[PATCH] D17080: [LAA] Allow more run-time alias checks by coercing pointer expressions to AddRecExprs

Anna Thomas via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Wed Sep 13 08:03:39 PDT 2017


anna added a comment.

Hi Silviu,

In https://reviews.llvm.org/D17080#869615, @sbaranga wrote:

> We only need to convert to an AddRec if we need to emit the runtime checks (see the comment above the original logic for computing NeedRTCheck).
>
> One example would be if we only have reads in the loop. If we convert in hasComputableBounds we end up having unnecessary versioning (at least with regards to the dependence analysis).


Thanks for the clarification.  makes sense.

> Would the current solution also work in your internal benchmark? If not it might be because something else would need the expression to be an AddRec?

Yes, I tried your patch and it works. I was just curious why we needed all the extra code rather than always checking if we could convert to an AddRec.


https://reviews.llvm.org/D17080





More information about the llvm-commits mailing list