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#ifndef QV4REGALLOC_P_H
#define QV4REGALLOC_P_H

#include "qv4global_p.h"
#include "qv4isel_p.h"
#include "qv4ssa_p.h"

#include <config.h>

QT_BEGIN_NAMESPACE

namespace QQmlJS {
namespace MASM {

class RegAllocInfo;

class RegisterAllocator
{
    typedef V4IR::LifeTimeInterval LifeTimeInterval;

    const QVector<int> &_normalRegisters;
    const QVector<int> &_fpRegisters;
    QScopedPointer<RegAllocInfo> _info;

    QVector<LifeTimeInterval> _fixedRegisterRanges, _fixedFPRegisterRanges;

    QVector<LifeTimeInterval> _unhandled, _active, _inactive, _handled;

    QHash<V4IR::Temp, int> _lastAssignedRegister;
    QHash<V4IR::Temp, int> _assignedSpillSlots;
    QVector<int> _activeSpillSlots;

    Q_DISABLE_COPY(RegisterAllocator)

public:
    RegisterAllocator(const QVector<int> &normalRegisters, const QVector<int> &fpRegisters);
    ~RegisterAllocator();

    void run(V4IR::Function *function, const V4IR::Optimizer &opt);

private:
    void prepareRanges();
    void linearScan();
    void tryAllocateFreeReg(LifeTimeInterval &current, const int position);
    void allocateBlockedReg(LifeTimeInterval &current, const int position);
    void longestAvailableReg(const QVector<int> &nextUses, int &reg, int &nextUsePos_reg,
                             int lastUse) const;
    int nextIntersection(const LifeTimeInterval &current, const LifeTimeInterval &another,
                         const int position) const;
    int nextUse(const V4IR::Temp &t, int startPosition) const;
    void split(LifeTimeInterval &current, int beforePosition, bool skipOptionalRegisterUses =false);
    void splitInactiveAtEndOfLifetimeHole(int reg, bool isFPReg, int position);
    void assignSpillSlot(const V4IR::Temp &t, int startPos, int endPos);
    void resolve(V4IR::Function *function, const V4IR::Optimizer &opt);

    void dump() const;
};

} // end of namespace MASM
} // end of namespace QQmlJS

QT_END_NAMESPACE

#endif // QV4REGALLOC_P_H
