zero.cc

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/*
 * Copyright (c) 2019 Inria
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 * this software without specific prior written permission.
 *
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 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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#include "mem/cache/compressors/zero.hh"

#include "debug/CacheComp.hh"
#include "mem/cache/compressors/dictionary_compressor_impl.hh"
#include "params/ZeroCompressor.hh"

ZeroCompressor::ZeroCompressor(const Params *p)
    : DictionaryCompressor<uint64_t>(p)
{
}

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

std::unique_ptr<BaseCacheCompressor::CompressionData>
ZeroCompressor::compress(const uint64_t* data, Cycles& comp_lat,
    Cycles& decomp_lat)
{
    std::unique_ptr<BaseCacheCompressor::CompressionData> comp_data =
        DictionaryCompressor::compress(data);

    // If there is any non-zero entry, the compressor failed
    if (numEntries > 0) {
        comp_data->setSizeBits(blkSize * 8);
        DPRINTF(CacheComp, "Zero compression failed\n");
    }

    // Set compression latency (Assumes full line zero comparison)
    comp_lat = Cycles(1);

    // Set decompression latency
    decomp_lat = Cycles(1);

    // Return compressed line
    return comp_data;
}

ZeroCompressor*
ZeroCompressorParams::create()
{
    return new ZeroCompressor(this);
}