gem5  v21.1.0.2
perfect.cc
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28 
35 
36 #include <algorithm>
37 
38 #include "debug/CacheComp.hh"
39 #include "params/PerfectCompressor.hh"
40 
41 namespace gem5
42 {
43 
44 GEM5_DEPRECATED_NAMESPACE(Compressor, compression);
45 namespace compression
46 {
47 
49  : Base(p), compressedSize(8 * blkSize / p.max_compression_ratio)
50 {
51 }
52 
53 std::unique_ptr<Base::CompressionData>
55  Cycles& comp_lat, Cycles& decomp_lat)
56 {
57  // Compress every word sequentially
58  std::unique_ptr<Base::CompressionData> comp_data(new CompData(chunks));
59 
60  // Set relevant metadata
61  comp_data->setSizeBits(compressedSize);
62 
63  // Set latencies based on the degree of parallelization, and any extra
64  // latencies due to shifting or packaging
65  comp_lat = Cycles((chunks.size() / compChunksPerCycle) + compExtraLatency);
66  decomp_lat = Cycles((chunks.size() / decompChunksPerCycle) +
68 
69  return comp_data;
70 }
71 
72 void
74  uint64_t* data)
75 {
76  // Decompress every entry sequentially
77  fromChunks(static_cast<const CompData*>(comp_data)->chunks, data);
78 }
79 
80 } // namespace compression
81 } // namespace gem5
gem5::compression::Base::CompressionData
Definition: base.hh:246
gem5::compression::Perfect::compress
std::unique_ptr< CompressionData > compress(const std::vector< Chunk > &chunks, Cycles &comp_lat, Cycles &decomp_lat) override
Apply the compression process to the cache line.
Definition: perfect.cc:54
data
const char data[]
Definition: circlebuf.test.cc:48
gem5::compression::Base::decompChunksPerCycle
const Cycles decompChunksPerCycle
Degree of parallelization of the decompression process.
Definition: base.hh:121
gem5::compression::Base::Params
BaseCacheCompressorParams Params
Definition: base.hh:202
std::vector< Chunk >
gem5::compression::Base::compExtraLatency
const Cycles compExtraLatency
Extra latency added to compression due to packaging, shifting or other operations.
Definition: base.hh:115
gem5::compression::Base::fromChunks
void fromChunks(const std::vector< Chunk > &chunks, uint64_t *data) const
This function re-joins the chunks to recreate the original data.
Definition: base.cc:134
gem5::Cycles
Cycles is a wrapper class for representing cycle counts, i.e.
Definition: types.hh:78
gem5::compression::Base::decompExtraLatency
const Cycles decompExtraLatency
Extra latency added to decompression due to packaging, shifting or other operations.
Definition: base.hh:127
perfect.hh
gem5::MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:326
gem5::compression::Base
Base cache compressor interface.
Definition: base.hh:65
gem5::GEM5_DEPRECATED_NAMESPACE
GEM5_DEPRECATED_NAMESPACE(GuestABI, guest_abi)
gem5::compression::Perfect::decompress
void decompress(const CompressionData *comp_data, uint64_t *data) override
Apply the decompression process to the compressed data.
Definition: perfect.cc:73
gem5::compression::Base::compChunksPerCycle
const Cycles compChunksPerCycle
Degree of parallelization of the compression process.
Definition: base.hh:109
gem5::compression::Perfect::CompData
Definition: perfect.hh:79
gem5::compression::Perfect::Perfect
Perfect(const Params &p)
Definition: perfect.cc:48
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40
gem5::compression::Perfect::compressedSize
const int compressedSize
Size to which this compressor always compresses.
Definition: perfect.hh:56

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