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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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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 * Authors: Anthony Gutierrez,
 *          Sooraj Puthoor
 */

#ifndef __FETCH_STAGE_HH__
#define __FETCH_STAGE_HH__

#include <string>
#include <vector>

#include "gpu-compute/fetch_unit.hh"

// 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* params);
    ~FetchStage();
    void init(ComputeUnit *cu);
    void exec();
    void processFetchReturn(PacketPtr pkt);
    void fetch(PacketPtr pkt, Wavefront *wave);

    // Stats related variables and methods
    std::string name() { return _name; }
    void regStats();
    Stats::Distribution instFetchInstReturned;

  private:
    uint32_t numSIMDs;
    ComputeUnit *computeUnit;

    // List of fetch units. A fetch unit is
    // instantiated per SIMD
    std::vector<FetchUnit> fetchUnit;
    std::string _name;
};

#endif // __FETCH_STAGE_HH__