diff --git a/src/map/if/acd/acdXX.hpp b/src/map/if/acd/acdXX.hpp
index 833e45ba3..cf9bd6a27 100644
--- a/src/map/if/acd/acdXX.hpp
+++ b/src/map/if/acd/acdXX.hpp
@@ -610,7 +610,7 @@ class acdXX_impl
                                             : cost <= 32  ? 4
                                                           : 5;
 
-      if ( ss_vars_needed + free_set_size < 6 )
+      if ( ss_vars_needed + free_set_size < ps.lut_size )
       {
         /* look for a shared variable */
         best_multiplicity = cost;