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/o3/comm.hh"
#include "cpu/o3/dyn_inst_ptr.hh"
#include "cpu/o3/iew.hh"
#include "cpu/o3/limits.hh"
#include "cpu/o3/rename_map.hh"
#include "cpu/o3/rob.hh"
#include "cpu/timebuf.hh"
#include "enums/CommitPolicy.hh"
#include "sim/probe/probe.hh"
 
namespace gem5
{
 
struct BaseO3CPUParams;
 
namespace o3
{
 
class ThreadState;
 
class Commit
{
  public:
    enum CommitStatus
    {
        Active,
        Inactive
    };
 
    enum ThreadStatus
    {
        Running,
        Idle,
        ROBSquashing,
        TrapPending,
        FetchTrapPending,
        SquashAfterPending, //< Committing instructions before a squash.
    };
 
  private:
    CommitStatus _status;
    CommitStatus _nextStatus;
    ThreadStatus commitStatus[MaxThreads];
    CommitPolicy commitPolicy;
 
    ProbePointArg<DynInstPtr> *ppCommit;
    ProbePointArg<DynInstPtr> *ppCommitStall;
    ProbePointArg<DynInstPtr> *ppSquash;
 
    void processTrapEvent(ThreadID tid);
 
  public:
    Commit(CPU *_cpu, const BaseO3CPUParams &params);
 
    std::string name() const;
 
    void regProbePoints();
 
    void setThreads(std::vector<ThreadState *> &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(UnifiedRenameMap::PerThreadUnifiedRenameMap& rm_ptr);
 
    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:
    const PCStateBase &pcState(ThreadID tid) { return *pc[tid]; }
 
    void pcState(const PCStateBase &val, ThreadID tid) { set(pc[tid], val); }
 
  private:
    TimeBuffer<TimeStruct> *timeBuffer;
 
    TimeBuffer<TimeStruct>::wire toIEW;
 
    TimeBuffer<TimeStruct>::wire robInfoFromIEW;
 
    TimeBuffer<FetchStruct> *fetchQueue;
 
    TimeBuffer<FetchStruct>::wire fromFetch;
 
    TimeBuffer<IEWStruct> *iewQueue;
 
    TimeBuffer<IEWStruct>::wire fromIEW;
 
    TimeBuffer<RenameStruct> *renameQueue;
 
    TimeBuffer<RenameStruct>::wire fromRename;
 
  public:
    ROB *rob;
 
  private:
    CPU *cpu;
 
    std::vector<ThreadState *> thread;
 
    bool wroteToTimeBuffer;
 
    bool changedROBNumEntries[MaxThreads];
 
    bool trapSquash[MaxThreads];
 
    bool tcSquash[MaxThreads];
 
    DynInstPtr squashAfterInst[MaxThreads];
 
    std::list<ThreadID> priority_list;
 
    const Cycles iewToCommitDelay;
 
    const Cycles commitToIEWDelay;
 
    const Cycles renameToROBDelay;
 
    const Cycles fetchToCommitDelay;
 
    const unsigned renameWidth;
 
    const unsigned commitWidth;
 
    const ThreadID numThreads;
 
    bool drainPending;
 
    bool drainImminent;
 
    const Cycles trapLatency;
 
    Fault interrupt;
 
    std::unique_ptr<PCStateBase> pc[MaxThreads];
 
    InstSeqNum youngestSeqNum[MaxThreads];
 
    InstSeqNum lastCommitedSeqNum[MaxThreads];
 
    bool trapInFlight[MaxThreads];
 
    bool committedStores[MaxThreads];
 
    bool checkEmptyROB[MaxThreads];
 
    std::list<ThreadID> *activeThreads;
 
    UnifiedRenameMap *renameMap[MaxThreads];
 
    bool canHandleInterrupts;
 
    bool avoidQuiesceLiveLock;
 
    void updateComInstStats(const DynInstPtr &inst);
 
    // HTM
    int htmStarts[MaxThreads];
    int htmStops[MaxThreads];
 
    struct CommitStats : public statistics::Group
    {
        CommitStats(CPU *cpu, Commit *commit);
        statistics::Scalar commitSquashedInsts;
        statistics::Scalar commitNonSpecStalls;
        statistics::Scalar branchMispredicts;
        statistics::Distribution numCommittedDist;
 
        statistics::Vector amos;
        statistics::Vector membars;
        statistics::Vector functionCalls;
        statistics::Vector2d committedInstType;
 
        statistics::Scalar commitEligibleSamples;
    } stats;
};
 
} // namespace o3
} // namespace gem5
 
#endif // __CPU_O3_COMMIT_HH__