1 /* Helpers for instruction counting code generation.  */

     2 

     3 static TCGArg *icount_arg;

     4 static int icount_label;

     5 

     6 static inline void gen_icount_start(void)

     7 {

     8     TCGv_i32 count;

     9 

    10     if (!use_icount)

    11         return;

    12 

    13     icount_label = gen_new_label();

    14     /* FIXME: This generates lousy code.  We can't use tcg_new_temp because

    15        count needs to live over the conditional branch.  To workaround this

    16        we allow the target to supply a convenient register temporary.  */

    17 #ifndef ICOUNT_TEMP

    18     count = tcg_temp_local_new_i32();

    19 #else

    20     count = ICOUNT_TEMP;

    21 #endif

    22     tcg_gen_ld_i32(count, cpu_env, offsetof(CPUState, icount_decr.u32));

    23     /* This is a horrid hack to allow fixing up the value later.  */

    24     icount_arg = gen_opparam_ptr + 1;

    25     tcg_gen_subi_i32(count, count, 0xdeadbeef);

    26 

    27     tcg_gen_brcondi_i32(TCG_COND_LT, count, 0, icount_label);

    28     tcg_gen_st16_i32(count, cpu_env, offsetof(CPUState, icount_decr.u16.low));

    29 #ifndef ICOUNT_TEMP

    30     tcg_temp_free_i32(count);

    31 #endif

    32 }

    33 

    34 static void gen_icount_end(TranslationBlock *tb, int num_insns)

    35 {

    36     if (use_icount) {

    37         *icount_arg = num_insns;

    38         gen_set_label(icount_label);

    39         tcg_gen_exit_tb((long)tb + 2);

    40     }

    41 }

    42 

    43 static void inline gen_io_start(void)

    44 {

    45     TCGv_i32 tmp = tcg_const_i32(1);

    46     tcg_gen_st_i32(tmp, cpu_env, offsetof(CPUState, can_do_io));

    47     tcg_temp_free_i32(tmp);

    48 }

    49 

    50 static inline void gen_io_end(void)

    51 {

    52     TCGv_i32 tmp = tcg_const_i32(0);

    53     tcg_gen_st_i32(tmp, cpu_env, offsetof(CPUState, can_do_io));

    54     tcg_temp_free_i32(tmp);

    55 }