[llvm] [InstCombine] Generalize ignoreSignBitOfZero/NaN to handle more cases (PR #141015)

[Nikita Popov via llvm-commits]

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@@ -330,6 +330,14 @@ bool isKnownNeverNaN(const Value *V, unsigned Depth, const SimplifyQuery &SQ);
 std::optional<bool> computeKnownFPSignBit(const Value *V, unsigned Depth,
                                           const SimplifyQuery &SQ);
 
+/// Return true if the sign bit of result can be ignored by the user when the
+/// result is zero.
+bool ignoreSignBitOfZero(const Use &U);
----------------
nikic wrote:

nit:
```suggestion
/// Return true if the sign bit of the value can be ignored by the user when the
/// value is zero.
bool canIgnoreSignBitOfZero(const Use &U);
```

https://github.com/llvm/llvm-project/pull/141015