C++ StackValue::get_int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();
    }
  }
}

void vframeArrayElement::unpack_on_stack(int caller_actual_parameters,
                                         int callee_parameters,
                                         int callee_locals,
                                         frame* caller,
                                         bool is_top_frame,
                                         bool is_bottom_frame,
                                         int exec_mode) {
  JavaThread* thread = (JavaThread*) Thread::current();

  // Look at bci and decide on bcp and continuation pc
  address bcp;
  // C++ interpreter doesn't need a pc since it will figure out what to do when it
  // begins execution
  address pc;
  bool use_next_mdp = false; // true if we should use the mdp associated with the next bci
                             // rather than the one associated with bcp
  if (raw_bci() == SynchronizationEntryBCI) {
    // We are deoptimizing while hanging in prologue code for synchronized method
    bcp = method()->bcp_from(0); // first byte code
    pc  = Interpreter::deopt_entry(vtos, 0); // step = 0 since we don't skip current bytecode
  } else if (should_reexecute()) { //reexecute this bytecode
    assert(is_top_frame, "reexecute allowed only for the top frame");
    bcp = method()->bcp_from(bci());
    pc  = Interpreter::deopt_reexecute_entry(method(), bcp);
  } else {
    bcp = method()->bcp_from(bci());
    pc  = Interpreter::deopt_continue_after_entry(method(), bcp, callee_parameters, is_top_frame);
    use_next_mdp = true;
  }
  assert(Bytecodes::is_defined(*bcp), "must be a valid bytecode");

  // Monitorenter and pending exceptions:
  //
  // For Compiler2, there should be no pending exception when deoptimizing at monitorenter
  // because there is no safepoint at the null pointer check (it is either handled explicitly
  // or prior to the monitorenter) and asynchronous exceptions are not made "pending" by the
  // runtime interface for the slow case (see JRT_ENTRY_FOR_MONITORENTER).  If an asynchronous
  // exception was processed, the bytecode pointer would have to be extended one bytecode beyond
  // the monitorenter to place it in the proper exception range.
  //
  // For Compiler1, deoptimization can occur while throwing a NullPointerException at monitorenter,
  // in which case bcp should point to the monitorenter since it is within the exception's range.

  assert(*bcp != Bytecodes::_monitorenter || is_top_frame, "a _monitorenter must be a top frame");
  assert(thread->deopt_nmethod() != NULL, "nmethod should be known");
  guarantee(!(thread->deopt_nmethod()->is_compiled_by_c2() &&
              *bcp == Bytecodes::_monitorenter             &&
              exec_mode == Deoptimization::Unpack_exception),
            "shouldn't get exception during monitorenter");

  int popframe_preserved_args_size_in_bytes = 0;
  int popframe_preserved_args_size_in_words = 0;
  if (is_top_frame) {
    JvmtiThreadState *state = thread->jvmti_thread_state();
    if (JvmtiExport::can_pop_frame() &&
        (thread->has_pending_popframe() || thread->popframe_forcing_deopt_reexecution())) {
      if (thread->has_pending_popframe()) {
        // Pop top frame after deoptimization
#ifndef CC_INTERP
        pc = Interpreter::remove_activation_preserving_args_entry();
#else
        // Do an uncommon trap type entry. c++ interpreter will know
        // to pop frame and preserve the args
        pc = Interpreter::deopt_entry(vtos, 0);
        use_next_mdp = false;
#endif
      } else {
        // Reexecute invoke in top frame
        pc = Interpreter::deopt_entry(vtos, 0);
        use_next_mdp = false;
        popframe_preserved_args_size_in_bytes = in_bytes(thread->popframe_preserved_args_size());
        // Note: the PopFrame-related extension of the expression stack size is done in
        // Deoptimization::fetch_unroll_info_helper
        popframe_preserved_args_size_in_words = in_words(thread->popframe_preserved_args_size_in_words());
      }
    } else if (JvmtiExport::can_force_early_return() && state != NULL && state->is_earlyret_pending()) {
      // Force early return from top frame after deoptimization
#ifndef CC_INTERP
      pc = Interpreter::remove_activation_early_entry(state->earlyret_tos());
#else
     // TBD: Need to implement ForceEarlyReturn for CC_INTERP (ia64)
#endif
    } else {
      // Possibly override the previous pc computation of the top (youngest) frame
      switch (exec_mode) {
      case Deoptimization::Unpack_deopt:
        // use what we've got
        break;
      case Deoptimization::Unpack_exception:
        // exception is pending
        pc = SharedRuntime::raw_exception_handler_for_return_address(thread, pc);
        // [phh] We're going to end up in some handler or other, so it doesn't
        // matter what mdp we point to.  See exception_handler_for_exception()
        // in interpreterRuntime.cpp.
        break;
      case Deoptimization::Unpack_uncommon_trap:
      case Deoptimization::Unpack_reexecute:
        // redo last byte code
        pc  = Interpreter::deopt_entry(vtos, 0);
        use_next_mdp = false;
//.........这里部分代码省略.........