Added switch &trim -c to additionally remove direct connections (POs fed by PIs).

src/aig/gia/giaDup.c

@@ -1005,6 +1005,58 @@ Gia_Man_t * Gia_ManDupTrimmed( Gia_Man_t * p, int fTrimCis, int fTrimCos, int fD
 
 /**Function*************************************************************
 
+  Synopsis    [Removes POs driven by PIs and PIs without fanout.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Gia_Man_t * Gia_ManDupTrimmed2( Gia_Man_t * p )
+{
+    Gia_Man_t * pNew;
+    Gia_Obj_t * pObj;
+    int i;
+    // start new manager
+    pNew = Gia_ManStart( Gia_ManObjNum(p) );
+    pNew->pName = Abc_UtilStrsav( p->pName );
+    // check if there are PIs to be added
+    Gia_ManCreateRefs( p );
+    // discount references of POs
+    Gia_ManForEachPo( p, pObj, i )
+        Gia_ObjRefFanin0Dec( p, pObj );
+    // check if PIs are left
+    Gia_ManForEachPi( p, pObj, i )
+        if ( Gia_ObjRefs(p, pObj) )
+            break;
+    if ( i == Gia_ManPiNum(p) ) // there is no PIs - add dummy PI
+        Gia_ManAppendCi(pNew);
+    // add the ROs
+    Gia_ManFillValue( p );
+    Gia_ManConst0(p)->Value = 0;
+    Gia_ManForEachCi( p, pObj, i )
+        if ( Gia_ObjRefs(p, pObj) || Gia_ObjIsRo(p, pObj) )
+            pObj->Value = Gia_ManAppendCi(pNew);
+    Gia_ManForEachAnd( p, pObj, i )
+        pObj->Value = Gia_ManAppendAnd( pNew, Gia_ObjFanin0Copy(pObj), Gia_ObjFanin1Copy(pObj) );
+    // check if there are POs to be added
+    Gia_ManForEachPo( p, pObj, i )
+        if ( !Gia_ObjIsConst0(Gia_ObjFanin0(pObj)) && !Gia_ObjIsPi(p, Gia_ObjFanin0(pObj)) )
+            break;
+    if ( i == Gia_ManPoNum(p) ) // there is no POs - add dummy PO
+        Gia_ManAppendCo( pNew, 0 );
+    Gia_ManForEachCo( p, pObj, i )
+        if ( (!Gia_ObjIsConst0(Gia_ObjFanin0(pObj)) && !Gia_ObjIsPi(p, Gia_ObjFanin0(pObj))) || Gia_ObjIsRi(p, pObj) )
+            Gia_ManAppendCo( pNew, Gia_ObjFanin0Copy(pObj) );
+    Gia_ManSetRegNum( pNew, Gia_ManRegNum(p) );
+    assert( !Gia_ManHasDangling( pNew ) );
+    return pNew;
+}
+
+/**Function*************************************************************
+
   Synopsis    [Duplicates AIG in the DFS order while putting CIs first.]
 
   Description []

src/base/abci/abc.c

@@ -23555,13 +23555,14 @@ usage:
 ***********************************************************************/
 int Abc_CommandAbc9Trim( Abc_Frame_t * pAbc, int argc, char ** argv )
 {
-    Gia_Man_t * pTemp;
+    Gia_Man_t * pTemp, * pTemp2;
     int c;
     int fTrimCis = 1;
     int fTrimCos = 1;
     int fDualOut = 0;
+    int fPoFedByPi = 0;
     Extra_UtilGetoptReset();
-    while ( ( c = Extra_UtilGetopt( argc, argv, "iodh" ) ) != EOF )
+    while ( ( c = Extra_UtilGetopt( argc, argv, "iocdh" ) ) != EOF )
     {
         switch ( c )
         {
@@ -23571,6 +23572,9 @@ int Abc_CommandAbc9Trim( Abc_Frame_t * pAbc, int argc, char ** argv )
         case 'o':
             fTrimCos ^= 1;
             break;
+        case 'c':
+            fPoFedByPi ^= 1;
+            break;
         case 'd':
             fDualOut ^= 1;
             break;
@@ -23586,14 +23590,21 @@ int Abc_CommandAbc9Trim( Abc_Frame_t * pAbc, int argc, char ** argv )
         return 1;
     } 
     pTemp = Gia_ManDupTrimmed( pAbc->pGia, fTrimCis, fTrimCos, fDualOut );
+    if ( fPoFedByPi )
+    {
+        extern Gia_Man_t * Gia_ManDupTrimmed2( Gia_Man_t * p );
+        pTemp = Gia_ManDupTrimmed2( pTemp2 = pTemp );
+        Gia_ManStop( pTemp2 );
+    }
     Abc_CommandUpdate9( pAbc, pTemp );
     return 0;
 
 usage:
-    Abc_Print( -2, "usage: &trim [-iodh]\n" );
+    Abc_Print( -2, "usage: &trim [-iocdh]\n" );
     Abc_Print( -2, "\t         removes PIs without fanout and PO driven by constants\n" );
     Abc_Print( -2, "\t-i     : toggle removing PIs [default = %s]\n", fTrimCis? "yes": "no" );
     Abc_Print( -2, "\t-o     : toggle removing POs [default = %s]\n", fTrimCos? "yes": "no" );
+    Abc_Print( -2, "\t-c     : toggle additionally removing POs fed by PIs [default = %s]\n", fPoFedByPi? "yes": "no" );
     Abc_Print( -2, "\t-d     : toggle using dual-output miter [default = %s]\n", fDualOut? "yes": "no" );
     Abc_Print( -2, "\t-h     : print the command usage\n");
     return 1;