Updating LUT synthesis code.

5 files changed, 301 insertions, 46 deletions

diff --git a/src/aig/gia/giaGen.c b/src/aig/gia/giaGen.c
index 3c813d5c..cb56ef64 100644
--- a/src/aig/gia/giaGen.c
+++ b/src/aig/gia/giaGen.c
@@ -222,6 +222,8 @@ Vec_Wrd_t * Gia_ManSimulateWordsOut( Gia_Man_t * p, Vec_Wrd_t * vSimsIn )
     // set output sim info
     Gia_ManForEachCoId( p, Id, i )
         memcpy( Vec_WrdEntryP(vSimsOut, i*nWords), Vec_WrdEntryP(p->vSims, Id*nWords), sizeof(word)*nWords );
+    Vec_WrdFreeP( &p->vSims );
+    p->nSimWords = -1;
     return vSimsOut;
 }
 
diff --git a/src/aig/gia/giaMinLut.c b/src/aig/gia/giaMinLut.c
index 7d0ac8e1..a33f9710 100644
--- a/src/aig/gia/giaMinLut.c
+++ b/src/aig/gia/giaMinLut.c
@@ -78,18 +78,18 @@ void Vec_WrdReadText( char * pFileName, Vec_Wrd_t ** pvSimI, Vec_Wrd_t ** pvSimO
     for ( iLine = 0; fgets( pLine, 1000, pFile ); iLine++ )
     {
         for ( i = 0; i < nIns; i++ )
-            if ( pLine[i] == '1' )
+            if ( pLine[nIns-1-i] == '1' )
                 Abc_TtXorBit( Vec_WrdArray(vSimI) + i*nWords, iLine );
-            else assert( pLine[i] == '0' );
+            else assert( pLine[nIns-1-i] == '0' );
         for ( i = 0; i < nOuts; i++ )
-            if ( pLine[nIns+i] == '1' )
+            if ( pLine[nIns+nOuts-1-i] == '1' )
                 Abc_TtXorBit( Vec_WrdArray(vSimO) + i*nWords, iLine );
-            else assert( pLine[nIns+i] == '0' );
+            else assert( pLine[nIns+nOuts-1-i] == '0' );
     }
     fclose( pFile );
     *pvSimI = vSimI;
     *pvSimO = vSimO;
-    printf( "Read %d words of simulation data for %d inputs and %d outputs.\n", nWords, nIns, nOuts );
+    printf( "Read %d words of simulation data for %d inputs and %d outputs (padded %d zero-patterns).\n", nWords, nIns, nOuts, nWords*64-nLines );
 }
 void Gia_ManSimInfoTransform( int fSmall )
 {
@@ -115,43 +115,143 @@ void Gia_ManSimInfoTransform( int fSmall )
   SeeAlso     []
 
 ***********************************************************************/
-int Gia_ManSimInfoTry( Gia_Man_t * p, Vec_Wrd_t * vSimI, Vec_Wrd_t * vSimO )
+Vec_Wrd_t * Vec_WrdZoneExtract( int ZoneSize, Vec_Wrd_t * p, int iWord, int nWords )
+{
+    int z, nZones = Vec_WrdSize(p)/ZoneSize;
+    int w, Limit = Abc_MinInt( nWords, ZoneSize-iWord );
+    Vec_Wrd_t * pNew = Vec_WrdStart( nZones*nWords );
+    for ( z = 0; z < nZones; z++ )
+        for ( w = 0; w < Limit; w++ )
+            Vec_WrdWriteEntry( pNew, z*nWords + w, Vec_WrdEntry(p, z*ZoneSize + iWord + w) );
+    return pNew;
+}
+void Vec_WrdZoneInsert( Vec_Wrd_t * pNew, int ZoneSize, Vec_Wrd_t * p, int iWord, int nWords )
+{
+    int z, nZones = Vec_WrdSize(pNew)/ZoneSize;
+    int w, Limit = Abc_MinInt( nWords, ZoneSize-iWord );
+    for ( z = 0; z < nZones; z++ )
+        for ( w = 0; w < Limit; w++ )
+            Vec_WrdWriteEntry( pNew, z*ZoneSize + iWord + w, Vec_WrdEntry(p, z*nWords + w) );
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Gia_ManSimInfoPrintOne( Gia_Man_t * p, Vec_Wrd_t * vSimsIn, Vec_Wrd_t * vSimsOut, int nWords, int nPats )
+{
+    int Id, i, k;
+    for ( k = 0; k < nPats; k++ )
+    {
+        Gia_ManForEachCiId( p, Id, i )
+    //        printf( "%d", Vec_WrdEntry(p->vSims, p->nSimWords*Id) & 1 );
+            printf( "%d", (Vec_WrdEntry(vSimsIn,  nWords*i) >> k) & 1 );
+        printf( " " );
+        Gia_ManForEachCoId( p, Id, i )
+    //        printf( "%d", Vec_WrdEntry(p->vSims, p->nSimWords*Id) & 1 );
+            printf( "%d", (Vec_WrdEntry(vSimsOut, nWords*i) >> k) & 1 );
+        printf( "\n" );
+    }
+}
+Vec_Wrd_t * Gia_ManSimInfoTryOne( Gia_Man_t * p, Vec_Wrd_t * vSimI, int fPrint )
 {
     extern Vec_Wrd_t * Gia_ManSimulateWordsOut( Gia_Man_t * p, Vec_Wrd_t * vSimsIn );
     Vec_Wrd_t * vSimsOut = Gia_ManSimulateWordsOut( p, vSimI );
-    word * pSim0 = Vec_WrdArray(p->vSims);
-    int i, Count, nWords = Vec_WrdSize(vSimO) / Gia_ManCoNum(p);
-    Gia_Obj_t * pObj; 
-    assert( Vec_WrdSize(vSimI) / Gia_ManCiNum(p) == nWords );
+    int nWords = Vec_WrdSize(vSimI) / Gia_ManCiNum(p);
     assert( Vec_WrdSize(vSimI) % Gia_ManCiNum(p) == 0 );
-    assert( Vec_WrdSize(vSimO) % Gia_ManCoNum(p) == 0 );
-    Abc_TtClear( pSim0, nWords );
-    Gia_ManForEachCo( p, pObj, i )
+    if ( fPrint )
+        Gia_ManSimInfoPrintOne( p, vSimI, vSimsOut, nWords, 6 );
+    return vSimsOut;
+}
+int Gia_ManSimEvalOne( Gia_Man_t * p, Vec_Wrd_t * vSimO, Vec_Wrd_t * vSimO_new )
+{
+    int i, Count = 0, nWords = Vec_WrdSize(vSimO) / Gia_ManCoNum(p);
+    word * pSim0 = ABC_CALLOC( word, nWords );
+    assert( Vec_WrdSize(vSimO) == Vec_WrdSize(vSimO_new) );
+    for ( i = 0; i < Gia_ManCoNum(p); i++ )
     {
-        word * pSimImpl = Vec_WrdEntryP( vSimsOut, i * nWords );
-        word * pSimGold = Vec_WrdEntryP( vSimO,    i * nWords );
+        word * pSimGold = Vec_WrdEntryP( vSimO,     i * nWords );
+        word * pSimImpl = Vec_WrdEntryP( vSimO_new, i * nWords );
         Abc_TtOrXor( pSim0, pSimImpl, pSimGold, nWords );
     }
     Count = Abc_TtCountOnesVec( pSim0, nWords );
-    printf( "Number of failed patterns is %d (out of %d). The first one is %d\n", 
+    printf( "Number of failed patterns is %d (out of %d). The first one is %d.\n", 
         Count, 64*nWords, Abc_TtFindFirstBit2(pSim0, nWords) );
-    Vec_WrdFreeP( &p->vSims );
-    Vec_WrdFreeP( &vSimsOut );
-    p->nSimWords = -1;
+    ABC_FREE( pSim0 );
     return Count;
 }
+Vec_Wrd_t * Gia_ManSimInfoTry( Gia_Man_t * p, Vec_Wrd_t * vSimI )
+{
+    int nWords = Vec_WrdSize(vSimI) / Gia_ManCiNum(p);
+    int w, nWordsOne = 200, nWordBatches = (nWords + nWordsOne - 1)/nWordsOne;
+    Vec_Wrd_t * vSimO_new = Vec_WrdStart( nWords * Gia_ManCoNum(p) );
+    for ( w = 0; w < nWordBatches; w++ )
+    {
+        //int Value = printf( "%3d / %3d : ", w, nWordBatches );
+        Vec_Wrd_t * vSimI_ = Vec_WrdZoneExtract( nWords, vSimI, w*nWordsOne, nWordsOne );
+        Vec_Wrd_t * vSimO_ = Gia_ManSimInfoTryOne( p, vSimI_, 0 );
+        Vec_WrdZoneInsert( vSimO_new, nWords, vSimO_, w*nWordsOne, nWordsOne );
+        Vec_WrdFree( vSimI_ );
+        Vec_WrdFree( vSimO_ );
+        //Value = 0;
+    }
+    return vSimO_new;
+}
+int Gia_ManSimInfoEval( Gia_Man_t * p, Vec_Wrd_t * vSimO, Vec_Wrd_t * vSimO_new )
+{
+    int nResult = Gia_ManSimEvalOne(p, vSimO, vSimO_new);
+    Vec_WrdDumpBin( "temp.simo", vSimO_new, 1 );
+    printf( "Total errors = %d.  ", nResult );
+    printf( "Density of output patterns %6.4f.\n", (float)Abc_TtCountOnesVec(Vec_WrdArray(vSimO_new), Vec_WrdSize(vSimO_new))/(64*Vec_WrdSize(vSimO_new)) );
+    return nResult;
+}
 void Gia_ManSimInfoTryTest( Gia_Man_t * p, int fSmall )
 {
     abctime clk = Abc_Clock();
-    int nIns  = fSmall ? 32 : 64;
-    int nOuts = fSmall ? 10 : 35;
-    char * pFileNameI = fSmall ? "s.simi" : "l.simi";
-    char * pFileNameO = fSmall ? "s.simo" : "l.simo";
+    char * pFileNameI = fSmall ? "io_s.simi" : "io_l.simi";
+    char * pFileNameO = fSmall ? "io_s.simo" : "io_l.simo";
     Vec_Wrd_t * vSimI = Vec_WrdReadBin( pFileNameI, 1 );
     Vec_Wrd_t * vSimO = Vec_WrdReadBin( pFileNameO, 1 );
-    Gia_ManSimInfoTry( p, vSimI, vSimO );
+    Vec_Wrd_t * vSimO_new;
+    printf( "Density of input  patterns %6.4f.\n", (float)Abc_TtCountOnesVec(Vec_WrdArray(vSimI), Vec_WrdSize(vSimI))/(64*Vec_WrdSize(vSimI)) );
+    printf( "Density of output patterns %6.4f.\n", (float)Abc_TtCountOnesVec(Vec_WrdArray(vSimO), Vec_WrdSize(vSimO))/(64*Vec_WrdSize(vSimO)) );
+    vSimO_new = Gia_ManSimInfoTry( p, vSimI );
+    Gia_ManSimInfoEval( p, vSimO, vSimO_new );
     Vec_WrdFree( vSimI );
     Vec_WrdFree( vSimO );
+    Vec_WrdFree( vSimO_new );
+    Abc_PrintTime( 1, "Time", Abc_Clock() - clk );
+}
+void Gia_ManSimInfoPassTest( Gia_Man_t * p, char * pFileName, char * pFileName2, int fCompare )
+{
+    abctime clk = Abc_Clock();
+    if ( fCompare )
+    {
+        Vec_Wrd_t * vSim1 = Vec_WrdReadBin( pFileName,  1 );
+        Vec_Wrd_t * vSim2 = Vec_WrdReadBin( pFileName2, 1 );
+        printf( "Density of input  patterns %6.4f.\n", (float)Abc_TtCountOnesVec(Vec_WrdArray(vSim1), Vec_WrdSize(vSim1))/(64*Vec_WrdSize(vSim1)) );
+        printf( "Density of output patterns %6.4f.\n", (float)Abc_TtCountOnesVec(Vec_WrdArray(vSim2), Vec_WrdSize(vSim2))/(64*Vec_WrdSize(vSim2)) );
+        Gia_ManSimInfoEval( p, vSim1, vSim2 );
+        Vec_WrdFree( vSim1 );
+        Vec_WrdFree( vSim2 );
+    }
+    else
+    {
+        Vec_Wrd_t * vSimI = Vec_WrdReadBin( pFileName, 1 );
+        Vec_Wrd_t * vSimO = Gia_ManSimInfoTry( p, vSimI );
+        printf( "Density of input  patterns %6.4f.\n", (float)Abc_TtCountOnesVec(Vec_WrdArray(vSimI), Vec_WrdSize(vSimI))/(64*Vec_WrdSize(vSimI)) );
+        printf( "Density of output patterns %6.4f.\n", (float)Abc_TtCountOnesVec(Vec_WrdArray(vSimO), Vec_WrdSize(vSimO))/(64*Vec_WrdSize(vSimO)) );
+        Vec_WrdDumpBin( pFileName2, vSimO, 1 );
+        Vec_WrdFree( vSimI );
+        Vec_WrdFree( vSimO );
+    }
     Abc_PrintTime( 1, "Time", Abc_Clock() - clk );
 }
 
@@ -166,8 +266,76 @@ void Gia_ManSimInfoTryTest( Gia_Man_t * p, int fSmall )
   SeeAlso     []
 
 ***********************************************************************/
-void Gia_ManSimInfoPassTest( Gia_Man_t * p, int fSmall )
+int Gia_ManCountFraction( Gia_Man_t * p, Vec_Wrd_t * vSimI, Vec_Int_t * vSupp, int Thresh )
+{
+    int i, k, Id, nUsed = 0, nGood = 0;
+    int nWords = Vec_WrdSize(vSimI) / Gia_ManCiNum(p);
+    int nMints = 1 << Vec_IntSize(vSupp);
+    word ** pSims = ABC_ALLOC( word *, Vec_IntSize(vSupp) );
+    int * pCounts = ABC_CALLOC( int, nMints );
+    Vec_IntForEachEntry( vSupp, Id, i )
+        pSims[i] = Vec_WrdEntryP( vSimI, Id * nWords );
+    for ( k = 0; k < 64*nWords; k++ )
+    {
+        int iMint = 0;
+        for ( i = 0; i < Vec_IntSize(vSupp); i++ )
+            if ( Abc_TtGetBit(pSims[i], k) )
+                iMint |= 1 << i;
+        assert( iMint < nMints );
+        pCounts[iMint]++;
+    }
+    for ( k = 0; k < nMints; k++ )
+    {
+        nUsed += (pCounts[k] > 0);
+        nGood += (pCounts[k] > Thresh);
+        //printf( "%d ", pCounts[k] );
+    }
+    //printf( "\n" );
+    printf( "Total used %4d and good %4d (out of %4d).\n", nUsed, nGood, nMints ); 
+    ABC_FREE( pSims );
+    ABC_FREE( pCounts );
+    return nUsed;
+}
+void Gia_ManCollectSupp_rec( Gia_Man_t * p, int iObj, Vec_Int_t * vSupp )
+{
+    Gia_Obj_t * pObj;
+    if ( !iObj || Gia_ObjIsTravIdCurrentId(p, iObj) )
+        return;
+    Gia_ObjSetTravIdCurrentId(p, iObj);
+    pObj = Gia_ManObj( p, iObj );
+    if ( Gia_ObjIsCi(pObj) )
+    {
+        Vec_IntPush( vSupp, Gia_ObjCioId(pObj) );
+        return;
+    }
+    assert( Gia_ObjIsAnd(pObj) );
+    Gia_ManCollectSupp_rec( p, Gia_ObjFaninId0(pObj, iObj), vSupp );
+    Gia_ManCollectSupp_rec( p, Gia_ObjFaninId1(pObj, iObj), vSupp );
+}
+Vec_Int_t * Gia_ManCollectSupp( Gia_Man_t * p, int iOut, int nOuts )
+{
+    Vec_Int_t * vSupp = Vec_IntAlloc( 16 ); int i;
+    Gia_ManIncrementTravId( p );
+    for ( i = 0; i < nOuts; i++ )
+        Gia_ManCollectSupp_rec( p, Gia_ObjFaninId0p(p, Gia_ManCo(p, iOut+i)), vSupp );
+    return vSupp;
+}
+void Gia_ManSimInfoSynthOne( Gia_Man_t * p, Vec_Wrd_t * vSimI, int iOut, int nOuts, int Thresh )
 {
+    Vec_Int_t * vSupp = Gia_ManCollectSupp( p, iOut, nOuts );
+    printf( "Group %3d / %3d / %3d : Supp = %3d   ", iOut, nOuts, Gia_ManCoNum(p), Vec_IntSize(vSupp) );
+    Gia_ManCountFraction( p, vSimI, vSupp, Thresh );
+    Vec_IntFree( vSupp );
+}
+void Gia_ManSimInfoSynth( Gia_Man_t * p, char * pFileName, int GroupSize, int Thresh )
+{
+    Vec_Wrd_t * vSimI = Vec_WrdReadBin( pFileName, 1 );  
+    int g, nPats = 64*Vec_WrdSize(vSimI)/Gia_ManCiNum(p);
+    printf( "Density of input  patterns %6.4f.\n", (float)Abc_TtCountOnesVec(Vec_WrdArray(vSimI), Vec_WrdSize(vSimI))/(64*Vec_WrdSize(vSimI)) );
+    printf( "The number of patterns %d with threshold %d (%6.2f %%).\n", nPats, Thresh, 100.0*Thresh/nPats );
+    for ( g = 0; g < Gia_ManCoNum(p); g += GroupSize )
+        Gia_ManSimInfoSynthOne( p, vSimI, g, GroupSize, Thresh );
+    Vec_WrdFree( vSimI );
 }
 
 /**Function*************************************************************
diff --git a/src/base/abci/abc.c b/src/base/abci/abc.c
index 15a4857b..ae97e4dd 100644
--- a/src/base/abci/abc.c
+++ b/src/base/abci/abc.c
@@ -486,6 +486,7 @@ static int Abc_CommandAbc9Pack               ( Abc_Frame_t * pAbc, int argc, cha
 static int Abc_CommandAbc9Edge               ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandAbc9SatLut             ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandAbc9MinLut             ( Abc_Frame_t * pAbc, int argc, char ** argv );
+static int Abc_CommandAbc9MinSim             ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandAbc9Unmap              ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandAbc9Struct             ( Abc_Frame_t * pAbc, int argc, char ** argv );
 static int Abc_CommandAbc9Trace              ( Abc_Frame_t * pAbc, int argc, char ** argv );
@@ -1210,6 +1211,7 @@ void Abc_Init( Abc_Frame_t * pAbc )
     Cmd_CommandAdd( pAbc, "ABC9",         "&edge",         Abc_CommandAbc9Edge,         0 );
     Cmd_CommandAdd( pAbc, "ABC9",         "&satlut",       Abc_CommandAbc9SatLut,       0 );
     Cmd_CommandAdd( pAbc, "ABC9",         "&minlut",       Abc_CommandAbc9MinLut,       0 );
+    Cmd_CommandAdd( pAbc, "ABC9",         "&minsim",       Abc_CommandAbc9MinSim,       0 );
     Cmd_CommandAdd( pAbc, "ABC9",         "&unmap",        Abc_CommandAbc9Unmap,        0 );
     Cmd_CommandAdd( pAbc, "ABC9",         "&struct",       Abc_CommandAbc9Struct,       0 );
     Cmd_CommandAdd( pAbc, "ABC9",         "&trace",        Abc_CommandAbc9Trace,        0 );
@@ -40825,11 +40827,13 @@ usage:
 ***********************************************************************/
 int Abc_CommandAbc9MinLut( Abc_Frame_t * pAbc, int argc, char ** argv )
 {
-    extern Gia_Man_t * Gia_ManPerformMinLut( Gia_Man_t * p, int GroupSize, int LutSize, int fVerbose );
-    Gia_Man_t * pTemp;
-    int c, LutSize = 6, GroupSize = 3, fVerbose = 0;
+    extern void Gia_ManSimInfoSynth( Gia_Man_t * p, char * pFileName, int GroupSize, int Thresh );
+    //extern Gia_Man_t * Gia_ManPerformMinLut( Gia_Man_t * p, int GroupSize, int LutSize, int fVerbose );
+    //Gia_Man_t * pTemp;
+    char * pFileName = NULL;
+    int c, LutSize = 6, GroupSize = 3, Limit = 0, fVerbose = 0;
     Extra_UtilGetoptReset();
-    while ( ( c = Extra_UtilGetopt( argc, argv, "KGvh" ) ) != EOF )
+    while ( ( c = Extra_UtilGetopt( argc, argv, "KGLvh" ) ) != EOF )
     {
         switch ( c )
         {
@@ -40851,6 +40855,15 @@ int Abc_CommandAbc9MinLut( Abc_Frame_t * pAbc, int argc, char ** argv )
             GroupSize = atoi(argv[globalUtilOptind]);
             globalUtilOptind++;
             break;
+        case 'L':
+            if ( globalUtilOptind >= argc )
+            {
+                Abc_Print( -1, "Command line switch \"-L\" should be followed by a positive integer.\n" );
+                goto usage;
+            }
+            Limit = atoi(argv[globalUtilOptind]);
+            globalUtilOptind++;
+            break;
         case 'v':
             fVerbose ^= 1;
             break;
@@ -40864,17 +40877,86 @@ int Abc_CommandAbc9MinLut( Abc_Frame_t * pAbc, int argc, char ** argv )
         Abc_Print( -1, "Empty GIA network.\n" );
         return 1;
     }
-    pTemp = Gia_ManPerformMinLut( pAbc->pGia, GroupSize, LutSize, fVerbose );
+    if ( argc == globalUtilOptind + 1 )
+    {
+        FILE * pFile = fopen( argv[globalUtilOptind], "rb" );
+        if ( pFile == NULL )
+        {
+            Abc_Print( -1, "Abc_CommandAbc9BCore(): Cannot open file \"%s\" for writing the proof.\n", argv[globalUtilOptind] );
+            return 0;
+        }
+        fclose( pFile );
+        pFileName = argv[globalUtilOptind];
+    }
+    //pTemp = Gia_ManPerformMinLut( pAbc->pGia, GroupSize, LutSize, fVerbose );
     //Abc_FrameUpdateGia( pAbc, pTemp );
+    Gia_ManSimInfoSynth( pAbc->pGia, pFileName, GroupSize, Limit );
     return 0;
 
 usage:
-    Abc_Print( -2, "usage: &minlut [-KG num] [-vh]\n" );
+    Abc_Print( -2, "usage: &minlut [-KGL num] [-vh] <file>\n" );
     Abc_Print( -2, "\t           performs specialized LUT mapping\n" );
-    Abc_Print( -2, "\t-K num   : the LUT size for mapping [default = %d]\n", LutSize );
-    Abc_Print( -2, "\t-G num   : the output group size [default = %d]\n",    GroupSize );
-    Abc_Print( -2, "\t-v       : toggles verbose output [default = %s]\n",   fVerbose? "yes": "no" );
+    Abc_Print( -2, "\t-K num   : the LUT size for mapping [default = %d]\n",      LutSize );
+    Abc_Print( -2, "\t-G num   : the output group size [default = %d]\n",         GroupSize );
+    Abc_Print( -2, "\t-L num   : the limit when patterns count [default = %d]\n", Limit );
+    Abc_Print( -2, "\t-v       : toggles verbose output [default = %s]\n",        fVerbose? "yes": "no" );
+    Abc_Print( -2, "\t-h       : prints the command usage\n");
+    Abc_Print( -2, "\t<file>   : file name with simulation information\n");
+    return 1;
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Abc_CommandAbc9MinSim( Abc_Frame_t * pAbc, int argc, char ** argv )
+{
+    extern void Gia_ManSimInfoPassTest( Gia_Man_t * p, char * pFileName, char * pFileName2, int fCompare );
+    int c, fCompare = 0, fVerbose = 0;
+    Extra_UtilGetoptReset();
+    while ( ( c = Extra_UtilGetopt( argc, argv, "cvh" ) ) != EOF )
+    {
+        switch ( c )
+        {
+        case 'c':
+            fCompare ^= 1;
+            break;
+        case 'v':
+            fVerbose ^= 1;
+            break;
+        case 'h':
+        default:
+            goto usage;
+        }
+    }
+    if ( pAbc->pGia == NULL )
+    {
+        Abc_Print( -1, "Empty GIA network.\n" );
+        return 1;
+    }
+    if ( argc != globalUtilOptind + 2 )
+    {
+        Abc_Print( -1, "Expecting two file names on the command line.\n" );
+        return 1;
+    }
+    Gia_ManSimInfoPassTest( pAbc->pGia, argv[globalUtilOptind], argv[globalUtilOptind+1], fCompare );
+    return 0;
+
+usage:
+    Abc_Print( -2, "usage: &minsim [-cvh] <file> <file2>\n" );
+    Abc_Print( -2, "\t           performs specialized AIG simulation\n" );
+    Abc_Print( -2, "\t-c       : toggles comparing simulation patterns [default = %s]\n",  fCompare? "yes": "no" );
+    Abc_Print( -2, "\t-v       : toggles verbose output [default = %s]\n",                 fVerbose? "yes": "no" );
     Abc_Print( -2, "\t-h       : prints the command usage\n");
+    Abc_Print( -2, "\t<file>   : file name with simulation information\n");
+    Abc_Print( -2, "\t<file2>  : file name with simulation information\n");
     return 1;
 }
 
diff --git a/src/base/io/ioWriteBench.c b/src/base/io/ioWriteBench.c
index 81d64582..23de719e 100644
--- a/src/base/io/ioWriteBench.c
+++ b/src/base/io/ioWriteBench.c
@@ -259,7 +259,7 @@ int Io_WriteBenchLutOneNode( FILE * pFile, Abc_Obj_t * pNode, Vec_Int_t * vTruth
     int i, nFanins;
     assert( Abc_ObjIsNode(pNode) );
     nFanins = Abc_ObjFaninNum(pNode);
-    assert( nFanins <= 8 );
+    assert( nFanins <= 15 );
     // compute the truth table
     pTruth = Hop_ManConvertAigToTruth( (Hop_Man_t *)pNode->pNtk->pManFunc, Hop_Regular((Hop_Obj_t *)pNode->pData), nFanins, vTruth, 0 );
     if ( Hop_IsComplement((Hop_Obj_t *)pNode->pData) )
diff --git a/src/misc/vec/vecWrd.h b/src/misc/vec/vecWrd.h
index 9fa82f2d..b0123453 100644
--- a/src/misc/vec/vecWrd.h
+++ b/src/misc/vec/vecWrd.h
@@ -1368,24 +1368,27 @@ static inline Vec_Wrd_t * Vec_WrdReadBin( char * pFileName, int fVerbose )
     }
     fseek( pFile, 0, SEEK_END );
     nSize = ftell( pFile );
-    if ( nSize % 8 > 0 )
+    if ( nSize == 0 )
     {
-        printf( "Cannot read file with simulation data that is not aligned at 8 bytes (remainder = %d).\n", nSize % 8 );
+        printf( "The input file is empty.\n" );
         fclose( pFile );
         return NULL;
     }
-    else
+    if ( nSize % 8 > 0 )
     {
-        rewind( pFile );
-        p = Vec_WrdStart( nSize/8 );
-        RetValue = fread( Vec_WrdArray(p), 1, nSize, pFile );
+        printf( "Cannot read file with simulation data that is not aligned at 8 bytes (remainder = %d).\n", nSize % 8 );
         fclose( pFile );
-        if ( RetValue != nSize )
-            printf( "Error reading data from file.\n" );
-        if ( fVerbose )
-            printf( "Read %d words of simulation data from file \"%s\".\n", nSize/8, pFileName );
-        return p;
+        return NULL;
     }
+    rewind( pFile );
+    p = Vec_WrdStart( nSize/8 );
+    RetValue = fread( Vec_WrdArray(p), 1, nSize, pFile );
+    fclose( pFile );
+    if ( RetValue != nSize )
+        printf( "Error reading data from file.\n" );
+    if ( fVerbose )
+        printf( "Read %d words of simulation data from file \"%s\".\n", nSize/8, pFileName );
+    return p;
 }
 
 ABC_NAMESPACE_HEADER_END