/* _IEEE_EXPONENT_I2_D - IEEE EXPONENT returns the exponent part of the
* 128-bit argument in 16-bit integer.
*/
_f_int2
_IEEE_EXPONENT_I2_D(_f_real16 x)
{
union _ieee_ldouble {
_f_real16 ldword;
_f_real8 dbword[2];
};
#if __BYTE_ORDER == __LITTLE_ENDIAN
const int dbword_hi = 1;
const int dbword_lo = 0;
#else
const int dbword_hi = 0;
const int dbword_lo = 1;
#endif
union _ieee_double {
_f_real8 dword;
_f_int8 lword;
unsigned long long ull;
struct {
#if __BYTE_ORDER == __LITTLE_ENDIAN
unsigned int mantissa2 : IEEE_64_MANT_BTS2;
unsigned int mantissa1 : IEEE_64_MANT_BTS1;
unsigned int exponent : IEEE_64_EXPO_BITS;
unsigned int sign : 1;
#else
unsigned int sign : 1;
unsigned int exponent : IEEE_64_EXPO_BITS;
unsigned int mantissa1 : IEEE_64_MANT_BTS1;
unsigned int mantissa2 : IEEE_64_MANT_BTS2;
#endif
} parts;
};
_f_int2 iresult = 0;
switch(fp_class_l(x)) {
case FP_SNAN:
case FP_QNAN:
case FP_POS_INF:
case FP_NEG_INF:
{
/* return positive huge for NaN or infinity. */
return(HUGE_INT2_F90);
}
case FP_POS_NORM:
case FP_NEG_NORM:
{
#pragma weak logbl
return((_f_int2) logbl(x));
}
case FP_POS_DENORM:
case FP_NEG_DENORM:
{
/* return exponent from first 64-bit double. */
union _ieee_ldouble x_val;
x_val.ldword = x;
switch(fp_class_d(x_val.dbword[dbword_hi])) {
case FP_POS_NORM:
case FP_NEG_NORM:
{
union _ieee_double db_x;
db_x.dword = x_val.dbword[dbword_hi];
return((_f_int2)(db_x.parts.exponent -
IEEE_64_EXPO_BIAS));
}
case FP_POS_DENORM:
case FP_NEG_DENORM:
{
union _ieee_double db_x;
db_x.dword = x_val.dbword[dbword_hi];
db_x.ull =
IEEE_64_MANTISSA & db_x.ull;
return((_f_int2)(-IEEE_64_EXPO_BIAS -
(_leadz8(db_x.ull) +
IEEE_64_EXPO_BITS)));
}
}
}
case FP_POS_ZERO:
case FP_NEG_ZERO:
{
/* return negative huge for zero. */
return(-HUGE_INT2_F90);
}
}
return(iresult);
}
_f_int4 _FP_CLASS_I4_D(_f_real16 x)
{
#if defined(__mips) || (defined(_LITTLE_ENDIAN) && defined(__sv2))
int x_result;
x_result = fp_class_l(x);
switch(x_result) {
case FP_NEG_ZERO: {
return (FOR_K_FP_NEG_ZERO);
break;
}
case FP_POS_ZERO: {
return (FOR_K_FP_POS_ZERO);
break;
}
case FP_NEG_DENORM: {
return (FOR_K_FP_NEG_DENORM);
break;
}
case FP_POS_DENORM: {
return (FOR_K_FP_POS_DENORM);
break;
}
case FP_NEG_INF: {
return (FOR_K_FP_NEG_INF);
break;
}
case FP_POS_INF: {
return (FOR_K_FP_POS_INF);
break;
}
case FP_SNAN: {
return (FOR_K_FP_SNAN);
break;
}
case FP_QNAN: {
return (FOR_K_FP_QNAN);
break;
}
case FP_NEG_NORM: {
return (FOR_K_FP_NEG_NORM);
break;
}
case FP_POS_NORM: {
return (FOR_K_FP_POS_NORM);
break;
}
default: {
return -1;
break;
}
} /* Switch(x_result) */
#elif (defined(_CRAYIEEE) && !defined(__mips)) || defined(_SOLARIS)
#if _F_REAL16 == 1
int x_result;
union _uval_d x_val;
x_result = fpclassify(x);
x_val.dwd = x;
switch(x_result) {
case FP_ZERO: {
/* Test for pos/neg */
if(x_val.parts.sign) {
return (FOR_K_FP_NEG_ZERO);
} else {
return (FOR_K_FP_POS_ZERO);
}
break;
}
case FP_SUBNORMAL: {
/* Test for pos/neg */
if(x_val.parts.sign) {
return (FOR_K_FP_NEG_DENORM);
} else {
return (FOR_K_FP_POS_DENORM);
}
break;
}
case FP_INFINITE: {
/* Test for pos/neg */
if(x_val.parts.sign) {
return (FOR_K_FP_NEG_INF);
} else {
return (FOR_K_FP_POS_INF);
}
break;
}
case FP_NAN: {
#ifdef _CRAYT3E /* on the t3e, all NaNs are signal NaNs */
return (FOR_K_FP_SNAN);
#else
/* test for quiet/signal on others */
if(x_val.parts.q_bit) {
return (FOR_K_FP_QNAN);
} else {
return (FOR_K_FP_SNAN);
}
#endif /* #ifdef _CRAYT3E */
break;
}
case FP_NORMAL: {
/* Test for pos/neg */
if(x_val.parts.sign) {
return (FOR_K_FP_NEG_NORM);
} else {
return (FOR_K_FP_POS_NORM);
}
break;
}
default: {
return -1;
break;
}
} /* End switch(x_result); */
#endif /* #if F_REAL16 == 1 */
#elif defined(_LITTLE_ENDIAN) && !defined(__sv2)
union _uval_d x_val;
x_val.dwd = x;
if(x_val.parts.exp == 0)
{
if(x_val.parts.up1 == 0 &&
x_val.parts.lo1 == 0 &&
x_val.parts.q_bit == 0)
{
if(x_val.parts.sign)
return (FOR_K_FP_NEG_ZERO);
else
return (FOR_K_FP_POS_ZERO);
}
else
{
if(x_val.parts.sign)
return (FOR_K_FP_NEG_DENORM);
else
return (FOR_K_FP_POS_DENORM);
}
}
else if(x_val.parts.exp == IEEE_128_EXPO_MAX)
{
if(x_val.parts.up1 == 0 &&
x_val.parts.lo1 == 0 &&
x_val.parts.q_bit == 0)
{
if(x_val.parts.sign)
return (FOR_K_FP_NEG_INF);
else
return (FOR_K_FP_POS_INF);
}
else
{
if(x_val.parts.q_bit)
return (FOR_K_FP_QNAN);
else
return (FOR_K_FP_SNAN);
}
}
else if(x_val.parts.sign)
return (FOR_K_FP_NEG_NORM);
else
return (FOR_K_FP_POS_NORM);
#endif /* #if defined(__mips) ... #elif defined(_CRAYT3E) && defined(__mips) */
return -1;
}
