mfsWin.c 3.67 KB
Newer Older
Alan Mishchenko committed
1 2 3 4 5 6 7 8
/**CFile****************************************************************

  FileName    [mfsWin.c]

  SystemName  [ABC: Logic synthesis and verification system.]

  PackageName [The good old minimization with complete don't-cares.]

Alan Mishchenko committed
9
  Synopsis    [Procedures to compute windows stretching to the PIs.]
Alan Mishchenko committed
10 11 12 13 14 15 16 17 18 19 20 21 22

  Author      [Alan Mishchenko]
  
  Affiliation [UC Berkeley]

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

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

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

#include "mfsInt.h"

23 24 25
ABC_NAMESPACE_IMPL_START


Alan Mishchenko committed
26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115
////////////////////////////////////////////////////////////////////////
///                        DECLARATIONS                              ///
////////////////////////////////////////////////////////////////////////

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

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

  Synopsis    [Returns 1 if the node should be a root.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
static inline int Abc_MfsComputeRootsCheck( Abc_Obj_t * pNode, int nLevelMax, int nFanoutLimit )
{
    Abc_Obj_t * pFanout;
    int i;
    // the node is the root if one of the following is true:
    // (1) the node has more than fanouts than the limit
    if ( Abc_ObjFanoutNum(pNode) > nFanoutLimit )
        return 1;
    // (2) the node has CO fanouts
    // (3) the node has fanouts above the cutoff level
    Abc_ObjForEachFanout( pNode, pFanout, i )
        if ( Abc_ObjIsCo(pFanout) || (int)pFanout->Level > nLevelMax )
            return 1;
    return 0;
}

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

  Synopsis    [Recursively collects the root candidates.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
void Abc_MfsComputeRoots_rec( Abc_Obj_t * pNode, int nLevelMax, int nFanoutLimit, Vec_Ptr_t * vRoots )
{
    Abc_Obj_t * pFanout;
    int i;
    assert( Abc_ObjIsNode(pNode) );
    if ( Abc_NodeIsTravIdCurrent(pNode) )
        return;
    Abc_NodeSetTravIdCurrent( pNode );
    // check if the node should be the root
    if ( Abc_MfsComputeRootsCheck( pNode, nLevelMax, nFanoutLimit ) )
        Vec_PtrPush( vRoots, pNode );
    else // if not, explore its fanouts
        Abc_ObjForEachFanout( pNode, pFanout, i )
            Abc_MfsComputeRoots_rec( pFanout, nLevelMax, nFanoutLimit, vRoots );
}

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

  Synopsis    [Recursively collects the root candidates.]

  Description [Returns 1 if the only root is this node.]
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
Vec_Ptr_t * Abc_MfsComputeRoots( Abc_Obj_t * pNode, int nWinTfoMax, int nFanoutLimit )
{
    Vec_Ptr_t * vRoots;
    vRoots = Vec_PtrAlloc( 10 );
    Abc_NtkIncrementTravId( pNode->pNtk );
    Abc_MfsComputeRoots_rec( pNode, pNode->Level + nWinTfoMax, nFanoutLimit, vRoots );
    assert( Vec_PtrSize(vRoots) > 0 );
//    if ( Vec_PtrSize(vRoots) == 1 && Vec_PtrEntry(vRoots, 0) == pNode )
//        return 0;
    return vRoots;
}

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


116 117
ABC_NAMESPACE_IMPL_END