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Diffstat (limited to 'src/base/filters/multi_bit_sel_bloom_filter.hh')
-rw-r--r-- | src/base/filters/multi_bit_sel_bloom_filter.hh | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/src/base/filters/multi_bit_sel_bloom_filter.hh b/src/base/filters/multi_bit_sel_bloom_filter.hh new file mode 100644 index 000000000..d289bb302 --- /dev/null +++ b/src/base/filters/multi_bit_sel_bloom_filter.hh @@ -0,0 +1,82 @@ +/* + * Copyright (c) 2019 Inria + * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood + * 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. + * + * Authors: Daniel Carvalho + */ + +#ifndef __BASE_FILTERS_MULTI_BIT_SEL_BLOOM_FILTER_HH__ +#define __BASE_FILTERS_MULTI_BIT_SEL_BLOOM_FILTER_HH__ + +#include "base/filters/base.hh" + +struct BloomFilterMultiBitSelParams; + +namespace BloomFilter { + +/** + * The MultiBitSel Bloom Filter associates an address to multiple entries + * through the use of multiple hash functions. + */ +class MultiBitSel : public Base +{ + public: + MultiBitSel(const BloomFilterMultiBitSelParams* p); + ~MultiBitSel(); + + void set(Addr addr) override; + int getCount(Addr addr) const override; + + protected: + /** + * Apply the selected the hash functions to an address. + * + * @param addr The address to hash. + * @param hash_number Index of the hash function to be used. + */ + virtual int hash(Addr addr, int hash_number) const; + + /** Number of hashes. */ + const int numHashes; + + /** Size of the filter when doing parallel hashing. */ + const int parFilterSize; + + /** Whether hashing should be performed in parallel. */ + const bool isParallel; + + private: + /** + * Bit offset from block number. Used to simulate bit selection hashing + * on larger than cache-line granularities, by skipping some bits. + */ + const int skipBits; +}; + +} // namespace BloomFilter + +#endif // __BASE_FILTERS_MULTI_BIT_SEL_BLOOM_FILTER_HH__ |