[llvm] SelectionDAG: Support nofpclass(nan/qnan/snan/nzero) in arguments (PR #130051)

[Matt Arsenault via llvm-commits]

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@@ -397,7 +397,7 @@ struct SDNodeFlags {
     Exact = 1 << 2,
     Disjoint = 1 << 3,
     NonNeg = 1 << 4,
-    NoNaNs = 1 << 5,
+    // 1 << 5 was used as NoNaNs
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arsenm wrote:

Unrelated change, shouldn't touch the fast math flags 

https://github.com/llvm/llvm-project/pull/130051