int
dbl_fdiv (dbl_floating_point * srcptr1, dbl_floating_point * srcptr2,
	  dbl_floating_point * dstptr, unsigned int *status)
{
	register unsigned int opnd1p1, opnd1p2, opnd2p1, opnd2p2;
	register unsigned int opnd3p1, opnd3p2, resultp1, resultp2;
	register int dest_exponent, count;
	register boolean inexact = FALSE, guardbit = FALSE, stickybit = FALSE;
	boolean is_tiny;

	Dbl_copyfromptr(srcptr1,opnd1p1,opnd1p2);
	Dbl_copyfromptr(srcptr2,opnd2p1,opnd2p2);
	/*
	 * set sign bit of result
	 */
	if (Dbl_sign(opnd1p1) ^ Dbl_sign(opnd2p1))
		Dbl_setnegativezerop1(resultp1);
	else Dbl_setzerop1(resultp1);
	/*
	 * check first operand for NaN's or infinity
	 */
	if (Dbl_isinfinity_exponent(opnd1p1)) {
		if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
			if (Dbl_isnotnan(opnd2p1,opnd2p2)) {
				if (Dbl_isinfinity(opnd2p1,opnd2p2)) {
					/*
					 * invalid since both operands
					 * are infinity
					 */
					if (Is_invalidtrap_enabled())
						return(INVALIDEXCEPTION);
					Set_invalidflag();
					Dbl_makequietnan(resultp1,resultp2);
					Dbl_copytoptr(resultp1,resultp2,dstptr);
					return(NOEXCEPTION);
				}
				/*
				 * return infinity
				 */
				Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
				Dbl_copytoptr(resultp1,resultp2,dstptr);
				return(NOEXCEPTION);
			}
		}
		else {
			/*
			 * is NaN; signaling or quiet?
			 */
			if (Dbl_isone_signaling(opnd1p1)) {
				/* trap if INVALIDTRAP enabled */
				if (Is_invalidtrap_enabled())
					return(INVALIDEXCEPTION);
				/* make NaN quiet */
				Set_invalidflag();
				Dbl_set_quiet(opnd1p1);
			}
			/*
			 * is second operand a signaling NaN?
			 */
			else if (Dbl_is_signalingnan(opnd2p1)) {
				/* trap if INVALIDTRAP enabled */
				if (Is_invalidtrap_enabled())
					return(INVALIDEXCEPTION);
				/* make NaN quiet */
				Set_invalidflag();
				Dbl_set_quiet(opnd2p1);
				Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
				return(NOEXCEPTION);
			}
			/*
			 * return quiet NaN
			 */
			Dbl_copytoptr(opnd1p1,opnd1p2,dstptr);
			return(NOEXCEPTION);
		}
	}
	/*
	 * check second operand for NaN's or infinity
	 */
	if (Dbl_isinfinity_exponent(opnd2p1)) {
		if (Dbl_iszero_mantissa(opnd2p1,opnd2p2)) {
			/*
			 * return zero
			 */
			Dbl_setzero_exponentmantissa(resultp1,resultp2);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			return(NOEXCEPTION);
		}
                /*
                 * is NaN; signaling or quiet?
                 */
                if (Dbl_isone_signaling(opnd2p1)) {
                        /* trap if INVALIDTRAP enabled */
                        if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
                        /* make NaN quiet */
                        Set_invalidflag();
                        Dbl_set_quiet(opnd2p1);
                }
                /*
                 * return quiet NaN
                 */
		Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
                return(NOEXCEPTION);
	}
        /*
         * check for division by zero
         */
        if (Dbl_iszero_exponentmantissa(opnd2p1,opnd2p2)) {
                if (Dbl_iszero_exponentmantissa(opnd1p1,opnd1p2)) {
                        /* invalid since both operands are zero */
                        if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
                        Set_invalidflag();
                        Dbl_makequietnan(resultp1,resultp2);
                        Dbl_copytoptr(resultp1,resultp2,dstptr);
                        return(NOEXCEPTION);
                }
                if (Is_divisionbyzerotrap_enabled())
			return(DIVISIONBYZEROEXCEPTION);
                Set_divisionbyzeroflag();
                Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
                Dbl_copytoptr(resultp1,resultp2,dstptr);
                return(NOEXCEPTION);
        }
	/*
	 * Generate exponent
	 */
	dest_exponent = Dbl_exponent(opnd1p1) - Dbl_exponent(opnd2p1) + DBL_BIAS;

	/*
	 * Generate mantissa
	 */
	if (Dbl_isnotzero_exponent(opnd1p1)) {
		/* set hidden bit */
		Dbl_clear_signexponent_set_hidden(opnd1p1);
	}
	else {
		/* check for zero */
		if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
			Dbl_setzero_exponentmantissa(resultp1,resultp2);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			return(NOEXCEPTION);
		}
                /* is denormalized, want to normalize */
                Dbl_clear_signexponent(opnd1p1);
                Dbl_leftshiftby1(opnd1p1,opnd1p2);
		Dbl_normalize(opnd1p1,opnd1p2,dest_exponent);
	}
	/* opnd2 needs to have hidden bit set with msb in hidden bit */
	if (Dbl_isnotzero_exponent(opnd2p1)) {
		Dbl_clear_signexponent_set_hidden(opnd2p1);
	}
	else {
                /* is denormalized; want to normalize */
                Dbl_clear_signexponent(opnd2p1);
                Dbl_leftshiftby1(opnd2p1,opnd2p2);
                while (Dbl_iszero_hiddenhigh7mantissa(opnd2p1)) {
                        dest_exponent+=8;
                        Dbl_leftshiftby8(opnd2p1,opnd2p2);
                }
                if (Dbl_iszero_hiddenhigh3mantissa(opnd2p1)) {
                        dest_exponent+=4;
                        Dbl_leftshiftby4(opnd2p1,opnd2p2);
                }
                while (Dbl_iszero_hidden(opnd2p1)) {
                        dest_exponent++;
                        Dbl_leftshiftby1(opnd2p1,opnd2p2);
                }
	}

	/* Divide the source mantissas */

	/*
	 * A non-restoring divide algorithm is used.
	 */
	Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2);
	Dbl_setzero(opnd3p1,opnd3p2);
	for (count=1; count <= DBL_P && (opnd1p1 || opnd1p2); count++) {
		Dbl_leftshiftby1(opnd1p1,opnd1p2);
		Dbl_leftshiftby1(opnd3p1,opnd3p2);
		if (Dbl_iszero_sign(opnd1p1)) {
			Dbl_setone_lowmantissap2(opnd3p2);
			Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2);
		}
		else {
			Twoword_add(opnd1p1, opnd1p2, opnd2p1, opnd2p2);
		}
	}
	if (count <= DBL_P) {
		Dbl_leftshiftby1(opnd3p1,opnd3p2);
		Dbl_setone_lowmantissap2(opnd3p2);
		Dbl_leftshift(opnd3p1,opnd3p2,(DBL_P-count));
		if (Dbl_iszero_hidden(opnd3p1)) {
			Dbl_leftshiftby1(opnd3p1,opnd3p2);
			dest_exponent--;
		}
	}
	else {
		if (Dbl_iszero_hidden(opnd3p1)) {
			/* need to get one more bit of result */
			Dbl_leftshiftby1(opnd1p1,opnd1p2);
			Dbl_leftshiftby1(opnd3p1,opnd3p2);
			if (Dbl_iszero_sign(opnd1p1)) {
				Dbl_setone_lowmantissap2(opnd3p2);
				Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2);
			}
			else {
				Twoword_add(opnd1p1,opnd1p2,opnd2p1,opnd2p2);
			}
			dest_exponent--;
		}
		if (Dbl_iszero_sign(opnd1p1)) guardbit = TRUE;
		stickybit = Dbl_allp1(opnd1p1) || Dbl_allp2(opnd1p2);
	}
	inexact = guardbit | stickybit;

	/*
	 * round result
	 */
	if (inexact && (dest_exponent > 0 || Is_underflowtrap_enabled())) {
		Dbl_clear_signexponent(opnd3p1);
		switch (Rounding_mode()) {
			case ROUNDPLUS:
				if (Dbl_iszero_sign(resultp1))
					Dbl_increment(opnd3p1,opnd3p2);
				break;
			case ROUNDMINUS:
				if (Dbl_isone_sign(resultp1))
					Dbl_increment(opnd3p1,opnd3p2);
				break;
			case ROUNDNEAREST:
				if (guardbit && (stickybit ||
				    Dbl_isone_lowmantissap2(opnd3p2))) {
					Dbl_increment(opnd3p1,opnd3p2);
				}
		}
		if (Dbl_isone_hidden(opnd3p1)) dest_exponent++;
	}
	Dbl_set_mantissa(resultp1,resultp2,opnd3p1,opnd3p2);

        /*
         * Test for overflow
         */
	if (dest_exponent >= DBL_INFINITY_EXPONENT) {
                /* trap if OVERFLOWTRAP enabled */
                if (Is_overflowtrap_enabled()) {
                        /*
                         * Adjust bias of result
                         */
                        Dbl_setwrapped_exponent(resultp1,dest_exponent,ovfl);
                        Dbl_copytoptr(resultp1,resultp2,dstptr);
                        if (inexact)
                            if (Is_inexacttrap_enabled())
                                return(OVERFLOWEXCEPTION | INEXACTEXCEPTION);
                            else Set_inexactflag();
                        return(OVERFLOWEXCEPTION);
                }
		Set_overflowflag();
                /* set result to infinity or largest number */
		Dbl_setoverflow(resultp1,resultp2);
		inexact = TRUE;
	}
        /*
         * Test for underflow
         */
	else if (dest_exponent <= 0) {
                /* trap if UNDERFLOWTRAP enabled */
                if (Is_underflowtrap_enabled()) {
                        /*
                         * Adjust bias of result
                         */
                        Dbl_setwrapped_exponent(resultp1,dest_exponent,unfl);
                        Dbl_copytoptr(resultp1,resultp2,dstptr);
                        if (inexact)
                            if (Is_inexacttrap_enabled())
                                return(UNDERFLOWEXCEPTION | INEXACTEXCEPTION);
                            else Set_inexactflag();
                        return(UNDERFLOWEXCEPTION);
                }

		/* Determine if should set underflow flag */
		is_tiny = TRUE;
		if (dest_exponent == 0 && inexact) {
			switch (Rounding_mode()) {
			case ROUNDPLUS:
				if (Dbl_iszero_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
					    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDMINUS:
				if (Dbl_isone_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
					    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDNEAREST:
				if (guardbit && (stickybit ||
				    Dbl_isone_lowmantissap2(opnd3p2))) {
					Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
					    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			}
		}

                /*
                 * denormalize result or set to signed zero
                 */
		stickybit = inexact;
		Dbl_denormalize(opnd3p1,opnd3p2,dest_exponent,guardbit,
		 stickybit,inexact);

		/* return rounded number */
		if (inexact) {
			switch (Rounding_mode()) {
			case ROUNDPLUS:
				if (Dbl_iszero_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDMINUS:
				if (Dbl_isone_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDNEAREST:
				if (guardbit && (stickybit ||
				    Dbl_isone_lowmantissap2(opnd3p2))) {
					Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			}
			if (is_tiny) Set_underflowflag();
                }
		Dbl_set_exponentmantissa(resultp1,resultp2,opnd3p1,opnd3p2);
	}
	else Dbl_set_exponent(resultp1,dest_exponent);
	Dbl_copytoptr(resultp1,resultp2,dstptr);

	/* check for inexact */
	if (inexact) {
		if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
		else Set_inexactflag();
	}
	return(NOEXCEPTION);
}
int
dbl_fdiv (dbl_floating_point * srcptr1, dbl_floating_point * srcptr2,
	  dbl_floating_point * dstptr, unsigned int *status)
{
	register unsigned int opnd1p1, opnd1p2, opnd2p1, opnd2p2;
	register unsigned int opnd3p1, opnd3p2, resultp1, resultp2;
	register int dest_exponent, count;
	register boolean inexact = FALSE, guardbit = FALSE, stickybit = FALSE;
	boolean is_tiny;

	Dbl_copyfromptr(srcptr1,opnd1p1,opnd1p2);
	Dbl_copyfromptr(srcptr2,opnd2p1,opnd2p2);
	/* 
                           
  */
	if (Dbl_sign(opnd1p1) ^ Dbl_sign(opnd2p1)) 
		Dbl_setnegativezerop1(resultp1);  
	else Dbl_setzerop1(resultp1);
	/*
                                             
  */
	if (Dbl_isinfinity_exponent(opnd1p1)) {
		if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
			if (Dbl_isnotnan(opnd2p1,opnd2p2)) {
				if (Dbl_isinfinity(opnd2p1,opnd2p2)) {
					/* 
                                    
                     
      */
					if (Is_invalidtrap_enabled())
                                		return(INVALIDEXCEPTION);
                                	Set_invalidflag();
                                	Dbl_makequietnan(resultp1,resultp2);
					Dbl_copytoptr(resultp1,resultp2,dstptr);
					return(NOEXCEPTION);
				}
				/*
                       
      */
				Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
				Dbl_copytoptr(resultp1,resultp2,dstptr);
				return(NOEXCEPTION);
			}
		}
		else {
                	/*
                                                
                   */
                	if (Dbl_isone_signaling(opnd1p1)) {
                        	/*                             */
                        	if (Is_invalidtrap_enabled())
                            		return(INVALIDEXCEPTION);
                        	/*                */
                        	Set_invalidflag();
                        	Dbl_set_quiet(opnd1p1);
                	}
			/* 
                                         
    */
			else if (Dbl_is_signalingnan(opnd2p1)) {
                        	/*                             */
                        	if (Is_invalidtrap_enabled())
                            		return(INVALIDEXCEPTION);
                        	/*                */
                        	Set_invalidflag();
                        	Dbl_set_quiet(opnd2p1);
				Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
                		return(NOEXCEPTION);
			}
                	/*
                                     
                   */
			Dbl_copytoptr(opnd1p1,opnd1p2,dstptr);
                	return(NOEXCEPTION);
		}
	}
	/*
                                              
  */
	if (Dbl_isinfinity_exponent(opnd2p1)) {
		if (Dbl_iszero_mantissa(opnd2p1,opnd2p2)) {
			/*
                 
    */
			Dbl_setzero_exponentmantissa(resultp1,resultp2);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			return(NOEXCEPTION);
		}
                /*
                                              
                 */
                if (Dbl_isone_signaling(opnd2p1)) {
                        /*                             */
                        if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
                        /*                */
                        Set_invalidflag();
                        Dbl_set_quiet(opnd2p1);
                }
                /*
                                   
                 */
		Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
                return(NOEXCEPTION);
	}
        /*
                                     
         */
        if (Dbl_iszero_exponentmantissa(opnd2p1,opnd2p2)) {
                if (Dbl_iszero_exponentmantissa(opnd1p1,opnd1p2)) {
                        /*                                      */
                        if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
                        Set_invalidflag();
                        Dbl_makequietnan(resultp1,resultp2);
                        Dbl_copytoptr(resultp1,resultp2,dstptr);
                        return(NOEXCEPTION);
                }
                if (Is_divisionbyzerotrap_enabled())
                       	return(DIVISIONBYZEROEXCEPTION);
                Set_divisionbyzeroflag();
                Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
                Dbl_copytoptr(resultp1,resultp2,dstptr);
                return(NOEXCEPTION);
        }
	/*
                      
  */
	dest_exponent = Dbl_exponent(opnd1p1) - Dbl_exponent(opnd2p1) + DBL_BIAS;

	/*
                     
  */
	if (Dbl_isnotzero_exponent(opnd1p1)) {
		/*                */
		Dbl_clear_signexponent_set_hidden(opnd1p1);
	}
	else {
		/*                */
		if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
			Dbl_setzero_exponentmantissa(resultp1,resultp2);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			return(NOEXCEPTION);
		}
                /*                                    */
                Dbl_clear_signexponent(opnd1p1);
                Dbl_leftshiftby1(opnd1p1,opnd1p2);
		Dbl_normalize(opnd1p1,opnd1p2,dest_exponent);
	}
	/*                                                           */
	if (Dbl_isnotzero_exponent(opnd2p1)) {
		Dbl_clear_signexponent_set_hidden(opnd2p1);
	}
	else {
                /*                                    */
                Dbl_clear_signexponent(opnd2p1);
                Dbl_leftshiftby1(opnd2p1,opnd2p2);
                while (Dbl_iszero_hiddenhigh7mantissa(opnd2p1)) {
                        dest_exponent+=8;
                        Dbl_leftshiftby8(opnd2p1,opnd2p2);
                }
                if (Dbl_iszero_hiddenhigh3mantissa(opnd2p1)) {
                        dest_exponent+=4;
                        Dbl_leftshiftby4(opnd2p1,opnd2p2);
                }
                while (Dbl_iszero_hidden(opnd2p1)) {
                        dest_exponent++;
                        Dbl_leftshiftby1(opnd2p1,opnd2p2);
                }
	}

	/*                             */

	/* 
                                             
  */
	Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2);
	Dbl_setzero(opnd3p1,opnd3p2);
	for (count=1; count <= DBL_P && (opnd1p1 || opnd1p2); count++) {
		Dbl_leftshiftby1(opnd1p1,opnd1p2);
		Dbl_leftshiftby1(opnd3p1,opnd3p2);
		if (Dbl_iszero_sign(opnd1p1)) {
			Dbl_setone_lowmantissap2(opnd3p2);
			Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2);
		}
		else {
			Twoword_add(opnd1p1, opnd1p2, opnd2p1, opnd2p2);
		}
	}
	if (count <= DBL_P) {
		Dbl_leftshiftby1(opnd3p1,opnd3p2);
		Dbl_setone_lowmantissap2(opnd3p2);
		Dbl_leftshift(opnd3p1,opnd3p2,(DBL_P-count));
		if (Dbl_iszero_hidden(opnd3p1)) {
			Dbl_leftshiftby1(opnd3p1,opnd3p2);
			dest_exponent--;
		}
	}
	else {
		if (Dbl_iszero_hidden(opnd3p1)) {
			/*                                    */
			Dbl_leftshiftby1(opnd1p1,opnd1p2);
			Dbl_leftshiftby1(opnd3p1,opnd3p2);
			if (Dbl_iszero_sign(opnd1p1)) {
				Dbl_setone_lowmantissap2(opnd3p2);
				Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2);
			}
			else {
				Twoword_add(opnd1p1,opnd1p2,opnd2p1,opnd2p2);
			}
			dest_exponent--;
		}
		if (Dbl_iszero_sign(opnd1p1)) guardbit = TRUE;
		stickybit = Dbl_allp1(opnd1p1) || Dbl_allp2(opnd1p2);
	}
	inexact = guardbit | stickybit;

	/* 
                 
  */
	if (inexact && (dest_exponent > 0 || Is_underflowtrap_enabled())) {
		Dbl_clear_signexponent(opnd3p1);
		switch (Rounding_mode()) {
			case ROUNDPLUS: 
				if (Dbl_iszero_sign(resultp1)) 
					Dbl_increment(opnd3p1,opnd3p2);
				break;
			case ROUNDMINUS: 
				if (Dbl_isone_sign(resultp1)) 
					Dbl_increment(opnd3p1,opnd3p2);
				break;
			case ROUNDNEAREST:
				if (guardbit && (stickybit || 
				    Dbl_isone_lowmantissap2(opnd3p2))) {
			      		Dbl_increment(opnd3p1,opnd3p2);
				}
		}
		if (Dbl_isone_hidden(opnd3p1)) dest_exponent++;
	}
	Dbl_set_mantissa(resultp1,resultp2,opnd3p1,opnd3p2);

        /* 
                            
         */
	if (dest_exponent >= DBL_INFINITY_EXPONENT) {
                /*                              */
                if (Is_overflowtrap_enabled()) {
                        /*
                                                
                         */
                        Dbl_setwrapped_exponent(resultp1,dest_exponent,ovfl);
                        Dbl_copytoptr(resultp1,resultp2,dstptr);
                        if (inexact) 
                            if (Is_inexacttrap_enabled())
                                return(OVERFLOWEXCEPTION | INEXACTEXCEPTION);
                            else Set_inexactflag();
                        return(OVERFLOWEXCEPTION);
                }
		Set_overflowflag();
                /*                                          */
		Dbl_setoverflow(resultp1,resultp2);
		inexact = TRUE;
	}
        /* 
                             
         */
	else if (dest_exponent <= 0) {
                /*                               */
                if (Is_underflowtrap_enabled()) {
                        /*
                                                
                         */
                        Dbl_setwrapped_exponent(resultp1,dest_exponent,unfl);
                        Dbl_copytoptr(resultp1,resultp2,dstptr);
                        if (inexact) 
                            if (Is_inexacttrap_enabled())
                                return(UNDERFLOWEXCEPTION | INEXACTEXCEPTION);
                            else Set_inexactflag();
                        return(UNDERFLOWEXCEPTION);
                }

		/*                                        */
		is_tiny = TRUE;
		if (dest_exponent == 0 && inexact) {
			switch (Rounding_mode()) {
			case ROUNDPLUS: 
				if (Dbl_iszero_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
                			    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDMINUS: 
				if (Dbl_isone_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
                			    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDNEAREST:
				if (guardbit && (stickybit || 
				    Dbl_isone_lowmantissap2(opnd3p2))) {
				      	Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
                			    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			}
		}

                /*
                                                           
                 */
		stickybit = inexact;
		Dbl_denormalize(opnd3p1,opnd3p2,dest_exponent,guardbit,
		 stickybit,inexact);

		/*                       */ 
		if (inexact) {
			switch (Rounding_mode()) {
			case ROUNDPLUS:
				if (Dbl_iszero_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDMINUS: 
				if (Dbl_isone_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDNEAREST:
				if (guardbit && (stickybit || 
				    Dbl_isone_lowmantissap2(opnd3p2))) {
			      		Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			}
                	if (is_tiny) Set_underflowflag();
                }
		Dbl_set_exponentmantissa(resultp1,resultp2,opnd3p1,opnd3p2);
	}
	else Dbl_set_exponent(resultp1,dest_exponent);
	Dbl_copytoptr(resultp1,resultp2,dstptr);

	/*                   */
	if (inexact) {
		if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
		else Set_inexactflag();
	}
	return(NOEXCEPTION);
}
Exemple #3
0
int
dbl_fmpy(
	    dbl_floating_point *srcptr1,
	    dbl_floating_point *srcptr2,
	    dbl_floating_point *dstptr,
	    unsigned int *status)
{
	register unsigned int opnd1p1, opnd1p2, opnd2p1, opnd2p2;
	register unsigned int opnd3p1, opnd3p2, resultp1, resultp2;
	register int dest_exponent, count;
	register boolean inexact = FALSE, guardbit = FALSE, stickybit = FALSE;
	boolean is_tiny;

	Dbl_copyfromptr(srcptr1,opnd1p1,opnd1p2);
	Dbl_copyfromptr(srcptr2,opnd2p1,opnd2p2);

	/*
	 * set sign bit of result
	 */
	if (Dbl_sign(opnd1p1) ^ Dbl_sign(opnd2p1))
		Dbl_setnegativezerop1(resultp1);
	else Dbl_setzerop1(resultp1);
	/*
	 * check first operand for NaN's or infinity
	 */
	if (Dbl_isinfinity_exponent(opnd1p1)) {
		if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
			if (Dbl_isnotnan(opnd2p1,opnd2p2)) {
				if (Dbl_iszero_exponentmantissa(opnd2p1,opnd2p2)) {
					/*
					 * invalid since operands are infinity
					 * and zero
					 */
					if (Is_invalidtrap_enabled())
                                		return(INVALIDEXCEPTION);
                                	Set_invalidflag();
                                	Dbl_makequietnan(resultp1,resultp2);
					Dbl_copytoptr(resultp1,resultp2,dstptr);
					return(NOEXCEPTION);
				}
				/*
			 	 * return infinity
			 	 */
				Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
				Dbl_copytoptr(resultp1,resultp2,dstptr);
				return(NOEXCEPTION);
			}
		}
		else {
                	/*
                 	 * is NaN; signaling or quiet?
                 	 */
                	if (Dbl_isone_signaling(opnd1p1)) {
                        	/* trap if INVALIDTRAP enabled */
                        	if (Is_invalidtrap_enabled())
                            		return(INVALIDEXCEPTION);
                        	/* make NaN quiet */
                        	Set_invalidflag();
                        	Dbl_set_quiet(opnd1p1);
                	}
			/*
			 * is second operand a signaling NaN?
			 */
			else if (Dbl_is_signalingnan(opnd2p1)) {
                        	/* trap if INVALIDTRAP enabled */
                        	if (Is_invalidtrap_enabled())
                            		return(INVALIDEXCEPTION);
                        	/* make NaN quiet */
                        	Set_invalidflag();
                        	Dbl_set_quiet(opnd2p1);
				Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
                		return(NOEXCEPTION);
			}
                	/*
                 	 * return quiet NaN
                 	 */
			Dbl_copytoptr(opnd1p1,opnd1p2,dstptr);
                	return(NOEXCEPTION);
		}
	}
	/*
	 * check second operand for NaN's or infinity
	 */
	if (Dbl_isinfinity_exponent(opnd2p1)) {
		if (Dbl_iszero_mantissa(opnd2p1,opnd2p2)) {
			if (Dbl_iszero_exponentmantissa(opnd1p1,opnd1p2)) {
				/* invalid since operands are zero & infinity */
				if (Is_invalidtrap_enabled())
                                	return(INVALIDEXCEPTION);
                                Set_invalidflag();
                                Dbl_makequietnan(opnd2p1,opnd2p2);
				Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
				return(NOEXCEPTION);
			}
			/*
			 * return infinity
			 */
			Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			return(NOEXCEPTION);
		}
                /*
                 * is NaN; signaling or quiet?
                 */
                if (Dbl_isone_signaling(opnd2p1)) {
                        /* trap if INVALIDTRAP enabled */
                        if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
                        /* make NaN quiet */
                        Set_invalidflag();
                        Dbl_set_quiet(opnd2p1);
                }
                /*
                 * return quiet NaN
                 */
		Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
                return(NOEXCEPTION);
	}
	/*
	 * Generate exponent
	 */
	dest_exponent = Dbl_exponent(opnd1p1) + Dbl_exponent(opnd2p1) -DBL_BIAS;

	/*
	 * Generate mantissa
	 */
	if (Dbl_isnotzero_exponent(opnd1p1)) {
		/* set hidden bit */
		Dbl_clear_signexponent_set_hidden(opnd1p1);
	}
	else {
		/* check for zero */
		if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
			Dbl_setzero_exponentmantissa(resultp1,resultp2);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			return(NOEXCEPTION);
		}
                /* is denormalized, adjust exponent */
                Dbl_clear_signexponent(opnd1p1);
                Dbl_leftshiftby1(opnd1p1,opnd1p2);
		Dbl_normalize(opnd1p1,opnd1p2,dest_exponent);
	}
	/* opnd2 needs to have hidden bit set with msb in hidden bit */
	if (Dbl_isnotzero_exponent(opnd2p1)) {
		Dbl_clear_signexponent_set_hidden(opnd2p1);
	}
	else {
		/* check for zero */
		if (Dbl_iszero_mantissa(opnd2p1,opnd2p2)) {
			Dbl_setzero_exponentmantissa(resultp1,resultp2);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			return(NOEXCEPTION);
		}
                /* is denormalized; want to normalize */
                Dbl_clear_signexponent(opnd2p1);
                Dbl_leftshiftby1(opnd2p1,opnd2p2);
		Dbl_normalize(opnd2p1,opnd2p2,dest_exponent);
	}

	/* Multiply two source mantissas together */

	/* make room for guard bits */
	Dbl_leftshiftby7(opnd2p1,opnd2p2);
	Dbl_setzero(opnd3p1,opnd3p2);
        /*
         * Four bits at a time are inspected in each loop, and a
         * simple shift and add multiply algorithm is used.
         */
	for (count=1;count<=DBL_P;count+=4) {
		stickybit |= Dlow4p2(opnd3p2);
		Dbl_rightshiftby4(opnd3p1,opnd3p2);
		if (Dbit28p2(opnd1p2)) {
	 		/* Twoword_add should be an ADDC followed by an ADD. */
                        Twoword_add(opnd3p1, opnd3p2, opnd2p1<<3 | opnd2p2>>29,
				    opnd2p2<<3);
		}
		if (Dbit29p2(opnd1p2)) {
                        Twoword_add(opnd3p1, opnd3p2, opnd2p1<<2 | opnd2p2>>30,
				    opnd2p2<<2);
		}
		if (Dbit30p2(opnd1p2)) {
                        Twoword_add(opnd3p1, opnd3p2, opnd2p1<<1 | opnd2p2>>31,
				    opnd2p2<<1);
		}
		if (Dbit31p2(opnd1p2)) {
                        Twoword_add(opnd3p1, opnd3p2, opnd2p1, opnd2p2);
		}
		Dbl_rightshiftby4(opnd1p1,opnd1p2);
	}
	if (Dbit3p1(opnd3p1)==0) {
		Dbl_leftshiftby1(opnd3p1,opnd3p2);
	}
	else {
		/* result mantissa >= 2. */
		dest_exponent++;
	}
	/* check for denormalized result */
	while (Dbit3p1(opnd3p1)==0) {
		Dbl_leftshiftby1(opnd3p1,opnd3p2);
		dest_exponent--;
	}
	/*
	 * check for guard, sticky and inexact bits
	 */
	stickybit |= Dallp2(opnd3p2) << 25;
	guardbit = (Dallp2(opnd3p2) << 24) >> 31;
	inexact = guardbit | stickybit;

	/* align result mantissa */
	Dbl_rightshiftby8(opnd3p1,opnd3p2);

	/*
	 * round result
	 */
	if (inexact && (dest_exponent>0 || Is_underflowtrap_enabled())) {
		Dbl_clear_signexponent(opnd3p1);
		switch (Rounding_mode()) {
			case ROUNDPLUS:
				if (Dbl_iszero_sign(resultp1))
					Dbl_increment(opnd3p1,opnd3p2);
				break;
			case ROUNDMINUS:
				if (Dbl_isone_sign(resultp1))
					Dbl_increment(opnd3p1,opnd3p2);
				break;
			case ROUNDNEAREST:
				if (guardbit) {
			   	if (stickybit || Dbl_isone_lowmantissap2(opnd3p2))
			      	Dbl_increment(opnd3p1,opnd3p2);
				}
		}
		if (Dbl_isone_hidden(opnd3p1)) dest_exponent++;
	}
	Dbl_set_mantissa(resultp1,resultp2,opnd3p1,opnd3p2);

        /*
         * Test for overflow
         */
	if (dest_exponent >= DBL_INFINITY_EXPONENT) {
                /* trap if OVERFLOWTRAP enabled */
                if (Is_overflowtrap_enabled()) {
                        /*
                         * Adjust bias of result
                         */
			Dbl_setwrapped_exponent(resultp1,dest_exponent,ovfl);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			if (inexact)
			    if (Is_inexacttrap_enabled())
				return (OVERFLOWEXCEPTION | INEXACTEXCEPTION);
			    else Set_inexactflag();
			return (OVERFLOWEXCEPTION);
                }
		inexact = TRUE;
		Set_overflowflag();
                /* set result to infinity or largest number */
		Dbl_setoverflow(resultp1,resultp2);
	}
        /*
         * Test for underflow
         */
	else if (dest_exponent <= 0) {
                /* trap if UNDERFLOWTRAP enabled */
                if (Is_underflowtrap_enabled()) {
                        /*
                         * Adjust bias of result
                         */
			Dbl_setwrapped_exponent(resultp1,dest_exponent,unfl);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
			if (inexact)
			    if (Is_inexacttrap_enabled())
				return (UNDERFLOWEXCEPTION | INEXACTEXCEPTION);
			    else Set_inexactflag();
			return (UNDERFLOWEXCEPTION);
                }

		/* Determine if should set underflow flag */
		is_tiny = TRUE;
		if (dest_exponent == 0 && inexact) {
			switch (Rounding_mode()) {
			case ROUNDPLUS:
				if (Dbl_iszero_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
                			    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDMINUS:
				if (Dbl_isone_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
                			    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDNEAREST:
				if (guardbit && (stickybit ||
				    Dbl_isone_lowmantissap2(opnd3p2))) {
				      	Dbl_increment(opnd3p1,opnd3p2);
					if (Dbl_isone_hiddenoverflow(opnd3p1))
                			    is_tiny = FALSE;
					Dbl_decrement(opnd3p1,opnd3p2);
				}
				break;
			}
		}

		/*
		 * denormalize result or set to signed zero
		 */
		stickybit = inexact;
		Dbl_denormalize(opnd3p1,opnd3p2,dest_exponent,guardbit,
		 stickybit,inexact);

		/* return zero or smallest number */
		if (inexact) {
			switch (Rounding_mode()) {
			case ROUNDPLUS:
				if (Dbl_iszero_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDMINUS:
				if (Dbl_isone_sign(resultp1)) {
					Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			case ROUNDNEAREST:
				if (guardbit && (stickybit ||
				    Dbl_isone_lowmantissap2(opnd3p2))) {
			      		Dbl_increment(opnd3p1,opnd3p2);
				}
				break;
			}
                	if (is_tiny) Set_underflowflag();
		}
		Dbl_set_exponentmantissa(resultp1,resultp2,opnd3p1,opnd3p2);
	}
	else Dbl_set_exponent(resultp1,dest_exponent);
	/* check for inexact */
	Dbl_copytoptr(resultp1,resultp2,dstptr);
	if (inexact) {
		if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
		else Set_inexactflag();
	}
	return(NOEXCEPTION);
}
Exemple #4
0
int
dbl_fmpyfadd(
	    dbl_floating_point *src1ptr,
	    dbl_floating_point *src2ptr,
	    dbl_floating_point *src3ptr,
	    unsigned int *status,
	    dbl_floating_point *dstptr)
{
	unsigned int opnd1p1, opnd1p2, opnd2p1, opnd2p2, opnd3p1, opnd3p2;
	register unsigned int tmpresp1, tmpresp2, tmpresp3, tmpresp4;
	unsigned int rightp1, rightp2, rightp3, rightp4;
	unsigned int resultp1, resultp2 = 0, resultp3 = 0, resultp4 = 0;
	register int mpy_exponent, add_exponent, count;
	boolean inexact = FALSE, is_tiny = FALSE;

	unsigned int signlessleft1, signlessright1, save;
	register int result_exponent, diff_exponent;
	int sign_save, jumpsize;
	
	Dbl_copyfromptr(src1ptr,opnd1p1,opnd1p2);
	Dbl_copyfromptr(src2ptr,opnd2p1,opnd2p2);
	Dbl_copyfromptr(src3ptr,opnd3p1,opnd3p2);

	if (Dbl_sign(opnd1p1) ^ Dbl_sign(opnd2p1)) 
		Dbl_setnegativezerop1(resultp1); 
	else Dbl_setzerop1(resultp1);

	mpy_exponent = Dbl_exponent(opnd1p1) + Dbl_exponent(opnd2p1) - DBL_BIAS;

	if (Dbl_isinfinity_exponent(opnd1p1)) {
		if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
			if (Dbl_isnotnan(opnd2p1,opnd2p2) &&
			    Dbl_isnotnan(opnd3p1,opnd3p2)) {
				if (Dbl_iszero_exponentmantissa(opnd2p1,opnd2p2)) {
					if (Is_invalidtrap_enabled())
						return(OPC_2E_INVALIDEXCEPTION);
					Set_invalidflag();
					Dbl_makequietnan(resultp1,resultp2);
					Dbl_copytoptr(resultp1,resultp2,dstptr);
					return(NOEXCEPTION);
				}
				if (Dbl_isinfinity(opnd3p1,opnd3p2) &&
				    (Dbl_sign(resultp1) ^ Dbl_sign(opnd3p1))) {
					if (Is_invalidtrap_enabled())
						return(OPC_2E_INVALIDEXCEPTION);
					Set_invalidflag();
					Dbl_makequietnan(resultp1,resultp2);
					Dbl_copytoptr(resultp1,resultp2,dstptr);
					return(NOEXCEPTION);
				}

				Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
				Dbl_copytoptr(resultp1,resultp2,dstptr);
				return(NOEXCEPTION);
			}
		}
		else {
			if (Dbl_isone_signaling(opnd1p1)) {
				
				if (Is_invalidtrap_enabled()) 
			    		return(OPC_2E_INVALIDEXCEPTION);
				
				Set_invalidflag();
				Dbl_set_quiet(opnd1p1);
			}
			else if (Dbl_is_signalingnan(opnd2p1)) {
				
				if (Is_invalidtrap_enabled())
			    		return(OPC_2E_INVALIDEXCEPTION);
				
				Set_invalidflag();
				Dbl_set_quiet(opnd2p1);
				Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
				return(NOEXCEPTION);
			}
			else if (Dbl_is_signalingnan(opnd3p1)) {
				
				if (Is_invalidtrap_enabled())
			    		return(OPC_2E_INVALIDEXCEPTION);
				
				Set_invalidflag();
				Dbl_set_quiet(opnd3p1);
				Dbl_copytoptr(opnd3p1,opnd3p2,dstptr);
				return(NOEXCEPTION);
			}
			Dbl_copytoptr(opnd1p1,opnd1p2,dstptr);
			return(NOEXCEPTION);
		}
	}

	if (Dbl_isinfinity_exponent(opnd2p1)) {
		if (Dbl_iszero_mantissa(opnd2p1,opnd2p2)) {
			if (Dbl_isnotnan(opnd3p1,opnd3p2)) {
				if (Dbl_iszero_exponentmantissa(opnd1p1,opnd1p2)) {
					if (Is_invalidtrap_enabled())
						return(OPC_2E_INVALIDEXCEPTION);
					Set_invalidflag();
					Dbl_makequietnan(opnd2p1,opnd2p2);
					Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
					return(NOEXCEPTION);
				}

				if (Dbl_isinfinity(opnd3p1,opnd3p2) &&
				    (Dbl_sign(resultp1) ^ Dbl_sign(opnd3p1))) {
					if (Is_invalidtrap_enabled())
				       		return(OPC_2E_INVALIDEXCEPTION);
				       	Set_invalidflag();
				       	Dbl_makequietnan(resultp1,resultp2);
					Dbl_copytoptr(resultp1,resultp2,dstptr);
					return(NOEXCEPTION);
				}

				Dbl_setinfinity_exponentmantissa(resultp1,resultp2);
				Dbl_copytoptr(resultp1,resultp2,dstptr);
				return(NOEXCEPTION);
			}
		}
		else {
			if (Dbl_isone_signaling(opnd2p1)) {
				
				if (Is_invalidtrap_enabled())
					return(OPC_2E_INVALIDEXCEPTION);
				
				Set_invalidflag();
				Dbl_set_quiet(opnd2p1);
			}
			else if (Dbl_is_signalingnan(opnd3p1)) {
			       	
			       	if (Is_invalidtrap_enabled())
				   		return(OPC_2E_INVALIDEXCEPTION);
			       	
			       	Set_invalidflag();
			       	Dbl_set_quiet(opnd3p1);
				Dbl_copytoptr(opnd3p1,opnd3p2,dstptr);
		       		return(NOEXCEPTION);
			}
			Dbl_copytoptr(opnd2p1,opnd2p2,dstptr);
			return(NOEXCEPTION);
		}
	}

	if (Dbl_isinfinity_exponent(opnd3p1)) {
		if (Dbl_iszero_mantissa(opnd3p1,opnd3p2)) {
			
			Dbl_copytoptr(opnd3p1,opnd3p2,dstptr);
			return(NOEXCEPTION);
		} else {
			if (Dbl_isone_signaling(opnd3p1)) {
				
				if (Is_invalidtrap_enabled())
					return(OPC_2E_INVALIDEXCEPTION);
				
				Set_invalidflag();
				Dbl_set_quiet(opnd3p1);
			}
			Dbl_copytoptr(opnd3p1,opnd3p2,dstptr);
			return(NOEXCEPTION);
		}
    	}

	if (Dbl_isnotzero_exponent(opnd1p1)) {
		
		Dbl_clear_signexponent_set_hidden(opnd1p1);
	}
	else {
		
		if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) {
			if (Dbl_iszero_exponentmantissa(opnd3p1,opnd3p2)) {
				if (Is_rounding_mode(ROUNDMINUS)) {
					Dbl_or_signs(opnd3p1,resultp1);
				} else {
					Dbl_and_signs(opnd3p1,resultp1);
				}
			}
			else if (Dbl_iszero_exponent(opnd3p1) &&
			         Is_underflowtrap_enabled()) {
                    		
                    		sign_save = Dbl_signextendedsign(opnd3p1);
				result_exponent = 0;
                    		Dbl_leftshiftby1(opnd3p1,opnd3p2);
                    		Dbl_normalize(opnd3p1,opnd3p2,result_exponent);
                    		Dbl_set_sign(opnd3p1,sign_save);
                    		Dbl_setwrapped_exponent(opnd3p1,result_exponent,
							unfl);
                    		Dbl_copytoptr(opnd3p1,opnd3p2,dstptr);
                    		
                    		return(OPC_2E_UNDERFLOWEXCEPTION);
			}
			Dbl_copytoptr(opnd3p1,opnd3p2,dstptr);
			return(NOEXCEPTION);
		}
		
		Dbl_clear_signexponent(opnd1p1);
		Dbl_leftshiftby1(opnd1p1,opnd1p2);
		Dbl_normalize(opnd1p1,opnd1p2,mpy_exponent);
	}
	
	if (Dbl_isnotzero_exponent(opnd2p1)) {
		Dbl_clear_signexponent_set_hidden(opnd2p1);
	}
	else {
		
		if (Dbl_iszero_mantissa(opnd2p1,opnd2p2)) {
			if (Dbl_iszero_exponentmantissa(opnd3p1,opnd3p2)) {
				if (Is_rounding_mode(ROUNDMINUS)) {
					Dbl_or_signs(opnd3p1,resultp1);
				} else {
					Dbl_and_signs(opnd3p1,resultp1);
				}
			}
			else if (Dbl_iszero_exponent(opnd3p1) &&
			    Is_underflowtrap_enabled()) {
                    		
                    		sign_save = Dbl_signextendedsign(opnd3p1);
				result_exponent = 0;
                    		Dbl_leftshiftby1(opnd3p1,opnd3p2);
                    		Dbl_normalize(opnd3p1,opnd3p2,result_exponent);
                    		Dbl_set_sign(opnd3p1,sign_save);
                    		Dbl_setwrapped_exponent(opnd3p1,result_exponent,
							unfl);
                    		Dbl_copytoptr(opnd3p1,opnd3p2,dstptr);
                    		
				return(OPC_2E_UNDERFLOWEXCEPTION);
			}
			Dbl_copytoptr(opnd3p1,opnd3p2,dstptr);
			return(NOEXCEPTION);
		}
		
		Dbl_clear_signexponent(opnd2p1);
		Dbl_leftshiftby1(opnd2p1,opnd2p2);
		Dbl_normalize(opnd2p1,opnd2p2,mpy_exponent);
	}

	

	Dblext_setzero(tmpresp1,tmpresp2,tmpresp3,tmpresp4);

 
	for (count = DBL_P-1; count >= 0; count -= 4) {
		Dblext_rightshiftby4(tmpresp1,tmpresp2,tmpresp3,tmpresp4);
		if (Dbit28p2(opnd1p2)) {
	 		
			Fourword_add(tmpresp1, tmpresp2, tmpresp3, tmpresp4, 
			 opnd2p1<<3 | opnd2p2>>29, opnd2p2<<3, 0, 0);
		}
		if (Dbit29p2(opnd1p2)) {
			Fourword_add(tmpresp1, tmpresp2, tmpresp3, tmpresp4,
			 opnd2p1<<2 | opnd2p2>>30, opnd2p2<<2, 0, 0);
		}
		if (Dbit30p2(opnd1p2)) {
			Fourword_add(tmpresp1, tmpresp2, tmpresp3, tmpresp4,
			 opnd2p1<<1 | opnd2p2>>31, opnd2p2<<1, 0, 0);
		}
		if (Dbit31p2(opnd1p2)) {
			Fourword_add(tmpresp1, tmpresp2, tmpresp3, tmpresp4,
			 opnd2p1, opnd2p2, 0, 0);
		}
		Dbl_rightshiftby4(opnd1p1,opnd1p2);
	}
	if (Is_dexthiddenoverflow(tmpresp1)) {
		
		mpy_exponent++;
		Dblext_rightshiftby1(tmpresp1,tmpresp2,tmpresp3,tmpresp4);
	}

	Dblext_set_sign(tmpresp1,Dbl_sign(resultp1));


	add_exponent = Dbl_exponent(opnd3p1);

	if (add_exponent == 0) {
		
		if (Dbl_iszero_mantissa(opnd3p1,opnd3p2)) {
			
			result_exponent = mpy_exponent;
			Dblext_copy(tmpresp1,tmpresp2,tmpresp3,tmpresp4,
				resultp1,resultp2,resultp3,resultp4);
			sign_save = Dbl_signextendedsign(resultp1);
			goto round;
		}

		sign_save = Dbl_signextendedsign(opnd3p1);	
		Dbl_clear_signexponent(opnd3p1);
		Dbl_leftshiftby1(opnd3p1,opnd3p2);
		Dbl_normalize(opnd3p1,opnd3p2,add_exponent);
		Dbl_set_sign(opnd3p1,sign_save);	
	} else {
		Dbl_clear_exponent_set_hidden(opnd3p1);
	}
	Dbl_copyto_dblext(opnd3p1,opnd3p2,rightp1,rightp2,rightp3,rightp4);

	Dblext_xortointp1(tmpresp1,rightp1,save);

	Dblext_copytoint_exponentmantissap1(tmpresp1,signlessleft1);
	Dblext_copytoint_exponentmantissap1(rightp1,signlessright1);
	if (mpy_exponent < add_exponent || mpy_exponent == add_exponent &&
	    Dblext_ismagnitudeless(tmpresp2,rightp2,signlessleft1,signlessright1)){
		Dblext_xorfromintp1(save,rightp1,rightp1);
		Dblext_xorfromintp1(save,tmpresp1,tmpresp1);
		Dblext_swap_lower(tmpresp2,tmpresp3,tmpresp4,
			rightp2,rightp3,rightp4);
		
		diff_exponent = add_exponent - mpy_exponent;
		result_exponent = add_exponent;
	} else {
		
		diff_exponent = mpy_exponent - add_exponent;
		result_exponent = mpy_exponent;
	}
	

	if (diff_exponent > DBLEXT_THRESHOLD) {
		diff_exponent = DBLEXT_THRESHOLD;
	}

	
	Dblext_clear_sign(rightp1);
	Dblext_right_align(rightp1,rightp2,rightp3,rightp4,
		diff_exponent);
	
	
	if ((int)save < 0) {
		Dblext_subtract(tmpresp1,tmpresp2,tmpresp3,tmpresp4,
			rightp1,rightp2,rightp3,rightp4,
			resultp1,resultp2,resultp3,resultp4);
		sign_save = Dbl_signextendedsign(resultp1);
		if (Dbl_iszero_hidden(resultp1)) {
			
			Dblext_leftshiftby1(resultp1,resultp2,resultp3,
				resultp4);

			 if(Dblext_iszero(resultp1,resultp2,resultp3,resultp4)){
				
				if (Is_rounding_mode(ROUNDMINUS))
					Dbl_setone_sign(resultp1);
				Dbl_copytoptr(resultp1,resultp2,dstptr);
				return(NOEXCEPTION);
			}
			result_exponent--;

			
			if (Dbl_isone_hidden(resultp1)) {
				
				goto round;
			}

			
			while (Dbl_iszero_hiddenhigh7mantissa(resultp1)) {
				Dblext_leftshiftby8(resultp1,resultp2,resultp3,resultp4);
				result_exponent -= 8;
			}
			
			if (Dbl_iszero_hiddenhigh3mantissa(resultp1)) {
				Dblext_leftshiftby4(resultp1,resultp2,resultp3,resultp4);
				result_exponent -= 4;
			}
			jumpsize = Dbl_hiddenhigh3mantissa(resultp1);
			if (jumpsize <= 7) switch(jumpsize) {
			case 1:
				Dblext_leftshiftby3(resultp1,resultp2,resultp3,
					resultp4);
				result_exponent -= 3;
				break;
			case 2:
			case 3:
				Dblext_leftshiftby2(resultp1,resultp2,resultp3,
					resultp4);
				result_exponent -= 2;
				break;
			case 4:
			case 5:
			case 6:
			case 7:
				Dblext_leftshiftby1(resultp1,resultp2,resultp3,
					resultp4);
				result_exponent -= 1;
				break;
			}
		} 
	
	} 
	else {
		
		Dblext_addition(tmpresp1,tmpresp2,tmpresp3,tmpresp4,
			rightp1,rightp2,rightp3,rightp4,
			resultp1,resultp2,resultp3,resultp4);
		sign_save = Dbl_signextendedsign(resultp1);
		if (Dbl_isone_hiddenoverflow(resultp1)) {
	    		
	    		Dblext_arithrightshiftby1(resultp1,resultp2,resultp3,
				resultp4);
	    		result_exponent++;
		} 
	} 

  round:
	if (result_exponent <= 0 && !Is_underflowtrap_enabled()) {
		Dblext_denormalize(resultp1,resultp2,resultp3,resultp4,
			result_exponent,is_tiny);
	}
	Dbl_set_sign(resultp1,sign_save);
	if (Dblext_isnotzero_mantissap3(resultp3) || 
	    Dblext_isnotzero_mantissap4(resultp4)) {
		inexact = TRUE;
		switch(Rounding_mode()) {
		case ROUNDNEAREST: 
			if (Dblext_isone_highp3(resultp3)) {
				
				if (Dblext_isnotzero_low31p3(resultp3) ||
				    Dblext_isnotzero_mantissap4(resultp4) ||
				    Dblext_isone_lowp2(resultp2)) {
					Dbl_increment(resultp1,resultp2);
				}
			}
	    		break;

		case ROUNDPLUS:
	    		if (Dbl_iszero_sign(resultp1)) {
				
				Dbl_increment(resultp1,resultp2);
			}
			break;
	    
		case ROUNDMINUS:
	    		if (Dbl_isone_sign(resultp1)) {
				
				Dbl_increment(resultp1,resultp2);
			}
	    
		case ROUNDZERO:;
			
		} 
		if (Dbl_isone_hiddenoverflow(resultp1)) result_exponent++;
	}
	if (result_exponent >= DBL_INFINITY_EXPONENT) {
                
                if (Is_overflowtrap_enabled()) {
                        Dbl_setwrapped_exponent(resultp1,result_exponent,ovfl);
                        Dbl_copytoptr(resultp1,resultp2,dstptr);
                        if (inexact)
                            if (Is_inexacttrap_enabled())
                                return (OPC_2E_OVERFLOWEXCEPTION |
					OPC_2E_INEXACTEXCEPTION);
                            else Set_inexactflag();
                        return (OPC_2E_OVERFLOWEXCEPTION);
                }
                inexact = TRUE;
                Set_overflowflag();
                
                Dbl_setoverflow(resultp1,resultp2);

	} else if (result_exponent <= 0) {	
		if (Is_underflowtrap_enabled()) {
                	Dbl_setwrapped_exponent(resultp1,result_exponent,unfl);
			Dbl_copytoptr(resultp1,resultp2,dstptr);
                        if (inexact)
                            if (Is_inexacttrap_enabled())
                                return (OPC_2E_UNDERFLOWEXCEPTION |
					OPC_2E_INEXACTEXCEPTION);
                            else Set_inexactflag();
	    		return(OPC_2E_UNDERFLOWEXCEPTION);
		}
		else if (inexact && is_tiny) Set_underflowflag();
	}
	else Dbl_set_exponent(resultp1,result_exponent);
	Dbl_copytoptr(resultp1,resultp2,dstptr);
	if (inexact) 
		if (Is_inexacttrap_enabled()) return(OPC_2E_INEXACTEXCEPTION);
		else Set_inexactflag();
    	return(NOEXCEPTION);
}