irregular_stream_buffer.hh

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#ifndef __MEM_CACHE_PREFETCH_IRREGULAR_STREAM_BUFFER_HH__
#define __MEM_CACHE_PREFETCH_IRREGULAR_STREAM_BUFFER_HH__

#include "base/callback.hh"
#include "base/sat_counter.hh"
#include "mem/cache/prefetch/associative_set.hh"
#include "mem/cache/prefetch/queued.hh"

struct IrregularStreamBufferPrefetcherParams;

class IrregularStreamBufferPrefetcher : public QueuedPrefetcher
{
    const size_t chunkSize;
    const unsigned prefetchCandidatesPerEntry;
    const unsigned degree;

    struct TrainingUnitEntry : public TaggedEntry {
        Addr lastAddress;
        bool lastAddressSecure;
    };
    AssociativeSet<TrainingUnitEntry> trainingUnit;

    struct AddressMapping {
        Addr address;
        SatCounter counter;
        AddressMapping(unsigned bits) : address(0), counter(bits)
        {}
    };

    struct AddressMappingEntry : public TaggedEntry
    {
        std::vector<AddressMapping> mappings;
        AddressMappingEntry(size_t num_mappings, unsigned counter_bits)
          : TaggedEntry(), mappings(num_mappings, counter_bits)
        {
        }

        void
        invalidate() override
        {
            TaggedEntry::invalidate();
            for (auto &entry : mappings) {
                entry.address = 0;
                entry.counter.reset();
            }
        }
    };

    AssociativeSet<AddressMappingEntry> psAddressMappingCache;
    AssociativeSet<AddressMappingEntry> spAddressMappingCache;
    uint64_t structuralAddressCounter;

    void addStructuralToPhysicalEntry(Addr structuralAddress, bool is_secure,
                                      Addr physical_address);

    AddressMapping& getPSMapping(Addr paddr, bool is_secure);
  public:
    IrregularStreamBufferPrefetcher(
        const IrregularStreamBufferPrefetcherParams *p);
    ~IrregularStreamBufferPrefetcher() {}
    void calculatePrefetch(const PrefetchInfo &pfi,
                           std::vector<AddrPriority> &addresses) override;
};
#endif//__MEM_CACHE_PREFETCH_IRREGULAR_STREAM_BUFFER_HH__