Beispiel #1
0
void BX_CPP_AttrRegparmN(1) BX_CPU_C::LOOPE_Jb(bxInstruction_c *i)
{
  // it is impossible to get this instruction in long mode
  BX_ASSERT(i->as64L() == 0);

  Bit32u count;

#if BX_CPU_LEVEL >= 3
  if (i->as32L())
    count = ECX;
  else
#endif
    count = CX;

  count--;
  if ((count!=0) && get_ZF()) {
    Bit32u new_EIP = EIP + (Bit32s) i->Id();
    if (i->os32L()==0) new_EIP &= 0x0000ffff;
    branch_near32(new_EIP);
    BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
  }
#if BX_INSTRUMENTATION
  else {
    BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
  }
#endif

  if (i->as32L())
    ECX--;
  else
     CX--;
}
Beispiel #2
0
  void
bx_cpu_c::JCC_Jd(BxInstruction_t *i)
{
  Boolean condition = 0;

  switch (i->b1 & 0x0f) {
    case 0x00: /* JO */ condition = get_OF(); break;
    case 0x01: /* JNO */ condition = !get_OF(); break;
    case 0x02: /* JB */ condition = get_CF(); break;
    case 0x03: /* JNB */ condition = !get_CF(); break;
    case 0x04: /* JZ */ condition = get_ZF(); break;
    case 0x05: /* JNZ */ condition = !get_ZF(); break;
    case 0x06: /* JBE */ condition = get_CF() || get_ZF(); break;
    case 0x07: /* JNBE */ condition = !get_CF() && !get_ZF(); break;
    case 0x08: /* JS */ condition = get_SF(); break;
    case 0x09: /* JNS */ condition = !get_SF(); break;
    case 0x0A: /* JP */ condition = get_PF(); break;
    case 0x0B: /* JNP */ condition = !get_PF(); break;
    case 0x0C: /* JL */ condition = get_SF() != get_OF(); break;
    case 0x0D: /* JNL */ condition = get_SF() == get_OF(); break;
    case 0x0E: /* JLE */ condition = get_ZF() || (get_SF() != get_OF());
      break;
    case 0x0F: /* JNLE */ condition = (get_SF() == get_OF()) &&
                            !get_ZF();
      break;
    }

  if (condition) {
    Bit32u new_EIP;

    new_EIP = EIP + (Bit32s) i->Id;
#if BX_CPU_LEVEL >= 2
    if (protected_mode()) {
      if ( new_EIP > bx_cpu. sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled ) {
        BX_PANIC(("jo_routine: offset outside of CS limits"));
        exception(BX_GP_EXCEPTION, 0, 0);
        }
      }
#endif
    EIP = new_EIP;
    BX_INSTR_CNEAR_BRANCH_TAKEN(new_EIP);
    revalidate_prefetch_q();
    }
#if BX_INSTRUMENTATION
  else {
    BX_INSTR_CNEAR_BRANCH_NOT_TAKEN();
    }
#endif
}
Beispiel #3
0
void BX_CPP_AttrRegparmN(1) BX_CPU_C::JCXZ_Jb(bxInstruction_c *i)
{
  // it is impossible to get this instruction in long mode
  BX_ASSERT(i->as64L() == 0);

  Bit32u temp_ECX;

  if (i->as32L())
    temp_ECX = ECX;
  else
    temp_ECX = CX;

  if (temp_ECX == 0) {
    Bit32u new_EIP = EIP + (Bit32s) i->Id();
    if (i->os32L()==0) new_EIP &= 0x0000ffff;
    branch_near32(new_EIP);
    BX_INSTR_CNEAR_BRANCH_TAKEN(BX_CPU_ID, new_EIP);
    return;
  }

  BX_INSTR_CNEAR_BRANCH_NOT_TAKEN(BX_CPU_ID);
}