gem5  v20.1.0.0
fpcd.cc
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28 
34 
36 #include "params/FPCD.hh"
37 
38 namespace Compressor {
39 
41  : DictionaryCompressor<uint32_t>(p)
42 {
43 }
44 
45 void
47 {
48  // The dictionary behaves as a table with FIFO as replacement policy
49  if (numEntries == 2) {
52  } else {
54  }
55 }
56 
57 std::unique_ptr<Base::CompressionData>
59  Cycles& comp_lat, Cycles& decomp_lat)
60 {
61  std::unique_ptr<Base::CompressionData> comp_data =
63 
64  // Set compression latency (Accounts for zero checks, ones check, match
65  // previous check, match penultimate check, repeated values check, pattern
66  // selection, shifting, at a rate of 16B per cycle)
67  comp_lat = Cycles(blkSize/2);
68 
69  // Set decompression latency. The original claim of 2 cycles is likely
70  // too unrealistic
71  decomp_lat = Cycles(4);
72 
73  // Return compressed line
74  return comp_data;
75 }
76 
77 } // namespace Compressor
78 
80 FPCDParams::create()
81 {
82  return new Compressor::FPCD(this);
83 }
Compressor::FPCD::addToDictionary
void addToDictionary(DictionaryEntry data) override
Definition: fpcd.cc:46
data
const char data[]
Definition: circlebuf.test.cc:42
fpcd.hh
Compressor::Base::blkSize
const std::size_t blkSize
Uncompressed cache line size (in bytes).
Definition: base.hh:87
Compressor
Definition: base.cc:46
Compressor::FPCD::compress
std::unique_ptr< Base::CompressionData > compress(const std::vector< Base::Chunk > &chunks, Cycles &comp_lat, Cycles &decomp_lat) override
Apply the compression process to the cache line.
Definition: fpcd.cc:58
Compressor::DictionaryCompressor::compress
std::unique_ptr< Base::CompressionData > compress(const std::vector< Chunk > &chunks)
Apply compression.
Definition: dictionary_compressor_impl.hh:126
std::vector< Chunk >
Compressor::BaseDictionaryCompressor::numEntries
std::size_t numEntries
Number of valid entries in the dictionary.
Definition: dictionary_compressor.hh:69
Compressor::FPCD::penultimateIndex
static constexpr int penultimateIndex
Index of the penultimate dictionary entry.
Definition: fpcd.hh:66
Compressor::FPCD::FPCD
FPCD(const Params *p)
Definition: fpcd.cc:40
Compressor::DictionaryCompressor
A template version of the dictionary compressor that allows to choose the dictionary size.
Definition: dictionary_compressor.hh:112
Compressor::Base::Params
BaseCacheCompressorParams Params
Definition: base.hh:168
Compressor::FPCD::DictionaryEntry
DictionaryCompressor< uint32_t >::DictionaryEntry DictionaryEntry
Definition: fpcd.hh:57
dictionary_compressor_impl.hh
Compressor::FPCD::previousIndex
static constexpr int previousIndex
Index of the previous dictionary entry.
Definition: fpcd.hh:63
Cycles
Cycles is a wrapper class for representing cycle counts, i.e.
Definition: types.hh:83
Compressor::DictionaryCompressor< uint32_t >::dictionary
std::vector< DictionaryEntry > dictionary
The dictionary.
Definition: dictionary_compressor.hh:187
Compressor::FPCD
Definition: fpcd.hh:54
MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:323

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