src/mem/cache/compressors/fpcd.cc

/*
 * Copyright (c) 2019-2020 Inria
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/** @file
 * Implementation of the FPC-D cache compressor.
 */

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

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

namespace gem5
{

GEM5_DEPRECATED_NAMESPACE(Compressor, compression);
namespace compression
{

FPCD::FPCD(const Params &p)
    : DictionaryCompressor<uint32_t>(p)
{
}

void
FPCD::addToDictionary(DictionaryEntry data)
{
    // The dictionary behaves as a table with FIFO as replacement policy
    if (numEntries == 2) {
        dictionary[penultimateIndex] = dictionary[previousIndex];
        dictionary[previousIndex] = data;
    } else {
        dictionary[numEntries++] = data;
    }
}

} // namespace compression
} // namespace gem5