Esempio n. 1
0
void LIRGenerator::do_If(If* x) {
  assert(x->number_of_sux() == 2, "inconsistency");
  ValueTag tag = x->x()->type()->tag();
  bool is_safepoint = x->is_safepoint();

  If::Condition cond = x->cond();

  LIRItem xitem(x->x(), this);
  LIRItem yitem(x->y(), this);
  LIRItem* xin = &xitem;
  LIRItem* yin = &yitem;

  if (tag == longTag) {
    // for longs, only conditions "eql", "neq", "lss", "geq" are valid;
    // mirror for other conditions
    if (cond == If::gtr || cond == If::leq) {
      cond = Instruction::mirror(cond);
      xin = &yitem;
      yin = &xitem;
    }
    xin->set_destroys_register();
  }
  xin->load_item();
  if (tag == longTag && yin->is_constant() && yin->get_jlong_constant() == 0 && (cond == If::eql || cond == If::neq)) {
    // inline long zero
    yin->dont_load_item();
  } else if (tag == longTag || tag == floatTag || tag == doubleTag) {
    // longs cannot handle constants at right side
    yin->load_item();
  } else {
    yin->dont_load_item();
  }

  // add safepoint before generating condition code so it can be recomputed
  if (x->is_safepoint()) {
    // increment backedge counter if needed
    increment_backedge_counter(state_for(x, x->state_before()), x->profiled_bci());
    __ safepoint(LIR_OprFact::illegalOpr, state_for(x, x->state_before()));
  }
  set_no_result(x);

  LIR_Opr left = xin->result();
  LIR_Opr right = yin->result();
  __ cmp(lir_cond(cond), left, right);
  // Generate branch profiling. Profiling code doesn't kill flags.
  profile_branch(x, cond);
  move_to_phi(x->state());
  if (x->x()->type()->is_float_kind()) {
    __ branch(lir_cond(cond), right->type(), x->tsux(), x->usux());
  } else {
    __ branch(lir_cond(cond), right->type(), x->tsux());
  }
  assert(x->default_sux() == x->fsux(), "wrong destination above");
  __ jump(x->default_sux());
}
void LIRGenerator::do_If(If* x) {
  assert(x->number_of_sux() == 2, "inconsistency");
  ValueTag tag = x->x()->type()->tag();
  LIRItem xitem(x->x(), this);
  LIRItem yitem(x->y(), this);
  LIRItem* xin = &xitem;
  LIRItem* yin = &yitem;
  If::Condition cond = x->cond();

  if (tag == longTag) {
    // for longs, only conditions "eql", "neq", "lss", "geq" are valid;
    // mirror for other conditions
    if (cond == If::gtr || cond == If::leq) {
      // swap inputs
      cond = Instruction::mirror(cond);
      xin = &yitem;
      yin = &xitem;
    }
    xin->set_destroys_register();
  }

  LIR_Opr left = LIR_OprFact::illegalOpr;
  LIR_Opr right = LIR_OprFact::illegalOpr;

  xin->load_item();
  left = xin->result();

  if (is_simm13(yin->result())) {
    // inline int constants which are small enough to be immediate operands
    right = LIR_OprFact::value_type(yin->value()->type());
  } else if (tag == longTag && yin->is_constant() && yin->get_jlong_constant() == 0 &&
             (cond == If::eql || cond == If::neq)) {
    // inline long zero
    right = LIR_OprFact::value_type(yin->value()->type());
  } else if (tag == objectTag && yin->is_constant() && (yin->get_jobject_constant()->is_null_object())) {
    right = LIR_OprFact::value_type(yin->value()->type());
  } else {
    yin->load_item();
    right = yin->result();
  }
  set_no_result(x);

  // add safepoint before generating condition code so it can be recomputed
  if (x->is_safepoint()) {
    // increment backedge counter if needed
    increment_backedge_counter(state_for(x, x->state_before()));

    __ safepoint(new_register(T_INT), state_for(x, x->state_before()));
  }

  __ cmp(lir_cond(cond), left, right);
  profile_branch(x, cond);
  move_to_phi(x->state());
  if (x->x()->type()->is_float_kind()) {
    __ branch(lir_cond(cond), right->type(), x->tsux(), x->usux());
  } else {
    __ branch(lir_cond(cond), right->type(), x->tsux());
  }
  assert(x->default_sux() == x->fsux(), "wrong destination above");
  __ jump(x->default_sux());
}