saigDual.c

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

  FileName    [saigDual.c]

  SystemName  [ABC: Logic synthesis and verification system.]

  PackageName [Sequential AIG package.]

  Synopsis    [Various duplication procedures.]

  Author      [Alan Mishchenko]
  
  Affiliation [UC Berkeley]

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

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

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

#include "saig.h"

ABC_NAMESPACE_IMPL_START


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

static inline void        Saig_ObjSetDual( Vec_Ptr_t * vCopies, int Id, int fPos, Aig_Obj_t * pItem ) { Vec_PtrWriteEntry( vCopies, 2*Id+fPos, pItem );         }
static inline Aig_Obj_t * Saig_ObjDual( Vec_Ptr_t * vCopies, int Id, int fPos )                       { return (Aig_Obj_t *)Vec_PtrEntry( vCopies, 2*Id+fPos ); }

static inline void        Saig_ObjDualFanin( Aig_Man_t * pAigNew, Vec_Ptr_t * vCopies, Aig_Obj_t * pObj, int iFanin, Aig_Obj_t ** ppRes0, Aig_Obj_t ** ppRes1 ) {

    Aig_Obj_t * pTemp0, * pTemp1, * pCare;
    int fCompl;
    assert( iFanin == 0 || iFanin == 1 );
    if ( iFanin == 0 )
    {
        pTemp0 = Saig_ObjDual( vCopies, Aig_ObjFaninId0(pObj), 0 );
        pTemp1 = Saig_ObjDual( vCopies, Aig_ObjFaninId0(pObj), 1 );
        fCompl = Aig_ObjFaninC0( pObj );
    }
    else
    {
        pTemp0 = Saig_ObjDual( vCopies, Aig_ObjFaninId1(pObj), 0 );
        pTemp1 = Saig_ObjDual( vCopies, Aig_ObjFaninId1(pObj), 1 );
        fCompl = Aig_ObjFaninC1( pObj );
    }
    if ( fCompl )
    {
        pCare   = Aig_Or( pAigNew, pTemp0, pTemp1 );
        *ppRes0 = Aig_And( pAigNew, pTemp1, pCare );
        *ppRes1 = Aig_And( pAigNew, pTemp0, pCare );
    }
    else
    {
        *ppRes0 = pTemp0;
        *ppRes1 = pTemp1;
    }
}

////////////////////////////////////////////////////////////////////////
///                     FUNCTION DEFINITIONS                         ///
////////////////////////////////////////////////////////////////////////

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

  Synopsis    [Transforms sequential AIG into dual-rail miter.]

  Description [Transforms sequential AIG into a miter encoding ternary
  problem formulated as follows "none of the POs has a ternary value".
  Interprets the first nDualPis as having ternary value.  Sets flops
  to have ternary intial value when fDualFfs is set to 1.]
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Aig_Man_t * Saig_ManDupDual( Aig_Man_t * pAig, int nDualPis, int fDualFfs, int fMiterFfs, int fComplPo )
{
    Vec_Ptr_t * vCopies;
    Aig_Man_t * pAigNew;
    Aig_Obj_t * pObj, * pTemp0, * pTemp1, * pTemp2, * pTemp3, * pCare, * pMiter;
    int i;
    assert( Saig_ManPoNum(pAig) > 0 );
    assert( nDualPis >= 0 && nDualPis <= Saig_ManPiNum(pAig) );
    vCopies = Vec_PtrStart( 2*Aig_ManObjNum(pAig) );
    // start the new manager
    pAigNew = Aig_ManStart( Aig_ManNodeNum(pAig) );
    pAigNew->pName = Abc_UtilStrsav( pAig->pName );
    // map the constant node
    Saig_ObjSetDual( vCopies, 0, 0, Aig_ManConst0(pAigNew) );
    Saig_ObjSetDual( vCopies, 0, 1, Aig_ManConst1(pAigNew) );
    // create variables for PIs
    Aig_ManForEachCi( pAig, pObj, i )
    {
        if ( i < nDualPis )
        {
            pTemp0 = Aig_ObjCreateCi( pAigNew );
            pTemp1 = Aig_ObjCreateCi( pAigNew );
        }
        else if ( i < Saig_ManPiNum(pAig) )
        {
            pTemp1 = Aig_ObjCreateCi( pAigNew );
            pTemp0 = Aig_Not( pTemp1 );
        }
        else
        {
            pTemp0 = Aig_ObjCreateCi( pAigNew );
            pTemp1 = Aig_ObjCreateCi( pAigNew );
            pTemp0 = Aig_NotCond( pTemp0, !fDualFfs );
        }
        Saig_ObjSetDual( vCopies, Aig_ObjId(pObj), 0, Aig_And(pAigNew, pTemp0, Aig_Not(pTemp1)) );
        Saig_ObjSetDual( vCopies, Aig_ObjId(pObj), 1, Aig_And(pAigNew, pTemp1, Aig_Not(pTemp0)) );
    }
    // create internal nodes
    Aig_ManForEachNode( pAig, pObj, i )
    {
        Saig_ObjDualFanin( pAigNew, vCopies, pObj, 0, &pTemp0, &pTemp1 );
        Saig_ObjDualFanin( pAigNew, vCopies, pObj, 1, &pTemp2, &pTemp3 );
        Saig_ObjSetDual( vCopies, Aig_ObjId(pObj), 0, Aig_Or (pAigNew, pTemp0, pTemp2) );
        Saig_ObjSetDual( vCopies, Aig_ObjId(pObj), 1, Aig_And(pAigNew, pTemp1, pTemp3) );
    }
    // create miter and flops
    pMiter = Aig_ManConst0(pAigNew);
    if ( fMiterFfs )
    {
        Saig_ManForEachLi( pAig, pObj, i )
        {
            Saig_ObjDualFanin( pAigNew, vCopies, pObj, 0, &pTemp0, &pTemp1 );
            pCare  = Aig_Or( pAigNew, pTemp0, pTemp1 );
            pMiter = Aig_Or( pAigNew, pMiter, Aig_Not(pCare) );
        }
    }
    else
    {
        Saig_ManForEachPo( pAig, pObj, i )
        {
            Saig_ObjDualFanin( pAigNew, vCopies, pObj, 0, &pTemp0, &pTemp1 );
            pCare  = Aig_Or( pAigNew, pTemp0, pTemp1 );
            pMiter = Aig_Or( pAigNew, pMiter, Aig_Not(pCare) );
        }
    }
    // create PO
    pMiter = Aig_NotCond( pMiter, fComplPo );
    Aig_ObjCreateCo( pAigNew, pMiter );
    // create flops
    Saig_ManForEachLi( pAig, pObj, i )
    {
        Saig_ObjDualFanin( pAigNew, vCopies, pObj, 0, &pTemp0, &pTemp1 );
        pTemp0 = Aig_NotCond( pTemp0, !fDualFfs );
        Aig_ObjCreateCo( pAigNew, pTemp0 );
        Aig_ObjCreateCo( pAigNew, pTemp1 );
    }
    // set the flops
    Aig_ManSetRegNum( pAigNew, 2 * Aig_ManRegNum(pAig) );
    Aig_ManCleanup( pAigNew );
    Vec_PtrFree( vCopies );
    return pAigNew;
}

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

  Synopsis    [Transforms sequential AIG to block the PO for N cycles.]

  Description [This procedure should be applied to a safety property 
  miter to make the propetry 'true' (const 0) during the first N cycles.]
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Saig_ManBlockPo( Aig_Man_t * pAig, int nCycles )
{
    Aig_Obj_t * pObj, * pCond, * pPrev;
    int i;
    assert( nCycles > 0 );
    // add N flops (assuming 1-hot encoding of cycles)
    pPrev = Aig_ManConst1(pAig);
    pCond = Aig_ManConst1(pAig);
    for ( i = 0; i < nCycles; i++ )
    {
        Aig_ObjCreateCo( pAig, pPrev );
        pPrev = Aig_ObjCreateCi( pAig );
        pCond = Aig_And( pAig, pCond, pPrev );
    }
    // update the POs
    Saig_ManForEachPo( pAig, pObj, i )
    {
        pCond = Aig_And( pAig, Aig_ObjChild0(pObj), pCond );
        Aig_ObjPatchFanin0( pAig, pObj, pCond );
    }
    // set the flops
    Aig_ManSetRegNum( pAig, Aig_ManRegNum(pAig) + nCycles );
}

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


ABC_NAMESPACE_IMPL_END