[PATCH] D14240: Allow LLE/LD and the loop versioning infrastructure to use SCEV predicates

Fri Nov 13 04:28:43 PST 2015

sbaranga added a comment.

Hi Adam,

In http://reviews.llvm.org/D14240#283209, @anemet wrote:

> I am not saying we should implement this but I'd like to think about this now before committing to a design where we'd have no way of dropping unnecessary predicates.
>
> I am not sure that we need per-dependence predicates though.  I think it needs to be per alias set.  If you have a pointer that may wrap that can now have a dependence to any of the pointers in the same alias set.  It is still OK to drop this predicate for loop distribution if all members of this alias set fall into the same partition.
>
> Where are we going to use SCEVPreds with alias checks?  Is it to try to shape a SCEV into an AddRec?

Did you get a chance to think about this? Should we start a thread on llvm-dev?

I guess this would block the addition of new SCEV predicate types..

Thanks,
Silviu

http://reviews.llvm.org/D14240