merge

16 files changed, 728 insertions, 55 deletions

diff --git a/src/base/abc/abcUtil.c b/src/base/abc/abcUtil.c
index dc6cd3b3..6b67d82a 100644
--- a/src/base/abc/abcUtil.c
+++ b/src/base/abc/abcUtil.c
@@ -3109,7 +3109,9 @@ int Abc_GateToType( Abc_Obj_t * pObj )
     if ( !strncmp(pGateName, "or",   2) )  return ABC_OPER_BIT_OR;
     if ( !strncmp(pGateName, "nor",  3) )  return ABC_OPER_BIT_NOR;
     if ( !strncmp(pGateName, "xor",  3) )  return ABC_OPER_BIT_XOR;
-    if ( !strncmp(pGateName, "nxor", 4) )  return ABC_OPER_BIT_NXOR;
+    if ( !strncmp(pGateName, "xnor", 4) )  return ABC_OPER_BIT_NXOR;
+    if ( !strncmp(pGateName, "zero", 4) )  return ABC_OPER_CONST_F;
+    if ( !strncmp(pGateName, "one",  3) )  return ABC_OPER_CONST_T;
     assert( 0 );
     return -1;
 }
@@ -3141,6 +3143,81 @@ Vec_Wec_t * Abc_SopSynthesize( Vec_Ptr_t * vSops )
     return vRes;
 }
 
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Abc_NtkClpOneGia_rec( Gia_Man_t * pNew, Abc_Obj_t * pNode )
+{
+    int iLit0, iLit1;
+    if ( Abc_NodeIsTravIdCurrent(pNode) || Abc_ObjFaninNum(pNode) == 0 || Abc_ObjIsCi(pNode) )
+        return pNode->iTemp;
+    assert( Abc_ObjIsNode( pNode ) );
+    Abc_NodeSetTravIdCurrent( pNode );
+    iLit0 = Abc_NtkClpOneGia_rec( pNew, Abc_ObjFanin0(pNode) );
+    iLit1 = Abc_NtkClpOneGia_rec( pNew, Abc_ObjFanin1(pNode) );
+    iLit0 = Abc_LitNotCond( iLit0, Abc_ObjFaninC0(pNode) );
+    iLit1 = Abc_LitNotCond( iLit1, Abc_ObjFaninC1(pNode) );
+    return (pNode->iTemp = Gia_ManHashAnd(pNew, iLit0, iLit1));
+}
+Gia_Man_t * Abc_NtkStrashToGia( Abc_Ntk_t * pNtk )
+{
+    int i, iLit;
+    Abc_Obj_t * pNode;
+    Gia_Man_t * pNew, * pTemp;
+    assert( Abc_NtkIsStrash(pNtk) );
+    Abc_NtkForEachObj( pNtk, pNode, i )
+        pNode->iTemp = -1;
+    // start new manager
+    pNew = Gia_ManStart( Abc_NtkObjNum(pNtk) );
+    pNew->pName = Abc_UtilStrsav( pNtk->pName );
+    pNew->pSpec = Abc_UtilStrsav( pNtk->pSpec );
+    Gia_ManHashStart( pNew );
+    // primary inputs
+    Abc_AigConst1(pNtk)->iTemp = 1;
+    Abc_NtkForEachCi( pNtk, pNode, i )
+        pNode->iTemp = Gia_ManAppendCi(pNew);
+    // create the first cone
+    Abc_NtkIncrementTravId( pNtk );
+    Abc_NtkForEachCo( pNtk, pNode, i )
+    {
+        iLit = Abc_NtkClpOneGia_rec( pNew, Abc_ObjFanin0(pNode) );
+        iLit = Abc_LitNotCond( iLit, Abc_ObjFaninC0(pNode) );
+        Gia_ManAppendCo( pNew, iLit );
+    }
+    // perform cleanup
+    pNew = Gia_ManCleanup( pTemp = pNew );
+    Gia_ManStop( pTemp );
+    return pNew;
+}
+Gia_Man_t * Abc_SopSynthesizeOne( Vec_Ptr_t * vSops )
+{
+    Abc_Ntk_t * pNtkNew, * pNtk;
+    char * pSop = (char *)Vec_PtrEntry(vSops, 0);
+    assert( Vec_PtrSize(vSops) == 1 );
+    if ( strlen(pSop) == 3 )
+    {
+        Gia_Man_t * pNew = Gia_ManStart( 1 );
+        pNew->pName = Abc_UtilStrsav( "top" );
+        //Gia_ManAppendCi( pNew );
+        assert( pSop[1] == '0' || pSop[1] == '1' );
+        Gia_ManAppendCo( pNew, pSop[1] == '1' );
+        return pNew;
+    }
+    pNtk = Abc_NtkCreateFromSops( "top", vSops );
+    Abc_FrameReplaceCurrentNetwork( Abc_FrameReadGlobalFrame(), pNtk );
+    Cmd_CommandExecute( Abc_FrameGetGlobalFrame(), "fx; strash; dc2" );
+    pNtkNew = Abc_FrameReadNtk( Abc_FrameReadGlobalFrame() );
+    return Abc_NtkStrashToGia( pNtkNew );
+}
+
 ////////////////////////////////////////////////////////////////////////
 ///                       END OF FILE                                ///
 ////////////////////////////////////////////////////////////////////////
diff --git a/src/base/abci/abc.c b/src/base/abci/abc.c
index f9f2f2e0..7055bf59 100644
--- a/src/base/abci/abc.c
+++ b/src/base/abci/abc.c
@@ -124,6 +124,7 @@ static int Abc_CommandMfs                    ( Abc_Frame_t * pAbc, int argc, cha
 static int Abc_CommandMfs2                   ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandMfs3                   ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandMfse                   ( Abc_Frame_t * pAbc, int argc, char ** argv );
+static int Abc_CommandLogicPush              ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandTrace                  ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandGlitch                 ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandSpeedup                ( Abc_Frame_t * pAbc, int argc, char ** argv );
@@ -781,6 +782,7 @@ void Abc_Init( Abc_Frame_t * pAbc )
     Cmd_CommandAdd( pAbc, "Synthesis",    "mfs2",          Abc_CommandMfs2,             1 );
     Cmd_CommandAdd( pAbc, "Synthesis",    "mfs3",          Abc_CommandMfs3,             1 );
     Cmd_CommandAdd( pAbc, "Synthesis",    "mfse",          Abc_CommandMfse,              1 );
+    Cmd_CommandAdd( pAbc, "Synthesis",    "logicpush",     Abc_CommandLogicPush,        1 );
     Cmd_CommandAdd( pAbc, "Synthesis",    "trace",         Abc_CommandTrace,            0 );
     Cmd_CommandAdd( pAbc, "Synthesis",    "glitch",        Abc_CommandGlitch,           0 );
     Cmd_CommandAdd( pAbc, "Synthesis",    "speedup",       Abc_CommandSpeedup,          1 );
@@ -4151,7 +4153,7 @@ int Abc_CommandFastExtract( Abc_Frame_t * pAbc, int argc, char ** argv )
         Abc_Print( -1, "Empty network.\n" );
         return 1;
     }
-    if ( Abc_NtkNodeNum(pNtk) == 0 )
+    if ( Abc_NtkNodeNum(pNtk) == 0 || Abc_NtkPiNum(pNtk) == 0 )
     {
         Abc_Print( -1, "The network does not have internal nodes.\n" );
         return 1;
@@ -5807,6 +5809,74 @@ usage:
     return 1;
 }
 
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Abc_CommandLogicPush( Abc_Frame_t * pAbc, int argc, char ** argv )
+{
+    extern Abc_Ntk_t * Abc_NtkOptPush( Abc_Ntk_t * pNtk, int nLutSize, int fVerbose );
+    Abc_Ntk_t * pNtk = Abc_FrameReadNtk(pAbc);
+    Abc_Ntk_t * pNtkRes;
+    int nLutSize = 4;
+    int fVerbose = 0;
+    int c;
+    Extra_UtilGetoptReset();
+    while ( ( c = Extra_UtilGetopt( argc, argv, "Kvh" ) ) != EOF )
+    {
+        switch ( c )
+        {
+        case 'K':
+            if ( globalUtilOptind >= argc )
+            {
+                Abc_Print( -1, "Command line switch \"-K\" should be followed by a positive integer.\n" );
+                goto usage;
+            }
+            nLutSize = atoi(argv[globalUtilOptind]);
+            globalUtilOptind++;
+            if ( nLutSize < 0 )
+                goto usage;
+            break;
+        case 'v':
+            fVerbose ^= 1;
+            break;
+        case 'h':
+            goto usage;
+        default:
+            goto usage;
+        }
+    }
+    if ( pNtk == NULL )
+    {
+        Abc_Print( -1, "Empty network.\n" );
+        return 1;
+    }
+    if ( !Abc_NtkIsLogic(pNtk) )
+    {
+        Abc_Print( -1, "This command can only be applied to a logic network.\n" );
+        return 1;
+    }
+    nLutSize = Abc_MaxInt( nLutSize, Abc_NtkGetFaninMax(pNtk) );
+    Abc_NtkToSop( pNtk, -1, ABC_INFINITY );
+    pNtkRes = Abc_NtkOptPush( pNtk, nLutSize, fVerbose );
+    Abc_FrameReplaceCurrentNetwork( pAbc, pNtkRes );
+    return 0;
+usage:
+    Abc_Print( -2, "usage: logicpush [-K num] [-vh]\n" );
+    Abc_Print( -2, "\t           performs logic pushing to reduce structural bias\n" );
+    Abc_Print( -2, "\t-K <num> : the LUT size used in the mapping [default = %d]\n", nLutSize );
+    Abc_Print( -2, "\t-v       : toggle printing optimization summary [default = %s]\n", fVerbose? "yes": "no" );
+    Abc_Print( -2, "\t-h       : print the command usage\n");
+    return 1;
+}
+
 
 /**Function*************************************************************
 
@@ -18315,7 +18385,7 @@ int Abc_CommandDsdFilter( Abc_Frame_t * pAbc, int argc, char ** argv )
     if ( fInvMarks )
         If_DsdManInvertMarks( pDsd, fVerbose );
 #ifdef ABC_USE_CUDD
-    else
+    else if ( nLimit == 0 )
         Id_DsdManTuneThresh( pDsd, fUnate, fThresh, fThreshHeuristic, fVerbose );
 #endif
     return 0;
diff --git a/src/base/acb/acb.h b/src/base/acb/acb.h
index 7c228acb..baecd161 100644
--- a/src/base/acb/acb.h
+++ b/src/base/acb/acb.h
@@ -256,7 +256,8 @@ static inline int *          Acb_ObjFanins( Acb_Ntk_t * p, int i )
 static inline int            Acb_ObjFanin( Acb_Ntk_t * p, int i, int k )             { return Acb_ObjFanins(p, i)[k+1];                                                                     }
 static inline int            Acb_ObjFaninNum( Acb_Ntk_t * p, int i )                 { return Acb_ObjFanins(p, i)[0];                                                                       }
 static inline int            Acb_ObjFanoutNum( Acb_Ntk_t * p, int i )                { return Vec_IntSize( Vec_WecEntry(&p->vFanouts, i) );                                                 }
-static inline Vec_Int_t *    Acb_ObjFanoutVec( Acb_Ntk_t * p, int i )                { return Vec_WecEntry( &p->vFanouts, i );                                                              }
+static inline Vec_Int_t *    Acb_ObjFanoutVec( Acb_Ntk_t * p, int i )                { assert(i>0); return Vec_WecEntry( &p->vFanouts, i );                                                 }
+static inline int            Acb_ObjFanout( Acb_Ntk_t * p, int i, int k )            { return Vec_IntEntry( Acb_ObjFanoutVec(p, i), k );                                                    }
 static inline int            Acb_ObjFanin0( Acb_Ntk_t * p, int i )                   { return Acb_ObjFanins(p, i)[1];                                                                       }
 static inline int            Acb_ObjCioId( Acb_Ntk_t * p, int i )                    { return Acb_ObjFanins(p, i)[2];                                                                       }
  
@@ -276,7 +277,6 @@ static inline int            Acb_ObjLevelR( Acb_Ntk_t * p, int i )
 static inline int            Acb_ObjPathD( Acb_Ntk_t * p, int i )                    { assert(i>0); return Vec_IntEntry(&p->vPathD, i);                                                     }
 static inline int            Acb_ObjPathR( Acb_Ntk_t * p, int i )                    { assert(i>0); return Vec_IntEntry(&p->vPathR, i);                                                     }
 static inline float          Acb_ObjCounts( Acb_Ntk_t * p, int i )                   { assert(i>0); return Vec_FltEntry(&p->vCounts, i);                                                    }
-static inline Vec_Int_t *    Acb_ObjFanout( Acb_Ntk_t * p, int i )                   { assert(i>0); return Vec_WecEntry(&p->vFanouts, i);                                                   }
 static inline Vec_Str_t *    Acb_ObjCnfs( Acb_Ntk_t * p, int i )                     { assert(i>0); return (Vec_Str_t *)Vec_WecEntry(&p->vCnfs, i);                                         }
 
 static inline void           Acb_ObjSetCopy( Acb_Ntk_t * p, int i, int x )           { assert(Acb_ObjCopy(p, i) == -1); Vec_IntWriteEntry( &p->vObjCopy, i, x );                            }
@@ -361,6 +361,8 @@ static inline void           Acb_NtkIncTravId( Acb_Ntk_t * p )
     for ( i = Vec_StrSize(&p->vObjType)-1; i > 0; i-- ) if ( !Acb_ObjType(p, i) ) {} else   
 #define Acb_NtkForEachNode( p, i )                                        \
     for ( i = 1; i < Vec_StrSize(&p->vObjType); i++ ) if ( !Acb_ObjType(p, i) || Acb_ObjIsCio(p, i) ) {} else   
+#define Acb_NtkForEachNodeSupp( p, i, nSuppSize )                         \
+    for ( i = 1; i < Vec_StrSize(&p->vObjType); i++ ) if ( !Acb_ObjType(p, i) || Acb_ObjIsCio(p, i) || Acb_ObjFaninNum(p, i) != nSuppSize ) {} else   
 #define Acb_NtkForEachNodeReverse( p, i )                                 \
     for ( i = Vec_StrSize(&p->vObjType)-1; i > 0; i-- ) if ( !Acb_ObjType(p, i) || Acb_ObjIsCio(p, i) ) {} else   
 #define Acb_NtkForEachObjType( p, Type, i )                               \
@@ -403,12 +405,35 @@ static inline int Acb_ObjFonNum( Acb_Ntk_t * p, int iObj )
         Count++;
     return Count;
 }
+static inline int Acb_ObjWhatFanin( Acb_Ntk_t * p, int iObj, int iFaninGiven )
+{
+    int k, iFanin, * pFanins;
+    Acb_ObjForEachFaninFast( p, iObj, pFanins, iFanin, k )
+        if ( iFanin == iFaninGiven )
+            return k;
+    return -1;
+}
 static inline void Acb_ObjAddFanin( Acb_Ntk_t * p, int iObj, int iFanin )
 {
     int * pFanins = Acb_ObjFanins( p, iObj );
     assert( pFanins[ 1 + pFanins[0] ] == -1 );
     pFanins[ 1 + pFanins[0]++ ] = iFanin;
 }
+static inline void Acb_ObjDeleteFaninIndex( Acb_Ntk_t * p, int iObj, int iFaninIndex )
+{
+    int i, * pFanins = Acb_ObjFanins( p, iObj );
+    pFanins[0]--;
+    for ( i = iFaninIndex; i < pFanins[0]; i++ )
+        pFanins[ 1 + i ] = pFanins[ 2 + i ];
+    pFanins[ 1 + pFanins[0] ] = -1;
+}
+static inline void Acb_ObjDeleteFanin( Acb_Ntk_t * p, int iObj, int iFanin )
+{
+    int * pFanins = Acb_ObjFanins( p, iObj );
+    int iFaninIndex = Acb_ObjWhatFanin( p, iObj, iFanin );
+    assert( pFanins[ 1 + iFaninIndex ] == iFanin );
+    Acb_ObjDeleteFaninIndex( p, iObj, iFaninIndex );
+}
 static inline void Acb_ObjAddFanins( Acb_Ntk_t * p, int iObj, Vec_Int_t * vFanins )
 {
     int i, iFanin;
@@ -495,12 +520,23 @@ static inline void Acb_ObjDelete( Acb_Ntk_t * p, int iObj )
     Acb_ObjForEachFon( p, iObj, i )
         Acb_ObjCleanType( p, i );
 }
+static inline void Acb_ObjAddFaninFanoutOne( Acb_Ntk_t * p, int iObj, int iFanin )
+{
+    Vec_IntPush( Vec_WecEntry(&p->vFanouts, iFanin), iObj );
+    Acb_ObjAddFanin( p, iObj, iFanin );
+}
 static inline void Acb_ObjAddFaninFanout( Acb_Ntk_t * p, int iObj )
 {
     int k, iFanin, * pFanins; 
     Acb_ObjForEachFaninFast( p, iObj, pFanins, iFanin, k )
         Vec_IntPush( Vec_WecEntry(&p->vFanouts, iFanin), iObj );
 }
+static inline void Acb_ObjRemoveFaninFanoutOne( Acb_Ntk_t * p, int iObj, int iFanin )
+{
+    int RetValue = Vec_IntRemove( Vec_WecEntry(&p->vFanouts, iFanin), iObj );
+    assert( RetValue );
+    Acb_ObjDeleteFanin( p, iObj, iFanin );
+}
 static inline void Acb_ObjRemoveFaninFanout( Acb_Ntk_t * p, int iObj )
 {
     int k, iFanin, * pFanins; 
@@ -510,6 +546,19 @@ static inline void Acb_ObjRemoveFaninFanout( Acb_Ntk_t * p, int iObj )
         assert( RetValue );
     }
 }
+static inline void Acb_ObjPatchFanin( Acb_Ntk_t * p, int iObj, int iFanin, int iFaninNew )
+{
+    int i, RetValue, * pFanins = Acb_ObjFanins( p, iObj );
+    assert( iFanin != iFaninNew );
+    for ( i = 0; i < pFanins[0]; i++ )
+        if ( pFanins[ 1 + i ] == iFanin )
+            pFanins[ 1 + i ] = iFaninNew;
+    if ( !Acb_NtkHasObjFanout(p) )
+        return;
+    RetValue = Vec_IntRemove( Vec_WecEntry(&p->vFanouts, iFanin), iObj );
+    assert( RetValue );
+    Vec_IntPush( Vec_WecEntry(&p->vFanouts, iFaninNew), iObj );
+}
 static inline void Acb_NtkCreateFanout( Acb_Ntk_t * p )
 {
     int iObj; 
diff --git a/src/base/acb/acbAbc.c b/src/base/acb/acbAbc.c
index 2b07a202..7b215a56 100644
--- a/src/base/acb/acbAbc.c
+++ b/src/base/acb/acbAbc.c
@@ -271,6 +271,28 @@ Abc_Ntk_t * Abc_NtkOptMfse( Abc_Ntk_t * pNtk, Acb_Par_t * pPars )
     return pNtkNew;
 }
 
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Abc_Ntk_t * Abc_NtkOptPush( Abc_Ntk_t * pNtk, int nLutSize, int fVerbose )
+{
+    extern void Acb_NtkPushLogic( Acb_Ntk_t * p, int nLutSize, int fVerbose );
+    Abc_Ntk_t * pNtkNew;
+    Acb_Ntk_t * p = Acb_NtkFromAbc( pNtk );
+    Acb_NtkPushLogic( p, nLutSize, fVerbose );
+    pNtkNew = Acb_NtkToAbc( pNtk, p );
+    Acb_ManFree( p->pDesign );
+    return pNtkNew;
+}
+
 ////////////////////////////////////////////////////////////////////////
 ///                       END OF FILE                                ///
 ////////////////////////////////////////////////////////////////////////
diff --git a/src/base/acb/acbMfs.c b/src/base/acb/acbMfs.c
index d8c6fb16..9fce00f8 100644
--- a/src/base/acb/acbMfs.c
+++ b/src/base/acb/acbMfs.c
@@ -1576,7 +1576,7 @@ cleanup:
 void Acb_NtkOpt( Acb_Ntk_t * pNtk, Acb_Par_t * pPars )
 {
     Acb_Mfs_t * pMan = Acb_MfsStart( pNtk, pPars );
-    //if ( pPars->fVerbose )
+    if ( pPars->fVerbose )
         printf( "%s-optimization parameters: TfiLev(I) = %d  TfoLev(O) = %d  WinMax(W) = %d  LutSize = %d\n", 
             pMan->pPars->fArea ? "Area" : "Delay", pMan->pPars->nTfiLevMax, pMan->pPars->nTfoLevMax, pMan->pPars->nWinNodeMax, pMan->pPars->nLutSize );
     Acb_NtkCreateFanout( pNtk );  // fanout data structure
@@ -1592,8 +1592,8 @@ void Acb_NtkOpt( Acb_Ntk_t * pNtk, Acb_Par_t * pPars )
                 if ( iObj < nNodes && !Vec_BitEntry(vVisited, iObj) && Acb_NtkObjMffcEstimate(pNtk, iObj) >= n )
                 {
                     pMan->nNodes++;
-                    if ( iObj != 103 )
-                        continue;
+                    //if ( iObj != 103 )
+                    //    continue;
                     //Acb_NtkOptNode( pMan, iObj );
                     while ( (RetValue = Acb_NtkOptNode(pMan, iObj)) && Acb_ObjFaninNum(pNtk, iObj) );                    
                     Vec_BitWriteEntry( vVisited, iObj, 1 );
@@ -1609,13 +1609,13 @@ void Acb_NtkOpt( Acb_Ntk_t * pNtk, Acb_Par_t * pPars )
             int iObj = Vec_QuePop(pNtk->vQue);
             if ( !Acb_ObjType(pNtk, iObj) )
                 continue;
-            if ( iObj != 103 )
-                continue;
+            //if ( iObj != 103 )
+            //    continue;
             //printf( "Trying node %4d (%4d) ", iObj, Value );
             Acb_NtkOptNode( pMan, iObj ); 
         }
     }
-    //if ( pPars->fVerbose )
+    if ( pPars->fVerbose )
     {
         pMan->timeTotal = Abc_Clock() - pMan->timeTotal;
         printf( "Node = %d  Win = %d (Ave = %d)  DivAve = %d   Change = %d  C = %d  N1 = %d  N2 = %d  N3 = %d   Over = %d  Str = %d  2Node = %d.\n", 
diff --git a/src/base/acb/acbPush.c b/src/base/acb/acbPush.c
new file mode 100644
index 00000000..01de31db
--- /dev/null
+++ b/src/base/acb/acbPush.c
@@ -0,0 +1,372 @@
+/**CFile****************************************************************
+
+  FileName    [acbPush.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Hierarchical word-level netlist.]
+
+  Synopsis    [Implementation of logic pushing.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - July 21, 2015.]
+
+  Revision    [$Id: acbPush.c,v 1.00 2014/11/29 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "acb.h"
+#include "misc/util/utilTruth.h"
+
+ABC_NAMESPACE_IMPL_START
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Pushing logic to the fanout.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Acb_ObjPushToFanout( Acb_Ntk_t * p, int iObj, int iFaninIndex, int iFanout )
+{
+    word c0, uTruthObjNew = 0, uTruthObj = Acb_ObjTruth( p, iObj ), Gate;
+    word c1, uTruthFanNew = 0, uTruthFan = Acb_ObjTruth( p, iFanout );
+    int DecType = Abc_TtCheckOutAnd( uTruthObj, iFaninIndex, &uTruthObjNew );
+    int iFanin = Acb_ObjFanin( p, iObj, iFaninIndex );
+    int iFanoutObjIndex = Acb_ObjWhatFanin( p, iFanout, iObj );
+    int iFanoutFaninIndex = Acb_ObjWhatFanin( p, iFanout, iFanin );
+    if ( iFanoutFaninIndex == -1 )
+        iFanoutFaninIndex = Acb_ObjFaninNum(p, iFanout); 
+    assert( !Acb_ObjIsCio(p, iObj) );
+    assert( !Acb_ObjIsCio(p, iFanout) );
+    assert( iFanoutFaninIndex >= 0 );
+    assert( iFaninIndex < Acb_ObjFaninNum(p, iObj) );
+    assert( Acb_ObjFanoutNum(p, iObj) == 1 );
+    // compute new function of the fanout
+    c0 = Abc_Tt6Cofactor0( uTruthFan, iFanoutObjIndex );
+    c1 = Abc_Tt6Cofactor1( uTruthFan, iFanoutObjIndex );
+    if ( DecType == 0 ) //  F = i * G
+        Gate =  s_Truths6[iFanoutFaninIndex] & s_Truths6[iFanoutObjIndex];
+    else if ( DecType == 1 ) //  F = ~i * G
+        Gate = ~s_Truths6[iFanoutFaninIndex] & s_Truths6[iFanoutObjIndex];
+    else if ( DecType == 2 ) //  F = ~i + G
+        Gate = ~s_Truths6[iFanoutFaninIndex] | s_Truths6[iFanoutObjIndex];
+    else if ( DecType == 3 ) //  F = i + G
+        Gate =  s_Truths6[iFanoutFaninIndex] | s_Truths6[iFanoutObjIndex];
+    else if ( DecType == 4 ) //  F = i # G
+        Gate =  s_Truths6[iFanoutFaninIndex] ^ s_Truths6[iFanoutObjIndex];
+    else assert( 0 );
+    uTruthFanNew = (~Gate & c0) | (Gate & c1);
+    // update functions
+    Vec_WrdWriteEntry( &p->vObjTruth, iObj, Abc_Tt6RemoveVar(uTruthObjNew, iFaninIndex) );
+    Vec_WrdWriteEntry( &p->vObjTruth, iFanout, uTruthFanNew );
+    // update fanins
+    Acb_ObjRemoveFaninFanoutOne( p, iObj, iFanin );
+    if ( iFanoutFaninIndex == Acb_ObjFaninNum(p, iFanout) ) // adding new
+        Acb_ObjAddFaninFanoutOne( p, iFanout, iFanin );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Pushing logic to the fanin.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Acb_ObjPushToFanin( Acb_Ntk_t * p, int iObj, int iFaninIndex2, int iFanin )
+{
+    word uTruthObjNew = 0, uTruthObj = Acb_ObjTruth( p, iObj );
+    word uTruthFanNew = 0, uTruthFan = Acb_ObjTruth( p, iFanin );
+    int iFaninIndex = Acb_ObjWhatFanin( p, iObj, iFanin );
+    int DecType = Abc_TtCheckDsdAnd( uTruthObj, iFaninIndex, iFaninIndex2, &uTruthObjNew );
+    int iFanin2 = Acb_ObjFanin( p, iObj, iFaninIndex2 );
+    int iFaninFaninIndex = Acb_ObjWhatFanin( p, iFanin, iFanin2 );
+    if ( iFaninFaninIndex == -1 )
+        iFaninFaninIndex = Acb_ObjFaninNum(p, iFanin); 
+    assert( !Acb_ObjIsCio(p, iObj) );
+    assert( !Acb_ObjIsCio(p, iFanin) );
+    assert( iFaninIndex  < Acb_ObjFaninNum(p, iObj) );
+    assert( iFaninIndex2 < Acb_ObjFaninNum(p, iObj) );
+    assert( iFaninIndex != iFaninIndex2 );
+    assert( Acb_ObjFanoutNum(p, iFanin) == 1 );
+    // compute new function of the fanout
+    if ( DecType == 0 )      //  i *  j
+        uTruthFanNew =  uTruthFan &  s_Truths6[iFaninFaninIndex];
+    else if ( DecType == 1 ) //  i * !j
+        uTruthFanNew = ~uTruthFan &  s_Truths6[iFaninFaninIndex];
+    else if ( DecType == 2 ) // !i *  j
+        uTruthFanNew =  uTruthFan & ~s_Truths6[iFaninFaninIndex];
+    else if ( DecType == 3 ) // !i * !j
+        uTruthFanNew = ~uTruthFan & ~s_Truths6[iFaninFaninIndex];
+    else if ( DecType == 4 ) //  i #  j
+        uTruthFanNew =  uTruthFan ^  s_Truths6[iFaninFaninIndex];
+    else assert( 0 );
+    // update functions
+    Vec_WrdWriteEntry( &p->vObjTruth, iObj, Abc_Tt6RemoveVar(uTruthObjNew, iFaninIndex2) );
+    Vec_WrdWriteEntry( &p->vObjTruth, iFanin, uTruthFanNew );
+    // update fanins
+    Acb_ObjRemoveFaninFanoutOne( p, iObj, iFanin2 );
+    if ( iFaninFaninIndex == Acb_ObjFaninNum(p, iFanin) ) // adding new
+        Acb_ObjAddFaninFanoutOne( p, iFanin, iFanin2 );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Removing constants, buffers, duplicated fanins.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int Acb_ObjFindNodeFanout( Acb_Ntk_t * p, int iObj )
+{
+    int i, iFanout;
+    Acb_ObjForEachFanout( p, iObj, iFanout, i )
+        if ( !Acb_ObjIsCio(p, iFanout) )
+            return iFanout;
+    return -1;
+}
+int Acb_ObjSuppMin_int( Acb_Ntk_t * p, int iObj )
+{
+    int k, iFanin, * pFanins;
+    word uTruth = Acb_ObjTruth( p, iObj );
+    Acb_ObjForEachFaninFast( p, iObj, pFanins, iFanin, k )
+    {
+        if ( Abc_Tt6HasVar(uTruth, k) )
+            continue;
+        Acb_ObjDeleteFaninIndex( p, iObj, k );
+        Vec_IntRemove( Vec_WecEntry(&p->vFanouts, iFanin), iObj );
+        Vec_WrdWriteEntry( &p->vObjTruth, iObj, Abc_Tt6RemoveVar(uTruth, k) );
+        return 1;
+    }
+    return 0;
+}
+void Acb_ObjSuppMin( Acb_Ntk_t * p, int iObj )
+{
+    while ( Acb_ObjSuppMin_int(p, iObj) );
+}
+void Acb_ObjRemoveDup( Acb_Ntk_t * p, int iObj, int i, int j )
+{
+    word c00, c11, uTruthNew, uTruth = Acb_ObjTruth( p, iObj );
+    assert( !Acb_ObjIsCio(p, iObj) );
+    assert( Acb_ObjFanin(p, iObj, i) == Acb_ObjFanin(p, iObj, j) );
+    c00 = Abc_Tt6Cofactor0( Abc_Tt6Cofactor0(uTruth, i), j );
+    c11 = Abc_Tt6Cofactor1( Abc_Tt6Cofactor1(uTruth, i), j );
+    uTruthNew = (~s_Truths6[i] & c00) | (s_Truths6[i] & c11);
+    Vec_WrdWriteEntry( &p->vObjTruth, iObj, Abc_Tt6RemoveVar(uTruthNew, j) );
+    Acb_ObjDeleteFaninIndex( p, iObj, j );
+    Vec_IntRemove( Vec_WecEntry(&p->vFanouts, iObj), Acb_ObjFanin(p, iObj, j) );
+    Acb_ObjSuppMin( p, iObj );
+}
+int Acb_ObjRemoveDupFanins_int( Acb_Ntk_t * p, int iObj )
+{
+    int i, k, * pFanins = Acb_ObjFanins( p, iObj );
+    for ( i = 0; i < pFanins[0]; i++ )
+    for ( k = i+1; k < pFanins[0]; k++ )
+    {
+        if ( pFanins[1+i] != pFanins[1+k] )
+            continue;
+        Acb_ObjRemoveDup( p, iObj, i, k );
+        return 1;
+    }
+    return 0;
+}
+void Acb_ObjRemoveDupFanins( Acb_Ntk_t * p, int iObj )
+{
+    assert( !Acb_ObjIsCio(p, iObj) );
+    while ( Acb_ObjRemoveDupFanins_int(p, iObj) );
+}
+void Acb_ObjRemoveConst( Acb_Ntk_t * p, int iObj )
+{
+    int iFanout;
+    word uTruth = Acb_ObjTruth( p, iObj );
+    assert( !Acb_ObjIsCio(p, iObj) );
+    assert( Acb_ObjFaninNum(p, iObj) == 0 );
+    assert( uTruth == 0 || ~uTruth == 0 );
+    while ( (iFanout = Acb_ObjFindNodeFanout(p, iObj)) >= 0 )
+    {
+        int iObjIndex = Acb_ObjWhatFanin( p, iFanout, iObj );
+        word uTruthF = Acb_ObjTruth( p, iFanout );
+        Acb_ObjRemoveFaninFanoutOne( p, iFanout, iObj );
+        uTruthF = (uTruth & 1) ? Abc_Tt6Cofactor1(uTruthF, iObjIndex) : Abc_Tt6Cofactor0(uTruthF, iObjIndex);
+        Vec_WrdWriteEntry( &p->vObjTruth, iFanout, Abc_Tt6RemoveVar(uTruthF, iObjIndex) );
+        Acb_ObjSuppMin( p, iFanout );
+    }
+    if ( Acb_ObjFanoutNum(p, iObj) == 0 )
+        Acb_ObjCleanType( p, iObj );
+}
+void Acb_ObjRemoveBufInv( Acb_Ntk_t * p, int iObj )
+{
+    int iFanout;
+    word uTruth = Acb_ObjTruth( p, iObj );
+    assert( !Acb_ObjIsCio(p, iObj) );
+    assert( Acb_ObjFaninNum(p, iObj) == 1 );
+    assert( uTruth == s_Truths6[0] || ~uTruth == s_Truths6[0] );
+    while ( (iFanout = Acb_ObjFindNodeFanout(p, iObj)) >= 0 )
+    {
+        int iFanin = Acb_ObjFanin( p, iObj, 0 );
+        int iObjIndex = Acb_ObjWhatFanin( p, iFanout, iObj );
+        Acb_ObjPatchFanin( p, iFanout, iObj, iFanin );
+        if ( uTruth & 1 ) // inv
+        {
+            word uTruthF = Acb_ObjTruth( p, iFanout );
+            Vec_WrdWriteEntry( &p->vObjTruth, iFanout, Abc_Tt6Flip(uTruthF, iObjIndex) );
+        }
+        Acb_ObjRemoveDupFanins( p, iFanout );
+    }
+    while ( (uTruth & 1) == 0 && Acb_ObjFanoutNum(p, iObj) > 0 )
+    {
+        int iFanin = Acb_ObjFanin( p, iObj, 0 );
+        int iFanout = Acb_ObjFanout( p, iObj, 0 );
+        assert( Acb_ObjIsCo(p, iFanout) );
+        Acb_ObjPatchFanin( p, iFanout, iObj, iFanin );
+    }
+    if ( Acb_ObjFanoutNum(p, iObj) == 0 )
+    {
+        Acb_ObjRemoveFaninFanout( p, iObj );
+        Acb_ObjRemoveFanins( p, iObj );
+        Acb_ObjCleanType( p, iObj );
+    }
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Check if the node can have its logic pushed.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int Acb_ObjFindFaninPushableIndex( Acb_Ntk_t * p, int iObj, int iFanIndex )
+{
+    int k, iFanin, * pFanins;
+    Acb_ObjForEachFaninFast( p, iObj, pFanins, iFanin, k )
+        if ( k != iFanIndex && Abc_TtCheckDsdAnd(Acb_ObjTruth(p, iObj), k, iFanIndex, NULL) >= 0 )
+            return k;
+    return -1;
+}
+static inline int Acb_ObjFindFanoutPushableIndex( Acb_Ntk_t * p, int iObj )
+{
+    int k, iFanin, * pFanins;
+    Acb_ObjForEachFaninFast( p, iObj, pFanins, iFanin, k )
+        if ( Abc_TtCheckOutAnd(Acb_ObjTruth(p, iObj), k, NULL) >= 0 )
+            return k;
+    return -1;
+}
+int Acb_ObjPushToFanins( Acb_Ntk_t * p, int iObj, int nLutSize )
+{
+    int k, k2, iFanin, * pFanins;
+    if ( Acb_ObjFaninNum(p, iObj) < 2 )
+        return 0;
+    Acb_ObjForEachFaninFast( p, iObj, pFanins, iFanin, k )
+    {
+        if ( Acb_ObjIsCi(p, iFanin) )
+            continue;
+        if ( Acb_ObjFanoutNum(p, iFanin) > 1 )
+            continue;
+        if ( Acb_ObjFaninNum(p, iFanin) == nLutSize )
+            continue;
+        if ( (k2 = Acb_ObjFindFaninPushableIndex(p, iObj, k)) == -1 )
+            continue;
+        //printf( "Object %4d : Pushing fanin %d (%d) into fanin %d.\n", iObj, Acb_ObjFanin(p, iObj, k2), k2, iFanin );
+        Acb_ObjPushToFanin( p, iObj, k2, iFanin );
+        return 1;
+    }
+    if ( Acb_ObjFaninNum(p, iObj) == 2 && Acb_ObjFanoutNum(p, iObj) == 1 )
+    {
+        int iFanout = Acb_ObjFanout( p, iObj, 0 );
+        if ( !Acb_ObjIsCo(p, iFanout) && Acb_ObjFaninNum(p, iFanout) < nLutSize )
+        {
+            k2 = Acb_ObjFindFanoutPushableIndex( p, iObj );
+            //printf( "Object %4d : Pushing fanin %d (%d) into fanout %d.\n", iObj, Acb_ObjFanin(p, iObj, k2), k2, iFanout );
+            Acb_ObjPushToFanout( p, iObj, k2, iFanout );
+            return 1;
+        }
+    }
+    return 0;
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Acb_NtkPushLogic( Acb_Ntk_t * p, int nLutSize, int fVerbose )
+{
+    int n = 0, iObj, nNodes = Acb_NtkNodeNum(p), nPushes = 0;
+    Acb_NtkCreateFanout( p );  // fanout data structure
+    Acb_NtkForEachNodeSupp( p, iObj, 0 )
+        Acb_ObjRemoveConst( p, iObj );
+    Acb_NtkForEachNodeSupp( p, iObj, 1 )
+        Acb_ObjRemoveBufInv( p, iObj );
+    for ( n = 2; n <= nLutSize; n++ )
+        Acb_NtkForEachNodeSupp( p, iObj, n )
+        {
+            while ( Acb_ObjPushToFanins(p, iObj, nLutSize) )
+                nPushes++;
+            if ( Acb_ObjFaninNum(p, iObj) == 1 )
+                Acb_ObjRemoveBufInv( p, iObj );
+        }
+    printf( "Saved %d nodes after %d pushes.\n", nNodes - Acb_NtkNodeNum(p), nPushes );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Pushing logic to the fanin.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Acb_NtkPushLogic2( Acb_Ntk_t * p, int nLutSize, int fVerbose )
+{
+    int iObj;
+    Acb_NtkCreateFanout( p );  // fanout data structure
+    Acb_NtkForEachObj( p, iObj )
+        if ( !Acb_ObjIsCio(p, iObj) )
+            break;
+    Acb_ObjPushToFanout( p, iObj, Acb_ObjFaninNum(p, iObj)-1, Acb_ObjFanout(p, iObj, 0) );
+//    Acb_ObjPushToFanin( p, Acb_ObjFanout(p, iObj, 0), Acb_ObjFaninNum(p, iObj)-1, iObj );
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/base/acb/module.make b/src/base/acb/module.make
index 06affeff..46294f9f 100644
--- a/src/base/acb/module.make
+++ b/src/base/acb/module.make
@@ -3,5 +3,6 @@ SRC +=    src/base/acb/acbAbc.c \
     src/base/acb/acbCom.c \
     src/base/acb/acbFunc.c \
     src/base/acb/acbMfs.c \
+    src/base/acb/acbPush.c \
     src/base/acb/acbSets.c \
     src/base/acb/acbUtil.c 
diff --git a/src/base/wlc/wlc.h b/src/base/wlc/wlc.h
index 7086cc9f..eff3acba 100644
--- a/src/base/wlc/wlc.h
+++ b/src/base/wlc/wlc.h
@@ -325,7 +325,7 @@ extern int            Wlc_NtkPdrAbs( Wlc_Ntk_t * p, Wlc_Par_t * pPars );
 /*=== wlcAbs2.c ========================================================*/
 extern int            Wlc_NtkAbsCore2( Wlc_Ntk_t * p, Wlc_Par_t * pPars );
 /*=== wlcBlast.c ========================================================*/
-extern Gia_Man_t *    Wlc_NtkBitBlast( Wlc_Ntk_t * p, Vec_Int_t * vBoxIds, int iOutput, int nRange, int fGiaSimple, int fAddOutputs, int fBooth, int fNoCleanup );
+extern Gia_Man_t *    Wlc_NtkBitBlast( Wlc_Ntk_t * p, Vec_Int_t * vBoxIds, int iOutput, int nRange, int fGiaSimple, int fAddOutputs, int fBooth, int fNoCleanup, int fCreateMiter );
 /*=== wlcCom.c ========================================================*/
 extern void           Wlc_SetNtk( Abc_Frame_t * pAbc, Wlc_Ntk_t * pNtk );
 /*=== wlcNtk.c ========================================================*/
diff --git a/src/base/wlc/wlcAbs.c b/src/base/wlc/wlcAbs.c
index d0ef1f07..a183fb5f 100644
--- a/src/base/wlc/wlcAbs.c
+++ b/src/base/wlc/wlcAbs.c
@@ -320,7 +320,7 @@ static Vec_Int_t * Wlc_NtkGetCoreSels( Gia_Man_t * pFrames, int nFrames, int fir
 
 static Gia_Man_t * Wlc_NtkUnrollWoCex(Wlc_Ntk_t * pChoice, int nFrames, int first_sel_pi, int num_sel_pis)
 {
-    Gia_Man_t * pGiaChoice = Wlc_NtkBitBlast( pChoice, NULL, -1, 0, 0, 0, 0, 0 );
+    Gia_Man_t * pGiaChoice = Wlc_NtkBitBlast( pChoice, NULL, -1, 0, 0, 0, 0, 0, 0 );
     Gia_Man_t * pFrames = NULL, * pGia;
     Gia_Obj_t * pObj, * pObjRi;
     int f, i;
@@ -366,7 +366,7 @@ static Gia_Man_t * Wlc_NtkUnrollWoCex(Wlc_Ntk_t * pChoice, int nFrames, int firs
 
 static Gia_Man_t * Wlc_NtkUnrollWithCex(Wlc_Ntk_t * pChoice, Abc_Cex_t * pCex, int nbits_old_pis, int num_sel_pis, int * p_num_ppis, int sel_pi_first, int fUsePPI) 
 {
-    Gia_Man_t * pGiaChoice = Wlc_NtkBitBlast( pChoice, NULL, -1, 0, 0, 0, 0, 0 );
+    Gia_Man_t * pGiaChoice = Wlc_NtkBitBlast( pChoice, NULL, -1, 0, 0, 0, 0, 0, 0 );
     int nbits_new_pis = Wlc_NtkNumPiBits( pChoice );
     int num_ppis = nbits_new_pis - nbits_old_pis - num_sel_pis;
     int num_undc_pis = Gia_ManPiNum(pGiaChoice) - nbits_new_pis;
@@ -560,7 +560,7 @@ Wlc_Ntk_t * Wlc_NtkIntroduceChoices( Wlc_Ntk_t * pNtk, Vec_Int_t * vBlacks, Vec_
 
 static Abc_Cex_t * Wlc_NtkCexIsReal( Wlc_Ntk_t * pOrig, Abc_Cex_t * pCex ) 
 {
-    Gia_Man_t * pGiaOrig = Wlc_NtkBitBlast( pOrig, NULL, -1, 0, 0, 0, 0, 0 );
+    Gia_Man_t * pGiaOrig = Wlc_NtkBitBlast( pOrig, NULL, -1, 0, 0, 0, 0, 0, 0 );
     int f, i;
     Gia_Obj_t * pObj, * pObjRi;
     Abc_Cex_t * pCexReal = Abc_CexAlloc( Gia_ManRegNum(pGiaOrig), Gia_ManPiNum(pGiaOrig), pCex->iFrame + 1 );
@@ -1401,7 +1401,7 @@ Aig_Man_t * Wla_ManBitBlast( Wla_Man_t * pWla, Wlc_Ntk_t * pAbs )
     Gia_Man_t * pTemp;
     Aig_Man_t * pAig;
 
-    pWla->pGia = Wlc_NtkBitBlast( pAbs, NULL, -1, 0, 0, 0, 0, 0 );
+    pWla->pGia = Wlc_NtkBitBlast( pAbs, NULL, -1, 0, 0, 0, 0, 0, 0 );
 
     // if the abstraction has flops with DC-init state,
     // new PIs were introduced by bit-blasting at the end of the PI list
@@ -1829,7 +1829,7 @@ int Wlc_NtkAbsCore( Wlc_Ntk_t * p, Wlc_Par_t * pPars )
 
             pAbs = Wlc_NtkAbs( p, pPars, vUnmark, &vPisNew, NULL, pPars->fVerbose );
         }
-        pGia = Wlc_NtkBitBlast( pAbs, NULL, -1, 0, 0, 0, 0, 0 );
+        pGia = Wlc_NtkBitBlast( pAbs, NULL, -1, 0, 0, 0, 0, 0, 0 );
 
         // if the abstraction has flops with DC-init state,
         // new PIs were introduced by bit-blasting at the end of the PI list
diff --git a/src/base/wlc/wlcAbs2.c b/src/base/wlc/wlcAbs2.c
index ff0092e6..4b2e6740 100644
--- a/src/base/wlc/wlcAbs2.c
+++ b/src/base/wlc/wlcAbs2.c
@@ -328,7 +328,7 @@ int Wlc_NtkAbsCore2( Wlc_Ntk_t * p, Wlc_Par_t * pPars )
 
         // get abstracted GIA and the set of pseudo-PIs (vPisNew)
         pAbs = Wlc_NtkAbs( p, pPars, vUnmark, &vPisNew, pPars->fVerbose );
-        pGia = Wlc_NtkBitBlast( pAbs, NULL, -1, 0, 0, 0, 0, 0 );
+        pGia = Wlc_NtkBitBlast( pAbs, NULL, -1, 0, 0, 0, 0, 0, 0 );
 
         // if the abstraction has flops with DC-init state,
         // new PIs were introduced by bit-blasting at the end of the PI list
diff --git a/src/base/wlc/wlcBlast.c b/src/base/wlc/wlcBlast.c
index 02cb2b1c..b2d0e287 100644
--- a/src/base/wlc/wlcBlast.c
+++ b/src/base/wlc/wlcBlast.c
@@ -868,14 +868,14 @@ void Wlc_BlastBooth( Gia_Man_t * pNew, int * pArgA, int * pArgB, int nArgA, int
   SeeAlso     []
 
 ***********************************************************************/
-Gia_Man_t * Wlc_NtkBitBlast( Wlc_Ntk_t * p, Vec_Int_t * vBoxIds, int iOutput, int nOutputRange, int fGiaSimple, int fAddOutputs, int fBooth, int fNoCleanup )
+Gia_Man_t * Wlc_NtkBitBlast( Wlc_Ntk_t * p, Vec_Int_t * vBoxIds, int iOutput, int nOutputRange, int fGiaSimple, int fAddOutputs, int fBooth, int fNoCleanup, int fCreateMiter )
 {
     int fVerbose = 0;
     int fUseOldMultiplierBlasting = 0;
     int fSkipBitRange = 0;
     Tim_Man_t * pManTime = NULL;
     Gia_Man_t * pTemp, * pNew, * pExtra = NULL;
-    Wlc_Obj_t * pObj;
+    Wlc_Obj_t * pObj, * pObj2;
     Vec_Int_t * vBits = &p->vBits, * vTemp0, * vTemp1, * vTemp2, * vRes, * vAddOutputs = NULL, * vAddObjs = NULL;
     int nBits = Wlc_NtkPrepareBits( p );
     int nRange, nRange0, nRange1, nRange2;
@@ -1211,6 +1211,31 @@ Gia_Man_t * Wlc_NtkBitBlast( Wlc_Ntk_t * p, Vec_Int_t * vBoxIds, int iOutput, in
             for ( k = 1; k < nRange; k++ )
                 Vec_IntPush( vRes, 0 );
         }
+        else if ( pObj->Type == WLC_OBJ_COMP_NOTEQU && Wlc_ObjFaninNum(pObj) > 2 )
+        {
+            // find the max range
+            int a, b, iRes = 1, nRangeMax = Abc_MaxInt( nRange0, nRange1 );
+            for ( k = 2; k < Wlc_ObjFaninNum(pObj); k++ )
+                nRangeMax = Abc_MaxInt( nRangeMax, Wlc_ObjRange( Wlc_NtkObj(p, Wlc_ObjFaninId(pObj, k)) ) );
+            // create pairwise distinct
+            for ( a = 0; a < Wlc_ObjFaninNum(pObj); a++ )
+            for ( b = a+1; b < Wlc_ObjFaninNum(pObj); b++ )
+            {
+                int nRange0 = Wlc_ObjRange( Wlc_NtkObj(p, Wlc_ObjFaninId(pObj, a)) );
+                int nRange1 = Wlc_ObjRange( Wlc_NtkObj(p, Wlc_ObjFaninId(pObj, b)) );
+                int * pFans0 = Vec_IntEntryP( vBits, Wlc_ObjCopy(p, Wlc_ObjFaninId(pObj, a)) );
+                int * pFans1 = Vec_IntEntryP( vBits, Wlc_ObjCopy(p, Wlc_ObjFaninId(pObj, b)) );
+                int * pArg0 = Wlc_VecLoadFanins( vTemp0, pFans0, nRange0, nRangeMax, 0 );
+                int * pArg1 = Wlc_VecLoadFanins( vTemp1, pFans1, nRange1, nRangeMax, 0 );
+                int iLit = 0;
+                for ( k = 0; k < nRangeMax; k++ )
+                    iLit = Gia_ManHashOr( pNew, iLit, Gia_ManHashXor(pNew, pArg0[k], pArg1[k]) ); 
+                iRes = Gia_ManHashAnd( pNew, iRes, iLit ); 
+            }
+            Vec_IntFill( vRes, 1, iRes );
+            for ( k = 1; k < nRange; k++ )
+                Vec_IntPush( vRes, 0 );
+        }
         else if ( pObj->Type == WLC_OBJ_COMP_EQU || pObj->Type == WLC_OBJ_COMP_NOTEQU )
         {
             int iLit = 0, nRangeMax = Abc_MaxInt( nRange0, nRange1 );
@@ -1363,38 +1388,91 @@ Gia_Man_t * Wlc_NtkBitBlast( Wlc_Ntk_t * p, Vec_Int_t * vBoxIds, int iOutput, in
     Vec_IntFree( vTemp2 );
     Vec_IntFree( vRes );
     // create COs
-    Wlc_NtkForEachCo( p, pObj, i )
+    if ( fCreateMiter )
     {
-        // skip all outputs except the given ones
-        if ( iOutput >= 0 && (i < iOutput || i >= iOutput + nOutputRange) )
-            continue;
-        // create additional PO literals
-        if ( vAddOutputs && pObj->fIsFi )
-        {
-            Vec_IntForEachEntry( vAddOutputs, iLit, k )
-                Gia_ManAppendCo( pNew, iLit );
-            printf( "Created %d additional POs for %d interesting internal word-level variables.\n", Vec_IntSize(vAddOutputs), Vec_IntSize(vAddObjs) );
-            Vec_IntFreeP( &vAddOutputs );
-        }
-        nRange = Wlc_ObjRange( pObj );
-        pFans0 = Vec_IntEntryP( vBits, Wlc_ObjCopy(p, Wlc_ObjId(p, pObj)) );
-        if ( fVerbose )
-            printf( "%s(%d) ", Wlc_ObjName(p, Wlc_ObjId(p, pObj)), Gia_ManCoNum(pNew) );
-        if ( Wlc_ObjRangeIsReversed(pObj) )
+        int nPairs = 0, nBits = 0;
+        assert( Wlc_NtkPoNum(p) % 2 == 0 );
+        Wlc_NtkForEachCo( p, pObj, i )
         {
-            for ( k = 0; k < nRange; k++ )
-                Gia_ManAppendCo( pNew, pFans0[nRange-1-k] );
+            if ( pObj->fIsFi )
+            {
+                nRange = Wlc_ObjRange( pObj );
+                pFans0 = Vec_IntEntryP( vBits, Wlc_ObjCopy(p, Wlc_ObjId(p, pObj)) );
+                if ( Wlc_ObjRangeIsReversed(pObj) )
+                {
+                    for ( k = 0; k < nRange; k++ )
+                        Gia_ManAppendCo( pNew, pFans0[nRange-1-k] );
+                }
+                else
+                {
+                    for ( k = 0; k < nRange; k++ )
+                        Gia_ManAppendCo( pNew, pFans0[k] );
+                }
+                nFFins += nRange;
+                continue;
+            }
+            pObj2   = Wlc_NtkCo( p, ++i );
+            nRange1 = Wlc_ObjRange( pObj );
+            nRange2 = Wlc_ObjRange( pObj2 );
+            assert( nRange1 == nRange2 );
+            pFans1  = Vec_IntEntryP( vBits, Wlc_ObjCopy(p, Wlc_ObjId(p, pObj)) );
+            pFans2  = Vec_IntEntryP( vBits, Wlc_ObjCopy(p, Wlc_ObjId(p, pObj2)) );
+            if ( Wlc_ObjRangeIsReversed(pObj) )
+            {
+                for ( k = 0; k < nRange1; k++ )
+                {
+                    Gia_ManAppendCo( pNew, pFans1[nRange1-1-k] );
+                    Gia_ManAppendCo( pNew, pFans2[nRange2-1-k] );
+                }
+            }
+            else
+            {
+                for ( k = 0; k < nRange1; k++ )
+                {
+                    Gia_ManAppendCo( pNew, pFans1[k] );
+                    Gia_ManAppendCo( pNew, pFans2[k] );
+                }
+            }
+            nPairs++;
+            nBits += nRange1;
         }
-        else
+        printf( "Derived a dual-output miter with %d pairs of bits belonging to %d pairs of word-level outputs.\n", nBits, nPairs );
+    }
+    else
+    {
+        Wlc_NtkForEachCo( p, pObj, i )
         {
-            for ( k = 0; k < nRange; k++ )
-                Gia_ManAppendCo( pNew, pFans0[k] );
+            // skip all outputs except the given ones
+            if ( iOutput >= 0 && (i < iOutput || i >= iOutput + nOutputRange) )
+                continue;
+            // create additional PO literals
+            if ( vAddOutputs && pObj->fIsFi )
+            {
+                Vec_IntForEachEntry( vAddOutputs, iLit, k )
+                    Gia_ManAppendCo( pNew, iLit );
+                printf( "Created %d additional POs for %d interesting internal word-level variables.\n", Vec_IntSize(vAddOutputs), Vec_IntSize(vAddObjs) );
+                Vec_IntFreeP( &vAddOutputs );
+            }
+            nRange = Wlc_ObjRange( pObj );
+            pFans0 = Vec_IntEntryP( vBits, Wlc_ObjCopy(p, Wlc_ObjId(p, pObj)) );
+            if ( fVerbose )
+                printf( "%s(%d) ", Wlc_ObjName(p, Wlc_ObjId(p, pObj)), Gia_ManCoNum(pNew) );
+            if ( Wlc_ObjRangeIsReversed(pObj) )
+            {
+                for ( k = 0; k < nRange; k++ )
+                    Gia_ManAppendCo( pNew, pFans0[nRange-1-k] );
+            }
+            else
+            {
+                for ( k = 0; k < nRange; k++ )
+                    Gia_ManAppendCo( pNew, pFans0[k] );
+            }
+            if ( pObj->fIsFi )
+                nFFins += nRange;
         }
-        if ( pObj->fIsFi )
-            nFFins += nRange;
+        if ( fVerbose )
+            printf( "\n" );
     }
-    if ( fVerbose )
-        printf( "\n" );
     //Vec_IntErase( vBits );
     //Vec_IntErase( &p->vCopies );
     // set the number of registers
diff --git a/src/base/wlc/wlcCom.c b/src/base/wlc/wlcCom.c
index 16ed29cc..abcb9e19 100644
--- a/src/base/wlc/wlcCom.c
+++ b/src/base/wlc/wlcCom.c
@@ -885,9 +885,9 @@ int Abc_CommandBlast( Abc_Frame_t * pAbc, int argc, char ** argv )
     Wlc_Ntk_t * pNtk = Wlc_AbcGetNtk(pAbc);
     Vec_Int_t * vBoxIds = NULL;
     Gia_Man_t * pNew = NULL;
-    int c, iOutput = -1, nOutputRange = 2, fGiaSimple = 0, fAddOutputs = 0, fMulti = 0, fBooth = 0, fVerbose  = 0;
+    int c, iOutput = -1, nOutputRange = 2, fGiaSimple = 0, fAddOutputs = 0, fMulti = 0, fBooth = 0, fCreateMiter = 0, fVerbose  = 0;
     Extra_UtilGetoptReset();
-    while ( ( c = Extra_UtilGetopt( argc, argv, "ORcombvh" ) ) != EOF )
+    while ( ( c = Extra_UtilGetopt( argc, argv, "ORcombdvh" ) ) != EOF )
     {
         switch ( c )
         {
@@ -925,6 +925,9 @@ int Abc_CommandBlast( Abc_Frame_t * pAbc, int argc, char ** argv )
         case 'b':
             fBooth ^= 1;
             break;
+        case 'd':
+            fCreateMiter ^= 1;
+            break;
         case 'v':
             fVerbose ^= 1;
             break;
@@ -951,7 +954,7 @@ int Abc_CommandBlast( Abc_Frame_t * pAbc, int argc, char ** argv )
         return 0;
     }
     // transform
-    pNew = Wlc_NtkBitBlast( pNtk, vBoxIds, iOutput, nOutputRange, fGiaSimple, fAddOutputs, fBooth, 0 );
+    pNew = Wlc_NtkBitBlast( pNtk, vBoxIds, iOutput, nOutputRange, fGiaSimple, fAddOutputs, fBooth, 0, fCreateMiter );
     Vec_IntFreeP( &vBoxIds );
     if ( pNew == NULL )
     {
@@ -961,7 +964,7 @@ int Abc_CommandBlast( Abc_Frame_t * pAbc, int argc, char ** argv )
     Abc_FrameUpdateGia( pAbc, pNew );
     return 0;
 usage:
-    Abc_Print( -2, "usage: %%blast [-OR num] [-combvh]\n" );
+    Abc_Print( -2, "usage: %%blast [-OR num] [-combdvh]\n" );
     Abc_Print( -2, "\t         performs bit-blasting of the word-level design\n" );
     Abc_Print( -2, "\t-O num : zero-based index of the first word-level PO to bit-blast [default = %d]\n", iOutput );
     Abc_Print( -2, "\t-R num : the total number of word-level POs to bit-blast [default = %d]\n", nOutputRange );
@@ -969,6 +972,7 @@ usage:
     Abc_Print( -2, "\t-o     : toggle using additional POs on the word-level boundaries [default = %s]\n", fAddOutputs? "yes": "no" );
     Abc_Print( -2, "\t-m     : toggle creating boxes for all multipliers in the design [default = %s]\n", fMulti? "yes": "no" );
     Abc_Print( -2, "\t-b     : toggle generating radix-4 Booth multipliers [default = %s]\n", fBooth? "yes": "no" );
+    Abc_Print( -2, "\t-d     : toggle creating dual-output miter [default = %s]\n", fCreateMiter? "yes": "no" );
     Abc_Print( -2, "\t-v     : toggle printing verbose information [default = %s]\n", fVerbose? "yes": "no" );
     Abc_Print( -2, "\t-h     : print the command usage\n");
     return 1;
diff --git a/src/base/wlc/wlcGraft.c b/src/base/wlc/wlcGraft.c
index 33de00c5..f1f55eb3 100644
--- a/src/base/wlc/wlcGraft.c
+++ b/src/base/wlc/wlcGraft.c
@@ -210,7 +210,7 @@ Wlc_Ntk_t * Wlc_NtkGraftMulti( Wlc_Ntk_t * p, int fVerbose )
     Gia_Obj_t * pObj;
     Vec_Int_t * vObjsLHS = Wlc_NtkCollectObjs( p, 0, &nMultiLHS );
     Vec_Int_t * vObjsRHS = Wlc_NtkCollectObjs( p, 1, &nMultiRHS );
-    Gia_Man_t * pGia = Wlc_NtkBitBlast( p, NULL, -1, 0, 0, 0, 0, 1 );
+    Gia_Man_t * pGia = Wlc_NtkBitBlast( p, NULL, -1, 0, 0, 0, 0, 1, 0 );
     Vec_Mem_t * vTtMem = Vec_MemAlloc( nWords, 10 );
     Vec_MemHashAlloc( vTtMem, 10000 );
 
@@ -540,7 +540,7 @@ int Sbc_ManWlcNodes( Wlc_Ntk_t * pNtk, Gia_Man_t * p, Vec_Int_t * vGia2Out, int
 void Sbc_ManDetectMultTest( Wlc_Ntk_t * pNtk, int fVerbose )
 {
     extern Vec_Int_t * Sdb_StoComputeCutsDetect( Gia_Man_t * pGia );
-    Gia_Man_t * p = Wlc_NtkBitBlast( pNtk, NULL, -1, 0, 0, 0, 0, 1 );
+    Gia_Man_t * p = Wlc_NtkBitBlast( pNtk, NULL, -1, 0, 0, 0, 0, 1, 0 );
     Vec_Int_t * vIns, * vGia2Out;
     int iObjFound = -1;
 //    Gia_Obj_t * pObj; int i;
diff --git a/src/base/wlc/wlcReadSmt.c b/src/base/wlc/wlcReadSmt.c
index 69a01ab0..230b34ad 100644
--- a/src/base/wlc/wlcReadSmt.c
+++ b/src/base/wlc/wlcReadSmt.c
@@ -331,7 +331,7 @@ static inline int Smt_PrsCreateNode( Wlc_Ntk_t * pNtk, int Type, int fSigned, in
           Type == WLC_OBJ_LOGIC_OR ||      // 29: logic OR
           Type == WLC_OBJ_LOGIC_XOR ||     // 30: logic XOR
           Type == WLC_OBJ_COMP_EQU ||      // 31: compare equal
-          Type == WLC_OBJ_COMP_NOTEQU ||   // 32: compare not equal
+//          Type == WLC_OBJ_COMP_NOTEQU ||   // 32: compare not equal -- bug fix
           Type == WLC_OBJ_COMP_LESS ||     // 33: compare less
           Type == WLC_OBJ_COMP_MORE ||     // 34: compare more
           Type == WLC_OBJ_COMP_LESSEQU ||  // 35: compare less or equal
diff --git a/src/base/wlc/wlcReadVer.c b/src/base/wlc/wlcReadVer.c
index 63a6926b..a829e0fd 100644
--- a/src/base/wlc/wlcReadVer.c
+++ b/src/base/wlc/wlcReadVer.c
@@ -1292,7 +1292,7 @@ void Io_ReadWordTest( char * pFileName )
         return;
     Wlc_WriteVer( pNtk, "test.v", 0, 0 );
 
-    pNew = Wlc_NtkBitBlast( pNtk, NULL, -1, 0, 0, 0, 0, 0 );
+    pNew = Wlc_NtkBitBlast( pNtk, NULL, -1, 0, 0, 0, 0, 0, 0 );
     Gia_AigerWrite( pNew, "test.aig", 0, 0 );
     Gia_ManStop( pNew );
 
diff --git a/src/base/wlc/wlcSim.c b/src/base/wlc/wlcSim.c
index 2ae3c86e..31a8a4a0 100644
--- a/src/base/wlc/wlcSim.c
+++ b/src/base/wlc/wlcSim.c
@@ -129,7 +129,7 @@ Vec_Ptr_t * Wlc_NtkSimulate( Wlc_Ntk_t * p, Vec_Int_t * vNodes, int nWords, int
 {
     Gia_Obj_t * pObj; 
     Vec_Ptr_t * vOne, * vRes;
-    Gia_Man_t * pGia = Wlc_NtkBitBlast( p, NULL, -1, 0, 0, 0, 0, 0 );
+    Gia_Man_t * pGia = Wlc_NtkBitBlast( p, NULL, -1, 0, 0, 0, 0, 0, 0 );
     Wlc_Obj_t * pWlcObj;
     int f, i, k, w, nBits, Counter = 0;
     // allocate simulation info for one timeframe