Add Coccinelle rules - bitmap set operations

Some bitmap set operations recycle one of the input parameters or return
a reference to a new bitmap set. The added set of rules checks that the
returned reference is not discarded.

coccinelle/bms_result.cocci

@@ -0,0 +1,84 @@
+// Some bitmap set operations recycle one of the input parameters or return
+// a reference to a new bitmap set. The following set of rules checks that the
+// returned reference is not discarded.
+
+@rule_1@
+expression E1, E2;
+@@
+
++ /* Result of bms_add_member has to be used */
++ E1 = bms_add_member(E1, E2);
+- bms_add_member(E1, E2);
+
+@rule_2@
+expression E1, E2;
+@@
+
++ /* Result of bms_del_member has to be used */
++ E1 = bms_del_member(E1, E2);
+- bms_del_member(E1, E2);
+
+@rule_3@
+expression E1, E2;
+@@
+
++ /* Result of bms_add_members has to be used */
++ E1 = bms_add_members(E1, E2);
+- bms_add_members(E1, E2);
+
+@rule_4@
+expression E1, E2, E3;
+@@
+
++ /* Result of bms_add_range has to be used */
++ E1 = bms_add_range(E1, E2, E3);
+- bms_add_range(E1, E2, E3);
+
+@rule_5@
+expression E1, E2;
+@@
+
++ /* Result of bms_int_members has to be used */
++ E1 = bms_int_members(E1, E2);
+- bms_int_members(E1, E2);
+
+@rule_6@
+expression E1, E2;
+@@
+
++ /* Result of bms_del_members has to be used */
++ E1 = bms_del_members(E1, E2);
+- bms_del_members(E1, E2);
+
+@rule_7@
+expression E1, E2;
+@@
+
++ /* Result of bms_join has to be used */
++ E1 = bms_join(E1, E2);
+- bms_join(E1, E2);
+
+@rule_8@
+expression E1, E2;
+@@
+
++ /* Result of bms_union has to be used */
++ E1 = bms_union(E1, E2);
+- bms_union(E1, E2);
+
+@rule_9@
+expression E1, E2;
+@@
+
++ /* Result of bms_intersect has to be used */
++ E1 = bms_intersect(E1, E2);
+- bms_intersect(E1, E2);
+
+@rule_10@
+expression E1, E2;
+@@
+
++ /* Result of bms_difference has to be used */
++ E1 = bms_difference(E1, E2);
+- bms_difference(E1, E2);
+