Commit 9e9b10c6 authored by Pavel Dovgalyuk's avatar Pavel Dovgalyuk Committed by Paolo Bonzini
Browse files

icount: remove unnecessary gen_io_end calls 



Prior patch resets can_do_io flag at the TB entry. Therefore there is no
need in resetting this flag at the end of the block.
This patch removes redundant gen_io_end calls.

Signed-off-by: default avatarPavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Message-Id: <156404429499.18669.13404064982854123855.stgit@pasha-Precision-3630-Tower>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: default avatarPavel Dovgalyuk <pavel.dovgaluk@gmail.com>
parent ba3e7926

accel/tcg/translator.c

+0 −1
Original line number Diff line number Diff line
@@ -90,7 +90,6 @@ void translator_loop(const TranslatorOps *ops, DisasContextBase *db, 
            /* Accept I/O on the last instruction.  */

            gen_io_start();

            ops->translate_insn(db, cpu);

            gen_io_end();

        } else {

            ops->translate_insn(db, cpu);

        }

include/exec/gen-icount.h

+7 −1
Original line number Diff line number Diff line
@@ -16,6 +16,13 @@ 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);
@@ -58,7 +65,6 @@ static inline void gen_tb_start(TranslationBlock *tb) 
        tcg_gen_st16_i32(count, cpu_env,

                         offsetof(ArchCPU, neg.icount_decr.u16.low) -

                         offsetof(ArchCPU, env));

        /* Disable I/O by default */

        gen_io_end();

    }

target/alpha/translate.c

+0 −2
Original line number Diff line number Diff line
@@ -1332,7 +1332,6 @@ static DisasJumpType gen_mfpr(DisasContext *ctx, TCGv va, int regno) 
        if (use_icount) {

            gen_io_start();

            helper(va);

            gen_io_end();

            return DISAS_PC_STALE;

        } else {

            helper(va);
@@ -2398,7 +2397,6 @@ static DisasJumpType translate_one(DisasContext *ctx, uint32_t insn) 
            if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) {

                gen_io_start();

                gen_helper_load_pcc(va, cpu_env);

                gen_io_end();

                ret = DISAS_PC_STALE;

            } else {

                gen_helper_load_pcc(va, cpu_env);

target/arm/translate-a64.c

+0 −4
Original line number Diff line number Diff line
@@ -1775,7 +1775,6 @@ static void handle_sys(DisasContext *s, uint32_t insn, bool isread, 


    if ((tb_cflags(s->base.tb) & CF_USE_ICOUNT) && (ri->type & ARM_CP_IO)) {

        /* I/O operations must end the TB here (whether read or write) */

        gen_io_end();

        s->base.is_jmp = DISAS_UPDATE;

    } else if (!isread && !(ri->type & ARM_CP_SUPPRESS_TB_END)) {

        /* We default to ending the TB on a coprocessor register write,
@@ -2084,9 +2083,6 @@ static void disas_uncond_b_reg(DisasContext *s, uint32_t insn) 


        gen_helper_exception_return(cpu_env, dst);

        tcg_temp_free_i64(dst);

        if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {

            gen_io_end();

        }

        /* Must exit loop to check un-masked IRQs */

        s->base.is_jmp = DISAS_EXIT;

        return;

target/arm/translate.c

+0 −7
Original line number Diff line number Diff line
@@ -3213,9 +3213,6 @@ static void gen_rfe(DisasContext *s, TCGv_i32 pc, TCGv_i32 cpsr) 
        gen_io_start();

    }

    gen_helper_cpsr_write_eret(cpu_env, cpsr);

    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {

        gen_io_end();

    }

    tcg_temp_free_i32(cpsr);

    /* Must exit loop to check un-masked IRQs */

    s->base.is_jmp = DISAS_EXIT;
@@ -7303,7 +7300,6 @@ static int disas_coproc_insn(DisasContext *s, uint32_t insn) 


        if ((tb_cflags(s->base.tb) & CF_USE_ICOUNT) && (ri->type & ARM_CP_IO)) {

            /* I/O operations must end the TB here (whether read or write) */

            gen_io_end();

            gen_lookup_tb(s);

        } else if (!isread && !(ri->type & ARM_CP_SUPPRESS_TB_END)) {

            /* We default to ending the TB on a coprocessor register write,
@@ -9163,9 +9159,6 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn) 
                        gen_io_start();

                    }

                    gen_helper_cpsr_write_eret(cpu_env, tmp);

                    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {

                        gen_io_end();

                    }

                    tcg_temp_free_i32(tmp);

                    /* Must exit loop to check un-masked IRQs */

                    s->base.is_jmp = DISAS_EXIT;