iew.hh

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/*
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 * All rights reserved.
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 * Authors: Kevin Lim
 */

#ifndef __CPU_O3_IEW_HH__
#define __CPU_O3_IEW_HH__

#include <queue>
#include <set>

#include "base/statistics.hh"
#include "cpu/o3/comm.hh"
#include "cpu/o3/lsq.hh"
#include "cpu/o3/scoreboard.hh"
#include "cpu/timebuf.hh"
#include "debug/IEW.hh"
#include "sim/probe/probe.hh"

struct DerivO3CPUParams;
class FUPool;

template<class Impl>
class DefaultIEW
{
  private:
    //Typedefs from Impl
    typedef typename Impl::CPUPol CPUPol;
    typedef typename Impl::DynInstPtr DynInstPtr;
    typedef typename Impl::O3CPU O3CPU;

    typedef typename CPUPol::IQ IQ;
    typedef typename CPUPol::RenameMap RenameMap;
    typedef typename CPUPol::LSQ LSQ;

    typedef typename CPUPol::TimeStruct TimeStruct;
    typedef typename CPUPol::IEWStruct IEWStruct;
    typedef typename CPUPol::RenameStruct RenameStruct;
    typedef typename CPUPol::IssueStruct IssueStruct;

  public:
    enum Status {
        Active,
        Inactive
    };

    enum StageStatus {
        Running,
        Blocked,
        Idle,
        StartSquash,
        Squashing,
        Unblocking
    };

  private:
    Status _status;
    StageStatus dispatchStatus[Impl::MaxThreads];
    StageStatus exeStatus;
    StageStatus wbStatus;

    ProbePointArg<DynInstPtr> *ppMispredict;
    ProbePointArg<DynInstPtr> *ppDispatch;
    ProbePointArg<DynInstPtr> *ppExecute;
    ProbePointArg<DynInstPtr> *ppToCommit;

  public:
    DefaultIEW(O3CPU *_cpu, DerivO3CPUParams *params);

    std::string name() const;

    void regStats();

    void regProbePoints();

    void startupStage();

    void clearStates(ThreadID tid);

    void setTimeBuffer(TimeBuffer<TimeStruct> *tb_ptr);

    void setRenameQueue(TimeBuffer<RenameStruct> *rq_ptr);

    void setIEWQueue(TimeBuffer<IEWStruct> *iq_ptr);

    void setActiveThreads(std::list<ThreadID> *at_ptr);

    void setScoreboard(Scoreboard *sb_ptr);

    void drainSanityCheck() const;

    bool isDrained() const;

    void takeOverFrom();

    void squash(ThreadID tid);

    void wakeDependents(const DynInstPtr &inst);

    void rescheduleMemInst(const DynInstPtr &inst);

    void replayMemInst(const DynInstPtr &inst);

    void blockMemInst(const DynInstPtr &inst);

    void cacheUnblocked();

    void instToCommit(const DynInstPtr &inst);

    void skidInsert(ThreadID tid);

    int skidCount();

    bool skidsEmpty();

    void updateStatus();

    void resetEntries();

    void wakeCPU();

    void activityThisCycle();

    inline void activateStage();

    inline void deactivateStage();

    bool hasStoresToWB() { return ldstQueue.hasStoresToWB(); }

    bool hasStoresToWB(ThreadID tid) { return ldstQueue.hasStoresToWB(tid); }

    void checkMisprediction(const DynInstPtr &inst);

  private:
    void squashDueToBranch(const DynInstPtr &inst, ThreadID tid);

    void squashDueToMemOrder(const DynInstPtr &inst, ThreadID tid);

    void block(ThreadID tid);

    void unblock(ThreadID tid);

    void dispatch(ThreadID tid);

    void dispatchInsts(ThreadID tid);

    void executeInsts();

    void writebackInsts();

    unsigned validInstsFromRename();

    bool checkStall(ThreadID tid);

    void checkSignalsAndUpdate(ThreadID tid);

    void emptyRenameInsts(ThreadID tid);

    void sortInsts();

  public:
    void tick();

  private:
    void updateExeInstStats(const DynInstPtr &inst);

    TimeBuffer<TimeStruct> *timeBuffer;

    typename TimeBuffer<TimeStruct>::wire toFetch;

    typename TimeBuffer<TimeStruct>::wire fromCommit;

    typename TimeBuffer<TimeStruct>::wire toRename;

    TimeBuffer<RenameStruct> *renameQueue;

    typename TimeBuffer<RenameStruct>::wire fromRename;

    TimeBuffer<IssueStruct> issueToExecQueue;

    typename TimeBuffer<IssueStruct>::wire fromIssue;

    TimeBuffer<IEWStruct> *iewQueue;

    typename TimeBuffer<IEWStruct>::wire toCommit;

    std::queue<DynInstPtr> insts[Impl::MaxThreads];

    std::queue<DynInstPtr> skidBuffer[Impl::MaxThreads];

    Scoreboard* scoreboard;

  private:
    O3CPU *cpu;

    bool wroteToTimeBuffer;

    void printAvailableInsts();

  public:
    IQ instQueue;

    LSQ ldstQueue;

    FUPool *fuPool;
    bool updateLSQNextCycle;

  private:
    bool fetchRedirect[Impl::MaxThreads];

    bool updatedQueues;

    Cycles commitToIEWDelay;

    Cycles renameToIEWDelay;

    Cycles issueToExecuteDelay;

    unsigned dispatchWidth;

    unsigned issueWidth;

    unsigned wbNumInst;

    unsigned wbCycle;

    unsigned wbWidth;

    ThreadID numThreads;

    std::list<ThreadID> *activeThreads;

    unsigned skidBufferMax;

    Stats::Scalar iewIdleCycles;
    Stats::Scalar iewSquashCycles;
    Stats::Scalar iewBlockCycles;
    Stats::Scalar iewUnblockCycles;
    Stats::Scalar iewDispatchedInsts;
    Stats::Scalar iewDispSquashedInsts;
    Stats::Scalar iewDispLoadInsts;
    Stats::Scalar iewDispStoreInsts;
    Stats::Scalar iewDispNonSpecInsts;
    Stats::Scalar iewIQFullEvents;
    Stats::Scalar iewLSQFullEvents;
    Stats::Scalar memOrderViolationEvents;
    Stats::Scalar predictedTakenIncorrect;
    Stats::Scalar predictedNotTakenIncorrect;
    Stats::Formula branchMispredicts;

    Stats::Scalar iewExecutedInsts;
    Stats::Vector iewExecLoadInsts;
//    Stats::Scalar iewExecStoreInsts;
    Stats::Scalar iewExecSquashedInsts;
    Stats::Vector iewExecutedSwp;
    Stats::Vector iewExecutedNop;
    Stats::Vector iewExecutedRefs;
    Stats::Vector iewExecutedBranches;
    Stats::Formula iewExecStoreInsts;
    Stats::Formula iewExecRate;

    Stats::Vector iewInstsToCommit;
    Stats::Vector writebackCount;
    Stats::Vector producerInst;
    Stats::Vector consumerInst;
    Stats::Formula wbRate;
    Stats::Formula wbFanout;
};

#endif // __CPU_O3_IEW_HH__