fetch_stage.cc

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/*
 * Copyright (c) 2014-2015 Advanced Micro Devices, Inc.
 * All rights reserved.
 *
 * For use for simulation and test purposes only
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 * software without specific prior written permission.
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#include "gpu-compute/fetch_stage.hh"

#include "gpu-compute/compute_unit.hh"
#include "gpu-compute/wavefront.hh"

FetchStage::FetchStage(const ComputeUnitParams* p) : numSIMDs(p->num_SIMDs),
    computeUnit(nullptr)
{
    for (int j = 0; j < numSIMDs; ++j) {
        FetchUnit newFetchUnit(p);
        fetchUnit.push_back(newFetchUnit);
    }
}

FetchStage::~FetchStage()
{
    fetchUnit.clear();
}

void
FetchStage::init(ComputeUnit *cu)
{
    computeUnit = cu;
    _name = computeUnit->name() + ".FetchStage";

    for (int j = 0; j < numSIMDs; ++j) {
        fetchUnit[j].bindWaveList(&computeUnit->wfList[j]);
        fetchUnit[j].init(computeUnit);
    }
}

void
FetchStage::exec()
{
    for (int j = 0; j < numSIMDs; ++j) {
        fetchUnit[j].exec();
    }
}

void
FetchStage::processFetchReturn(PacketPtr pkt)
{
    ComputeUnit::SQCPort::SenderState *sender_state =
        safe_cast<ComputeUnit::SQCPort::SenderState*>(pkt->senderState);

    Wavefront *wavefront = sender_state->wavefront;

    const unsigned num_instructions = pkt->req->getSize() /
        sizeof(TheGpuISA::RawMachInst);

    instFetchInstReturned.sample(num_instructions);
    uint32_t simdId = wavefront->simdId;
    fetchUnit[simdId].processFetchReturn(pkt);
}

void
FetchStage::fetch(PacketPtr pkt, Wavefront *wavefront)
{
    fetchUnit[wavefront->simdId].fetch(pkt, wavefront);
}

void
FetchStage::regStats()
{
    instFetchInstReturned
        .init(1, 32, 1)
        .name(name() + ".inst_fetch_instr_returned")
        .desc("For each instruction fetch request recieved record how many "
              "instructions you got from it")
        ;
}