gem5  v20.1.0.0
base_delta_impl.hh
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28 
33 #ifndef __MEM_CACHE_COMPRESSORS_BASE_DELTA_IMPL_HH__
34 #define __MEM_CACHE_COMPRESSORS_BASE_DELTA_IMPL_HH__
35 
36 #include "debug/CacheComp.hh"
39 
40 namespace Compressor {
41 
42 template <class BaseType, std::size_t DeltaSizeBits>
44  : DictionaryCompressor<BaseType>(p)
45 {
46 }
47 
48 template <class BaseType, std::size_t DeltaSizeBits>
49 void
51 {
53 
54  // Add zero base for the immediate values
56 }
57 
58 template <class BaseType, std::size_t DeltaSizeBits>
59 void
61 {
66 }
67 
68 template <class BaseType, std::size_t DeltaSizeBits>
69 std::unique_ptr<Base::CompressionData>
71  const std::vector<Base::Chunk>& chunks, Cycles& comp_lat,
72  Cycles& decomp_lat)
73 {
74  std::unique_ptr<Base::CompressionData> comp_data =
76 
77  // If there are more bases than the maximum, the compressor failed.
78  // Otherwise, we have to take into account all bases that have not
79  // been used, considering that there is an implicit zero base that
80  // does not need to be added to the final size.
81  const int diff = DEFAULT_MAX_NUM_BASES -
83  if (diff < 0) {
85  DPRINTF(CacheComp, "Base%dDelta%d compression failed\n",
86  8 * sizeof(BaseType), DeltaSizeBits);
87  } else if (diff > 0) {
88  comp_data->setSizeBits(comp_data->getSizeBits() +
89  8 * sizeof(BaseType) * diff);
90  }
91 
92  // Set compression latency (Assumes 1 cycle per entry and 1 cycle for
93  // packing)
95  sizeof(BaseType)));
96 
97  // Set decompression latency
98  decomp_lat = Cycles(1);
99 
100  // Return compressed line
101  return comp_data;
102 }
103 
104 } // namespace Compressor
105 
106 #endif //__MEM_CACHE_COMPRESSORS_BASE_DELTA_IMPL_HH__
Compressor::BaseDelta
Base class for all base-delta-immediate compressors.
Definition: base_delta.hh:65
data
const char data[]
Definition: circlebuf.test.cc:42
Compressor
Definition: base.cc:46
Compressor::BaseDelta< uint64_t, 16 >::DictionaryEntry
typename DictionaryCompressor< uint64_t >::DictionaryEntry DictionaryEntry
Definition: base_delta.hh:71
std::vector
STL vector class.
Definition: stl.hh:37
Compressor::BaseDelta::BaseDelta
BaseDelta(const Params *p)
Definition: base_delta_impl.hh:43
Compressor::DictionaryCompressor
A template version of the dictionary compressor that allows to choose the dictionary size.
Definition: dictionary_compressor.hh:112
DPRINTF
#define DPRINTF(x,...)
Definition: trace.hh:234
Compressor::Base::Params
BaseCacheCompressorParams Params
Definition: base.hh:168
dictionary_compressor_impl.hh
Cycles
Cycles is a wrapper class for representing cycle counts, i.e.
Definition: types.hh:83
MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:323
Compressor::Base::setSizeBits
static void setSizeBits(CacheBlk *blk, const std::size_t size_bits)
Set the size of the compressed block, in bits.
Definition: base.cc:200
base_delta.hh

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