/**Function*************************************************************
Synopsis [Replaces node with a buffer fanin by a node without them.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Aig_NodeFixBufferFanins( Aig_Man_t * p, Aig_Obj_t * pObj, int fNodesOnly, int fUpdateLevel )
{
Aig_Obj_t * pFanReal0, * pFanReal1, * pResult;
p->nBufFixes++;
if ( Aig_ObjIsPo(pObj) )
{
assert( Aig_ObjIsBuf(Aig_ObjFanin0(pObj)) );
pFanReal0 = Aig_ObjReal_rec( Aig_ObjChild0(pObj) );
assert( Aig_ObjPhaseReal(Aig_ObjChild0(pObj)) == Aig_ObjPhaseReal(pFanReal0) );
Aig_ObjPatchFanin0( p, pObj, pFanReal0 );
return;
}
assert( Aig_ObjIsNode(pObj) );
assert( Aig_ObjIsBuf(Aig_ObjFanin0(pObj)) || Aig_ObjIsBuf(Aig_ObjFanin1(pObj)) );
// get the real fanins
pFanReal0 = Aig_ObjReal_rec( Aig_ObjChild0(pObj) );
pFanReal1 = Aig_ObjReal_rec( Aig_ObjChild1(pObj) );
// get the new node
if ( Aig_ObjIsNode(pObj) )
pResult = Aig_Oper( p, pFanReal0, pFanReal1, Aig_ObjType(pObj) );
// else if ( Aig_ObjIsLatch(pObj) )
// pResult = Aig_Latch( p, pFanReal0, Aig_ObjInit(pObj) );
else
assert( 0 );
// replace the node with buffer by the node without buffer
Aig_ObjReplace( p, pObj, pResult, fNodesOnly, fUpdateLevel );
}
/**Function*************************************************************
Synopsis [Replaces one object by another.]
Description [The new object (pObjNew) should be used instead of the old
object (pObjOld). If the new object is complemented or used, the buffer
is added and the new object remains in the manager; otherwise, the new
object is deleted.]
SideEffects []
SeeAlso []
***********************************************************************/
void Aig_ObjReplace( Aig_Man_t * p, Aig_Obj_t * pObjOld, Aig_Obj_t * pObjNew, int fNodesOnly, int fUpdateLevel )
{
Aig_Obj_t * pObjNewR = Aig_Regular(pObjNew);
// the object to be replaced cannot be complemented
assert( !Aig_IsComplement(pObjOld) );
// the object to be replaced cannot be a terminal
assert( !Aig_ObjIsPi(pObjOld) && !Aig_ObjIsPo(pObjOld) );
// the object to be used cannot be a buffer or a PO
assert( !Aig_ObjIsBuf(pObjNewR) && !Aig_ObjIsPo(pObjNewR) );
// the object cannot be the same
assert( pObjOld != pObjNewR );
// make sure object is not pointing to itself
assert( pObjOld != Aig_ObjFanin0(pObjNewR) );
assert( pObjOld != Aig_ObjFanin1(pObjNewR) );
// recursively delete the old node - but leave the object there
pObjNewR->nRefs++;
Aig_ObjDelete_rec( p, pObjOld, 0 );
pObjNewR->nRefs--;
// if the new object is complemented or already used, create a buffer
p->nObjs[pObjOld->Type]--;
if ( Aig_IsComplement(pObjNew) || Aig_ObjRefs(pObjNew) > 0 || (fNodesOnly && !Aig_ObjIsNode(pObjNew)) )
{
pObjOld->Type = AIG_OBJ_BUF;
Aig_ObjConnect( p, pObjOld, pObjNew, NULL );
p->nBufReplaces++;
}
else
{
Aig_Obj_t * pFanin0 = pObjNew->pFanin0;
Aig_Obj_t * pFanin1 = pObjNew->pFanin1;
int LevelOld = pObjOld->Level;
pObjOld->Type = pObjNew->Type;
Aig_ObjDisconnect( p, pObjNew );
Aig_ObjConnect( p, pObjOld, pFanin0, pFanin1 );
// delete the new object
Aig_ObjDelete( p, pObjNew );
// update levels
if ( p->pFanData )
{
pObjOld->Level = LevelOld;
Aig_ManUpdateLevel( p, pObjOld );
}
if ( fUpdateLevel )
{
Aig_ObjClearReverseLevel( p, pObjOld );
Aig_ManUpdateReverseLevel( p, pObjOld );
}
}
p->nObjs[pObjOld->Type]++;
// store buffers if fanout is allocated
if ( p->pFanData && Aig_ObjIsBuf(pObjOld) )
{
Vec_PtrPush( p->vBufs, pObjOld );
p->nBufMax = AIG_MAX( p->nBufMax, Vec_PtrSize(p->vBufs) );
Aig_ManPropagateBuffers( p, fNodesOnly, fUpdateLevel );
}
}
/**Function*************************************************************
Synopsis [Duplicates the AIG manager.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Aig_Man_t * Aig_ManDup( Aig_Man_t * p, int fOrdered )
{
Aig_Man_t * pNew;
Aig_Obj_t * pObj;
int i;
// create the new manager
pNew = Aig_ManStart( Aig_ManObjNumMax(p) );
pNew->pName = Aig_UtilStrsav( p->pName );
pNew->nRegs = p->nRegs;
pNew->nAsserts = p->nAsserts;
if ( p->vFlopNums )
pNew->vFlopNums = Vec_IntDup( p->vFlopNums );
// create the PIs
Aig_ManCleanData( p );
Aig_ManConst1(p)->pData = Aig_ManConst1(pNew);
Aig_ManForEachPi( p, pObj, i )
pObj->pData = Aig_ObjCreatePi(pNew);
// duplicate internal nodes
if ( fOrdered )
{
Aig_ManForEachObj( p, pObj, i )
if ( Aig_ObjIsBuf(pObj) )
pObj->pData = Aig_ObjChild0Copy(pObj);
else if ( Aig_ObjIsNode(pObj) )
pObj->pData = Aig_And( pNew, Aig_ObjChild0Copy(pObj), Aig_ObjChild1Copy(pObj) );
}
else
{
/**Function*************************************************************
Synopsis [Duplicates the AIG manager recursively.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Aig_Obj_t * Aig_ManDup_rec( Aig_Man_t * pNew, Aig_Man_t * p, Aig_Obj_t * pObj )
{
if ( pObj->pData )
return pObj->pData;
Aig_ManDup_rec( pNew, p, Aig_ObjFanin0(pObj) );
if ( Aig_ObjIsBuf(pObj) )
return pObj->pData = Aig_ObjChild0Copy(pObj);
Aig_ManDup_rec( pNew, p, Aig_ObjFanin1(pObj) );
return pObj->pData = Aig_And( pNew, Aig_ObjChild0Copy(pObj), Aig_ObjChild1Copy(pObj) );
}
/**Function*************************************************************
Synopsis [Deletes the node.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Aig_ObjDelete( Aig_Man_t * p, Aig_Obj_t * pObj )
{
assert( !Aig_IsComplement(pObj) );
assert( !Aig_ObjIsTerm(pObj) );
assert( Aig_ObjRefs(pObj) == 0 );
if ( p->pFanData && Aig_ObjIsBuf(pObj) )
Vec_PtrRemove( p->vBufs, pObj );
p->nObjs[pObj->Type]--;
Vec_PtrWriteEntry( p->vObjs, pObj->Id, NULL );
Aig_ManRecycleMemory( p, pObj );
}
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Dereferences the node's MFFC.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Aig_NodeDeref_rec( Aig_Obj_t * pNode, unsigned LevelMin, float * pPower, float * pProbs )
{
float Power0 = 0.0, Power1 = 0.0;
Aig_Obj_t * pFanin;
int Counter = 0;
if ( pProbs )
*pPower = 0.0;
if ( Aig_ObjIsCi(pNode) )
return 0;
// consider the first fanin
pFanin = Aig_ObjFanin0(pNode);
assert( pFanin->nRefs > 0 );
if ( --pFanin->nRefs == 0 && (!LevelMin || pFanin->Level > LevelMin) )
Counter += Aig_NodeDeref_rec( pFanin, LevelMin, &Power0, pProbs );
if ( pProbs )
*pPower += Power0 + 2.0 * pProbs[pFanin->Id] * (1.0 - pProbs[pFanin->Id]);
// skip the buffer
if ( Aig_ObjIsBuf(pNode) )
return Counter;
assert( Aig_ObjIsNode(pNode) );
// consider the second fanin
pFanin = Aig_ObjFanin1(pNode);
assert( pFanin->nRefs > 0 );
if ( --pFanin->nRefs == 0 && (!LevelMin || pFanin->Level > LevelMin) )
Counter += Aig_NodeDeref_rec( pFanin, LevelMin, &Power1, pProbs );
if ( pProbs )
*pPower += Power1 + 2.0 * pProbs[pFanin->Id] * (1.0 - pProbs[pFanin->Id]);
return Counter + 1;
}
/**Function*************************************************************
Synopsis [Collects internal nodes in the DFS order.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Aig_ManDfs_rec( Aig_Man_t * p, Aig_Obj_t * pObj, Vec_Ptr_t * vNodes )
{
if ( pObj == NULL )
return;
assert( !Aig_IsComplement(pObj) );
if ( Aig_ObjIsTravIdCurrent(p, pObj) )
return;
assert( Aig_ObjIsNode(pObj) || Aig_ObjIsBuf(pObj) );
Aig_ManDfs_rec( p, Aig_ObjFanin0(pObj), vNodes );
Aig_ManDfs_rec( p, Aig_ObjFanin1(pObj), vNodes );
assert( !Aig_ObjIsTravIdCurrent(p, pObj) ); // loop detection
Aig_ObjSetTravIdCurrent(p, pObj);
Vec_PtrPush( vNodes, pObj );
}
/**Function*************************************************************
Synopsis [Collects internal nodes in the reverse DFS order.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Aig_ManDfsReverse_rec( Aig_Man_t * p, Aig_Obj_t * pObj, Vec_Ptr_t * vNodes )
{
Aig_Obj_t * pFanout;
int iFanout, i;
assert( !Aig_IsComplement(pObj) );
if ( Aig_ObjIsTravIdCurrent(p, pObj) )
return;
assert( Aig_ObjIsNode(pObj) || Aig_ObjIsBuf(pObj) );
Aig_ObjForEachFanout( p, pObj, pFanout, iFanout, i )
Aig_ManDfsReverse_rec( p, pFanout, vNodes );
assert( !Aig_ObjIsTravIdCurrent(p, pObj) ); // loop detection
Aig_ObjSetTravIdCurrent(p, pObj);
Vec_PtrPush( vNodes, pObj );
}
/**Function*************************************************************
Synopsis [References the node's MFFC.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Aig_NodeRef_rec( Aig_Obj_t * pNode, unsigned LevelMin )
{
Aig_Obj_t * pFanin;
int Counter = 0;
if ( Aig_ObjIsPi(pNode) )
return 0;
// consider the first fanin
pFanin = Aig_ObjFanin0(pNode);
if ( pFanin->nRefs++ == 0 && (!LevelMin || pFanin->Level > LevelMin) )
Counter += Aig_NodeRef_rec( pFanin, LevelMin );
// skip the buffer
if ( Aig_ObjIsBuf(pNode) )
return Counter;
assert( Aig_ObjIsNode(pNode) );
// consider the second fanin
pFanin = Aig_ObjFanin1(pNode);
if ( pFanin->nRefs++ == 0 && (!LevelMin || pFanin->Level > LevelMin) )
Counter += Aig_NodeRef_rec( pFanin, LevelMin );
return Counter + 1;
}
/**Function*************************************************************
Synopsis [References the node's MFFC.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Aig_NodeRefLabel_rec( Aig_Man_t * p, Aig_Obj_t * pNode, unsigned LevelMin )
{
Aig_Obj_t * pFanin;
int Counter = 0;
if ( Aig_ObjIsPi(pNode) )
return 0;
Aig_ObjSetTravIdCurrent( p, pNode );
// consider the first fanin
pFanin = Aig_ObjFanin0(pNode);
if ( pFanin->nRefs++ == 0 && (!LevelMin || pFanin->Level > LevelMin) )
Counter += Aig_NodeRefLabel_rec( p, pFanin, LevelMin );
if ( Aig_ObjIsBuf(pNode) )
return Counter;
assert( Aig_ObjIsNode(pNode) );
// consider the second fanin
pFanin = Aig_ObjFanin1(pNode);
if ( pFanin->nRefs++ == 0 && (!LevelMin || pFanin->Level > LevelMin) )
Counter += Aig_NodeRefLabel_rec( p, pFanin, LevelMin );
return Counter + 1;
}
/**Function*************************************************************
Synopsis [Returns the number of dangling nodes removed.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Aig_ManPropagateBuffers( Aig_Man_t * p, int fNodesOnly, int fUpdateLevel )
{
Aig_Obj_t * pObj;
int nSteps;
assert( p->pFanData );
for ( nSteps = 0; Vec_PtrSize(p->vBufs) > 0; nSteps++ )
{
// get the node with a buffer fanin
for ( pObj = Vec_PtrEntryLast(p->vBufs); Aig_ObjIsBuf(pObj); pObj = Aig_ObjFanout0(p, pObj) );
// replace this node by a node without buffer
Aig_NodeFixBufferFanins( p, pObj, fNodesOnly, fUpdateLevel );
// stop if a cycle occured
if ( nSteps > 1000000 )
{
printf( "Error: A cycle is encountered while propagating buffers.\n" );
break;
}
}
return nSteps;
}
/**Function*************************************************************
Synopsis [Collects internal nodes in the reverse DFS order.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Vec_Ptr_t * Aig_ManDfsReverse( Aig_Man_t * p )
{
Vec_Ptr_t * vNodes;
Aig_Obj_t * pObj;
int i;
Aig_ManIncrementTravId( p );
// mark POs
Aig_ManForEachPo( p, pObj, i )
Aig_ObjSetTravIdCurrent( p, pObj );
// if there are latches, mark them
if ( Aig_ManLatchNum(p) > 0 )
Aig_ManForEachObj( p, pObj, i )
if ( Aig_ObjIsLatch(pObj) )
Aig_ObjSetTravIdCurrent( p, pObj );
// go through the nodes
vNodes = Vec_PtrAlloc( Aig_ManNodeNum(p) );
Aig_ManForEachObj( p, pObj, i )
if ( Aig_ObjIsNode(pObj) || Aig_ObjIsBuf(pObj) )
Aig_ManDfsReverse_rec( p, pObj, vNodes );
return vNodes;
}
