gem5/src/mem/ruby/structures/TBETable.hh

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#ifndef __MEM_RUBY_STRUCTURES_TBETABLE_HH__
#define __MEM_RUBY_STRUCTURES_TBETABLE_HH__

#include <iostream>
#include <unordered_map>

#include "mem/ruby/common/Address.hh"

namespace gem5
{

namespace ruby
{

template<class ENTRY>
class TBETable
{
  public:
    TBETable(int number_of_TBEs)
        : m_number_of_TBEs(number_of_TBEs)
    {
    }

    bool isPresent(Addr address) const;
    void allocate(Addr address);
    void deallocate(Addr address);
    bool
    areNSlotsAvailable(int n, Tick current_time) const
    {
        return (m_number_of_TBEs - m_map.size()) >= n;
    }

    ENTRY *getNullEntry();
    ENTRY *lookup(Addr address);

    // Print cache contents
    void print(std::ostream& out) const;

  protected:
    // Protected copy constructor and assignment operator
    TBETable(const TBETable& obj);
    TBETable& operator=(const TBETable& obj);

    // Data Members (m_prefix)
    std::unordered_map<Addr, ENTRY> m_map;

  private:
    int m_number_of_TBEs;
};

template<class ENTRY>
inline std::ostream&
operator<<(std::ostream& out, const TBETable<ENTRY>& obj)
{
    obj.print(out);
    out << std::flush;
    return out;
}

template<class ENTRY>
inline bool
TBETable<ENTRY>::isPresent(Addr address) const
{
    assert(address == makeLineAddress(address));
    assert(m_map.size() <= m_number_of_TBEs);
    return !!m_map.count(address);
}

template<class ENTRY>
inline void
TBETable<ENTRY>::allocate(Addr address)
{
    assert(!isPresent(address));
    assert(m_map.size() < m_number_of_TBEs);
    m_map[address] = ENTRY();
}

template<class ENTRY>
inline void
TBETable<ENTRY>::deallocate(Addr address)
{
    assert(isPresent(address));
    assert(m_map.size() > 0);
    m_map.erase(address);
}

template<class ENTRY>
inline ENTRY*
TBETable<ENTRY>::getNullEntry()
{
    return nullptr;
}

// looks an address up in the cache
template<class ENTRY>
inline ENTRY*
TBETable<ENTRY>::lookup(Addr address)
{
  if (m_map.find(address) != m_map.end()) return &(m_map.find(address)->second);
  return NULL;
}


template<class ENTRY>
inline void
TBETable<ENTRY>::print(std::ostream& out) const
{
}

} // namespace ruby
} // namespace gem5

#endif // __MEM_RUBY_STRUCTURES_TBETABLE_HH__