type HintedCmmFormal = CmmHinted CmmFormal
type HintedCmmActual = CmmHinted CmmActual
-data CmmSafety = CmmUnsafe | CmmSafe C_SRT
+data CmmSafety = CmmUnsafe | CmmSafe C_SRT | CmmInterruptible
-- | enable us to fold used registers over 'CmmActuals' and 'CmmFormals'
instance UserOfLocalRegs CmmStmt where