[PATCH] D158081: [IR] Add writable attribute

[Nikita Popov via Phabricator via llvm-commits]

nikic added a comment.

Something I'm concerned about is the interaction between writable and readonly, as well as `memory(argmem: read)`. The way this is specified right now, `writable readonly` is immediate UB. And I think that's semantically correct.

However, I think it would be a good idea to make things like `writable readonly` a verifier error instead. This will make sure that passes like FuncAttrs remove the writable attribute when inferring readonly (which this patch currently fails to do). I assume we prefer having readonly over writable, as in the cases where we can infer readonly we wouldn't be interested in inserting spurious stores anyway.


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  https://reviews.llvm.org/D158081/new/

https://reviews.llvm.org/D158081