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"
#include "mem/ruby/system/RubySystem.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;
    }
 
    void setRubySystem(RubySystem* rs);
 
    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 = 0;
    int m_block_size = 0;
    RubySystem* m_ruby_system = nullptr;
 
    static constexpr bool entryRequiresRubySystem =
        std::is_member_function_pointer_v<decltype(&ENTRY::setRubySystem)>;
};
 
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
void TBETable<ENTRY>::setRubySystem(RubySystem* rs)
{
    m_ruby_system = rs;
    m_block_size = rs->getBlockSizeBytes();
}
 
template<class ENTRY>
inline bool
TBETable<ENTRY>::isPresent(Addr address) const
{
    assert(address == makeLineAddress(address, floorLog2(m_block_size)));
    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);
    assert(m_block_size > 0);
    ENTRY new_entry = ENTRY(m_block_size);
    new_entry.setRubySystem(m_ruby_system);
    m_map.emplace(address, new_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__