[PATCH] D134726: [AMDGPU][SetWavePriority] Fix dealing with MBBInfo records.

[Ivan Kosarev via Phabricator via llvm-commits]

kosarev added inline comments.


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Comment at: llvm/lib/Target/AMDGPU/AMDGPUSetWavePriority.cpp:150-152
       SuccsMayReachVMEMLoad |= MBBInfos[Succ].MayReachVMEMLoad;
       NumFollowingVALUInsts =
           std::max(NumFollowingVALUInsts, MBBInfos[Succ].NumVALUInstsAtStart);
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arsenm wrote:
> kosarev wrote:
> > These potentially invalidate `Info`.
> Doesn't this imply it's reading uncomputed values for the successors? Don't those need to be computed for this to do something sensible?
I understand where the edge to a successor is a back edge, we will examine its `MBBInfo` here before the main `post_order(&MF)` loop had a chance to compute it. Logic-wise that itself is not a problem because we ignore loops, but since such successors are new to `MBBInfos`, this invalidates `Info`.


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  https://reviews.llvm.org/D134726/new/

https://reviews.llvm.org/D134726