qemu/include/exec/gen-icount.h

   1 #ifndef GEN_ICOUNT_H
   2 #define GEN_ICOUNT_H 1
   3
   4 #include "qemu/timer.h"
   5
   6 /* Helpers for instruction counting code generation.  */
   7
   8 static TCGArg *icount_arg;
   9 static TCGLabel *icount_label;
  10 static TCGLabel *exitreq_label;
  11
  12 static inline void gen_tb_start(TranslationBlock *tb)
  13 {
  14     TCGv_i32 count, flag, imm;
  15     int i;
  16
  17     exitreq_label = gen_new_label();
  18     flag = tcg_temp_new_i32();
  19     tcg_gen_ld_i32(flag, cpu_env,
  20                    offsetof(CPUState, tcg_exit_req) - ENV_OFFSET);
  21     tcg_gen_brcondi_i32(TCG_COND_NE, flag, 0, exitreq_label);
  22     tcg_temp_free_i32(flag);
  23
  24     if (!(tb->cflags & CF_USE_ICOUNT)) {
  25         return;
  26     }
  27
  28     icount_label = gen_new_label();
  29     count = tcg_temp_local_new_i32();
  30     tcg_gen_ld_i32(count, cpu_env,
  31                    -ENV_OFFSET + offsetof(CPUState, icount_decr.u32));
  32
  33     imm = tcg_temp_new_i32();
  34     tcg_gen_movi_i32(imm, 0xdeadbeef);
  35
  36     /* This is a horrid hack to allow fixing up the value later.  */
  37     i = tcg_ctx.gen_last_op_idx;
  38     i = tcg_ctx.gen_op_buf[i].args;
  39     icount_arg = &tcg_ctx.gen_opparam_buf[i + 1];
  40
  41     tcg_gen_sub_i32(count, count, imm);
  42     tcg_temp_free_i32(imm);
  43
  44     tcg_gen_brcondi_i32(TCG_COND_LT, count, 0, icount_label);
  45     tcg_gen_st16_i32(count, cpu_env,
  46                      -ENV_OFFSET + offsetof(CPUState, icount_decr.u16.low));
  47     tcg_temp_free_i32(count);
  48 }
  49
  50 static void gen_tb_end(TranslationBlock *tb, int num_insns)
  51 {
  52     gen_set_label(exitreq_label);
  53     tcg_gen_exit_tb((uintptr_t)tb + TB_EXIT_REQUESTED);
  54
  55     if (tb->cflags & CF_USE_ICOUNT) {
  56         *icount_arg = num_insns;
  57         gen_set_label(icount_label);
  58         tcg_gen_exit_tb((uintptr_t)tb + TB_EXIT_ICOUNT_EXPIRED);
  59     }
  60
  61     /* Terminate the linked list.  */
  62     tcg_ctx.gen_op_buf[tcg_ctx.gen_last_op_idx].next = -1;
  63 }
  64
  65 static inline void gen_io_start(void)
  66 {
  67     TCGv_i32 tmp = tcg_const_i32(1);
  68     tcg_gen_st_i32(tmp, cpu_env, -ENV_OFFSET + offsetof(CPUState, can_do_io));
  69     tcg_temp_free_i32(tmp);
  70 }
  71
  72 static inline void gen_io_end(void)
  73 {
  74     TCGv_i32 tmp = tcg_const_i32(0);
  75     tcg_gen_st_i32(tmp, cpu_env, -ENV_OFFSET + offsetof(CPUState, can_do_io));
  76     tcg_temp_free_i32(tmp);
  77 }
  78
  79 #endif