Upgrading hierarchy timing manager.

17 files changed, 1455 insertions, 997 deletions

diff --git a/abclib.dsp b/abclib.dsp
index 1b55591a..5bb5a374 100644
--- a/abclib.dsp
+++ b/abclib.dsp
@@ -2905,6 +2905,30 @@ SOURCE=.\src\misc\tim\tim.c
 
 SOURCE=.\src\misc\tim\tim.h
 # End Source File
+# Begin Source File
+
+SOURCE=.\src\misc\tim\timBox.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\src\misc\tim\timDump.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\src\misc\tim\timInt.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\src\misc\tim\timMan.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\src\misc\tim\timTime.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\src\misc\tim\timTrav.c
+# End Source File
 # End Group
 # End Group
 # Begin Group "ai"
diff --git a/src/aig/gia/giaAiger.c b/src/aig/gia/giaAiger.c
index 0fbe1ee6..f304c644 100644
--- a/src/aig/gia/giaAiger.c
+++ b/src/aig/gia/giaAiger.c
@@ -20,6 +20,7 @@
 ***********************************************************************/
 
 #include "gia.h"
+#include "misc/tim/tim.h"
 
 ABC_NAMESPACE_IMPL_START
 
@@ -872,6 +873,17 @@ Gia_Man_t * Gia_ReadAigerFromMemory( char * pContents, int nFileSize, int fSkipS
             // read switching activity
             pNew->pSwitching = Gia_ReadSwitching( &pCur, Gia_ManObjNum(pNew) );
         }
+        if ( *pCur == 't' )
+        {
+            Vec_Str_t * vStr;
+            pCur++;
+            // read timing manager
+            vStr = Vec_StrStart( Gia_ReadInt(pCur) ); pCur += 4;
+            memcpy( Vec_StrArray(vStr), pCur, Vec_StrSize(vStr) );
+            pCur += Vec_StrSize(vStr);
+            pNew->pManTime = Tim_ManLoad( vStr );
+            Vec_StrFree( vStr );
+        }
         if ( *pCur == 'c' )
         {
             pCur++;
@@ -1046,10 +1058,12 @@ Gia_Man_t * Gia_ReadAigerFromMemory( char * pContents, int nFileSize, int fSkipS
 
     if ( Gia_ManHasDangling(pNew) )
     {
+        Tim_Man_t * pManTime;
         Vec_Int_t * vFlopMap, * vGateMap, * vObjMap;
         vFlopMap = pNew->vFlopClasses; pNew->vFlopClasses = NULL;
         vGateMap = pNew->vGateClasses; pNew->vGateClasses = NULL;
         vObjMap  = pNew->vObjClasses;  pNew->vObjClasses  = NULL;
+        pManTime = pNew->pManTime;     pNew->pManTime     = NULL;
         pNew = Gia_ManCleanup( pTemp = pNew );
         if ( (vGateMap || vObjMap) && (Gia_ManObjNum(pNew) < Gia_ManObjNum(pTemp)) )
             printf( "Cleanup removed objects after reading. Old gate/object abstraction maps are invalid!\n" );
@@ -1057,6 +1071,7 @@ Gia_Man_t * Gia_ReadAigerFromMemory( char * pContents, int nFileSize, int fSkipS
         pNew->vFlopClasses = vFlopMap;
         pNew->vGateClasses = vGateMap;
         pNew->vObjClasses  = vObjMap;
+        pNew->pManTime     = pManTime;
     }
     return pNew;
 }
@@ -1377,8 +1392,11 @@ void Gia_WriteAiger( Gia_Man_t * pInit, char * pFileName, int fWriteSymbols, int
     // create normalized AIG
     if ( !Gia_ManIsNormalized(pInit) )
     {
+        Tim_Man_t * pManTime;
+        pManTime = pInit->pManTime;    pInit->pManTime     = NULL;
 //        printf( "Gia_WriteAiger(): Normalizing AIG for writing.\n" );
         p = Gia_ManDupNormalized( pInit );
+        p->pManTime = pManTime;
     }
     else
         p = pInit;
@@ -1519,7 +1537,7 @@ void Gia_WriteAiger( Gia_Man_t * pInit, char * pFileName, int fWriteSymbols, int
         fwrite( Buffer, 1, 4, pFile );
         fwrite( p->pPlacement, 1, nSize, pFile );
     }
-    // write flop classes
+    // write switching activity
     if ( p->pSwitching )
     {
         unsigned char Buffer[10];
@@ -1529,6 +1547,18 @@ void Gia_WriteAiger( Gia_Man_t * pInit, char * pFileName, int fWriteSymbols, int
         fwrite( Buffer, 1, 4, pFile );
         fwrite( p->pSwitching, 1, nSize, pFile );
     }
+    // write timing information
+    if ( p->pManTime )
+    {
+        Vec_Str_t * vStr = Tim_ManSave( p->pManTime );
+        unsigned char Buffer[10];
+        int nSize = Vec_StrSize(vStr);
+        Gia_WriteInt( Buffer, nSize );
+        fprintf( pFile, "t" );
+        fwrite( Buffer, 1, 4, pFile );
+        fwrite( Vec_StrArray(vStr), 1, nSize, pFile );
+        Vec_StrFree( vStr );
+    }
 /*
     // write constraints
     if ( p->nConstrs )
diff --git a/src/aig/gia/giaSpeedup.c b/src/aig/gia/giaSpeedup.c
index be9a8654..835f2c15 100644
--- a/src/aig/gia/giaSpeedup.c
+++ b/src/aig/gia/giaSpeedup.c
@@ -279,7 +279,7 @@ float Gia_ManDelayTraceLut( Gia_Man_t * p )
     if ( p->pManTime )
     {
         Tim_ManIncrementTravId( (Tim_Man_t *)p->pManTime );
-        Tim_ManSetCoRequiredAll( (Tim_Man_t *)p->pManTime, tArrival );
+        Tim_ManInitPoRequiredAll( (Tim_Man_t *)p->pManTime, tArrival );
     }
     else
     {
diff --git a/src/map/if/if.h b/src/map/if/if.h
index 37cea625..f74a59da 100644
--- a/src/map/if/if.h
+++ b/src/map/if/if.h
@@ -128,7 +128,6 @@ struct If_Par_t_
     int                fUseSops;      // use local SOPs as a cost function
     int                fUseCnfs;      // use local CNFs as a cost function
     int                fUseMv;        // use local MV-SOPs as a cost function
-    int                fUseAdders;    // timing model for adders
     int                nLatchesCi;    // the number of latches among the CIs
     int                nLatchesCo;    // the number of latches among the COs
     int                nLatchesCiBox; // the number of white box outputs among the CIs
@@ -531,8 +530,8 @@ extern int             If_ManCountSpecialPos( If_Man_t * p );
 extern int             If_CutDelayRecCost(If_Man_t* p, If_Cut_t* pCut, If_Obj_t * pObj);
 extern int             If_CutDelayRecCost2(If_Man_t* p, If_Cut_t* pCut, If_Obj_t * pObj);
 /*=== abcRec2.c ============================================================*/
-extern int             Abc_NtkRecIsRunning();
-extern int             Abc_NtkRecIsRunning2();
+extern ABC_DLL int     Abc_NtkRecIsRunning();
+extern ABC_DLL int     Abc_NtkRecIsRunning2();
 
 // othe packages
 extern int             Bat_ManCellFuncLookup( unsigned * pTruth, int nVars, int nLeaves );
diff --git a/src/map/if/ifUtil.c b/src/map/if/ifUtil.c
index ccbb258e..4d904613 100644
--- a/src/map/if/ifUtil.c
+++ b/src/map/if/ifUtil.c
@@ -286,7 +286,7 @@ void If_ManComputeRequired( If_Man_t * p )
         }
         else  
         {
-            Tim_ManSetCoRequiredAll( p->pManTim, p->RequiredGlo );
+            Tim_ManInitPoRequiredAll( p->pManTim, p->RequiredGlo );
 //            If_ManForEachCo( p, pObj, i )
 //                Tim_ManSetCoRequired( p->pManTim, pObj->IdPio, p->RequiredGlo );
         }
diff --git a/src/misc/tim/module.make b/src/misc/tim/module.make
index 62a3ede5..00609901 100644
--- a/src/misc/tim/module.make
+++ b/src/misc/tim/module.make
@@ -1 +1,6 @@
-SRC +=    src/misc/tim/tim.c
+SRC +=    src/misc/tim/tim.c \
+    src/misc/tim/timBox.c \
+    src/misc/tim/timDump.c \
+    src/misc/tim/timMan.c \
+    src/misc/tim/timTime.c \
+    src/misc/tim/timTrav.c
diff --git a/src/misc/tim/tim.c b/src/misc/tim/tim.c
index 4e60c216..ebbbaf02 100644
--- a/src/misc/tim/tim.c
+++ b/src/misc/tim/tim.c
@@ -4,7 +4,7 @@
 
   SystemName  [ABC: Logic synthesis and verification system.]
 
-  PackageName [A timing manager.]
+  PackageName [Hierarchy/timing manager.]
 
   Synopsis    [Representation of timing information.]
 
@@ -18,975 +18,18 @@
 
 ***********************************************************************/
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <assert.h>
-
-#include "misc/vec/vec.h"
-#include "misc/mem/mem.h"
-#include "tim.h"
+#include "timInt.h"
 
 ABC_NAMESPACE_IMPL_START
 
-
 ////////////////////////////////////////////////////////////////////////
 ///                        DECLARATIONS                              ///
 ////////////////////////////////////////////////////////////////////////
 
-typedef struct Tim_Box_t_           Tim_Box_t;
-typedef struct Tim_Obj_t_           Tim_Obj_t;
-
-// timing manager
-struct Tim_Man_t_
-{
-    Vec_Ptr_t *      vBoxes;         // the timing boxes
-    Vec_Ptr_t *      vDelayTables;   // pointers to the delay tables
-    Mem_Flex_t *     pMemObj;        // memory manager for boxes
-    int              nTravIds;       // traversal ID of the manager
-    int              fUseTravId;     // enables the use of traversal ID
-    int              nCis;           // the number of PIs
-    int              nCos;           // the number of POs
-    Tim_Obj_t *      pCis;           // timing info for the PIs
-    Tim_Obj_t *      pCos;           // timing info for the POs
-};
-
-// timing box
-struct Tim_Box_t_
-{
-    int              iBox;           // the unique ID of this box
-    int              TravId;         // traversal ID of this box
-    int              nInputs;        // the number of box inputs (POs)
-    int              nOutputs;       // the number of box outputs (PIs)
-    float *          pDelayTable;    // delay for each input->output path
-    int              Inouts[0];      // the int numbers of PIs and POs
-};
-
-// timing object
-struct Tim_Obj_t_
-{
-    int              Id;             // the ID of this object
-    int              TravId;         // traversal ID of this object
-    int              iObj2Box;       // mapping of the object into its box
-    int              iObj2Num;       // mapping of the object into its number in the box
-    float            timeArr;        // arrival time of the object
-    float            timeReq;        // required time of the object
-};
-
-static inline Tim_Obj_t * Tim_ManCi( Tim_Man_t * p, int i )                           { assert( i < p->nCis ); return p->pCis + i;      }
-static inline Tim_Obj_t * Tim_ManCo( Tim_Man_t * p, int i )                           { assert( i < p->nCos ); return p->pCos + i;      }
-static inline Tim_Box_t * Tim_ManBox( Tim_Man_t * p, int i )                          { return (Tim_Box_t *)Vec_PtrEntry(p->vBoxes, i); }
-
-static inline Tim_Box_t * Tim_ManCiBox( Tim_Man_t * p, int i )                        { return Tim_ManCi(p,i)->iObj2Box < 0 ? NULL : (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, Tim_ManCi(p,i)->iObj2Box ); }
-static inline Tim_Box_t * Tim_ManCoBox( Tim_Man_t * p, int i )                        { return Tim_ManCo(p,i)->iObj2Box < 0 ? NULL : (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, Tim_ManCo(p,i)->iObj2Box ); }
-
-static inline Tim_Obj_t * Tim_ManBoxInput( Tim_Man_t * p, Tim_Box_t * pBox, int i )   { assert( i < pBox->nInputs  ); return p->pCos + pBox->Inouts[i];               }
-static inline Tim_Obj_t * Tim_ManBoxOutput( Tim_Man_t * p, Tim_Box_t * pBox, int i )  { assert( i < pBox->nOutputs ); return p->pCis + pBox->Inouts[pBox->nInputs+i]; }
-
-#define Tim_ManBoxForEachInput( p, pBox, pObj, i )                               \
-    for ( i = 0; (i < (pBox)->nInputs) && ((pObj) = Tim_ManBoxInput(p, pBox, i)); i++ )
-#define Tim_ManBoxForEachOutput( p, pBox, pObj, i )                              \
-    for ( i = 0; (i < (pBox)->nOutputs) && ((pObj) = Tim_ManBoxOutput(p, pBox, i)); i++ )
-
-#define Tim_ManForEachCi( p, pObj, i )                                           \
-    for ( i = 0; (i < (p)->nCis) && ((pObj) = (p)->pCis + i); i++ )              \
-        if ( pObj->iObj2Box >= 0 ) {} else 
-#define Tim_ManForEachCo( p, pObj, i )                                           \
-    for ( i = 0; (i < (p)->nCos) && ((pObj) = (p)->pCos + i); i++ )              \
-        if ( pObj->iObj2Box >= 0 ) {} else 
-#define Tim_ManForEachBox( p, pBox, i )                                          \
-    Vec_PtrForEachEntry( Tim_Box_t *, p->vBoxes, pBox, i )
-
 ////////////////////////////////////////////////////////////////////////
 ///                     FUNCTION DEFINITIONS                         ///
 ////////////////////////////////////////////////////////////////////////
 
-/**Function*************************************************************
-
-  Synopsis    [Starts the timing manager.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-Tim_Man_t * Tim_ManStart( int nCis, int nCos )
-{
-    Tim_Man_t * p;
-    int i;
-    p = ABC_ALLOC( Tim_Man_t, 1 );
-    memset( p, 0, sizeof(Tim_Man_t) );
-    p->pMemObj = Mem_FlexStart();
-    p->vBoxes  = Vec_PtrAlloc( 100 );
-    p->nCis = nCis;
-    p->nCos = nCos;
-    p->pCis = ABC_ALLOC( Tim_Obj_t, nCis );
-    memset( p->pCis, 0, sizeof(Tim_Obj_t) * nCis );
-    p->pCos = ABC_ALLOC( Tim_Obj_t, nCos );
-    memset( p->pCos, 0, sizeof(Tim_Obj_t) * nCos );
-    for ( i = 0; i < nCis; i++ )
-    {
-        p->pCis[i].Id = i;
-        p->pCis[i].iObj2Box = p->pCis[i].iObj2Num = -1;
-        p->pCis[i].timeReq = TIM_ETERNITY;
-        p->pCis[i].timeArr = 0.0;
-        p->pCis[i].TravId = 0;
-    }
-    for ( i = 0; i < nCos; i++ )
-    {
-        p->pCos[i].Id = i;
-        p->pCos[i].iObj2Box = p->pCos[i].iObj2Num = -1;
-        p->pCos[i].timeReq = TIM_ETERNITY;
-        p->pCos[i].timeArr = 0.0;
-        p->pCos[i].TravId = 0;
-    }
-    p->fUseTravId = 1;
-    return p;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Duplicates the timing manager.]
-
-  Description [Derives discrete-delay-model timing manager. 
-  Useful for AIG optimization with approximate timing information.]
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-Tim_Man_t * Tim_ManDup( Tim_Man_t * p, int fDiscrete )
-{
-    Tim_Man_t * pNew;
-    Tim_Box_t * pBox;
-    float * pDelayTableNew;
-    int i, k;
-    pNew = Tim_ManStart( p->nCis, p->nCos );
-    memcpy( pNew->pCis, p->pCis, sizeof(Tim_Obj_t) * p->nCis );
-    memcpy( pNew->pCos, p->pCos, sizeof(Tim_Obj_t) * p->nCos );
-    for ( k = 0; k < p->nCis; k++ )
-        pNew->pCis[k].TravId = 0;
-    for ( k = 0; k < p->nCos; k++ )
-        pNew->pCos[k].TravId = 0;
-    if ( fDiscrete )
-    {
-        for ( k = 0; k < p->nCis; k++ )
-            pNew->pCis[k].timeArr = 0.0; // modify here
-        // modify the required times
-    }
-    pNew->vDelayTables = Vec_PtrAlloc( 100 );
-    Tim_ManForEachBox( p, pBox, i )
-    {
-//printf( "%d %d\n", pBox->nInputs, pBox->nOutputs );
-        pDelayTableNew = ABC_ALLOC( float, pBox->nInputs * pBox->nOutputs );
-        Vec_PtrPush( pNew->vDelayTables, pDelayTableNew );
-        if ( fDiscrete )
-        {
-            for ( k = 0; k < pBox->nInputs * pBox->nOutputs; k++ )
-                pDelayTableNew[k] = 1.0; // modify here
-
-///// begin part of improved CIN/COUT propagation
-            for ( k = 0; k < pBox->nInputs; k++ )  // fill in the first row
-               pDelayTableNew[k] = 0.5;
-            for ( k = 0; k < pBox->nOutputs; k++ ) // fill in the first column
-               pDelayTableNew[k*pBox->nInputs] = 0.5;
-            pDelayTableNew[0] = 0.0; // fill in the first entry 
-///// end part of improved CIN/COUT propagation
-
-            /// change
-//            pDelayTableNew[0] = 0.0;
-            /// change
-        }
-        else
-            memcpy( pDelayTableNew, pBox->pDelayTable, sizeof(float) * pBox->nInputs * pBox->nOutputs );
-        Tim_ManCreateBoxFirst( pNew, pBox->Inouts[0], pBox->nInputs, 
-            pBox->Inouts[pBox->nInputs], pBox->nOutputs, pDelayTableNew );
-    }
-    return pNew;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Duplicates the timing manager.]
-
-  Description [Derives unit-delay-model timing manager. 
-  Useful for levelizing the network.]
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-Tim_Man_t * Tim_ManDupUnit( Tim_Man_t * p )
-{
-    Tim_Man_t * pNew;
-    Tim_Box_t * pBox;
-    float * pDelayTableNew;
-    int i, k;
-    pNew = Tim_ManStart( p->nCis, p->nCos );
-    memcpy( pNew->pCis, p->pCis, sizeof(Tim_Obj_t) * p->nCis );
-    memcpy( pNew->pCos, p->pCos, sizeof(Tim_Obj_t) * p->nCos );
-    for ( k = 0; k < p->nCis; k++ )
-    {
-        pNew->pCis[k].TravId = 0;
-        pNew->pCis[k].timeArr = 0.0; 
-    }
-    for ( k = 0; k < p->nCos; k++ )
-        pNew->pCos[k].TravId = 0;
-    pNew->vDelayTables = Vec_PtrAlloc( 100 );
-    Tim_ManForEachBox( p, pBox, i )
-    {
-        pDelayTableNew = ABC_ALLOC( float, pBox->nInputs * pBox->nOutputs );
-        Vec_PtrPush( pNew->vDelayTables, pDelayTableNew );
-        for ( k = 0; k < pBox->nInputs * pBox->nOutputs; k++ )
-            pDelayTableNew[k] = 1.0;
-        Tim_ManCreateBoxFirst( pNew, pBox->Inouts[0], pBox->nInputs, 
-            pBox->Inouts[pBox->nInputs], pBox->nOutputs, pDelayTableNew );
-    }
-    return pNew;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Duplicates the timing manager.]
-
-  Description [Derives the approximate timing manager with realistic delays
-  but without white-boxes.]
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-Tim_Man_t * Tim_ManDupApprox( Tim_Man_t * p )
-{
-    Tim_Man_t * pNew;
-    int k;
-    pNew = Tim_ManStart( p->nCis, p->nCos );
-    for ( k = 0; k < p->nCis; k++ )
-        if ( p->pCis[k].iObj2Box == -1 )
-            pNew->pCis[k].timeArr = p->pCis[k].timeArr;
-        else
-            pNew->pCis[k].timeArr = p->pCis[k].timeReq;
-    for ( k = 0; k < p->nCos; k++ )
-        pNew->pCos[k].timeReq = p->pCos[k].timeReq;
-    return pNew;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Stops the timing manager.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManStop( Tim_Man_t * p )
-{
-    float * pTable;
-    int i;
-    if ( p->vDelayTables )
-    {
-        Vec_PtrForEachEntry( float *, p->vDelayTables, pTable, i )
-            ABC_FREE( pTable );
-        Vec_PtrFree( p->vDelayTables );
-    }
-    Vec_PtrFree( p->vBoxes );
-    Mem_FlexStop( p->pMemObj, 0 );
-    ABC_FREE( p->pCis );
-    ABC_FREE( p->pCos );
-    ABC_FREE( p );
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Stops the timing manager.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManStopP( Tim_Man_t ** p )
-{
-    if ( *p == NULL )
-        return;
-    Tim_ManStop( *p );
-    *p = NULL;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Stops the timing manager.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManPrint( Tim_Man_t * p )
-{
-    Tim_Box_t * pBox;
-    Tim_Obj_t * pObj;
-    int i;
-    printf( "TIMING INFORMATION:\n" );
-    Tim_ManForEachCi( p, pObj, i )
-        printf( "pi%5d :  arr = %5.3f  req = %5.3f\n", i, pObj->timeArr, pObj->timeReq );
-    Tim_ManForEachCo( p, pObj, i )
-        printf( "po%5d :  arr = %5.3f  req = %5.3f\n", i, pObj->timeArr, pObj->timeReq );
-    Tim_ManForEachBox( p, pBox, i )
-    {
-        printf( "*** Box %3d :  Ins = %d. Outs = %d.\n", i, pBox->nInputs, pBox->nOutputs );
-        printf( "Delay table:" );
-        for ( i = 0; i < pBox->nInputs * pBox->nOutputs; i++ )
-            printf( " %5.3f", pBox->pDelayTable[i] );
-        printf( "\n" );
-        Tim_ManBoxForEachInput( p, pBox, pObj, i )
-            printf( "box-inp%3d :  arr = %5.3f  req = %5.3f\n", i, pObj->timeArr, pObj->timeReq );
-        Tim_ManBoxForEachOutput( p, pBox, pObj, i )
-            printf( "box-out%3d :  arr = %5.3f  req = %5.3f\n", i, pObj->timeArr, pObj->timeReq );
-    }
-    printf( "\n" );
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Disables the use of the traversal ID.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManTravIdDisable( Tim_Man_t * p )
-{
-    p->fUseTravId = 0;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Enables the use of the traversal ID.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManTravIdEnable( Tim_Man_t * p )
-{
-    p->fUseTravId = 1;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Label box inputs.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetCurrentTravIdBoxInputs( Tim_Man_t * p, int iBox )
-{
-    Tim_Box_t * pBox;
-    Tim_Obj_t * pObj;
-    int i;
-    pBox = Tim_ManBox( p, iBox );
-    Tim_ManBoxForEachInput( p, pBox, pObj, i )
-        pObj->TravId = p->nTravIds;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Label box outputs.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetCurrentTravIdBoxOutputs( Tim_Man_t * p, int iBox )
-{
-    Tim_Box_t * pBox;
-    Tim_Obj_t * pObj;
-    int i;
-    pBox = Tim_ManBox( p, iBox );
-    Tim_ManBoxForEachOutput( p, pBox, pObj, i )
-        pObj->TravId = p->nTravIds;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Label box inputs.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetPreviousTravIdBoxInputs( Tim_Man_t * p, int iBox )
-{
-    Tim_Box_t * pBox;
-    Tim_Obj_t * pObj;
-    int i;
-    pBox = Tim_ManBox( p, iBox );
-    Tim_ManBoxForEachInput( p, pBox, pObj, i )
-        pObj->TravId = p->nTravIds - 1;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Label box outputs.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetPreviousTravIdBoxOutputs( Tim_Man_t * p, int iBox )
-{
-    Tim_Box_t * pBox;
-    Tim_Obj_t * pObj;
-    int i;
-    pBox = Tim_ManBox( p, iBox );
-    Tim_ManBoxForEachOutput( p, pBox, pObj, i )
-        pObj->TravId = p->nTravIds - 1;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Updates required time of the PO.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Tim_ManIsCiTravIdCurrent( Tim_Man_t * p, int iCi )
-{
-    assert( iCi < p->nCis );
-    assert( p->fUseTravId );
-    return p->pCis[iCi].TravId == p->nTravIds;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Updates required time of the PO.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Tim_ManIsCoTravIdCurrent( Tim_Man_t * p, int iCo )
-{
-    assert( iCo < p->nCos );
-    assert( p->fUseTravId );
-    return p->pCos[iCo].TravId == p->nTravIds;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Sets the vector of timing tables associated with the manager.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetDelayTables( Tim_Man_t * p, Vec_Ptr_t * vDelayTables )
-{
-    assert( p->vDelayTables == NULL );
-    p->vDelayTables = vDelayTables;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Creates the new timing box.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManCreateBox( Tim_Man_t * p, int * pIns, int nIns, int * pOuts, int nOuts, float * pDelayTable )
-{
-    Tim_Box_t * pBox;
-    int i;
-    pBox = (Tim_Box_t *)Mem_FlexEntryFetch( p->pMemObj, sizeof(Tim_Box_t) + sizeof(int) * (nIns+nOuts) );
-    memset( pBox, 0, sizeof(Tim_Box_t) );
-    pBox->iBox = Vec_PtrSize( p->vBoxes );
-    Vec_PtrPush( p->vBoxes, pBox );
-    pBox->pDelayTable = pDelayTable;
-    pBox->nInputs  = nIns;
-    pBox->nOutputs = nOuts;
-    for ( i = 0; i < nIns; i++ )
-    {
-        assert( pIns[i] < p->nCos );
-        pBox->Inouts[i] = pIns[i];
-        p->pCos[pIns[i]].iObj2Box = pBox->iBox;
-        p->pCos[pIns[i]].iObj2Num = i;
-    }
-    for ( i = 0; i < nOuts; i++ )
-    {
-        assert( pOuts[i] < p->nCis );
-        pBox->Inouts[nIns+i] = pOuts[i];
-        p->pCis[pOuts[i]].iObj2Box = pBox->iBox;
-        p->pCis[pOuts[i]].iObj2Num = i;
-    }
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Creates the new timing box.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManCreateBoxFirst( Tim_Man_t * p, int firstIn, int nIns, int firstOut, int nOuts, float * pDelayTable )
-{
-    Tim_Box_t * pBox;
-    int i;
-//    printf( "Creating %d x %d box with first inputs (%d and %d).\n", nIns, nOuts, firstIn, firstOut );
-
-    pBox = (Tim_Box_t *)Mem_FlexEntryFetch( p->pMemObj, sizeof(Tim_Box_t) + sizeof(int) * (nIns+nOuts) );
-    memset( pBox, 0, sizeof(Tim_Box_t) );
-    pBox->iBox = Vec_PtrSize( p->vBoxes );
-    Vec_PtrPush( p->vBoxes, pBox );
-    pBox->pDelayTable = pDelayTable;
-    pBox->nInputs  = nIns;
-    pBox->nOutputs = nOuts;
-    for ( i = 0; i < nIns; i++ )
-    {
-        assert( firstIn+i < p->nCos );
-        pBox->Inouts[i] = firstIn+i;
-        p->pCos[firstIn+i].iObj2Box = pBox->iBox;
-        p->pCos[firstIn+i].iObj2Num = i;
-    }
-    for ( i = 0; i < nOuts; i++ )
-    {
-        assert( firstOut+i < p->nCis );
-        pBox->Inouts[nIns+i] = firstOut+i;
-        p->pCis[firstOut+i].iObj2Box = pBox->iBox;
-        p->pCis[firstOut+i].iObj2Num = i;
-    }
-//    if ( pBox->iBox < 50 )
-//    printf( "%4d  %4d  %4d  %4d  \n", firstIn, nIns, firstOut, nOuts );
-}
-
-
-
-/**Function*************************************************************
-
-  Synopsis    [Increments the trav ID of the manager.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManIncrementTravId( Tim_Man_t * p )
-{
-    int i;
-    if ( p->nTravIds >= (1<<30)-1 )
-    {
-        p->nTravIds = 0;
-        for ( i = 0; i < p->nCis; i++ )
-            p->pCis[i].TravId = 0;
-        for ( i = 0; i < p->nCos; i++ )
-            p->pCos[i].TravId = 0;
-    }
-    assert( p->nTravIds < (1<<30)-1 );
-    p->nTravIds++;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Initializes arrival time of the PI.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManInitCiArrival( Tim_Man_t * p, int iCi, float Delay )
-{
-    assert( iCi < p->nCis );
-    p->pCis[iCi].timeArr = Delay;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Initializes required time of the PO.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManInitCoRequired( Tim_Man_t * p, int iCo, float Delay )
-{
-    assert( iCo < p->nCos );
-    p->pCos[iCo].timeReq = Delay;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Updates required time of the PO.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetCoArrival( Tim_Man_t * p, int iCo, float Delay )
-{
-    assert( iCo < p->nCos );
-    assert( !p->fUseTravId || p->pCos[iCo].TravId != p->nTravIds );
-    p->pCos[iCo].timeArr = Delay;
-    p->pCos[iCo].TravId = p->nTravIds;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Updates arrival time of the PI.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetCiRequired( Tim_Man_t * p, int iCi, float Delay )
-{
-    assert( iCi < p->nCis );
-    assert( !p->fUseTravId || p->pCis[iCi].TravId != p->nTravIds );
-    p->pCis[iCi].timeReq = Delay;
-    p->pCis[iCi].TravId = p->nTravIds;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Updates required time of the PO.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetCoRequired( Tim_Man_t * p, int iCo, float Delay )
-{
-    assert( iCo < p->nCos );
-    assert( !p->fUseTravId || p->pCos[iCo].TravId != p->nTravIds );
-    p->pCos[iCo].timeReq = Delay;
-    p->pCos[iCo].TravId = p->nTravIds;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Sets the correct required times for all POs.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetCiArrivalAll( Tim_Man_t * p, float Delay )
-{
-    Tim_Obj_t * pObj;
-    int i;
-    Tim_ManForEachCi( p, pObj, i )
-        Tim_ManInitCiArrival( p, i, Delay );
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Sets the correct required times for all POs.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManSetCoRequiredAll( Tim_Man_t * p, float Delay )
-{
-    Tim_Obj_t * pObj;
-    int i;
-    Tim_ManForEachCo( p, pObj, i )
-    {
-        Tim_ManSetCoRequired( p, i, Delay );
-//printf( "%d ", i );
-    }
-}
-
-
-/**Function*************************************************************
-
-  Synopsis    [Returns PI arrival time.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-float Tim_ManGetCiArrival( Tim_Man_t * p, int iCi )
-{
-    Tim_Box_t * pBox;
-    Tim_Obj_t * pObjThis, * pObj, * pObjRes;
-    float * pDelays, DelayBest;
-    int i, k;
-    // consider the already processed PI
-    pObjThis = Tim_ManCi( p, iCi );
-    if ( p->fUseTravId && pObjThis->TravId == p->nTravIds )
-        return pObjThis->timeArr;
-    pObjThis->TravId = p->nTravIds;
-    // consider the main PI
-    pBox = Tim_ManCiBox( p, iCi );
-    if ( pBox == NULL )
-        return pObjThis->timeArr;
-    // update box timing
-    pBox->TravId = p->nTravIds;
-    // get the arrival times of the inputs of the box (POs)
-    if ( p->fUseTravId )
-    Tim_ManBoxForEachInput( p, pBox, pObj, i )
-        if ( pObj->TravId != p->nTravIds )
-            printf( "Tim_ManGetCiArrival(): Input arrival times of the box are not up to date!\n" );
-    // compute the arrival times for each output of the box (PIs)
-    Tim_ManBoxForEachOutput( p, pBox, pObjRes, i )
-    {
-        pDelays = pBox->pDelayTable + i * pBox->nInputs;
-        DelayBest = -TIM_ETERNITY;
-        Tim_ManBoxForEachInput( p, pBox, pObj, k )
-            DelayBest = Abc_MaxInt( DelayBest, pObj->timeArr + pDelays[k] );
-        pObjRes->timeArr = DelayBest;
-        pObjRes->TravId = p->nTravIds;
-    }
-    return pObjThis->timeArr;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Returns PO required time.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-float Tim_ManGetCoRequired( Tim_Man_t * p, int iCo )
-{
-    Tim_Box_t * pBox;
-    Tim_Obj_t * pObjThis, * pObj, * pObjRes;
-    float * pDelays, DelayBest;
-    int i, k;
-    // consider the already processed PO
-    pObjThis = Tim_ManCo( p, iCo );
-    if ( p->fUseTravId && pObjThis->TravId == p->nTravIds )
-        return pObjThis->timeReq;
-    pObjThis->TravId = p->nTravIds;
-    // consider the main PO
-    pBox = Tim_ManCoBox( p, iCo );
-    if ( pBox == NULL )
-        return pObjThis->timeReq;
-    // update box timing
-    pBox->TravId = p->nTravIds;
-    // get the required times of the outputs of the box (PIs)
-    if ( p->fUseTravId )
-    Tim_ManBoxForEachOutput( p, pBox, pObj, i )
-        if ( pObj->TravId != p->nTravIds )
-            printf( "Tim_ManGetCoRequired(): Output required times of output %d the box %d are not up to date!\n", i, pBox->iBox );
-    // compute the required times for each input of the box (POs)
-    Tim_ManBoxForEachInput( p, pBox, pObjRes, i )
-    {
-        DelayBest = TIM_ETERNITY;
-        Tim_ManBoxForEachOutput( p, pBox, pObj, k )
-        {
-            pDelays = pBox->pDelayTable + k * pBox->nInputs;
-            DelayBest = Abc_MinFloat( DelayBest, pObj->timeReq - pDelays[i] );
-        }
-        pObjRes->timeReq = DelayBest;
-        pObjRes->TravId = p->nTravIds;
-    }
-    return pObjThis->timeReq;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Returns the box number for the given input.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Tim_ManBoxForCi( Tim_Man_t * p, int iCi )
-{
-    if ( iCi >= p->nCis )
-        return -1;
-    return p->pCis[iCi].iObj2Box;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Returns the box number for the given output.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Tim_ManBoxForCo( Tim_Man_t * p, int iCo )
-{
-    if ( iCo >= p->nCos )
-        return -1;
-    return p->pCos[iCo].iObj2Box;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Returns the first input of the box.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Tim_ManBoxInputFirst( Tim_Man_t * p, int iBox )
-{
-    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
-    return pBox->Inouts[0];
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Returns the first input of the box.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Tim_ManBoxOutputFirst( Tim_Man_t * p, int iBox )
-{
-    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
-    return pBox->Inouts[pBox->nInputs];
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Returns the first input of the box.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Tim_ManBoxInputNum( Tim_Man_t * p, int iBox )
-{
-    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
-    return pBox->nInputs;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Returns the first input of the box.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-int Tim_ManBoxOutputNum( Tim_Man_t * p, int iBox )
-{
-    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
-    return pBox->nOutputs;
-}
-
-/**Function*************************************************************
-
-  Synopsis    []
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Tim_ManChangeForAdders( Tim_Man_t * p )
-{
-    Tim_Box_t * pBox;
-    int i;
-    Tim_ManForEachBox( p, pBox, i )
-        pBox->pDelayTable[0] = 0.0;
-}
-
-
 ////////////////////////////////////////////////////////////////////////
 ///                       END OF FILE                                ///
 ////////////////////////////////////////////////////////////////////////
diff --git a/src/misc/tim/tim.h b/src/misc/tim/tim.h
index 9a7667d5..1eb1de78 100644
--- a/src/misc/tim/tim.h
+++ b/src/misc/tim/tim.h
@@ -4,7 +4,7 @@
 
   SystemName  [ABC: Logic synthesis and verification system.]
 
-  PackageName [A timing manager.]
+  PackageName [Hierarchy/timing manager.]
 
   Synopsis    [External declarations.]
 
@@ -30,10 +30,7 @@
 ///                         PARAMETERS                               ///
 ////////////////////////////////////////////////////////////////////////
 
-
-
 ABC_NAMESPACE_HEADER_START
- 
 
 ////////////////////////////////////////////////////////////////////////
 ///                         BASIC TYPES                              ///
@@ -59,43 +56,51 @@ typedef struct Tim_Man_t_           Tim_Man_t;
 ///                    FUNCTION DECLARATIONS                         ///
 ////////////////////////////////////////////////////////////////////////
 
-/*=== time.c ===========================================================*/
+/*=== timBox.c ===========================================================*/
+extern void            Tim_ManCreateBox( Tim_Man_t * p, int firstIn, int nIns, int firstOut, int nOuts, int iDelayTable );
+extern int             Tim_ManBoxForCi( Tim_Man_t * p, int iCo );
+extern int             Tim_ManBoxForCo( Tim_Man_t * p, int iCi );
+extern int             Tim_ManBoxInputFirst( Tim_Man_t * p, int iBox );
+extern int             Tim_ManBoxOutputFirst( Tim_Man_t * p, int iBox );
+extern int             Tim_ManBoxInputNum( Tim_Man_t * p, int iBox );
+extern int             Tim_ManBoxOutputNum( Tim_Man_t * p, int iBox );
+extern float *         Tim_ManBoxDelayTable( Tim_Man_t * p, int iBox );
+/*=== timDump.c ===========================================================*/
+extern Vec_Str_t *     Tim_ManSave( Tim_Man_t * p );
+extern Tim_Man_t *     Tim_ManLoad( Vec_Str_t * p );
+/*=== timMan.c ===========================================================*/
 extern Tim_Man_t *     Tim_ManStart( int nCis, int nCos );
-extern Tim_Man_t *     Tim_ManDup( Tim_Man_t * p, int fDiscrete );
-extern Tim_Man_t *     Tim_ManDupUnit( Tim_Man_t * p );
-extern Tim_Man_t *     Tim_ManDupApprox( Tim_Man_t * p );
+extern Tim_Man_t *     Tim_ManDup( Tim_Man_t * p, int fUnitDelay );
 extern void            Tim_ManStop( Tim_Man_t * p );
 extern void            Tim_ManStopP( Tim_Man_t ** p );
 extern void            Tim_ManPrint( Tim_Man_t * p );
+extern int             Tim_ManCiNum( Tim_Man_t * p );
+extern int             Tim_ManCoNum( Tim_Man_t * p );
+extern int             Tim_ManPiNum( Tim_Man_t * p );
+extern int             Tim_ManPoNum( Tim_Man_t * p );
+extern int             Tim_ManBoxNum( Tim_Man_t * p );
+extern int             Tim_ManDelayTableNum( Tim_Man_t * p );
+extern void            Tim_ManSetDelayTables( Tim_Man_t * p, Vec_Ptr_t * vDelayTables );
 extern void            Tim_ManTravIdDisable( Tim_Man_t * p );
 extern void            Tim_ManTravIdEnable( Tim_Man_t * p );
+/*=== timTime.c ===========================================================*/
+extern void            Tim_ManInitPiArrival( Tim_Man_t * p, int iPi, float Delay );
+extern void            Tim_ManInitPoRequired( Tim_Man_t * p, int iPo, float Delay );
+extern void            Tim_ManInitPiArrivalAll( Tim_Man_t * p, float Delay );
+extern void            Tim_ManInitPoRequiredAll( Tim_Man_t * p, float Delay );
+extern void            Tim_ManSetCoArrival( Tim_Man_t * p, int iCo, float Delay );
+extern void            Tim_ManSetCiRequired( Tim_Man_t * p, int iCi, float Delay );
+extern void            Tim_ManSetCoRequired( Tim_Man_t * p, int iCo, float Delay );
+extern float           Tim_ManGetCiArrival( Tim_Man_t * p, int iCi );
+extern float           Tim_ManGetCoRequired( Tim_Man_t * p, int iCo );
+/*=== timTrav.c ===========================================================*/
+extern void            Tim_ManIncrementTravId( Tim_Man_t * p );
 extern void            Tim_ManSetCurrentTravIdBoxInputs( Tim_Man_t * p, int iBox );
 extern void            Tim_ManSetCurrentTravIdBoxOutputs( Tim_Man_t * p, int iBox );
 extern void            Tim_ManSetPreviousTravIdBoxInputs( Tim_Man_t * p, int iBox );
 extern void            Tim_ManSetPreviousTravIdBoxOutputs( Tim_Man_t * p, int iBox );
 extern int             Tim_ManIsCiTravIdCurrent( Tim_Man_t * p, int iCi );
 extern int             Tim_ManIsCoTravIdCurrent( Tim_Man_t * p, int iCo );
-extern void            Tim_ManSetDelayTables( Tim_Man_t * p, Vec_Ptr_t * vDelayTables );
-extern void            Tim_ManCreateBox( Tim_Man_t * p, int * pIns, int nIns, int * pOuts, int nOuts, float * pDelayTable );
-extern void            Tim_ManCreateBoxFirst( Tim_Man_t * p, int firstIn, int nIns, int firstOut, int nOuts, float * pDelayTable );
-extern void            Tim_ManIncrementTravId( Tim_Man_t * p );
-extern void            Tim_ManInitCiArrival( Tim_Man_t * p, int iCi, float Delay );
-extern void            Tim_ManInitCoRequired( Tim_Man_t * p, int iCo, float Delay );
-extern void            Tim_ManSetCoArrival( Tim_Man_t * p, int iCo, float Delay );
-extern void            Tim_ManSetCiRequired( Tim_Man_t * p, int iCi, float Delay );
-extern void            Tim_ManSetCoRequired( Tim_Man_t * p, int iCo, float Delay );
-extern void            Tim_ManSetCiArrivalAll( Tim_Man_t * p, float Delay );
-extern void            Tim_ManSetCoRequiredAll( Tim_Man_t * p, float Delay );
-extern float           Tim_ManGetCiArrival( Tim_Man_t * p, int iCi );
-extern float           Tim_ManGetCoRequired( Tim_Man_t * p, int iCo );
-extern int             Tim_ManBoxForCi( Tim_Man_t * p, int iCo );
-extern int             Tim_ManBoxForCo( Tim_Man_t * p, int iCi );
-extern int             Tim_ManBoxInputFirst( Tim_Man_t * p, int iBox );
-extern int             Tim_ManBoxOutputFirst( Tim_Man_t * p, int iBox );
-extern int             Tim_ManBoxInputNum( Tim_Man_t * p, int iBox );
-extern int             Tim_ManBoxOutputNum( Tim_Man_t * p, int iBox );
-extern void            Tim_ManChangeForAdders( Tim_Man_t * p );
-
 
 
 ABC_NAMESPACE_HEADER_END
diff --git a/src/misc/tim/timBox.c b/src/misc/tim/timBox.c
new file mode 100644
index 00000000..65b0ae6e
--- /dev/null
+++ b/src/misc/tim/timBox.c
@@ -0,0 +1,204 @@
+/**CFile****************************************************************
+
+  FileName    [timBox.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Hierarchy/timing manager.]
+
+  Synopsis    [Manipulation of timing boxes.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - April 28, 2007.]
+
+  Revision    [$Id: timBox.c,v 1.00 2007/04/28 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "timInt.h"
+
+ABC_NAMESPACE_IMPL_START
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Creates the new timing box.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManCreateBox( Tim_Man_t * p, int firstIn, int nIns, int firstOut, int nOuts, int iDelayTable )
+{
+    Tim_Box_t * pBox;
+    int i;
+    if ( p->vBoxes == NULL )
+        p->vBoxes = Vec_PtrAlloc( 100 );
+    pBox = (Tim_Box_t *)Mem_FlexEntryFetch( p->pMemObj, sizeof(Tim_Box_t) + sizeof(int) * (nIns+nOuts) );
+    memset( pBox, 0, sizeof(Tim_Box_t) );
+    pBox->iBox = Vec_PtrSize( p->vBoxes );
+    Vec_PtrPush( p->vBoxes, pBox );
+    pBox->iDelayTable = iDelayTable;
+    pBox->nInputs  = nIns;
+    pBox->nOutputs = nOuts;
+    for ( i = 0; i < nIns; i++ )
+    {
+        assert( firstIn+i < p->nCos );
+        pBox->Inouts[i] = firstIn+i;
+        p->pCos[firstIn+i].iObj2Box = pBox->iBox;
+        p->pCos[firstIn+i].iObj2Num = i;
+    }
+    for ( i = 0; i < nOuts; i++ )
+    {
+        assert( firstOut+i < p->nCis );
+        pBox->Inouts[nIns+i] = firstOut+i;
+        p->pCis[firstOut+i].iObj2Box = pBox->iBox;
+        p->pCis[firstOut+i].iObj2Num = i;
+    }
+//    if ( pBox->iBox < 20 )
+//        printf( "%4d  %4d  %4d  %4d  \n", firstIn, nIns, firstOut, nOuts );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns the box number for the given input.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManBoxForCi( Tim_Man_t * p, int iCi )
+{
+    if ( iCi >= p->nCis )
+        return -1;
+    return p->pCis[iCi].iObj2Box;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns the box number for the given output.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManBoxForCo( Tim_Man_t * p, int iCo )
+{
+    if ( iCo >= p->nCos )
+        return -1;
+    return p->pCos[iCo].iObj2Box;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns the first input of the box.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManBoxInputFirst( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
+    return pBox->Inouts[0];
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns the first input of the box.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManBoxOutputFirst( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
+    return pBox->Inouts[pBox->nInputs];
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns the first input of the box.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManBoxInputNum( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
+    return pBox->nInputs;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns the first input of the box.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManBoxOutputNum( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
+    return pBox->nOutputs;
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+float * Tim_ManBoxDelayTable( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox = (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, iBox );
+    if ( pBox->iDelayTable < 0 )
+        return NULL;
+    return (float *)Vec_PtrEntry( p->vDelayTables, pBox->iDelayTable );
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/misc/tim/timDump.c b/src/misc/tim/timDump.c
new file mode 100644
index 00000000..031ef5fc
--- /dev/null
+++ b/src/misc/tim/timDump.c
@@ -0,0 +1,181 @@
+/**CFile****************************************************************
+
+  FileName    [timDump.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Hierarchy/timing manager.]
+
+  Synopsis    [Saving and loading the hierarchy timing manager.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - April 28, 2007.]
+
+  Revision    [$Id: timDump.c,v 1.00 2007/04/28 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "timInt.h"
+
+ABC_NAMESPACE_IMPL_START
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+#define TIM_DUMP_VER_NUM 1
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Transform the timing manager into the char stream.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Str_t * Tim_ManSave( Tim_Man_t * p )
+{
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObj;
+    Vec_Str_t * vStr;
+    float * pDelayTable;
+    int i, k, TableSize;
+    // create output stream
+    vStr = Vec_StrAlloc( 10000 );
+    // dump version number
+    Vec_StrPutI_ne( vStr, TIM_DUMP_VER_NUM );
+    // save CI/CO counts
+    Vec_StrPutI_ne( vStr, Tim_ManCiNum(p) );
+    Vec_StrPutI_ne( vStr, Tim_ManCoNum(p) );
+    // save PI/PO counts
+    Vec_StrPutI_ne( vStr, Tim_ManPiNum(p) );
+    Vec_StrPutI_ne( vStr, Tim_ManPoNum(p) );
+    // save number of boxes
+    Vec_StrPutI_ne( vStr, Tim_ManBoxNum(p) );
+    // for each box, save num_inputs, num_outputs, and delay table ID
+    Tim_ManForEachBox( p, pBox, i )
+    {
+        Vec_StrPutI_ne( vStr, Tim_ManBoxInputNum(p, pBox->iBox) );
+        Vec_StrPutI_ne( vStr, Tim_ManBoxOutputNum(p, pBox->iBox) );
+        Vec_StrPutI_ne( vStr, pBox->iDelayTable ); // can be -1 if delay table is not given
+    }
+    // save the number of delay tables
+    Vec_StrPutI_ne( vStr, Tim_ManDelayTableNum(p) );
+    // save the delay tables
+    Vec_PtrForEachEntry( float *, p->vDelayTables, pDelayTable, i )
+    {
+        assert( (int)pDelayTable[0] == i );
+        // save table ID and dimensions (inputs x outputs)
+        Vec_StrPutI_ne( vStr, (int)pDelayTable[0] );
+        Vec_StrPutI_ne( vStr, (int)pDelayTable[1] );
+        Vec_StrPutI_ne( vStr, (int)pDelayTable[2] );
+        // save table contents
+        TableSize = (int)pDelayTable[1] * (int)pDelayTable[2];
+        for ( k = 0; k < TableSize; k++ )
+            Vec_StrPutF( vStr, pDelayTable[k+3] );
+    }
+    // save PI arrival times
+    Tim_ManForEachPi( p, pObj, i )
+        Vec_StrPutF( vStr, Tim_ManGetCiArrival(p, pObj->Id) );
+    // save PO required times
+    Tim_ManForEachPo( p, pObj, i )
+        Vec_StrPutF( vStr, Tim_ManGetCoRequired(p, pObj->Id) );
+    return vStr;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Restores the timing manager from the char stream.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Tim_Man_t * Tim_ManLoad( Vec_Str_t * p )
+{
+    Tim_Man_t * pMan;
+    int VerNum, nCis, nCos, nPis, nPos;
+    int nBoxes, nBoxIns, nBoxOuts;
+    int TableId, nTables, TableSize, TableX, TableY;
+    int i, k, curPi, curPo, iStr = 0;
+    float * pDelayTable;
+    // get version number 
+    VerNum = Vec_StrGetI_ne( p, &iStr );
+    assert( VerNum == TIM_DUMP_VER_NUM );
+    // get the number of CIs/COs
+    nCis = Vec_StrGetI_ne( p, &iStr );
+    nCos = Vec_StrGetI_ne( p, &iStr );
+    // get the number of PIs/POs
+    nPis = Vec_StrGetI_ne( p, &iStr );
+    nPos = Vec_StrGetI_ne( p, &iStr );
+    // start the timing manager
+    pMan = Tim_ManStart( nCis, nCos );
+    // start boxes
+    nBoxes = Vec_StrGetI_ne( p, &iStr );
+    assert( pMan->vBoxes == NULL );
+    pMan->vBoxes = Vec_PtrAlloc( nBoxes );
+    // create boxes
+    curPi = nPis;
+    curPo = 0;
+    for ( i = 0; i < nBoxes; i++ )
+    {
+        nBoxIns  = Vec_StrGetI_ne( p, &iStr );
+        nBoxOuts = Vec_StrGetI_ne( p, &iStr );
+        TableId  = Vec_StrGetI_ne( p, &iStr );
+        Tim_ManCreateBox( pMan, curPo, nBoxIns, curPi, nBoxOuts, TableId );
+        curPi += nBoxOuts;
+        curPo += nBoxIns;
+    }
+    curPo += nPos;
+    assert( curPi == nCis );
+    assert( curPo == nCos );
+    // create delay tables
+    nTables = Vec_StrGetI_ne( p, &iStr );
+    assert( pMan->vDelayTables == NULL );
+    pMan->vDelayTables = Vec_PtrAlloc( nTables );
+    // read delay tables
+    assert( Vec_PtrSize(pMan->vDelayTables) == 0 );
+    for ( i = 0; i < nTables; i++ )
+    {
+        // read table ID and dimensions
+        TableId = Vec_StrGetI_ne( p, &iStr );
+        TableX  = Vec_StrGetI_ne( p, &iStr );
+        TableY  = Vec_StrGetI_ne( p, &iStr );
+        assert( TableId == i );
+        // create new table
+        TableSize = TableX * TableY;
+        pDelayTable = ABC_ALLOC( float, TableSize + 3 );
+        pDelayTable[0] = TableId;
+        pDelayTable[1] = TableX;
+        pDelayTable[2] = TableY;
+        // read table contents
+        for ( k = 0; k < TableSize; k++ )
+            pDelayTable[k+3] = Vec_StrGetF( p, &iStr );
+        assert( Vec_PtrSize(pMan->vDelayTables) == TableId );
+        Vec_PtrPush( pMan->vDelayTables, pDelayTable );
+    }
+    assert( Vec_PtrSize(pMan->vDelayTables) == nTables );
+//    Tim_ManPrint( pMan );
+    return pMan;
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/misc/tim/timInt.h b/src/misc/tim/timInt.h
new file mode 100644
index 00000000..9d8b7389
--- /dev/null
+++ b/src/misc/tim/timInt.h
@@ -0,0 +1,151 @@
+/**CFile****************************************************************
+
+  FileName    [timInt.h]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Hierarchy/timing manager.]
+
+  Synopsis    [Internal declarations.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - April 28, 2007.]
+
+  Revision    [$Id: timInt.h,v 1.00 2007/04/28 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#ifndef ABC__aig__tim__timInt_h
+#define ABC__aig__tim__timInt_h
+
+
+////////////////////////////////////////////////////////////////////////
+///                          INCLUDES                                ///
+////////////////////////////////////////////////////////////////////////
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+#include "misc/vec/vec.h"
+#include "misc/mem/mem.h"
+#include "tim.h"
+
+////////////////////////////////////////////////////////////////////////
+///                         PARAMETERS                               ///
+////////////////////////////////////////////////////////////////////////
+
+ABC_NAMESPACE_HEADER_START
+
+////////////////////////////////////////////////////////////////////////
+///                         BASIC TYPES                              ///
+////////////////////////////////////////////////////////////////////////
+
+typedef struct Tim_Box_t_           Tim_Box_t;
+typedef struct Tim_Obj_t_           Tim_Obj_t;
+
+// timing manager
+struct Tim_Man_t_
+{
+    Vec_Ptr_t *      vBoxes;         // the timing boxes
+    Vec_Ptr_t *      vDelayTables;   // pointers to the delay tables
+    Mem_Flex_t *     pMemObj;        // memory manager for boxes
+    int              nTravIds;       // traversal ID of the manager
+    int              fUseTravId;     // enables the use of traversal ID
+    int              nCis;           // the number of PIs
+    int              nCos;           // the number of POs
+    Tim_Obj_t *      pCis;           // timing info for the PIs
+    Tim_Obj_t *      pCos;           // timing info for the POs
+};
+
+// timing box
+struct Tim_Box_t_
+{
+    int              iBox;           // the unique ID of this box
+    int              TravId;         // traversal ID of this box
+    int              nInputs;        // the number of box inputs (POs)
+    int              nOutputs;       // the number of box outputs (PIs)
+    int              iDelayTable;    // index of the delay table
+    int              Inouts[0];      // the int numbers of PIs and POs
+};
+
+// timing object
+struct Tim_Obj_t_
+{
+    int              Id;             // the ID of this object
+    int              TravId;         // traversal ID of this object
+    int              iObj2Box;       // mapping of the object into its box
+    int              iObj2Num;       // mapping of the object into its number in the box
+    float            timeArr;        // arrival time of the object
+    float            timeReq;        // required time of the object
+};
+
+/* 
+    A delay table is a one-dimensional array of floats whose size is: 3 + nInputs * nOutputs.
+    The first entry is the delay table ID used by the boxes to refer to the table.
+    The second and third entris are nInputs and nOutputs.
+    The following entries list the delay numbers for per output, 
+    that is, the first nInputs entries give delay of the first output, etc.
+*/   
+
+////////////////////////////////////////////////////////////////////////
+///                      MACRO DEFINITIONS                           ///
+////////////////////////////////////////////////////////////////////////
+
+static inline Tim_Obj_t * Tim_ManCi( Tim_Man_t * p, int i )                           { assert( i < p->nCis ); return p->pCis + i;      }
+static inline Tim_Obj_t * Tim_ManCo( Tim_Man_t * p, int i )                           { assert( i < p->nCos ); return p->pCos + i;      }
+static inline Tim_Box_t * Tim_ManBox( Tim_Man_t * p, int i )                          { return (Tim_Box_t *)Vec_PtrEntry(p->vBoxes, i); }
+
+static inline Tim_Box_t * Tim_ManCiBox( Tim_Man_t * p, int i )                        { return Tim_ManCi(p,i)->iObj2Box < 0 ? NULL : (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, Tim_ManCi(p,i)->iObj2Box ); }
+static inline Tim_Box_t * Tim_ManCoBox( Tim_Man_t * p, int i )                        { return Tim_ManCo(p,i)->iObj2Box < 0 ? NULL : (Tim_Box_t *)Vec_PtrEntry( p->vBoxes, Tim_ManCo(p,i)->iObj2Box ); }
+
+static inline Tim_Obj_t * Tim_ManBoxInput( Tim_Man_t * p, Tim_Box_t * pBox, int i )   { assert( i < pBox->nInputs  ); return p->pCos + pBox->Inouts[i];               }
+static inline Tim_Obj_t * Tim_ManBoxOutput( Tim_Man_t * p, Tim_Box_t * pBox, int i )  { assert( i < pBox->nOutputs ); return p->pCis + pBox->Inouts[pBox->nInputs+i]; }
+
+////////////////////////////////////////////////////////////////////////
+///                             ITERATORS                            ///
+////////////////////////////////////////////////////////////////////////
+
+#define Tim_ManForEachCi( p, pObj, i )                                  \
+    for ( i = 0; (i < (p)->nCis) && ((pObj) = (p)->pCis + i); i++ )
+#define Tim_ManForEachCo( p, pObj, i )                                  \
+    for ( i = 0; (i < (p)->nCos) && ((pObj) = (p)->pCos + i); i++ )
+
+#define Tim_ManForEachPi( p, pObj, i )                                  \
+    Tim_ManForEachCi( p, pObj, i ) if ( pObj->iObj2Box >= 0 ) {} else 
+#define Tim_ManForEachPo( p, pObj, i )                                  \
+    Tim_ManForEachCo( p, pObj, i ) if ( pObj->iObj2Box >= 0 ) {} else 
+
+#define Tim_ManForEachBox( p, pBox, i )                                 \
+    Vec_PtrForEachEntry( Tim_Box_t *, p->vBoxes, pBox, i )
+
+#define Tim_ManBoxForEachInput( p, pBox, pObj, i )                      \
+    for ( i = 0; (i < (pBox)->nInputs) && ((pObj) = Tim_ManBoxInput(p, pBox, i)); i++ )
+#define Tim_ManBoxForEachOutput( p, pBox, pObj, i )                     \
+    for ( i = 0; (i < (pBox)->nOutputs) && ((pObj) = Tim_ManBoxOutput(p, pBox, i)); i++ )
+
+////////////////////////////////////////////////////////////////////////
+///                     SEQUENTIAL ITERATORS                         ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                    FUNCTION DECLARATIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/*=== time.c ===========================================================*/
+
+
+ABC_NAMESPACE_HEADER_END
+
+
+
+#endif
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
diff --git a/src/misc/tim/timMan.c b/src/misc/tim/timMan.c
new file mode 100644
index 00000000..5340ad9e
--- /dev/null
+++ b/src/misc/tim/timMan.c
@@ -0,0 +1,344 @@
+/**CFile****************************************************************
+
+  FileName    [timMan.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Hierarchy/timing manager.]
+
+  Synopsis    [Manipulation of manager data-structure.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - April 28, 2007.]
+
+  Revision    [$Id: timMan.c,v 1.00 2007/04/28 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "timInt.h"
+
+ABC_NAMESPACE_IMPL_START
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Starts the timing manager.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Tim_Man_t * Tim_ManStart( int nCis, int nCos )
+{
+    Tim_Man_t * p;
+    Tim_Obj_t * pObj;
+    int i;
+    p = ABC_ALLOC( Tim_Man_t, 1 );
+    memset( p, 0, sizeof(Tim_Man_t) );
+    p->pMemObj = Mem_FlexStart();
+    p->nCis = nCis;
+    p->nCos = nCos;
+    p->pCis = ABC_ALLOC( Tim_Obj_t, nCis );
+    memset( p->pCis, 0, sizeof(Tim_Obj_t) * nCis );
+    p->pCos = ABC_ALLOC( Tim_Obj_t, nCos );
+    memset( p->pCos, 0, sizeof(Tim_Obj_t) * nCos );
+    Tim_ManForEachCi( p, pObj, i )
+    {
+        pObj->Id = i;
+        pObj->iObj2Box = pObj->iObj2Num = -1;
+        pObj->timeReq = TIM_ETERNITY;
+    }
+    Tim_ManForEachCo( p, pObj, i )
+    {
+        pObj->Id = i;
+        pObj->iObj2Box = pObj->iObj2Num = -1;
+        pObj->timeReq = TIM_ETERNITY;
+    }
+    p->fUseTravId = 1;
+    return p;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Duplicates the timing manager.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Tim_Man_t * Tim_ManDup( Tim_Man_t * p, int fUnitDelay )
+{
+    Tim_Man_t * pNew;
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObj;
+    float * pDelayTable, * pDelayTableNew;
+    int i, k, nInputs, nOutputs;
+    // create new manager
+    pNew = Tim_ManStart( p->nCis, p->nCos );
+    // copy box connectivity information
+    memcpy( pNew->pCis, p->pCis, sizeof(Tim_Obj_t) * p->nCis );
+    memcpy( pNew->pCos, p->pCos, sizeof(Tim_Obj_t) * p->nCos );
+    // clear traversal IDs
+    Tim_ManForEachCi( p, pObj, i )
+        pObj->TravId = 0;
+    Tim_ManForEachCo( p, pObj, i )
+        pObj->TravId = 0;
+    if ( fUnitDelay )
+    {
+        // discretize PI arrival times
+//        Tim_ManForEachPi( pNew, pObj, k )
+//          pObj->timeArr = (int)pObj->timeArr;
+        // discretize PO required times
+//        Tim_ManForEachPo( pNew, pObj, k )
+//          pObj->timeReq = 1 + (int)pObj->timeReq;
+        // clear PI arrival and PO required
+        Tim_ManInitPiArrivalAll( p, 0.0 );
+        Tim_ManInitPoRequiredAll( p, (float)TIM_ETERNITY );
+    }
+    // duplicate delay tables
+    pNew->vDelayTables = Vec_PtrAlloc( Vec_PtrSize(p->vDelayTables) );
+    Vec_PtrForEachEntry( float *, p->vDelayTables, pDelayTable, i )
+    {
+        assert( i == (int)pDelayTable[0] );
+        nInputs   = (int)pDelayTable[1];
+        nOutputs  = (int)pDelayTable[2];
+        pDelayTableNew = ABC_ALLOC( float, 3 + nInputs * nOutputs );
+        pDelayTableNew[0] = (int)pDelayTable[0];
+        pDelayTableNew[1] = (int)pDelayTable[1];
+        pDelayTableNew[2] = (int)pDelayTable[2];
+        for ( k = 0; k < nInputs * nOutputs; k++ )
+            pDelayTableNew[3+k] = fUnitDelay ? 1.0 : pDelayTable[3+k];
+        assert( (int)pDelayTableNew[0] == Vec_PtrSize(pNew->vDelayTables) );
+        Vec_PtrPush( pNew->vDelayTables, pDelayTableNew );
+    }
+    // duplicate boxes
+    Tim_ManForEachBox( p, pBox, i )
+       Tim_ManCreateBox( pNew, pBox->Inouts[0], pBox->nInputs, 
+            pBox->Inouts[pBox->nInputs], pBox->nOutputs, pBox->iDelayTable );
+    return pNew;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Stops the timing manager.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManStop( Tim_Man_t * p )
+{
+    float * pTable;
+    int i;
+    if ( p->vDelayTables )
+    {
+        Vec_PtrForEachEntry( float *, p->vDelayTables, pTable, i )
+            ABC_FREE( pTable );
+        Vec_PtrFree( p->vDelayTables );
+    }
+    Vec_PtrFree( p->vBoxes );
+    Mem_FlexStop( p->pMemObj, 0 );
+    ABC_FREE( p->pCis );
+    ABC_FREE( p->pCos );
+    ABC_FREE( p );
+}
+void Tim_ManStopP( Tim_Man_t ** p )
+{
+    if ( *p == NULL )
+        return;
+    Tim_ManStop( *p );
+    *p = NULL;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Prints the timing manager.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManPrint( Tim_Man_t * p )
+{
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObj, * pPrev;
+    float * pTable;
+    int i, k;
+    printf( "TIMING INFORMATION:\n" );
+
+    // print CI info
+    pPrev = p->pCis;
+    Tim_ManForEachPi( p, pObj, i )
+        if ( pPrev->timeArr != pObj->timeArr || pPrev->timeReq != pObj->timeReq )
+            break;
+    if ( i == Tim_ManCiNum(p) )
+        printf( "All PIs :  arr = %5.3f  req = %5.3f\n", pPrev->timeArr, pPrev->timeReq );
+    else
+        Tim_ManForEachPi( p, pObj, i )
+            printf( "PI%5d :  arr = %5.3f  req = %5.3f\n", i, pObj->timeArr, pObj->timeReq );
+
+    // print CO info
+    pPrev = p->pCos;
+    Tim_ManForEachPo( p, pObj, i )
+        if ( pPrev->timeArr != pObj->timeArr || pPrev->timeReq != pObj->timeReq )
+            break;
+    if ( i == Tim_ManCoNum(p) )
+        printf( "All POs :  arr = %5.3f  req = %5.3f\n", pPrev->timeArr, pPrev->timeReq );
+    else
+        Tim_ManForEachPo( p, pObj, i )
+            printf( "PO%5d :  arr = %5.3f  req = %5.3f\n", i, pObj->timeArr, pObj->timeReq );
+
+    // print box info
+    Tim_ManForEachBox( p, pBox, i )
+    {
+        printf( "*** Box %3d :  Ins = %d. Outs = %d.\n", i, pBox->nInputs, pBox->nOutputs );
+        printf( "Delay table:\n" );
+        pTable = Tim_ManBoxDelayTable( p, pBox->iBox );
+        for ( i = 0; i < pBox->nOutputs; i++, printf( "\n" ) )
+            for ( k = 0; k < pBox->nInputs; k++ )
+                if ( pTable[3+i*pBox->nInputs+k] == -ABC_INFINITY )
+                    printf( "%5s", "-" );
+                else
+                    printf( "%5.0f", pTable[3+i*pBox->nInputs+k] );
+        printf( "\n" );
+
+        // print box inputs
+        pPrev = Tim_ManBoxInput( p, pBox, 0 );
+        Tim_ManBoxForEachInput( p, pBox, pObj, i )
+            if ( pPrev->timeArr != pObj->timeArr || pPrev->timeReq != pObj->timeReq )
+                break;
+        if ( i == Tim_ManBoxInputNum(p, pBox->iBox) )
+            printf( "Box inputs  :  arr = %5.3f  req = %5.3f\n", pPrev->timeArr, pPrev->timeReq );
+        else
+            Tim_ManBoxForEachInput( p, pBox, pObj, i )
+                printf( "box-inp%3d :  arr = %5.3f  req = %5.3f\n", i, pObj->timeArr, pObj->timeReq );
+
+        // print box outputs
+        pPrev = Tim_ManBoxOutput( p, pBox, 0 );
+        Tim_ManBoxForEachOutput( p, pBox, pObj, i )
+            if ( pPrev->timeArr != pObj->timeArr || pPrev->timeReq != pObj->timeReq )
+                break;
+        if ( i == Tim_ManBoxOutputNum(p, pBox->iBox) )
+            printf( "Box outputs :  arr = %5.3f  req = %5.3f\n", pPrev->timeArr, pPrev->timeReq );
+        else
+            Tim_ManBoxForEachOutput( p, pBox, pObj, i )
+                printf( "box-out%3d :  arr = %5.3f  req = %5.3f\n", i, pObj->timeArr, pObj->timeReq );
+    }
+    printf( "\n" );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Read parameters.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManCiNum( Tim_Man_t * p )
+{
+    return p->nCis;
+}
+int Tim_ManCoNum( Tim_Man_t * p )
+{
+    return p->nCos;
+}
+int Tim_ManPiNum( Tim_Man_t * p )
+{
+    return Tim_ManBoxOutputFirst(p, 0);
+}
+int Tim_ManPoNum( Tim_Man_t * p )
+{
+    int iLastBoxId = Tim_ManBoxNum(p) - 1;
+    return Tim_ManCoNum(p) - (Tim_ManBoxInputFirst(p, iLastBoxId) + Tim_ManBoxInputNum(p, iLastBoxId));
+}
+int Tim_ManBoxNum( Tim_Man_t * p )
+{
+    return Vec_PtrSize(p->vBoxes);
+}
+int Tim_ManDelayTableNum( Tim_Man_t * p )
+{
+    return Vec_PtrSize(p->vDelayTables);
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Sets the vector of timing tables associated with the manager.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManSetDelayTables( Tim_Man_t * p, Vec_Ptr_t * vDelayTables )
+{
+    assert( p->vDelayTables == NULL );
+    p->vDelayTables = vDelayTables;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Disables the use of the traversal ID.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManTravIdDisable( Tim_Man_t * p )
+{
+    p->fUseTravId = 0;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Enables the use of the traversal ID.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManTravIdEnable( Tim_Man_t * p )
+{
+    p->fUseTravId = 1;
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/misc/tim/timTime.c b/src/misc/tim/timTime.c
new file mode 100644
index 00000000..ddec4c62
--- /dev/null
+++ b/src/misc/tim/timTime.c
@@ -0,0 +1,265 @@
+/**CFile****************************************************************
+
+  FileName    [timTime.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Hierarchy/timing manager.]
+
+  Synopsis    [Setting and resetting timing information of the boxes.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - April 28, 2007.]
+
+  Revision    [$Id: timTime.c,v 1.00 2007/04/28 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "timInt.h"
+
+ABC_NAMESPACE_IMPL_START
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Initializes arrival time of the PI.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManInitPiArrival( Tim_Man_t * p, int iPi, float Delay )
+{
+    assert( iPi < p->nCis );
+    p->pCis[iPi].timeArr = Delay;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Initializes required time of the PO.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManInitPoRequired( Tim_Man_t * p, int iPo, float Delay )
+{
+    assert( iPo < p->nCos );
+    p->pCos[iPo].timeReq = Delay;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Sets arrival times of all PIs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManInitPiArrivalAll( Tim_Man_t * p, float Delay )
+{
+    Tim_Obj_t * pObj;
+    int i;
+    Tim_ManForEachPi( p, pObj, i )
+        Tim_ManInitPiArrival( p, i, Delay );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Sets required times of all POs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManInitPoRequiredAll( Tim_Man_t * p, float Delay )
+{
+    Tim_Obj_t * pObj;
+    int i;
+    Tim_ManForEachPo( p, pObj, i )
+        Tim_ManSetCoRequired( p, i, Delay );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Updates arrival time of the CO.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManSetCoArrival( Tim_Man_t * p, int iCo, float Delay )
+{
+    assert( iCo < p->nCos );
+    assert( !p->fUseTravId || p->pCos[iCo].TravId != p->nTravIds );
+    p->pCos[iCo].timeArr = Delay;
+    p->pCos[iCo].TravId = p->nTravIds;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Updates required time of the CI.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManSetCiRequired( Tim_Man_t * p, int iCi, float Delay )
+{
+    assert( iCi < p->nCis );
+    assert( !p->fUseTravId || p->pCis[iCi].TravId != p->nTravIds );
+    p->pCis[iCi].timeReq = Delay;
+    p->pCis[iCi].TravId = p->nTravIds;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Updates required time of the CO.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManSetCoRequired( Tim_Man_t * p, int iCo, float Delay )
+{
+    assert( iCo < p->nCos );
+    assert( !p->fUseTravId || p->pCos[iCo].TravId != p->nTravIds );
+    p->pCos[iCo].timeReq = Delay;
+    p->pCos[iCo].TravId = p->nTravIds;
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Returns CO arrival time.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+float Tim_ManGetCiArrival( Tim_Man_t * p, int iCi )
+{
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObjThis, * pObj, * pObjRes;
+    float * pTable, * pDelays, DelayBest;
+    int i, k;
+    // consider the already processed PI
+    pObjThis = Tim_ManCi( p, iCi );
+    if ( p->fUseTravId && pObjThis->TravId == p->nTravIds )
+        return pObjThis->timeArr;
+    pObjThis->TravId = p->nTravIds;
+    // consider the main PI
+    pBox = Tim_ManCiBox( p, iCi );
+    if ( pBox == NULL )
+        return pObjThis->timeArr;
+    // update box timing
+    pBox->TravId = p->nTravIds;
+    // get the arrival times of the inputs of the box (POs)
+    if ( p->fUseTravId )
+    Tim_ManBoxForEachInput( p, pBox, pObj, i )
+        if ( pObj->TravId != p->nTravIds )
+            printf( "Tim_ManGetCiArrival(): Input arrival times of the box are not up to date!\n" );
+    // compute the arrival times for each output of the box (PIs)
+    pTable = Tim_ManBoxDelayTable( p, pBox->iBox );
+    Tim_ManBoxForEachOutput( p, pBox, pObjRes, i )
+    {
+        pDelays = pTable + 3 + i * pBox->nInputs;
+        DelayBest = -TIM_ETERNITY;
+        Tim_ManBoxForEachInput( p, pBox, pObj, k )
+            DelayBest = Abc_MaxInt( DelayBest, pObj->timeArr + pDelays[k] );
+        pObjRes->timeArr = DelayBest;
+        pObjRes->TravId = p->nTravIds;
+    }
+    return pObjThis->timeArr;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns CO required time.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+float Tim_ManGetCoRequired( Tim_Man_t * p, int iCo )
+{
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObjThis, * pObj, * pObjRes;
+    float * pTable, * pDelays, DelayBest;
+    int i, k;
+    // consider the already processed PO
+    pObjThis = Tim_ManCo( p, iCo );
+    if ( p->fUseTravId && pObjThis->TravId == p->nTravIds )
+        return pObjThis->timeReq;
+    pObjThis->TravId = p->nTravIds;
+    // consider the main PO
+    pBox = Tim_ManCoBox( p, iCo );
+    if ( pBox == NULL )
+        return pObjThis->timeReq;
+    // update box timing
+    pBox->TravId = p->nTravIds;
+    // get the required times of the outputs of the box (PIs)
+    if ( p->fUseTravId )
+    Tim_ManBoxForEachOutput( p, pBox, pObj, i )
+        if ( pObj->TravId != p->nTravIds )
+            printf( "Tim_ManGetCoRequired(): Output required times of output %d the box %d are not up to date!\n", i, pBox->iBox );
+    // compute the required times for each input of the box (POs)
+    pTable = Tim_ManBoxDelayTable( p, pBox->iBox );
+    Tim_ManBoxForEachInput( p, pBox, pObjRes, i )
+    {
+        DelayBest = TIM_ETERNITY;
+        Tim_ManBoxForEachOutput( p, pBox, pObj, k )
+        {
+            pDelays = pTable + 3 + k * pBox->nInputs;
+            DelayBest = Abc_MinFloat( DelayBest, pObj->timeReq - pDelays[i] );
+        }
+        pObjRes->timeReq = DelayBest;
+        pObjRes->TravId = p->nTravIds;
+    }
+    return pObjThis->timeReq;
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/misc/tim/timTrav.c b/src/misc/tim/timTrav.c
new file mode 100644
index 00000000..4c3f64ad
--- /dev/null
+++ b/src/misc/tim/timTrav.c
@@ -0,0 +1,185 @@
+/**CFile****************************************************************
+
+  FileName    [timTrav.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Hierarchy/timing manager.]
+
+  Synopsis    [Manipulation of traversal IDs.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - April 28, 2007.]
+
+  Revision    [$Id: timTrav.c,v 1.00 2007/04/28 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "timInt.h"
+
+ABC_NAMESPACE_IMPL_START
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Increments the trav ID of the manager.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManIncrementTravId( Tim_Man_t * p )
+{
+    int i;
+    if ( p->nTravIds >= (1<<30)-1 )
+    {
+        p->nTravIds = 0;
+        for ( i = 0; i < p->nCis; i++ )
+            p->pCis[i].TravId = 0;
+        for ( i = 0; i < p->nCos; i++ )
+            p->pCos[i].TravId = 0;
+    }
+    assert( p->nTravIds < (1<<30)-1 );
+    p->nTravIds++;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Label box inputs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManSetCurrentTravIdBoxInputs( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObj;
+    int i;
+    pBox = Tim_ManBox( p, iBox );
+    Tim_ManBoxForEachInput( p, pBox, pObj, i )
+        pObj->TravId = p->nTravIds;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Label box outputs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManSetCurrentTravIdBoxOutputs( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObj;
+    int i;
+    pBox = Tim_ManBox( p, iBox );
+    Tim_ManBoxForEachOutput( p, pBox, pObj, i )
+        pObj->TravId = p->nTravIds;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Label box inputs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManSetPreviousTravIdBoxInputs( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObj;
+    int i;
+    pBox = Tim_ManBox( p, iBox );
+    Tim_ManBoxForEachInput( p, pBox, pObj, i )
+        pObj->TravId = p->nTravIds - 1;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Label box outputs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Tim_ManSetPreviousTravIdBoxOutputs( Tim_Man_t * p, int iBox )
+{
+    Tim_Box_t * pBox;
+    Tim_Obj_t * pObj;
+    int i;
+    pBox = Tim_ManBox( p, iBox );
+    Tim_ManBoxForEachOutput( p, pBox, pObj, i )
+        pObj->TravId = p->nTravIds - 1;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Updates required time of the CI.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManIsCiTravIdCurrent( Tim_Man_t * p, int iCi )
+{
+    assert( iCi < p->nCis );
+    assert( p->fUseTravId );
+    return p->pCis[iCi].TravId == p->nTravIds;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Updates required time of the CO.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Tim_ManIsCoTravIdCurrent( Tim_Man_t * p, int iCo )
+{
+    assert( iCo < p->nCos );
+    assert( p->fUseTravId );
+    return p->pCos[iCo].TravId == p->nTravIds;
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/misc/vec/vecStr.h b/src/misc/vec/vecStr.h
index d64fea65..238fe451 100644
--- a/src/misc/vec/vecStr.h
+++ b/src/misc/vec/vecStr.h
@@ -638,6 +638,28 @@ static inline void Vec_StrReverseOrder( Vec_Str_t * p )
 
 /**Function*************************************************************
 
+  Synopsis    [Compares two strings.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int Vec_StrEqual( Vec_Str_t * p1, Vec_Str_t * p2 ) 
+{
+    int i;
+    if ( p1->nSize != p2->nSize )
+        return 0;
+    for ( i = 0; i < p1->nSize; i++ )
+        if ( p1->pArray[i] != p2->pArray[i] )
+            return 0;
+    return 1;
+}
+
+/**Function*************************************************************
+
   Synopsis    [Comparison procedure for two clauses.]
 
   Description []
diff --git a/src/opt/nwk/nwkDfs.c b/src/opt/nwk/nwkDfs.c
index 59752c59..c230787d 100644
--- a/src/opt/nwk/nwkDfs.c
+++ b/src/opt/nwk/nwkDfs.c
@@ -110,7 +110,7 @@ int Nwk_ManLevelBackup( Nwk_Man_t * pNtk )
         Nwk_ObjSetLevel( pObj, 0 );
     // perform level computation
     LevelMax = 0;
-    pManTimeUnit = pNtk->pManTime ? Tim_ManDupUnit( pNtk->pManTime ) : NULL;
+    pManTimeUnit = pNtk->pManTime ? Tim_ManDup( pNtk->pManTime, 1 ) : NULL;
     if ( pManTimeUnit )
         Tim_ManIncrementTravId( pManTimeUnit );
     Nwk_ManForEachObj( pNtk, pObj, i )
diff --git a/src/opt/nwk/nwkTiming.c b/src/opt/nwk/nwkTiming.c
index 9419c175..d62696b1 100644
--- a/src/opt/nwk/nwkTiming.c
+++ b/src/opt/nwk/nwkTiming.c
@@ -373,7 +373,7 @@ float Nwk_ManDelayTraceLut( Nwk_Man_t * pNtk )
     if ( pNtk->pManTime )
     {
         Tim_ManIncrementTravId( pNtk->pManTime );
-        Tim_ManSetCoRequiredAll( pNtk->pManTime, tArrival );
+        Tim_ManInitPoRequiredAll( pNtk->pManTime, tArrival );
     }
     else
     {