diff options
Diffstat (limited to 'include/llvm/Target/TargetInstrInfo.h')
| -rw-r--r-- | include/llvm/Target/TargetInstrInfo.h | 40 |
1 files changed, 31 insertions, 9 deletions
diff --git a/include/llvm/Target/TargetInstrInfo.h b/include/llvm/Target/TargetInstrInfo.h index 896c152..693166f 100644 --- a/include/llvm/Target/TargetInstrInfo.h +++ b/include/llvm/Target/TargetInstrInfo.h @@ -668,18 +668,36 @@ public: return Opcode <= TargetOpcode::COPY; } + virtual int getOperandLatency(const InstrItineraryData *ItinData, + SDNode *DefNode, unsigned DefIdx, + SDNode *UseNode, unsigned UseIdx) const = 0; + /// getOperandLatency - Compute and return the use operand latency of a given /// pair of def and use. /// In most cases, the static scheduling itinerary was enough to determine the /// operand latency. But it may not be possible for instructions with variable /// number of defs / uses. + /// + /// This is a raw interface to the itinerary that may be directly overriden by + /// a target. Use computeOperandLatency to get the best estimate of latency. virtual int getOperandLatency(const InstrItineraryData *ItinData, - const MachineInstr *DefMI, unsigned DefIdx, - const MachineInstr *UseMI, unsigned UseIdx) const; - - virtual int getOperandLatency(const InstrItineraryData *ItinData, - SDNode *DefNode, unsigned DefIdx, - SDNode *UseNode, unsigned UseIdx) const = 0; + const MachineInstr *DefMI, unsigned DefIdx, + const MachineInstr *UseMI, + unsigned UseIdx) const; + + /// computeOperandLatency - Compute and return the latency of the given data + /// dependent def and use. DefMI must be a valid def. UseMI may be NULL for + /// an unknown use. If the subtarget allows, this may or may not need to call + /// getOperandLatency(). + /// + /// FindMin may be set to get the minimum vs. expected latency. Minimum + /// latency is used for scheduling groups, while expected latency is for + /// instruction cost and critical path. + unsigned computeOperandLatency(const InstrItineraryData *ItinData, + const TargetRegisterInfo *TRI, + const MachineInstr *DefMI, + const MachineInstr *UseMI, + unsigned Reg, bool FindMin) const; /// getOutputLatency - Compute and return the output dependency latency of a /// a given pair of defs which both target the same register. This is usually @@ -693,13 +711,17 @@ public: /// getInstrLatency - Compute the instruction latency of a given instruction. /// If the instruction has higher cost when predicated, it's returned via /// PredCost. - virtual int getInstrLatency(const InstrItineraryData *ItinData, - const MachineInstr *MI, - unsigned *PredCost = 0) const; + virtual unsigned getInstrLatency(const InstrItineraryData *ItinData, + const MachineInstr *MI, + unsigned *PredCost = 0) const; virtual int getInstrLatency(const InstrItineraryData *ItinData, SDNode *Node) const = 0; + /// Return the default expected latency for a def based on it's opcode. + unsigned defaultDefLatency(const InstrItineraryData *ItinData, + const MachineInstr *DefMI) const; + /// isHighLatencyDef - Return true if this opcode has high latency to its /// result. virtual bool isHighLatencyDef(int opc) const { return false; } |