| /* |
| * 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. |
| */ |
| |
| #include "mem/ruby/filters/MultiBitSelBloomFilter.hh" |
| |
| #include <vector> |
| |
| #include "base/intmath.hh" |
| #include "base/logging.hh" |
| #include "base/str.hh" |
| |
| using namespace std; |
| |
| MultiBitSelBloomFilter::MultiBitSelBloomFilter(string str) |
| { |
| vector<string> items; |
| tokenize(items, str, '_'); |
| assert(items.size() == 4); |
| |
| // head contains filter size, tail contains bit offset from block number |
| m_filter_size = atoi(items[0].c_str()); |
| m_num_hashes = atoi(items[1].c_str()); |
| m_skip_bits = atoi(items[2].c_str()); |
| |
| if (items[3] == "Regular") { |
| isParallel = false; |
| } else if (items[3] == "Parallel") { |
| isParallel = true; |
| } else { |
| panic("ERROR: Incorrect config string for MultiBitSel Bloom! :%s", |
| str); |
| } |
| |
| m_filter_size_bits = floorLog2(m_filter_size); |
| |
| m_par_filter_size = m_filter_size / m_num_hashes; |
| m_par_filter_size_bits = floorLog2(m_par_filter_size); |
| |
| m_filter.resize(m_filter_size); |
| clear(); |
| } |
| |
| MultiBitSelBloomFilter::~MultiBitSelBloomFilter() |
| { |
| } |
| |
| void |
| MultiBitSelBloomFilter::clear() |
| { |
| for (int i = 0; i < m_filter_size; i++) { |
| m_filter[i] = 0; |
| } |
| } |
| |
| void |
| MultiBitSelBloomFilter::increment(Addr addr) |
| { |
| // Not used |
| } |
| |
| |
| void |
| MultiBitSelBloomFilter::decrement(Addr addr) |
| { |
| // Not used |
| } |
| |
| void |
| MultiBitSelBloomFilter::merge(AbstractBloomFilter *other_filter) |
| { |
| // assumes both filters are the same size! |
| MultiBitSelBloomFilter * temp = (MultiBitSelBloomFilter*) other_filter; |
| for (int i = 0; i < m_filter_size; ++i){ |
| m_filter[i] |= (*temp)[i]; |
| } |
| } |
| |
| void |
| MultiBitSelBloomFilter::set(Addr addr) |
| { |
| for (int i = 0; i < m_num_hashes; i++) { |
| int idx = get_index(addr, i); |
| m_filter[idx] = 1; |
| } |
| } |
| |
| void |
| MultiBitSelBloomFilter::unset(Addr addr) |
| { |
| panic("ERROR: Unset should never be called in a Bloom filter"); |
| } |
| |
| bool |
| MultiBitSelBloomFilter::isSet(Addr addr) |
| { |
| bool res = true; |
| |
| for (int i=0; i < m_num_hashes; i++) { |
| int idx = get_index(addr, i); |
| res = res && m_filter[idx]; |
| } |
| return res; |
| } |
| |
| int |
| MultiBitSelBloomFilter::getCount(Addr addr) |
| { |
| return isSet(addr)? 1: 0; |
| } |
| |
| int |
| MultiBitSelBloomFilter::getIndex(Addr addr) |
| { |
| return 0; |
| } |
| |
| int |
| MultiBitSelBloomFilter::readBit(const int index) |
| { |
| return 0; |
| } |
| |
| void |
| MultiBitSelBloomFilter::writeBit(const int index, const int value) |
| { |
| } |
| |
| int |
| MultiBitSelBloomFilter::getTotalCount() |
| { |
| int count = 0; |
| |
| for (int i = 0; i < m_filter_size; i++) { |
| count += m_filter[i]; |
| } |
| return count; |
| } |
| |
| void |
| MultiBitSelBloomFilter::print(ostream& out) const |
| { |
| } |
| |
| int |
| MultiBitSelBloomFilter::get_index(Addr addr, int i) |
| { |
| // m_skip_bits is used to perform BitSelect after skipping some |
| // bits. Used to simulate BitSel hashing on larger than cache-line |
| // granularities |
| uint64_t x = (makeLineAddress(addr) >> m_skip_bits); |
| int y = hash_bitsel(x, i, m_num_hashes, 30, m_filter_size_bits); |
| //36-bit addresses, 6-bit cache lines |
| |
| if (isParallel) { |
| return (y % m_par_filter_size) + i*m_par_filter_size; |
| } else { |
| return y % m_filter_size; |
| } |
| } |
| |
| int |
| MultiBitSelBloomFilter::hash_bitsel(uint64_t value, int index, int jump, |
| int maxBits, int numBits) |
| { |
| uint64_t mask = 1; |
| int result = 0; |
| int bit, i; |
| |
| for (i = 0; i < numBits; i++) { |
| bit = (index + jump*i) % maxBits; |
| if (value & (mask << bit)) result += mask << i; |
| } |
| return result; |
| } |