+ /// Possible outcome of a register liveness query to computeRegisterLiveness()
+ enum LivenessQueryResult {
+ LQR_Live, ///< Register is known to be live.
+ LQR_OverlappingLive, ///< Register itself is not live, but some overlapping
+ ///< register is.
+ LQR_Dead, ///< Register is known to be dead.
+ LQR_Unknown ///< Register liveness not decidable from local
+ ///< neighborhood.
+ };
+
+ /// computeRegisterLiveness - Return whether (physical) register \c Reg
+ /// has been <def>ined and not <kill>ed as of just before \c MI.
+ ///
+ /// Search is localised to a neighborhood of
+ /// \c Neighborhood instructions before (searching for defs or kills) and
+ /// Neighborhood instructions after (searching just for defs) MI.
+ ///
+ /// \c Reg must be a physical register.
+ LivenessQueryResult computeRegisterLiveness(const TargetRegisterInfo *TRI,
+ unsigned Reg, MachineInstr *MI,
+ unsigned Neighborhood=10);
+