2bit_local.hh

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/*
 * Copyright (c) 2011, 2014 ARM Limited
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 * Copyright (c) 2004-2006 The Regents of The University of Michigan
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 * met: redistributions of source code must retain the above copyright
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 * Authors: Kevin Lim
 *          Timothy M. Jones
 */

#ifndef __CPU_PRED_2BIT_LOCAL_PRED_HH__
#define __CPU_PRED_2BIT_LOCAL_PRED_HH__

#include <vector>

#include "base/types.hh"
#include "cpu/pred/bpred_unit.hh"
#include "cpu/pred/sat_counter.hh"
#include "params/LocalBP.hh"

class LocalBP : public BPredUnit
{
  public:
    LocalBP(const LocalBPParams *params);

    virtual void uncondBranch(ThreadID tid, Addr pc, void * &bp_history);

    bool lookup(ThreadID tid, Addr branch_addr, void * &bp_history);

    void btbUpdate(ThreadID tid, Addr branch_addr, void * &bp_history);

    void update(ThreadID tid, Addr branch_addr, bool taken, void *bp_history,
                bool squashed);

    void squash(ThreadID tid, void *bp_history)
    { assert(bp_history == NULL); }

    void reset();

  private:
    inline bool getPrediction(uint8_t &count);

    inline unsigned getLocalIndex(Addr &PC);

    std::vector<SatCounter> localCtrs;

    unsigned localPredictorSize;

    unsigned localPredictorSets;

    unsigned localCtrBits;

    unsigned indexMask;
};

#endif // __CPU_PRED_2BIT_LOCAL_PRED_HH__