On 10.08.2018 05:01, Pavel Zbitskiy wrote:
> These instructions are provided for compatibility purposes and are
> used only by old software, in the new code BAS and BASR are preferred.
> The difference between the old and new instruction exists only in the
> 24-bit mode.
>
> Signed-off-by: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>
> ---
> target/s390x/insn-data.def | 3 +++
> target/s390x/translate.c | 33 +++++++++++++++++++++++++++++++++
> 2 files changed, 36 insertions(+)
>
> diff --git a/target/s390x/insn-data.def b/target/s390x/insn-data.def
> index 5c6f33ed9c..9c7b434fca 100644
> --- a/target/s390x/insn-data.def
> +++ b/target/s390x/insn-data.def
> @@ -102,6 +102,9 @@
> D(0x9400, NI, SI, Z, la1, i2_8u, new, 0, ni, nz64, MO_UB)
> D(0xeb54, NIY, SIY, LD, la1, i2_8u, new, 0, ni, nz64, MO_UB)
>
> +/* BRANCH AND LINK */
> + C(0x0500, BALR, RR_a, Z, 0, r2_nz, r1, 0, bal, 0)
> + C(0x4500, BAL, RX_a, Z, 0, a2, r1, 0, bal, 0)
> /* BRANCH AND SAVE */
> C(0x0d00, BASR, RR_a, Z, 0, r2_nz, r1, 0, bas, 0)
> C(0x4d00, BAS, RX_a, Z, 0, a2, r1, 0, bas, 0)
> diff --git a/target/s390x/translate.c b/target/s390x/translate.c
> index 57c03cbf58..316ff79250 100644
> --- a/target/s390x/translate.c
> +++ b/target/s390x/translate.c
> @@ -1463,6 +1463,39 @@ static DisasJumpType op_bas(DisasContext *s, DisasOps *o)
> }
> }
>
> +static void save_link_info(DisasContext *s, DisasOps *o)
> +{
> + TCGv_i64 t;
> +
> + if (s->base.tb->flags & (FLAG_MASK_32 | FLAG_MASK_64)) {
> + tcg_gen_movi_i64(o->out, pc_to_link_info(s, s->pc_tmp));
"In the 24-bit or 31-bit addressing mode, bits 0-31 of
the first-operand location remain unchanged." I think this is also right
now broken for BAS.
> + return;
> + }
> + gen_op_calc_cc(s);
> + tcg_gen_andi_i64(o->out, o->out, 0xffffffff00000000ull);
> + tcg_gen_ori_i64(o->out, o->out, ((s->ilen / 2) << 30) | s->pc_tmp);
> + t = tcg_temp_new_i64();
> + tcg_gen_shri_i64(t, psw_mask, 16);
> + tcg_gen_andi_i64(t, t, 0x0f000000);
> + tcg_gen_or_i64(o->out, o->out, t);
> + tcg_gen_extu_i32_i64(t, cc_op);
> + tcg_gen_shli_i64(t, t, 28);
> + tcg_gen_or_i64(o->out, o->out, t);
> + tcg_temp_free_i64(t);
This looks good to me (ilen really belongs to the current instruction
(not pc_tmp), which seems to be what BAL expects)
> +}
> +
> +static DisasJumpType op_bal(DisasContext *s, DisasOps *o)
> +{
> + save_link_info(s, o);
> + if (o->in2) {
> + tcg_gen_mov_i64(psw_addr, o->in2);
> + per_branch(s, false);
> + return DISAS_PC_UPDATED;
> + } else {
> + return DISAS_NEXT;
> + }
> +}
> +
> static DisasJumpType op_basi(DisasContext *s, DisasOps *o)
> {
> tcg_gen_movi_i64(o->out, pc_to_link_info(s, s->pc_tmp));
>
--
Thanks,
David / dhildenb