[LLVMdev] [GSoC] Increase the coverage of Polly

Vlad Krylov krvladislav at gmail.com
Fri Apr 8 06:55:48 PDT 2011


How to feed pocc by jscop files which are made with -polly-export-jscop?


2011/4/8 ether zhhb <etherzhhb at gmail.com>:
> Hi,
>
> 2011/4/8 Vlad Krylov <krvladislav at gmail.com>:
>> Hi.
>>
>> I see that to detect scops firstly we search for regions in CFG ( by
>> RegionInfo ) and then select regions that answer some requirements (
>> in ScopDetection ). Because only affine expressions in conditions and
>> bounds are permissible, we trying to get scalar expressions into
>> affine form by AffineSCEVIterator. At present there plugs for scev
>> types Truncate, ZeroExtend, SignExtend, UDivExpr, UMaxExpr , SMaxExpr.
>> Also there are no support for wrap flags NUW, NSW, NW. It can be
>> unsafe if we doesn't provide this information in polly IR.
> Yes, if AffineSCEVIterator can iterate Truncate, ZeroExtend and
> SignExtend correctly, polly can accept much more Scops.
>>
>> So I will mainly improve AffineSCEVIterator. Now I should to show test
>> cases indicating that
>> - loops with above-listed types expressions cannot be converted to the
>> polyhedral representation
>> - wrap flags are ignored and this can bring to broken programs (in
>> fact, here I need some clarification)
>>
>> Do I understand correctly?
> I think so.
>>
>> I have some QA skills. Is Polly in need of autoconf, cmake, buildbot
>> setting up? Maybe this will be my tasks for first weeks
> Looking forward to working with you :)
>
> best regards
> ether
>



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