2bit_local.hh

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#ifndef __CPU_PRED_2BIT_LOCAL_PRED_HH__
#define __CPU_PRED_2BIT_LOCAL_PRED_HH__
 
#include <vector>
 
#include "base/sat_counter.hh"
#include "base/types.hh"
#include "cpu/pred/bpred_unit.hh"
#include "params/LocalBP.hh"
 
namespace gem5
{
 
namespace branch_prediction
{
 
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, const StaticInstPtr & inst, Addr corrTarget);
 
    void squash(ThreadID tid, void *bp_history)
    { assert(bp_history == NULL); }
 
  private:
    inline bool getPrediction(uint8_t &count);
 
    inline unsigned getLocalIndex(Addr &PC);
 
    const unsigned localPredictorSize;
 
    const unsigned localCtrBits;
 
    const unsigned localPredictorSets;
 
    std::vector<SatCounter8> localCtrs;
 
    const unsigned indexMask;
};
 
} // namespace branch_prediction
} // namespace gem5
 
#endif // __CPU_PRED_2BIT_LOCAL_PRED_HH__