Do we need to maintain PrimRep.VecRep?

[Ömer Sinan Ağacan]

I have some code that does things depending on PrimReps of terms and so I have
to handle VecRep there. To understand what VecRep exactly is and how to use it I
looked at its uses, and all I can find was that we have a wired-in DataCon
`vecRepDataCon` which has a type that I thought should have VecRep PrimRep, but
when I test in GHCi I see that its PrimRep is PtrRep:

    λ> map typePrimRep (map dataConRepType (tyConDataCons runtimeRepTyCon))
    [PtrRep,PtrRep,PtrRep,PtrRep,PtrRep,PtrRep,PtrRep,PtrRep,PtrRep,PtrRep,PtrRep,PtrRep,PtrRep]

(This DataCon is not exported and only used in runtimeRepTyCon)

So I think VecRep may not be in use at the moment. Do we still need to maintain
it? What's the use case? Can anyone show me a Core term that has a type whose
PrimRep is VecRep?

Thanks..