Re: [PATCH v2 4/4] target/arm: Fix tcg_gen_gvec_dup_imm vs DUP (indexed)

[Laurent Desnogues]

On Thu, May 7, 2020 at 7:23 PM Richard Henderson
<address@hidden> wrote:
>
> DUP (indexed) can duplicate 128-bit elements, so using esz
> unconditionally can assert in tcg_gen_gvec_dup_imm.
>
> Fixes: 8711e71f9cbb
> Reported-by: Laurent Desnogues <address@hidden>
> Signed-off-by: Richard Henderson <address@hidden>

Reviewed-by: Laurent Desnogues <address@hidden>
Tested-by: Laurent Desnogues <address@hidden>

I had the same fix locally.

Thanks,

Laurent


> ---
>  target/arm/translate-sve.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/target/arm/translate-sve.c b/target/arm/translate-sve.c
> index c8649283be..83614e9e70 100644
> --- a/target/arm/translate-sve.c
> +++ b/target/arm/translate-sve.c
> @@ -2044,7 +2044,11 @@ static bool trans_DUP_x(DisasContext *s, arg_DUP_x *a)
>              unsigned nofs = vec_reg_offset(s, a->rn, index, esz);
>              tcg_gen_gvec_dup_mem(esz, dofs, nofs, vsz, vsz);
>          } else {
> -            tcg_gen_gvec_dup_imm(esz, dofs, vsz, vsz, 0);
> +            /*
> +             * While dup_mem handles 128-bit elements, dup_imm does not.
> +             * Thankfully element size doesn't matter for splatting zero.
> +             */
> +            tcg_gen_gvec_dup_imm(MO_64, dofs, vsz, vsz, 0);
>          }
>      }
>      return true;
> --
> 2.20.1
>