LXR 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
   8static TCGArg *icount_arg;
   9static TCGLabel *icount_label;
  10static TCGLabel *exitreq_label;
  11
  12static 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
  50static 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
  65static 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
  72static 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
  80