Commit 908c67fc authored by Max Filippov's avatar Max Filippov
Browse files

target-xtensa: check register window inline 



This lowers time spent in helper_window_check as reported by perf top
from ~8% to ~0.15% accelerating register-intensive tests by ~20%.

Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent 0857a06e

target-xtensa/translate.c

+25 −8
Original line number Diff line number Diff line
@@ -305,16 +305,21 @@ static void gen_left_shift_sar(DisasContext *dc, TCGv_i32 sa) 
    tcg_temp_free(tmp);

}



static void gen_advance_ccount(DisasContext *dc)

static void gen_advance_ccount_cond(DisasContext *dc)

{

    if (dc->ccount_delta > 0) {

        TCGv_i32 tmp = tcg_const_i32(dc->ccount_delta);

        dc->ccount_delta = 0;

        gen_helper_advance_ccount(cpu_env, tmp);

        tcg_temp_free(tmp);

    }

}



static void gen_advance_ccount(DisasContext *dc)

{

    gen_advance_ccount_cond(dc);

    dc->ccount_delta = 0;

}



static void reset_used_window(DisasContext *dc)

{

    dc->used_window = 0;
@@ -829,16 +834,28 @@ static void gen_window_check1(DisasContext *dc, unsigned r1) 
    }

    if (option_enabled(dc, XTENSA_OPTION_WINDOWED_REGISTER) &&

            r1 / 4 > dc->used_window) {

        int label = gen_new_label();

        TCGv_i32 ws = tcg_temp_new_i32();



        dc->used_window = r1 / 4;

        tcg_gen_deposit_i32(ws, cpu_SR[WINDOW_START], cpu_SR[WINDOW_START],

                dc->config->nareg / 4, dc->config->nareg / 4);

        tcg_gen_shr_i32(ws, ws, cpu_SR[WINDOW_BASE]);

        tcg_gen_andi_i32(ws, ws, (2 << (r1 / 4)) - 2);

        tcg_gen_brcondi_i32(TCG_COND_EQ, ws, 0, label);

        {

            TCGv_i32 pc = tcg_const_i32(dc->pc);

            TCGv_i32 w = tcg_const_i32(r1 / 4);



        dc->used_window = r1 / 4;

        gen_advance_ccount(dc);

            gen_advance_ccount_cond(dc);

            gen_helper_window_check(cpu_env, pc, w);



            tcg_temp_free(w);

            tcg_temp_free(pc);

        }

        gen_set_label(label);

        tcg_temp_free(ws);

    }

}



static void gen_window_check2(DisasContext *dc, unsigned r1, unsigned r2)