dwarf2.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 1,670 行 · 第 1/3 页

    case DW_FORM_data4:
      DW_UNSND (attr) = read_4_bytes (abfd, info_ptr);
      info_ptr += 4;
      break;
    case DW_FORM_data8:
      DW_UNSND (attr) = read_8_bytes (abfd, info_ptr);
      info_ptr += 8;
      break;
    case DW_FORM_string:
      DW_STRING (attr) = read_string (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_block:
      blk = (struct dwarf_block *) bfd_alloc (abfd, sizeof (struct dwarf_block));
      blk->size = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      blk->data = read_n_bytes (abfd, info_ptr, blk->size);
      info_ptr += blk->size;
      DW_BLOCK (attr) = blk;
      break;
    case DW_FORM_block1:
      blk = (struct dwarf_block *) bfd_alloc (abfd, sizeof (struct dwarf_block));
      blk->size = read_1_byte (abfd, info_ptr);
      info_ptr += 1;
      blk->data = read_n_bytes (abfd, info_ptr, blk->size);
      info_ptr += blk->size;
      DW_BLOCK (attr) = blk;
      break;
    case DW_FORM_data1:
      DW_UNSND (attr) = read_1_byte (abfd, info_ptr);
      info_ptr += 1;
      break;
    case DW_FORM_flag:
      DW_UNSND (attr) = read_1_byte (abfd, info_ptr);
      info_ptr += 1;
      break;
    case DW_FORM_sdata:
      DW_SND (attr) = read_signed_leb128 (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_udata:
      DW_UNSND (attr) = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_ref1:
      DW_UNSND (attr) = read_1_byte (abfd, info_ptr);
      info_ptr += 1;
      break;
    case DW_FORM_ref2:
      DW_UNSND (attr) = read_2_bytes (abfd, info_ptr);
      info_ptr += 2;
      break;
    case DW_FORM_ref4:
      DW_UNSND (attr) = read_4_bytes (abfd, info_ptr);
      info_ptr += 4;
      break;
    case DW_FORM_ref8:
      DW_UNSND (attr) = read_8_bytes (abfd, info_ptr);
      info_ptr += 8;
      break;
    case DW_FORM_ref_udata:
      DW_UNSND (attr) = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_strp:
    case DW_FORM_indirect:
    default:
      (*_bfd_error_handler) (_("Dwarf Error: Invalid or unhandled FORM value: %d."),
			     abbrev->form);
      bfd_set_error (bfd_error_bad_value);
    }
  return info_ptr;
}

/* Source line information table routines.  */

#define FILE_ALLOC_CHUNK 5
#define DIR_ALLOC_CHUNK 5

struct line_info
{
  struct line_info* prev_line;
  bfd_vma address;
  char* filename;
  unsigned int line;
  unsigned int column;
  int end_sequence;		/* End of (sequential) code sequence.  */
};

struct fileinfo
{
  char *name;
  unsigned int dir;
  unsigned int time;
  unsigned int size;
};

struct line_info_table
{
  bfd* abfd;
  unsigned int num_files;
  unsigned int num_dirs;
  char* comp_dir;
  char** dirs;
  struct fileinfo* files;
  struct line_info* last_line;
};

static void
add_line_info (table, address, filename, line, column, end_sequence)
     struct line_info_table* table;
     bfd_vma address;
     char* filename;
     unsigned int line;
     unsigned int column;
     int end_sequence;
{
  struct line_info* info = (struct line_info*)
    bfd_alloc (table->abfd, sizeof (struct line_info));

  info->prev_line = table->last_line;
  table->last_line = info;

  info->address = address;
  info->filename = filename;
  info->line = line;
  info->column = column;
  info->end_sequence = end_sequence;
}

static char *
concat_filename (table, file)
     struct line_info_table* table;
     unsigned int file;
{
  char* filename;

  if (file - 1 >= table->num_files)
    {
      (*_bfd_error_handler)
	(_("Dwarf Error: mangled line number section (bad file number)."));
      return "<unknown>";
    }

  filename = table->files[file - 1].name;
  if (IS_ABSOLUTE_PATH(filename))
    return filename;

  else
    {
      char* dirname = (table->files[file - 1].dir
		       ? table->dirs[table->files[file - 1].dir - 1]
		       : table->comp_dir);
      return (char*) concat (dirname, "/", filename, NULL);
    }
}

static void
arange_add (unit, low_pc, high_pc)
     struct comp_unit *unit;
     bfd_vma low_pc;
     bfd_vma high_pc;
{
  struct arange *arange;

  /* First see if we can cheaply extend an existing range.  */
  arange = &unit->arange;

  do
    {
      if (low_pc == arange->high)
	{
	  arange->high = high_pc;
	  return;
	}
      if (high_pc == arange->low)
	{
	  arange->low = low_pc;
	  return;
	}
      arange = arange->next;
    }
  while (arange);

  if (unit->arange.high == 0)
    {
      /* This is the first address range: store it in unit->arange.  */
      unit->arange.next = 0;
      unit->arange.low = low_pc;
      unit->arange.high = high_pc;
      return;
    }

  /* Need to allocate a new arange and insert it into the arange list.  */
  arange = bfd_zalloc (unit->abfd, sizeof (*arange));
  arange->low = low_pc;
  arange->high = high_pc;

  arange->next = unit->arange.next;
  unit->arange.next = arange;
}

/* Decode the line number information for UNIT.  */

static struct line_info_table*
decode_line_info (unit, stash)
     struct comp_unit *unit;
     struct dwarf2_debug *stash;
{
  bfd *abfd = unit->abfd;
  struct line_info_table* table;
  char *line_ptr;
  char *line_end;
  struct line_head lh;
  unsigned int i, bytes_read;
  char *cur_file, *cur_dir;
  unsigned char op_code, extended_op, adj_opcode;

  if (! stash->dwarf_line_buffer)
    {
      asection *msec;

      msec = bfd_get_section_by_name (abfd, ".debug_line");
      if (! msec)
	{
	  (*_bfd_error_handler) (_("Dwarf Error: Can't find .debug_line section."));
	  bfd_set_error (bfd_error_bad_value);
	  return 0;
	}

      stash->dwarf_line_size = msec->_raw_size;
      stash->dwarf_line_buffer = (char *) bfd_alloc (abfd, stash->dwarf_line_size);
      if (! stash->dwarf_line_buffer)
	return 0;

      if (! bfd_get_section_contents (abfd, msec,
				      stash->dwarf_line_buffer, 0,
				      stash->dwarf_line_size))
	return 0;

      /* FIXME: We ought to apply the relocs against this section before
	 we process it...  */
    }

  /* Since we are using un-relocated data, it is possible to get a bad value
     for the line_offset.  Validate it here so that we won't get a segfault
     below.  */
  if (unit->line_offset >= stash->dwarf_line_size)
    {
      (*_bfd_error_handler) (_("Dwarf Error: Line offset (%u) greater than or equal to line size (%u)."),
			     unit->line_offset, stash->dwarf_line_size);
      bfd_set_error (bfd_error_bad_value);
      return 0;
    }

  table = (struct line_info_table*) bfd_alloc (abfd,
					       sizeof (struct line_info_table));
  table->abfd = abfd;
  table->comp_dir = unit->comp_dir;

  table->num_files = 0;
  table->files = NULL;

  table->num_dirs = 0;
  table->dirs = NULL;

  table->files = NULL;
  table->last_line = NULL;

  line_ptr = stash->dwarf_line_buffer + unit->line_offset;

  /* Read in the prologue.  */
  lh.total_length = read_4_bytes (abfd, line_ptr);
  line_ptr += 4;
  line_end = line_ptr + lh.total_length;
  lh.version = read_2_bytes (abfd, line_ptr);
  line_ptr += 2;
  lh.prologue_length = read_4_bytes (abfd, line_ptr);
  line_ptr += 4;
  lh.minimum_instruction_length = read_1_byte (abfd, line_ptr);
  line_ptr += 1;
  lh.default_is_stmt = read_1_byte (abfd, line_ptr);
  line_ptr += 1;
  lh.line_base = read_1_signed_byte (abfd, line_ptr);
  line_ptr += 1;
  lh.line_range = read_1_byte (abfd, line_ptr);
  line_ptr += 1;
  lh.opcode_base = read_1_byte (abfd, line_ptr);
  line_ptr += 1;
  lh.standard_opcode_lengths = (unsigned char *)
    bfd_alloc (abfd, lh.opcode_base * sizeof (unsigned char));

  lh.standard_opcode_lengths[0] = 1;

  for (i = 1; i < lh.opcode_base; ++i)
    {
      lh.standard_opcode_lengths[i] = read_1_byte (abfd, line_ptr);
      line_ptr += 1;
    }

  /* Read directory table.  */
  while ((cur_dir = read_string (abfd, line_ptr, &bytes_read)) != NULL)
    {
      line_ptr += bytes_read;

      if ((table->num_dirs % DIR_ALLOC_CHUNK) == 0)
	{
	  table->dirs = (char **)
	    bfd_realloc (table->dirs,
			 (table->num_dirs + DIR_ALLOC_CHUNK) * sizeof (char *));
	  if (! table->dirs)
	    return 0;
	}

      table->dirs[table->num_dirs++] = cur_dir;
    }

  line_ptr += bytes_read;

  /* Read file name table.  */
  while ((cur_file = read_string (abfd, line_ptr, &bytes_read)) != NULL)
    {
      line_ptr += bytes_read;

      if ((table->num_files % FILE_ALLOC_CHUNK) == 0)
	{
	  table->files = (struct fileinfo *)
	    bfd_realloc (table->files,
			 (table->num_files + FILE_ALLOC_CHUNK)
			 * sizeof (struct fileinfo));
	  if (! table->files)
	    return 0;
	}

      table->files[table->num_files].name = cur_file;
      table->files[table->num_files].dir =
	read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
      line_ptr += bytes_read;
      table->files[table->num_files].time =
	read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
      line_ptr += bytes_read;
      table->files[table->num_files].size =
	read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
      line_ptr += bytes_read;
      table->num_files++;
    }

  line_ptr += bytes_read;

  /* Read the statement sequences until there's nothing left.  */
  while (line_ptr < line_end)
    {
      /* State machine registers.  */
      bfd_vma address = 0;
      char* filename = concat_filename (table, 1);
      unsigned int line = 1;
      unsigned int column = 0;
      int is_stmt = lh.default_is_stmt;
      int basic_block = 0;
      int end_sequence = 0, need_low_pc = 1;
      bfd_vma low_pc = 0;

      /* Decode the table.  */
      while (! end_sequence)
	{
	  op_code = read_1_byte (abfd, line_ptr);
	  line_ptr += 1;

	  switch (op_code)
	    {
	    case DW_LNS_extended_op:
	      line_ptr += 1;	/* Ignore length.  */
	      extended_op = read_1_byte (abfd, line_ptr);
	      line_ptr += 1;
	      switch (extended_op)
		{
		case DW_LNE_end_sequence:
		  end_sequence = 1;
		  add_line_info (table, address, filename, line, column,
				 end_sequence);
		  if (need_low_pc)
		    {
		      need_low_pc = 0;
		      low_pc = address;
		    }
		  arange_add (unit, low_pc, address);
		  break;
		case DW_LNE_set_address:
		  address = read_address (unit, line_ptr);
		  line_ptr += unit->addr_size;
		  break;
		case DW_LNE_define_file:
		  cur_file = read_string (abfd, line_ptr, &bytes_read);
		  line_ptr += bytes_read;
		  if ((table->num_files % FILE_ALLOC_CHUNK) == 0)
		    {
		      table->files = (struct fileinfo *)
			bfd_realloc (table->files,
				     (table->num_files + FILE_ALLOC_CHUNK)
				     * sizeof (struct fileinfo));
		      if (! table->files)
			return 0;
		    }
		  table->files[table->num_files].name = cur_file;
		  table->files[table->num_files].dir =
		    read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
		  line_ptr += bytes_read;
		  table->files[table->num_files].time =
		    read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
		  line_ptr += bytes_read;
		  table->files[table->num_files].size =
		    read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
		  line_ptr += bytes_read;
		  table->num_files++;
		  break;
		default:
		  (*_bfd_error_handler) (_("Dwarf Error: mangled line number section."));
		  bfd_set_error (bfd_error_bad_value);
		  return 0;
		}
	      break;
	    case DW_LNS_copy:
	      add_line_info (table, address, filename, line, column, 0);
	      basic_block = 0;
	      if (need_low_pc)
		{
		  need_low_pc = 0;
		  low_pc = address;
		}
	      break;
	    case DW_LNS_advance_pc:
	      address += lh.minimum_instruction_length
		* read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
	      line_ptr += bytes_read;
	      break;
	    case DW_LNS_advance_line:
	      line += read_signed_leb128 (abfd, line_ptr, &bytes_read);
	      line_ptr += bytes_read;
	      break;
	    case DW_LNS_set_file:
	      {
		unsigned int file;

		/* The file and directory tables are 0 based, the references
		   are 1 based.  */
		file = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
		line_ptr += bytes_read;
		filename = concat_filename (table, file);
		break;
	      }
	    case DW_LNS_set_column:
	      column = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
	      line_ptr += bytes_read;
	      break;
	    case DW_LNS_negate_stmt:
	      is_stmt = (!is_stmt);
	      break;
	    case DW_LNS_set_basic_block:
	      basic_block = 1;
	      break;
	    case DW_LNS_const_add_pc:
	      address += lh.minimum_instruction_length
		      * ((255 - lh.opcode_base) / lh.line_range);
	      break;
	    case DW_LNS_fixed_advance_pc:
	      address += read_2_bytes (abfd, line_ptr);
	      line_ptr += 2;
	      break;
	    default:		/* Special operand.  */
	      adj_opcode = op_code - lh.opcode_base;
	      address += (adj_opcode / lh.line_range)
		* lh.minimum_instruction_length;
	      line += lh.line_base + (adj_opcode % lh.line_range);
	      /* Append row to matrix using current values.  */
	      add_line_info (table, address, filename, line, column, 0);
	      basic_block = 1;
	      if (need_low_pc)
		{
		  need_low_pc = 0;
		  low_pc = address;
		}
	    }
	}
    }

  return table;
}

/* If ADDR is within TABLE set the output parameters and return true,
   otherwise return false.  The output parameters, FILENAME_PTR and
   LINENUMBER_PTR, are pointers to the objects to be filled in.  */

static boolean
lookup_address_in_line_info_table (table,
				   addr,
				   filename_ptr,
				   linenumber_ptr)
     struct line_info_table* table;
     bfd_vma addr;
     const char **filename_ptr;
     unsigned int *linenumber_ptr;
{
  struct line_info* next_line = table->last_line;
  struct line_info* each_line;

  if (!next_line)
    return false;

  each_line = next_line->prev_line;

  while (each_line && next_line)
    {
      if (!each_line->end_sequence
	  && addr >= each_line->address && addr < next_line->address)
	{
	  *filename_ptr = each_line->filename;
	  *linenumber_ptr = each_line->line;
	  return true;
	}
      next_line = each_line;
      each_line = each_line->prev_line;
    }

  return false;
}

/* Function table functions.  */

struct funcinfo
{
  struct funcinfo *prev_func;
  char* name;
  bfd_vma low;
  bfd_vma high;
};

/* If ADDR is within TABLE, set FUNCTIONNAME_PTR, and return true.  */

static boolean
lookup_address_in_function_table (table,
				  addr,
				  functionname_ptr)
     struct funcinfo* table;
     bfd_vma addr;
     const char **functionname_ptr;
{
  struct funcinfo* each_func;

  for (each_func = table;
       each_func;
       each_func = each_func->prev_func)
    {
      if (addr >= each_func->low && addr < each_func->high)
	{
	  *functionname_ptr = each_func->name;
	  return true;
	}