[PATCH] D125299: [ValueTracking] Enable -branch-on-poison-as-ub by default

[Nikita Popov via Phabricator via llvm-commits]

nikic added a comment.

In D125299#3522408 <https://reviews.llvm.org/D125299#3522408>, @fhahn wrote:

> In D125299#3522290 <https://reviews.llvm.org/D125299#3522290>, @nikic wrote:
>
>> In D125299#3503151 <https://reviews.llvm.org/D125299#3503151>, @fhahn wrote:
>>
>>> Sounds good to me in general. I think there are at least 2 known issues with SimplifyCFG & LoopUnroll introducing branches on poison/undef. Linked to https://github.com/llvm/llvm-project/issues/45489. If you know of other issues in that area it might be good to all link them to that issue, so it is easier to keep track of the outstanding issues
>>
>> ControlHeightReduction and LoopUnroll have been fixed, patches for IndVarSimplify (https://reviews.llvm.org/D124910), JumpThreading (https://reviews.llvm.org/D125869) and CodeGenPrepare (https://reviews.llvm.org/D125887) are pending.
>
> It looks like the following LoopUnroll tests still fail verification:
>
>   Failed Tests (4):
>     LLVM :: Transforms/LoopUnroll/loop-remarks.ll
>     LLVM :: Transforms/LoopUnroll/peel-loop-and-unroll.ll
>     LLVM :: Transforms/LoopUnroll/runtime-loop-multiexit-dom-verify.ll
>     LLVM :: Transforms/LoopUnroll/runtime-loop-multiple-exits.ll
>
> I still need to check what the actual issue is.

Ah, I think this is due to the branch on `lcmp.mod` that also gets introduced. I'll take a look.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D125299/new/

https://reviews.llvm.org/D125299