multi_bit_sel_bloom_filter.hh revision 14262:991410960fdb
1/* 2 * Copyright (c) 2019 Inria 3 * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are 8 * met: redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer; 10 * redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution; 13 * neither the name of the copyright holders nor the names of its 14 * contributors may be used to endorse or promote products derived from 15 * this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * Authors: Daniel Carvalho 30 */ 31 32#ifndef __BASE_FILTERS_MULTI_BIT_SEL_BLOOM_FILTER_HH__ 33#define __BASE_FILTERS_MULTI_BIT_SEL_BLOOM_FILTER_HH__ 34 35#include "base/filters/base.hh" 36 37struct BloomFilterMultiBitSelParams; 38 39namespace BloomFilter { 40 41/** 42 * The MultiBitSel Bloom Filter associates an address to multiple entries 43 * through the use of multiple hash functions. 44 */ 45class MultiBitSel : public Base 46{ 47 public: 48 MultiBitSel(const BloomFilterMultiBitSelParams* p); 49 ~MultiBitSel(); 50 51 void set(Addr addr) override; 52 int getCount(Addr addr) const override; 53 54 protected: 55 /** 56 * Apply the selected the hash functions to an address. 57 * 58 * @param addr The address to hash. 59 * @param hash_number Index of the hash function to be used. 60 */ 61 virtual int hash(Addr addr, int hash_number) const; 62 63 /** Number of hashes. */ 64 const int numHashes; 65 66 /** Size of the filter when doing parallel hashing. */ 67 const int parFilterSize; 68 69 /** Whether hashing should be performed in parallel. */ 70 const bool isParallel; 71 72 private: 73 /** 74 * Bit offset from block number. Used to simulate bit selection hashing 75 * on larger than cache-line granularities, by skipping some bits. 76 */ 77 const int skipBits; 78}; 79 80} // namespace BloomFilter 81 82#endif // __BASE_FILTERS_MULTI_BIT_SEL_BLOOM_FILTER_HH__ 83