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===== Software accelerator (sample code) =====
<code c++ swacc.cpp>
/* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* ***************************************************************************
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as 
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 *  As a special exception, you may use this file as part of a free software
 *  library without restriction.  Specifically, if other files instantiate
 *  templates or use macros or inline functions from this file, or you compile
 *  this file and link it with other files to produce an executable, this
 *  file does not by itself cause the resulting executable to be covered by
 *  the GNU General Public License.  This exception does not however
 *  invalidate any other reasons why the executable file might be covered by
 *  the GNU General Public License.
 *
 ****************************************************************************
 */

/*
 * Very basic test for the FastFlow farm in the accelerator configuration.
 *
 */
#include <vector>
#include <iostream>
#include <ff/farm.hpp>
  
using namespace ff;

// generic worker
class Worker: public ff_node {
public:
    void * svc(void * task) {
        long *t = (long *)task;
        printf("Worker(%d): received task %ld\n", get_my_id(),*t);
        return task;
    }
};

class Collector: public ff_node {
public:
    void * svc(void * task) { return task; }
};


int main(int argc, char * argv[]) {
    if (argc<3) {
        std::cerr << "use: " << argv[0] << " nworkers streamlen\n";
        return -1;
    }
    
    int nworkers=atoi(argv[1]);
    int streamlen=atoi(argv[2]);
    
    ff_farm<> farm(true);  // accelerator set
    std::vector<ff_node *> w;
    for(int i=0;i<nworkers;++i) w.push_back(new Worker);
    farm.add_workers(w);
    farm.add_collector(new Collector);

    ffTime(START_TIME);
    // Now run the accelator asynchronusly
    farm.run_then_freeze(); //  farm.run() can also be used here

    void * result=NULL;
    for (int i=0;i<streamlen;i++) {
        std::cout << "Offloading task " << i << "\n"; 
        // Here offloading computation onto the farm
        farm.offload(new long(i)); 

        // try to get results, if there are any
        if (farm.load_result_nb(&result)) {
            std::cerr << "result= " << *((long*)result) << "\n";
            delete ((long*)result);
        }
    }
    std::cout << "Offloading EOS\n";
    farm.offload((void *)FF_EOS);
   
#if 1
    // get all remaining results syncronously. 
    while(farm.load_result(&result)) {
        std::cerr << "result= " << *((long*)result) << "\n";
        delete ((long*)result);
    }
#else 
    // asynchronously wait results
    do {
        if (farm.load_result_nb(&result)) {
            if (result==(void*)FF_EOS) break;
            std::cerr << "result= " << *((long*)result) << "\n";
            delete ((long*)result);
        } 
        // do something useful here....

    } while(1);
#endif
    
    // Here join
    farm.wait();  
    ffTime(STOP_TIME);
    std::cerr << "[Main] DONE, farm time= " << farm.ffTime() << " (ms)\n";
    std::cerr << "[Main] DONE, total time= " << ffTime(GET_TIME) << " (ms)\n";
    return 0;
}
</code>