rob.hh

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/*
 * Copyright (c) 2012 ARM Limited
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 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
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 * modified or unmodified, in source code or in binary form.
 *
 * Copyright (c) 2004-2006 The Regents of The University of Michigan
 * All rights reserved.
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 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
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#ifndef __CPU_O3_ROB_HH__
#define __CPU_O3_ROB_HH__
 
#include <string>
#include <utility>
#include <vector>
 
#include "arch/registers.hh"
#include "base/types.hh"
#include "config/the_isa.hh"
#include "enums/SMTQueuePolicy.hh"
 
struct DerivO3CPUParams;
 
template <class Impl>
class ROB
{
  public:
    //Typedefs from the Impl.
    typedef typename Impl::O3CPU O3CPU;
    typedef typename Impl::DynInstPtr DynInstPtr;
 
    typedef std::pair<RegIndex, PhysRegIndex> UnmapInfo;
    typedef typename std::list<DynInstPtr>::iterator InstIt;
 
    enum Status {
        Running,
        Idle,
        ROBSquashing
    };
 
  private:
    Status robStatus[Impl::MaxThreads];
 
    SMTQueuePolicy robPolicy;
 
  public:
    ROB(O3CPU *_cpu, DerivO3CPUParams *params);
 
    std::string name() const;
 
    void setActiveThreads(std::list<ThreadID> *at_ptr);
 
    void drainSanityCheck() const;
 
    void takeOverFrom();
 
    void insertInst(const DynInstPtr &inst);
 
//    DynInstPtr readHeadInst();
 
    const DynInstPtr &readHeadInst(ThreadID tid);
 
    DynInstPtr findInst(ThreadID tid, InstSeqNum squash_inst);
 
//    DynInstPtr readTailInst();
 
    DynInstPtr readTailInst(ThreadID tid);
 
//    void retireHead();
 
    void retireHead(ThreadID tid);
 
//    bool isHeadReady();
 
    bool isHeadReady(ThreadID tid);
 
    bool canCommit();
 
    void resetEntries();
 
    int entryAmount(ThreadID num_threads);
 
    unsigned numFreeEntries();
 
    unsigned numFreeEntries(ThreadID tid);
 
    unsigned getMaxEntries(ThreadID tid)
    { return maxEntries[tid]; }
 
    unsigned getThreadEntries(ThreadID tid)
    { return threadEntries[tid]; }
 
    bool isFull()
    { return numInstsInROB == numEntries; }
 
    bool isFull(ThreadID tid)
    { return threadEntries[tid] == numEntries; }
 
    bool isEmpty() const
    { return numInstsInROB == 0; }
 
    bool isEmpty(ThreadID tid) const
    { return threadEntries[tid] == 0; }
 
    void doSquash(ThreadID tid);
 
    void squash(InstSeqNum squash_num, ThreadID tid);
 
    void updateHead();
 
    void updateTail();
 
//    uint64_t readHeadPC();
 
//    uint64_t readHeadPC(ThreadID tid);
 
//    uint64_t readHeadNextPC();
 
//    uint64_t readHeadNextPC(ThreadID tid);
 
//    InstSeqNum readHeadSeqNum();
 
//    InstSeqNum readHeadSeqNum(ThreadID tid);
 
//    uint64_t readTailPC();
 
//    uint64_t readTailPC(ThreadID tid);
 
//    InstSeqNum readTailSeqNum();
 
//    InstSeqNum readTailSeqNum(ThreadID tid);
 
    bool isDoneSquashing(ThreadID tid) const
    { return doneSquashing[tid]; }
 
    bool isDoneSquashing();
 
    int countInsts();
 
    size_t countInsts(ThreadID tid);
 
  private:
    void resetState();
 
    O3CPU *cpu;
 
    std::list<ThreadID> *activeThreads;
 
    unsigned numEntries;
 
    unsigned threadEntries[Impl::MaxThreads];
 
    unsigned maxEntries[Impl::MaxThreads];
 
    std::list<DynInstPtr> instList[Impl::MaxThreads];
 
    unsigned squashWidth;
 
  public:
    InstIt tail;
 
    InstIt head;
 
  private:
    InstIt squashIt[Impl::MaxThreads];
 
  public:
    int numInstsInROB;
 
    DynInstPtr dummyInst;
 
  private:
    InstSeqNum squashedSeqNum[Impl::MaxThreads];
 
    bool doneSquashing[Impl::MaxThreads];
 
    ThreadID numThreads;
 
 
    struct ROBStats : public Stats::Group {
        ROBStats(Stats::Group *parent);
 
        // The number of rob_reads
        Stats::Scalar reads;
        // The number of rob_writes
        Stats::Scalar writes;
    } stats;
};
 
#endif //__CPU_O3_ROB_HH__