/*
 * Copyright (c) 2019-2020 Inria
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 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * redistributions in binary form must reproduce the above copyright
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 * neither the name of the copyright holders nor the names of its
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 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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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
{

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