[PATCH] D134876: [ValueTracking] Fix CannotBeOrderedLessThanZero() for fdiv (PR58046)

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/test/Transforms/InstSimplify/floating-point-compare.ll:1002
 
-; FIXME: Miscompile.
 define i1 @pr58046(i64 %arg) {
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spatel wrote:
> This wasn't just wrong...it was really, really wrong. :)
> https://alive2.llvm.org/ce/z/p4D5Bo
> 
> Worth a TODO; some missing analysis of int-to-FP casts?
It looks like our fmul zero folds currently only support FMF folds, not anything ValueTracking based: https://github.com/llvm/llvm-project/blob/8b38a2c0a55a9140115a91959326918d99bea435/llvm/lib/Analysis/InstructionSimplify.cpp#L5313-L5319


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https://reviews.llvm.org/D134876