LXR qemu/gen-icount.h

   1/* Helpers for instruction counting code generation.  */
   2
   3static TCGArg *icount_arg;
   4static int icount_label;
   5
   6static 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
  34static 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
  43static 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
  50static 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