source/Plugins/SymbolFile/DWARF/DWARFDebugMacro.cpp

   1 //===-- DWARFDebugMacro.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 "DWARFDebugMacro.h"
  11 #include "SymbolFileDWARF.h"
  12
  13 #include "lldb/Symbol/DebugMacros.h"
  14
  15 #include "DWARFDataExtractor.h"
  16
  17 using namespace lldb_private;
  18
  19 DWARFDebugMacroHeader
  20 DWARFDebugMacroHeader::ParseHeader(const DWARFDataExtractor &debug_macro_data, lldb::offset_t *offset)
  21 {
  22     DWARFDebugMacroHeader header;
  23
  24     // Skip over the version field in header.
  25     header.m_version = debug_macro_data.GetU16(offset);
  26
  27     uint8_t flags = debug_macro_data.GetU8(offset);
  28     header.m_offset_is_64_bit = flags & OFFSET_SIZE_MASK ? true : false;
  29
  30     if (flags & DEBUG_LINE_OFFSET_MASK)
  31     {
  32         if (header.m_offset_is_64_bit)
  33             header.m_debug_line_offset = debug_macro_data.GetU64(offset);
  34         else
  35             header.m_debug_line_offset = debug_macro_data.GetU32(offset);
  36     }
  37
  38     // Skip over the operands table if it is present.
  39     if (flags & OPCODE_OPERANDS_TABLE_MASK)
  40         SkipOperandTable(debug_macro_data, offset);
  41
  42     return header;
  43 }
  44
  45 void
  46 DWARFDebugMacroHeader::SkipOperandTable(const DWARFDataExtractor &debug_macro_data, lldb::offset_t *offset)
  47 {
  48     uint8_t entry_count = debug_macro_data.GetU8(offset);
  49     for (uint8_t i = 0; i < entry_count; i++)
  50     {
  51         // Skip over the opcode number.
  52         debug_macro_data.GetU8(offset);
  53
  54         uint64_t operand_count = debug_macro_data.GetULEB128(offset);
  55
  56         for (uint64_t j = 0; j < operand_count; j++)
  57         {
  58             // Skip over the operand form
  59             debug_macro_data.GetU8(offset);
  60         }
  61     }
  62 }
  63
  64 void
  65 DWARFDebugMacroEntry::ReadMacroEntries(const DWARFDataExtractor &debug_macro_data,
  66                                        const DWARFDataExtractor &debug_str_data,
  67                                        const bool offset_is_64_bit,
  68                                        lldb::offset_t *offset,
  69                                        SymbolFileDWARF *sym_file_dwarf,
  70                                        DebugMacrosSP &debug_macros_sp)
  71 {
  72     llvm::dwarf::MacroEntryType type = static_cast<llvm::dwarf::MacroEntryType>(debug_macro_data.GetU8(offset));
  73     while (type != 0)
  74     {
  75         lldb::offset_t new_offset = 0, str_offset = 0;
  76         uint32_t line = 0;
  77         const char *macro_str = nullptr;
  78         uint32_t debug_line_file_idx = 0;
  79
  80         switch (type)
  81         {
  82             case DW_MACRO_define:
  83             case DW_MACRO_undef:
  84                 line = debug_macro_data.GetULEB128(offset);
  85                 macro_str = debug_macro_data.GetCStr(offset);
  86                 if (type == DW_MACRO_define)
  87                     debug_macros_sp->AddMacroEntry(DebugMacroEntry::CreateDefineEntry(line, macro_str));
  88                 else
  89                     debug_macros_sp->AddMacroEntry(DebugMacroEntry::CreateUndefEntry(line, macro_str));
  90                 break;
  91             case DW_MACRO_define_indirect:
  92             case DW_MACRO_undef_indirect:
  93                 line = debug_macro_data.GetULEB128(offset);
  94                 if (offset_is_64_bit)
  95                     str_offset = debug_macro_data.GetU64(offset);
  96                 else
  97                     str_offset = debug_macro_data.GetU32(offset);
  98                 macro_str = debug_str_data.GetCStr(&str_offset);
  99                 if (type == DW_MACRO_define_indirect)
 100                     debug_macros_sp->AddMacroEntry(DebugMacroEntry::CreateDefineEntry(line, macro_str));
 101                 else
 102                     debug_macros_sp->AddMacroEntry(DebugMacroEntry::CreateUndefEntry(line, macro_str));
 103                 break;
 104             case DW_MACRO_start_file:
 105                 line = debug_macro_data.GetULEB128(offset);
 106                 debug_line_file_idx = debug_macro_data.GetULEB128(offset);
 107                 debug_macros_sp->AddMacroEntry(DebugMacroEntry::CreateStartFileEntry(line, debug_line_file_idx));
 108                 break;
 109             case DW_MACRO_end_file:
 110                 // This operation has no operands.
 111                 debug_macros_sp->AddMacroEntry(DebugMacroEntry::CreateEndFileEntry());
 112                 break;
 113             case DW_MACRO_transparent_include:
 114                 if (offset_is_64_bit)
 115                     new_offset = debug_macro_data.GetU64(offset);
 116                 else
 117                     new_offset = debug_macro_data.GetU32(offset);
 118                 debug_macros_sp->AddMacroEntry(
 119                     DebugMacroEntry::CreateIndirectEntry(sym_file_dwarf->ParseDebugMacros(&new_offset)));
 120                 break;
 121             default:
 122                 // TODO: Add support for other standard operations.
 123                 // TODO: Provide mechanism to hook handling of non-standard/extension operands.
 124                 return;
 125         }
 126         type = static_cast<llvm::dwarf::MacroEntryType>(debug_macro_data.GetU8(offset));
 127     }
 128 }