commit.hh

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#ifndef __CPU_O3_COMMIT_HH__
#define __CPU_O3_COMMIT_HH__
 
#include <queue>
 
#include "base/statistics.hh"
#include "cpu/exetrace.hh"
#include "cpu/inst_seq.hh"
#include "cpu/timebuf.hh"
#include "enums/CommitPolicy.hh"
#include "sim/probe/probe.hh"
 
struct DerivO3CPUParams;
 
template <class>
struct O3ThreadState;
 
template<class Impl>
class DefaultCommit
{
  public:
    // Typedefs from the Impl.
    typedef typename Impl::O3CPU O3CPU;
    typedef typename Impl::DynInstPtr DynInstPtr;
    typedef typename Impl::CPUPol CPUPol;
 
    typedef typename CPUPol::RenameMap RenameMap;
    typedef typename CPUPol::ROB ROB;
 
    typedef typename CPUPol::TimeStruct TimeStruct;
    typedef typename CPUPol::FetchStruct FetchStruct;
    typedef typename CPUPol::IEWStruct IEWStruct;
    typedef typename CPUPol::RenameStruct RenameStruct;
 
    typedef typename CPUPol::Fetch Fetch;
    typedef typename CPUPol::IEW IEW;
 
    typedef O3ThreadState<Impl> Thread;
 
    enum CommitStatus{
        Active,
        Inactive
    };
 
    enum ThreadStatus {
        Running,
        Idle,
        ROBSquashing,
        TrapPending,
        FetchTrapPending,
        SquashAfterPending, //< Committing instructions before a squash.
    };
 
  private:
    CommitStatus _status;
    CommitStatus _nextStatus;
    ThreadStatus commitStatus[Impl::MaxThreads];
    CommitPolicy commitPolicy;
 
    ProbePointArg<DynInstPtr> *ppCommit;
    ProbePointArg<DynInstPtr> *ppCommitStall;
    ProbePointArg<DynInstPtr> *ppSquash;
 
    void processTrapEvent(ThreadID tid);
 
  public:
    DefaultCommit(O3CPU *_cpu, DerivO3CPUParams *params);
 
    std::string name() const;
 
    void regProbePoints();
 
    void setThreads(std::vector<Thread *> &threads);
 
    void setTimeBuffer(TimeBuffer<TimeStruct> *tb_ptr);
 
    void setFetchQueue(TimeBuffer<FetchStruct> *fq_ptr);
 
    void setRenameQueue(TimeBuffer<RenameStruct> *rq_ptr);
 
    void setIEWQueue(TimeBuffer<IEWStruct> *iq_ptr);
 
    void setIEWStage(IEW *iew_stage);
 
    IEW *iewStage;
 
    void setActiveThreads(std::list<ThreadID> *at_ptr);
 
    void setRenameMap(RenameMap rm_ptr[Impl::MaxThreads]);
 
    void setROB(ROB *rob_ptr);
 
    void startupStage();
 
    void clearStates(ThreadID tid);
 
    void drain();
 
    void drainResume();
 
    void drainSanityCheck() const;
 
    bool isDrained() const;
 
    void takeOverFrom();
 
    void deactivateThread(ThreadID tid);
 
    bool executingHtmTransaction(ThreadID) const;
 
    /* Reset HTM tracking, e.g. after an abort */
    void resetHtmStartsStops(ThreadID);
 
    void tick();
 
    void commit();
 
    size_t numROBFreeEntries(ThreadID tid);
 
    void generateTrapEvent(ThreadID tid, Fault inst_fault);
 
    void generateTCEvent(ThreadID tid);
 
  private:
    void updateStatus();
 
    bool changedROBEntries();
 
    void squashAll(ThreadID tid);
 
    void squashFromTrap(ThreadID tid);
 
    void squashFromTC(ThreadID tid);
 
    void squashFromSquashAfter(ThreadID tid);
 
    void squashAfter(ThreadID tid, const DynInstPtr &head_inst);
 
    void handleInterrupt();
 
    void propagateInterrupt();
 
    void commitInsts();
 
    bool commitHead(const DynInstPtr &head_inst, unsigned inst_num);
 
    void getInsts();
 
    void markCompletedInsts();
 
    ThreadID getCommittingThread();
 
    ThreadID roundRobin();
 
    ThreadID oldestReady();
 
  public:
    TheISA::PCState pcState(ThreadID tid) { return pc[tid]; }
 
    void pcState(const TheISA::PCState &val, ThreadID tid)
    { pc[tid] = val; }
 
    Addr instAddr(ThreadID tid) { return pc[tid].instAddr(); }
 
    Addr nextInstAddr(ThreadID tid) { return pc[tid].nextInstAddr(); }
 
    Addr microPC(ThreadID tid) { return pc[tid].microPC(); }
 
  private:
    TimeBuffer<TimeStruct> *timeBuffer;
 
    typename TimeBuffer<TimeStruct>::wire toIEW;
 
    typename TimeBuffer<TimeStruct>::wire robInfoFromIEW;
 
    TimeBuffer<FetchStruct> *fetchQueue;
 
    typename TimeBuffer<FetchStruct>::wire fromFetch;
 
    TimeBuffer<IEWStruct> *iewQueue;
 
    typename TimeBuffer<IEWStruct>::wire fromIEW;
 
    TimeBuffer<RenameStruct> *renameQueue;
 
    typename TimeBuffer<RenameStruct>::wire fromRename;
 
  public:
    ROB *rob;
 
  private:
    O3CPU *cpu;
 
    std::vector<Thread *> thread;
 
    bool wroteToTimeBuffer;
 
    bool changedROBNumEntries[Impl::MaxThreads];
 
    bool trapSquash[Impl::MaxThreads];
 
    bool tcSquash[Impl::MaxThreads];
 
    DynInstPtr squashAfterInst[Impl::MaxThreads];
 
    std::list<ThreadID> priority_list;
 
    const Cycles iewToCommitDelay;
 
    const Cycles commitToIEWDelay;
 
    const Cycles renameToROBDelay;
 
    const Cycles fetchToCommitDelay;
 
    const unsigned renameWidth;
 
    const unsigned commitWidth;
 
    unsigned numRobs;
 
    const ThreadID numThreads;
 
    bool drainPending;
 
    bool drainImminent;
 
    const Cycles trapLatency;
 
    Fault interrupt;
 
    TheISA::PCState pc[Impl::MaxThreads];
 
    InstSeqNum youngestSeqNum[Impl::MaxThreads];
 
    InstSeqNum lastCommitedSeqNum[Impl::MaxThreads];
 
    bool trapInFlight[Impl::MaxThreads];
 
    bool committedStores[Impl::MaxThreads];
 
    bool checkEmptyROB[Impl::MaxThreads];
 
    std::list<ThreadID> *activeThreads;
 
    RenameMap *renameMap[Impl::MaxThreads];
 
    bool canHandleInterrupts;
 
    bool avoidQuiesceLiveLock;
 
    void updateComInstStats(const DynInstPtr &inst);
 
    // HTM
    int htmStarts[Impl::MaxThreads];
    int htmStops[Impl::MaxThreads];
 
    struct CommitStats : public Stats::Group {
        CommitStats(O3CPU *cpu, DefaultCommit *commit);
        Stats::Scalar commitSquashedInsts;
        Stats::Scalar commitNonSpecStalls;
        Stats::Scalar branchMispredicts;
        Stats::Distribution numCommittedDist;
 
        Stats::Vector instsCommitted;
        Stats::Vector opsCommitted;
        Stats::Vector memRefs;
        Stats::Vector loads;
        Stats::Vector amos;
        Stats::Vector membars;
        Stats::Vector branches;
        Stats::Vector vector;
        Stats::Vector floating;
        Stats::Vector integer;
        Stats::Vector functionCalls;
        Stats::Vector2d committedInstType;
 
        Stats::Scalar commitEligibleSamples;
    } stats;
};
 
#endif // __CPU_O3_COMMIT_HH__