Small improvements for debug messaging

Author: malloch

src/expression/expr_evaluator.h

@@ -190,6 +190,9 @@ int mpr_expr_eval(mpr_expr expr, ebuffer buff, mpr_value *v_in, mpr_value *v_var
 
         switch (tok->toktype & TOKEN_MASK) {
         case TOK_COND_EVAL: {
+#if TRACE_EVAL
+            printf("\n");
+#endif
             if (v_in && v_out) {
                 /* calculate bitflags for updated sources */
                 // TODO: skip this calculation for subsequent conditional evaluation tokens

src/signal.c

@@ -301,8 +301,10 @@ static void process_maps(mpr_local_sig sig, int id_map_idx)
         /* copy input value */
         mpr_slot_set_value(src_slot, inst_idx, mpr_value_get_value(sig->value, inst_idx, 0), time);
 
-        if (!mpr_slot_get_causes_update((mpr_slot)src_slot))
+        if (!mpr_slot_get_causes_update((mpr_slot)src_slot)) {
+            trace("slot update does not cause expression evaluation\n");
             continue;
+        }
 
         if (all) {
             /* find a source signal with more instances */