Re: [PATCH qemu] s390x: sck: load into a temporary not into in1

[David Hildenbrand <david@redhat.com>]

On 25.01.22 13:29, Nico Boehr wrote:
> We previously loaded into in1, but in1 is not filled during
> disassembly and hence always zero. This leads to an assertion failure:
> 
>   qemu-system-s390x: /home/nrb/qemu/include/tcg/tcg.h:654: temp_idx:
>   Assertion `n >= 0 && n < tcg_ctx->nb_temps' failed.`
> 
> Instead, load into a temporary and pass that to the helper.
> 
> This fixes the SCK test I sent here under TCG:
> <https://www.spinics.net/lists/kvm/msg265169.html>
> 
> Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
> ---
>  target/s390x/tcg/translate.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/target/s390x/tcg/translate.c b/target/s390x/tcg/translate.c
> index 46dea733571e..dc0baec5a5f4 100644
> --- a/target/s390x/tcg/translate.c
> +++ b/target/s390x/tcg/translate.c
> @@ -4290,9 +4290,16 @@ static DisasJumpType op_stcke(DisasContext *s, DisasOps *o)
>  #ifndef CONFIG_USER_ONLY
>  static DisasJumpType op_sck(DisasContext *s, DisasOps *o)
>  {
> -    tcg_gen_qemu_ld_i64(o->in1, o->addr1, get_mem_index(s), MO_TEUQ | MO_ALIGN);
> -    gen_helper_sck(cc_op, cpu_env, o->in1);
> +    TCGv_i64 t1;
> +
> +    t1 = tcg_temp_new_i64();
> +
> +    tcg_gen_qemu_ld_i64(t1, o->addr1, get_mem_index(s), MO_TEUQ | MO_ALIGN);
> +    gen_helper_sck(cc_op, cpu_env, t1);
>      set_cc_static(s);
> +
> +    tcg_temp_free_i64(t1);
> +
>      return DISAS_NEXT;
>  }
>  

I think you can actually just reuse in2_m2_64a, similar as we handle SCKC


diff --git a/target/s390x/tcg/insn-data.def b/target/s390x/tcg/insn-data.def
index f0af458aee..3a78606866 100644
--- a/target/s390x/tcg/insn-data.def
+++ b/target/s390x/tcg/insn-data.def
@@ -1317,7 +1317,7 @@
 /* SET ADDRESS SPACE CONTROL FAST */
     F(0xb279, SACF,    S,     Z,   0, a2, 0, 0, sacf, 0, IF_PRIV)
 /* SET CLOCK */
-    F(0xb204, SCK,     S,     Z,   la2, 0, 0, 0, sck, 0, IF_PRIV | IF_IO)
+    F(0xb204, SCK,     S,     Z,   0, m2_64a, 0, 0, sck, 0, IF_PRIV | IF_IO)
 /* SET CLOCK COMPARATOR */
     F(0xb206, SCKC,    S,     Z,   0, m2_64a, 0, 0, sckc, 0, IF_PRIV | IF_IO)
 /* SET CLOCK PROGRAMMABLE FIELD */
diff --git a/target/s390x/tcg/translate.c b/target/s390x/tcg/translate.c
index f180853e7a..c18011920e 100644
--- a/target/s390x/tcg/translate.c
+++ b/target/s390x/tcg/translate.c
@@ -4295,8 +4295,7 @@ static DisasJumpType op_stcke(DisasContext *s, DisasOps *o)
 #ifndef CONFIG_USER_ONLY
 static DisasJumpType op_sck(DisasContext *s, DisasOps *o)
 {
-    tcg_gen_qemu_ld_i64(o->in1, o->addr1, get_mem_index(s), MO_TEUQ | MO_ALIGN);
-    gen_helper_sck(cc_op, cpu_env, o->in1);
+    gen_helper_sck(cc_op, cpu_env, o->in2);
     set_cc_static(s);
     return DISAS_NEXT;
 }


-- 
Thanks,

David / dhildenb