Version abc80130

1 files changed, 26 insertions, 401 deletions

diff --git a/src/base/abci/abcBalance.c b/src/base/abci/abcBalance.c
index f9b3384e..40701e41 100644
--- a/src/base/abci/abcBalance.c
+++ b/src/base/abci/abcBalance.c
@@ -24,16 +24,13 @@
 ///                        DECLARATIONS                              ///
 ////////////////////////////////////////////////////////////////////////
  
-static void        Abc_NtkBalancePerform( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkAig, bool fDuplicate, bool fSelective, bool fUpdateLevel );
-static Abc_Obj_t * Abc_NodeBalance_rec( Abc_Ntk_t * pNtkNew, Abc_Obj_t * pNode, Vec_Vec_t * vStorage, int Level, bool fDuplicate, bool fSelective, bool fUpdateLevel );
-static Vec_Ptr_t * Abc_NodeBalanceCone( Abc_Obj_t * pNode, Vec_Vec_t * vSuper, int Level, int fDuplicate, bool fSelective );
-static int         Abc_NodeBalanceCone_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst, bool fDuplicate, bool fSelective );
-static void        Abc_NtkMarkCriticalNodes( Abc_Ntk_t * pNtk );
-static Vec_Ptr_t * Abc_NodeBalanceConeExor( Abc_Obj_t * pNode );
-
+static void        Abc_NtkBalancePerform( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkAig, bool fDuplicate );
+static Abc_Obj_t * Abc_NodeBalance_rec( Abc_Ntk_t * pNtkNew, Abc_Obj_t * pNode, Vec_Vec_t * vStorage, bool fDuplicate );
+static Vec_Ptr_t * Abc_NodeBalanceCone( Abc_Obj_t * pNode, Vec_Vec_t * vSuper, int fDuplicate );
+static int         Abc_NodeBalanceCone_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst, bool fDuplicate );
 
 ////////////////////////////////////////////////////////////////////////
-///                     FUNCTION DEFINITIONS                         ///
+///                     FUNCTION DEFITIONS                           ///
 ////////////////////////////////////////////////////////////////////////
 
 /**Function*************************************************************
@@ -47,32 +44,14 @@ static Vec_Ptr_t * Abc_NodeBalanceConeExor( Abc_Obj_t * pNode );
   SeeAlso     []
 
 ***********************************************************************/
-Abc_Ntk_t * Abc_NtkBalance( Abc_Ntk_t * pNtk, bool fDuplicate, bool fSelective, bool fUpdateLevel )
+Abc_Ntk_t * Abc_NtkBalance( Abc_Ntk_t * pNtk, bool fDuplicate )
 {
-    extern void Abc_NtkHaigTranfer( Abc_Ntk_t * pNtkOld, Abc_Ntk_t * pNtkNew );
     Abc_Ntk_t * pNtkAig;
     assert( Abc_NtkIsStrash(pNtk) );
-    // compute the required times
-    if ( fSelective )
-    {
-        Abc_NtkStartReverseLevels( pNtk, 0 );
-        Abc_NtkMarkCriticalNodes( pNtk );
-    }
     // perform balancing
-    pNtkAig = Abc_NtkStartFrom( pNtk, ABC_NTK_STRASH, ABC_FUNC_AIG );
-    // transfer HAIG
-    Abc_NtkHaigTranfer( pNtk, pNtkAig );
-    // perform balancing
-    Abc_NtkBalancePerform( pNtk, pNtkAig, fDuplicate, fSelective, fUpdateLevel );
+    pNtkAig = Abc_NtkStartFrom( pNtk, ABC_TYPE_STRASH, ABC_FUNC_AIG );
+    Abc_NtkBalancePerform( pNtk, pNtkAig, fDuplicate );
     Abc_NtkFinalize( pNtk, pNtkAig );
-    // undo the required times
-    if ( fSelective )
-    {
-        Abc_NtkStopReverseLevels( pNtk );
-        Abc_NtkCleanMarkA( pNtk );
-    }
-    if ( pNtk->pExdc )
-        pNtkAig->pExdc = Abc_NtkDup( pNtk->pExdc );
     // make sure everything is okay
     if ( !Abc_NtkCheck( pNtkAig ) )
     {
@@ -94,7 +73,7 @@ Abc_Ntk_t * Abc_NtkBalance( Abc_Ntk_t * pNtk, bool fDuplicate, bool fSelective,
   SeeAlso     []
 
 ***********************************************************************/
-void Abc_NtkBalancePerform( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkAig, bool fDuplicate, bool fSelective, bool fUpdateLevel )
+void Abc_NtkBalancePerform( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkAig, bool fDuplicate )
 {
     int fCheck = 1;
     ProgressBar * pProgress;
@@ -102,10 +81,12 @@ void Abc_NtkBalancePerform( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkAig, bool fDuplica
     Abc_Obj_t * pNode, * pDriver;
     int i;
 
+    // copy the constant node
+    Abc_AigConst1(pNtk->pManFunc)->pCopy = Abc_AigConst1(pNtkAig->pManFunc);
     // set the level of PIs of AIG according to the arrival times of the old network
     Abc_NtkSetNodeLevelsArrival( pNtk );
     // allocate temporary storage for supergates
-    vStorage = Vec_VecStart( 10 );
+    vStorage = Vec_VecStart( Abc_AigGetLevelNum(pNtk) + 1 );
     // perform balancing of POs
     pProgress = Extra_ProgressBarStart( stdout, Abc_NtkCoNum(pNtk) );
     Abc_NtkForEachCo( pNtk, pNode, i )
@@ -113,7 +94,7 @@ void Abc_NtkBalancePerform( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkAig, bool fDuplica
         Extra_ProgressBarUpdate( pProgress, i, NULL );
         // strash the driver node
         pDriver = Abc_ObjFanin0(pNode);
-        Abc_NodeBalance_rec( pNtkAig, pDriver, vStorage, 0, fDuplicate, fSelective, fUpdateLevel );
+        Abc_NodeBalance_rec( pNtkAig, pDriver, vStorage, fDuplicate );
     }
     Extra_ProgressBarStop( pProgress );
     Vec_VecFree( vStorage );
@@ -121,97 +102,6 @@ void Abc_NtkBalancePerform( Abc_Ntk_t * pNtk, Abc_Ntk_t * pNtkAig, bool fDuplica
 
 /**Function*************************************************************
 
-  Synopsis    [Finds the left bound on the next candidate to be paired.]
-
-  Description [The nodes in the array are in the decreasing order of levels. 
-  The last node in the array has the smallest level. By default it would be paired 
-  with the next node on the left. However, it may be possible to pair it with some
-  other node on the left, in such a way that the new node is shared. This procedure
-  finds the index of the left-most node, which can be paired with the last node.]
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Abc_NodeBalanceFindLeft( Vec_Ptr_t * vSuper )
-{
-    Abc_Obj_t * pNodeRight, * pNodeLeft;
-    int Current;
-    // if two or less nodes, pair with the first
-    if ( Vec_PtrSize(vSuper) < 3 )
-        return 0;
-    // set the pointer to the one before the last
-    Current = Vec_PtrSize(vSuper) - 2;
-    pNodeRight = Vec_PtrEntry( vSuper, Current );
-    // go through the nodes to the left of this one
-    for ( Current--; Current >= 0; Current-- )
-    {
-        // get the next node on the left
-        pNodeLeft = Vec_PtrEntry( vSuper, Current );
-        // if the level of this node is different, quit the loop
-        if ( Abc_ObjRegular(pNodeLeft)->Level != Abc_ObjRegular(pNodeRight)->Level )
-            break;
-    }
-    Current++;    
-    // get the node, for which the equality holds
-    pNodeLeft = Vec_PtrEntry( vSuper, Current );
-    assert( Abc_ObjRegular(pNodeLeft)->Level == Abc_ObjRegular(pNodeRight)->Level );
-    return Current;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Moves closer to the end the node that is best for sharing.]
-
-  Description [If there is no node with sharing, randomly chooses one of 
-  the legal nodes.]
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Abc_NodeBalancePermute( Abc_Ntk_t * pNtkNew, Vec_Ptr_t * vSuper, int LeftBound )
-{
-    Abc_Obj_t * pNode1, * pNode2, * pNode3;
-    int RightBound, i;
-    // get the right bound
-    RightBound = Vec_PtrSize(vSuper) - 2;
-    assert( LeftBound <= RightBound );
-    if ( LeftBound == RightBound )
-        return;
-    // get the two last nodes
-    pNode1 = Vec_PtrEntry( vSuper, RightBound + 1 );
-    pNode2 = Vec_PtrEntry( vSuper, RightBound     );
-    // find the first node that can be shared
-    for ( i = RightBound; i >= LeftBound; i-- )
-    {
-        pNode3 = Vec_PtrEntry( vSuper, i );
-        if ( Abc_AigAndLookup( pNtkNew->pManFunc, pNode1, pNode3 ) )
-        {
-            if ( pNode3 == pNode2 )
-                return;
-            Vec_PtrWriteEntry( vSuper, i,          pNode2 );
-            Vec_PtrWriteEntry( vSuper, RightBound, pNode3 );
-            return;
-        }
-    }
-/*
-    // we did not find the node to share, randomize choice
-    {
-        int Choice = rand() % (RightBound - LeftBound + 1);
-        pNode3 = Vec_PtrEntry( vSuper, LeftBound + Choice );
-        if ( pNode3 == pNode2 )
-            return;
-        Vec_PtrWriteEntry( vSuper, LeftBound + Choice, pNode2 );
-        Vec_PtrWriteEntry( vSuper, RightBound,         pNode3 );
-    }
-*/
-}
-
-/**Function*************************************************************
-
   Synopsis    [Rebalances the multi-input node rooted at pNodeOld.]
 
   Description []
@@ -221,44 +111,36 @@ void Abc_NodeBalancePermute( Abc_Ntk_t * pNtkNew, Vec_Ptr_t * vSuper, int LeftBo
   SeeAlso     []
 
 ***********************************************************************/
-Abc_Obj_t * Abc_NodeBalance_rec( Abc_Ntk_t * pNtkNew, Abc_Obj_t * pNodeOld, Vec_Vec_t * vStorage, int Level, bool fDuplicate, bool fSelective, bool fUpdateLevel )
+Abc_Obj_t * Abc_NodeBalance_rec( Abc_Ntk_t * pNtkNew, Abc_Obj_t * pNodeOld, Vec_Vec_t * vStorage, bool fDuplicate )
 {
     Abc_Aig_t * pMan = pNtkNew->pManFunc;
     Abc_Obj_t * pNodeNew, * pNode1, * pNode2;
     Vec_Ptr_t * vSuper;
-    int i, LeftBound;
+    int i;
     assert( !Abc_ObjIsComplement(pNodeOld) );
     // return if the result if known
     if ( pNodeOld->pCopy )
         return pNodeOld->pCopy;
     assert( Abc_ObjIsNode(pNodeOld) );
     // get the implication supergate
-//    Abc_NodeBalanceConeExor( pNodeOld );
-    vSuper = Abc_NodeBalanceCone( pNodeOld, vStorage, Level, fDuplicate, fSelective );
+    vSuper = Abc_NodeBalanceCone( pNodeOld, vStorage, fDuplicate );
     if ( vSuper->nSize == 0 )
     { // it means that the supergate contains two nodes in the opposite polarity
-        pNodeOld->pCopy = Abc_ObjNot(Abc_AigConst1(pNtkNew));
+        pNodeOld->pCopy = Abc_ObjNot(Abc_AigConst1(pMan));
         return pNodeOld->pCopy;
     }
     // for each old node, derive the new well-balanced node
     for ( i = 0; i < vSuper->nSize; i++ )
     {
-        pNodeNew = Abc_NodeBalance_rec( pNtkNew, Abc_ObjRegular(vSuper->pArray[i]), vStorage, Level + 1, fDuplicate, fSelective, fUpdateLevel );
+        pNodeNew = Abc_NodeBalance_rec( pNtkNew, Abc_ObjRegular(vSuper->pArray[i]), vStorage, fDuplicate );
         vSuper->pArray[i] = Abc_ObjNotCond( pNodeNew, Abc_ObjIsComplement(vSuper->pArray[i]) );
     }
-    if ( vSuper->nSize < 2 )
-        printf( "BUG!\n" );
     // sort the new nodes by level in the decreasing order
     Vec_PtrSort( vSuper, Abc_NodeCompareLevelsDecrease );
     // balance the nodes
     assert( vSuper->nSize > 1 );
     while ( vSuper->nSize > 1 )
     {
-        // find the left bound on the node to be paired
-        LeftBound = (!fUpdateLevel)? 0 : Abc_NodeBalanceFindLeft( vSuper );
-        // find the node that can be shared (if no such node, randomize choice)
-        Abc_NodeBalancePermute( pNtkNew, vSuper, LeftBound );
-        // pull out the last two nodes
         pNode1 = Vec_PtrPop(vSuper);
         pNode2 = Vec_PtrPop(vSuper);
         Abc_VecObjPushUniqueOrderByLevel( vSuper, Abc_AigAnd(pMan, pNode1, pNode2) );
@@ -267,13 +149,6 @@ Abc_Obj_t * Abc_NodeBalance_rec( Abc_Ntk_t * pNtkNew, Abc_Obj_t * pNodeOld, Vec_
     assert( pNodeOld->pCopy == NULL );
     // mark the old node with the new node
     pNodeOld->pCopy = vSuper->pArray[0];
-    vSuper->nSize = 0;
-//    if ( Abc_ObjRegular(pNodeOld->pCopy) == Abc_AigConst1(pNtkNew) )
-//        printf( "Constant node\n" );
-//    assert( pNodeOld->Level >= Abc_ObjRegular(pNodeOld->pCopy)->Level );
-    // update HAIG
-    if ( Abc_ObjRegular(pNodeOld->pCopy)->pNtk->pHaig )
-        Hop_ObjCreateChoice( pNodeOld->pEquiv, Abc_ObjRegular(pNodeOld->pCopy)->pEquiv );
     return pNodeOld->pCopy;
 }
 
@@ -290,25 +165,17 @@ Abc_Obj_t * Abc_NodeBalance_rec( Abc_Ntk_t * pNtkNew, Abc_Obj_t * pNodeOld, Vec_
   SeeAlso     []
 
 ***********************************************************************/
-Vec_Ptr_t * Abc_NodeBalanceCone( Abc_Obj_t * pNode, Vec_Vec_t * vStorage, int Level, int fDuplicate, bool fSelective )
+Vec_Ptr_t * Abc_NodeBalanceCone( Abc_Obj_t * pNode, Vec_Vec_t * vStorage, int fDuplicate )
 {
     Vec_Ptr_t * vNodes;
     int RetValue, i;
     assert( !Abc_ObjIsComplement(pNode) );
-    // extend the storage
-    if ( Vec_VecSize( vStorage ) <= Level )
-        Vec_VecPush( vStorage, Level, 0 );
-    // get the temporary array of nodes
-    vNodes = Vec_VecEntry( vStorage, Level );
+    vNodes = Vec_VecEntry( vStorage, pNode->Level );
     Vec_PtrClear( vNodes );
-    // collect the nodes in the implication supergate
-    RetValue = Abc_NodeBalanceCone_rec( pNode, vNodes, 1, fDuplicate, fSelective );
-    assert( vNodes->nSize > 1 );
-    // unmark the visited nodes
+    RetValue = Abc_NodeBalanceCone_rec( pNode, vNodes, 1, fDuplicate );
+    assert( vNodes->nSize > 0 );
     for ( i = 0; i < vNodes->nSize; i++ )
         Abc_ObjRegular((Abc_Obj_t *)vNodes->pArray[i])->fMarkB = 0;
-    // if we found the node and its complement in the same implication supergate, 
-    // return empty set of nodes (meaning that we should use constant-0 node)
     if ( RetValue == -1 )
         vNodes->nSize = 0;
     return vNodes;
@@ -328,7 +195,7 @@ Vec_Ptr_t * Abc_NodeBalanceCone( Abc_Obj_t * pNode, Vec_Vec_t * vStorage, int Le
   SeeAlso     []
 
 ***********************************************************************/
-int Abc_NodeBalanceCone_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst, bool fDuplicate, bool fSelective )
+int Abc_NodeBalanceCone_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst, bool fDuplicate )
 {
     int RetValue1, RetValue2, i;
     // check if the node is visited
@@ -346,7 +213,7 @@ int Abc_NodeBalanceCone_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst,
         return 0;
     }
     // if the new node is complemented or a PI, another gate begins
-    if ( !fFirst && (Abc_ObjIsComplement(pNode) || !Abc_ObjIsNode(pNode) || !fDuplicate && !fSelective && (Abc_ObjFanoutNum(pNode) > 1)) )
+    if ( !fFirst && (Abc_ObjIsComplement(pNode) || !Abc_ObjIsNode(pNode) || !fDuplicate && (Abc_ObjFanoutNum(pNode) > 1)) )
     {
         Vec_PtrPush( vSuper, pNode );
         Abc_ObjRegular(pNode)->fMarkB = 1;
@@ -355,8 +222,8 @@ int Abc_NodeBalanceCone_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst,
     assert( !Abc_ObjIsComplement(pNode) );
     assert( Abc_ObjIsNode(pNode) );
     // go through the branches
-    RetValue1 = Abc_NodeBalanceCone_rec( Abc_ObjChild0(pNode), vSuper, 0, fDuplicate, fSelective );
-    RetValue2 = Abc_NodeBalanceCone_rec( Abc_ObjChild1(pNode), vSuper, 0, fDuplicate, fSelective );
+    RetValue1 = Abc_NodeBalanceCone_rec( Abc_ObjChild0(pNode), vSuper, 0, fDuplicate );
+    RetValue2 = Abc_NodeBalanceCone_rec( Abc_ObjChild1(pNode), vSuper, 0, fDuplicate );
     if ( RetValue1 == -1 || RetValue2 == -1 )
         return -1;
     // return 1 if at least one branch has a duplicate
@@ -364,248 +231,6 @@ int Abc_NodeBalanceCone_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst,
 }
 
 
-/**Function*************************************************************
-
-  Synopsis    []
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Abc_NodeBalanceConeExor_rec( Abc_Obj_t * pNode, Vec_Ptr_t * vSuper, bool fFirst )
-{
-    int RetValue1, RetValue2, i;
-    // check if the node occurs in the same polarity
-    for ( i = 0; i < vSuper->nSize; i++ )
-        if ( vSuper->pArray[i] == pNode )
-            return 1;
-    // if the new node is complemented or a PI, another gate begins
-    if ( !fFirst && (!pNode->fExor || !Abc_ObjIsNode(pNode)) )
-    {
-        Vec_PtrPush( vSuper, pNode );
-        return 0;
-    }
-    assert( !Abc_ObjIsComplement(pNode) );
-    assert( Abc_ObjIsNode(pNode) );
-    assert( pNode->fExor );
-    // go through the branches
-    RetValue1 = Abc_NodeBalanceConeExor_rec( Abc_ObjFanin0(Abc_ObjFanin0(pNode)), vSuper, 0 );
-    RetValue2 = Abc_NodeBalanceConeExor_rec( Abc_ObjFanin1(Abc_ObjFanin0(pNode)), vSuper, 0 );
-    if ( RetValue1 == -1 || RetValue2 == -1 )
-        return -1;
-    // return 1 if at least one branch has a duplicate
-    return RetValue1 || RetValue2;
-}
-
-/**Function*************************************************************
-
-  Synopsis    []
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-Vec_Ptr_t * Abc_NodeBalanceConeExor( Abc_Obj_t * pNode )
-{
-    Vec_Ptr_t * vSuper;
-    if ( !pNode->fExor )
-        return NULL;
-    vSuper = Vec_PtrAlloc( 10 );
-    Abc_NodeBalanceConeExor_rec( pNode, vSuper, 1 );
-    printf( "%d ", Vec_PtrSize(vSuper) );
-    Vec_PtrFree( vSuper );
-    return NULL;
-}
-
-
-
-/**Function*************************************************************
-
-  Synopsis    [Collects the nodes in the implication supergate.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-Vec_Ptr_t * Abc_NodeFindCone_rec( Abc_Obj_t * pNode )
-{
-    Vec_Ptr_t * vNodes;
-    Abc_Obj_t * pNodeC, * pNodeT, * pNodeE;
-    int RetValue, i;
-    assert( !Abc_ObjIsComplement(pNode) );
-    if ( Abc_ObjIsCi(pNode) )
-        return NULL;
-    // start the new array
-    vNodes = Vec_PtrAlloc( 4 );
-    // if the node is the MUX collect its fanins
-    if ( Abc_NodeIsMuxType(pNode) )
-    {
-        pNodeC = Abc_NodeRecognizeMux( pNode, &pNodeT, &pNodeE );
-        Vec_PtrPush( vNodes, Abc_ObjRegular(pNodeC) );
-        Vec_PtrPushUnique( vNodes, Abc_ObjRegular(pNodeT) );
-        Vec_PtrPushUnique( vNodes, Abc_ObjRegular(pNodeE) );
-    }
-    else
-    {
-        // collect the nodes in the implication supergate
-        RetValue = Abc_NodeBalanceCone_rec( pNode, vNodes, 1, 1, 0 );
-        assert( vNodes->nSize > 1 );
-        // unmark the visited nodes
-        Vec_PtrForEachEntry( vNodes, pNode, i )
-            Abc_ObjRegular(pNode)->fMarkB = 0;
-        // if we found the node and its complement in the same implication supergate, 
-        // return empty set of nodes (meaning that we should use constant-0 node)
-        if ( RetValue == -1 )
-            vNodes->nSize = 0;
-    }
-    // call for the fanin
-    Vec_PtrForEachEntry( vNodes, pNode, i )
-    {
-        pNode = Abc_ObjRegular(pNode);
-        if ( pNode->pCopy )
-            continue;
-        pNode->pCopy = (Abc_Obj_t *)Abc_NodeFindCone_rec( pNode );
-    }
-    return vNodes;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Attaches the implication supergates to internal nodes.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Abc_NtkBalanceAttach( Abc_Ntk_t * pNtk )
-{
-    Abc_Obj_t * pNode;
-    int i;
-    Abc_NtkCleanCopy( pNtk );
-    Abc_NtkForEachCo( pNtk, pNode, i )
-    {
-        pNode = Abc_ObjFanin0(pNode);
-        if ( pNode->pCopy )
-            continue;
-        pNode->pCopy = (Abc_Obj_t *)Abc_NodeFindCone_rec( pNode );
-    }
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Attaches the implication supergates to internal nodes.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Abc_NtkBalanceDetach( Abc_Ntk_t * pNtk )
-{
-    Abc_Obj_t * pNode;
-    int i;
-    Abc_NtkForEachNode( pNtk, pNode, i )
-        if ( pNode->pCopy )
-        {
-            Vec_PtrFree( (Vec_Ptr_t *)pNode->pCopy );
-            pNode->pCopy = NULL;
-        }
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Compute levels of implication supergates.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Abc_NtkBalanceLevel_rec( Abc_Obj_t * pNode )
-{
-    Vec_Ptr_t * vSuper;
-    Abc_Obj_t * pFanin;
-    int i, LevelMax;
-    assert( !Abc_ObjIsComplement(pNode) );
-    if ( pNode->Level > 0 )
-        return pNode->Level;
-    if ( Abc_ObjIsCi(pNode) )
-        return 0;
-    vSuper = (Vec_Ptr_t *)pNode->pCopy;
-    assert( vSuper != NULL );
-    LevelMax = 0;
-    Vec_PtrForEachEntry( vSuper, pFanin, i )
-    {
-        pFanin = Abc_ObjRegular(pFanin);
-        Abc_NtkBalanceLevel_rec(pFanin);
-        if ( LevelMax < (int)pFanin->Level )
-            LevelMax = pFanin->Level;
-    }
-    pNode->Level = LevelMax + 1;
-    return pNode->Level;
-}
-
-
-/**Function*************************************************************
-
-  Synopsis    [Compute levels of implication supergates.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Abc_NtkBalanceLevel( Abc_Ntk_t * pNtk )
-{
-    Abc_Obj_t * pNode;
-    int i;
-    Abc_NtkForEachObj( pNtk, pNode, i )
-        pNode->Level = 0;
-    Abc_NtkForEachCo( pNtk, pNode, i )
-        Abc_NtkBalanceLevel_rec( Abc_ObjFanin0(pNode) );
-}
-
-
-/**Function*************************************************************
-
-  Synopsis    [Marks the nodes on the critical and near critical paths.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Abc_NtkMarkCriticalNodes( Abc_Ntk_t * pNtk )
-{
-    Abc_Obj_t * pNode;
-    int i, Counter = 0;
-    Abc_NtkForEachNode( pNtk, pNode, i )
-        if ( Abc_ObjRequiredLevel(pNode) - pNode->Level <= 1 )
-            pNode->fMarkA = 1, Counter++;
-    printf( "The number of nodes on the critical paths = %6d  (%5.2f %%)\n", Counter, 100.0 * Counter / Abc_NtkNodeNum(pNtk) );
-}
-
-
 ////////////////////////////////////////////////////////////////////////
 ///                       END OF FILE                                ///
 ////////////////////////////////////////////////////////////////////////