contrib/llvm/tools/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwp.cpp

   1 //===-- SymbolFileDWARFDwp.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 "SymbolFileDWARFDwp.h"
  11
  12 #include "lldb/Core/Section.h"
  13 #include "lldb/Symbol/ObjectFile.h"
  14
  15 #include "SymbolFileDWARFDwoDwp.h"
  16
  17 static llvm::DWARFSectionKind
  18 lldbSectTypeToLlvmSectionKind(lldb::SectionType type) {
  19   switch (type) {
  20   case lldb::eSectionTypeDWARFDebugInfo:
  21     return llvm::DW_SECT_INFO;
  22   // case lldb::eSectionTypeDWARFDebugTypes:
  23   //   return llvm::DW_SECT_TYPES;
  24   case lldb::eSectionTypeDWARFDebugAbbrev:
  25     return llvm::DW_SECT_ABBREV;
  26   case lldb::eSectionTypeDWARFDebugLine:
  27     return llvm::DW_SECT_LINE;
  28   case lldb::eSectionTypeDWARFDebugLoc:
  29     return llvm::DW_SECT_LOC;
  30   case lldb::eSectionTypeDWARFDebugStrOffsets:
  31     return llvm::DW_SECT_STR_OFFSETS;
  32   // case lldb::eSectionTypeDWARFDebugMacinfo:
  33   //   return llvm::DW_SECT_MACINFO;
  34   case lldb::eSectionTypeDWARFDebugMacro:
  35     return llvm::DW_SECT_MACRO;
  36   default:
  37     // Note: 0 is an invalid dwarf section kind.
  38     return llvm::DWARFSectionKind(0);
  39   }
  40 }
  41
  42 std::unique_ptr<SymbolFileDWARFDwp>
  43 SymbolFileDWARFDwp::Create(lldb::ModuleSP module_sp,
  44                            const lldb_private::FileSpec &file_spec) {
  45   const lldb::offset_t file_offset = 0;
  46   lldb::DataBufferSP file_data_sp;
  47   lldb::offset_t file_data_offset = 0;
  48   lldb::ObjectFileSP obj_file = lldb_private::ObjectFile::FindPlugin(
  49       module_sp, &file_spec, file_offset,
  50       lldb_private::FileSystem::Instance().GetByteSize(file_spec), file_data_sp,
  51       file_data_offset);
  52   if (obj_file == nullptr)
  53     return nullptr;
  54
  55   std::unique_ptr<SymbolFileDWARFDwp> dwp_symfile(
  56       new SymbolFileDWARFDwp(module_sp, obj_file));
  57
  58   lldb_private::DWARFDataExtractor debug_cu_index;
  59   if (!dwp_symfile->LoadRawSectionData(lldb::eSectionTypeDWARFDebugCuIndex,
  60                                        debug_cu_index))
  61     return nullptr;
  62
  63   llvm::DataExtractor llvm_debug_cu_index(
  64       llvm::StringRef(debug_cu_index.PeekCStr(0), debug_cu_index.GetByteSize()),
  65       debug_cu_index.GetByteOrder() == lldb::eByteOrderLittle,
  66       debug_cu_index.GetAddressByteSize());
  67   if (!dwp_symfile->m_debug_cu_index.parse(llvm_debug_cu_index))
  68     return nullptr;
  69   dwp_symfile->InitDebugCUIndexMap();
  70   return dwp_symfile;
  71 }
  72
  73 void SymbolFileDWARFDwp::InitDebugCUIndexMap() {
  74   m_debug_cu_index_map.clear();
  75   for (const auto &entry : m_debug_cu_index.getRows())
  76     m_debug_cu_index_map.emplace(entry.getSignature(), &entry);
  77 }
  78
  79 SymbolFileDWARFDwp::SymbolFileDWARFDwp(lldb::ModuleSP module_sp,
  80                                        lldb::ObjectFileSP obj_file)
  81     : m_obj_file(std::move(obj_file)), m_debug_cu_index(llvm::DW_SECT_INFO)
  82 {}
  83
  84 std::unique_ptr<SymbolFileDWARFDwo>
  85 SymbolFileDWARFDwp::GetSymbolFileForDwoId(DWARFUnit *dwarf_cu,
  86                                           uint64_t dwo_id) {
  87   return std::unique_ptr<SymbolFileDWARFDwo>(
  88       new SymbolFileDWARFDwoDwp(this, m_obj_file, dwarf_cu, dwo_id));
  89 }
  90
  91 bool SymbolFileDWARFDwp::LoadSectionData(
  92     uint64_t dwo_id, lldb::SectionType sect_type,
  93     lldb_private::DWARFDataExtractor &data) {
  94   lldb_private::DWARFDataExtractor section_data;
  95   if (!LoadRawSectionData(sect_type, section_data))
  96     return false;
  97
  98   auto it = m_debug_cu_index_map.find(dwo_id);
  99   if (it == m_debug_cu_index_map.end())
 100     return false;
 101
 102   auto *offsets =
 103       it->second->getOffset(lldbSectTypeToLlvmSectionKind(sect_type));
 104   if (offsets) {
 105     data.SetData(section_data, offsets->Offset, offsets->Length);
 106   } else {
 107     data.SetData(section_data, 0, section_data.GetByteSize());
 108   }
 109   return true;
 110 }
 111
 112 bool SymbolFileDWARFDwp::LoadRawSectionData(
 113     lldb::SectionType sect_type, lldb_private::DWARFDataExtractor &data) {
 114   std::lock_guard<std::mutex> lock(m_sections_mutex);
 115
 116   auto it = m_sections.find(sect_type);
 117   if (it != m_sections.end()) {
 118     if (it->second.GetByteSize() == 0)
 119       return false;
 120
 121     data = it->second;
 122     return true;
 123   }
 124
 125   const lldb_private::SectionList *section_list =
 126       m_obj_file->GetSectionList(false /* update_module_section_list */);
 127   if (section_list) {
 128     lldb::SectionSP section_sp(
 129         section_list->FindSectionByType(sect_type, true));
 130     if (section_sp) {
 131       if (m_obj_file->ReadSectionData(section_sp.get(), data) != 0) {
 132         m_sections[sect_type] = data;
 133         return true;
 134       }
 135     }
 136   }
 137   m_sections[sect_type].Clear();
 138   return false;
 139 }