[PATCH] D71852: [Attributor] Reach optimistic fixpoint in AAValueSimplify when the value is constant or undef

[Hideto Ueno via Phabricator via llvm-commits]

uenoku added a comment.

In D71852#1795717 <https://reviews.llvm.org/D71852#1795717>, @baziotis wrote:

> In D71852#1795715 <https://reviews.llvm.org/D71852#1795715>, @jdoerfert wrote:
>
> > Sorry, I didn't see your comment at first.
>
>
> No problem.
>
> > `AAValueSimplify` computes the best simplified value, it is considered "assumed" as long as we cannot prove it is correct, once that happens it is "known". In case of a constant (or undef which should actually be a constant), there is not much to do as it is the most simplified version (in almost all cases), thus we know it is a correct value.
>
> Aha yes. Note that this was my initial interpretation as well, hence why I did not understand why was happening what was happening before this change (e.g. at the end of https://reviews.llvm.org/D71799#1795477).
>  But then, @uenoku's explanation regarding that "simplified" implies "changed" made me think of a different perspective. All in all, since we agree on a common statement of what `AAValueSimplified` does, everything's ok. :)


I didn't think it was useful to regard constant as a known simplified value in the beginning because you can trivially check the associated value. But anyway I agree that regarding constant as "simplified" will be more natural and concise.


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https://reviews.llvm.org/D71852