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28 * Authors: Daniel Carvalho
33 * Declaration of a random replacement policy.
34 * The victim is chosen at random, if there are no invalid entries.
37 #ifndef __MEM_CACHE_REPLACEMENT_POLICIES_RANDOM_RP_HH__
38 #define __MEM_CACHE_REPLACEMENT_POLICIES_RANDOM_RP_HH__
40 #include "mem/cache/replacement_policies/base.hh"
42 struct RandomRPParams;
44 class RandomRP : public BaseReplacementPolicy
47 /** MRU-specific implementation of replacement data. */
48 struct RandomReplData : ReplacementData
51 * Flag informing if the replacement data is valid or not.
52 * Invalid entries are prioritized to be evicted.
57 * Default constructor. Invalidate data.
59 RandomReplData() : valid(false) {}
63 /** Convenience typedef. */
64 typedef RandomRPParams Params;
67 * Construct and initiliaze this replacement policy.
69 RandomRP(const Params *p);
77 * Invalidate replacement data to set it as the next probable victim.
78 * Prioritize replacement data for victimization.
80 * @param replacement_data Replacement data to be invalidated.
82 void invalidate(const std::shared_ptr<ReplacementData>& replacement_data)
86 * Touch an entry to update its replacement data.
87 * Does not do anything.
89 * @param replacement_data Replacement data to be touched.
91 void touch(const std::shared_ptr<ReplacementData>& replacement_data) const
95 * Reset replacement data. Used when an entry is inserted.
96 * Unprioritize replacement data for victimization.
98 * @param replacement_data Replacement data to be reset.
100 void reset(const std::shared_ptr<ReplacementData>& replacement_data) const
104 * Find replacement victim at random.
106 * @param candidates Replacement candidates, selected by indexing policy.
107 * @return Replacement entry to be replaced.
109 ReplaceableEntry* getVictim(const ReplacementCandidates& candidates) const
113 * Instantiate a replacement data entry.
115 * @return A shared pointer to the new replacement data.
117 std::shared_ptr<ReplacementData> instantiateEntry() override;
120 #endif // __MEM_CACHE_REPLACEMENT_POLICIES_RANDOM_RP_HH__