113942Sodanrc@yahoo.com.br/*
213942Sodanrc@yahoo.com.br * Copyright (c) 2018 Inria
313942Sodanrc@yahoo.com.br * All rights reserved.
413942Sodanrc@yahoo.com.br *
513942Sodanrc@yahoo.com.br * Redistribution and use in source and binary forms, with or without
613942Sodanrc@yahoo.com.br * modification, are permitted provided that the following conditions are
713942Sodanrc@yahoo.com.br * met: redistributions of source code must retain the above copyright
813942Sodanrc@yahoo.com.br * notice, this list of conditions and the following disclaimer;
913942Sodanrc@yahoo.com.br * redistributions in binary form must reproduce the above copyright
1013942Sodanrc@yahoo.com.br * notice, this list of conditions and the following disclaimer in the
1113942Sodanrc@yahoo.com.br * documentation and/or other materials provided with the distribution;
1213942Sodanrc@yahoo.com.br * neither the name of the copyright holders nor the names of its
1313942Sodanrc@yahoo.com.br * contributors may be used to endorse or promote products derived from
1413942Sodanrc@yahoo.com.br * this software without specific prior written permission.
1513942Sodanrc@yahoo.com.br *
1613942Sodanrc@yahoo.com.br * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1713942Sodanrc@yahoo.com.br * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1813942Sodanrc@yahoo.com.br * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1913942Sodanrc@yahoo.com.br * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
2013942Sodanrc@yahoo.com.br * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
2113942Sodanrc@yahoo.com.br * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
2213942Sodanrc@yahoo.com.br * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
2313942Sodanrc@yahoo.com.br * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
2413942Sodanrc@yahoo.com.br * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
2513942Sodanrc@yahoo.com.br * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
2613942Sodanrc@yahoo.com.br * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
2713942Sodanrc@yahoo.com.br *
2813942Sodanrc@yahoo.com.br * Authors: Daniel Carvalho
2913942Sodanrc@yahoo.com.br */
3013942Sodanrc@yahoo.com.br
3113942Sodanrc@yahoo.com.br/** @file
3213942Sodanrc@yahoo.com.br * Definition of a basic cache compressor.
3313942Sodanrc@yahoo.com.br * A cache compressor must consist of a compression and a decompression
3413942Sodanrc@yahoo.com.br * methods. It must also be aware of the size of an uncompressed cache
3513942Sodanrc@yahoo.com.br * line.
3613942Sodanrc@yahoo.com.br */
3713942Sodanrc@yahoo.com.br
3813942Sodanrc@yahoo.com.br#ifndef __MEM_CACHE_COMPRESSORS_BASE_HH__
3913942Sodanrc@yahoo.com.br#define __MEM_CACHE_COMPRESSORS_BASE_HH__
4013942Sodanrc@yahoo.com.br
4113942Sodanrc@yahoo.com.br#include <cstdint>
4213942Sodanrc@yahoo.com.br
4313943Sodanrc@yahoo.com.br#include "base/statistics.hh"
4413942Sodanrc@yahoo.com.br#include "base/types.hh"
4513942Sodanrc@yahoo.com.br#include "sim/sim_object.hh"
4613942Sodanrc@yahoo.com.br
4713942Sodanrc@yahoo.com.brclass CacheBlk;
4813942Sodanrc@yahoo.com.brstruct BaseCacheCompressorParams;
4913942Sodanrc@yahoo.com.br
5013942Sodanrc@yahoo.com.br/**
5113942Sodanrc@yahoo.com.br * Base cache compressor interface. Every cache compressor must implement a
5213942Sodanrc@yahoo.com.br * compression and a decompression method.
5313942Sodanrc@yahoo.com.br */
5413942Sodanrc@yahoo.com.brclass BaseCacheCompressor : public SimObject {
5513942Sodanrc@yahoo.com.br  protected:
5613942Sodanrc@yahoo.com.br    /**
5713942Sodanrc@yahoo.com.br     * Forward declaration of compression data. Every new compressor must
5813942Sodanrc@yahoo.com.br     * create a new compression data based on it.
5913942Sodanrc@yahoo.com.br     */
6013942Sodanrc@yahoo.com.br    class CompressionData;
6113942Sodanrc@yahoo.com.br
6213942Sodanrc@yahoo.com.br    /**
6313942Sodanrc@yahoo.com.br     * Uncompressed cache line size (in bytes).
6413942Sodanrc@yahoo.com.br     */
6513942Sodanrc@yahoo.com.br    const std::size_t blkSize;
6613942Sodanrc@yahoo.com.br
6713942Sodanrc@yahoo.com.br    /**
6813943Sodanrc@yahoo.com.br     * @defgroup CompressionStats Compression specific statistics.
6913943Sodanrc@yahoo.com.br     * @{
7013943Sodanrc@yahoo.com.br     */
7113943Sodanrc@yahoo.com.br
7213943Sodanrc@yahoo.com.br    /** Number of blocks that were compressed to this power of two size. */
7313943Sodanrc@yahoo.com.br    Stats::Vector compressionSize;
7413943Sodanrc@yahoo.com.br
7513943Sodanrc@yahoo.com.br    /**
7613943Sodanrc@yahoo.com.br     * @}
7713943Sodanrc@yahoo.com.br     */
7813943Sodanrc@yahoo.com.br
7913943Sodanrc@yahoo.com.br    /**
8013942Sodanrc@yahoo.com.br     * Apply the compression process to the cache line.
8113942Sodanrc@yahoo.com.br     * Returns the number of cycles used by the compressor, however it is
8213942Sodanrc@yahoo.com.br     * usually covered by a good pipelined execution, and is currently ignored.
8313942Sodanrc@yahoo.com.br     * The decompression latency is also returned, in order to avoid
8413942Sodanrc@yahoo.com.br     * increasing simulation time and memory consumption.
8513942Sodanrc@yahoo.com.br     *
8613942Sodanrc@yahoo.com.br     * @param cache_line The cache line to be compressed.
8713942Sodanrc@yahoo.com.br     * @param comp_lat Compression latency in number of cycles.
8813942Sodanrc@yahoo.com.br     * @param decomp_lat Decompression latency in number of cycles.
8913942Sodanrc@yahoo.com.br     * @return Cache line after compression.
9013942Sodanrc@yahoo.com.br     */
9113942Sodanrc@yahoo.com.br    virtual std::unique_ptr<CompressionData> compress(
9213942Sodanrc@yahoo.com.br        const uint64_t* cache_line, Cycles& comp_lat, Cycles& decomp_lat) = 0;
9313942Sodanrc@yahoo.com.br
9413942Sodanrc@yahoo.com.br    /**
9513942Sodanrc@yahoo.com.br     * Apply the decompression process to the compressed data.
9613942Sodanrc@yahoo.com.br     *
9713942Sodanrc@yahoo.com.br     * @param comp_data Compressed cache line.
9813942Sodanrc@yahoo.com.br     * @param cache_line The cache line to be decompressed.
9913942Sodanrc@yahoo.com.br     */
10013942Sodanrc@yahoo.com.br    virtual void decompress(const CompressionData* comp_data,
10113942Sodanrc@yahoo.com.br                              uint64_t* cache_line) = 0;
10213942Sodanrc@yahoo.com.br
10313942Sodanrc@yahoo.com.br  public:
10413942Sodanrc@yahoo.com.br    /** Convenience typedef. */
10513942Sodanrc@yahoo.com.br     typedef BaseCacheCompressorParams Params;
10613942Sodanrc@yahoo.com.br
10713942Sodanrc@yahoo.com.br    /**
10813942Sodanrc@yahoo.com.br     * Default constructor.
10913942Sodanrc@yahoo.com.br     */
11013942Sodanrc@yahoo.com.br    BaseCacheCompressor(const Params *p);
11113942Sodanrc@yahoo.com.br
11213942Sodanrc@yahoo.com.br    /**
11313942Sodanrc@yahoo.com.br     * Default destructor.
11413942Sodanrc@yahoo.com.br     */
11513942Sodanrc@yahoo.com.br    virtual ~BaseCacheCompressor() {};
11613942Sodanrc@yahoo.com.br
11713942Sodanrc@yahoo.com.br    /**
11813942Sodanrc@yahoo.com.br     * Apply the compression process to the cache line. Ignores compression
11913942Sodanrc@yahoo.com.br     * cycles.
12013942Sodanrc@yahoo.com.br     *
12113942Sodanrc@yahoo.com.br     * @param data The cache line to be compressed.
12213942Sodanrc@yahoo.com.br     * @param comp_lat Compression latency in number of cycles.
12313942Sodanrc@yahoo.com.br     * @param decomp_lat Decompression latency in number of cycles.
12413942Sodanrc@yahoo.com.br     * @param comp_size_bits Compressed data size (in bits).
12513942Sodanrc@yahoo.com.br     */
12613942Sodanrc@yahoo.com.br    void compress(const uint64_t* data, Cycles& comp_lat,
12713942Sodanrc@yahoo.com.br                  Cycles& decomp_lat, std::size_t& comp_size_bits);
12813942Sodanrc@yahoo.com.br
12913942Sodanrc@yahoo.com.br    /**
13013942Sodanrc@yahoo.com.br     * Get the decompression latency if the block is compressed. Latency is 0
13113942Sodanrc@yahoo.com.br     * otherwise.
13213942Sodanrc@yahoo.com.br     *
13313942Sodanrc@yahoo.com.br     * @param blk The compressed block.
13413942Sodanrc@yahoo.com.br     */
13513945Sodanrc@yahoo.com.br    Cycles getDecompressionLatency(const CacheBlk* blk) const;
13613942Sodanrc@yahoo.com.br
13713942Sodanrc@yahoo.com.br    /**
13813942Sodanrc@yahoo.com.br     * Set the decompression latency of compressed block.
13913942Sodanrc@yahoo.com.br     *
14013942Sodanrc@yahoo.com.br     * @param blk The compressed block.
14113942Sodanrc@yahoo.com.br     * @param lat The decompression latency.
14213942Sodanrc@yahoo.com.br     */
14313942Sodanrc@yahoo.com.br    static void setDecompressionLatency(CacheBlk* blk, const Cycles lat);
14413942Sodanrc@yahoo.com.br
14513942Sodanrc@yahoo.com.br    /**
14613942Sodanrc@yahoo.com.br     * Set the size of the compressed block, in bits.
14713942Sodanrc@yahoo.com.br     *
14813942Sodanrc@yahoo.com.br     * @param blk The compressed block.
14913942Sodanrc@yahoo.com.br     * @param size_bits The block size.
15013942Sodanrc@yahoo.com.br     */
15113942Sodanrc@yahoo.com.br    static void setSizeBits(CacheBlk* blk, const std::size_t size_bits);
15213943Sodanrc@yahoo.com.br
15313943Sodanrc@yahoo.com.br    /**
15413943Sodanrc@yahoo.com.br     * Register local statistics.
15513943Sodanrc@yahoo.com.br     */
15613943Sodanrc@yahoo.com.br    void regStats() override;
15713942Sodanrc@yahoo.com.br};
15813942Sodanrc@yahoo.com.br
15913942Sodanrc@yahoo.com.brclass BaseCacheCompressor::CompressionData {
16013942Sodanrc@yahoo.com.br  private:
16113942Sodanrc@yahoo.com.br    /**
16213942Sodanrc@yahoo.com.br     * Compressed cache line size (in bits).
16313942Sodanrc@yahoo.com.br     */
16413942Sodanrc@yahoo.com.br    std::size_t _size;
16513942Sodanrc@yahoo.com.br
16613942Sodanrc@yahoo.com.br  public:
16713942Sodanrc@yahoo.com.br    /**
16813942Sodanrc@yahoo.com.br     * Default constructor.
16913942Sodanrc@yahoo.com.br     */
17013942Sodanrc@yahoo.com.br    CompressionData();
17113942Sodanrc@yahoo.com.br
17213942Sodanrc@yahoo.com.br    /**
17313942Sodanrc@yahoo.com.br     * Virtual destructor. Without it unique_ptr will cause mem leak.
17413942Sodanrc@yahoo.com.br     */
17513942Sodanrc@yahoo.com.br    virtual ~CompressionData();
17613942Sodanrc@yahoo.com.br
17713942Sodanrc@yahoo.com.br    /**
17813942Sodanrc@yahoo.com.br     * Set compression size (in bits).
17913942Sodanrc@yahoo.com.br     *
18013942Sodanrc@yahoo.com.br     * @param size Compressed data size.
18113942Sodanrc@yahoo.com.br     */
18213942Sodanrc@yahoo.com.br    void setSizeBits(std::size_t size);
18313942Sodanrc@yahoo.com.br
18413942Sodanrc@yahoo.com.br    /**
18513942Sodanrc@yahoo.com.br     * Get compression size (in bits).
18613942Sodanrc@yahoo.com.br     *
18713942Sodanrc@yahoo.com.br     * @return Compressed data size.
18813942Sodanrc@yahoo.com.br     */
18913942Sodanrc@yahoo.com.br    std::size_t getSizeBits() const;
19013942Sodanrc@yahoo.com.br
19113942Sodanrc@yahoo.com.br    /**
19213942Sodanrc@yahoo.com.br     * Get compression size (in bytes).
19313942Sodanrc@yahoo.com.br     *
19413942Sodanrc@yahoo.com.br     * @return Compressed data size.
19513942Sodanrc@yahoo.com.br     */
19613942Sodanrc@yahoo.com.br    std::size_t getSize() const;
19713942Sodanrc@yahoo.com.br};
19813942Sodanrc@yahoo.com.br
19913942Sodanrc@yahoo.com.br#endif //__MEM_CACHE_COMPRESSORS_BASE_HH__
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