PathFinder.hpp

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// Torc - Copyright 2011-2013 University of Southern California.  All Rights Reserved.
// $HeadURL$
// $Id$

// This program is free software: you can redistribute it and/or modify it under the terms of the 
// GNU General Public License as published by the Free Software Foundation, either version 3 of the 
// License, or (at your option) any later version.
// 
// 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, see <http://www.gnu.org/licenses/>.

#ifndef TORC_ROUTER_PATHFINDER_HPP
#define TORC_ROUTER_PATHFINDER_HPP

#include "torc/architecture/DDB.hpp"
#include "NetRouterBase.hpp"
#include "NetVectorRouterHeuristicBase.hpp"
#include "RouteNet.hpp"
#include "RouteNode.hpp"
#include <boost/functional/hash.hpp>


#include <iostream>
#include <fstream>
#include <vector>
#include <list>
#include <map>
#include <algorithm>
#include "NetVectorRouterBase.hpp"
#include <boost/timer.hpp>
#include <boost/unordered_map.hpp>
#include <boost/functional/hash.hpp>
#include <boost/cstdint.hpp>

#include "torc/architecture/Tilewire.hpp"

namespace torc {

namespace router {
    /// \brief Pathfinder annotations for Tilewires.
    struct TilewireData {
        boost::uint32_t mPresentSharing;
        boost::uint32_t mHistorySharing;
    };

    class PathFinder : public NetVectorRouterBase
    {
        typedef std::string string;
        typedef architecture::DDB DDB;
        typedef architecture::WireUsage WireUsage;
        typedef architecture::Tilewire Tilewire;
        typedef architecture::Arc Arc;
        typedef architecture::TilewireVector TilewireVector;
        typedef TilewireVector::const_iterator TilewireConstIterator;
        
        typedef boost::unordered_map<Tilewire, TilewireData> PathFinderSharingMap;
        
    protected:
    
        PathFinderSharingMap mConflicts;
        WireUsage mConflictWireUsage;
        
        TilewireVector mTempWireSources;
        TilewireVector mTempWireSinks;
        
        boost::timer routetimer;
        boost::timer iterationtimer;
        boost::timer totaltimer;
        boost::timer updatetimer;
        
        long deleteCount;
        
    public:
        /// \brief Pathfinder constructor.
        PathFinder(DDB& inDB, NetVectorRouterHeuristicBase* inHeuristic,
            NetRouterBase* inNetRouter) : NetVectorRouterBase(inDB, inHeuristic, inNetRouter), 
            mConflictWireUsage(mDB.getTiles()) {
            
            mTempWireSources.reserve(200);
            mTempWireSinks.reserve(200);
            mTempWireSources.clear();
            mTempWireSinks.clear();
            deleteCount = 0;
            
            mConflictWireUsage.autosize();
            mNetRouter->getHeuristic()->setParameter(0, &mConflicts);
            mNetRouter->getHeuristic()->processParameters();
        }
        
        /// \brief Destructor.
        ~PathFinder() {}

        void routeNets(RouteNetVector& nets) {
            
            bool flag_resources = true;
            
            unsigned int numNets = nets.size();
            
            flag_resources = true;

            int routingPasses = 0;


            // Initial Routes
            totaltimer.restart();
            double updatetime = 0;
            iterationtimer.restart();
            for (unsigned int i = 0; i < numNets; i++) {
                RouteNet& net = nets[i];
            
                //double routetime;
                if (!(net.hasOneSource() && net.hasAnySinks())) {
                    std::cout << "BAD NET: " << net.getName() << std::endl;
                    continue;
                }
                try {
                    //std::cout << "### Routing net " << net.getName() << " " 
                    //  << " index: " << i << " of " << numNets 
                    //  << std::endl;
                    routetimer.restart();
                    unmarkSourcesAndSinks(net);
                    mNetRouter->route(net);
                    markSourcesAndSinks(net);
                    updateSharing(net.routeNodes());
                    //routetime = routetimer.elapsed();
                }
                catch (...) {
                        std::cout << "Failed routing net " << i << ": " << std::endl;
                        throw;
                }
                mConflictWireUsage.clear();
            }

            mConflicts.clear();
            std::cout << "Initial routes time: " << iterationtimer.elapsed() << std::endl;

            for (unsigned int i = 0; i < numNets; i++) {
                for (unsigned int j = 0; j < nets[i].routeNodes().size(); j++) {
                    updateSharing(nets[i].routeNodes()[j]->getSinkTilewire());
                }
            }
            
            // Main Loop
            while (flag_resources) { // while shared resources exist
                iterationtimer.restart();
                std::cout << "." << std::flush;
                        
                double avgroutetime = 0;
                double minroutetime = std::numeric_limits<double>::max();
                double maxroutetime = std::numeric_limits<double>::min();
                double routetime;
                int netsRouted = 0;
                
                for (unsigned int n = 0; n < numNets; n++) { //for each net
                    RouteNet& net = nets[n];
                    routetimer.restart();
                    //if (testReroute(nets[n].routeNodes())) {
                    if (true) {
                    
                        unrouteNet(net.routeNodes(), net.getName());
                        
                        try {
                            unmarkSourcesAndSinks(net);
                            mNetRouter->route(net);
                            markSourcesAndSinks(net);
                            updateSharing(net.routeNodes());
                        }
                        catch (...) {
                            std::cout << "Failed routing net " << net.getName() << " index: "
                                << n << " of " << nets.size() << std::endl;
                            throw;
                        }

                        routetime = routetimer.elapsed();

                        if (routetime < minroutetime)
                            minroutetime = routetime;
                        if (routetime > maxroutetime)
                            maxroutetime = routetime;
                        avgroutetime += routetime;
                        netsRouted++;
                    }
                }
                avgroutetime = avgroutetime / netsRouted;
                
                updatetimer.restart();
                PathFinderSharingMap::iterator p;
                unsigned int conflicts = 0;
                unsigned int maxpresent = 0;
                unsigned int maxhistory = 0;
                Tilewire maxPresentTilewire;
                Tilewire maxHistoryTilewire;
                for (p = mConflicts.begin(); p != mConflicts.end(); p++)
                {
                    if ((*p).second.mPresentSharing > 1)
                    {
                        (*p).second.mHistorySharing += (*p).second.mPresentSharing; 
                        conflicts++;
                    }
                    
                    if ((*p).second.mPresentSharing > maxpresent)
                    {
                        maxpresent = (*p).second.mPresentSharing;
                        maxPresentTilewire = (*p).first;
                    }
                    if ((*p).second.mHistorySharing > maxhistory)
                    {
                        maxhistory = (*p).second.mHistorySharing;
                        maxHistoryTilewire = (*p).first;
                    }
                }
                updatetime += updatetimer.elapsed();
                
//              std::cout << "Conflicts this iteration: " << conflicts << " max present: " 
//                  << maxpresent << " max history: " << maxhistory << std::endl;
//              std::cout << "Total conflict records: " << mConflicts.size() << std::endl;
//              std::cout << "Nets rerouted: " << netsRouted << "/" << numNets << std::endl;
//              std::cout << "Total time: " << totaltimer.elapsed() 
//                  << " iteration time: " << iterationtimer.elapsed() 
//                  << " average route time: " << avgroutetime
//                  << " total update time: " << updatetime
//                  << std::endl;
                    
                if (netsRouted == 1) {
                    flag_resources = false;
                    for (unsigned int i = 0; i < numNets; i++) {
                        RouteNet& net = nets[i];
                        if (testReroute(net.routeNodes())) {
                            std::cout << "FOUND SELF CONFLICT NET: " << net.getName() << std::endl;
                            std::cout << mDB;
                            for (unsigned int j = 0; j < net.routeNodes().size(); j++) {
                                std::cout << "\t" << net.routeNodes()[j]->getArc() << std::endl;
                            }
                        }
                    }
                }
                
//              std::cout << "Max Present Tilewire: " << maxPresentTilewire 
//                  << " Max History Tilewire: " << maxHistoryTilewire << std::endl;
                
                if (conflicts == 0) flag_resources = false;
                routingPasses++;
            } // end iteraton while loop
            std::cout << std::endl;
            std::cout << "Total time: " << totaltimer.elapsed() << " Update time: " << updatetime 
                << std::endl;
            
//          std::cout << "RECORD RESULT" << std::endl;
        } // end of function

        void unrouteNet(RouteNodePtrVector& routeVector, const string& netname)
        {
            int rVecSize = routeVector.size();
            for (int x = 0; x < rVecSize; x++)
            {
                mTempWireSources.clear();
                mDB.expandSegment(routeVector[x]->getSinkTilewire(), mTempWireSources);
                int numWireSources = mTempWireSources.size();
                for (int i = 0; i < numWireSources; i++)
                {
                    Tilewire tw = mTempWireSources[i];
                    if (mConflicts.find(tw) != mConflicts.end())
                    {
                        mConflicts[tw].mPresentSharing--;
                        if (mConflicts[tw].mPresentSharing == 0)
                        {
                            mConflictWireUsage.release(tw);
                        }
                        if (mConflicts[tw].mPresentSharing < 0)
                        {
                            std::cout << "ERROR PRESENT: " << tw << " net " << netname << std::endl;
                            throw;
                        }
                    }
                    else 
                    {
                        mConflictWireUsage.release(tw);
                    }
                }
                delete routeVector[x];
                deleteCount++;
            }
            routeVector.clear();
        }
        void updateSharing(RouteNodePtrVector& outRoute) {
            for (unsigned int i = 0; i < outRoute.size(); i++) {
                updateSharing(outRoute[i]->getSinkTilewire());
            }
        }
        void updateSharing(const Tilewire& inTilewire) {
            mTempWireSources.clear();
            mDB.expandSegment(inTilewire, mTempWireSources);
            int numWireSources = mTempWireSources.size();
            for (int i = 0; i < numWireSources; i++) {
                Tilewire tw = mTempWireSources[i];
                if (mConflictWireUsage.isUsed(tw)) {
                    if (mConflicts.find(tw) != mConflicts.end()) {
                        mConflicts[tw].mPresentSharing++;
                    } else {
                        mConflicts[tw].mPresentSharing = 2;
                        mConflicts[tw].mHistorySharing = 0;
                    }
                } else {
                    if (mConflicts.find(tw) != mConflicts.end()) {
                        mConflicts[tw].mPresentSharing++;
                    }
                    mConflictWireUsage.use(tw);
                }
            }
            
        }
        
        void recordResult(std::vector<RouteNodePtrVector>& outRoutes, 
            std::vector<RouteNodePtrVector>& tempRoutes, 
            std::vector<unsigned int>& priorities, unsigned int plevel) {
            if (outRoutes.size() != tempRoutes.size()) {
                std::cout << "BAD SIZE: " << outRoutes.size() << " " << tempRoutes.size() << std::endl;
                return;
            }
            for (unsigned int i = 0; i < outRoutes.size(); i++) {
                recordResult(outRoutes[i], tempRoutes[i]);
            }
        }
        void recordResult(RouteNodePtrVector& outRoute, RouteNodePtrVector& tempRoute) {
            Arc arc;
            for (unsigned int i = 0; i < tempRoute.size(); i++) {
                outRoute.push_back(tempRoute[i]);
                arc = tempRoute[i]->getArc();
                mDB.useArc(arc);
            }
        }
        
        bool testReroute(RouteNodePtrVector& currentRoute) {
            for (unsigned int i = 0; i < currentRoute.size(); i++) {
                if (mConflicts.find(currentRoute[i]->getSinkTilewire()) != mConflicts.end() 
                    && mConflicts[currentRoute[i]->getSinkTilewire()].mPresentSharing > 1) {
                    return true;
                }
            }
            return false;
        }
        
        void unmarkSourcesAndSinks(RouteNet& net) {
            mDB.releaseSegment(*net.sourcesBegin());
            RouteNet::TilewireConstIterator p;
            RouteNet::TilewireConstIterator e = net.sinksEnd();
            for (p = net.sinksBegin(); p != e; p++) {
                mDB.releaseSegment(*p);
            }
        }
        void markSourcesAndSinks(RouteNet& net)
        {
            mDB.useSegment(*net.sourcesBegin());
            RouteNet::TilewireConstIterator p;
            RouteNet::TilewireConstIterator e = net.sinksEnd();
            for (p = net.sinksBegin(); p != e; p++) {
                mDB.useSegment(*p);
            }
        }
        
    }; // class PathFinder
} // namespace router
} // namespace torc
#endif // TORC_ROUTER_PATHFINDER_HPP