Function get_args_from_tuple 

fn get_args_from_tuple<'ll, 'tcx>(
    bx: &mut GenericBuilder<'_, 'll, FullCx<'ll, 'tcx>>,
    tuple_op: OperandRef<'tcx, &'ll Value>,
    fn_instance: Instance<'tcx>,
) -> Vec<&'ll Value>