lex.c

gcc-2.95.3 Linux下最常用的C编译器

	    {
	      /* #ident.  The pedantic warning is now in cccp.c.  */

	      /* Here we have just seen `#ident '.
		 A string constant should follow.  */

	      while (c == ' ' || c == '\t')
		c = getlc (finput);

	      /* If no argument, ignore the line.  */
	      if (c == '\n')
		return c;

	      ungetc (c, finput);
	      token = yylex ();
	      if (token != STRING
		  || TREE_CODE (yylval.ttype) != STRING_CST)
		{
		  error ("invalid #ident");
		  goto skipline;
		}

	      if (!flag_no_ident)
		{
#ifdef ASM_OUTPUT_IDENT
		  extern FILE *asm_out_file;
		  ASM_OUTPUT_IDENT (asm_out_file, TREE_STRING_POINTER (yylval.ttype));
#endif
		}

	      /* Skip the rest of this line.  */
	      goto skipline;
	    }
	}
#endif

      error ("undefined or invalid # directive");
      goto skipline;
    }

linenum:
  /* Here we have either `#line' or `# <nonletter>'.
     In either case, it should be a line number; a digit should follow.  */

  while (c == ' ' || c == '\t')
    c = getlc (finput);

  /* If the # is the only nonwhite char on the line,
     just ignore it.  Check the new newline.  */
  if (c == '\n')
    return c;

  /* Something follows the #; read a token.  */

  if (ISDIGIT(c))
    {
      int old_lineno = lineno;
      int used_up = 0;
      int l = 0;
      extern struct obstack permanent_obstack;

      do
	{
	  l = l * 10 + (c - '0'); /* FIXME Not portable */
	  c = getlc(finput);
	} while (ISDIGIT(c));
      /* subtract one, because it is the following line that
	 gets the specified number */

      l--;

      /* Is this the last nonwhite stuff on the line?  */
      c = getlc (finput);
      while (c == ' ' || c == '\t')
	c = getlc (finput);
      if (c == '\n')
	{
	  /* No more: store the line number and check following line.  */
	  lineno = l;
	  return c;
	}

      /* More follows: it must be a string constant (filename).  */

      /* Read the string constant, but don't treat \ as special.  */
      ignore_escape_flag = 1;
      ignore_escape_flag = 0;

      if (c != '\"')
	{
	  error ("invalid #line");
	  goto skipline;
	}

      for (;;)
	{
	  c = getc (finput);
	  if (c == EOF || c == '\n')
	    {
	      error ("invalid #line");
	      return c;
	    }
	  if (c == '\"')
	    {
	      obstack_1grow(&permanent_obstack, 0);
	      input_filename = obstack_finish (&permanent_obstack);
	      break;
	    }
	  obstack_1grow(&permanent_obstack, c);
	}

      lineno = l;

      /* Each change of file name
	 reinitializes whether we are now in a system header.  */
      in_system_header = 0;

      if (main_input_filename == 0)
	main_input_filename = input_filename;

      /* Is this the last nonwhite stuff on the line?  */
      c = getlc (finput);
      while (c == ' ' || c == '\t')
	c = getlc (finput);
      if (c == '\n')
	return c;

      used_up = 0;

      /* `1' after file name means entering new file.
	 `2' after file name means just left a file.  */

      if (ISDIGIT (c))
	{
	  if (c == '1')
	    {
	      /* Pushing to a new file.  */
	      struct file_stack *p
		= (struct file_stack *) xmalloc (sizeof (struct file_stack));
	      input_file_stack->line = old_lineno;
	      p->next = input_file_stack;
	      p->name = input_filename;
	      input_file_stack = p;
	      input_file_stack_tick++;
#ifdef DWARF_DEBUGGING_INFO
	      if (debug_info_level == DINFO_LEVEL_VERBOSE
		  && write_symbols == DWARF_DEBUG)
		dwarfout_start_new_source_file (input_filename);
#endif /* DWARF_DEBUGGING_INFO */

	      used_up = 1;
	    }
	  else if (c == '2')
	    {
	      /* Popping out of a file.  */
	      if (input_file_stack->next)
		{
		  struct file_stack *p = input_file_stack;
		  input_file_stack = p->next;
		  free (p);
		  input_file_stack_tick++;
#ifdef DWARF_DEBUGGING_INFO
		  if (debug_info_level == DINFO_LEVEL_VERBOSE
		      && write_symbols == DWARF_DEBUG)
		    dwarfout_resume_previous_source_file (input_file_stack->line);
#endif /* DWARF_DEBUGGING_INFO */
		}
	      else
		error ("#-lines for entering and leaving files don't match");

	      used_up = 1;
	    }
	}

      /* If we have handled a `1' or a `2',
	 see if there is another number to read.  */
      if (used_up)
	{
	  /* Is this the last nonwhite stuff on the line?  */
	  c = getlc (finput);
	  while (c == ' ' || c == '\t')
	    c = getlc (finput);
	  if (c == '\n')
	    return c;
	  used_up = 0;
	}

      /* `3' after file name means this is a system header file.  */

      if (c == '3')
	in_system_header = 1;
    }
  else
    error ("invalid #-line");

  /* skip the rest of this line.  */
 skipline:
  while (c != '\n' && c != EOF)
    c = getc (finput);
  return c;
}


tree
get_chill_filename ()
{
  return (build_chill_string (
            strlen (input_filename) + 1,  /* +1 to get a zero terminated string */
	      input_filename));
}

tree
get_chill_linenumber ()
{
  return build_int_2 ((HOST_WIDE_INT)lineno, 0);
}


/* Assuming '/' and '*' have been read, skip until we've
   read the terminating '*' and '/'. */

static void
skip_c_comment ()
{
  int c = input();
  int start_line = lineno;

  inside_c_comment++;
  for (;;)
    if (c == EOF)
      {
	error_with_file_and_line (input_filename, start_line,
				  "unterminated comment");
	break;
      }
    else if (c != '*')
      c = input();
    else if ((c = input ()) == '/')
      break;
  inside_c_comment--;
}


/* Assuming "--" has been read, skip until '\n'. */

static void
skip_line_comment ()
{
  for (;;)
    {
      int c = input ();

      if (c == EOF)
	return;
      if (c == '\n')
	break;
    }
  unput ('\n');
}


static int
skip_whitespace ()
{
  for (;;)
    {
      int c = input ();

      if (c == EOF)
	return c;
      if (c == ' ' || c == '\t' || c == '\r' || c == '\n' || c == '\v')
	continue;
      if (c == '/')
	{
	  c = input ();
	  if (c == '*')
	    {
	      skip_c_comment ();
	      continue;
	    }
	  else
	    {
	      unput (c);
	      return '/';
	    }
	}
      if (c == '-')
	{
	  c = input ();
	  if (c == '-')
	    {
	      skip_line_comment ();
	      continue;
	    }
	  else
	    {
	      unput (c);
	      return '-';
	    }
	}
      return c;
    }
}

/*
 * avoid recursive calls to yylex to parse the ' = digits' or
 * ' = SYNvalue' which are supposed to follow certain compiler
 * directives.  Read the input stream, and return the value parsed.
 */
         /* FIXME: overflow check in here */
         /* FIXME: check for EOF around here */
static tree
equal_number ()
{
  int      c, result;
  char    *tokenbuf;
  char    *cursor;
  tree     retval = integer_zero_node;
  
  c = skip_whitespace();
  if ((char)c != '=')
    {
      if (pass == 2)
	error ("missing `=' in compiler directive");
      return integer_zero_node;
    }
  c = skip_whitespace();

  /* collect token into tokenbuf for later analysis */
  while (TRUE)
    {
      if (ISSPACE (c) || c == '<')
	break;
      obstack_1grow (&temporary_obstack, c);
      c = input ();
    }
  unput (c);             /* put uninteresting char back */
  obstack_1grow (&temporary_obstack, '\0');        /* terminate token */
  tokenbuf = obstack_finish (&temporary_obstack);
  maybe_downcase (tokenbuf);

  if (*tokenbuf == '-')
    /* will fail in the next test */
    result = BITSTRING;
  else if (maybe_number (tokenbuf))
    {
      if (pass == 1)
	return integer_zero_node;
      push_obstacks_nochange ();
      end_temporary_allocation ();
      yylval.ttype = convert_integer (tokenbuf);
      tokenbuf = 0;  /* Was freed by convert_integer. */
      result = yylval.ttype ? NUMBER : 0;
      pop_obstacks ();
    }
  else
    result = 0;
  
  if (result  == NUMBER)
    {
      retval = yylval.ttype;
    }
  else if (result == BITSTRING)
    {
      if (pass == 1)
        error ("invalid value follows `=' in compiler directive");
      goto finish;
    }
  else /* not a number */
    {
      cursor = tokenbuf;
      c = *cursor;
      if (!ISALPHA (c) && c != '_')
	{
	  if (pass == 1)
	    error ("invalid value follows `=' in compiler directive");
	  goto finish;
	}

      for (cursor = &tokenbuf[1]; *cursor != '\0'; cursor++)
	if (ISALPHA ((unsigned char) *cursor) || *cursor == '_' ||
	    ISDIGIT (*cursor))
	  continue;
	else
	  {
	    if (pass == 1)
	      error ("invalid `%c' character in name", *cursor);
	    goto finish;
	  }
      if (pass == 1)
	goto finish;
      else
	{
	  tree value = lookup_name (get_identifier (tokenbuf));
	  if (value == NULL_TREE
	      || TREE_CODE (value) != CONST_DECL
	      || TREE_CODE (DECL_INITIAL (value)) != INTEGER_CST)
	    {
	      if (pass == 2)
		error ("`%s' not integer constant synonym ",
		       tokenbuf);
	      goto finish;
	    }
	  obstack_free (&temporary_obstack, tokenbuf);
	  tokenbuf = 0;
	  push_obstacks_nochange ();
	  end_temporary_allocation ();
	  retval = convert (chill_taskingcode_type_node, DECL_INITIAL (value));
	  pop_obstacks ();
	}
    }

  /* check the value */
  if (TREE_CODE (retval) != INTEGER_CST)
    {
      if (pass == 2)
	error ("invalid value follows `=' in compiler directive");
    }
  else if (TREE_INT_CST_HIGH (retval) != 0 ||
	   TREE_INT_CST_LOW (retval) > TREE_INT_CST_LOW (TYPE_MAX_VALUE (chill_unsigned_type_node)))
    {
      if (pass == 2)
	error ("value out of range in compiler directive");
    }
 finish:
  if (tokenbuf)
    obstack_free (&temporary_obstack, tokenbuf);
  return retval;
}

/*
 * add a possible grant-file path to the list
 */
void
register_seize_path (path)
     char *path;
{
  int          pathlen = strlen (path);
  char        *new_path = (char *)xmalloc (pathlen + 1);
  STRING_LIST *pl     = (STRING_LIST *)xmalloc (sizeof (STRING_LIST));
    
  /* strip off trailing slash if any */
  if (path[pathlen - 1] == '/')
    pathlen--;

  memcpy (new_path, path, pathlen);
  pl->str  = new_path;
  pl->next = seize_path_list;
  seize_path_list = pl;
}


/* Used by decode_decl to indicate that a <> use_seize_file NAME <>
   directive has been written to the grantfile. */

void
mark_use_seizefile_written (name)
     tree name;
{
  tree node;

  for (node = files_to_seize;  node != NULL_TREE; node = TREE_CHAIN (node))
    if (TREE_VALUE (node) == name)
      {
	TREE_PURPOSE (node) = integer_one_node;
	break;
      }
}


static int
yywrap ()
{
  extern char *chill_real_input_filename;

  close_input_file (input_filename);

  use_seizefile_name = NULL_TREE;

  if (next_file_to_seize && !grant_only_flag)
    {
      FILE *grt_in = NULL;
      char *seizefile_name_chars
	= IDENTIFIER_POINTER (TREE_VALUE (next_file_to_seize));

      /* find a seize file, open it.  If it's not at the path the
       * user gave us, and that path contains no slashes, look on
       * the seize_file paths, specified by the '-I' options.
       */     
      grt_in = fopen (seizefile_name_chars, "r");
      if (grt_in == NULL 
	  && strchr (seizefile_name_chars, '/') == NULL)
	{
	  STRING_LIST *plp;
	  char      *path;

	  for (plp = seize_path_list; plp != NULL; plp = plp->next)
	    {
	      path = (char *)xmalloc (strlen (seizefile_name_chars)
				      + strlen (plp->str) + 2);

	      sprintf (path, "%s/%s", plp->str, seizefile_name_chars);
	      grt_in = fopen (path, "r");
	      if (grt_in == NULL)
		free (path);
	      else
		{
		  seizefile_name_chars = path;
		  break;
		}
	    }
	}

      if (grt_in == NULL)
	pfatal_with_name (seizefile_name_chars);

      finput = grt_in;
      input_filename = seizefile_name_chars;

      lineno = 0;
      current_seizefile_name = TREE_VALUE (next_file_to_seize);

      next_file_to_seize = TREE_CHAIN (next_file_to_seize);

      saw_eof = 0;
      return 0;
    }

  if (pass == 1)
    {
      next_file_to_seize = files_to_seize;
      current_seizefile_name = NULL_TREE;

      if (strcmp (main_input_filename, "stdin"))
	finput = fopen (chill_real_input_filename, "r");
      else
	finput = stdin;
      if (finput == NULL)
	{
	  error ("can't reopen %s", chill_real_input_filename);
	  return 1;
	}
      input_filename = main_input_filename;
      ch_lex_init ();
      lineno = 0;
      /* Read a line directive if there is one.  */
      ungetc (check_newline (), finput);
      starting_pass_2 = 1;
      saw_eof = 0;
      if (module_number == 0)
	warning ("no modules seen");
      return 0;
    }
  return 1;
}