Improvements to the SAT sweeper (bug fix).

src/proof/cec/cecSatG2.c

@@ -1549,6 +1549,7 @@ int Cec4_ManPerformSweeping( Gia_Man_t * p, Cec_ParFra_t * pPars, Gia_Man_t ** p
         pMan->nAndNodes++;
         pObj->Value = Gia_ManHashAnd( pMan->pNew, Gia_ObjFanin0Copy(pObj), Gia_ObjFanin1Copy(pObj) );
         pObjNew = Gia_ManObj( pMan->pNew, Abc_Lit2Var(pObj->Value) );
+        if ( Gia_ObjIsAnd(pObjNew) )
         if ( Vec_BitEntry(pMan->vFails, Gia_ObjFaninId0(pObjNew, Abc_Lit2Var(pObj->Value))) || 
              Vec_BitEntry(pMan->vFails, Gia_ObjFaninId1(pObjNew, Abc_Lit2Var(pObj->Value))) )
             Vec_BitWriteEntry( pMan->vFails, Abc_Lit2Var(pObjNew->Value), 1 );