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*/

/* Generate a normal/denormal number with over,under handling
   sn is sign
   xe is an unbiased exponent
   xm is 3bit extended precision value.  */
ieee754sp
ieee754sp_format(int sn, int xe, uint32_t xm)
{
  xe += SP_EBIAS;

  if (UNLIKELY (xe < SP_EBIAS + SP_EMIN))
    {
      /* Strip lower bits.  */
      int es;
	
      if (IEEE754_NO_DENORMS ())
	{
	  SETCX(IEEE754_UNDERFLOW);
	  return ieee754sp_zero (sn);
	}
	
      /* Sticky right shift es bits.  */
      es = SP_EBIAS + SP_EMIN - xe;
      SPXSRSXn (es);
    }

  if (xm & (SP_MBIT(SP_GUARDBITS)-1))
    {
      SETCX(IEEE754_INEXACT);
      /* Inexact must round off guard bits.  */
      switch (IEEE754_GET_RM ())
	{
	case IEEE754_RZ:
	  break;
	case IEEE754_RN:
	  xm += ((0x1 << (SP_GUARDBITS - 1)) - 1)
		  + ((xm >> SP_GUARDBITS) & 1);
	  break;
	case IEEE754_RU:	/* toward +Infinity */
	  if (!sn)
	    xm += (0x1 << SP_GUARDBITS);
	  break;
	case IEEE754_RD:	/* toward -Infinity */
	  if (sn)
	    xm += (0x1 << SP_GUARDBITS);
	  break;
	}

    /* Adjust exponent for rounding overflow.  */
    if (xm >> (SP_MBITS + 1 + SP_GUARDBITS))
      {
	xm >>=1;
	xe++;
      }
    } 

  /* Strip grs bits.  */
  xm >>= SP_GUARDBITS;

  if (UNLIKELY (xe > SP_EBIAS + SP_EMAX))
    {
      SETCX(IEEE754_OVERFLOW);
      /* -O can be table indexed by (rm,sn).  */
      switch(IEEE754_GET_RM ())
	{
	case IEEE754_RN:
	  return ieee754sp_inf (sn);
	case IEEE754_RZ:
	  return ieee754sp_max (sn);
	case IEEE754_RU:	/* toward +Infinity */
	  if (sn == 0)
	    return ieee754sp_inf (0);
	  else
	    return ieee754sp_max (1);
	case IEEE754_RD:	/* toward -Infinity */
	  if (sn == 0)
	    return ieee754sp_max (0);
	  else
	    return ieee754sp_inf (1);
	}
    }

  /* Gen norm/denorm/zero.  */
  if (UNLIKELY ((xm & SP_HIDDEN_BIT) == 0))
    {
      /* We underflow (tiny/zero).  */
      SETCX(IEEE754_UNDERFLOW);
      xe = SP_EBIAS + SP_EMIN - 1;
    } 
  else 
    xm &= SP_MMASK;

  return buildsp (sn, xe, xm);
}
