well in my experience the asiatics will grow quite well in shade. So will iris. But then they just don't bloom. I guess some varieties may tolerate more shade than others. if it were me, I would try digging it up gently and potting it and putting it in the sun and see if it blooms this summer-then you will know what it is. If it still doesn't bloom, just overwinter it in the pot and it should bloom next year. Of course if it isn't in your way, I'd just leave it. But if it doesn't bloom-I'd move it to sun.
