1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
#ifndef GEN_ICOUNT_H
#define GEN_ICOUNT_H
#include "exec/exec-all.h"
#include "qemu/timer.h"
/* Helpers for instruction counting code generation. */
static TCGOp *icount_start_insn;
static inline void gen_io_start(void)
{
TCGv_i32 tmp = tcg_const_i32(1);
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;
tcg_ctx->exitreq_label = gen_new_label();
if (tb_cflags(tb) & CF_USE_ICOUNT) {
count = tcg_temp_local_new_i32();
} else {
count = tcg_temp_new_i32();
}
tcg_gen_ld_i32(count, cpu_env,
offsetof(ArchCPU, neg.icount_decr.u32) -
offsetof(ArchCPU, env));
if (tb_cflags(tb) & CF_USE_ICOUNT) {
/*
* We emit a sub with a dummy immediate argument. Keep the insn index
* of the sub so that we later (when we know the actual insn count)
* can update the argument with the actual insn count.
*/
tcg_gen_sub_i32(count, count, tcg_constant_i32(0));
icount_start_insn = tcg_last_op();
}
tcg_gen_brcondi_i32(TCG_COND_LT, count, 0, tcg_ctx->exitreq_label);
if (tb_cflags(tb) & CF_USE_ICOUNT) {
tcg_gen_st16_i32(count, cpu_env,
offsetof(ArchCPU, neg.icount_decr.u16.low) -
offsetof(ArchCPU, env));
/*
* 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);
}
static inline void gen_tb_end(const TranslationBlock *tb, int num_insns)
{
if (tb_cflags(tb) & CF_USE_ICOUNT) {
/*
* Update the num_insn immediate parameter now that we know
* the actual insn count.
*/
tcg_set_insn_param(icount_start_insn, 2,
tcgv_i32_arg(tcg_constant_i32(num_insns)));
}
gen_set_label(tcg_ctx->exitreq_label);
tcg_gen_exit_tb(tb, TB_EXIT_REQUESTED);
}
#endif
|
