bop.hh

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#ifndef __MEM_CACHE_PREFETCH_BOP_HH__
#define __MEM_CACHE_PREFETCH_BOP_HH__

#include <queue>

#include "mem/cache/prefetch/queued.hh"
#include "mem/packet.hh"

struct BOPPrefetcherParams;

namespace Prefetcher {

class BOP : public Queued
{
    private:

        enum RRWay {
            Left,
            Right
        };

        const unsigned int scoreMax;
        const unsigned int roundMax;
        const unsigned int badScore;
        const unsigned int rrEntries;
        const unsigned int tagMask;
        const bool         delayQueueEnabled;
        const unsigned int delayQueueSize;
        const unsigned int delayTicks;

        std::vector<Addr> rrLeft;
        std::vector<Addr> rrRight;

        typedef std::pair<int16_t, uint8_t> OffsetListEntry;
        std::vector<OffsetListEntry> offsetsList;

        struct DelayQueueEntry
        {
            Addr baseAddr;
            Tick processTick;

            DelayQueueEntry(Addr x, Tick t) : baseAddr(x), processTick(t)
            {}
        };

        std::deque<DelayQueueEntry> delayQueue;

        void delayQueueEventWrapper();
        EventFunctionWrapper delayQueueEvent;

        bool issuePrefetchRequests;
        Addr bestOffset;
        Addr phaseBestOffset;
        std::vector<OffsetListEntry>::iterator offsetsListIterator;
        unsigned int bestScore;
        unsigned int round;

        unsigned int hash(Addr addr, unsigned int way) const;

        void insertIntoRR(Addr addr, unsigned int way);

        void insertIntoDelayQueue(Addr addr);

        void resetScores();

        Addr tag(Addr addr) const;

        bool testRR(Addr) const;

        void bestOffsetLearning(Addr);

        void notifyFill(const PacketPtr& pkt) override;

    public:

        BOP(const BOPPrefetcherParams *p);
        ~BOP() = default;

        void calculatePrefetch(const PrefetchInfo &pfi,
                               std::vector<AddrPriority> &addresses) override;
};

} // namespace Prefetcher

#endif /* __MEM_CACHE_PREFETCH_BOP_HH__ */