/* * 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. */ /* * BulkBloomFilter.cc * * Description: * * */ #include "mem/ruby/filters/BulkBloomFilter.hh" #include "mem/gems_common/Map.hh" #include "mem/ruby/common/Address.hh" BulkBloomFilter::BulkBloomFilter(string str) { string tail(str); string head = string_split(tail, '_'); m_filter_size = atoi(head.c_str()); m_filter_size_bits = log_int(m_filter_size); // split the filter bits in half, c0 and c1 m_sector_bits = m_filter_size_bits - 1; m_temp_filter.setSize(m_filter_size); m_filter.setSize(m_filter_size); clear(); // clear temp filter for(int i=0; i < m_filter_size; ++i){ m_temp_filter[i] = 0; } } BulkBloomFilter::~BulkBloomFilter(){ } void BulkBloomFilter::clear() { for (int i = 0; i < m_filter_size; i++) { m_filter[i] = 0; } } void BulkBloomFilter::increment(const Address& addr) { // Not used } void BulkBloomFilter::decrement(const Address& addr) { // Not used } void BulkBloomFilter::merge(AbstractBloomFilter * other_filter) { // TODO } void BulkBloomFilter::set(const Address& addr) { // c0 contains the cache index bits int set_bits = m_sector_bits; int block_bits = RubySystem::getBlockSizeBits(); int c0 = addr.bitSelect( block_bits, block_bits + set_bits - 1); // c1 contains the lower m_sector_bits permuted bits //Address permuted_bits = permute(addr); //int c1 = permuted_bits.bitSelect(0, set_bits-1); int c1 = addr.bitSelect( block_bits+set_bits, (block_bits+2*set_bits) - 1); //ASSERT(c0 < (m_filter_size/2)); //ASSERT(c0 + (m_filter_size/2) < m_filter_size); //ASSERT(c1 < (m_filter_size/2)); // set v0 bit m_filter[c0 + (m_filter_size/2)] = 1; // set v1 bit m_filter[c1] = 1; } void BulkBloomFilter::unset(const Address& addr) { // not used } bool BulkBloomFilter::isSet(const Address& addr) { // c0 contains the cache index bits int set_bits = m_sector_bits; int block_bits = RubySystem::getBlockSizeBits(); int c0 = addr.bitSelect( block_bits, block_bits + set_bits - 1); // c1 contains the lower 10 permuted bits //Address permuted_bits = permute(addr); //int c1 = permuted_bits.bitSelect(0, set_bits-1); int c1 = addr.bitSelect( block_bits+set_bits, (block_bits+2*set_bits) - 1); //ASSERT(c0 < (m_filter_size/2)); //ASSERT(c0 + (m_filter_size/2) < m_filter_size); //ASSERT(c1 < (m_filter_size/2)); // set v0 bit m_temp_filter[c0 + (m_filter_size/2)] = 1; // set v1 bit m_temp_filter[c1] = 1; // perform filter intersection. If any c part is 0, no possibility of address being in signature. // get first c intersection part bool zero = false; for(int i=0; i < m_filter_size/2; ++i){ // get intersection of signatures m_temp_filter[i] = m_temp_filter[i] && m_filter[i]; zero = zero || m_temp_filter[i]; } zero = !zero; if(zero){ // one section is zero, no possiblility of address in signature // reset bits we just set m_temp_filter[c0 + (m_filter_size/2)] = 0; m_temp_filter[c1] = 0; return false; } // check second section zero = false; for(int i=m_filter_size/2; i < m_filter_size; ++i){ // get intersection of signatures m_temp_filter[i] = m_temp_filter[i] && m_filter[i]; zero = zero || m_temp_filter[i]; } zero = !zero; if(zero){ // one section is zero, no possiblility of address in signature m_temp_filter[c0 + (m_filter_size/2)] = 0; m_temp_filter[c1] = 0; return false; } // one section has at least one bit set m_temp_filter[c0 + (m_filter_size/2)] = 0; m_temp_filter[c1] = 0; return true; } int BulkBloomFilter::getCount(const Address& addr) { // not used return 0; } int BulkBloomFilter::getTotalCount() { int count = 0; for (int i = 0; i < m_filter_size; i++) { if (m_filter[i]) { count++; } } return count; } int BulkBloomFilter::getIndex(const Address& addr) { return get_index(addr); } int BulkBloomFilter::readBit(const int index) { return 0; // TODO } void BulkBloomFilter::writeBit(const int index, const int value) { // TODO } void BulkBloomFilter::print(ostream& out) const { } int BulkBloomFilter::get_index(const Address& addr) { return addr.bitSelect( RubySystem::getBlockSizeBits(), RubySystem::getBlockSizeBits() + m_filter_size_bits - 1); } Address BulkBloomFilter::permute(const Address & addr){ // permutes the original address bits according to Table 5 int block_offset = RubySystem::getBlockSizeBits(); physical_address_t part1 = addr.bitSelect( block_offset, block_offset + 6 ); physical_address_t part2 = addr.bitSelect( block_offset + 9, block_offset + 9 ); physical_address_t part3 = addr.bitSelect( block_offset + 11, block_offset + 11 ); physical_address_t part4 = addr.bitSelect( block_offset + 17, block_offset + 17 ); physical_address_t part5 = addr.bitSelect( block_offset + 7, block_offset + 8 ); physical_address_t part6 = addr.bitSelect( block_offset + 10, block_offset + 10 ); physical_address_t part7 = addr.bitSelect( block_offset + 12, block_offset + 12 ); physical_address_t part8 = addr.bitSelect( block_offset + 13, block_offset + 13 ); physical_address_t part9 = addr.bitSelect( block_offset + 15, block_offset + 16 ); physical_address_t part10 = addr.bitSelect( block_offset + 18, block_offset + 20 ); physical_address_t part11 = addr.bitSelect( block_offset + 14, block_offset + 14 ); physical_address_t result = (part1 << 14 ) | (part2 << 13 ) | (part3 << 12 ) | (part4 << 11 ) | (part5 << 9) | (part6 << 8) | (part7 << 7) | (part8 << 6) | (part9 << 4) | (part10 << 1) | (part11); // assume 32 bit addresses (both virtual and physical) // select the remaining high-order 11 bits physical_address_t remaining_bits = (addr.bitSelect( block_offset + 21, 31 )) << 21; result = result | remaining_bits; return Address(result); }