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+/**
+ * Copyright (c) 2018 Inria
+ * 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.
+ *
+ * Authors: Daniel Carvalho
+ */
+
+/**
+ * @file
+ * Declaration of a Re-Reference Interval Prediction replacement policy.
+ *
+ * Not-Recently Used (NRU) is an approximation of LRU that uses a single bit
+ * to determine if a block is going to be re-referenced in the near or distant
+ * future.
+ *
+ * Re-Reference Interval Prediction (RRIP) is an extension of NRU that uses a
+ * re-reference prediction value to determine if blocks are going to be re-
+ * used in the near future or not.
+ *
+ * The higher the value of the RRPV, the more distant the block is from
+ * its next access.
+ *
+ * Bimodal Re-Reference Interval Prediction (BRRIP) is an extension of RRIP
+ * that has a probability of not inserting blocks as the LRU. This probability
+ * is controlled by the bimodal throtle parameter (btp).
+ *
+ * From the original paper, this implementation of RRIP is also called
+ * Static RRIP (SRRIP), as it always inserts blocks with the same RRPV.
+ */
+
+#ifndef __MEM_CACHE_REPLACEMENT_POLICIES_BRRIP_RP_HH__
+#define __MEM_CACHE_REPLACEMENT_POLICIES_BRRIP_RP_HH__
+
+#include "mem/cache/replacement_policies/base.hh"
+#include "params/BRRIPRP.hh"
+
+class BRRIPRP : public BaseReplacementPolicy
+{
+  protected:
+    /**
+     * Maximum Re-Reference Prediction Value possible. A block with this
+     * value as the rrpv has the longest possible re-reference interval,
+     * that is, it is likely not to be used in the near future, and is
+     * among the best eviction candidates.
+     * A maxRRPV of 1 implies in a NRU.
+     */
+    const unsigned maxRRPV;
+
+    /**
+     * The hit priority (HP) policy replaces blocks that do not receive cache
+     * hits over any cache block that receives a hit, while the frequency
+     * priority (FP) policy replaces infrequently re-referenced blocks.
+     */
+    const bool hitPriority;
+
+    /**
+     * Bimodal throtle parameter. Value in the range [0,100] used to decide
+     * if a new block is inserted with long or distant re-reference.
+     */
+    const unsigned btp;
+
+  public:
+    /** Convenience typedef. */
+    typedef BRRIPRPParams Params;
+
+    /**
+     * Construct and initiliaze this replacement policy.
+     */
+    BRRIPRP(const Params *p);
+
+    /**
+     * Destructor.
+     */
+    ~BRRIPRP() {}
+
+    /**
+     * Touch a block to update its replacement data.
+     *
+     * @param blk Cache block to be touched.
+     */
+    void touch(CacheBlk *blk) override;
+
+    /**
+     * Reset replacement data for a block. Used when a block is inserted.
+     * Sets the insertion tick, and update correspondent replacement data.
+     * Set RRPV according to the insertion policy used.
+     *
+     * @param blk Cache block to be reset.
+     */
+    void reset(CacheBlk *blk) override;
+
+    /**
+     * Find replacement victim using rrpv.
+     *
+     * @param cands Replacement candidates, selected by indexing policy.
+     * @return Cache block to be replaced.
+     */
+    CacheBlk* getVictim(const ReplacementCandidates& candidates) override;
+};
+
+#endif // __MEM_CACHE_REPLACEMENT_POLICIES_BRRIP_RP_HH__