On 12 May 2018 at 01:42, Richard Henderson <richard.henderson@linaro.org> wrote:
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
> fpu/softfloat-specialize.h | 15 +++++++++++++++
> fpu/softfloat.c | 12 ++----------
> 2 files changed, 17 insertions(+), 10 deletions(-)
>
> diff --git a/fpu/softfloat-specialize.h b/fpu/softfloat-specialize.h
> index 4fc9ea4ac0..515cb12cfa 100644
> --- a/fpu/softfloat-specialize.h
> +++ b/fpu/softfloat-specialize.h
> @@ -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.
> *----------------------------------------------------------------------------*/
> diff --git a/fpu/softfloat.c b/fpu/softfloat.c
> index a56d3d975b..cb68f2eb20 100644
> --- a/fpu/softfloat.c
> +++ b/fpu/softfloat.c
> @@ -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)) {
> --
> 2.17.0
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
thanks
-- PMM