[PATCH] D147871: ValueTracking: Implement computeKnownFPClass for sqrt

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


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Comment at: llvm/lib/Analysis/ValueTracking.cpp:4449
+
+        // Any negative value besides -0 returns a nan.
+        if (KnownSrc.isKnownNeverNaN() && KnownSrc.SignBit &&
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jcranmer-intel wrote:
> This also includes -subnormal in DAZ=preserve-sign mode.
The comment could elaborate on the preserve sign handling, but I think this is correct as is? There is a pre-existing bug in cannotBeOrderedLessThanZeroImpl for denormal handling 


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  https://reviews.llvm.org/D147871/new/

https://reviews.llvm.org/D147871