they do not, by default. Some species, notably the cuttlefish, do exhibit that shape in the pupil(some types of octopus also possess a similar shape sometimes). It's known that they do perceive changes in polarization of the light, but it has more to do with the retinal structure than with the shape of the pupil. read more
I think this question should be w-shaped pupil. Octopus has a different shaped pupil. The pupil of a cuttlefish is a W shape. read more