Imporvements to 'eliminate'.

2 files changed, 40 insertions, 8 deletions

diff --git a/src/base/abc/abcMinBase.c b/src/base/abc/abcMinBase.c
index 1c913eea..84cf5cb3 100644
--- a/src/base/abc/abcMinBase.c
+++ b/src/base/abc/abcMinBase.c
@@ -578,6 +578,22 @@ int Abc_NodeCollapse1( Abc_Obj_t * pFanin, Abc_Obj_t * pFanout, Vec_Ptr_t * vFan
     Abc_NtkDeleteObj_rec( pFanout, 1 );
     return 1;
 }
+int Abc_NodeIsExor( Abc_Obj_t * pNode )
+{
+    Hop_Man_t * pMan;
+    word Truth;
+    if ( Abc_ObjFaninNum(pNode) < 3 || Abc_ObjFaninNum(pNode) > 6 )
+        return 0;
+    pMan = (Hop_Man_t *)pNode->pNtk->pManFunc;
+    Truth = Hop_ManComputeTruth6( pMan, (Hop_Obj_t *)pNode->pData, Abc_ObjFaninNum(pNode) );
+    if ( Truth == 0x6666666666666666 || Truth == 0x9999999999999999 || 
+         Truth == 0x9696969696969696 || Truth == 0x6969696969696969 || 
+         Truth == 0x6996699669966996 || Truth == 0x9669966996699669 || 
+         Truth == 0x9669699696696996 || Truth == 0x6996966969969669 ||
+         Truth == 0x6996966996696996 || Truth == 0x9669699669969669 )
+         return 1;
+    return 0;
+}
 int Abc_NtkEliminate1One( Abc_Ntk_t * pNtk, int ElimValue, int nMaxSize, int fReverse, int fVerbose )
 {
     Vec_Ptr_t * vFanouts, * vFanins, * vNodes;
@@ -607,6 +623,8 @@ int Abc_NtkEliminate1One( Abc_Ntk_t * pNtk, int ElimValue, int nMaxSize, int fRe
             continue;
         if ( Abc_ObjFaninNum(pNode) > nMaxSize )
             continue;
+        if ( Abc_NodeIsExor(pNode) )
+            continue;
         // skip nodes with more than one fanout
 //        if ( Abc_ObjFanoutNum(pNode) != 1 ) 
 //            continue;
@@ -642,10 +660,10 @@ int Abc_NtkEliminate1One( Abc_Ntk_t * pNtk, int ElimValue, int nMaxSize, int fRe
     ABC_FREE( pPermFanout );
     return 1;
 }
-int Abc_NtkEliminate1( Abc_Ntk_t * pNtk, int ElimValue, int nMaxSize, int fReverse, int fVerbose )
+int Abc_NtkEliminate1( Abc_Ntk_t * pNtk, int ElimValue, int nMaxSize, int nIterMax, int fReverse, int fVerbose )
 {
     int i;
-    for ( i = 0; i < 3; i++ )
+    for ( i = 0; i < nIterMax; i++ )
     {
         int nNodes = Abc_NtkNodeNum(pNtk);
 //        printf( "%d ", nNodes );
diff --git a/src/base/abci/abc.c b/src/base/abci/abc.c
index 73e96054..84736382 100644
--- a/src/base/abci/abc.c
+++ b/src/base/abci/abc.c
@@ -3746,23 +3746,25 @@ usage:
 int Abc_CommandEliminate( Abc_Frame_t * pAbc, int argc, char ** argv )
 {
     Abc_Ntk_t * pNtk = Abc_FrameReadNtk(pAbc);
-    int nMaxSize;
     int ElimValue;
+    int nMaxSize;
+    int nIterMax;
     int fGreedy;
     int fReverse;
     int fVerbose;
     int c;
     extern int Abc_NtkEliminate( Abc_Ntk_t * pNtk, int nMaxSize, int fReverse, int fVerbose );
-    extern int Abc_NtkEliminate1( Abc_Ntk_t * pNtk, int ElimValue, int nMaxSize, int fReverse, int fVerbose );
+    extern int Abc_NtkEliminate1( Abc_Ntk_t * pNtk, int ElimValue, int nMaxSize, int nIterMax, int fReverse, int fVerbose );
 
     // set the defaults
-    nMaxSize  = 30;
     ElimValue = -1;
+    nMaxSize  = 12;
+    nIterMax  =  1;
     fGreedy   =  0;
     fReverse  =  0;
     fVerbose  =  0;
     Extra_UtilGetoptReset();
-    while ( (c = Extra_UtilGetopt(argc, argv, "VNgrvh")) != EOF )
+    while ( (c = Extra_UtilGetopt(argc, argv, "VNIgrvh")) != EOF )
     {
         switch (c)
         {
@@ -3788,6 +3790,17 @@ int Abc_CommandEliminate( Abc_Frame_t * pAbc, int argc, char ** argv )
                 if ( nMaxSize <= 0 )
                     goto usage;
                 break;
+            case 'I':
+                if ( globalUtilOptind >= argc )
+                {
+                    Abc_Print( -1, "Command line switch \"-I\" should be followed by a positive integer.\n" );
+                    goto usage;
+                }
+                nIterMax = atoi(argv[globalUtilOptind]);
+                globalUtilOptind++;
+                if ( nIterMax <= 0 )
+                    goto usage;
+                break;
             case 'g':
                 fGreedy ^= 1;
                 break;
@@ -3826,15 +3839,16 @@ int Abc_CommandEliminate( Abc_Frame_t * pAbc, int argc, char ** argv )
     if ( fGreedy )
         Abc_NtkEliminate( pNtk, nMaxSize, fReverse, fVerbose );
     else
-        Abc_NtkEliminate1( pNtk, ElimValue, nMaxSize, fReverse, fVerbose );
+        Abc_NtkEliminate1( pNtk, ElimValue, nMaxSize, nIterMax, fReverse, fVerbose );
     return 0;
 
 usage:
-    Abc_Print( -2, "usage: eliminate [-VN <num>] [-grvh]\n");
+    Abc_Print( -2, "usage: eliminate [-VNI <num>] [-grvh]\n");
     Abc_Print( -2, "\t           traditional \"eliminate -1\", which collapses the node into its fanout\n");
     Abc_Print( -2, "\t           if the node's variable appears in the fanout's factored form only once\n");
     Abc_Print( -2, "\t-V <num> : the \"value\" parameter used by \"eliminate\" in SIS [default = %d]\n", ElimValue );
     Abc_Print( -2, "\t-N <num> : the maximum node support after collapsing [default = %d]\n", nMaxSize );
+    Abc_Print( -2, "\t-I <num> : the maximum number of iterations [default = %d]\n", nIterMax );
     Abc_Print( -2, "\t-g       : toggle using greedy eliminate (without \"value\") [default = %s]\n", fGreedy? "yes": "no" );
     Abc_Print( -2, "\t-r       : use the reverse topological order [default = %s]\n", fReverse? "yes": "no" );
     Abc_Print( -2, "\t-v       : print verbose information [default = %s]\n", fVerbose? "yes": "no" );