need autofill function in view

I have some text boxes in my view like this:
<?=form_input(['name'=>'last_name','type'=>'text','style'=>'text-transform:capitalize','class'=>'form-control','placeholder'=>'Enter your last name','value'=>set_value('last_name')])?>
i have a database table 'userlogin' which has a field  'last_name'
when I am entering the value in the last_name field, i want autofill function in it with all the values from 'last_name' field in database. How do i do this?