Re: [Qemu-devel] [PATCH v5 27/35] target/arm: Implement SVE MOVPRFX

[Peter Maydell]

On 21 June 2018 at 02:53, Richard Henderson
<address@hidden> wrote:
> Signed-off-by: Richard Henderson <address@hidden>
> ---
>  target/arm/translate-sve.c | 60 +++++++++++++++++++++++++++++++++++++-
>  target/arm/sve.decode      |  7 +++++
>  2 files changed, 66 insertions(+), 1 deletion(-)

> +/*
> + * Move Prefix
> + *
> + * TODO: The implementation so far could handle predicated merging movprfx.
> + * The helper functions as written take an extra source register to
> + * use in the operation, but the result is only written when predication
> + * succeeds.  For unpredicated movprfx, we need to rearrange the helpers
> + * to allow the final write back to the destination to be unconditional.
> + * For predicated zering movprfz, we need to rearrange the helpers to

"zeroing". Should that be "movprfx" or is "movprfz" a thing? (the SVE
spec doesn't mention it.)

> + * allow the final write back to zero inactives.
> + *
> + * In the meantime, just emit the moves.
> + */
> +
> +static bool trans_MOVPRFX(DisasContext *s, arg_MOVPRFX *a, uint32_t insn)
> +{
> +    return do_mov_z(s, a->rd, a->rn);
> +}

A bit confusing that do_mov_z() does the sve_access_check() for us
but do_sel_z() and do_movz_zpz() do not...

> +
> +static bool trans_MOVPRFX_m(DisasContext *s, arg_rpr_esz *a, uint32_t insn)
> +{
> +    if (sve_access_check(s)) {
> +        do_sel_z(s, a->rd, a->rn, a->rd, a->pg, a->esz);
> +    }
> +    return true;
> +}
> +
> +static bool trans_MOVPRFX_z(DisasContext *s, arg_rpr_esz *a, uint32_t insn)
> +{
> +    if (sve_access_check(s)) {
> +        do_movz_zpz(s, a->rd, a->rn, a->pg, a->esz);
> +    }
> +    return true;
> +}

Reviewed-by: Peter Maydell <address@hidden>

thanks
-- PMM