X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FTarget%2FTargetInstrInfo.h;h=4570813ba6c2b170e32838aca358513ac8465ec8;hb=f117f93f6ecda058f546e01dc4b5d9fe7827cce6;hp=ab848b0432b9d58dd5b1f529005b998ba232732b;hpb=397f4e3583b36b23047fec06b1648f0771cd6fe3;p=oota-llvm.git diff --git a/include/llvm/Target/TargetInstrInfo.h b/include/llvm/Target/TargetInstrInfo.h index ab848b0432b..4570813ba6c 100644 --- a/include/llvm/Target/TargetInstrInfo.h +++ b/include/llvm/Target/TargetInstrInfo.h @@ -14,6 +14,7 @@ #ifndef LLVM_TARGET_TARGETINSTRINFO_H #define LLVM_TARGET_TARGETINSTRINFO_H +#include "llvm/ADT/SmallSet.h" #include "llvm/MC/MCInstrInfo.h" #include "llvm/CodeGen/DFAPacketizer.h" #include "llvm/CodeGen/MachineFunction.h" @@ -27,6 +28,7 @@ class MachineMemOperand; class MachineRegisterInfo; class MDNode; class MCInst; +class MCSchedModel; class SDNode; class ScheduleHazardRecognizer; class SelectionDAG; @@ -43,8 +45,8 @@ template class SmallVectorImpl; /// TargetInstrInfo - Interface to description of machine instruction set /// class TargetInstrInfo : public MCInstrInfo { - TargetInstrInfo(const TargetInstrInfo &); // DO NOT IMPLEMENT - void operator=(const TargetInstrInfo &); // DO NOT IMPLEMENT + TargetInstrInfo(const TargetInstrInfo &) LLVM_DELETED_FUNCTION; + void operator=(const TargetInstrInfo &) LLVM_DELETED_FUNCTION; public: TargetInstrInfo(int CFSetupOpcode = -1, int CFDestroyOpcode = -1) : CallFrameSetupOpcode(CFSetupOpcode), @@ -186,14 +188,6 @@ public: const MachineInstr *Orig, const TargetRegisterInfo &TRI) const = 0; - /// scheduleTwoAddrSource - Schedule the copy / re-mat of the source of the - /// two-addrss instruction inserted by two-address pass. - virtual void scheduleTwoAddrSource(MachineInstr *SrcMI, - MachineInstr *UseMI, - const TargetRegisterInfo &TRI) const { - // Do nothing. - } - /// duplicate - Create a duplicate of the Orig instruction in MF. This is like /// MachineFunction::CloneMachineInstr(), but the target may update operands /// that are required to be unique. @@ -320,7 +314,7 @@ public: /// being executed is given by Probability, and Confidence is a measure /// of our confidence that it will be properly predicted. virtual - bool isProfitableToIfCvt(MachineBasicBlock &MBB, unsigned NumCyles, + bool isProfitableToIfCvt(MachineBasicBlock &MBB, unsigned NumCycles, unsigned ExtraPredCycles, const BranchProbability &Probability) const { return false; @@ -348,7 +342,7 @@ public: /// Probability, and Confidence is a measure of our confidence that it /// will be properly predicted. virtual bool - isProfitableToDupForIfCvt(MachineBasicBlock &MBB, unsigned NumCyles, + isProfitableToDupForIfCvt(MachineBasicBlock &MBB, unsigned NumCycles, const BranchProbability &Probability) const { return false; } @@ -369,7 +363,109 @@ public: return false; } + /// canInsertSelect - Return true if it is possible to insert a select + /// instruction that chooses between TrueReg and FalseReg based on the + /// condition code in Cond. + /// + /// When successful, also return the latency in cycles from TrueReg, + /// FalseReg, and Cond to the destination register. The Cond latency should + /// compensate for a conditional branch being removed. For example, if a + /// conditional branch has a 3 cycle latency from the condition code read, + /// and a cmov instruction has a 2 cycle latency from the condition code + /// read, CondCycles should be returned as -1. + /// + /// @param MBB Block where select instruction would be inserted. + /// @param Cond Condition returned by AnalyzeBranch. + /// @param TrueReg Virtual register to select when Cond is true. + /// @param FalseReg Virtual register to select when Cond is false. + /// @param CondCycles Latency from Cond+Branch to select output. + /// @param TrueCycles Latency from TrueReg to select output. + /// @param FalseCycles Latency from FalseReg to select output. + virtual bool canInsertSelect(const MachineBasicBlock &MBB, + const SmallVectorImpl &Cond, + unsigned TrueReg, unsigned FalseReg, + int &CondCycles, + int &TrueCycles, int &FalseCycles) const { + return false; + } + + /// insertSelect - Insert a select instruction into MBB before I that will + /// copy TrueReg to DstReg when Cond is true, and FalseReg to DstReg when + /// Cond is false. + /// + /// This function can only be called after canInsertSelect() returned true. + /// The condition in Cond comes from AnalyzeBranch, and it can be assumed + /// that the same flags or registers required by Cond are available at the + /// insertion point. + /// + /// @param MBB Block where select instruction should be inserted. + /// @param I Insertion point. + /// @param DL Source location for debugging. + /// @param DstReg Virtual register to be defined by select instruction. + /// @param Cond Condition as computed by AnalyzeBranch. + /// @param TrueReg Virtual register to copy when Cond is true. + /// @param FalseReg Virtual register to copy when Cons is false. + virtual void insertSelect(MachineBasicBlock &MBB, + MachineBasicBlock::iterator I, DebugLoc DL, + unsigned DstReg, + const SmallVectorImpl &Cond, + unsigned TrueReg, unsigned FalseReg) const { + llvm_unreachable("Target didn't implement TargetInstrInfo::insertSelect!"); + } + + /// analyzeSelect - Analyze the given select instruction, returning true if + /// it cannot be understood. It is assumed that MI->isSelect() is true. + /// + /// When successful, return the controlling condition and the operands that + /// determine the true and false result values. + /// + /// Result = SELECT Cond, TrueOp, FalseOp + /// + /// Some targets can optimize select instructions, for example by predicating + /// the instruction defining one of the operands. Such targets should set + /// Optimizable. + /// + /// @param MI Select instruction to analyze. + /// @param Cond Condition controlling the select. + /// @param TrueOp Operand number of the value selected when Cond is true. + /// @param FalseOp Operand number of the value selected when Cond is false. + /// @param Optimizable Returned as true if MI is optimizable. + /// @returns False on success. + virtual bool analyzeSelect(const MachineInstr *MI, + SmallVectorImpl &Cond, + unsigned &TrueOp, unsigned &FalseOp, + bool &Optimizable) const { + assert(MI && MI->isSelect() && "MI must be a select instruction"); + return true; + } + + /// optimizeSelect - Given a select instruction that was understood by + /// analyzeSelect and returned Optimizable = true, attempt to optimize MI by + /// merging it with one of its operands. Returns NULL on failure. + /// + /// When successful, returns the new select instruction. The client is + /// responsible for deleting MI. + /// + /// If both sides of the select can be optimized, PreferFalse is used to pick + /// a side. + /// + /// @param MI Optimizable select instruction. + /// @param PreferFalse Try to optimize FalseOp instead of TrueOp. + /// @returns Optimized instruction or NULL. + virtual MachineInstr *optimizeSelect(MachineInstr *MI, + bool PreferFalse = false) const { + // This function must be implemented if Optimizable is ever set. + llvm_unreachable("Target must implement TargetInstrInfo::optimizeSelect!"); + } + /// copyPhysReg - Emit instructions to copy a pair of physical registers. + /// + /// This function should support copies within any legal register class as + /// well as any cross-class copies created during instruction selection. + /// + /// The source and destination registers may overlap, which may require a + /// careful implementation when multiple copy instructions are required for + /// large registers. See for example the ARM target. virtual void copyPhysReg(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, DebugLoc DL, unsigned DestReg, unsigned SrcReg, @@ -623,23 +719,40 @@ public: CreateTargetPostRAHazardRecognizer(const InstrItineraryData*, const ScheduleDAG *DAG) const = 0; - /// AnalyzeCompare - For a comparison instruction, return the source register - /// in SrcReg and the value it compares against in CmpValue. Return true if - /// the comparison instruction can be analyzed. - virtual bool AnalyzeCompare(const MachineInstr *MI, - unsigned &SrcReg, int &Mask, int &Value) const { + /// analyzeCompare - For a comparison instruction, return the source registers + /// in SrcReg and SrcReg2 if having two register operands, and the value it + /// compares against in CmpValue. Return true if the comparison instruction + /// can be analyzed. + virtual bool analyzeCompare(const MachineInstr *MI, + unsigned &SrcReg, unsigned &SrcReg2, + int &Mask, int &Value) const { return false; } - /// OptimizeCompareInstr - See if the comparison instruction can be converted + /// optimizeCompareInstr - See if the comparison instruction can be converted /// into something more efficient. E.g., on ARM most instructions can set the /// flags register, obviating the need for a separate CMP. - virtual bool OptimizeCompareInstr(MachineInstr *CmpInstr, - unsigned SrcReg, int Mask, int Value, + virtual bool optimizeCompareInstr(MachineInstr *CmpInstr, + unsigned SrcReg, unsigned SrcReg2, + int Mask, int Value, const MachineRegisterInfo *MRI) const { return false; } + /// optimizeLoadInstr - Try to remove the load by folding it to a register + /// operand at the use. We fold the load instructions if and only if the + /// def and use are in the same BB. We only look at one load and see + /// whether it can be folded into MI. FoldAsLoadDefReg is the virtual register + /// defined by the load we are trying to fold. DefMI returns the machine + /// instruction that defines FoldAsLoadDefReg, and the function returns + /// the machine instruction generated due to folding. + virtual MachineInstr* optimizeLoadInstr(MachineInstr *MI, + const MachineRegisterInfo *MRI, + unsigned &FoldAsLoadDefReg, + MachineInstr *&DefMI) const { + return 0; + } + /// FoldImmediate - 'Reg' is known to be defined by a move immediate /// instruction, try to fold the immediate into the use instruction. virtual bool FoldImmediate(MachineInstr *UseMI, MachineInstr *DefMI, @@ -648,9 +761,11 @@ public: } /// getNumMicroOps - Return the number of u-operations the given machine - /// instruction will be decoded to on the target cpu. + /// instruction will be decoded to on the target cpu. The itinerary's + /// IssueWidth is the number of microops that can be dispatched each + /// cycle. An instruction with zero microops takes no dispatch resources. virtual unsigned getNumMicroOps(const InstrItineraryData *ItinData, - const MachineInstr *MI) const; + const MachineInstr *MI) const = 0; /// isZeroCost - Return true for pseudo instructions that don't consume any /// machine resources in their current form. These are common cases that the @@ -675,7 +790,7 @@ public: virtual int getOperandLatency(const InstrItineraryData *ItinData, const MachineInstr *DefMI, unsigned DefIdx, const MachineInstr *UseMI, - unsigned UseIdx) const; + unsigned UseIdx) const = 0; /// computeOperandLatency - Compute and return the latency of the given data /// dependent def and use when the operand indices are already known. @@ -686,43 +801,23 @@ public: const MachineInstr *UseMI, unsigned UseIdx, bool FindMin = false) 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 - /// one. - virtual unsigned getOutputLatency(const InstrItineraryData *ItinData, - const MachineInstr *DefMI, unsigned DefIdx, - const MachineInstr *DepMI) const { - return 1; - } - /// getInstrLatency - Compute the instruction latency of a given instruction. /// If the instruction has higher cost when predicated, it's returned via /// PredCost. virtual unsigned getInstrLatency(const InstrItineraryData *ItinData, const MachineInstr *MI, - unsigned *PredCost = 0) const; + unsigned *PredCost = 0) const = 0; 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, + unsigned defaultDefLatency(const MCSchedModel *SchedModel, const MachineInstr *DefMI) const; + int computeDefOperandLatency(const InstrItineraryData *ItinData, + const MachineInstr *DefMI, bool FindMin) const; + /// isHighLatencyDef - Return true if this opcode has high latency to its /// result. virtual bool isHighLatencyDef(int opc) const { return false; } @@ -744,7 +839,7 @@ public: /// if the target considered it 'low'. virtual bool hasLowDefLatency(const InstrItineraryData *ItinData, - const MachineInstr *DefMI, unsigned DefIdx) const; + const MachineInstr *DefMI, unsigned DefIdx) const = 0; /// verifyInstruction - Perform target specific instruction verification. virtual @@ -901,14 +996,30 @@ public: virtual bool isSchedulingBoundary(const MachineInstr *MI, const MachineBasicBlock *MBB, const MachineFunction &MF) const; - using TargetInstrInfo::getOperandLatency; + virtual int getOperandLatency(const InstrItineraryData *ItinData, SDNode *DefNode, unsigned DefIdx, SDNode *UseNode, unsigned UseIdx) const; - using TargetInstrInfo::getInstrLatency; + virtual int getInstrLatency(const InstrItineraryData *ItinData, SDNode *Node) const; + virtual unsigned getNumMicroOps(const InstrItineraryData *ItinData, + const MachineInstr *MI) const; + + virtual unsigned getInstrLatency(const InstrItineraryData *ItinData, + const MachineInstr *MI, + unsigned *PredCost = 0) const; + + virtual + bool hasLowDefLatency(const InstrItineraryData *ItinData, + const MachineInstr *DefMI, unsigned DefIdx) const; + + virtual int getOperandLatency(const InstrItineraryData *ItinData, + const MachineInstr *DefMI, unsigned DefIdx, + const MachineInstr *UseMI, + unsigned UseIdx) const; + bool usePreRAHazardRecognizer() const; virtual ScheduleHazardRecognizer *