[PATCH] D73342: Fix EarlyCSE to intersect aliasing metadata.

[Nikita Popov via Phabricator via llvm-commits]

nikic added a comment.

In D73342#1838974 <https://reviews.llvm.org/D73342#1838974>, @jeroen.dobbelaere wrote:

> Hal Finkel provided following example on the mailing list:
>
>   int * restrict r = a;
>   ...
>   int x = noaliasing ? *r : *a;
>   
>
> This shows that the intersection of '*r' and '*a' must be taken.


So, I guess that the reasoning here is that noalias loads are speculatable and noalias violation is thus poison (not immediate UB), so we can't make inferences from one load to the other. Does that capture it?


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https://reviews.llvm.org/D73342