/**Function*************************************************************
Synopsis [Collects used internal nodes in a topological order.]
Description [Additionally considers objects in groups as a single object
and collects them in a topological order together as single entity.]
SideEffects []
SeeAlso []
***********************************************************************/
void Sfm_NtkDfs_rec( Sfm_Ntk_t * p, int iNode, Vec_Int_t * vNodes, Vec_Wec_t * vGroups, Vec_Int_t * vGroupMap, Vec_Int_t * vBoxesLeft )
{
int i, iFanin;
if ( Sfm_ObjIsPi(p, iNode) )
return;
if ( Sfm_ObjIsTravIdCurrent(p, iNode) )
return;
if ( Vec_IntEntry(vGroupMap, iNode) >= 0 )
{
int k, iGroup = Abc_Lit2Var( Vec_IntEntry(vGroupMap, iNode) );
Vec_Int_t * vGroup = Vec_WecEntry( vGroups, iGroup );
Vec_IntForEachEntry( vGroup, iNode, i )
assert( Sfm_ObjIsNode(p, iNode) );
Vec_IntForEachEntry( vGroup, iNode, i )
Sfm_ObjSetTravIdCurrent( p, iNode );
Vec_IntForEachEntry( vGroup, iNode, i )
Sfm_ObjForEachFanin( p, iNode, iFanin, k )
Sfm_NtkDfs_rec( p, iFanin, vNodes, vGroups, vGroupMap, vBoxesLeft );
Vec_IntForEachEntry( vGroup, iNode, i )
Vec_IntPush( vNodes, iNode );
Vec_IntPush( vBoxesLeft, iGroup );
}
else
{
Sfm_ObjSetTravIdCurrent(p, iNode);
Sfm_ObjForEachFanin( p, iNode, iFanin, i )
Sfm_NtkDfs_rec( p, iFanin, vNodes, vGroups, vGroupMap, vBoxesLeft );
Vec_IntPush( vNodes, iNode );
}
}
int Sfm_ObjMffcSize( Sfm_Ntk_t * p, int iObj )
{
int Count1, Count2;
if ( Sfm_ObjIsPi(p, iObj) )
return 0;
if ( Sfm_ObjFanoutNum(p, iObj) != 1 )
return 0;
assert( Sfm_ObjIsNode( p, iObj ) );
Count1 = Sfm_ObjDeref( p, iObj );
Count2 = Sfm_ObjRef( p, iObj );
assert( Count1 == Count2 );
return Count1;
}
int Sfm_NodeResub( Sfm_Ntk_t * p, int iNode )
{
int i, iFanin;
p->nNodesTried++;
// prepare SAT solver
if ( !Sfm_NtkCreateWindow( p, iNode, p->pPars->fVeryVerbose ) )
return 0;
if ( !Sfm_NtkWindowToSolver( p ) )
return 0;
// try replacing area critical fanins
Sfm_ObjForEachFanin( p, iNode, iFanin, i )
if ( Sfm_ObjIsNode(p, iFanin) && Sfm_ObjFanoutNum(p, iFanin) == 1 )
{
if ( Sfm_NodeResubSolve( p, iNode, i, 0 ) )
return 1;
}
if ( p->pPars->fArea )
return 0;
// try removing redundant edges
Sfm_ObjForEachFanin( p, iNode, iFanin, i )
if ( !(Sfm_ObjIsNode(p, iFanin) && Sfm_ObjFanoutNum(p, iFanin) == 1) )
{
if ( Sfm_NodeResubSolve( p, iNode, i, 1 ) )
return 1;
}
/*
// try replacing area critical fanins while adding two new fanins
if ( Sfm_ObjFaninNum(p, iNode) < p->nFaninMax )
Abc_ObjForEachFanin( pNode, pFanin, i )
if ( !Abc_ObjIsCi(pFanin) && Abc_ObjFanoutNum(pFanin) == 1 )
{
if ( Abc_NtkMfsSolveSatResub2( p, pNode, i, -1 ) )
return 1;
}
*/
return 0;
}
int Sfm_ObjDeref_rec( Sfm_Ntk_t * p, int iObj )
{
int i, iFanin, Value, Count;
if ( Sfm_ObjIsPi(p, iObj) )
return 0;
assert( Sfm_ObjIsNode(p, iObj) );
Value = Sfm_ObjRefDecrement(p, iObj);
if ( Value > 0 )
return 0;
assert( Value == 0 );
Count = 1;
Sfm_ObjForEachFanin( p, iObj, iFanin, i )
Count += Sfm_ObjDeref_rec( p, iFanin );
return Count;
}
void Sfm_NtkComputeRoots_rec( Sfm_Ntk_t * p, int iNode, int nLevelMax, Vec_Int_t * vRoots, Vec_Int_t * vTfo )
{
int i, iFanout;
assert( Sfm_ObjIsNode(p, iNode) );
if ( Sfm_ObjIsTravIdCurrent(p, iNode) )
return;
Sfm_ObjSetTravIdCurrent(p, iNode);
if ( iNode != p->iPivotNode )
Vec_IntPush( vTfo, iNode );
// check if the node should be the root
if ( Sfm_NtkCheckRoot( p, iNode, nLevelMax ) )
Vec_IntPush( vRoots, iNode );
else // if not, explore its fanouts
Sfm_ObjForEachFanout( p, iNode, iFanout, i )
Sfm_NtkComputeRoots_rec( p, iFanout, nLevelMax, vRoots, vTfo );
}
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Returns the MFFC size.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Sfm_ObjRef_rec( Sfm_Ntk_t * p, int iObj )
{
int i, iFanin, Value, Count;
if ( Sfm_ObjIsPi(p, iObj) )
return 0;
assert( Sfm_ObjIsNode(p, iObj) );
Value = Sfm_ObjRefIncrement(p, iObj);
if ( Value > 1 )
return 0;
assert( Value == 1 );
Count = 1;
Sfm_ObjForEachFanin( p, iObj, iFanin, i )
Count += Sfm_ObjRef_rec( p, iFanin );
return Count;
}
int Sfm_NtkCreateWindow( Sfm_Ntk_t * p, int iNode, int fVerbose )
{
int i, k, iTemp;
abctime clkDiv, clkWin = Abc_Clock();
assert( Sfm_ObjIsNode( p, iNode ) );
p->iPivotNode = iNode;
Vec_IntClear( p->vNodes ); // internal
Vec_IntClear( p->vDivs ); // divisors
Vec_IntClear( p->vRoots ); // roots
Vec_IntClear( p->vTfo ); // roots
Vec_IntClear( p->vOrder ); // variable order
// collect transitive fanin
Sfm_NtkIncrementTravId( p );
if ( Sfm_NtkCollectTfi_rec( p, iNode, p->vNodes ) )
{
p->nMaxDivs++;
p->timeWin += Abc_Clock() - clkWin;
return 0;
}
// create divisors
clkDiv = Abc_Clock();
Vec_IntClear( p->vDivs );
Vec_IntAppend( p->vDivs, p->vNodes );
Vec_IntPop( p->vDivs );
// add non-topological divisors
if ( Vec_IntSize(p->vDivs) < p->pPars->nWinSizeMax + 0 )
{
Sfm_NtkIncrementTravId2( p );
Vec_IntForEachEntry( p->vDivs, iTemp, i )
if ( Vec_IntSize(p->vDivs) < p->pPars->nWinSizeMax + 0 )
// Sfm_NtkAddDivisors( p, iTemp, Sfm_ObjLevel(p, iNode) - 1 );
Sfm_NtkAddDivisors( p, iTemp, p->nLevelMax - Sfm_ObjLevelR(p, iNode) );
}
/**Function*************************************************************
Synopsis [Performs resubstitution for the node.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Sfm_NodeResubSolve( Sfm_Ntk_t * p, int iNode, int f, int fRemoveOnly )
{
int fSkipUpdate = 0;
int fVeryVerbose = 0;//p->pPars->fVeryVerbose && Vec_IntSize(p->vDivs) < 200;// || pNode->Id == 556;
int i, iFanin, iVar = -1;
word uTruth, uSign, uMask;
abctime clk;
assert( Sfm_ObjIsNode(p, iNode) );
assert( f >= 0 && f < Sfm_ObjFaninNum(p, iNode) );
p->nTryRemoves++;
// report init stats
if ( p->pPars->fVeryVerbose )
printf( "%5d : Lev =%3d. Leaf =%3d. Node =%3d. Div=%3d. Fanin =%4d (%d/%d). MFFC = %d\n",
iNode, Sfm_ObjLevel(p, iNode), 0, Vec_IntSize(p->vNodes), Vec_IntSize(p->vDivs),
Sfm_ObjFanin(p, iNode, f), f, Sfm_ObjFaninNum(p, iNode), Sfm_ObjMffcSize(p, Sfm_ObjFanin(p, iNode, f)) );
// clean simulation info
p->nCexes = 0;
Vec_WrdFill( p->vDivCexes, Vec_IntSize(p->vDivs), 0 );
// try removing the critical fanin
Vec_IntClear( p->vDivIds );
Sfm_ObjForEachFanin( p, iNode, iFanin, i )
if ( i != f )
Vec_IntPush( p->vDivIds, Sfm_ObjSatVar(p, iFanin) );
clk = Abc_Clock();
uTruth = Sfm_ComputeInterpolant( p );
p->timeSat += Abc_Clock() - clk;
// analyze outcomes
if ( uTruth == SFM_SAT_UNDEC )
{
p->nTimeOuts++;
return 0;
}
if ( uTruth != SFM_SAT_SAT )
goto finish;
if ( fRemoveOnly || p->pPars->fRrOnly || Vec_IntSize(p->vDivs) == 0 )
return 0;
p->nTryResubs++;
if ( fVeryVerbose )
{
for ( i = 0; i < 9; i++ )
printf( " " );
for ( i = 0; i < Vec_IntSize(p->vDivs); i++ )
printf( "%d", i % 10 );
printf( "\n" );
}
while ( 1 )
{
if ( fVeryVerbose )
{
printf( "%3d: %3d ", p->nCexes, iVar );
Vec_WrdForEachEntry( p->vDivCexes, uSign, i )
printf( "%d", Abc_InfoHasBit((unsigned *)&uSign, p->nCexes-1) );
printf( "\n" );
}
// find the next divisor to try
uMask = (~(word)0) >> (64 - p->nCexes);
Vec_WrdForEachEntry( p->vDivCexes, uSign, iVar )
if ( uSign == uMask )
break;
if ( iVar == Vec_IntSize(p->vDivs) )
return 0;
// try replacing the critical fanin
Vec_IntPush( p->vDivIds, Sfm_ObjSatVar(p, Vec_IntEntry(p->vDivs, iVar)) );
clk = Abc_Clock();
uTruth = Sfm_ComputeInterpolant( p );
p->timeSat += Abc_Clock() - clk;
// analyze outcomes
if ( uTruth == SFM_SAT_UNDEC )
{
p->nTimeOuts++;
return 0;
}
if ( uTruth != SFM_SAT_SAT )
goto finish;
if ( p->nCexes == 64 )
return 0;
// remove the last variable
Vec_IntPop( p->vDivIds );
}
finish:
if ( p->pPars->fVeryVerbose )
{
if ( iVar == -1 )
printf( "Node %d: Fanin %d (%d) can be removed. ", iNode, f, Sfm_ObjFanin(p, iNode, f) );
else
printf( "Node %d: Fanin %d (%d) can be replaced by divisor %d (%d). ",
iNode, f, Sfm_ObjFanin(p, iNode, f), iVar, Vec_IntEntry(p->vDivs, iVar) );
Kit_DsdPrintFromTruth( (unsigned *)&uTruth, Vec_IntSize(p->vDivIds) ); printf( "\n" );
}
if ( iVar == -1 )
p->nRemoves++;
else
p->nResubs++;
if ( fSkipUpdate )
return 0;
// update the network
Sfm_NtkUpdate( p, iNode, f, (iVar == -1 ? iVar : Vec_IntEntry(p->vDivs, iVar)), uTruth );
return 1;
}
