The gen_io_end() function is obsolete (as documented in
docs/devel/tcg-icount.rst). Where an instruction is an I/O
operation, the translator frontend should call gen_io_start()
before generating the code which does the I/O, and then
end the TB immediately after this insn.
Remove the calls to gen_io_end() in the SPARC frontend,
and ensure that the insns which were calling it end the
TB if they didn't do so already.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
target/sparc/translate.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)
diff --git a/target/sparc/translate.c b/target/sparc/translate.c
index 11de5a49631..bb70ba17deb 100644
--- a/target/sparc/translate.c
+++ b/target/sparc/translate.c
@@ -3401,7 +3401,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
tcg_temp_free_i32(r_const);
gen_store_gpr(dc, rd, cpu_dst);
if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
- gen_io_end();
+ /* I/O operations in icount mode must end the TB */
+ dc->base.is_jmp = DISAS_EXIT;
}
}
break;
@@ -3454,7 +3455,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
tcg_temp_free_i32(r_const);
gen_store_gpr(dc, rd, cpu_dst);
if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
- gen_io_end();
+ /* I/O operations in icount mode must end the TB */
+ dc->base.is_jmp = DISAS_EXIT;
}
}
break;
@@ -3588,7 +3590,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
tcg_temp_free_ptr(r_tickptr);
tcg_temp_free_i32(r_const);
if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
- gen_io_end();
+ /* I/O operations in icount mode must end the TB */
+ dc->base.is_jmp = DISAS_EXIT;
}
}
break;
@@ -4582,7 +4585,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
}
gen_helper_wrpstate(cpu_env, cpu_tmp0);
if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
- gen_io_end();
+ /* I/O ops in icount mode must end the TB */
+ dc->base.is_jmp = DISAS_EXIT;
}
dc->npc = DYNAMIC_PC;
break;
@@ -4598,7 +4602,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
}
gen_helper_wrpil(cpu_env, cpu_tmp0);
if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
- gen_io_end();
+ /* I/O ops in icount mode must end the TB */
+ dc->base.is_jmp = DISAS_EXIT;
}
break;
case 9: // cwp
@@ -4697,10 +4702,6 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
gen_helper_tick_set_limit(r_tickptr,
cpu_hstick_cmpr);
tcg_temp_free_ptr(r_tickptr);
- if (tb_cflags(dc->base.tb) &
- CF_USE_ICOUNT) {
- gen_io_end();
- }
/* End TB to handle timer interrupt */
dc->base.is_jmp = DISAS_EXIT;
}
@@ -5327,9 +5328,6 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
gen_io_start();
}
gen_helper_done(cpu_env);
- if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
- gen_io_end();
- }
goto jmp_insn;
case 1:
if (!supervisor(dc))
@@ -5340,9 +5338,6 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
gen_io_start();
}
gen_helper_retry(cpu_env);
- if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
- gen_io_end();
- }
goto jmp_insn;
default:
goto illegal_insn;
--
2.20.1
On 24/07/2021 14:49, Peter Maydell wrote:
> The gen_io_end() function is obsolete (as documented in
> docs/devel/tcg-icount.rst). Where an instruction is an I/O
> operation, the translator frontend should call gen_io_start()
> before generating the code which does the I/O, and then
> end the TB immediately after this insn.
>
> Remove the calls to gen_io_end() in the SPARC frontend,
> and ensure that the insns which were calling it end the
> TB if they didn't do so already.
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> target/sparc/translate.c | 25 ++++++++++---------------
> 1 file changed, 10 insertions(+), 15 deletions(-)
>
> diff --git a/target/sparc/translate.c b/target/sparc/translate.c
> index 11de5a49631..bb70ba17deb 100644
> --- a/target/sparc/translate.c
> +++ b/target/sparc/translate.c
> @@ -3401,7 +3401,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
> tcg_temp_free_i32(r_const);
> gen_store_gpr(dc, rd, cpu_dst);
> if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
> - gen_io_end();
> + /* I/O operations in icount mode must end the TB */
> + dc->base.is_jmp = DISAS_EXIT;
> }
> }
> break;
> @@ -3454,7 +3455,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
> tcg_temp_free_i32(r_const);
> gen_store_gpr(dc, rd, cpu_dst);
> if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
> - gen_io_end();
> + /* I/O operations in icount mode must end the TB */
> + dc->base.is_jmp = DISAS_EXIT;
> }
> }
> break;
> @@ -3588,7 +3590,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
> tcg_temp_free_ptr(r_tickptr);
> tcg_temp_free_i32(r_const);
> if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
> - gen_io_end();
> + /* I/O operations in icount mode must end the TB */
> + dc->base.is_jmp = DISAS_EXIT;
> }
> }
> break;
> @@ -4582,7 +4585,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
> }
> gen_helper_wrpstate(cpu_env, cpu_tmp0);
> if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
> - gen_io_end();
> + /* I/O ops in icount mode must end the TB */
> + dc->base.is_jmp = DISAS_EXIT;
> }
> dc->npc = DYNAMIC_PC;
> break;
> @@ -4598,7 +4602,8 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
> }
> gen_helper_wrpil(cpu_env, cpu_tmp0);
> if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
> - gen_io_end();
> + /* I/O ops in icount mode must end the TB */
> + dc->base.is_jmp = DISAS_EXIT;
> }
> break;
> case 9: // cwp
> @@ -4697,10 +4702,6 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
> gen_helper_tick_set_limit(r_tickptr,
> cpu_hstick_cmpr);
> tcg_temp_free_ptr(r_tickptr);
> - if (tb_cflags(dc->base.tb) &
> - CF_USE_ICOUNT) {
> - gen_io_end();
> - }
> /* End TB to handle timer interrupt */
> dc->base.is_jmp = DISAS_EXIT;
> }
> @@ -5327,9 +5328,6 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
> gen_io_start();
> }
> gen_helper_done(cpu_env);
> - if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
> - gen_io_end();
> - }
> goto jmp_insn;
> case 1:
> if (!supervisor(dc))
> @@ -5340,9 +5338,6 @@ static void disas_sparc_insn(DisasContext * dc, unsigned int insn)
> gen_io_start();
> }
> gen_helper_retry(cpu_env);
> - if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
> - gen_io_end();
> - }
> goto jmp_insn;
> default:
> goto illegal_insn;
>
Thanks Peter, this is something that has been in the back of my mind as a TODO for a
while but I haven't managed to get around to it. From what I can see the conversion
looks good so:
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
ATB,
Mark.
© 2016 - 2026 Red Hat, Inc.