zero.hh

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/*
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#ifndef __MEM_CACHE_COMPRESSORS_ZERO_HH__
#define __MEM_CACHE_COMPRESSORS_ZERO_HH__

#include <array>
#include <cstdint>
#include <map>
#include <memory>

#include "mem/cache/compressors/dictionary_compressor.hh"

struct ZeroCompressorParams;

class ZeroCompressor : public DictionaryCompressor<uint64_t>
{
  protected:
    using DictionaryEntry = DictionaryCompressor<uint64_t>::DictionaryEntry;

    // Forward declaration of all possible patterns
    class PatternX;
    class PatternZ;

    typedef enum {
        X, Z, NUM_PATTERNS
    } PatternNumber;

    using PatternFactory = Factory<PatternZ, PatternX>;

    uint64_t getNumPatterns() const override { return NUM_PATTERNS; }

    std::string
    getName(int number) const override
    {
        static std::map<int, std::string> pattern_names = {
            {X, "X"}, {Z, "Z"}
        };

        return pattern_names[number];
    };

    std::unique_ptr<Pattern>
    getPattern(const DictionaryEntry& bytes, const DictionaryEntry& dict_bytes,
        const int match_location) const override
    {
        return PatternFactory::getPattern(bytes, dict_bytes, match_location);
    }

    void addToDictionary(DictionaryEntry data) override;

    std::unique_ptr<BaseCacheCompressor::CompressionData> compress(
        const uint64_t* data, Cycles& comp_lat, Cycles& decomp_lat) override;

  public:
    typedef ZeroCompressorParams Params;
    ZeroCompressor(const Params *p);
    ~ZeroCompressor() = default;
};

class ZeroCompressor::PatternX
    : public DictionaryCompressor::UncompressedPattern
{
  public:
    PatternX(const DictionaryEntry bytes, const int match_location)
        : DictionaryCompressor::UncompressedPattern(X, 0, 1, match_location,
          bytes)
    {
    }
};

class ZeroCompressor::PatternZ
    : public DictionaryCompressor::MaskedValuePattern<0, 0xFFFFFFFFFFFFFFFF>
{
  public:
    PatternZ(const DictionaryEntry bytes, const int match_location)
        : DictionaryCompressor::MaskedValuePattern<0, 0xFFFFFFFFFFFFFFFF>(
          Z, 1, 1, match_location, bytes)
    {
    }
};

#endif //__MEM_CACHE_COMPRESSORS_ZERO_HH__