obj-elf.c

基于4个mips核的noc设计

{
  segT new_section;
  int new_subsection;

  if (previous_section == 0)
    {
      as_bad (_(".previous without corresponding .section; ignored"));
      return;
    }

#ifdef md_flush_pending_output
  md_flush_pending_output ();
#endif

  new_section = previous_section;
  new_subsection = previous_subsection;
  previous_section = now_seg;
  previous_subsection = now_subseg;
  subseg_set (new_section, new_subsection);

#ifdef md_elf_section_change_hook
  md_elf_section_change_hook ();
#endif
}

static void
obj_elf_popsection (xxx)
     int xxx ATTRIBUTE_UNUSED;
{
  struct section_stack *top = section_stack;

  if (top == NULL)
    {
      as_bad (_(".popsection without corresponding .pushsection; ignored"));
      return;
    }

#ifdef md_flush_pending_output
  md_flush_pending_output ();
#endif

  section_stack = top->next;
  previous_section = top->prev_seg;
  previous_subsection = top->prev_subseg;
  subseg_set (top->seg, top->subseg);
  free (top);

#ifdef md_elf_section_change_hook
  md_elf_section_change_hook ();
#endif
}

static void
obj_elf_line (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  /* Assume delimiter is part of expression.  BSD4.2 as fails with
     delightful bug, so we are not being incompatible here.  */
  new_logical_line ((char *) NULL, (int) (get_absolute_expression ()));
  demand_empty_rest_of_line ();
}

/* This handles the .symver pseudo-op, which is used to specify a
   symbol version.  The syntax is ``.symver NAME,SYMVERNAME''.
   SYMVERNAME may contain ELF_VER_CHR ('@') characters.  This
   pseudo-op causes the assembler to emit a symbol named SYMVERNAME
   with the same value as the symbol NAME.  */

static void
obj_elf_symver (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  char *name;
  char c;
  symbolS *sym;

  name = input_line_pointer;
  c = get_symbol_end ();

  sym = symbol_find_or_make (name);

  *input_line_pointer = c;

  SKIP_WHITESPACE ();
  if (*input_line_pointer != ',')
    {
      as_bad (_("expected comma after name in .symver"));
      ignore_rest_of_line ();
      return;
    }

  ++input_line_pointer;
  name = input_line_pointer;
  while (1)
    {
      c = get_symbol_end ();
      if (c != ELF_VER_CHR)
	break;
      *input_line_pointer++ = c;
    }

  if (symbol_get_obj (sym)->versioned_name == NULL)
    {
      symbol_get_obj (sym)->versioned_name = xstrdup (name);

      *input_line_pointer = c;

      if (strchr (symbol_get_obj (sym)->versioned_name,
		  ELF_VER_CHR) == NULL)
	{
	  as_bad (_("missing version name in `%s' for symbol `%s'"),
		  symbol_get_obj (sym)->versioned_name,
		  S_GET_NAME (sym));
	  ignore_rest_of_line ();
	  return;
	}
    }
  else
    {
      if (strcmp (symbol_get_obj (sym)->versioned_name, name))
	{
	  as_bad (_("multiple versions [`%s'|`%s'] for symbol `%s'"),
		  name, symbol_get_obj (sym)->versioned_name,
		  S_GET_NAME (sym));
	  ignore_rest_of_line ();
	  return;
	}

      *input_line_pointer = c;
    }

  demand_empty_rest_of_line ();
}

/* This handles the .vtable_inherit pseudo-op, which is used to indicate
   to the linker the hierarchy in which a particular table resides.  The
   syntax is ".vtable_inherit CHILDNAME, PARENTNAME".  */

struct fix *
obj_elf_vtable_inherit (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  char *cname, *pname;
  symbolS *csym, *psym;
  char c, bad = 0;

  if (*input_line_pointer == '#')
    ++input_line_pointer;

  cname = input_line_pointer;
  c = get_symbol_end ();
  csym = symbol_find (cname);

  /* GCFIXME: should check that we don't have two .vtable_inherits for
     the same child symbol.  Also, we can currently only do this if the
     child symbol is already exists and is placed in a fragment.  */

  if (csym == NULL || symbol_get_frag (csym) == NULL)
    {
      as_bad ("expected `%s' to have already been set for .vtable_inherit",
	      cname);
      bad = 1;
    }

  *input_line_pointer = c;

  SKIP_WHITESPACE ();
  if (*input_line_pointer != ',')
    {
      as_bad ("expected comma after name in .vtable_inherit");
      ignore_rest_of_line ();
      return NULL;
    }

  ++input_line_pointer;
  SKIP_WHITESPACE ();

  if (*input_line_pointer == '#')
    ++input_line_pointer;

  if (input_line_pointer[0] == '0'
      && (input_line_pointer[1] == '\0'
	  || isspace ((unsigned char) input_line_pointer[1])))
    {
      psym = section_symbol (absolute_section);
      ++input_line_pointer;
    }
  else
    {
      pname = input_line_pointer;
      c = get_symbol_end ();
      psym = symbol_find_or_make (pname);
      *input_line_pointer = c;
    }

  demand_empty_rest_of_line ();

  if (bad)
    return NULL;

  assert (symbol_get_value_expression (csym)->X_op == O_constant);
  return fix_new (symbol_get_frag (csym),
		  symbol_get_value_expression (csym)->X_add_number,
		  0, psym, 0, 0, BFD_RELOC_VTABLE_INHERIT);
}

/* This handles the .vtable_entry pseudo-op, which is used to indicate
   to the linker that a vtable slot was used.  The syntax is
   ".vtable_entry tablename, offset".  */

struct fix *
obj_elf_vtable_entry (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  char *name;
  symbolS *sym;
  offsetT offset;
  char c;

  if (*input_line_pointer == '#')
    ++input_line_pointer;

  name = input_line_pointer;
  c = get_symbol_end ();
  sym = symbol_find_or_make (name);
  *input_line_pointer = c;

  SKIP_WHITESPACE ();
  if (*input_line_pointer != ',')
    {
      as_bad ("expected comma after name in .vtable_entry");
      ignore_rest_of_line ();
      return NULL;
    }

  ++input_line_pointer;
  if (*input_line_pointer == '#')
    ++input_line_pointer;

  offset = get_absolute_expression ();

  demand_empty_rest_of_line ();

  return fix_new (frag_now, frag_now_fix (), 0, sym, offset, 0,
		  BFD_RELOC_VTABLE_ENTRY);
}

void
elf_obj_read_begin_hook ()
{
#ifdef NEED_ECOFF_DEBUG
  if (ECOFF_DEBUGGING)
    ecoff_read_begin_hook ();
#endif
}

void
elf_obj_symbol_new_hook (symbolP)
     symbolS *symbolP;
{
  struct elf_obj_sy *sy_obj;

  sy_obj = symbol_get_obj (symbolP);
  sy_obj->size = NULL;
  sy_obj->versioned_name = NULL;

#ifdef NEED_ECOFF_DEBUG
  if (ECOFF_DEBUGGING)
    ecoff_symbol_new_hook (symbolP);
#endif
}

void
obj_elf_version (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  char *name;
  unsigned int c;
  char ch;
  char *p;
  asection *seg = now_seg;
  subsegT subseg = now_subseg;
  Elf_Internal_Note i_note;
  Elf_External_Note e_note;
  asection *note_secp = (asection *) NULL;
  int i, len;

  SKIP_WHITESPACE ();
  if (*input_line_pointer == '\"')
    {
      ++input_line_pointer;	/* -> 1st char of string.  */
      name = input_line_pointer;

      while (is_a_char (c = next_char_of_string ()))
	;
      c = *input_line_pointer;
      *input_line_pointer = '\0';
      *(input_line_pointer - 1) = '\0';
      *input_line_pointer = c;

      /* create the .note section */

      note_secp = subseg_new (".note", 0);
      bfd_set_section_flags (stdoutput,
			     note_secp,
			     SEC_HAS_CONTENTS | SEC_READONLY);

      /* process the version string */

      len = strlen (name);

      i_note.namesz = ((len + 1) + 3) & ~3; /* round this to word boundary */
      i_note.descsz = 0;	/* no description */
      i_note.type = NT_VERSION;
      p = frag_more (sizeof (e_note.namesz));
      md_number_to_chars (p, (valueT) i_note.namesz, 4);
      p = frag_more (sizeof (e_note.descsz));
      md_number_to_chars (p, (valueT) i_note.descsz, 4);
      p = frag_more (sizeof (e_note.type));
      md_number_to_chars (p, (valueT) i_note.type, 4);

      for (i = 0; i < len; i++)
	{
	  ch = *(name + i);
	  {
	    FRAG_APPEND_1_CHAR (ch);
	  }
	}
      frag_align (2, 0, 0);

      subseg_set (seg, subseg);
    }
  else
    {
      as_bad (_("Expected quoted string"));
    }
  demand_empty_rest_of_line ();
}

static void
obj_elf_size (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  char *name = input_line_pointer;
  char c = get_symbol_end ();
  char *p;
  expressionS exp;
  symbolS *sym;

  p = input_line_pointer;
  *p = c;
  SKIP_WHITESPACE ();
  if (*input_line_pointer != ',')
    {
      *p = 0;
      as_bad (_("expected comma after name `%s' in .size directive"), name);
      *p = c;
      ignore_rest_of_line ();
      return;
    }
  input_line_pointer++;
  expression (&exp);
  if (exp.X_op == O_absent)
    {
      as_bad (_("missing expression in .size directive"));
      exp.X_op = O_constant;
      exp.X_add_number = 0;
    }
  *p = 0;
  sym = symbol_find_or_make (name);
  *p = c;
  if (exp.X_op == O_constant)
    S_SET_SIZE (sym, exp.X_add_number);
  else
    {
      symbol_get_obj (sym)->size =
	(expressionS *) xmalloc (sizeof (expressionS));
      *symbol_get_obj (sym)->size = exp;
    }
  demand_empty_rest_of_line ();
}

/* Handle the ELF .type pseudo-op.  This sets the type of a symbol.
   There are five syntaxes:

   The first (used on Solaris) is
       .type SYM,#function
   The second (used on UnixWare) is
       .type SYM,@function
   The third (reportedly to be used on Irix 6.0) is
       .type SYM STT_FUNC
   The fourth (used on NetBSD/Arm and Linux/ARM) is
       .type SYM,%function
   The fifth (used on SVR4/860) is
       .type SYM,"function"
   */

static void
obj_elf_type (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  char *name;
  char c;
  int type;
  const char *typename;
  symbolS *sym;
  elf_symbol_type *elfsym;

  name = input_line_pointer;
  c = get_symbol_end ();
  sym = symbol_find_or_make (name);
  elfsym = (elf_symbol_type *) symbol_get_bfdsym (sym);
  *input_line_pointer = c;

  SKIP_WHITESPACE ();
  if (*input_line_pointer == ',')
    ++input_line_pointer;

  SKIP_WHITESPACE ();
  if (   *input_line_pointer == '#'
      || *input_line_pointer == '@'
      || *input_line_pointer == '"'
      || *input_line_pointer == '%')
    ++input_line_pointer;

  typename = input_line_pointer;
  c = get_symbol_end ();

  type = 0;
  if (strcmp (typename, "function") == 0
      || strcmp (typename, "STT_FUNC") == 0)
    type = BSF_FUNCTION;
  else if (strcmp (typename, "object") == 0
	   || strcmp (typename, "STT_OBJECT") == 0)
    type = BSF_OBJECT;
#ifdef md_elf_symbol_type
  else if ((type = md_elf_symbol_type (typename, sym, elfsym)) != -1)
    ;
#endif
  else
    as_bad (_("ignoring unrecognized symbol type \"%s\""), typename);

  *input_line_pointer = c;

  if (*input_line_pointer == '"')
    ++input_line_pointer;

  elfsym->symbol.flags |= type;

  demand_empty_rest_of_line ();
}

static void
obj_elf_ident (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  static segT comment_section;
  segT old_section = now_seg;
  int old_subsection = now_subseg;

#ifdef md_flush_pending_output
  md_flush_pending_output ();
#endif

  if (!comment_section)
    {
      char *p;
      comment_section = subseg_new (".comment", 0);
      bfd_set_section_flags (stdoutput, comment_section,
			     SEC_READONLY | SEC_HAS_CONTENTS);
      p = frag_more (1);
      *p = 0;
    }
  else
    subseg_set (comment_section, 0);
  stringer (1);
  subseg_set (old_section, old_subsection);
}

#ifdef INIT_STAB_SECTION

/* The first entry in a .stabs section is special.  */

void
obj_elf_init_stab_section (seg)
     segT seg;
{
  char *file;
  char *p;
  char *stabstr_name;
  unsigned int stroff;

  /* Force the section to align to a longword boundary.  Without this,
     UnixWare ar crashes.  */
  bfd_set_section_alignment (stdoutput, seg, 2);

  /* Make space for this first symbol.  */
  p = frag_more (12);
  /* Zero it out.  */
  memset (p, 0, 12);
  as_where (&file, (unsigned int *) NULL);
  stabstr_name = (char *) alloca (strlen (segment_name (seg)) + 4);
  strcpy (stabstr_name, segment_name (seg));
  strcat (stabstr_name, "str");
  stroff = get_stab_string_offset (file, stabstr_name);
  know (stroff == 1);
  md_number_to_chars (p, stroff, 4);
  seg_info (seg)->stabu.p = p;
}

#endif

/* Fill in the counts in the first entry in a .stabs section.  */