fpu/softfloat: Introduce parts_is_snan_frac

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2018-05-10 12:45:29 -07:00
parent 94933df0e5
commit 298b468e43
2 changed files with 17 additions and 10 deletions

View file

@ -86,6 +86,21 @@ this code that are retained.
#define NO_SIGNALING_NANS 1
#endif
/*----------------------------------------------------------------------------
| For the deconstructed floating-point with fraction FRAC, return true
| if the fraction represents a signalling NaN; otherwise false.
*----------------------------------------------------------------------------*/
static bool parts_is_snan_frac(uint64_t frac, float_status *status)
{
#ifdef NO_SIGNALING_NANS
return false;
#else
flag msb = extract64(frac, DECOMPOSED_BINARY_POINT - 1, 1);
return msb == status->snan_bit_is_one;
#endif
}
/*----------------------------------------------------------------------------
| The pattern for a default generated half-precision NaN.
*----------------------------------------------------------------------------*/

View file

@ -331,16 +331,8 @@ static FloatParts canonicalize(FloatParts part, const FloatFmt *parm,
part.cls = float_class_inf;
} else {
part.frac <<= parm->frac_shift;
#ifdef NO_SIGNALING_NANS
part.cls = float_class_qnan;
#else
int64_t msb = part.frac << 2;
if ((msb < 0) == status->snan_bit_is_one) {
part.cls = float_class_snan;
} else {
part.cls = float_class_qnan;
}
#endif
part.cls = (parts_is_snan_frac(part.frac, status)
? float_class_snan : float_class_qnan);
}
} else if (part.exp == 0) {
if (likely(part.frac == 0)) {