MachineInstr *MI;
unsigned LoopDepth;
CopyRec(MachineInstr *mi, unsigned depth)
- : MI(mi), LoopDepth(depth) {};
+ : MI(mi), LoopDepth(depth) {}
};
class SimpleRegisterCoalescing : public MachineFunctionPass,
public:
static char ID; // Pass identifcation, replacement for typeid
- SimpleRegisterCoalescing() : MachineFunctionPass(&ID) {}
+ SimpleRegisterCoalescing() : MachineFunctionPass(ID) {}
struct InstrSlots {
enum {
bool coalesceFunction(MachineFunction &mf, RegallocQuery &) {
// This runs as an independent pass, so don't do anything.
return false;
- };
+ }
/// print - Implement the dump method.
virtual void print(raw_ostream &O, const Module* = 0) const;
/// possible to coalesce this interval, but it may be possible if other
/// things get coalesced, then it returns true by reference in 'Again'.
bool JoinCopy(CopyRec &TheCopy, bool &Again);
-
+
/// JoinIntervals - Attempt to join these two intervals. On failure, this
- /// returns false. Otherwise, if one of the intervals being joined is a
- /// physreg, this method always canonicalizes DestInt to be it. The output
- /// "SrcInt" will not have been modified, so we can use this information
- /// below to update aliases.
- bool JoinIntervals(LiveInterval &LHS, LiveInterval &RHS, bool &Swapped);
-
- /// SimpleJoin - Attempt to join the specified interval into this one. The
- /// caller of this method must guarantee that the RHS only contains a single
- /// value number and that the RHS is not defined by a copy from this
- /// interval. This returns false if the intervals are not joinable, or it
- /// joins them and returns true.
- bool SimpleJoin(LiveInterval &LHS, LiveInterval &RHS);
-
+ /// returns false. The output "SrcInt" will not have been modified, so we can
+ /// use this information below to update aliases.
+ bool JoinIntervals(CoalescerPair &CP);
+
/// Return true if the two specified registers belong to different register
/// classes. The registers may be either phys or virt regs.
bool differingRegisterClasses(unsigned RegA, unsigned RegB) const;
/// the source value number is defined by a copy from the destination reg
/// see if we can merge these two destination reg valno# into a single
/// value number, eliminating a copy.
- bool AdjustCopiesBackFrom(LiveInterval &IntA, LiveInterval &IntB,
- MachineInstr *CopyMI);
+ bool AdjustCopiesBackFrom(const CoalescerPair &CP, MachineInstr *CopyMI);
/// HasOtherReachingDefs - Return true if there are definitions of IntB
/// other than BValNo val# that can reach uses of AValno val# of IntA.
/// If the source value number is defined by a commutable instruction and
/// its other operand is coalesced to the copy dest register, see if we
/// can transform the copy into a noop by commuting the definition.
- bool RemoveCopyByCommutingDef(LiveInterval &IntA, LiveInterval &IntB,
- MachineInstr *CopyMI);
+ bool RemoveCopyByCommutingDef(const CoalescerPair &CP,MachineInstr *CopyMI);
/// TrimLiveIntervalToLastUse - If there is a last use in the same basic
/// block as the copy instruction, trim the ive interval to the last use
/// and return true.
- bool TrimLiveIntervalToLastUse(LiveIndex CopyIdx,
+ bool TrimLiveIntervalToLastUse(SlotIndex CopyIdx,
MachineBasicBlock *CopyMBB,
LiveInterval &li, const LiveRange *LR);
bool ReMaterializeTrivialDef(LiveInterval &SrcInt, unsigned DstReg,
unsigned DstSubIdx, MachineInstr *CopyMI);
- /// CanCoalesceWithImpDef - Returns true if the specified copy instruction
- /// from an implicit def to another register can be coalesced away.
- bool CanCoalesceWithImpDef(MachineInstr *CopyMI,
- LiveInterval &li, LiveInterval &ImpLi) const;
-
- /// TurnCopiesFromValNoToImpDefs - The specified value# is defined by an
- /// implicit_def and it is being removed. Turn all copies from this value#
- /// into implicit_defs.
- void TurnCopiesFromValNoToImpDefs(LiveInterval &li, VNInfo *VNI);
-
- /// isWinToJoinVRWithSrcPhysReg - Return true if it's worth while to join a
- /// a virtual destination register with physical source register.
- bool isWinToJoinVRWithSrcPhysReg(MachineInstr *CopyMI,
- MachineBasicBlock *CopyMBB,
- LiveInterval &DstInt, LiveInterval &SrcInt);
-
- /// isWinToJoinVRWithDstPhysReg - Return true if it's worth while to join a
- /// copy from a virtual source register to a physical destination register.
- bool isWinToJoinVRWithDstPhysReg(MachineInstr *CopyMI,
- MachineBasicBlock *CopyMBB,
- LiveInterval &DstInt, LiveInterval &SrcInt);
-
/// isWinToJoinCrossClass - Return true if it's profitable to coalesce
/// two virtual registers from different register classes.
- bool isWinToJoinCrossClass(unsigned LargeReg, unsigned SmallReg,
- unsigned Threshold);
-
- /// HasIncompatibleSubRegDefUse - If we are trying to coalesce a virtual
- /// register with a physical register, check if any of the virtual register
- /// operand is a sub-register use or def. If so, make sure it won't result
- /// in an illegal extract_subreg or insert_subreg instruction.
- bool HasIncompatibleSubRegDefUse(MachineInstr *CopyMI,
- unsigned VirtReg, unsigned PhysReg);
-
- /// CanJoinExtractSubRegToPhysReg - Return true if it's possible to coalesce
- /// an extract_subreg where dst is a physical register, e.g.
- /// cl = EXTRACT_SUBREG reg1024, 1
- bool CanJoinExtractSubRegToPhysReg(unsigned DstReg, unsigned SrcReg,
- unsigned SubIdx, unsigned &RealDstReg);
-
- /// CanJoinInsertSubRegToPhysReg - Return true if it's possible to coalesce
- /// an insert_subreg where src is a physical register, e.g.
- /// reg1024 = INSERT_SUBREG reg1024, c1, 0
- bool CanJoinInsertSubRegToPhysReg(unsigned DstReg, unsigned SrcReg,
- unsigned SubIdx, unsigned &RealDstReg);
-
- /// ValueLiveAt - Return true if the LiveRange pointed to by the given
- /// iterator, or any subsequent range with the same value number,
- /// is live at the given point.
- bool ValueLiveAt(LiveInterval::iterator LRItr, LiveIndex defPoint) const;
-
- /// RangeIsDefinedByCopyFromReg - Return true if the specified live range of
- /// the specified live interval is defined by a copy from the specified
- /// register.
- bool RangeIsDefinedByCopyFromReg(LiveInterval &li, LiveRange *LR,
- unsigned Reg);
+ bool isWinToJoinCrossClass(unsigned SrcReg,
+ unsigned DstReg,
+ const TargetRegisterClass *SrcRC,
+ const TargetRegisterClass *DstRC,
+ const TargetRegisterClass *NewRC);
/// UpdateRegDefsUses - Replace all defs and uses of SrcReg to DstReg and
/// update the subregister number if it is not zero. If DstReg is a
/// physical register and the existing subregister number of the def / use
/// being updated is not zero, make sure to set it to the correct physical
/// subregister.
- void UpdateRegDefsUses(unsigned SrcReg, unsigned DstReg, unsigned SubIdx);
-
- /// RemoveUnnecessaryKills - Remove kill markers that are no longer accurate
- /// due to live range lengthening as the result of coalescing.
- void RemoveUnnecessaryKills(unsigned Reg, LiveInterval &LI);
+ void UpdateRegDefsUses(const CoalescerPair &CP);
/// ShortenDeadCopyLiveRange - Shorten a live range defined by a dead copy.
/// Return true if live interval is removed.
/// it as well.
bool RemoveDeadDef(LiveInterval &li, MachineInstr *DefMI);
+ /// RemoveCopyFlag - If DstReg is no longer defined by CopyMI, clear the
+ /// VNInfo copy flag for DstReg and all aliases.
+ void RemoveCopyFlag(unsigned DstReg, const MachineInstr *CopyMI);
+
/// lastRegisterUse - Returns the last use of the specific register between
/// cycles Start and End or NULL if there are no uses.
- MachineOperand *lastRegisterUse(LiveIndex Start,
- LiveIndex End, unsigned Reg,
- LiveIndex &LastUseIdx) const;
-
- /// CalculateSpillWeights - Compute spill weights for all virtual register
- /// live intervals.
- void CalculateSpillWeights();
-
- void printRegName(unsigned reg) const;
+ MachineOperand *lastRegisterUse(SlotIndex Start, SlotIndex End,
+ unsigned Reg, SlotIndex &LastUseIdx) const;
};
} // End llvm namespace