#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/ADT/BitVector.h"
-#include "llvm/ADT/DenseMap.h"
namespace llvm {
/// available, unset means the register is currently being used.
BitVector RegsAvailable;
- /// CurrDist - Distance from MBB entry to the current instruction MBBI.
- ///
- unsigned CurrDist;
-
- /// DistanceMap - Keep track the distance of a MI from the start of the
- /// current basic block.
- DenseMap<MachineInstr*, unsigned> DistanceMap;
-
public:
RegScavenger()
: MBB(NULL), NumPhysRegs(0), Tracking(false),
/// basic block.
void enterBasicBlock(MachineBasicBlock *mbb);
- /// forward / backward - Move the internal MBB iterator and update register
- /// states.
+ /// initRegState - allow resetting register state info for multiple
+ /// passes over/within the same function.
+ void initRegState();
+
+ /// forward - Move the internal MBB iterator and update register states.
void forward();
- void backward();
- /// forward / backward - Move the internal MBB iterator and update register
- /// states until it has processed the specific iterator.
+ /// forward - Move the internal MBB iterator and update register states until
+ /// it has processed the specific iterator.
void forward(MachineBasicBlock::iterator I) {
if (!Tracking && MBB->begin() != I) forward();
while (MBBI != I) forward();
}
- void backward(MachineBasicBlock::iterator I) {
- while (MBBI != I) backward();
- }
/// skipTo - Move the internal MBB iterator but do not update register states.
///
void skipTo(MachineBasicBlock::iterator I) { MBBI = I; }
- /// isReserved - Returns true if a register is reserved. It is never "unused".
- bool isReserved(unsigned Reg) const { return ReservedRegs[Reg]; }
-
- /// isUsed / isUsed - Test if a register is currently being used.
- ///
- bool isUsed(unsigned Reg) const { return !RegsAvailable[Reg]; }
- bool isUnused(unsigned Reg) const { return RegsAvailable[Reg]; }
-
/// getRegsUsed - return all registers currently in use in used.
void getRegsUsed(BitVector &used, bool includeReserved);
- /// setUsed / setUnused - Mark the state of one or a number of registers.
- ///
- void setUsed(unsigned Reg);
- void setUsed(BitVector &Regs) {
- RegsAvailable &= ~Regs;
- }
- void setUnused(unsigned Reg, const MachineInstr *MI);
- void setUnused(BitVector &Regs) {
- RegsAvailable |= Regs;
- }
-
- /// FindUnusedReg - Find a unused register of the specified register class
- /// from the specified set of registers. It return 0 is none is found.
- unsigned FindUnusedReg(const TargetRegisterClass *RegClass,
- const BitVector &Candidates) const;
-
/// FindUnusedReg - Find a unused register of the specified register class.
- /// Exclude callee saved registers if directed. It return 0 is none is found.
- unsigned FindUnusedReg(const TargetRegisterClass *RegClass,
- bool ExCalleeSaved = false) const;
+ /// Return 0 if none is found.
+ unsigned FindUnusedReg(const TargetRegisterClass *RegClass) const;
/// setScavengingFrameIndex / getScavengingFrameIndex - accessor and setter of
/// ScavengingFrameIndex.
return scavengeRegister(RegClass, MBBI, SPAdj);
}
+ /// setUsed - Tell the scavenger a register is used.
+ ///
+ void setUsed(unsigned Reg);
private:
- /// restoreScavengedReg - Restore scavenged by loading it back from the
- /// emergency spill slot. Mark it used.
- void restoreScavengedReg();
+ /// isReserved - Returns true if a register is reserved. It is never "unused".
+ bool isReserved(unsigned Reg) const { return ReservedRegs.test(Reg); }
+
+ /// isUsed / isUnused - Test if a register is currently being used.
+ ///
+ bool isUsed(unsigned Reg) const { return !RegsAvailable.test(Reg); }
+ bool isUnused(unsigned Reg) const { return RegsAvailable.test(Reg); }
+
+ /// isAliasUsed - Is Reg or an alias currently in use?
+ bool isAliasUsed(unsigned Reg) const;
+
+ /// setUsed / setUnused - Mark the state of one or a number of registers.
+ ///
+ void setUsed(BitVector &Regs) {
+ RegsAvailable &= ~Regs;
+ }
+ void setUnused(BitVector &Regs) {
+ RegsAvailable |= Regs;
+ }
+
+ /// Add Reg and all its sub-registers to BV.
+ void addRegWithSubRegs(BitVector &BV, unsigned Reg);
+
+ /// Add Reg and its aliases to BV.
+ void addRegWithAliases(BitVector &BV, unsigned Reg);
+
+ unsigned findSurvivorReg(MachineBasicBlock::iterator MI,
+ BitVector &Candidates,
+ unsigned InstrLimit,
+ MachineBasicBlock::iterator &UseMI);
- MachineInstr *findFirstUse(MachineBasicBlock *MBB,
- MachineBasicBlock::iterator I, unsigned Reg,
- unsigned &Dist);
};
-
+
} // End llvm namespace
#endif