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+/*
+ * Copyright (c) 2007 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.
+ */
+
+#ifndef __MEM_RUBY_SYSTEM_LRUPOLICY_HH__
+#define __MEM_RUBY_SYSTEM_LRUPOLICY_HH__
+
+#include "mem/ruby/structures/AbstractReplacementPolicy.hh"
+
+/* Simple true LRU replacement policy */
+
+class LRUPolicy : public AbstractReplacementPolicy
+{
+ public:
+ LRUPolicy(Index num_sets, Index assoc);
+ ~LRUPolicy();
+
+ void touch(Index set, Index way, Tick time);
+ Index getVictim(Index set) const;
+};
+
+inline
+LRUPolicy::LRUPolicy(Index num_sets, Index assoc)
+ : AbstractReplacementPolicy(num_sets, assoc)
+{
+}
+
+inline
+LRUPolicy::~LRUPolicy()
+{
+}
+
+inline void
+LRUPolicy::touch(Index set, Index index, Tick time)
+{
+ assert(index >= 0 && index < m_assoc);
+ assert(set >= 0 && set < m_num_sets);
+
+ m_last_ref_ptr[set][index] = time;
+}
+
+inline Index
+LRUPolicy::getVictim(Index set) const
+{
+ // assert(m_assoc != 0);
+ Tick time, smallest_time;
+ Index smallest_index;
+
+ smallest_index = 0;
+ smallest_time = m_last_ref_ptr[set][0];
+
+ for (unsigned i = 0; i < m_assoc; i++) {
+ time = m_last_ref_ptr[set][i];
+ // assert(m_cache[cacheSet][i].m_Permission !=
+ // AccessPermission_NotPresent);
+
+ if (time < smallest_time) {
+ smallest_index = i;
+ smallest_time = time;
+ }
+ }
+
+ // DEBUG_EXPR(CACHE_COMP, MedPrio, cacheSet);
+ // DEBUG_EXPR(CACHE_COMP, MedPrio, smallest_index);
+ // DEBUG_EXPR(CACHE_COMP, MedPrio, m_cache[cacheSet][smallest_index]);
+ // DEBUG_EXPR(CACHE_COMP, MedPrio, *this);
+
+ return smallest_index;
+}
+
+#endif // __MEM_RUBY_SYSTEM_LRUPOLICY_HH__