How to use

getFrameDescriptor

method

in

com.oracle.truffle.api.frame.VirtualFrame

@ExplodeLoop
private void clearSlots(VirtualFrame frame) {
  FrameSlot[] slots = inputSlots;
  if (slots != null) {
    if (frame.getFrameDescriptor() == sourceFrameDescriptor) {
      for (int i = 0; i < slots.length; i++) {
        frame.setObject(slots[i], null);
      }
    }
  }
}

@Override
public Object execute(VirtualFrame frame) {
  assert frameDescriptor == null || frameDescriptor == frame.getFrameDescriptor();
  assureAdopted();
  Object ret = fragment.execute(frame);
  assert checkNullOrInterop(ret);
  return ret;
}

@ExplodeLoop
private void clearSlots(VirtualFrame frame) {
  FrameSlot[] slots = inputSlots;
  if (slots != null) {
    if (frame.getFrameDescriptor() == sourceFrameDescriptor) {
      for (int i = 0; i < slots.length; i++) {
        frame.setObject(slots[i], null);
      }
    }
  }
}

@Override
public Object execute(VirtualFrame frame) {
  assert frameDescriptor == null || frameDescriptor == frame.getFrameDescriptor();
  Object ret = fragment.execute(frame);
  assert checkNullOrInterop(ret);
  return ret;
}

@ExplodeLoop
protected final Object[] getSavedInputValues(VirtualFrame frame) {
  FrameSlot[] slots = inputSlots;
  if (slots == null) {
    return EMPTY_ARRAY;
  }
  Object[] inputValues;
  if (frame.getFrameDescriptor() == sourceFrameDescriptor) {
    inputValues = new Object[slots.length];
    for (int i = 0; i < slots.length; i++) {
      try {
        inputValues[i] = frame.getObject(slots[i]);
      } catch (FrameSlotTypeException e) {
        CompilerDirectives.transferToInterpreter();
        throw new AssertionError(e);
      }
    }
  } else {
    inputValues = new Object[inputSlots.length];
  }
  return inputValues;
}

@ExplodeLoop
protected final Object[] getSavedInputValues(VirtualFrame frame) {
  FrameSlot[] slots = inputSlots;
  if (slots == null) {
    return EMPTY_ARRAY;
  }
  Object[] inputValues;
  if (frame.getFrameDescriptor() == sourceFrameDescriptor) {
    inputValues = new Object[slots.length];
    for (int i = 0; i < slots.length; i++) {
      try {
        inputValues[i] = frame.getObject(slots[i]);
      } catch (FrameSlotTypeException e) {
        CompilerDirectives.transferToInterpreter();
        throw new AssertionError(e);
      }
    }
  } else {
    inputValues = new Object[inputSlots.length];
  }
  return inputValues;
}

final void saveInputValue(VirtualFrame frame, int inputIndex, Object value) {
  verifyIndex(inputIndex);
  if (inputSlots == null) {
    CompilerDirectives.transferToInterpreterAndInvalidate();
    initializeSlots(frame);
  }
  assert sourceFrameDescriptor == frame.getFrameDescriptor() : "Unstable frame descriptor used by the language.";
  frame.setObject(inputSlots[inputIndex], value);
}

final void saveInputValue(VirtualFrame frame, int inputIndex, Object value) {
  verifyIndex(inputIndex);
  if (inputSlots == null) {
    CompilerDirectives.transferToInterpreterAndInvalidate();
    initializeSlots(frame);
  }
  assert sourceFrameDescriptor == frame.getFrameDescriptor() : "Unstable frame descriptor used by the language.";
  frame.setObject(inputSlots[inputIndex], value);
}

private void initializeSlots(VirtualFrame frame) {
  Lock lock = getLock();
  lock.lock();
  try {
    if (this.inputSlots == null) {
      if (InstrumentationHandler.TRACE) {
        InstrumentationHandler.trace("SLOTS: Adding %s save slots for binding %s%n", inputCount, getBinding().getElement());
      }
      FrameDescriptor frameDescriptor = frame.getFrameDescriptor();
      FrameSlot[] slots = new FrameSlot[inputCount];
      for (int i = 0; i < inputCount; i++) {
        int slotIndex = inputBaseIndex + i;
        slots[i] = frameDescriptor.findOrAddFrameSlot(new SavedInputValueID(getBinding(), slotIndex));
      }
      this.sourceFrameDescriptor = frameDescriptor;
      this.inputSlots = slots;
    }
  } finally {
    lock.unlock();
  }
}

private void initializeSlots(VirtualFrame frame) {
  Lock lock = getLock();
  lock.lock();
  try {
    if (this.inputSlots == null) {
      if (InstrumentationHandler.TRACE) {
        InstrumentationHandler.trace("SLOTS: Adding %s save slots for binding %s%n", inputCount, getBinding().getElement());
      }
      FrameDescriptor frameDescriptor = frame.getFrameDescriptor();
      FrameSlot[] slots = new FrameSlot[inputCount];
      for (int i = 0; i < inputCount; i++) {
        int slotIndex = inputBaseIndex + i;
        slots[i] = frameDescriptor.findOrAddFrameSlot(new SavedInputValueID(getBinding(), slotIndex));
      }
      this.sourceFrameDescriptor = frameDescriptor;
      this.inputSlots = slots;
    }
  } finally {
    lock.unlock();
  }
}

private static void addGlobalFunctions(VirtualFrame virtualFrame) {
  FrameDescriptor frameDescriptor = virtualFrame.getFrameDescriptor();
  virtualFrame.setObject(frameDescriptor.addFrameSlot("println"),
      createBuiltinFunction(PrintlnBuiltinNodeFactory.getInstance(),