T20275 crashes when run with optimisations (cmmMachOpFoldM: unknown unary op: MO_WF_Bitcast W64)
```hs
{-# OPTIONS_GHC -O #-}
module T20275_opt where
import Numeric
import GHC.Float
main = do
putStrLn (showHex (castFloatToWord32 (abs (castWord32ToFloat 0xFFC00000))) "")
putStrLn (showHex (castDoubleToWord64 (abs (castWord64ToDouble 0xFFF8000000000000))) "")
```
```
error:
panic! (the 'impossible' happened)
GHC version 9.13.20250212:
cmmMachOpFoldM: unknown unary op: MO_WF_Bitcast W64
```
issue