[llvm-commits] [pr12979][patch/rfc] Clear nsw/nuw in gvn

[Duncan Sands]

Hi Rafael,

> About TBAA, in the end Nuno analysis in the second email (using the
> lowest common ancestor)  is correct, no? Some interesting cases
>
> * Two loads from different languages: They cannot alias, so there is
> no ancestor and we will simply drop the tbaa.
> * 2 and 3 in the tree
>        0
>       / \
>     1   4
>    / \
> 2   3
>
> should produce 1. Anything that would alias 2 or 3 will alias 1 and
> that is the node that alias the least. Returning 0 for example would
> unnecessarily alias 4.

did something actually change here - I thought this is what you implemented
in your original patch?

Ciao, Duncan.