Re: [PATCH v3 5/8] target/ppc: Implemented xvf16ger*

[Richard Henderson]

On 5/17/22 11:37, Lucas Mateus Castro(alqotel) wrote:
> +static inline float32 bfp32_negate(float32 a)
> +{
> +    if (unlikely(((a & 0x7f800000) == 0x7f800000) && (a & 0x007fffff))) {

float32_is_any_nan.

> +                    if (neg_mul) {
> +                        msum = bfp32_negate(msum);
> +                    }
> +                    if (neg_acc) {
> +                        at[i].VsrSF(j) = float32_sub(msum, aux_acc, excp_ptr);
> +                    } else {
> +                        at[i].VsrSF(j) = float32_add(msum, aux_acc, excp_ptr);
> +                    }

Hmm.  Since we're using negate once, perhaps just go ahead and use it twice.

Or go all the way with

    if (!neg_mul && !neg_acc) {
        r = float32_add(msum, aux_acc, excp_ptr);
    } else if (!neg_mul) {
        r = float32_sub(msum, aux_acc, excp_ptr);
    } else if (!neg_acc) {
        r = float32_sub(aux_acc, msum, excp_ptr);
    } else {
        r = float32_add(bfp32_neg(msum), bfp32_neg(aux_acc), excp_ptr);
    }

Otherwise, the logic seems sane.


r~