Re: [Qemu-devel] [PATCH v3 02/13] fpu: convert float[16/32/64]_squash_denormal to new modern style

[Richard Henderson]

On 8/13/19 1:49 PM, Alex Bennée wrote:
> +static FloatParts parts_squash_denormal(FloatParts p, float_status *status)
> +{
> +    if (p.exp == 0 && p.frac != 0) {
> +        float_raise(float_flag_input_denormal, status);
> +        p.frac = 0;
> +        p.cls = float_class_zero;
> +    }
> +
> +    return p;
> +}
> +
> +float16 float16_squash_input_denormal(float16 a, float_status *status)
> +{
> +    if (status->flush_inputs_to_zero) {
> +        FloatParts p = float16_unpack_raw(a);
> +        p = parts_squash_denormal(p, status);
> +        return float16_pack_raw(p);
> +    }
> +    return a;
> +}

Hmm.  Maybe avoid the re-pack in the likely chance that we can?

static bool parts_squash_denormal(FloatParts p, float_status *status)
{
    if (p.exp == 0 && p.frac != 0) {
        float_raise(float_flag_input_denormal, status);
        return true;
    }
    return false;
}

float16 float16_squash_input_denormal(float16 a, float_status *status)
{
    if (status->flush_inputs_to_zero) {
        FloatParts p = float16_unpack_raw(a);
        if (parts_squash_denormal(p, status)) {
            return float16_set_sign(float16_zero, p.sign);
        }
    }
    return a;
}