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/**CFile****************************************************************

  FileName    [abcFraig.c]

  SystemName  [ABC: Logic synthesis and verification system.]

  PackageName [Network and node package.]

  Synopsis    [Procedures interfacing with the FRAIG package.]

  Author      [Alan Mishchenko]
  
  Affiliation [UC Berkeley]

  Date        [Ver. 1.0. Started - June 20, 2005.]

  Revision    [$Id: abcFraig.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]

***********************************************************************/

#include "abc.h"
#include "fraig.h"
#include "main.h"

////////////////////////////////////////////////////////////////////////
///                        DECLARATIONS                              ///
////////////////////////////////////////////////////////////////////////

extern Fraig_Man_t * Abc_NtkToFraig( Abc_Ntk_t * pNtk, Fraig_Params_t * pParams, int fAllNodes );
static Abc_Ntk_t *   Abc_NtkFromFraig( Fraig_Man_t * pMan, Abc_Ntk_t * pNtk );
static Abc_Obj_t *   Abc_NodeFromFraig_rec( Abc_Ntk_t * pNtkNew, Fraig_Node_t * pNodeFraig );

static int           Abc_NtkFraigTrustCheck( Abc_Ntk_t * pNtk );
static void          Abc_NtkFraigTrustOne( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkNew );
static Abc_Obj_t *   Abc_NodeFraigTrust( Abc_Aig_t * pMan, Abc_Obj_t * pNode );
 
////////////////////////////////////////////////////////////////////////
///                     FUNCTION DEFITIONS                           ///
////////////////////////////////////////////////////////////////////////

/**Function*************************************************************

  Synopsis    [Interfaces the network with the FRAIG package.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Abc_Ntk_t * Abc_NtkFraig( Abc_Ntk_t * pNtk, void * pParams, int fAllNodes )
{
    Fraig_Params_t * pPars = pParams;
    Abc_Ntk_t * pNtkNew;
    Fraig_Man_t * pMan;
    // perform fraiging
    pMan = Abc_NtkToFraig( pNtk, pParams, fAllNodes ); 
    // prove the miter if asked to
    if ( pPars->fTryProve )
        Fraig_ManProveMiter( pMan );
    // reconstruct FRAIG in the new network
    pNtkNew = Abc_NtkFromFraig( pMan, pNtk );
    Fraig_ManFree( pMan );
    // make sure that everything is okay
    if ( !Abc_NtkCheck( pNtkNew ) )
    {
        printf( "Abc_NtkFraig: The network check has failed.\n" );
        Abc_NtkDelete( pNtkNew );
        return NULL;
    }
    return pNtkNew;
}

/**Function*************************************************************

  Synopsis    [Transforms the strashed network into FRAIG.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Fraig_Man_t * Abc_NtkToFraig( Abc_Ntk_t * pNtk, Fraig_Params_t * pParams, int fAllNodes )
{
    Fraig_Man_t * pMan;
    ProgressBar * pProgress;
    Fraig_Node_t * pNodeFraig;
    Vec_Ptr_t * vNodes;
    Abc_Obj_t * pNode, * pConst1, * pReset;
    int i;

    assert( Abc_NtkIsStrash(pNtk) );

    // create the FRAIG manager
    pMan = Fraig_ManCreate( pParams );

    // create PIs and remember them in the old nodes
    Abc_NtkCleanCopy( pNtk );
    Abc_NtkForEachCi( pNtk, pNode, i )
        pNode->pCopy = (Abc_Obj_t *)Fraig_ManReadIthVar(pMan, i);
    pConst1 = Abc_AigConst1( pNtk->pManFunc );
    pReset  = Abc_AigReset( pNtk->pManFunc );

    // perform strashing
    vNodes = Abc_AigDfs( pNtk, fAllNodes, 0 );
    if ( !pParams->fInternal )
        pProgress = Extra_ProgressBarStart( stdout, vNodes->nSize );
    Vec_PtrForEachEntry( vNodes, pNode, i )
    {
        if ( !pParams->fInternal )
            Extra_ProgressBarUpdate( pProgress, i, NULL );
        if ( pNode == pConst1 )
            pNodeFraig = Fraig_ManReadConst1(pMan);
        else if ( pNode == pReset )
            continue;
        else
            pNodeFraig = Fraig_NodeAnd( pMan, 
                Fraig_NotCond( Abc_ObjFanin0(pNode)->pCopy, Abc_ObjFaninC0(pNode) ),
                Fraig_NotCond( Abc_ObjFanin1(pNode)->pCopy, Abc_ObjFaninC1(pNode) ) );
        assert( pNode->pCopy == NULL );
        pNode->pCopy = (Abc_Obj_t *)pNodeFraig;
    }
    if ( !pParams->fInternal )
        Extra_ProgressBarStop( pProgress );
    Vec_PtrFree( vNodes );

    // set the primary outputs
    Abc_NtkForEachCo( pNtk, pNode, i )
        Fraig_ManSetPo( pMan, (Fraig_Node_t *)Abc_ObjNotCond( Abc_ObjFanin0(pNode)->pCopy, Abc_ObjFaninC0(pNode) ) );
    return pMan;
}

/**Function*************************************************************

  Synopsis    [Transforms FRAIG into what looks like a strashed network.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Abc_Ntk_t * Abc_NtkFromFraig( Fraig_Man_t * pMan, Abc_Ntk_t * pNtk )
{
//    ProgressBar * pProgress;
    Abc_Ntk_t * pNtkNew;
    Abc_Obj_t * pNode, * pNodeNew;
    int i;
    // create the new network
    pNtkNew = Abc_NtkStartFrom( pNtk, ABC_TYPE_STRASH, ABC_FUNC_AIG );
    // make the mapper point to the new network
    Abc_NtkForEachCi( pNtk, pNode, i )
        Fraig_NodeSetData1( Fraig_ManReadIthVar(pMan, i), (Fraig_Node_t *)pNode->pCopy );
    // set the constant node
    Fraig_NodeSetData1( Fraig_ManReadConst1(pMan), (Fraig_Node_t *)Abc_AigConst1(pNtkNew->pManFunc) );
    // process the nodes in topological order
//    pProgress = Extra_ProgressBarStart( stdout, Abc_NtkCoNum(pNtk) );
    Abc_NtkForEachCo( pNtk, pNode, i )
    {
//        Extra_ProgressBarUpdate( pProgress, i, NULL );
        pNodeNew = Abc_NodeFromFraig_rec( pNtkNew, Fraig_ManReadOutputs(pMan)[i] );
        Abc_ObjAddFanin( pNode->pCopy, pNodeNew );
    }
//    Extra_ProgressBarStop( pProgress );
    return pNtkNew;
}

/**Function*************************************************************

  Synopsis    [Transforms into AIG one node.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Abc_Obj_t * Abc_NodeFromFraig_rec( Abc_Ntk_t * pNtkNew, Fraig_Node_t * pNodeFraig )
{
    Abc_Obj_t * pRes, * pRes0, * pRes1, * pResMin, * pResCur;
    Fraig_Node_t * pNodeTemp, * pNodeFraigR = Fraig_Regular(pNodeFraig);
    void ** ppTail;
    // check if the node was already considered
    if ( pRes = (Abc_Obj_t *)Fraig_NodeReadData1(pNodeFraigR) )
        return Abc_ObjNotCond( pRes, Fraig_IsComplement(pNodeFraig) );
    // solve the children
    pRes0 = Abc_NodeFromFraig_rec( pNtkNew, Fraig_NodeReadOne(pNodeFraigR) );
    pRes1 = Abc_NodeFromFraig_rec( pNtkNew, Fraig_NodeReadTwo(pNodeFraigR) );
    // derive the new node
    pRes = Abc_AigAnd( pNtkNew->pManFunc, pRes0, pRes1 );
    pRes->fPhase = Fraig_NodeReadSimInv( pNodeFraigR );
    // if the node has an equivalence class, find its representative
    if ( Fraig_NodeReadRepr(pNodeFraigR) == NULL && Fraig_NodeReadNextE(pNodeFraigR) != NULL )
    {
        // go through the FRAIG nodes belonging to this equivalence class
        // and find the representative node (the node with the smallest level)
        pResMin = pRes;
        for ( pNodeTemp = Fraig_NodeReadNextE(pNodeFraigR); pNodeTemp; pNodeTemp = Fraig_NodeReadNextE(pNodeTemp) )
        {
            assert( Fraig_NodeReadData1(pNodeTemp) == NULL );
            pResCur = Abc_NodeFromFraig_rec( pNtkNew, pNodeTemp );
            if ( pResMin->Level > pResCur->Level )
                pResMin = pResCur;
        }
        // link the nodes in such a way that representative goes first
        ppTail = &pResMin->pData;
        if ( pRes != pResMin )
        {
            *ppTail = pRes;
            ppTail = &pRes->pData;
        }
        for ( pNodeTemp = Fraig_NodeReadNextE(pNodeFraigR); pNodeTemp; pNodeTemp = Fraig_NodeReadNextE(pNodeTemp) )
        {
            pResCur = (Abc_Obj_t *)Fraig_NodeReadData1(pNodeTemp);
            assert( pResCur );
            if ( pResMin == pResCur )
                continue;
            *ppTail = pResCur;
            ppTail = &pResCur->pData;
        }
        assert( *ppTail == NULL );

        // update the phase of the node
        pRes = Abc_ObjNotCond( pResMin, (pRes->fPhase ^ pResMin->fPhase) );
    }
    Fraig_NodeSetData1( pNodeFraigR, (Fraig_Node_t *)pRes );
    return Abc_ObjNotCond( pRes, Fraig_IsComplement(pNodeFraig) );
}




/**Function*************************************************************

  Synopsis    [Interfaces the network with the FRAIG package.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Abc_Ntk_t * Abc_NtkFraigTrust( Abc_Ntk_t * pNtk )
{
    Abc_Ntk_t * pNtkNew;

    if ( !Abc_NtkIsSopLogic(pNtk) )
    {
        printf( "Abc_NtkFraigTrust: Trust mode works for netlists and logic SOP networks.\n" );
        return NULL;
    }

    if ( !Abc_NtkFraigTrustCheck(pNtk) )
    {
        printf( "Abc_NtkFraigTrust: The network does not look like an AIG with choice nodes.\n" );
        return NULL;
    }
    
    // perform strashing
    pNtkNew = Abc_NtkStartFrom( pNtk, ABC_TYPE_STRASH, ABC_FUNC_AIG );
    Abc_NtkFraigTrustOne( pNtk, pNtkNew );
    Abc_NtkFinalize( pNtk, pNtkNew );

    // print a warning about choice nodes
    printf( "Warning: The resulting AIG contains %d choice nodes.\n", Abc_NtkGetChoiceNum( pNtkNew ) );

    // make sure that everything is okay
    if ( !Abc_NtkCheck( pNtkNew ) )
    {
        printf( "Abc_NtkFraigTrust: The network check has failed.\n" );
        Abc_NtkDelete( pNtkNew );
        return NULL;
    }
    return pNtkNew;
}

/**Function*************************************************************

  Synopsis    [Checks whether the node can be processed in the trust mode.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
int Abc_NtkFraigTrustCheck( Abc_Ntk_t * pNtk )
{
    Abc_Obj_t * pNode;
    int i, nFanins;
    Abc_NtkForEachNode( pNtk, pNode, i )
    {
        nFanins = Abc_ObjFaninNum(pNode);
        if ( nFanins < 2 )
            continue;
        if ( nFanins == 2 && Abc_SopIsAndType(pNode->pData) )
            continue;
        if ( !Abc_SopIsOrType(pNode->pData) )
            return 0;
    }
    return 1;
}

/**Function*************************************************************

  Synopsis    [Interfaces the network with the FRAIG package.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Abc_NtkFraigTrustOne( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkNew )
{
    ProgressBar * pProgress;
    Abc_Aig_t * pMan = pNtkNew->pManFunc;
    Vec_Ptr_t * vNodes;
    Abc_Obj_t * pNode, * pNodeNew, * pObj;
    int i;

    // perform strashing
    vNodes = Abc_NtkDfs( pNtk, 0 );
    pProgress = Extra_ProgressBarStart( stdout, vNodes->nSize );
    Vec_PtrForEachEntry( vNodes, pNode, i )
    {
        Extra_ProgressBarUpdate( pProgress, i, NULL );
        // get the node
        assert( Abc_ObjIsNode(pNode) );
         // strash the node
        pNodeNew = Abc_NodeFraigTrust( pMan, pNode );
        // get the old object
        if ( Abc_NtkIsNetlist(pNtk) )
            pObj = Abc_ObjFanout0( pNode ); // the fanout net 
        else 
            pObj = pNode; // the node itself
        // make sure the node is not yet strashed
        assert( pObj->pCopy == NULL );
        // mark the old object with the new AIG node
        pObj->pCopy = pNodeNew;
    }
    Vec_PtrFree( vNodes );
    Extra_ProgressBarStop( pProgress );
}

/**Function*************************************************************

  Synopsis    [Transforms one node into a FRAIG in the trust mode.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Abc_Obj_t * Abc_NodeFraigTrust( Abc_Aig_t * pMan, Abc_Obj_t * pNode )
{
    Abc_Obj_t * pSum, * pFanin;
    Abc_Obj_t * pConst1 = Abc_AigConst1(pMan);
    void ** ppTail;
    int i, nFanins, fCompl;

    assert( Abc_ObjIsNode(pNode) );
    // get the number of node's fanins
    nFanins = Abc_ObjFaninNum( pNode );
    assert( nFanins == Abc_SopGetVarNum(pNode->pData) );
    // check if it is a constant
    if ( nFanins == 0 )
        return Abc_ObjNotCond( pConst1, Abc_SopIsConst0(pNode->pData) );
    if ( nFanins == 1 )
        return Abc_ObjNotCond( Abc_ObjFanin0(pNode)->pCopy, Abc_SopIsInv(pNode->pData) );
    if ( nFanins == 2 && Abc_SopIsAndType(pNode->pData) )
        return Abc_AigAnd( pMan, 
            Abc_ObjNotCond( Abc_ObjFanin0(pNode)->pCopy, !Abc_SopGetIthCareLit(pNode->pData,0) ),
            Abc_ObjNotCond( Abc_ObjFanin1(pNode)->pCopy, !Abc_SopGetIthCareLit(pNode->pData,1) )  );
    assert( Abc_SopIsOrType(pNode->pData) );
    fCompl = Abc_SopGetIthCareLit(pNode->pData,0);
    // get the root of the choice node (the first fanin)
    pSum = Abc_ObjFanin0(pNode)->pCopy;
    // connect other fanins
    ppTail = &pSum->pData;
    Abc_ObjForEachFanin( pNode, pFanin, i )
    {
        if ( i == 0 )
            continue;
        *ppTail = pFanin->pCopy;
        ppTail = &pFanin->pCopy->pData;
        // set the complemented bit of this cut
        if ( fCompl ^ Abc_SopGetIthCareLit(pNode->pData, i) )
            pFanin->pCopy->fPhase = 1;
    }
    assert( *ppTail == NULL );
    return pSum;
}




/**Function*************************************************************

  Synopsis    [Interfaces the network with the FRAIG package.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
int Abc_NtkFraigStore( Abc_Ntk_t * pNtk )
{
    extern int Abc_NtkAppendNew( Abc_Ntk_t * pNtk1, Abc_Ntk_t * pNtk2 );

    Abc_Ntk_t * pStore;
    int nAndsOld;

    if ( !Abc_NtkIsLogic(pNtk) && !Abc_NtkIsStrash(pNtk) )
    {
        printf( "The netlist need to be converted into a logic network before adding it to storage.\n" );
        return 0;
    }

    // get the network currently stored
    pStore = Abc_FrameReadNtkStore();
    if ( pStore == NULL )
    {
        // start the stored network
        pStore = Abc_NtkStrash( pNtk, 0, 0 );
        if ( pStore == NULL )
        {
            printf( "Abc_NtkFraigStore: Initial strashing has failed.\n" );
            return 0;
        }
        // save the parameters
        Abc_FrameSetNtkStore( pStore );
        Abc_FrameSetNtkStoreSize( 1 );
        nAndsOld = 0;
    }
    else
    {
        // add the new network to storage
        nAndsOld = Abc_NtkNodeNum( pStore );
//        if ( !Abc_NtkAppend( pStore, pNtk ) )
        if ( !Abc_NtkAppendNew( pStore, pNtk ) )
        {
            printf( "The current network cannot be appended to the stored network.\n" );
            return 0;
        }
        // set the number of networks stored
        Abc_FrameSetNtkStoreSize( Abc_FrameReadNtkStoreSize() + 1 );
    }
    printf( "The number of AIG nodes added to storage = %5d.\n", Abc_NtkNodeNum(pStore) - nAndsOld );
    return 1;
}

/**Function*************************************************************

  Synopsis    [Interfaces the network with the FRAIG package.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Abc_Ntk_t * Abc_NtkFraigRestore()
{
    extern Abc_Ntk_t * Abc_NtkFraigPartitioned( Abc_Ntk_t * pNtk, void * pParams );

    Fraig_Params_t Params;
    Abc_Ntk_t * pStore, * pFraig;
    int nWords1, nWords2, nWordsMin;
    int clk = clock();

    // get the stored network
    pStore = Abc_FrameReadNtkStore();
    Abc_FrameSetNtkStore( NULL );
    if ( pStore == NULL )
    {
        printf( "There are no network currently in storage.\n" );
        return NULL;
    }
    printf( "Currently stored %d networks with %d nodes will be fraiged.\n", 
        Abc_FrameReadNtkStoreSize(), Abc_NtkNodeNum(pStore) );

    // to determine the number of simulation patterns
    // use the following strategy
    // at least 64 words (32 words random and 32 words dynamic)
    // no more than 256M for one circuit (128M + 128M)
    nWords1 = 32;
    nWords2 = (1<<27) / (Abc_NtkNodeNum(pStore) + Abc_NtkCiNum(pStore));
    nWordsMin = ABC_MIN( nWords1, nWords2 );

    // set parameters for fraiging
    Fraig_ParamsSetDefault( &Params );
    Params.nPatsRand  = nWordsMin * 32; // the number of words of random simulation info
    Params.nPatsDyna  = nWordsMin * 32; // the number of words of dynamic simulation info
//    Params.nBTLimit   = 99;             // the max number of backtracks to perform
    Params.nBTLimit   = 1000000;             // the max number of backtracks to perform
    Params.fFuncRed   =  1;             // performs only one level hashing
    Params.fFeedBack  =  1;             // enables solver feedback
    Params.fDist1Pats =  1;             // enables distance-1 patterns
    Params.fDoSparse  =  1;             // performs equiv tests for sparse functions 
    Params.fChoicing  =  1;             // enables recording structural choices
    Params.fTryProve  =  0;             // tries to solve the final miter
    Params.fVerbose   =  0;             // the verbosiness flag
    Params.fInternal  =  1;             // the flag indicates the internal run 

//    Fraig_ManReportChoices( p );
    // transform it into FRAIG
//    pFraig = Abc_NtkFraig( pStore, &Params, 1 );
    pFraig = Abc_NtkFraigPartitioned( pStore, &Params );

PRT( "Total fraiging time", clock() - clk );
    if ( pFraig == NULL )
        return NULL;
    Abc_NtkDelete( pStore );
    return pFraig;
}

/**Function*************************************************************

  Synopsis    [Interfaces the network with the FRAIG package.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Abc_NtkFraigStoreClean()
{
    Abc_Ntk_t * pStore;
    // get the stored network
    pStore = Abc_FrameReadNtkStore();
    if ( pStore )
        Abc_NtkDelete( pStore );
    Abc_FrameSetNtkStore( NULL );
}

/**Function*************************************************************

  Synopsis    [Checks the correctness of stored networks.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Abc_NtkFraigStoreCheck( Abc_Ntk_t * pFraig )
{
    Abc_Obj_t * pNode0, * pNode1;
    int nPoOrig, nPoFinal, nStored; 
    int i, k;
    // check that the PO functions are correct
    nPoFinal = Abc_NtkPoNum(pFraig);
    nStored  = Abc_FrameReadNtkStoreSize(Abc_FrameGetGlobalFrame());
    assert( nPoFinal % nStored == 0 );
    nPoOrig  = nPoFinal / nStored;
    for ( i = 0; i < nPoOrig; i++ )
    {
        pNode0 = Abc_ObjFanin0( Abc_NtkPo(pFraig, i) ); 
        for ( k = 1; k < nStored; k++ )
        {
            pNode1 = Abc_ObjFanin0( Abc_NtkPo(pFraig, k*nPoOrig+i) ); 
            if ( pNode0 != pNode1 )
                printf( "Verification for PO #%d of network #%d has failed. The PO function is not used.\n", i+1, k+1 );
        }
    }
}

////////////////////////////////////////////////////////////////////////
///                       END OF FILE                                ///
////////////////////////////////////////////////////////////////////////