2 files changed, 62 insertions, 18 deletions

diff --git a/src/base/abci/abcNpn.c b/src/base/abci/abcNpn.c
index d2cac715..8335edda 100644
--- a/src/base/abci/abcNpn.c
+++ b/src/base/abci/abcNpn.c
@@ -181,7 +181,7 @@ void Abc_TruthNpnPerform( Abc_TtStore_t * p, int NpnType, int fVerbose )
     char pCanonPerm[16];
     unsigned uCanonPhase=0;
     abctime clk = Abc_Clock();
-    int i, nClasses = -1;
+    int i;
 
     char * pAlgoName = NULL;
     if ( NpnType == 0 )
@@ -309,12 +309,12 @@ void Abc_TruthNpnPerform( Abc_TtStore_t * p, int NpnType, int fVerbose )
 //                Extra_PrintHex( stdout, (unsigned *)p->pFuncs[i], p->nVars ), Abc_TruthNpnPrint(NULL, uCanonPhase, p->nVars), printf( "\n" );
                 printf( "\n" );
         }
-        nClasses = Abc_TtManNumClasses( pMan );
+        // nClasses = Abc_TtManNumClasses( pMan );
         Abc_TtManStop( pMan );
     }
     else assert( 0 );
     clk = Abc_Clock() - clk;
-    printf( "Classes =%9d  ", nClasses == -1 ? Abc_TruthNpnCountUnique(p) : nClasses );
+    printf( "Classes =%9d  ", Abc_TruthNpnCountUnique(p) );
     Abc_PrintTime( 1, "Time", clk );
 }
 
diff --git a/src/opt/dau/dauCanon.c b/src/opt/dau/dauCanon.c
index dab214bb..c6ac8288 100644
--- a/src/opt/dau/dauCanon.c
+++ b/src/opt/dau/dauCanon.c
@@ -1059,8 +1059,27 @@ unsigned Abc_TtCanonicizePhase( word * pTruth, int nVars )
 struct Abc_TtMan_t_
 {
     Vec_Mem_t *   vTtMem[TT_NUM_TABLES];   // truth table memory and hash tables
+    Vec_Int_t **  vRepres;                 // pointers to the representatives from the last hierarchical level
 };
 
+Vec_Int_t ** Abc_TtRepresStart() {
+    Vec_Int_t ** vRepres = ABC_ALLOC(Vec_Int_t *, TT_NUM_TABLES - 1);
+    int i;
+    // create a list of pointers for each level of the hierarchy
+    for (i = 0; i < (TT_NUM_TABLES - 1); i++) {
+        vRepres[i] = Vec_IntAlloc(1);
+    }
+    return vRepres;
+}
+
+void Abc_TtRepresStop(Vec_Int_t ** vRepres) {
+    int i;
+    for (i = 0; i < (TT_NUM_TABLES - 1); i++) {
+        Vec_IntFree(vRepres[i]);
+    }
+    ABC_FREE( vRepres );
+}
+
 Abc_TtMan_t * Abc_TtManStart( int nVars )
 {
     Abc_TtMan_t * p = ABC_CALLOC( Abc_TtMan_t, 1 );
@@ -1070,6 +1089,7 @@ Abc_TtMan_t * Abc_TtManStart( int nVars )
         p->vTtMem[i] = Vec_MemAlloc( nWords, 12 );
         Vec_MemHashAlloc( p->vTtMem[i], 10000 );
     }
+    p->vRepres = Abc_TtRepresStart();
     return p;
 }
 void Abc_TtManStop( Abc_TtMan_t * p )
@@ -1080,6 +1100,7 @@ void Abc_TtManStop( Abc_TtMan_t * p )
         Vec_MemHashFree( p->vTtMem[i] );
         Vec_MemFreeP( &p->vTtMem[i] );
     }
+    Abc_TtRepresStop(p->vRepres);
     ABC_FREE( p );
 }
 int Abc_TtManNumClasses( Abc_TtMan_t * p )
@@ -1096,6 +1117,9 @@ unsigned Abc_TtCanonicizeHie( Abc_TtMan_t * p, word * pTruthInit, int nVars, cha
     int nOnes, nWords = Abc_TtWordNum( nVars );
     int i, k, truthId;
     int * pSpot;
+    int vTruthId[TT_NUM_TABLES-1];
+    int fLevelFound;
+    word * pRepTruth;
     assert( nVars <= 16 );
 
     Abc_TtCopy( pTruth, pTruthInit, nWords, 0 );
@@ -1113,9 +1137,11 @@ unsigned Abc_TtCanonicizeHie( Abc_TtMan_t * p, word * pTruthInit, int nVars, cha
     }
     // check cache
     pSpot = Vec_MemHashLookup( p->vTtMem[0], pTruth );
-    if ( *pSpot != -1 )
-        return 0;
-    truthId = Vec_MemHashInsert( p->vTtMem[0], pTruth );
+    if ( *pSpot != -1 ) {
+        fLevelFound = 0;
+        goto end_repres;
+    }
+    vTruthId[0] = Vec_MemHashInsert( p->vTtMem[0], pTruth );
 
     // normalize phase
     Abc_TtCountOnesInCofs( pTruth, nVars, pStore );
@@ -1130,9 +1156,11 @@ unsigned Abc_TtCanonicizeHie( Abc_TtMan_t * p, word * pTruthInit, int nVars, cha
     }
     // check cache
     pSpot = Vec_MemHashLookup( p->vTtMem[1], pTruth );
-    if ( *pSpot != -1 )
-        return 0;
-    truthId = Vec_MemHashInsert( p->vTtMem[1], pTruth );
+    if ( *pSpot != -1 ) {
+        fLevelFound = 1;
+        goto end_repres;
+    }
+    vTruthId[1] = Vec_MemHashInsert( p->vTtMem[1], pTruth );
 
     // normalize permutation
     {
@@ -1157,9 +1185,11 @@ unsigned Abc_TtCanonicizeHie( Abc_TtMan_t * p, word * pTruthInit, int nVars, cha
     }
     // check cache
     pSpot = Vec_MemHashLookup( p->vTtMem[2], pTruth );
-    if ( *pSpot != -1 )
-        return 0;
-    truthId = Vec_MemHashInsert( p->vTtMem[2], pTruth );
+    if ( *pSpot != -1 ) {
+        fLevelFound = 2;
+        goto end_repres;
+    }
+    vTruthId[2] = Vec_MemHashInsert( p->vTtMem[2], pTruth );
 
     // iterate TT permutations for tied variables
     for ( k = 0; k < 5; k++ )
@@ -1179,9 +1209,11 @@ unsigned Abc_TtCanonicizeHie( Abc_TtMan_t * p, word * pTruthInit, int nVars, cha
     }
     // check cache
     pSpot = Vec_MemHashLookup( p->vTtMem[3], pTruth );
-    if ( *pSpot != -1 )
-        return 0;
-    truthId = Vec_MemHashInsert( p->vTtMem[3], pTruth );
+    if ( *pSpot != -1 ) {
+        fLevelFound = 3;
+        goto end_repres;
+    }
+    vTruthId[3] = Vec_MemHashInsert( p->vTtMem[3], pTruth );
 
     // perform exact NPN using groups
     if ( fExact ) {
@@ -1224,9 +1256,21 @@ unsigned Abc_TtCanonicizeHie( Abc_TtMan_t * p, word * pTruthInit, int nVars, cha
     }
     // check cache
     pSpot = Vec_MemHashLookup( p->vTtMem[4], pTruth );
-    if ( *pSpot != -1 )
-        return 0;
-    truthId = Vec_MemHashInsert( p->vTtMem[4], pTruth );
+    fLevelFound = 4;
+    if ( *pSpot != -1 ) {
+        goto end_repres;
+    }
+    *pSpot = Vec_MemHashInsert( p->vTtMem[4], pTruth );
+
+end_repres:
+    // return the class representative
+    if(fLevelFound < (TT_NUM_TABLES - 1))
+        truthId = Vec_IntEntry(p->vRepres[fLevelFound], *pSpot);
+    else truthId = *pSpot;
+    for(i = 0; i < fLevelFound; i++)
+        Vec_IntSetEntry(p->vRepres[i], vTruthId[i], truthId);
+    pRepTruth = Vec_MemReadEntry(p->vTtMem[TT_NUM_TABLES-1], truthId);
+    Abc_TtCopy( pTruthInit, pRepTruth, nWords, 0 );
 
     return 0;
 }