C++ StackValue::get_obj方法代码示例

void interpretedVFrame::set_locals(StackValueCollection* values) const {
  if (values == NULL || values->size() == 0) return;

  int length = method()->max_locals();
  if (method()->is_native()) {
    // If the method is native, max_locals is not telling the truth.
    // maxlocals then equals the size of parameters
    length = method()->size_of_parameters();
  }

  assert(length == values->size(), "Mismatch between actual stack format and supplied data");

  // handle locals
  for (int i = 0; i < length; i++) {
    // Find stack location
    intptr_t *addr = locals_addr_at(i);

    // Depending on oop/int put it in the right package
    StackValue *sv = values->at(i);
    assert(sv != NULL, "sanity check");
    if (sv->type() == T_OBJECT) {
      *(oop *) addr = (sv->get_obj())();
    } else {                   // integer
      *addr = sv->get_int();
    }
  }
}

void interpretedVFrame::set_locals(StackValueCollection* values) const {
  if (values == NULL || values->size() == 0) return;

  int length = method()->max_locals();
  if (method()->is_native()) {
    // If the method is native, max_locals is not telling the truth.
    // maxlocals then equals the size of parameters 
    length = method()->size_of_parameters();
  }

  assert(length == values->size(), "Mismatch between actual stack format and supplied data");

  // Get oopmap describing oops and int for current bci
  InterpreterOopMap oop_mask;
  if (TraceDeoptimization && Verbose) {
    methodHandle m_h(thread(), method());
    OopMapCache::compute_one_oop_map(m_h, bci(), &oop_mask);
  } else {
    method()->mask_for(bci(), &oop_mask);
  }

  // handle locals
  for (int i = 0; i < length; i++) {
    // Find stack location
    intptr_t *addr = locals_addr_at(i); 

    // Depending on oop/int put it in the right package
    StackValue *sv = values->at(i);
    assert(sv != NULL, "sanity check");
    if (oop_mask.is_oop(i)) { // oop value
      *(oop *) addr = (sv->get_obj())();
    } else {                   // integer
      *addr = sv->get_int();
    }
  }
}

void vframeArrayElement::fill_in(compiledVFrame* vf) {

// Copy the information from the compiled vframe to the
// interpreter frame we will be creating to replace vf

  _method = vf->method();
  _bci    = vf->raw_bci();
  _reexecute = vf->should_reexecute();

  int index;

  // Get the monitors off-stack

  GrowableArray<MonitorInfo*>* list = vf->monitors();
  if (list->is_empty()) {
    _monitors = NULL;
  } else {

    // Allocate monitor chunk
    _monitors = new MonitorChunk(list->length());
    vf->thread()->add_monitor_chunk(_monitors);

    // Migrate the BasicLocks from the stack to the monitor chunk
    for (index = 0; index < list->length(); index++) {
      MonitorInfo* monitor = list->at(index);
      assert(!monitor->owner_is_scalar_replaced(), "object should be reallocated already");
      assert(monitor->owner() == NULL || (!monitor->owner()->is_unlocked() && !monitor->owner()->has_bias_pattern()), "object must be null or locked, and unbiased");
      BasicObjectLock* dest = _monitors->at(index);
      dest->set_obj(monitor->owner());
      monitor->lock()->move_to(monitor->owner(), dest->lock());
    }
  }

  // Convert the vframe locals and expressions to off stack
  // values. Because we will not gc all oops can be converted to
  // intptr_t (i.e. a stack slot) and we are fine. This is
  // good since we are inside a HandleMark and the oops in our
  // collection would go away between packing them here and
  // unpacking them in unpack_on_stack.

  // First the locals go off-stack

  // FIXME this seems silly it creates a StackValueCollection
  // in order to get the size to then copy them and
  // convert the types to intptr_t size slots. Seems like it
  // could do it in place... Still uses less memory than the
  // old way though

  StackValueCollection *locs = vf->locals();
  _locals = new StackValueCollection(locs->size());
  for(index = 0; index < locs->size(); index++) {
    StackValue* value = locs->at(index);
    switch(value->type()) {
      case T_OBJECT:
        assert(!value->obj_is_scalar_replaced(), "object should be reallocated already");
        // preserve object type
        _locals->add( new StackValue((intptr_t) (value->get_obj()()), T_OBJECT ));
        break;
      case T_CONFLICT:
        // A dead local.  Will be initialized to null/zero.
        _locals->add( new StackValue());
        break;
      case T_INT:
        _locals->add( new StackValue(value->get_int()));
        break;
      default:
        ShouldNotReachHere();
    }
  }

  // Now the expressions off-stack
  // Same silliness as above

  StackValueCollection *exprs = vf->expressions();
  _expressions = new StackValueCollection(exprs->size());
  for(index = 0; index < exprs->size(); index++) {
    StackValue* value = exprs->at(index);
    switch(value->type()) {
      case T_OBJECT:
        assert(!value->obj_is_scalar_replaced(), "object should be reallocated already");
        // preserve object type
        _expressions->add( new StackValue((intptr_t) (value->get_obj()()), T_OBJECT ));
        break;
      case T_CONFLICT:
        // A dead stack element.  Will be initialized to null/zero.
        // This can occur when the compiler emits a state in which stack
        // elements are known to be dead (because of an imminent exception).
        _expressions->add( new StackValue());
        break;
      case T_INT:
        _expressions->add( new StackValue(value->get_int()));
        break;
      default:
        ShouldNotReachHere();
    }
  }
}