src/mem/cache/compressors/cpack.cc

/*
 * Copyright (c) 2018-2020 Inria
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/** @file
 * Implementation of the CPack cache compressor.
 */

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

#include "mem/cache/compressors/dictionary_compressor_impl.hh"
#include "params/CPack.hh"

namespace Compressor {

CPack::CPack(const Params *p)
    : DictionaryCompressor<uint32_t>(p)
{
}

void
CPack::addToDictionary(DictionaryEntry data)
{
    assert(numEntries < dictionarySize);
    dictionary[numEntries++] = data;
}

std::unique_ptr<Base::CompressionData>
CPack::compress(const std::vector<Chunk>& chunks,
    Cycles& comp_lat, Cycles& decomp_lat)
{
    std::unique_ptr<Base::CompressionData> comp_data =
        DictionaryCompressor<uint32_t>::compress(chunks);

    // Set compression latency (Accounts for pattern matching, length
    // generation, packaging and shifting)
    comp_lat = Cycles(blkSize/8+5);

    // Set decompression latency (1 qword per cycle)
    decomp_lat = Cycles(blkSize/8);

    // Return compressed line
    return comp_data;
}

} // namespace Compressor

Compressor::CPack*
CPackParams::create()
{
    return new Compressor::CPack(this);
}