On 6 February 2018 at 16:48, Alex Bennée <alex.ben...@linaro.org> wrote:
> We can now add float16_mul and use the common decompose and
> canonicalize functions to have a single implementation for
> float16/32/64 versions.
>
> Signed-off-by: Alex Bennée <alex.ben...@linaro.org>
> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
>
> ---
> v3
> +/*
> + * Returns the result of multiplying the floating-point values `a' and
> + * `b'. The operation is performed according to the IEC/IEEE Standard
> + * for Binary Floating-Point Arithmetic.
> + */
> +
> +static FloatParts mul_floats(FloatParts a, FloatParts b, float_status *s)
> +{
> + bool sign = a.sign ^ b.sign;
> +
> + if (a.cls == float_class_normal && b.cls == float_class_normal) {
> + uint64_t hi, lo;
> + int exp = a.exp + b.exp;
> +
> + mul64To128(a.frac, b.frac, &hi, &lo);
It seems a shame that we previously were able to use a
32x32->64 multiply for the float32 case, and now we have to
do an expensive 64x64->128 multiply regardless...
Regardless
Reviewed-by: Peter Maydell <peter.mayd...@linaro.org>
thanks
-- PMM
