src/mem/ruby/filters/NonCountingBloomFilter.cc

   1 /*
   2  * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "base/intmath.hh"
  30 #include "base/str.hh"
  31 #include "mem/ruby/filters/NonCountingBloomFilter.hh"
  32 #include "mem/ruby/system/System.hh"
  33
  34 using namespace std;
  35
  36 NonCountingBloomFilter::NonCountingBloomFilter(string str)
  37 {
  38     string head, tail;
  39 #ifndef NDEBUG
  40     bool success =
  41 #endif
  42         split_first(str, head, tail, '_');
  43     assert(success);
  44
  45     // head contains filter size, tail contains bit offset from block number
  46     m_filter_size = atoi(head.c_str());
  47     m_offset = atoi(tail.c_str());
  48     m_filter_size_bits = floorLog2(m_filter_size);
  49
  50     m_filter.resize(m_filter_size);
  51     clear();
  52 }
  53
  54 NonCountingBloomFilter::~NonCountingBloomFilter()
  55 {
  56 }
  57
  58 void
  59 NonCountingBloomFilter::clear()
  60 {
  61     for (int i = 0; i < m_filter_size; i++) {
  62         m_filter[i] = 0;
  63     }
  64 }
  65
  66 void
  67 NonCountingBloomFilter::increment(const Address& addr)
  68 {
  69     // Not used
  70 }
  71
  72 void
  73 NonCountingBloomFilter::decrement(const Address& addr)
  74 {
  75     // Not used
  76 }
  77
  78 void
  79 NonCountingBloomFilter::merge(AbstractBloomFilter *other_filter)
  80 {
  81     // assumes both filters are the same size!
  82     NonCountingBloomFilter * temp = (NonCountingBloomFilter*) other_filter;
  83     for(int i = 0; i < m_filter_size; ++i){
  84         m_filter[i] |= (*temp)[i];
  85     }
  86 }
  87
  88 void
  89 NonCountingBloomFilter::set(const Address& addr)
  90 {
  91     int i = get_index(addr);
  92     m_filter[i] = 1;
  93 }
  94
  95 void
  96 NonCountingBloomFilter::unset(const Address& addr)
  97 {
  98     int i = get_index(addr);
  99     m_filter[i] = 0;
 100 }
 101
 102 bool
 103 NonCountingBloomFilter::isSet(const Address& addr)
 104 {
 105     int i = get_index(addr);
 106     return (m_filter[i]);
 107 }
 108
 109
 110 int
 111 NonCountingBloomFilter::getCount(const Address& addr)
 112 {
 113     return m_filter[get_index(addr)];
 114 }
 115
 116 int
 117 NonCountingBloomFilter::getTotalCount()
 118 {
 119     int count = 0;
 120
 121     for (int i = 0; i < m_filter_size; i++) {
 122         count += m_filter[i];
 123     }
 124     return count;
 125 }
 126
 127 void
 128 NonCountingBloomFilter::print(ostream& out) const
 129 {
 130 }
 131
 132 int
 133 NonCountingBloomFilter::getIndex(const Address& addr)
 134 {
 135     return get_index(addr);
 136 }
 137
 138 int
 139 NonCountingBloomFilter::readBit(const int index)
 140 {
 141     return m_filter[index];
 142 }
 143
 144 void
 145 NonCountingBloomFilter::writeBit(const int index, const int value)
 146 {
 147     m_filter[index] = value;
 148 }
 149
 150 int
 151 NonCountingBloomFilter::get_index(const Address& addr)
 152 {
 153     return addr.bitSelect(RubySystem::getBlockSizeBits() + m_offset,
 154                           RubySystem::getBlockSizeBits() + m_offset +
 155                           m_filter_size_bits - 1);
 156 }
 157
 158