Abc_NtkForEachObj( pNtk, pObj, i )
{
// skip constants, PIs, and latches
if ( Abc_ObjFaninNum(pObj) == 0 || Abc_ObjIsLatch(pObj) )
continue;
// process the first fanin
Vec_IntClear( vInitValues );
pFaninNew = Abc_NodeAigToSeq( pObj->pCopy, pObj, 0, vInitValues );
Abc_ObjAddFanin( pObj->pCopy, pFaninNew );
// store the initial values
Vec_IntForEachEntry( vInitValues, Init, k )
Seq_NodeInsertFirst( pObj->pCopy, 0, Init );
// skip single-input nodes
if ( Abc_ObjFaninNum(pObj) == 1 )
continue;
// process the second fanin
Vec_IntClear( vInitValues );
pFaninNew = Abc_NodeAigToSeq( pObj->pCopy, pObj, 1, vInitValues );
Abc_ObjAddFanin( pObj->pCopy, pFaninNew );
// store the initial values
Vec_IntForEachEntry( vInitValues, Init, k )
Seq_NodeInsertFirst( pObj->pCopy, 1, Init );
}
/**Function*************************************************************
Synopsis [Transforms the node to take fanout sharing into account.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Seq_NodeShareOne( Abc_Obj_t * pNode, Abc_InitType_t Init, Vec_Ptr_t * vNodes )
{
Vec_Int_t * vNums = Seq_ObjLNums( pNode );
Vec_Ptr_t * vInits = Seq_NodeLats( pNode );
Abc_Obj_t * pFanout, * pBuffer;
Abc_InitType_t Type, InitNew;
int i;
// collect the fanouts that satisfy the property (have initial value Init or DC)
InitNew = ABC_INIT_DC;
Vec_PtrClear( vNodes );
Abc_ObjForEachFanout( pNode, pFanout, i )
{
if ( Seq_ObjFanoutL(pNode, pFanout) == 0 )
continue;
Type = Seq_NodeGetInitLast( pFanout, Abc_ObjFanoutEdgeNum(pNode, pFanout) );
if ( Type == Init )
InitNew = Init;
if ( Type == Init || Type == ABC_INIT_DC )
{
Vec_PtrPush( vNodes, pFanout );
Seq_NodeDeleteLast( pFanout, Abc_ObjFanoutEdgeNum(pNode, pFanout) );
}
}
// create the new buffer
pBuffer = Abc_NtkCreateNode( pNode->pNtk );
Abc_ObjAddFanin( pBuffer, pNode );
// grow storage for initial states
Vec_PtrGrow( vInits, 2 * pBuffer->Id + 2 );
for ( i = Vec_PtrSize(vInits); i < 2 * (int)pBuffer->Id + 2; i++ )
Vec_PtrPush( vInits, NULL );
// grow storage for numbers of latches
Vec_IntGrow( vNums, 2 * pBuffer->Id + 2 );
for ( i = Vec_IntSize(vNums); i < 2 * (int)pBuffer->Id + 2; i++ )
Vec_IntPush( vNums, 0 );
// insert the new latch
Seq_NodeInsertFirst( pBuffer, 0, InitNew );
// redirect the fanouts
Vec_PtrForEachEntry( vNodes, pFanout, i )
Abc_ObjPatchFanin( pFanout, pNode, pBuffer );
}
/**Function*************************************************************
Synopsis [Retimes node backward by one latch.]
Description [Constructs the problem for initial state computation.
Returns 1 if the conflict is found.]
SideEffects []
SeeAlso []
***********************************************************************/
int Abc_ObjRetimeBackward( Abc_Obj_t * pObj, Abc_Ntk_t * pNtkNew, stmm_table * tTable, Vec_Int_t * vValues )
{
Abc_Obj_t * pFanout;
Abc_InitType_t Init, Value;
Seq_RetEdge_t RetEdge;
Abc_Obj_t * pNodeNew, * pFanoutNew, * pBuffer;
int i, Edge, fMet0, fMet1, fMetN;
// make sure the node can be retimed
assert( Seq_ObjFanoutLMin(pObj) > 0 );
// get the fanout values
fMet0 = fMet1 = fMetN = 0;
Abc_ObjForEachFanout( pObj, pFanout, i )
{
if ( Abc_ObjFaninId0(pFanout) == pObj->Id )
{
Init = Seq_NodeGetInitLast( pFanout, 0 );
if ( Init == ABC_INIT_ZERO )
fMet0 = 1;
else if ( Init == ABC_INIT_ONE )
fMet1 = 1;
else if ( Init == ABC_INIT_NONE )
fMetN = 1;
}
if ( Abc_ObjFaninId1(pFanout) == pObj->Id )
{
Init = Seq_NodeGetInitLast( pFanout, 1 );
if ( Init == ABC_INIT_ZERO )
fMet0 = 1;
else if ( Init == ABC_INIT_ONE )
fMet1 = 1;
else if ( Init == ABC_INIT_NONE )
fMetN = 1;
}
}
// consider the case when all fanout latches have don't-care values
// the new values on the fanin edges will be don't-cares
if ( !fMet0 && !fMet1 && !fMetN )
{
// make sure the label is clean
Abc_ObjForEachFanout( pObj, pFanout, i )
assert( pFanout->fMarkC == 0 );
// update the fanout edges
Abc_ObjForEachFanout( pObj, pFanout, i )
{
if ( pFanout->fMarkC )
continue;
pFanout->fMarkC = 1;
if ( Abc_ObjFaninId0(pFanout) == pObj->Id )
Seq_NodeDeleteLast( pFanout, 0 );
if ( Abc_ObjFaninId1(pFanout) == pObj->Id )
Seq_NodeDeleteLast( pFanout, 1 );
}
// clean the label
Abc_ObjForEachFanout( pObj, pFanout, i )
pFanout->fMarkC = 0;
// update the fanin edges
Abc_ObjRetimeBackwardUpdateEdge( pObj, 0, tTable );
Abc_ObjRetimeBackwardUpdateEdge( pObj, 1, tTable );
Seq_NodeInsertFirst( pObj, 0, ABC_INIT_DC );
Seq_NodeInsertFirst( pObj, 1, ABC_INIT_DC );
return 0;
}
