src/mem/cache/compressors/Compressors.py

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# Authors: Daniel Carvalho

from m5.params import *
from m5.proxy import *
from m5.SimObject import SimObject

class BaseCacheCompressor(SimObject):
    type = 'BaseCacheCompressor'
    abstract = True
    cxx_header = "mem/cache/compressors/base.hh"

    block_size = Param.Int(Parent.cache_line_size, "Block size in bytes")
    size_threshold = Param.Unsigned(Parent.cache_line_size, "Minimum size, "
        "in bytes, in which a block must be compressed to. Otherwise it is "
        "stored in its uncompressed state")

class BaseDictionaryCompressor(BaseCacheCompressor):
    type = 'BaseDictionaryCompressor'
    abstract = True
    cxx_header = "mem/cache/compressors/dictionary_compressor.hh"

    dictionary_size = Param.Int(Parent.cache_line_size,
        "Number of dictionary entries")

class BDI(BaseCacheCompressor):
    type = 'BDI'
    cxx_class = 'BDI'
    cxx_header = "mem/cache/compressors/bdi.hh"

    use_more_compressors = Param.Bool(True, "True if should use all possible" \
        "combinations of base and delta for the compressors. False if using" \
        "only the lowest possible delta size for each base size.");

class CPack(BaseDictionaryCompressor):
    type = 'CPack'
    cxx_class = 'CPack'
    cxx_header = "mem/cache/compressors/cpack.hh"

class FPCD(BaseDictionaryCompressor):
    type = 'FPCD'
    cxx_class = 'FPCD'
    cxx_header = "mem/cache/compressors/fpcd.hh"

    dictionary_size = 2

class RepeatedQwordsCompressor(BaseDictionaryCompressor):
    type = 'RepeatedQwordsCompressor'
    cxx_class = 'RepeatedQwordsCompressor'
    cxx_header = "mem/cache/compressors/repeated_qwords.hh"

class ZeroCompressor(BaseDictionaryCompressor):
    type = 'ZeroCompressor'
    cxx_class = 'ZeroCompressor'
    cxx_header = "mem/cache/compressors/zero.hh"