skewed_associative.hh

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/*
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 * Authors: Daniel Carvalho
 */

#ifndef __MEM_CACHE_INDEXING_POLICIES_SKEWED_ASSOCIATIVE_HH__
#define __MEM_CACHE_INDEXING_POLICIES_SKEWED_ASSOCIATIVE_HH__

#include <vector>

#include "mem/cache/tags/indexing_policies/base.hh"
#include "params/SkewedAssociative.hh"

class ReplaceableEntry;

class SkewedAssociative : public BaseIndexingPolicy
{
  private:
    const int NUM_SKEWING_FUNCTIONS = 8;

    const int msbShift;

    Addr hash(const Addr addr) const;

    Addr dehash(const Addr addr) const;

    Addr skew(const Addr addr, const uint32_t way) const;

    Addr deskew(const Addr addr, const uint32_t way) const;

    uint32_t extractSet(const Addr addr, const uint32_t way) const;

  public:
     typedef SkewedAssociativeParams Params;

    SkewedAssociative(const Params *p);

    ~SkewedAssociative() {};

    std::vector<ReplaceableEntry*> getPossibleEntries(const Addr addr) const
                                                                   override;

    Addr regenerateAddr(const Addr tag, const ReplaceableEntry* entry) const
                                                                   override;
};

#endif //__MEM_CACHE_INDEXING_POLICIES_SKEWED_ASSOCIATIVE_HH__