1 /* Helpers for instruction counting code generation. */
2
3 static TCGArg *icount_arg;
4 static int icount_label;
5
gen_icount_start(void)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
gen_icount_end(TranslationBlock * tb,int num_insns)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
gen_io_start(void)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
gen_io_end(void)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 }
56