1750a.c

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      return 1;
    default:
      return 0;
    }
}

int
next_cc_user_is_unsigned (insn)
     rtx insn;
{
  if ( !(insn = next_cc0_user (insn)))
    abort ();
  else if (GET_CODE (insn) == JUMP_INSN
	   && GET_CODE (PATTERN (insn)) == SET
	   && GET_CODE (SET_SRC (PATTERN (insn))) == IF_THEN_ELSE)
    return unsigned_comparison_operator (XEXP (SET_SRC (PATTERN (insn)), 0));
  else if (GET_CODE (insn) == INSN
	   && GET_CODE (PATTERN (insn)) == SET)
    return unsigned_comparison_operator (SET_SRC (PATTERN (insn)));
  else
    abort ();
}


static int addr_inc;

/* A C compound statement to output to stdio stream STREAM the
   assembler syntax for an instruction operand X.  X is an RTL
   expression.

   CODE is a value that can be used to specify one of several ways
   of printing the operand.  It is used when identical operands
   must be printed differently depending on the context.  CODE
   comes from the `%' specification that was used to request
   printing of the operand.  If the specification was just `%DIGIT'
   then CODE is 0; if the specification was `%LTR DIGIT' then CODE
   is the ASCII code for LTR.

   If X is a register, this macro should print the register's name.
   The names can be found in an array `reg_names' whose type is
   `char *[]'.  `reg_names' is initialized from `REGISTER_NAMES'.

   When the machine description has a specification `%PUNCT' (a `%'
   followed by a punctuation character), this macro is called with
   a null pointer for X and the punctuation character for CODE.

   The 1750 specific codes are:
   'J' for the negative of a constant
   'Q' for printing addresses in B mode syntax
   'd' for the second register in a pair
   't' for the third register in a triple 
   'b' for the bit number (using 1750 test bit convention)
   'B' for the bit number of the 1's complement (for bit clear)
   'w' for int - 16
*/

print_operand (file, x, letter)
     FILE *file;
     rtx x;
     int letter;
{
  switch (GET_CODE (x))
    {
    case REG:
      if (letter == 'd')
	fprintf (file, "%d", REGNO (x) + 1);
      else if (letter == 't')
	fprintf (file, "%d", REGNO (x) + 2);
      else
	fprintf (file, "%d", REGNO (x));
      break;

    case SYMBOL_REF:
      fprintf (file, "%s", XSTR (x, 0));
      if (letter == 'A')
	fprintf (file, "+1");
      break;

    case LABEL_REF:
    case CONST:
    case MEM:
      if (letter == 'Q')
	{
	  rtx inner = XEXP (x, 0);
	  switch (GET_CODE (inner))
	    {
	    case REG:
	      fprintf (file, "r%d,0", REGNO (inner));
	      break;
	    case PLUS:
	      fprintf (file, "r%d,%d", REGNO (XEXP (inner, 0)),
		       INTVAL (XEXP (inner, 1)));
	      break;
	    default:
	      fprintf (file, "[ill Q code=%d]", GET_CODE (inner));
	    }
	}
      else
	{
	  addr_inc = (letter == 'A' ? 1 : 0);
	  output_address (XEXP (x, 0));
	}
      break;

    case CONST_DOUBLE:
/*    {
	double value = get_double (x);
	char fltstr[32];
	sprintf (fltstr, "%lf", value);

	if (letter == 'D' || letter == 'E')
	  {
	    int i, found = 0;
	    for (i = 0; i <= datalbl_ndx; i++)
	      if (strcmp (fltstr, datalbl[i].value) == 0)
		{
		  found = 1;
		  break;
		}
	    if (!found)
	      {
		strcpy (datalbl[i = ++datalbl_ndx].value, fltstr);
		datalbl[i].name = float_label (letter, value);
		datalbl[i].size = (letter == 'E') ? 3 : 2;
		check_section (Konst);
		fprintf (file, "K%s \tdata%s %s ;p_o\n", datalbl[i].name,
			(letter == 'E' ? "ef" : "f"), fltstr);
		check_section (Normal);
	      }
	  }
	else if (letter == 'F' || letter == 'G')
	  {
	    int i, found = 0;
	    for (i = 0; i <= datalbl_ndx; i++)
	      if (strcmp (fltstr, datalbl[i].value) == 0)
		{
		  found = 1;
		  break;
		}
	    if (!found)
	      {
		fprintf (stderr,
		   "float value %lfnot found upon label reference\n", value);
		strcpy (datalbl[i = ++datalbl_ndx].value, fltstr);
		datalbl[i].name = float_label (letter, value);
		datalbl[i].size = (letter == 'G') ? 3 : 2;
		check_section (Konst);
		fprintf (file, "K%s \tdata%s %s ;p_o\n", datalbl[i].name,
			(letter == 'G' ? "ef" : "f"), fltstr);
		check_section (Normal);
	      }
	    fprintf (file, "%s ;P_O 'F'", datalbl[i].name);
	  }
	else
	  fprintf (file, " %s  ;P_O cst_dbl ", fltstr);
      }
 */
      fprintf (file, "%lf", get_double (x));
      break;

    case CONST_INT:
      if (letter == 'J')
	fprintf (file, "%d", -INTVAL (x));
      else if (letter == 'b')
        fprintf (file, "%d", which_bit (INTVAL (x)));
      else if (letter == 'B')
        fprintf (file, "%d", which_bit (~INTVAL (x)));
      else if (letter == 'w')
	fprintf (file, "%d", INTVAL (x) - 16);
      else
	fprintf (file, "%d", INTVAL (x));
      break;

    case CODE_LABEL:
      fprintf (file, "L%d", XINT (x, 3));
      break;

    case CALL:
      fprintf (file, "CALL nargs=%d, func is either '%s' or '%s'",
       XEXP (x, 1), XSTR (XEXP (XEXP (x, 0), 1), 0), XSTR (XEXP (x, 0), 1));
      break;

    case PLUS:
      {
	rtx op0 = XEXP (x, 0), op1 = XEXP (x, 1);
	int op0code = GET_CODE (op0), op1code = GET_CODE (op1);
	if (op1code == CONST_INT)
	  switch (op0code)
	    {
	    case REG:
	      fprintf (file, "%d,r%d  ; p_o_PLUS for REG and CONST_INT",
		       INTVAL (op1), REGNO (op0));
	      break;
	    case SYMBOL_REF:
	      fprintf (file, "%d+%s", INTVAL (op1), XSTR (op0, 0));
	      break;
	    case MEM:
	      fprintf (file, "%d,[mem:", INTVAL (op1));
	      output_address (XEXP (op0, 0));
	      fprintf (file, "] ;P_O plus");
	      break;
	    default:
	      fprintf (file, "p_o_PLUS UFO, code=%d, with CONST=%d",
		       (int) op0code, INTVAL (op1));
	    }
	else if (op1code == SYMBOL_REF && op0code == REG)
	  fprintf (file, "%s,r%d  ; P_O: (plus reg sym)",
		   XSTR (op1, 0), REGNO (op0));
	else
	  fprintf (file, "p_o_+: op0code=%d, op1code=%d", op0code, op1code);
      }
      break;

    default:
      fprintf (file, "p_o_UFO code=%d", GET_CODE (x));
    }

  addr_inc = 0;
}

print_operand_address (file, addr)
     FILE *file;
     rtx addr;
{
  switch (GET_CODE (addr))
    {
    case REG:
      fprintf (file, "%d,r%d ; P_O_A", addr_inc, REGNO (addr));
      break;
    case PLUS:
      {
	register rtx x = XEXP (addr, 0), y = XEXP (addr, 1);
	switch (GET_CODE (x))
	  {
	  case REG:
	    switch (GET_CODE (y))
	      {
	      case CONST:
		output_address (XEXP (y, 0));
		fprintf (file, ",r%d ;P_O_A reg + const expr", REGNO (x));
		break;
	      case CONST_INT:
		fprintf (file, "%d,r%d", INTVAL (y) + addr_inc, REGNO (x));
		break;
	      case SYMBOL_REF:
		fprintf (file, "%s", XSTR (y, 0));
		if (addr_inc)
		  fprintf (file, "+%d", addr_inc);
		fprintf (file, ",r%d  ; P_O_A reg + sym", REGNO (x));
		break;
	      case LABEL_REF:
		output_address (XEXP (y, 0));
		fprintf (file, ",r%d  ; P_O_A reg + label", REGNO (x));
		break;
	      default:
		fprintf (file, "[P_O_A reg%d+UFO code=%d]",
			 REGNO (x), GET_CODE (y));
	      }
	    break;
	  case LABEL_REF:
	    output_address (XEXP (x, 0));
	    break;
	  case SYMBOL_REF:
	    switch (GET_CODE (y))
	      {
	      case CONST_INT:
		fprintf (file, "%d+%s", INTVAL (y) + addr_inc, XSTR (x, 0));
		break;
	      case REG:
		fprintf (file, "%s,r%d ;P_O_A sym + reg",
			 XSTR (x, 0), REGNO (y));
		break;
	      default:
		fprintf (file, "P_O_A sym/lab+UFO[sym=%s,code(y)=%d]",
			 XSTR (x, 0), GET_CODE (y));
	      }
	    break;
	  case CONST:
	    output_address (XEXP (x, 0));
	    if (GET_CODE (y) == REG)
	      fprintf (file, ",r%d ;P_O_A const + reg", REGNO (x));
	    else
	      fprintf (file, "P_O_A const+UFO code(y)=%d]", GET_CODE (y));
	    break;
	  case MEM:
	    output_address (y);
	    fprintf (file, ",[mem:");
	    output_address (XEXP (x, 0));
	    fprintf (file, "] ;P_O_A plus");
	    break;
	  default:
	    fprintf (file, "P_O_A plus op1_UFO[code1=%d,code2=%d]",
		     GET_CODE (x), GET_CODE (y));
	  }
      }
      break;
    case CONST_INT:
      if (INTVAL (addr) < 0x10000 && INTVAL (addr) >= -0x10000)
	fprintf (file, "%d ; p_o_a const addr?!", INTVAL (addr));
      else
	{
	  fprintf (file, "[p_o_a=ILLEGAL_CONST]");
	  output_addr_const (file, addr);
	}
      break;
    case LABEL_REF:
    case SYMBOL_REF:
      fprintf (file, "%s", XSTR (addr, 0));
      if (addr_inc)
	fprintf (file, "+%d", addr_inc);
      break;
    case MEM:
      fprintf (file, "[memUFO:");
      output_address (XEXP (addr, 0));
      fprintf (file, "]");
      break;
    case CONST:
      output_address (XEXP (addr, 0));
      fprintf (file, " ;P_O_A const");
      break;
    case CODE_LABEL:
      fprintf (file, "L%d", XINT (addr, 3));
      break;
    default:
      fprintf (file, " p_o_a UFO, code=%d val=0x%x",
	       (int) GET_CODE (addr), INTVAL (addr));
      break;
    }
  addr_inc = 0;
}


/*
 *  Return non zero if the LS 16 bits of the given value has just one bit set,
 *  otherwise return zero. Note this function may be used to detect one
 *  bit clear by inverting the param.
 */
int
one_bit_set_p (x)
     int x;
{
  x &= 0xffff; 
  return x && (x & (x - 1)) == 0;
}


/*
 * Return the number of the least significant bit set, using the  same
 * convention for bit numbering as in the MIL-STD-1750 sb instruction.
 */
int
which_bit (x)
     int x;
{
  int b = 15;

  while (b > 0 && (x & 1) == 0)
    {
      b--;
      x >>= 1;
    }

  return b;
}