stride.hh

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/*
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#ifndef __MEM_CACHE_PREFETCH_STRIDE_HH__
#define __MEM_CACHE_PREFETCH_STRIDE_HH__
 
#include <string>
#include <unordered_map>
#include <vector>
 
#include "base/cache/associative_cache.hh"
#include "base/sat_counter.hh"
#include "base/types.hh"
#include "mem/cache/prefetch/queued.hh"
#include "mem/cache/replacement_policies/replaceable_entry.hh"
#include "mem/cache/tags/indexing_policies/set_associative.hh"
#include "mem/cache/tags/tagged_entry.hh"
#include "mem/packet.hh"
#include "params/StridePrefetcherHashedSetAssociative.hh"
 
namespace gem5
{
 
namespace replacement_policy
{
    class Base;
}
namespace replacement_policy {…}
struct StridePrefetcherParams;
 
namespace prefetch
{
 
class StridePrefetcherHashedSetAssociative : public TaggedSetAssociative
{
  protected:
    uint32_t extractSet(const KeyType &key) const override;
    Addr extractTag(const Addr addr) const override;
 
  public:
    StridePrefetcherHashedSetAssociative(
        const StridePrefetcherHashedSetAssociativeParams &p)
      : TaggedSetAssociative(p)
    {
    }
    StridePrefetcherHashedSetAssociative( {…}
    ~StridePrefetcherHashedSetAssociative() = default;
};
class StridePrefetcherHashedSetAssociative : public TaggedSetAssociative {…};
 
class Stride : public Queued
{
  protected:
    const SatCounter8 initConfidence;
 
    const double threshConf;
 
    const bool useRequestorId;
 
    const int degree;
 
    const int distance;
 
    const struct PCTableInfo
    {
        const int assoc;
        const int numEntries;
 
        TaggedIndexingPolicy* const indexingPolicy;
        replacement_policy::Base* const replacementPolicy;
 
        PCTableInfo(int assoc, int num_entries,
                    TaggedIndexingPolicy* indexing_policy,
                    replacement_policy::Base* repl_policy)
          : assoc(assoc), numEntries(num_entries),
            indexingPolicy(indexing_policy), replacementPolicy(repl_policy)
        {
        }
        PCTableInfo(int assoc, int num_entries, {…}
    } pcTableInfo;
    const struct PCTableInfo {…};
 
    struct StrideEntry : public TaggedEntry
    {
        StrideEntry(const SatCounter8& init_confidence, TagExtractor ext);
 
        void invalidate() override;
 
        Addr lastAddr;
        int stride;
        SatCounter8 confidence;
    };
    struct StrideEntry : public TaggedEntry {…};
    using PCTable = AssociativeCache<StrideEntry>;
    std::unordered_map<int, std::unique_ptr<PCTable>> pcTables;
 
    const bool useCachelineAddr;
 
    PCTable& findTable(int context);
 
    PCTable& allocateNewContext(int context);
 
  public:
    Stride(const StridePrefetcherParams &p);
 
    void calculatePrefetch(const PrefetchInfo &pfi,
                           std::vector<AddrPriority> &addresses,
                           const CacheAccessor &cache) override;
};
class Stride : public Queued {…};
 
} // namespace prefetch
} // namespace gem5
 
#endif // __MEM_CACHE_PREFETCH_STRIDE_HH__