| /* |
| * Copyright (c) 2019-2020 Inria |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * 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 |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution; |
| * neither the name of the copyright holders nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| /** @file |
| * Definition of a perfect compressor, that always manages to compress to |
| * its maximum compression ratio. |
| */ |
| |
| #ifndef __MEM_CACHE_COMPRESSORS_PERFECT_COMPRESSOR_HH__ |
| #define __MEM_CACHE_COMPRESSORS_PERFECT_COMPRESSOR_HH__ |
| |
| #include <cstdint> |
| #include <memory> |
| #include <vector> |
| |
| #include "base/types.hh" |
| #include "mem/cache/compressors/base.hh" |
| |
| struct PerfectCompressorParams; |
| |
| namespace Compressor { |
| |
| class Perfect : public Base |
| { |
| protected: |
| class CompData; |
| |
| /** Size to which this compressor always compresses. */ |
| const int compressedSize; |
| |
| /** Number of cycles needed to perform compression. */ |
| const Cycles compressionLatency; |
| |
| /** Number of cycles needed to perform decompression. */ |
| const Cycles decompressionLatency; |
| |
| std::unique_ptr<CompressionData> compress( |
| const std::vector<Chunk>& chunks, Cycles& comp_lat, |
| Cycles& decomp_lat) override; |
| |
| void decompress(const CompressionData* comp_data, uint64_t* data) override; |
| |
| public: |
| typedef PerfectCompressorParams Params; |
| Perfect(const Params *p); |
| ~Perfect() = default; |
| }; |
| |
| class Perfect::CompData : public CompressionData |
| { |
| public: |
| /** The original data is simply copied over to this vector. */ |
| std::vector<Chunk> chunks; |
| |
| /** |
| * Default constructor that creates a copy of the original data. |
| * |
| * @param chunks The data to be compressed. |
| */ |
| CompData(const std::vector<Chunk>& chunks) |
| : CompressionData(), chunks(chunks) |
| { |
| } |
| ~CompData() = default; |
| }; |
| |
| } // namespace Compressor |
| |
| #endif //__MEM_CACHE_COMPRESSORS_PERFECT_COMPRESSOR_HH__ |