95 lines
3.1 KiB
C++
95 lines
3.1 KiB
C++
/*
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* Copyright (c) 2007 Mark D. Hill and David A. Wood
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are
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* met: redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer;
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* redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution;
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* neither the name of the copyright holders nor the names of its
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* contributors may be used to endorse or promote products derived from
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* this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#ifndef __MEM_RUBY_SYSTEM_LRUPOLICY_HH__
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#define __MEM_RUBY_SYSTEM_LRUPOLICY_HH__
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#include "mem/ruby/system/AbstractReplacementPolicy.hh"
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/* Simple true LRU replacement policy */
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class LRUPolicy : public AbstractReplacementPolicy
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{
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public:
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LRUPolicy(Index num_sets, Index assoc);
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~LRUPolicy();
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void touch(Index set, Index way, Tick time);
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Index getVictim(Index set) const;
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};
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inline
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LRUPolicy::LRUPolicy(Index num_sets, Index assoc)
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: AbstractReplacementPolicy(num_sets, assoc)
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{
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}
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inline
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LRUPolicy::~LRUPolicy()
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{
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}
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inline void
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LRUPolicy::touch(Index set, Index index, Tick time)
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{
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assert(index >= 0 && index < m_assoc);
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assert(set >= 0 && set < m_num_sets);
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m_last_ref_ptr[set][index] = time;
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}
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inline Index
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LRUPolicy::getVictim(Index set) const
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{
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// assert(m_assoc != 0);
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Tick time, smallest_time;
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Index smallest_index;
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smallest_index = 0;
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smallest_time = m_last_ref_ptr[set][0];
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for (unsigned i = 0; i < m_assoc; i++) {
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time = m_last_ref_ptr[set][i];
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// assert(m_cache[cacheSet][i].m_Permission !=
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// AccessPermission_NotPresent);
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if (time < smallest_time) {
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smallest_index = i;
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smallest_time = time;
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}
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}
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// DEBUG_EXPR(CACHE_COMP, MedPrio, cacheSet);
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// DEBUG_EXPR(CACHE_COMP, MedPrio, smallest_index);
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// DEBUG_EXPR(CACHE_COMP, MedPrio, m_cache[cacheSet][smallest_index]);
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// DEBUG_EXPR(CACHE_COMP, MedPrio, *this);
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return smallest_index;
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}
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#endif // __MEM_RUBY_SYSTEM_LRUPOLICY_HH__
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