[PATCH] D148674: ValueTracking: Handle frem in computeKnownFPClass

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


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Comment at: llvm/lib/Analysis/ValueTracking.cpp:4659
       computeKnownFPClass(Op->getOperand(0), DemandedElts,
-                          fcNan | fcInf | fcZero |
+                          fcNan | fcInf | fcZero | fcSubnormal |
                               KnownFPClass::OrderedLessThanZeroMask,
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Is this just fixing an oversight for FDiv?


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Comment at: llvm/lib/Analysis/ValueTracking.cpp:4686
     if (KnownLHS.isKnownNever(fcNegative) && KnownRHS.isKnownNever(fcNegative))
       Known.knownNot(fcNegative);
 
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This part only works for FDiv. I can't think of anything useful you can prove about the sign of FRem.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D148674/new/

https://reviews.llvm.org/D148674