Re: [PATCH v2 43/45] target/arm/vec_helper: Add gvec fp indexed multiply-and-add operations

[Richard Henderson]

On 8/28/20 11:33 AM, Peter Maydell wrote:
> +#define float16_nop(N, M, S) (M)
> +#define float32_nop(N, M, S) (M)
> +#define float64_nop(N, M, S) (M)
>  
> +DO_FMUL_IDX(gvec_fmul_idx_h, nop, float16, H2)
> +DO_FMUL_IDX(gvec_fmul_idx_s, nop, float32, H4)
> +DO_FMUL_IDX(gvec_fmul_idx_d, nop, float64, )
> +
> +/*
> + * Non-fused multiply-accumulate operations, for Neon. NB that unlike
> + * the fused ops below they assume accumulate both from and into Vd.
> + */
> +DO_FMUL_IDX(gvec_fmla_nf_idx_h, add, float16, H2)
> +DO_FMUL_IDX(gvec_fmla_nf_idx_s, add, float32, H4)
> +DO_FMUL_IDX(gvec_fmls_nf_idx_h, sub, float16, H2)
> +DO_FMUL_IDX(gvec_fmls_nf_idx_s, sub, float32, H4)
> +
> +#undef float16_nop
> +#undef float32_nop
> +#undef float64_nop

This floatN_nop stuff is pretty ugly.

Better to pass in either floatN_mul, or the floatN_muladd_nf helpers that you
added earlier.  Although I guess you're missing float64_muladd_nf so far.


r~