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The gen_io_end() function is obsolete (as documented in docs/devel/tcg-icount.rst).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.mayd...@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-ayl...@ilande.co.uk> ATB, Mark.
