gasp.c

来自「基于4个mips核的noc设计」· C语言 代码 · 共 3,135 行 · 第 1/5 页

	symbol t;
	idx = level_1 (idx + 1, string, lhs);
	lhs->value = -lhs->value;
	t = lhs->add_symbol;
	lhs->add_symbol = lhs->sub_symbol;
	lhs->sub_symbol = t;
	break;
      }
    case '(':
      idx++;
      idx = level_5 (sb_skip_white (idx, string), string, lhs);
      if (string->ptr[idx] != ')')
	ERROR ((stderr, _("misplaced closing parens.\n")));
      else
	idx++;
      break;
    default:
      idx = level_0 (idx, string, lhs);
      break;
    }
  return sb_skip_white (idx, string);
}

static int
level_2 (idx, string, lhs)
     int idx;
     sb *string;
     exp_t *lhs;
{
  exp_t rhs;

  idx = level_1 (idx, string, lhs);

  while (idx < string->len && (string->ptr[idx] == '*'
			       || string->ptr[idx] == '/'))
    {
      char op = string->ptr[idx++];
      idx = level_1 (idx, string, &rhs);
      switch (op)
	{
	case '*':
	  checkconst ('*', lhs);
	  checkconst ('*', &rhs);
	  lhs->value *= rhs.value;
	  break;
	case '/':
	  checkconst ('/', lhs);
	  checkconst ('/', &rhs);
	  if (rhs.value == 0)
	    ERROR ((stderr, _("attempt to divide by zero.\n")));
	  else
	    lhs->value /= rhs.value;
	  break;
	}
    }
  return sb_skip_white (idx, string);
}

static int
level_3 (idx, string, lhs)
     int idx;
     sb *string;
     exp_t *lhs;
{
  exp_t rhs;

  idx = level_2 (idx, string, lhs);

  while (idx < string->len
	 && (string->ptr[idx] == '+'
	     || string->ptr[idx] == '-'))
    {
      char op = string->ptr[idx++];
      idx = level_2 (idx, string, &rhs);
      switch (op)
	{
	case '+':
	  lhs->value += rhs.value;
	  if (lhs->add_symbol.name && rhs.add_symbol.name)
	    {
	      ERROR ((stderr, _("can't add two relocatable expressions\n")));
	    }
	  /* Change nn+symbol to symbol + nn.  */
	  if (rhs.add_symbol.name)
	    {
	      lhs->add_symbol = rhs.add_symbol;
	    }
	  break;
	case '-':
	  lhs->value -= rhs.value;
	  lhs->sub_symbol = rhs.add_symbol;
	  break;
	}
    }
  return sb_skip_white (idx, string);
}

static int
level_4 (idx, string, lhs)
     int idx;
     sb *string;
     exp_t *lhs;
{
  exp_t rhs;

  idx = level_3 (idx, string, lhs);

  while (idx < string->len &&
	 string->ptr[idx] == '&')
    {
      char op = string->ptr[idx++];
      idx = level_3 (idx, string, &rhs);
      switch (op)
	{
	case '&':
	  checkconst ('&', lhs);
	  checkconst ('&', &rhs);
	  lhs->value &= rhs.value;
	  break;
	}
    }
  return sb_skip_white (idx, string);
}

static int
level_5 (idx, string, lhs)
     int idx;
     sb *string;
     exp_t *lhs;
{
  exp_t rhs;

  idx = level_4 (idx, string, lhs);

  while (idx < string->len
	 && (string->ptr[idx] == '|' || string->ptr[idx] == '~'))
    {
      char op = string->ptr[idx++];
      idx = level_4 (idx, string, &rhs);
      switch (op)
	{
	case '|':
	  checkconst ('|', lhs);
	  checkconst ('|', &rhs);
	  lhs->value |= rhs.value;
	  break;
	case '~':
	  checkconst ('~', lhs);
	  checkconst ('~', &rhs);
	  lhs->value ^= rhs.value;
	  break;
	}
    }
  return sb_skip_white (idx, string);
}

/* Parse the expression at offset idx into string, fill up res with
   the result.  Return the index of the first char past the
   expression.  */

static int
exp_parse (idx, string, res)
     int idx;
     sb *string;
     exp_t *res;
{
  return level_5 (sb_skip_white (idx, string), string, res);
}

/* Turn the expression at exp into text and glue it onto the end of
   string.  */

static void
exp_string (exp, string)
     exp_t *exp;
     sb *string;
{
  int np = 0;
  int ad = 0;
  sb_reset (string);

  if (exp->add_symbol.len)
    {
      sb_add_buffer (string, exp->add_symbol.name, exp->add_symbol.len);
      np = 1;
      ad = 1;
    }
  if (exp->value)
    {
      char buf[20];
      if (np)
	sb_add_char (string, '+');
      sprintf (buf, "%d", exp->value);
      sb_add_string (string, buf);
      np = 1;
      ad = 1;
    }
  if (exp->sub_symbol.len)
    {
      sb_add_char (string, '-');
      sb_add_buffer (string, exp->add_symbol.name, exp->add_symbol.len);
      np = 0;
      ad = 1;
    }

  if (!ad)
    sb_add_char (string, '0');
}

/* Parse the expression at offset idx into sb in.  Return the value in
   val.  If the expression is not constant, give ERROR emsg.  Return
   the index of the first character past the end of the expression.  */

static int
exp_get_abs (emsg, idx, in, val)
     const char *emsg;
     int idx;
     sb *in;
     int *val;
{
  exp_t res;
  idx = exp_parse (idx, in, &res);
  if (res.add_symbol.len || res.sub_symbol.len)
    ERROR ((stderr, "%s", emsg));
  *val = res.value;
  return idx;
}

/* Current label parsed from line.  */
sb label;

/* Hash table for all assigned variables.  */
hash_table assign_hash_table;

/* Hash table for keyword.  */
hash_table keyword_hash_table;

/* Hash table for eq variables.  */
hash_table vars;

#define in_comment ';'

#if 0
static void
strip_comments (out)
     sb *out;
{
  char *s = out->ptr;
  int i = 0;
  for (i = 0; i < out->len; i++)
    {
      if (ISCOMMENTCHAR (s[i]))
	{
	  out->len = i;
	  return;
	}
    }
}
#endif

/* Push back character ch so that it can be read again.  */

static void
unget (ch)
     int ch;
{
  if (ch == '\n')
    {
      sp->linecount--;
    }
  if (sp->pushback_index)
    sp->pushback_index--;
  else
    sb_add_char (&sp->pushback, ch);
}

/* Push the sb ptr onto the include stack, with the given name, type
   and index.  */

static void
include_buf (name, ptr, type, index)
     sb *name;
     sb *ptr;
     include_type type;
     int index;
{
  sp++;
  if (sp - include_stack >= MAX_INCLUDES)
    FATAL ((stderr, _("unreasonable nesting.\n")));
  sb_new (&sp->name);
  sb_add_sb (&sp->name, name);
  sp->handle = 0;
  sp->linecount = 1;
  sp->pushback_index = 0;
  sp->type = type;
  sp->index = index;
  sb_new (&sp->pushback);
  sb_add_sb (&sp->pushback, ptr);
}

/* Used in ERROR messages, print info on where the include stack is
   onto file.  */

static void
include_print_where_line (file)
     FILE *file;
{
  struct include_stack *p = include_stack + 1;

  while (p <= sp)
    {
      fprintf (file, "%s:%d ", sb_name (&p->name), p->linecount - 1);
      p++;
    }
}

/* Used in listings, print the line number onto file.  */

static void
include_print_line (file)
     FILE *file;
{
  int n;
  struct include_stack *p = include_stack + 1;

  n = fprintf (file, "%4d", p->linecount);
  p++;
  while (p <= sp)
    {
      n += fprintf (file, ".%d", p->linecount);
      p++;
    }
  while (n < 8 * 3)
    {
      fprintf (file, " ");
      n++;
    }
}

/* Read a line from the top of the include stack into sb in.  */

static int
get_line (in)
     sb *in;
{
  int online = 0;
  int more = 1;

  if (copysource)
    {
      putc (comment_char, outfile);
      if (print_line_number)
	include_print_line (outfile);
    }

  while (1)
    {
      int ch = get ();

      while (ch == '\r')
	ch = get ();

      if (ch == EOF)
	{
	  if (online)
	    {
	      WARNING ((stderr, _("End of file not at start of line.\n")));
	      if (copysource)
		putc ('\n', outfile);
	      ch = '\n';
	    }
	  else
	    more = 0;
	  break;
	}

      if (copysource)
	{
	  putc (ch, outfile);
	}

      if (ch == '\n')
	{
	  ch = get ();
	  online = 0;
	  if (ch == '+')
	    {
	      /* Continued line.  */
	      if (copysource)
		{
		  putc (comment_char, outfile);
		  putc ('+', outfile);
		}
	      ch = get ();
	    }
	  else
	    {
	      if (ch != EOF)
		unget (ch);
	      break;
	    }
	}
      else
	{
	  sb_add_char (in, ch);
	}
      online++;
    }

  return more;
}

/* Find a label from sb in and put it in out.  */

static int
grab_label (in, out)
     sb *in;
     sb *out;
{
  int i = 0;
  sb_reset (out);
  if (ISFIRSTCHAR (in->ptr[i]) || in->ptr[i] == '\\')
    {
      sb_add_char (out, in->ptr[i]);
      i++;
      while ((ISNEXTCHAR (in->ptr[i])
	      || in->ptr[i] == '\\'
	      || in->ptr[i] == '&')
	     && i < in->len)
	{
	  sb_add_char (out, in->ptr[i]);
	  i++;
	}
    }
  return i;
}

/* Find all strange base stuff and turn into decimal.  Also
   find all the other numbers and convert them from the default radix.  */

static void
change_base (idx, in, out)
     int idx;
     sb *in;
     sb *out;
{
  char buffer[20];

  while (idx < in->len)
    {
      if (in->ptr[idx] == '\\'
	  && idx + 1 < in->len
	  && in->ptr[idx + 1] == '(')
	{
	  idx += 2;
	  while (idx < in->len
		 && in->ptr[idx] != ')')
	    {
	      sb_add_char (out, in->ptr[idx]);
	      idx++;
	    }
	  if (idx < in->len)
	    idx++;
	}
      else if (idx < in->len - 1 && in->ptr[idx + 1] == '\'' && ! mri)
	{
	  int base;
	  int value;
	  switch (in->ptr[idx])
	    {
	    case 'b':
	    case 'B':
	      base = 2;
	      break;
	    case 'q':
	    case 'Q':
	      base = 8;
	      break;
	    case 'h':
	    case 'H':
	      base = 16;
	      break;
	    case 'd':
	    case 'D':
	      base = 10;
	      break;
	    default:
	      ERROR ((stderr, _("Illegal base character %c.\n"), in->ptr[idx]));
	      base = 10;
	      break;
	    }

	  idx = sb_strtol (idx + 2, in, base, &value);
	  sprintf (buffer, "%d", value);
	  sb_add_string (out, buffer);
	}
      else if (ISFIRSTCHAR (in->ptr[idx]))
	{
	  /* Copy entire names through quickly.  */
	  sb_add_char (out, in->ptr[idx]);
	  idx++;
	  while (idx < in->len && ISNEXTCHAR (in->ptr[idx]))
	    {
	      sb_add_char (out, in->ptr[idx]);
	      idx++;
	    }
	}
      else if (isdigit ((unsigned char) in->ptr[idx]))
	{
	  int value;
	  /* All numbers must start with a digit, let's chew it and
	     spit out decimal.  */
	  idx = sb_strtol (idx, in, radix, &value);
	  sprintf (buffer, "%d", value);
	  sb_add_string (out, buffer);

	  /* Skip all undigsested letters.  */
	  while (idx < in->len && ISNEXTCHAR (in->ptr[idx]))
	    {
	      sb_add_char (out, in->ptr[idx]);
	      idx++;
	    }
	}
      else if (in->ptr[idx] == '"' || in->ptr[idx] == '\'')
	{
	  char tchar = in->ptr[idx];
	  /* Copy entire names through quickly.  */
	  sb_add_char (out, in->ptr[idx]);
	  idx++;
	  while (idx < in->len && in->ptr[idx] != tchar)
	    {
	      sb_add_char (out, in->ptr[idx]);
	      idx++;
	    }
	}
      else
	{
	  /* Nothing special, just pass it through.  */
	  sb_add_char (out, in->ptr[idx]);
	  idx++;
	}
    }

}

/* .end  */

static void
do_end (in)
     sb *in;
{
  had_end = 1;
  if (mri)
    fprintf (outfile, "%s\n", sb_name (in));
}

/* .assign  */

static void
do_assign (again, idx, in)
     int again;
     int idx;
     sb *in;
{
  /* Stick label in symbol table with following value.  */
  exp_t e;
  sb acc;

  sb_new (&acc);
  idx = exp_parse (idx, in, &e);
  exp_string (&e, &acc);
  hash_add_to_string_table (&assign_hash_table, &label, &acc, again);
  sb_kill (&acc);
}

/* .radix [b|q|d|h]  */

static void
do_radix (ptr)
     sb *ptr;
{
  int idx = sb_skip_white (0, ptr);
  switch (ptr->ptr[idx])
    {
    case 'B':
    case 'b':
      radix = 2;
      break;
    case 'q':
    case 'Q':
      radix = 8;
      break;
    case 'd':
    case 'D':
      radix = 10;
      break;
    case 'h':
    case 'H':
      radix = 16;
      break;
    default:
      ERROR ((stderr, _("radix is %c must be one of b, q, d or h"), radix));
    }
}

/* Parse off a .b, .w or .l.  */

static int
get_opsize (idx, in, size)
     int idx;
     sb *in;
     int *size;
{
  *size = 4;
  if (in->ptr[idx] == '.')
    {
      idx++;
    }
  switch (in->ptr[idx])
    {
    case 'b':
    case 'B':
      *size = 1;
      break;
    case 'w':
    case 'W':
      *size = 2;