[llvm] [LoopPredication] Fix division by zero in case of zero branch weights (PR #66506)

[Duncan P. N. Exon Smith via llvm-commits]

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@@ -1,12 +1,31 @@
-; XFAIL: *
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dexonsmith wrote:

I don't think we usually land failing tests in tree (unless policies have changed? I'm not doing a ton of reviewing these days...). This makes it a bit harder to comment on them in the review.

https://github.com/llvm/llvm-project/pull/66506