fetch_stage.hh

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/*
 * Copyright (c) 2014-2015 Advanced Micro Devices, Inc.
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 * For use for simulation and test purposes only
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#ifndef __FETCH_STAGE_HH__
#define __FETCH_STAGE_HH__
 
#include <string>
#include <vector>
 
#include "base/statistics.hh"
#include "base/stats/group.hh"
#include "gpu-compute/fetch_unit.hh"
 
namespace gem5
{
 
// Instruction fetch stage.
// All dispatched wavefronts for all SIMDS are analyzed for the
// need to fetch instructions. From the fetch eligible waves,
// one wave is selected from each SIMD and fetch is initiated
// for the selected waves.
 
class ComputeUnit;
class Wavefront;
 
class FetchStage
{
  public:
    FetchStage(const ComputeUnitParams &p, ComputeUnit &cu);
    ~FetchStage();
    void init();
    void exec();
    void processFetchReturn(PacketPtr pkt);
    void fetch(PacketPtr pkt, Wavefront *wave);
 
    // Stats related variables and methods
    const std::string& name() const { return _name; }
    FetchUnit &fetchUnit(int simdId) { return _fetchUnit.at(simdId); }
 
  private:
    int numVectorALUs;
    ComputeUnit &computeUnit;
 
    // List of fetch units. A fetch unit is
    // instantiated per VALU/SIMD
    std::vector<FetchUnit> _fetchUnit;
    const std::string _name;
 
  protected:
    struct FetchStageStats : public statistics::Group
    {
        FetchStageStats(statistics::Group *parent);
 
        statistics::Distribution instFetchInstReturned;
    } stats;
};
 
} // namespace gem5
 
#endif // __FETCH_STAGE_HH__