stabs.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 679 行 · 第 1/2 页

      stroff = get_stab_string_offset (string, stabstr_secname);
      if (what == 's')
	{
	  /* Release the string, if nobody else has used the obstack.  */
	  if (saved_string_obstack_end == notes.next_free) 
	    obstack_free (&notes, string);
	}

      /* At least for now, stabs in a special stab section are always
	 output as 12 byte blocks of information.  */
      p = frag_more (8);
      md_number_to_chars (p, (valueT) stroff, 4);
      md_number_to_chars (p + 4, (valueT) type, 1);
      md_number_to_chars (p + 5, (valueT) other, 1);
      md_number_to_chars (p + 6, (valueT) desc, 2);

      if (what == 's' || what == 'n')
	{
	  /* Pick up the value from the input line.  */
	  cons (4);
	  input_line_pointer--;
	}
      else
	{
	  const char *fake;
	  symbolS *symbol;
	  expressionS exp;

	  /* Arrange for a value representing the current location.  */
	  fake = FAKE_LABEL_NAME;
	  symbol = symbol_new (fake, saved_seg, dot, saved_frag);

	  exp.X_op = O_symbol;
	  exp.X_add_symbol = symbol;
	  exp.X_add_number = 0;

	  emit_expr (&exp, 4);
	}

#ifdef OBJ_PROCESS_STAB
      OBJ_PROCESS_STAB (seg, what, string, type, other, desc);
#endif

      subseg_set (saved_seg, saved_subseg);
    }
  else
    {
#ifdef OBJ_PROCESS_STAB
      OBJ_PROCESS_STAB (0, what, string, type, other, desc);
#else
      abort ();
#endif
    }

  demand_empty_rest_of_line ();
}

/* Regular stab directive.  */

void
s_stab (what)
     int what;
{
  s_stab_generic (what, STAB_SECTION_NAME, STAB_STRING_SECTION_NAME);
}

/* "Extended stabs", used in Solaris only now.  */

void
s_xstab (what)
     int what;
{
  int length;
  char *stab_secname, *stabstr_secname;
  static char *saved_secname, *saved_strsecname;

  /* @@ MEMORY LEAK: This allocates a copy of the string, but in most
     cases it will be the same string, so we could release the storage
     back to the obstack it came from.  */
  stab_secname = demand_copy_C_string (&length);
  SKIP_WHITESPACE ();
  if (*input_line_pointer == ',')
    input_line_pointer++;
  else
    {
      as_bad (_("comma missing in .xstabs"));
      ignore_rest_of_line ();
      return;
    }

  /* To get the name of the stab string section, simply add "str" to
     the stab section name.  */
  if (saved_secname == 0 || strcmp (saved_secname, stab_secname))
    {
      stabstr_secname = (char *) xmalloc (strlen (stab_secname) + 4);
      strcpy (stabstr_secname, stab_secname);
      strcat (stabstr_secname, "str");
      if (saved_secname)
	{
	  free (saved_secname);
	  free (saved_strsecname);
	}
      saved_secname = stab_secname;
      saved_strsecname = stabstr_secname;
    }
  s_stab_generic (what, saved_secname, saved_strsecname);
}

#ifdef S_SET_DESC

/* Frob invented at RMS' request. Set the n_desc of a symbol.  */

void
s_desc (ignore)
     int ignore ATTRIBUTE_UNUSED;
{
  char *name;
  char c;
  char *p;
  symbolS *symbolP;
  int temp;

  name = input_line_pointer;
  c = get_symbol_end ();
  p = input_line_pointer;
  *p = c;
  SKIP_WHITESPACE ();
  if (*input_line_pointer != ',')
    {
      *p = 0;
      as_bad (_("Expected comma after name \"%s\""), name);
      *p = c;
      ignore_rest_of_line ();
    }
  else
    {
      input_line_pointer++;
      temp = get_absolute_expression ();
      *p = 0;
      symbolP = symbol_find_or_make (name);
      *p = c;
      S_SET_DESC (symbolP, temp);
    }
  demand_empty_rest_of_line ();
}				/* s_desc() */

#endif /* defined (S_SET_DESC) */

/* Generate stabs debugging information to denote the main source file.  */

void
stabs_generate_asm_file ()
{
  char *file;
  unsigned int lineno;

  as_where (&file, &lineno);
  generate_asm_file (N_SO, file);
}

/* Generate stabs debugging information to denote the source file.
   TYPE is one of N_SO, N_SOL.  */

static void
generate_asm_file (type, file)
     int type;
     char *file;
{
  static char *last_file;
  static int label_count;
  char *hold;
  char sym[30];
  char *buf;
  char *tmp = file;
  char *endp = file + strlen (file);
  char *bufp = buf;

  if (last_file != NULL
      && strcmp (last_file, file) == 0)
    return;

  /* Rather than try to do this in some efficient fashion, we just
     generate a string and then parse it again.  That lets us use the
     existing stabs hook, which expect to see a string, rather than
     inventing new ones.  */
  hold = input_line_pointer;

  sprintf (sym, "%sF%d", FAKE_LABEL_NAME, label_count);
  ++label_count;

  /* Allocate enough space for the file name (possibly extended with
     doubled up backslashes), the symbol name, and the other characters
     that make up a stabs file directive.  */
  bufp = buf = xmalloc (2 * strlen (file) + strlen (sym) + 12);

  *bufp++ = '"';

  while (tmp < endp)
    {
      char *bslash = strchr (tmp, '\\');
      int len = (bslash ? (bslash - tmp + 1) : strlen (tmp));

      /* Double all backslashes, since demand_copy_C_string (used by
	 s_stab to extract the part in quotes) will try to replace them as
	 escape sequences.  backslash may appear in a filespec.  */
      strncpy (bufp, tmp, len);

      tmp += len;
      bufp += len;

      if (bslash != NULL)
	*bufp++ = '\\';
    }

  sprintf (bufp, "\",%d,0,0,%s\n", type, sym);

  input_line_pointer = buf;
  s_stab ('s');
  colon (sym);

  if (last_file != NULL)
    free (last_file);
  last_file = xstrdup (file);

  free (buf);

  input_line_pointer = hold;
}

/* Generate stabs debugging information for the current line.  This is
   used to produce debugging information for an assembler file.  */

void
stabs_generate_asm_lineno ()
{
  static int label_count;
  char *hold;
  char *file;
  unsigned int lineno;
  char *buf;
  char sym[30];

  /* Let the world know that we are in the middle of generating a
     piece of stabs line debugging information.  */
  outputting_stabs_line_debug = 1;

  /* Rather than try to do this in some efficient fashion, we just
     generate a string and then parse it again.  That lets us use the
     existing stabs hook, which expect to see a string, rather than
     inventing new ones.  */

  hold = input_line_pointer;

  as_where (&file, &lineno);

  generate_asm_file (N_SOL, file);

  sprintf (sym, "%sL%d", FAKE_LABEL_NAME, label_count);
  ++label_count;

  if (in_dot_func_p)
    {
      buf = (char *) alloca (100 + strlen (current_function_label));
      sprintf (buf, "%d,0,%d,%s-%s\n", N_SLINE, lineno,
	       sym, current_function_label);
    }
  else
    {
      buf = (char *) alloca (100);
      sprintf (buf, "%d,0,%d,%s\n", N_SLINE, lineno, sym);
    }
  input_line_pointer = buf;
  s_stab ('n');
  colon (sym);

  input_line_pointer = hold;
  outputting_stabs_line_debug = 0;
}

/* Emit a function stab.
   All assembler functions are assumed to have return type `void'.  */

void
stabs_generate_asm_func (funcname, startlabname)
     const char *funcname;
     const char *startlabname;
{
  static int void_emitted_p;
  char *hold = input_line_pointer;
  char *buf;
  char *file;
  unsigned int lineno;

  if (! void_emitted_p)
    {
      input_line_pointer = "\"void:t1=1\",128,0,0,0";
      s_stab ('s');
      void_emitted_p = 1;
    }

  as_where (&file, &lineno);
  asprintf (&buf, "\"%s:F1\",%d,0,%d,%s",
	    funcname, N_FUN, lineno + 1, startlabname);
  input_line_pointer = buf;
  s_stab ('s');
  free (buf);

  input_line_pointer = hold;
  current_function_label = xstrdup (startlabname);
  in_dot_func_p = 1;
}

/* Emit a stab to record the end of a function.  */

void
stabs_generate_asm_endfunc (funcname, startlabname)
     const char *funcname ATTRIBUTE_UNUSED;
     const char *startlabname;
{
  static int label_count;
  char *hold = input_line_pointer;
  char *buf;
  char sym[30];

  sprintf (sym, "%sendfunc%d", FAKE_LABEL_NAME, label_count);
  ++label_count;
  colon (sym);

  asprintf (&buf, "\"\",%d,0,0,%s-%s", N_FUN, sym, startlabname);
  input_line_pointer = buf;
  s_stab ('s');
  free (buf);

  input_line_pointer = hold;
  in_dot_func_p = 0;
  current_function_label = NULL;
}