/*ARGSUSED*/
int
dbl_fsqrt(dbl_floating_point *srcptr, dbl_floating_point *dstptr,
unsigned int *status)
{
register unsigned int srcp1, srcp2, resultp1, resultp2;
register unsigned int newbitp1, newbitp2, sump1, sump2;
register int src_exponent;
register int guardbit = false, even_exponent;
Dbl_copyfromptr(srcptr,srcp1,srcp2);
/*
* check source operand for NaN or infinity
*/
if ((src_exponent = Dbl_exponent(srcp1)) == DBL_INFINITY_EXPONENT) {
/*
* is signaling NaN?
*/
if (Dbl_isone_signaling(srcp1)) {
/* trap if INVALIDTRAP enabled */
if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
/* make NaN quiet */
Set_invalidflag();
Dbl_set_quiet(srcp1);
}
/*
* Return quiet NaN or positive infinity.
* Fall thru to negative test if negative infinity.
*/
if (Dbl_iszero_sign(srcp1) ||
Dbl_isnotzero_mantissa(srcp1,srcp2)) {
Dbl_copytoptr(srcp1,srcp2,dstptr);
return(NOEXCEPTION);
}
}
/*
* check for zero source operand
*/
if (Dbl_iszero_exponentmantissa(srcp1,srcp2)) {
Dbl_copytoptr(srcp1,srcp2,dstptr);
return(NOEXCEPTION);
}
/*
* check for negative source operand
*/
if (Dbl_isone_sign(srcp1)) {
/* trap if INVALIDTRAP enabled */
if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
/* make NaN quiet */
Set_invalidflag();
Dbl_makequietnan(srcp1,srcp2);
Dbl_copytoptr(srcp1,srcp2,dstptr);
return(NOEXCEPTION);
}
/*
* Generate result
*/
if (src_exponent > 0) {
even_exponent = Dbl_hidden(srcp1);
Dbl_clear_signexponent_set_hidden(srcp1);
}
else {
/* normalize operand */
Dbl_clear_signexponent(srcp1);
src_exponent++;
Dbl_normalize(srcp1,srcp2,src_exponent);
even_exponent = src_exponent & 1;
}
if (even_exponent) {
/* exponent is even */
/* Add comment here. Explain why odd exponent needs correction */
Dbl_leftshiftby1(srcp1,srcp2);
}
/*
* Add comment here. Explain following algorithm.
*
* Trust me, it works.
*
*/
Dbl_setzero(resultp1,resultp2);
Dbl_allp1(newbitp1) = 1 << (DBL_P - 32);
Dbl_setzero_mantissap2(newbitp2);
while (Dbl_isnotzero(newbitp1,newbitp2) && Dbl_isnotzero(srcp1,srcp2)) {
Dbl_addition(resultp1,resultp2,newbitp1,newbitp2,sump1,sump2);
if(Dbl_isnotgreaterthan(sump1,sump2,srcp1,srcp2)) {
Dbl_leftshiftby1(newbitp1,newbitp2);
/* update result */
Dbl_addition(resultp1,resultp2,newbitp1,newbitp2,
resultp1,resultp2);
Dbl_subtract(srcp1,srcp2,sump1,sump2,srcp1,srcp2);
Dbl_rightshiftby2(newbitp1,newbitp2);
}
else {
Dbl_rightshiftby1(newbitp1,newbitp2);
}
Dbl_leftshiftby1(srcp1,srcp2);
}
/* correct exponent for pre-shift */
if (even_exponent) {
Dbl_rightshiftby1(resultp1,resultp2);
}
/* check for inexact */
if (Dbl_isnotzero(srcp1,srcp2)) {
if (!even_exponent && Dbl_islessthan(resultp1,resultp2,srcp1,srcp2)) {
Dbl_increment(resultp1,resultp2);
}
guardbit = Dbl_lowmantissap2(resultp2);
Dbl_rightshiftby1(resultp1,resultp2);
/* now round result */
switch (Rounding_mode()) {
case ROUNDPLUS:
Dbl_increment(resultp1,resultp2);
break;
case ROUNDNEAREST:
/* stickybit is always true, so guardbit
* is enough to determine rounding */
if (guardbit) {
Dbl_increment(resultp1,resultp2);
}
break;
}
/* increment result exponent by 1 if mantissa overflowed */
if (Dbl_isone_hiddenoverflow(resultp1)) src_exponent+=2;
if (Is_inexacttrap_enabled()) {
Dbl_set_exponent(resultp1,
((src_exponent-DBL_BIAS)>>1)+DBL_BIAS);
Dbl_copytoptr(resultp1,resultp2,dstptr);
return(INEXACTEXCEPTION);
}
else Set_inexactflag();
}
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);
}
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);
}
