i960.c

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	      if (! (RTX_OK_FOR_INDEX_P (XEXP (XEXP (op0, 0), 0), strict)
		     && SCALE_TERM_P (XEXP (XEXP (op0, 0), 1))))
		return 0;

	      if (RTX_OK_FOR_BASE_P (XEXP (op0, 1), strict)
		  && CONSTANT_P (op1))
		return 1;
	      else
		return 0;
	    }
	  else if (RTX_OK_FOR_BASE_P (XEXP (op0, 0), strict))
	    {
	      if (RTX_OK_FOR_INDEX_P (XEXP (op0, 1), strict)
		  && CONSTANT_P (op1))
		return 1;
	      else
		return 0;
	    }
	  else
	    return 0;
	}
      else if (GET_CODE (op0) == MULT)
	{
	  if (! (RTX_OK_FOR_INDEX_P (XEXP (op0, 0), strict)
		 && SCALE_TERM_P (XEXP (op0, 1))))
	    return 0;

	  if (RTX_OK_FOR_BASE_P (op1, strict))
	    return 1;
	  else if (CONSTANT_P (op1))
	    return 1;
	  else
	    return 0;
	}
      else
	return 0;
    }
  else if (GET_CODE (addr) == MULT)
    {
      if (! TARGET_COMPLEX_ADDR && ! reload_completed)
	return 0;

      return (RTX_OK_FOR_INDEX_P (XEXP (addr, 0), strict)
	      && SCALE_TERM_P (XEXP (addr, 1)));
    }
  else
    return 0;
}

/* Try machine-dependent ways of modifying an illegitimate address
   to be legitimate.  If we find one, return the new, valid address.
   This macro is used in only one place: `memory_address' in explow.c.

   This converts some non-canonical addresses to canonical form so they
   can be recognized.  */

rtx
legitimize_address (x, oldx, mode)
     register rtx x;
     register rtx oldx;
     enum machine_mode mode;
{ 
  if (GET_CODE (x) == SYMBOL_REF)
    {
      abort ();
      x = copy_to_reg (x);
    }

  if (! TARGET_COMPLEX_ADDR && ! reload_completed)
    return x;

  /* Canonicalize (plus (mult (reg) (const)) (plus (reg) (const)))
     into (plus (plus (mult (reg) (const)) (reg)) (const)).  This can be
     created by virtual register instantiation, register elimination, and
     similar optimizations.  */
  if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == MULT
      && GET_CODE (XEXP (x, 1)) == PLUS)
    x = gen_rtx (PLUS, Pmode,
		 gen_rtx (PLUS, Pmode, XEXP (x, 0), XEXP (XEXP (x, 1), 0)),
		 XEXP (XEXP (x, 1), 1));

  /* Canonicalize (plus (plus (mult (reg) (const)) (plus (reg) (const))) const)
     into (plus (plus (mult (reg) (const)) (reg)) (const)).  */
  else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == PLUS
	   && GET_CODE (XEXP (XEXP (x, 0), 0)) == MULT
	   && GET_CODE (XEXP (XEXP (x, 0), 1)) == PLUS
	   && CONSTANT_P (XEXP (x, 1)))
    {
      rtx constant, other;

      if (GET_CODE (XEXP (x, 1)) == CONST_INT)
	{
	  constant = XEXP (x, 1);
	  other = XEXP (XEXP (XEXP (x, 0), 1), 1);
	}
      else if (GET_CODE (XEXP (XEXP (XEXP (x, 0), 1), 1)) == CONST_INT)
	{
	  constant = XEXP (XEXP (XEXP (x, 0), 1), 1);
	  other = XEXP (x, 1);
	}
      else
	constant = 0;

      if (constant)
	x = gen_rtx (PLUS, Pmode,
		     gen_rtx (PLUS, Pmode, XEXP (XEXP (x, 0), 0),
			      XEXP (XEXP (XEXP (x, 0), 1), 0)),
		     plus_constant (other, INTVAL (constant)));
    }

  return x;
}

#if 0
/* Return the most stringent alignment that we are willing to consider
   objects of size SIZE and known alignment ALIGN as having. */
   
int
i960_alignment (size, align)
     int size;
     int align;
{
  int i;

  if (! TARGET_STRICT_ALIGN)
    if (TARGET_IC_COMPAT2_0 || align >= 4)
      {
	i = i960_object_bytes_bitalign (size) / BITS_PER_UNIT;
	if (i > align)
	  align = i;
      }

  return align;
}
#endif


int
hard_regno_mode_ok (regno, mode)
     int regno;
     enum machine_mode mode;
{
  if (regno < 32)
    {
      switch (mode)
	{
	case CCmode: case CC_UNSmode: case CC_CHKmode:
	  return 0;

	case DImode: case DFmode:
	  return (regno & 1) == 0;

	case TImode: case XFmode:
	  return (regno & 3) == 0;

	default:
	  return 1;
	}
    }
  else if (regno >= 32 && regno < 36)
    {
      switch (mode)
	{
	case SFmode: case DFmode: case XFmode:
	case SCmode: case DCmode:
	  return 1;

	default:
	  return 0;
	}
    }
  else if (regno == 36)
    {
      switch (mode)
	{
	case CCmode: case CC_UNSmode: case CC_CHKmode:
	  return 1;

	default:
	  return 0;
	}
    }
  else if (regno == 37)
    return 0;

  abort ();
}


/* Return the minimum alignment of an expression rtx X in bytes.  This takes
   advantage of machine specific facts, such as knowing that the frame pointer
   is always 16 byte aligned.  */

int
i960_expr_alignment (x, size)
     rtx x;
     int size;
{
  int align = 1;

  if (x == 0)
    return 1;

  switch (GET_CODE(x))
    {
    case CONST_INT:
      align = INTVAL(x);

      if ((align & 0xf) == 0)
	align = 16;
      else if ((align & 0x7) == 0)
	align = 8;
      else if ((align & 0x3) == 0)
	align = 4;
      else if ((align & 0x1) == 0)
	align = 2;
      else
	align = 1;
      break;

    case PLUS:
      align = MIN (i960_expr_alignment (XEXP (x, 0), size),
		   i960_expr_alignment (XEXP (x, 1), size));
      break;

    case SYMBOL_REF:
      /* If this is a valid program, objects are guaranteed to be
	 correctly aligned for whatever size the reference actually is. */
      align = i960_object_bytes_bitalign (size) / BITS_PER_UNIT;
      break;

    case REG:
      if (REGNO (x) == FRAME_POINTER_REGNUM)
	align = 16;
      break;

    case ASHIFT:
      align = i960_expr_alignment (XEXP (x, 0));

      if (GET_CODE (XEXP (x, 1)) == CONST_INT)
	{
	  align = align << INTVAL (XEXP (x, 1));
	  align = MIN (align, 16);
	}
      break;

    case MULT:
      align = (i960_expr_alignment (XEXP (x, 0), size) *
	       i960_expr_alignment (XEXP (x, 1), size));

      align = MIN (align, 16);
      break;
    }

  return align;
}

/* Return true if it is possible to reference both BASE and OFFSET, which
   have alignment at least as great as 4 byte, as if they had alignment valid
   for an object of size SIZE.  */

int
i960_improve_align (base, offset, size)
     rtx base;
     rtx offset;
     int size;
{
  int i, j;

  /* We have at least a word reference to the object, so we know it has to
     be aligned at least to 4 bytes.  */

  i = MIN (i960_expr_alignment (base, 4),
	   i960_expr_alignment (offset, 4));

  i = MAX (i, 4);

  /* We know the size of the request.  If strict align is not enabled, we
     can guess that the alignment is OK for the requested size.  */

  if (! TARGET_STRICT_ALIGN)
    if ((j = (i960_object_bytes_bitalign (size) / BITS_PER_UNIT)) > i)
      i = j;

  return (i >= size);
}

/* Return true if it is possible to access BASE and OFFSET, which have 4 byte
   (SImode) alignment as if they had 16 byte (TImode) alignment.  */

int
i960_si_ti (base, offset)
     rtx base;
     rtx offset;
{
  return i960_improve_align (base, offset, 16);
}

/* Return true if it is possible to access BASE and OFFSET, which have 4 byte
   (SImode) alignment as if they had 8 byte (DImode) alignment.  */

int
i960_si_di (base, offset)
     rtx base;
     rtx offset;
{
  return i960_improve_align (base, offset, 8);
}

/* Return raw values of size and alignment (in words) for the data
   type being accessed.  These values will be rounded by the caller.  */

static void 
i960_arg_size_and_align (mode, type, size_out, align_out)
     enum machine_mode mode;
     tree type;
     int *size_out;
     int *align_out;
{
  int size, align;

  /* Use formal alignment requirements of type being passed, except make
     it at least a word.  If we don't have a type, this is a library call,
     and the parm has to be of scalar type.  In this case, consider its
     formal alignment requirement to be its size in words.  */

  if (mode == BLKmode)
    size = (int_size_in_bytes (type) + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
  else if (mode == VOIDmode)
    {
      /* End of parm list.  */
      if (type == 0 || TYPE_MODE (type) != VOIDmode)
	abort ();
      size = 1;
    }
  else
    size = (GET_MODE_SIZE (mode) + UNITS_PER_WORD - 1) / UNITS_PER_WORD;

  if (type == 0)
    {
      /* ??? This is a hack to properly correct the alignment of XFmode
	 values without affecting anything else.  */
      if (size == 3)
	align = 4;
      else
	align = size;
    }
  else if (TYPE_ALIGN (type) >= BITS_PER_WORD)
    align = TYPE_ALIGN (type) / BITS_PER_WORD;
  else
    align = 1;

  *size_out  = size;
  *align_out = align;
}

/* On the 80960 the first 12 args are in registers and the rest are pushed.
   Any arg that is bigger than 4 words is placed on the stack and all
   subsequent arguments are placed on the stack.

   Additionally, parameters with an alignment requirement stronger than
   a word must be aligned appropriately.  Note that this means that a
   64 bit object with a 32 bit alignment is not 64 bit aligned and may be
   passed in an odd/even register pair.  */

/* Update CUM to advance past an argument described by MODE and TYPE.  */

void
i960_function_arg_advance (cum, mode, type, named)
     CUMULATIVE_ARGS *cum;
     enum machine_mode mode;
     tree type;
     int named;
{
  int size, align;

  i960_arg_size_and_align (mode, type, &size, &align);

  if (size > 4 || cum->ca_nstackparms != 0
      || (size + ROUND_PARM (cum->ca_nregparms, align)) > NPARM_REGS
      || MUST_PASS_IN_STACK (mode, type))
    {
      /* Indicate that all the registers are in use, even if all are not,
	 so va_start will compute the right value.  */
      cum->ca_nregparms = NPARM_REGS;
      cum->ca_nstackparms = ROUND_PARM (cum->ca_nstackparms, align) + size;
    }
  else
    cum->ca_nregparms = ROUND_PARM (cum->ca_nregparms, align) + size;
}

/* Return the register that the argument described by MODE and TYPE is
   passed in, or else return 0 if it is passed on the stack.  */

rtx
i960_function_arg (cum, mode, type, named)
     CUMULATIVE_ARGS *cum;
     enum machine_mode mode;
     tree type;
     int named;
{
  rtx ret;
  int size, align;

  i960_arg_size_and_align (mode, type, &size, &align);

  if (size > 4 || cum->ca_nstackparms != 0
      || (size + ROUND_PARM (cum->ca_nregparms, align)) > NPARM_REGS
      || MUST_PASS_IN_STACK (mode, type))
    {
      cum->ca_nstackparms = ROUND_PARM (cum->ca_nstackparms, align);
      ret = 0;
    }
  else
    {
      cum->ca_nregparms = ROUND_PARM (cum->ca_nregparms, align);
      ret = gen_rtx (REG, mode, cum->ca_nregparms);
    }

  return ret;
}

/* Floating-point support.  */

void
i960_output_long_double (file, value)
     FILE *file;
     REAL_VALUE_TYPE value;
{
  long value_long[3];
  char dstr[30];

  REAL_VALUE_TO_TARGET_LONG_DOUBLE (value, value_long);
  REAL_VALUE_TO_DECIMAL (value, "%.20g", dstr);

  fprintf (file,
	   "\t.word\t0x%08lx\t\t# %s\n\t.word\t0x%08lx\n\t.word\t0x%08lx\n",
	   value_long[0], dstr, value_long[1], value_long[2]);
  fprintf (file, "\t.word\t0x0\n");
}

void
i960_output_double (file, value)
     FILE *file;
     REAL_VALUE_TYPE value;
{
  long value_long[2];
  char dstr[30];

  REAL_VALUE_TO_TARGET_DOUBLE (value, value_long);
  REAL_VALUE_TO_DECIMAL (value, "%.20g", dstr);

  fprintf (file, "\t.word\t0x%08lx\t\t# %s\n\t.word\t0x%08lx\n",
	   value_long[0], dstr, value_long[1]);
}
  
void
i960_output_float (file, value)
     FILE *file;
     REAL_VALUE_TYPE value;
{
  long value_long;
  char dstr[30];

  REAL_VALUE_TO_TARGET_SINGLE (value, value_long);
  REAL_VALUE_TO_DECIMAL (value, "%.12g", dstr);

  fprintf (file, "\t.word\t0x%08lx\t\t# %s (float)\n", value_long, dstr);
}

/* Return the number of bits that an object of size N bytes is aligned to.  */

int
i960_object_bytes_bitalign (n)
     int n;
{
  if (n > 8)      n = 128;
  else if (n > 4) n = 64;
  else if (n > 2) n = 32;
  else if (n > 1) n = 16;
  else            n = 8;

  return n;
}

/* Compute the alignment for an aggregate type TSIZE.
   Alignment is MAX (greatest member alignment,
                     MIN (pragma align, structure size alignment)).  */

int
i960_round_align (align, tsize)
     int align;
     tree tsize;
{
  int new_align;

  if (TREE_CODE (tsize) != INTEGER_CST)
    return align;

  new_align = i960_object_bytes_bitalign (TREE_INT_CST_LOW (tsize)
					  / BITS_PER_UNIT);
  /* Handle #pragma align.  */
  if (new_align > i960_maxbitalignment)
    new_align = i960_maxbitalignment;

  if (align < new_align)
    align = new_align;

  return align;
}

/* Do any needed setup for a varargs function.  For the i960, we must
   create a register parameter block if one doesn't exist, and then copy
   all register parameters to memory.  */

void
i960_s