Re: [Qemu-devel] [PATCH v3 13/16] target/arm: Decode aa32 armv8.3 3-same

[Peter Maydell <peter.maydell@linaro.org>]

On 28 February 2018 at 19:31, Richard Henderson
<richard.henderson@linaro.org> wrote:
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/arm/translate.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 68 insertions(+)
>
> diff --git a/target/arm/translate.c b/target/arm/translate.c
> index 9169b6b367..45513c9d86 100644
> --- a/target/arm/translate.c
> +++ b/target/arm/translate.c
> @@ -7680,6 +7680,68 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn)
>      return 0;
>  }
>
> +/* Advanced SIMD three registers of the same length extension.
> + *  31           25    23  22    20   16   12  11   10   9    8        3     0
> + * +---------------+-----+---+-----+----+----+---+----+---+----+---------+----+
> + * | 1 1 1 1 1 1 0 | op1 | D | op2 | Vn | Vd | 1 | o3 | 0 | o4 | N Q M U | Vm |
> + * +---------------+-----+---+-----+----+----+---+----+---+----+---------+----+
> + */
> +static int disas_neon_insn_3same_ext(DisasContext *s, uint32_t insn)
> +{
> +    gen_helper_gvec_3_ptr *fn_gvec_ptr;
> +    int rd, rn, rm, rot, size, opr_sz;
> +    TCGv_ptr fpst;
> +    bool q;
> +
> +    q = extract32(insn, 6, 1);
> +    VFP_DREG_D(rd, insn);
> +    VFP_DREG_N(rn, insn);
> +    VFP_DREG_M(rm, insn);
> +    if ((rd | rn | rm) & q) {
> +        return 1;
> +    }
> +
> +    if ((insn & 0xfe200f10) == 0xfc200800) {

Slightly confusing to be re-checking bits we've already decoded,
rather than just looking at op1/op2/op3/op4/Q/U.

Anyway
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM