llvm::ArrayRef<uint8_t>(section_data.GetDataStart(),
644                                                 section_data.GetByteSize());
645     loadables.push_back(loadable);
646   }
647   return loadables;
648 }
649 
650 std::unique_ptr<CallFrameInfo> ObjectFile::CreateCallFrameInfo() {
651   return {};
652 }
653 
654 void ObjectFile::RelocateSection(lldb_private::Section *section)
655 {
656 }
657 
658 DataBufferSP ObjectFile::MapFileData(const FileSpec &file, uint64_t Size,
659                                      uint64_t Offset) {
660   return FileSystem::Instance().CreateDataBuffer(file.GetPath(), Size, Offset);
661 }
662 
663 void llvm::format_provider<ObjectFile::Type>::format(
664     const ObjectFile::Type &type, raw_ostream &OS, StringRef Style) {
665   switch (type) {
666   case ObjectFile::eTypeInvalid:
667     OS << "invalid";
668     break;
669   case ObjectFile::eTypeCoreFile:
670     OS << "core file";
671     break;
672   case ObjectFile::eTypeExecutable:
673     OS << "executable";
674     break;
675   case ObjectFile::eTypeDebugInfo:
676     OS << "debug info";
677     break;
678   case ObjectFile::eTypeDynamicLinker:
679     OS << "dynamic linker";
680     break;
681   case ObjectFile::eTypeObjectFile:
682     OS << "object file";
683     break;
684   case ObjectFile::eTypeSharedLibrary:
685     OS << "shared library";
686     break;
687   case ObjectFile::eTypeStubLibrary:
688     OS << "stub library";
689     break;
690   case ObjectFile::eTypeJIT:
691     OS << "jit";
692     break;
693   case ObjectFile::eTypeUnknown:
694     OS << "unknown";
695     break;
696   }
697 }
698 
699 void llvm::format_provider<ObjectFile::Strata>::format(
700     const ObjectFile::Strata &strata, raw_ostream &OS, StringRef Style) {
701   switch (strata) {
702   case ObjectFile::eStrataInvalid:
703     OS << "invalid";
704     break;
705   case ObjectFile::eStrataUnknown:
706     OS << "unknown";
707     break;
708   case ObjectFile::eStrataUser:
709     OS << "user";
710     break;
711   case ObjectFile::eStrataKernel:
712     OS << "kernel";
713     break;
714   case ObjectFile::eStrataRawImage:
715     OS << "raw image";
716     break;
717   case ObjectFile::eStrataJIT:
718     OS << "jit";
719     break;
720   }
721 }
722 
723 
724 Symtab *ObjectFile::GetSymtab() {
725   ModuleSP module_sp(GetModule());
726   if (module_sp) {
727     // We can't take the module lock in ObjectFile::GetSymtab() or we can
728     // deadlock in DWARF indexing when any file asks for the symbol table from
729     // an object file. This currently happens in the preloading of symbols in
730     // SymbolFileDWARF::PreloadSymbols() because the main thread will take the
731     // module lock, and then threads will be spun up to index the DWARF and
732     // any of those threads might end up trying to relocate items in the DWARF
733     // sections which causes ObjectFile::GetSectionData(...) to relocate section
734     // data which requires the symbol table.
735     //
736     // So to work around this, we create the symbol table one time using
737     // llvm::once_flag, lock it, and then set the unique pointer. Any other
738     // thread that gets ahold of the symbol table before parsing is done, will
739     // not be able to access the symbol table contents since all APIs in Symtab
740     // are protected by a mutex in the Symtab object itself.
741     llvm::call_once(*m_symtab_once_up, [&]() {
742       Symtab *symtab = new Symtab(this);
743       std::lock_guard<std::recursive_mutex> symtab_guard(symtab->GetMutex());
744       m_symtab_up.reset(symtab);
745       if (!m_symtab_up->LoadFromCache()) {
746         ElapsedTime elapsed(module_sp->GetSymtabParseTime());
747         ParseSymtab(*m_symtab_up);
748         m_symtab_up->Finalize();
749       }
750     });
751   }
752   return m_symtab_up.get();
753 }
754 
755 uint32_t ObjectFile::GetCacheHash() {
756   if (m_cache_hash)
757     return *m_cache_hash;
758   StreamString strm;
759   strm.Format("{0}-{1}-{2}", m_file, GetType(), GetStrata());
760   m_cache_hash = llvm::djbHash(strm.GetString());
761   return *m_cache_hash;
762 }
763