Version abc60412

4 files changed, 540 insertions, 198 deletions

diff --git a/src/base/io/io.c b/src/base/io/io.c
index 0aa5e415..614fa812 100644
--- a/src/base/io/io.c
+++ b/src/base/io/io.c
@@ -912,7 +912,7 @@ int IoCommandWriteBlif( Abc_Frame_t * pAbc, int argc, char **argv )
         return 0;
     }
     Io_WriteBlifLogic( pNtk, FileName, fWriteLatches );
-//    Io_WriteBlif( pNtk, FileName, fWriteLatches );
+//    Io_WriteBlifNetlist( pNtk, FileName, fWriteLatches );
     return 0;
 
 usage:
diff --git a/src/base/io/io.h b/src/base/io/io.h
index a9a61040..b408293e 100644
--- a/src/base/io/io.h
+++ b/src/base/io/io.h
@@ -77,8 +77,8 @@ extern FILE *             Io_FileOpen( const char * FileName, const char * PathV
 /*=== abcWriteBaf.c ==========================================================*/
 extern void               Io_WriteBaf( Abc_Ntk_t * pNtk, char * pFileName );
 /*=== abcWriteBlif.c ==========================================================*/
-extern void               Io_WriteBlif( Abc_Ntk_t * pNtk, char * pFileName, int fWriteLatches );
 extern void               Io_WriteBlifLogic( Abc_Ntk_t * pNtk, char * pFileName, int fWriteLatches );
+extern void               Io_WriteBlifNetlist( Abc_Ntk_t * pNtk, char * pFileName, int fWriteLatches );
 extern void               Io_WriteTimingInfo( FILE * pFile, Abc_Ntk_t * pNtk );
 /*=== abcWriteBench.c ==========================================================*/
 extern int                Io_WriteBench( Abc_Ntk_t * pNtk, char * FileName );
diff --git a/src/base/io/ioReadBlif.c b/src/base/io/ioReadBlif.c
index 39b85a10..9d74a782 100644
--- a/src/base/io/ioReadBlif.c
+++ b/src/base/io/ioReadBlif.c
@@ -33,11 +33,10 @@ struct Io_ReadBlif_t_
     char *               pFileName;    // the name of the file
     Extra_FileReader_t * pReader;      // the input file reader
     // current processing info
-    Abc_Ntk_t *          pNtk;         // the primary network
-    Abc_Ntk_t *          pNtkExdc;     // the exdc network
-    int                  fParsingExdc; // this flag is on, when we are parsing EXDC network
+    Abc_Ntk_t *          pNtkCur;      // the primary network
     int                  LineCur;      // the line currently parsed
     // temporary storage for tokens
+    Vec_Ptr_t *          vTokens;      // the current tokens
     Vec_Ptr_t *          vNewTokens;   // the temporary storage for the tokens
     Vec_Str_t *          vCubes;       // the temporary storage for the tokens
     // the error message
@@ -49,16 +48,19 @@ static Io_ReadBlif_t * Io_ReadBlifFile( char * pFileName );
 static void Io_ReadBlifFree( Io_ReadBlif_t * p );
 static void Io_ReadBlifPrintErrorMessage( Io_ReadBlif_t * p );
 static Vec_Ptr_t * Io_ReadBlifGetTokens( Io_ReadBlif_t * p );
-static Abc_Ntk_t * Io_ReadBlifNetwork( Io_ReadBlif_t * p );
 static char * Io_ReadBlifCleanName( char * pName );
 
+static Abc_Ntk_t * Io_ReadBlifNetwork( Io_ReadBlif_t * p );
+static Abc_Ntk_t * Io_ReadBlifNetworkOne( Io_ReadBlif_t * p );
 static int Io_ReadBlifNetworkInputs( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens );
 static int Io_ReadBlifNetworkOutputs( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens );
 static int Io_ReadBlifNetworkLatch( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens );
 static int Io_ReadBlifNetworkNames( Io_ReadBlif_t * p, Vec_Ptr_t ** pvTokens );
 static int Io_ReadBlifNetworkGate( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens );
+static int Io_ReadBlifNetworkSubcircuit( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens );
 static int Io_ReadBlifNetworkInputArrival( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens );
 static int Io_ReadBlifNetworkDefaultInputArrival( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens );
+static int Io_ReadBlifNetworkConnectBoxes( Io_ReadBlif_t * p, Abc_Ntk_t * pNtkMaster );
 
 ////////////////////////////////////////////////////////////////////////
 ///                     FUNCTION DEFINITIONS                         ///
@@ -66,9 +68,9 @@ static int Io_ReadBlifNetworkDefaultInputArrival( Io_ReadBlif_t * p, Vec_Ptr_t *
 
 /**Function*************************************************************
 
-  Synopsis    [Reads the network from a BLIF file.]
+  Synopsis    [Reads the (hierarchical) network from the BLIF file.]
 
-  Description [Works only for flat (non-hierarchical) BLIF.]
+  Description []
                
   SideEffects []
 
@@ -78,34 +80,22 @@ static int Io_ReadBlifNetworkDefaultInputArrival( Io_ReadBlif_t * p, Vec_Ptr_t *
 Abc_Ntk_t * Io_ReadBlif( char * pFileName, int fCheck )
 {
     Io_ReadBlif_t * p;
-    Abc_Ntk_t * pNtk, * pNtkExdc;
+    Abc_Ntk_t * pNtk;
 
     // start the file
     p = Io_ReadBlifFile( pFileName );
     if ( p == NULL )
         return NULL;
 
-    // read the network
+    // read the hierarchical network
     pNtk = Io_ReadBlifNetwork( p );
     if ( pNtk == NULL )
     {
         Io_ReadBlifFree( p );
         return NULL;
     }
+    pNtk->pSpec = Extra_UtilStrsav( pFileName );
     Abc_NtkTimeInitialize( pNtk );
-
-    // read the EXDC network
-    if ( p->fParsingExdc )
-    {
-        pNtkExdc = Io_ReadBlifNetwork( p );
-        if ( pNtkExdc == NULL )
-        {
-            Abc_NtkDelete( pNtk );
-            Io_ReadBlifFree( p );
-            return NULL;
-        }
-        pNtk->pExdc = pNtkExdc;
-    }
     Io_ReadBlifFree( p );
 
     // make sure that everything is okay with the network structure
@@ -120,7 +110,7 @@ Abc_Ntk_t * Io_ReadBlif( char * pFileName, int fCheck )
 
 /**Function*************************************************************
 
-  Synopsis    [Starts the reading data structure.]
+  Synopsis    [Iteratively reads several networks in the hierarchical design.]
 
   Description []
                
@@ -129,141 +119,76 @@ Abc_Ntk_t * Io_ReadBlif( char * pFileName, int fCheck )
   SeeAlso     []
 
 ***********************************************************************/
-Io_ReadBlif_t * Io_ReadBlifFile( char * pFileName )
+Abc_Ntk_t * Io_ReadBlifNetwork( Io_ReadBlif_t * p )
 {
-    Extra_FileReader_t * pReader;
-    Io_ReadBlif_t * p;
-
-    // start the reader
-    pReader = Extra_FileReaderAlloc( pFileName, "#", "\n\r", " \t" );
+    Abc_Ntk_t * pNtk, * pNtkMaster;
 
-    if ( pReader == NULL )
+    // read the name of the master network
+    p->vTokens = Io_ReadBlifGetTokens(p);
+    if ( p->vTokens == NULL || strcmp( p->vTokens->pArray[0], ".model" ) )
+    {
+        p->LineCur = 0;
+        sprintf( p->sError, "Wrong input file format." );
+        Io_ReadBlifPrintErrorMessage( p );
         return NULL;
+    }
 
-    // start the reading data structure
-    p = ALLOC( Io_ReadBlif_t, 1 );
-    memset( p, 0, sizeof(Io_ReadBlif_t) );
-    p->pFileName  = pFileName;
-    p->pReader    = pReader;
-    p->Output     = stdout;
-    p->vNewTokens = Vec_PtrAlloc( 100 );
-    p->vCubes     = Vec_StrAlloc( 100 );
-    return p;
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Frees the data structure.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Io_ReadBlifFree( Io_ReadBlif_t * p )
-{
-    Extra_FileReaderFree( p->pReader );
-    Vec_PtrFree( p->vNewTokens );
-    Vec_StrFree( p->vCubes );
-    free( p );
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Prints the error message including the file name and line number.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-void Io_ReadBlifPrintErrorMessage( Io_ReadBlif_t * p )
-{
-    if ( p->LineCur == 0 ) // the line number is not given
-        fprintf( p->Output, "%s: %s\n", p->pFileName, p->sError );
-    else // print the error message with the line number
-        fprintf( p->Output, "%s (line %d): %s\n", p->pFileName, p->LineCur, p->sError );
-}
-
-/**Function*************************************************************
-
-  Synopsis    [Gets the tokens taking into account the line breaks.]
-
-  Description []
-               
-  SideEffects []
-
-  SeeAlso     []
-
-***********************************************************************/
-Vec_Ptr_t * Io_ReadBlifGetTokens( Io_ReadBlif_t * p )
-{
-    Vec_Ptr_t * vTokens;
-    char * pLastToken;
-    int i;
-
-    // get rid of the old tokens
-    if ( p->vNewTokens->nSize > 0 )
+    // read networks (with EXDC) 
+    pNtkMaster = NULL;
+    while ( p->vTokens )
     {
-        for ( i = 0; i < p->vNewTokens->nSize; i++ )
-            free( p->vNewTokens->pArray[i] );
-        p->vNewTokens->nSize = 0;
+        // read the network and its EXDC if present
+        pNtk = Io_ReadBlifNetworkOne( p );
+        if ( pNtk == NULL )
+            break;
+        if ( p->vTokens && strcmp(p->vTokens->pArray[0], ".exdc") == 0 )
+        {
+            pNtk->pExdc = Io_ReadBlifNetworkOne( p );
+            Abc_NtkFinalizeRead( pNtk->pExdc );
+            if ( pNtk->pExdc == NULL )
+                break;
+        }
+        // add this network as part of the hierarchy
+        if ( pNtkMaster == NULL ) // no master network so far
+        {
+            pNtkMaster = pNtk;
+            continue;
+        }
+        // make sure hierarchy does not have the network with this name
+        if ( pNtkMaster->tName2Model && stmm_is_member( pNtkMaster->tName2Model, pNtk->pName ) )
+        {
+            p->LineCur = 0;
+            sprintf( p->sError, "Model %s is multiply defined in the file.", pNtk->pName );
+            Io_ReadBlifPrintErrorMessage( p );
+            Abc_NtkDelete( pNtk );
+            Abc_NtkDelete( pNtkMaster );
+            pNtkMaster = NULL;
+            return NULL;
+        }
+        // add the network to the hierarchy
+        if ( pNtkMaster->tName2Model == NULL )
+            pNtkMaster->tName2Model = stmm_init_table(strcmp, stmm_strhash);
+        stmm_insert( pNtkMaster->tName2Model, pNtk->pName, (char *)pNtk );
     }
 
-    // get the new tokens
-    vTokens = Extra_FileReaderGetTokens(p->pReader);
-    if ( vTokens == NULL )
-        return vTokens;
-
-    // check if there is a transfer to another line
-    pLastToken = vTokens->pArray[vTokens->nSize - 1];
-    if ( pLastToken[ strlen(pLastToken)-1 ] != '\\' )
-        return vTokens;
-
-    // remove the slash
-    pLastToken[ strlen(pLastToken)-1 ] = 0;
-    if ( pLastToken[0] == 0 )
-        vTokens->nSize--;
-    // load them into the new array
-    for ( i = 0; i < vTokens->nSize; i++ )
-        Vec_PtrPush( p->vNewTokens, Extra_UtilStrsav(vTokens->pArray[i]) );
-
-    // load as long as there is the line break
-    while ( 1 )
+    // if there is a hierarchy, connect the boxes
+    if ( pNtkMaster && pNtkMaster->tName2Model )
     {
-        // get the new tokens
-        vTokens = Extra_FileReaderGetTokens(p->pReader);
-        if ( vTokens->nSize == 0 )
-            return p->vNewTokens;
-        // check if there is a transfer to another line
-        pLastToken = vTokens->pArray[vTokens->nSize - 1];
-        if ( pLastToken[ strlen(pLastToken)-1 ] == '\\' )
+        if ( Io_ReadBlifNetworkConnectBoxes( p, pNtkMaster ) )
         {
-            // remove the slash
-            pLastToken[ strlen(pLastToken)-1 ] = 0;
-            if ( pLastToken[0] == 0 )
-                vTokens->nSize--;
-            // load them into the new array
-            for ( i = 0; i < vTokens->nSize; i++ )
-                Vec_PtrPush( p->vNewTokens, Extra_UtilStrsav(vTokens->pArray[i]) );
-            continue;
+            Abc_NtkDelete( pNtkMaster );
+            return NULL;
         }
-        // otherwise, load them and break
-        for ( i = 0; i < vTokens->nSize; i++ )
-            Vec_PtrPush( p->vNewTokens, Extra_UtilStrsav(vTokens->pArray[i]) );
-        break;
     }
-    return p->vNewTokens;
+    else
+        Abc_NtkFinalizeRead( pNtkMaster );
+    // return the master network
+    return pNtkMaster;
 }
 
-
 /**Function*************************************************************
 
-  Synopsis    [Reads the BLIF file.]
+  Synopsis    [Reads one (main or exdc) network from the BLIF file.]
 
   Description []
                
@@ -272,74 +197,71 @@ Vec_Ptr_t * Io_ReadBlifGetTokens( Io_ReadBlif_t * p )
   SeeAlso     []
 
 ***********************************************************************/
-Abc_Ntk_t * Io_ReadBlifNetwork( Io_ReadBlif_t * p )
+Abc_Ntk_t * Io_ReadBlifNetworkOne( Io_ReadBlif_t * p )
 {
     ProgressBar * pProgress;
-    Vec_Ptr_t * vTokens;
-    char * pModelName, * pDirective;
+    Abc_Ntk_t * pNtk;
+    char * pDirective;
     int iLine, fTokensReady, fStatus;
 
+    // make sure the tokens are present
+    assert( p->vTokens != NULL );
+
+    // create the new network
+    p->pNtkCur = pNtk = Abc_NtkAlloc( ABC_NTK_NETLIST, ABC_FUNC_SOP );
     // read the model name
-    if ( !p->fParsingExdc )
-    {
-        // read the model name
-        vTokens = Io_ReadBlifGetTokens(p);
-        if ( vTokens == NULL || strcmp( vTokens->pArray[0], ".model" ) )
-        {
-            p->LineCur = 0;
-            sprintf( p->sError, "Wrong input file format." );
-            Io_ReadBlifPrintErrorMessage( p );
-            return NULL;
-        }
-        pModelName = vTokens->pArray[1];
-        // allocate the empty network
-        p->pNtk = Abc_NtkAlloc( ABC_NTK_NETLIST, ABC_FUNC_SOP );
-        p->pNtk->pName = Extra_UtilStrsav( pModelName );
-        p->pNtk->pSpec = Extra_UtilStrsav( p->pFileName );
-    }
-    else
-        p->pNtk = Abc_NtkAlloc( ABC_NTK_NETLIST, ABC_FUNC_SOP );
+    if ( strcmp( p->vTokens->pArray[0], ".model" ) == 0 )
+        pNtk->pName = Extra_UtilStrsav( p->vTokens->pArray[1] );
 
     // read the inputs/outputs
     pProgress = Extra_ProgressBarStart( stdout, Extra_FileReaderGetFileSize(p->pReader) );
     fTokensReady = fStatus = 0;
-    for ( iLine = 0; fTokensReady || (vTokens = Io_ReadBlifGetTokens(p)); iLine++ )
+    for ( iLine = 0; fTokensReady || (p->vTokens = Io_ReadBlifGetTokens(p)); iLine++ )
     {
         if ( iLine % 1000 == 0 )
         Extra_ProgressBarUpdate( pProgress, Extra_FileReaderGetCurPosition(p->pReader), NULL );
 
         // consider different line types
         fTokensReady = 0;
-        pDirective = vTokens->pArray[0];
+        pDirective = p->vTokens->pArray[0];
         if ( !strcmp( pDirective, ".names" ) )
-            { fStatus = Io_ReadBlifNetworkNames( p, &vTokens ); fTokensReady = 1; }
+            { fStatus = Io_ReadBlifNetworkNames( p, &p->vTokens ); fTokensReady = 1; }
         else if ( !strcmp( pDirective, ".gate" ) )
-            fStatus = Io_ReadBlifNetworkGate( p, vTokens );
+            fStatus = Io_ReadBlifNetworkGate( p, p->vTokens );
         else if ( !strcmp( pDirective, ".latch" ) )
-            fStatus = Io_ReadBlifNetworkLatch( p, vTokens );
+            fStatus = Io_ReadBlifNetworkLatch( p, p->vTokens );
         else if ( !strcmp( pDirective, ".inputs" ) )
-            fStatus = Io_ReadBlifNetworkInputs( p, vTokens );
+            fStatus = Io_ReadBlifNetworkInputs( p, p->vTokens );
         else if ( !strcmp( pDirective, ".outputs" ) )
-            fStatus = Io_ReadBlifNetworkOutputs( p, vTokens );
+            fStatus = Io_ReadBlifNetworkOutputs( p, p->vTokens );
         else if ( !strcmp( pDirective, ".input_arrival" ) )
-            fStatus = Io_ReadBlifNetworkInputArrival( p, vTokens );
+            fStatus = Io_ReadBlifNetworkInputArrival( p, p->vTokens );
         else if ( !strcmp( pDirective, ".default_input_arrival" ) )
-            fStatus = Io_ReadBlifNetworkDefaultInputArrival( p, vTokens );
+            fStatus = Io_ReadBlifNetworkDefaultInputArrival( p, p->vTokens );
+        else if ( !strcmp( pDirective, ".subckt" ) )
+            fStatus = Io_ReadBlifNetworkSubcircuit( p, p->vTokens );
         else if ( !strcmp( pDirective, ".exdc" ) )
-            { p->fParsingExdc = 1; break; }
+            break;
         else if ( !strcmp( pDirective, ".end" ) )
+        {
+            p->vTokens = Io_ReadBlifGetTokens(p);
             break;
+        }
+        else if ( !strcmp( pDirective, ".blackbox" ) )
+        {
+            pNtk->ntkType = ABC_NTK_BLACKBOX;
+            pNtk->ntkFunc = ABC_FUNC_BLACKBOX;
+        }
         else
             printf( "%s (line %d): Skipping directive \"%s\".\n", p->pFileName, 
                 Extra_FileReaderGetLineNumber(p->pReader, 0), pDirective );
-        if ( vTokens == NULL ) // some files do not have ".end" in the end
+        if ( p->vTokens == NULL ) // some files do not have ".end" in the end
             break;
         if ( fStatus == 1 )
             return NULL;
     }
     Extra_ProgressBarStop( pProgress );
-    Abc_NtkFinalizeRead( p->pNtk );
-    return p->pNtk;
+    return pNtk;
 }
 
 /**Function*************************************************************
@@ -357,7 +279,7 @@ int Io_ReadBlifNetworkInputs( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
 {
     int i;
     for ( i = 1; i < vTokens->nSize; i++ )
-        Io_ReadCreatePi( p->pNtk, vTokens->pArray[i] );
+        Io_ReadCreatePi( p->pNtkCur, vTokens->pArray[i] );
     return 0;
 }
 
@@ -376,7 +298,7 @@ int Io_ReadBlifNetworkOutputs( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
 {
     int i;
     for ( i = 1; i < vTokens->nSize; i++ )
-        Io_ReadCreatePo( p->pNtk, vTokens->pArray[i] );
+        Io_ReadCreatePo( p->pNtkCur, vTokens->pArray[i] );
     return 0;
 }
 
@@ -393,7 +315,7 @@ int Io_ReadBlifNetworkOutputs( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
 ***********************************************************************/
 int Io_ReadBlifNetworkLatch( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
 {
-    Abc_Ntk_t * pNtk = p->pNtk;
+    Abc_Ntk_t * pNtk = p->pNtkCur;
     Abc_Obj_t * pLatch;
     int ResetValue;
     if ( vTokens->nSize < 3 )
@@ -442,7 +364,7 @@ int Io_ReadBlifNetworkLatch( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
 int Io_ReadBlifNetworkNames( Io_ReadBlif_t * p, Vec_Ptr_t ** pvTokens )
 {
     Vec_Ptr_t * vTokens = *pvTokens;
-    Abc_Ntk_t * pNtk = p->pNtk;
+    Abc_Ntk_t * pNtk = p->pNtkCur;
     Abc_Obj_t * pNode;
     char * pToken, Char, ** ppNames;
     int nFanins, nNames;
@@ -584,12 +506,12 @@ int Io_ReadBlifNetworkGate( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
     }
 
     // if this is the first line with gate, update the network type
-    if ( Abc_NtkNodeNum(p->pNtk) == 0 )
+    if ( Abc_NtkNodeNum(p->pNtkCur) == 0 )
     {
-        assert( p->pNtk->ntkFunc == ABC_FUNC_SOP );
-        p->pNtk->ntkFunc = ABC_FUNC_MAP;
-        Extra_MmFlexStop( p->pNtk->pManFunc, 0 );
-        p->pNtk->pManFunc = pGenlib;
+        assert( p->pNtkCur->ntkFunc == ABC_FUNC_SOP );
+        p->pNtkCur->ntkFunc = ABC_FUNC_MAP;
+        Extra_MmFlexStop( p->pNtkCur->pManFunc, 0 );
+        p->pNtkCur->pManFunc = pGenlib;
     }
 
     // remove the formal parameter names
@@ -608,13 +530,53 @@ int Io_ReadBlifNetworkGate( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
     // create the node
     ppNames = (char **)vTokens->pArray + 2;
     nNames  = vTokens->nSize - 3;
-    pNode   = Io_ReadCreateNode( p->pNtk, ppNames[nNames], ppNames, nNames );
+    pNode   = Io_ReadCreateNode( p->pNtkCur, ppNames[nNames], ppNames, nNames );
 
     // set the pointer to the functionality of the node
     Abc_ObjSetData( pNode, pGate );
     return 0;
 }
 
+/**Function*************************************************************
+
+  Synopsis    [Creates a multi-input multi-output box in the hierarchical design.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Io_ReadBlifNetworkSubcircuit( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
+{
+    Abc_Obj_t * pBox;
+    Vec_Ptr_t * vNames;
+    char * pName;
+    int i;
+
+    // create a new node and add it to the network
+    if ( vTokens->nSize < 3 )
+    {
+        p->LineCur = Extra_FileReaderGetLineNumber(p->pReader, 0);
+        sprintf( p->sError, "The .subcircuit line has less than three tokens." );
+        Io_ReadBlifPrintErrorMessage( p );
+        return 1;
+    }
+
+    // store the names of formal/actual inputs/outputs of the box
+    vNames = Vec_PtrAlloc( 10 );
+    Vec_PtrForEachEntryStart( vTokens, pName, i, 1 )
+        Vec_PtrPush( vNames, Abc_NtkRegisterName(p->pNtkCur, pName) );
+
+    // create a new box and add it to the network
+    pBox = Abc_NtkCreateBox( p->pNtkCur );
+    // set the pointer to the node names
+    Abc_ObjSetData( pBox, vNames );
+    // remember the line of the file
+    pBox->pCopy = (void *)Extra_FileReaderGetLineNumber(p->pReader, 0);
+    return 0;
+}
 
 /**Function*************************************************************
 
@@ -663,7 +625,7 @@ int Io_ReadBlifNetworkInputArrival( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
         Io_ReadBlifPrintErrorMessage( p );
         return 1;
     }
-    pNet = Abc_NtkFindNet( p->pNtk, vTokens->pArray[1] );
+    pNet = Abc_NtkFindNet( p->pNtkCur, vTokens->pArray[1] );
     if ( pNet == NULL )
     {
         p->LineCur = Extra_FileReaderGetLineNumber(p->pReader, 0);
@@ -681,7 +643,7 @@ int Io_ReadBlifNetworkInputArrival( Io_ReadBlif_t * p, Vec_Ptr_t * vTokens )
         return 1;
     }
     // set the arrival time
-    Abc_NtkTimeSetArrival( p->pNtk, Abc_ObjFanin0(pNet)->Id, (float)TimeRise, (float)TimeFall );
+    Abc_NtkTimeSetArrival( p->pNtkCur, Abc_ObjFanin0(pNet)->Id, (float)TimeRise, (float)TimeFall );
     return 0;
 }
 
@@ -720,10 +682,354 @@ int Io_ReadBlifNetworkDefaultInputArrival( Io_ReadBlif_t * p, Vec_Ptr_t * vToken
         return 1;
     }
     // set the arrival time
-    Abc_NtkTimeSetDefaultArrival( p->pNtk, (float)TimeRise, (float)TimeFall );
+    Abc_NtkTimeSetDefaultArrival( p->pNtkCur, (float)TimeRise, (float)TimeFall );
+    return 0;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Prints the error message including the file name and line number.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Io_ReadBlifPrintErrorMessage( Io_ReadBlif_t * p )
+{
+    if ( p->LineCur == 0 ) // the line number is not given
+        fprintf( p->Output, "%s: %s\n", p->pFileName, p->sError );
+    else // print the error message with the line number
+        fprintf( p->Output, "%s (line %d): %s\n", p->pFileName, p->LineCur, p->sError );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Gets the tokens taking into account the line breaks.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Ptr_t * Io_ReadBlifGetTokens( Io_ReadBlif_t * p )
+{
+    Vec_Ptr_t * vTokens;
+    char * pLastToken;
+    int i;
+
+    // get rid of the old tokens
+    if ( p->vNewTokens->nSize > 0 )
+    {
+        for ( i = 0; i < p->vNewTokens->nSize; i++ )
+            free( p->vNewTokens->pArray[i] );
+        p->vNewTokens->nSize = 0;
+    }
+
+    // get the new tokens
+    vTokens = Extra_FileReaderGetTokens(p->pReader);
+    if ( vTokens == NULL )
+        return vTokens;
+
+    // check if there is a transfer to another line
+    pLastToken = vTokens->pArray[vTokens->nSize - 1];
+    if ( pLastToken[ strlen(pLastToken)-1 ] != '\\' )
+        return vTokens;
+
+    // remove the slash
+    pLastToken[ strlen(pLastToken)-1 ] = 0;
+    if ( pLastToken[0] == 0 )
+        vTokens->nSize--;
+    // load them into the new array
+    for ( i = 0; i < vTokens->nSize; i++ )
+        Vec_PtrPush( p->vNewTokens, Extra_UtilStrsav(vTokens->pArray[i]) );
+
+    // load as long as there is the line break
+    while ( 1 )
+    {
+        // get the new tokens
+        vTokens = Extra_FileReaderGetTokens(p->pReader);
+        if ( vTokens->nSize == 0 )
+            return p->vNewTokens;
+        // check if there is a transfer to another line
+        pLastToken = vTokens->pArray[vTokens->nSize - 1];
+        if ( pLastToken[ strlen(pLastToken)-1 ] == '\\' )
+        {
+            // remove the slash
+            pLastToken[ strlen(pLastToken)-1 ] = 0;
+            if ( pLastToken[0] == 0 )
+                vTokens->nSize--;
+            // load them into the new array
+            for ( i = 0; i < vTokens->nSize; i++ )
+                Vec_PtrPush( p->vNewTokens, Extra_UtilStrsav(vTokens->pArray[i]) );
+            continue;
+        }
+        // otherwise, load them and break
+        for ( i = 0; i < vTokens->nSize; i++ )
+            Vec_PtrPush( p->vNewTokens, Extra_UtilStrsav(vTokens->pArray[i]) );
+        break;
+    }
+    return p->vNewTokens;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Starts the reading data structure.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Io_ReadBlif_t * Io_ReadBlifFile( char * pFileName )
+{
+    Extra_FileReader_t * pReader;
+    Io_ReadBlif_t * p;
+
+    // start the reader
+    pReader = Extra_FileReaderAlloc( pFileName, "#", "\n\r", " \t" );
+
+    if ( pReader == NULL )
+        return NULL;
+
+    // start the reading data structure
+    p = ALLOC( Io_ReadBlif_t, 1 );
+    memset( p, 0, sizeof(Io_ReadBlif_t) );
+    p->pFileName  = pFileName;
+    p->pReader    = pReader;
+    p->Output     = stdout;
+    p->vNewTokens = Vec_PtrAlloc( 100 );
+    p->vCubes     = Vec_StrAlloc( 100 );
+    return p;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Frees the data structure.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Io_ReadBlifFree( Io_ReadBlif_t * p )
+{
+    Extra_FileReaderFree( p->pReader );
+    Vec_PtrFree( p->vNewTokens );
+    Vec_StrFree( p->vCubes );
+    free( p );
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Connect one box.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Io_ReadBlifNetworkConnectBoxesOneBox( Io_ReadBlif_t * p, Abc_Obj_t * pBox, stmm_table * tName2Model )
+{
+    Vec_Ptr_t * pNames;
+    Abc_Ntk_t * pNtkModel;
+    Abc_Obj_t * pObj, * pNet;
+    char * pName, * pActual;
+    int i, Length, Start;
+
+    // get the model for this box
+    pNames = pBox->pData;
+    if ( !stmm_lookup( tName2Model, Vec_PtrEntry(pNames, 0), (char **)&pNtkModel ) )
+    {
+        p->LineCur = (int)pBox->pCopy;
+        sprintf( p->sError, "Cannot find the model for subcircuit %s.", Vec_PtrEntry(pNames, 0) );
+        Io_ReadBlifPrintErrorMessage( p );
+        return 1;
+    }
+
+    // create the fanins of the box
+    Abc_NtkForEachPi( pNtkModel, pObj, i )
+        pObj->pCopy = NULL;
+    Vec_PtrForEachEntryStart( pNames, pName, i, 1 )
+    {
+        pActual = Io_ReadBlifCleanName(pName);
+        if ( pActual == NULL )
+        {
+            p->LineCur = (int)pBox->pCopy;
+            sprintf( p->sError, "Cannot parse formal/actual name pair \"%s\".", pName );
+            Io_ReadBlifPrintErrorMessage( p );
+            return 1;
+        }
+        Length = pActual - pName - 1;
+        pName[Length] = 0;
+        // find the PI net with this name
+        pObj = Abc_NtkFindNet( pNtkModel, pName );
+        if ( pObj == NULL )
+        {
+            p->LineCur = (int)pBox->pCopy;
+            sprintf( p->sError, "Cannot find formal input \"%s\" as an PI of model \"%s\".", pName, Vec_PtrEntry(pNames, 0) );
+            Io_ReadBlifPrintErrorMessage( p );
+            return 1;
+        }
+        // get the PI
+        pObj = Abc_ObjFanin0(pObj);
+        // quit if this is not a PI net
+        if ( !Abc_ObjIsPi(pObj) )
+        {
+            pName[Length] = '=';
+            Start = i;
+            break;
+        }
+        // remember the actual name in the net
+        if ( pObj->pCopy != NULL )
+        {
+            p->LineCur = (int)pBox->pCopy;
+            sprintf( p->sError, "Formal input \"%s\" is used more than once.", pName );
+            Io_ReadBlifPrintErrorMessage( p );
+            return 1;
+        }
+        pObj->pCopy = (void *)pActual;
+        // quit if we processed all PIs
+        if ( i == Abc_NtkPiNum(pNtkModel) )
+        {
+            Start = i+1;
+            break;
+        }
+    }
+    // create the fanins of the box
+    Abc_NtkForEachPi( pNtkModel, pObj, i )
+    {
+        pActual = (void *)pObj->pCopy;
+        if ( pActual == NULL )
+        {
+            p->LineCur = (int)pBox->pCopy;
+            sprintf( p->sError, "Formal input \"%s\" of model %s is not driven.", pName, Vec_PtrEntry(pNames, 0) );
+            Io_ReadBlifPrintErrorMessage( p );
+            return 1;
+        }
+        pNet = Abc_NtkFindOrCreateNet( pBox->pNtk, pActual );
+        Abc_ObjAddFanin( pBox, pNet );
+    }
+    Abc_NtkForEachPi( pNtkModel, pObj, i )
+        pObj->pCopy = NULL;
+
+    // create the fanouts of the box
+    Abc_NtkForEachPo( pNtkModel, pObj, i )
+        pObj->pCopy = NULL;
+    Vec_PtrForEachEntryStart( pNames, pName, i, Start )
+    {
+        pActual = Io_ReadBlifCleanName(pName);
+        if ( pActual == NULL )
+        {
+            p->LineCur = (int)pBox->pCopy;
+            sprintf( p->sError, "Cannot parse formal/actual name pair \"%s\".", pName );
+            Io_ReadBlifPrintErrorMessage( p );
+            return 1;
+        }
+        Length = pActual - pName - 1;
+        pName[Length] = 0;
+        // find the PO net with this name
+        pObj = Abc_NtkFindNet( pNtkModel, pName );
+        if ( pObj == NULL )
+        {
+            p->LineCur = (int)pBox->pCopy;
+            sprintf( p->sError, "Cannot find formal output \"%s\" as an PO of model \"%s\".", pName, Vec_PtrEntry(pNames, 0) );
+            Io_ReadBlifPrintErrorMessage( p );
+            return 1;
+        }
+        // get the PO
+        pObj = Abc_ObjFanout0(pObj);
+        if ( pObj->pCopy != NULL )
+        {
+            p->LineCur = (int)pBox->pCopy;
+            sprintf( p->sError, "Formal output \"%s\" is used more than once.", pName );
+            Io_ReadBlifPrintErrorMessage( p );
+            return 1;
+        }
+        pObj->pCopy = (void *)pActual;
+    }
+    // create the fanouts of the box
+    Abc_NtkForEachPo( pNtkModel, pObj, i )
+    {
+        pActual = (void *)pObj->pCopy;
+        if ( pActual == NULL )
+        {
+            p->LineCur = (int)pBox->pCopy;
+            sprintf( p->sError, "Formal output \"%s\" of model %s is not driven.", pName, Vec_PtrEntry(pNames, 0) );
+            Io_ReadBlifPrintErrorMessage( p );
+            return 1;
+        }
+        pNet = Abc_NtkFindOrCreateNet( pBox->pNtk, pActual );
+        Abc_ObjAddFanin( pNet, pBox );
+    }
+    Abc_NtkForEachPo( pNtkModel, pObj, i )
+        pObj->pCopy = NULL;
+
+    // remove the array of names, assign the pointer to the model
+    Vec_PtrFree( pBox->pData );
+    pBox->pData = pNtkModel;
     return 0;
 }
 
+/**Function*************************************************************
+
+  Synopsis    [Connect the boxes in the hierarchy of networks.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Io_ReadBlifNetworkConnectBoxesOne( Io_ReadBlif_t * p, Abc_Ntk_t * pNtk, stmm_table * tName2Model )
+{
+    Abc_Obj_t * pBox;
+    int i;
+    // go through the boxes
+    Abc_NtkForEachBox( pNtk, pBox, i )
+        if ( Io_ReadBlifNetworkConnectBoxesOneBox( p, pBox, tName2Model ) )
+            return 1;
+    Abc_NtkFinalizeRead( pNtk );
+    return 0;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Connect the boxes in the hierarchy of networks.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Io_ReadBlifNetworkConnectBoxes( Io_ReadBlif_t * p, Abc_Ntk_t * pNtkMaster )
+{
+    stmm_generator * gen;
+    Abc_Ntk_t * pNtk;
+    char * pName;
+    // connect the master network
+    if ( Io_ReadBlifNetworkConnectBoxesOne( p, pNtkMaster, pNtkMaster->tName2Model ) )
+        return 1;
+    // connect other networks
+    stmm_foreach_item( pNtkMaster->tName2Model, gen, &pName, (char **)&pNtk )
+        if ( Io_ReadBlifNetworkConnectBoxesOne( p, pNtk, pNtkMaster->tName2Model ) )
+            return 1;
+    return 0;
+}
 
 ////////////////////////////////////////////////////////////////////////
 ///                       END OF FILE                                ///
diff --git a/src/base/io/ioWriteBlif.c b/src/base/io/ioWriteBlif.c
index 1b515a1e..1e27498d 100644
--- a/src/base/io/ioWriteBlif.c
+++ b/src/base/io/ioWriteBlif.c
@@ -26,6 +26,7 @@
 ///                        DECLARATIONS                              ///
 ////////////////////////////////////////////////////////////////////////
 
+static void Io_NtkWrite( FILE * pFile, Abc_Ntk_t * pNtk, int fWriteLatches );
 static void Io_NtkWriteOne( FILE * pFile, Abc_Ntk_t * pNtk, int fWriteLatches );
 static void Io_NtkWritePis( FILE * pFile, Abc_Ntk_t * pNtk, int fWriteLatches );
 static void Io_NtkWritePos( FILE * pFile, Abc_Ntk_t * pNtk, int fWriteLatches );
@@ -59,7 +60,7 @@ void Io_WriteBlifLogic( Abc_Ntk_t * pNtk, char * FileName, int fWriteLatches )
         fprintf( stdout, "Writing BLIF has failed.\n" );
         return;
     }
-    Io_WriteBlif( pNtkTemp, FileName, fWriteLatches );
+    Io_WriteBlifNetlist( pNtkTemp, FileName, fWriteLatches );
     Abc_NtkDelete( pNtkTemp );
 }
 
@@ -74,19 +75,48 @@ void Io_WriteBlifLogic( Abc_Ntk_t * pNtk, char * FileName, int fWriteLatches )
   SeeAlso     []
 
 ***********************************************************************/
-void Io_WriteBlif( Abc_Ntk_t * pNtk, char * FileName, int fWriteLatches )
+void Io_WriteBlifNetlist( Abc_Ntk_t * pNtk, char * FileName, int fWriteLatches )
 {
-    Abc_Ntk_t * pExdc;
+    stmm_generator * gen;
+    Abc_Ntk_t * pNtkTemp;
     FILE * pFile;
     assert( Abc_NtkIsNetlist(pNtk) );
+    // start writing the file
     pFile = fopen( FileName, "w" );
     if ( pFile == NULL )
     {
-        fprintf( stdout, "Io_WriteBlif(): Cannot open the output file.\n" );
+        fprintf( stdout, "Io_WriteBlifNetlist(): Cannot open the output file.\n" );
         return;
     }
-    // write the model name
     fprintf( pFile, "# Benchmark \"%s\" written by ABC on %s\n", pNtk->pName, Extra_TimeStamp() );
+    // write the master network
+    Io_NtkWrite( pFile, pNtk, fWriteLatches );
+    // write the hierarchy if present
+    if ( pNtk->tName2Model )
+    {
+        fprintf( pFile, "\n\n" );
+        stmm_foreach_item( pNtk->tName2Model, gen, NULL, (char **)&pNtkTemp )
+            Io_NtkWrite( pFile, pNtkTemp, fWriteLatches );
+    }
+    fclose( pFile );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Write the network into a BLIF file with the given name.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Io_NtkWrite( FILE * pFile, Abc_Ntk_t * pNtk, int fWriteLatches )
+{
+    Abc_Ntk_t * pExdc;
+    assert( Abc_NtkIsNetlist(pNtk) || Abc_NtkIsBlackbox(pNtk) );
+    // write the model name
     fprintf( pFile, ".model %s\n", Abc_NtkName(pNtk) );
     // write the network
     Io_NtkWriteOne( pFile, pNtk, fWriteLatches );
@@ -100,7 +130,6 @@ void Io_WriteBlif( Abc_Ntk_t * pNtk, char * FileName, int fWriteLatches )
     }
     // finalize the file
     fprintf( pFile, ".end\n" );
-    fclose( pFile );
 }
 
 /**Function*************************************************************
@@ -130,6 +159,13 @@ void Io_NtkWriteOne( FILE * pFile, Abc_Ntk_t * pNtk, int fWriteLatches )
     Io_NtkWritePos( pFile, pNtk, fWriteLatches );
     fprintf( pFile, "\n" );
 
+    // write the blackbox
+    if ( Abc_NtkIsBlackbox( pNtk ) )
+    {
+        fprintf( pFile, ".blackbox\n" );
+        return;
+    }
+
     // write the timing info
     Io_WriteTimingInfo( pFile, pNtk );