+void set_opt_unreachable_code(int value);
+int get_opt_unreachable_code(void);
+
+/* Performs Straightening, if simplifications and loop simplifications. */
+void set_opt_control_flow(int value);
+int get_opt_control_flow(void);
+
+/* If opt_reassociation == 1 reassociation is performed.
+ Default: opt_reassociation == 1. */
+void set_opt_reassociation(int value);
+int get_opt_reassociation(void);