Do we need to maintain PrimRep.VecRep?

Ömer Sinan Ağacan omeragacan at
Tue Jun 7 15:08:08 UTC 2016

Thanks, I can see the TyCons with VecReps there.. but I still can't see how the
terms are constructed? Can you show me some example programs, or functions in
the compiler, that generate vector terms? (e.g. terms with types with VecReps)

2016-06-07 10:48 GMT-04:00 Geoffrey Mainland <mainland at>:
> VecRep is used for vector operations. If you aren't using LLVM, you
> won't see them.
> VecRep's are generated by utils/genprimopcode/Main.hs.
> Check out compiler/stage1/build/primop-vector-tys.hs-incl in your build
> tree---should be plenty of generated VecRep's there :)
> Cheers,
> Geoff
> On 06/07/2016 05:00 AM, Ömer Sinan Ağacan wrote:
>> 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..
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