From f383eb80f6823663b9b440f779083063ef55aec0 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Sat, 24 Jul 2021 14:49:02 +0100 Subject: [PATCH] tcg: Drop gen_io_end() Now we have removed all the uses of gen_io_end() from target frontends, the only callsite is inside gen_tb_start(). Inline the code there, and remove the reference to it from the documentation. While we are inlining the code, switch it to use tcg_constant_i32() so we don't have to manually create and destroy a TCG temporary. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-Id: <20210724134902.7785-3-peter.maydell@linaro.org> Signed-off-by: Mark Cave-Ayland --- docs/devel/tcg-icount.rst | 3 --- include/exec/gen-icount.h | 27 ++++++++++----------------- 2 files changed, 10 insertions(+), 20 deletions(-) diff --git a/docs/devel/tcg-icount.rst b/docs/devel/tcg-icount.rst index 8d67b6c076..50c8e8dabc 100644 --- a/docs/devel/tcg-icount.rst +++ b/docs/devel/tcg-icount.rst @@ -92,6 +92,3 @@ When the translator is handling an instruction of this kind: } * it must end the TB immediately after this instruction - -Note that some older front-ends call a "gen_io_end()" function: -this is obsolete and should not be used. diff --git a/include/exec/gen-icount.h b/include/exec/gen-icount.h index 467529d84c..610cba58fe 100644 --- a/include/exec/gen-icount.h +++ b/include/exec/gen-icount.h @@ -17,22 +17,6 @@ static inline void gen_io_start(void) tcg_temp_free_i32(tmp); } -/* - * cpu->can_do_io is cleared automatically at the beginning of - * each translation block. The cost is minimal and only paid - * for -icount, plus it would be very easy to forget doing it - * in the translator. Therefore, backends only need to call - * gen_io_start. - */ -static inline void gen_io_end(void) -{ - TCGv_i32 tmp = tcg_const_i32(0); - tcg_gen_st_i32(tmp, cpu_env, - offsetof(ArchCPU, parent_obj.can_do_io) - - offsetof(ArchCPU, env)); - tcg_temp_free_i32(tmp); -} - static inline void gen_tb_start(const TranslationBlock *tb) { TCGv_i32 count; @@ -64,7 +48,16 @@ static inline void gen_tb_start(const TranslationBlock *tb) tcg_gen_st16_i32(count, cpu_env, offsetof(ArchCPU, neg.icount_decr.u16.low) - offsetof(ArchCPU, env)); - gen_io_end(); + /* + * cpu->can_do_io is cleared automatically here at the beginning of + * each translation block. The cost is minimal and only paid for + * -icount, plus it would be very easy to forget doing it in the + * translator. Doing it here means we don't need a gen_io_end() to + * go with gen_io_start(). + */ + tcg_gen_st_i32(tcg_constant_i32(0), cpu_env, + offsetof(ArchCPU, parent_obj.can_do_io) - + offsetof(ArchCPU, env)); } tcg_temp_free_i32(count);