[llvm] [InstCombine] Preserve the sign bit of NaN in `SimplifyDemandedUseFPClass` (PR #137287)

[Yingwei Zheng via llvm-commits]

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@@ -1959,9 +1959,11 @@ static Constant *getFPClassConstant(Type *Ty, FPClassTest Mask) {
   }
 }
 
-Value *InstCombinerImpl::SimplifyDemandedUseFPClass(
-    Value *V, const FPClassTest DemandedMask, KnownFPClass &Known,
-    unsigned Depth, Instruction *CxtI) {
+Value *InstCombinerImpl::SimplifyDemandedUseFPClass(Value *V,
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dtcxzyw wrote:

It is needed by `DemandedMask &= ~fcNan;`.


https://github.com/llvm/llvm-project/pull/137287