Re: [PATCH v2 06/10 2/4] target/s390x: Use deposit to set psw_mask in save_link_info

[Richard Henderson]

On 9/9/24 16:19, Philippe Mathieu-Daudé wrote:
> From: Richard Henderson <richard.henderson@linaro.org>
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> Message-ID: <20240605215739.4758-7-richard.henderson@linaro.org>
> [PMD: Split patch, part 2/4]
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   target/s390x/tcg/translate.c | 12 ++++++++----
>   1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/target/s390x/tcg/translate.c b/target/s390x/tcg/translate.c
> index faa6d37c8e..53ec817e29 100644
> --- a/target/s390x/tcg/translate.c
> +++ b/target/s390x/tcg/translate.c
> @@ -1417,6 +1417,7 @@ static DisasJumpType op_bas(DisasContext *s, DisasOps *o)
>   
>   static void save_link_info(DisasContext *s, DisasOps *o)
>   {
> +    TCGv_i64 t1;
>       TCGv_i64 t2;
>   
>       if (s->base.tb->flags & (FLAG_MASK_32 | FLAG_MASK_64)) {
> @@ -1425,14 +1426,17 @@ static void save_link_info(DisasContext *s, DisasOps *o)
>       }
>   
>       gen_op_calc_cc(s);
> +    t1 = tcg_temp_new_i64();
>       t2 = tcg_temp_new_i64();
> +
>       tcg_gen_andi_i64(o->out, o->out, 0xffffffff00000000ull);
> +
> +    /* Shift program mask into place, garbage outside of [27:24]. */
> +    tcg_gen_shri_i64(t1, psw_mask, 16);
> +    /* Deposit pc to replace garbage bits below program mask. */
>       gen_psw_addr_disp(s, t2, s->ilen);
> -    tcg_gen_or_i64(o->out, o->out, t2);
> +    tcg_gen_deposit_i64(o->out, t1, t2, 0, 24);

This is incorrect, as you've lost the high 32-bits of out.


r~


>       tcg_gen_ori_i64(o->out, o->out, (s->ilen / 2) << 30);
> -    tcg_gen_shri_i64(t2, psw_mask, 16);
> -    tcg_gen_andi_i64(t2, t2, 0x0f000000);
> -    tcg_gen_or_i64(o->out, o->out, t2);
>       tcg_gen_extu_i32_i64(t2, cc_op);
>       tcg_gen_shli_i64(t2, t2, 28);
>       tcg_gen_or_i64(o->out, o->out, t2);