Remove is_swept_object

The name is misleading, as it seems like the function checks whether the
object is swept or not. But the function only checks whether the page is
before or after sweeping.

gc.c

@@ -4372,19 +4372,12 @@ rb_objspace_call_finalizer(rb_objspace_t *objspace)
     ATOMIC_SET(finalizing, 0);
 }
 
-static inline int
-is_swept_object(VALUE ptr)
-{
-    struct heap_page *page = GET_HEAP_PAGE(ptr);
-    return page->flags.before_sweep ? FALSE : TRUE;
-}
-
 /* garbage objects will be collected soon. */
 static inline int
 is_garbage_object(rb_objspace_t *objspace, VALUE ptr)
 {
     if (!is_lazy_sweeping(objspace) ||
-        is_swept_object(ptr) ||
+        !GET_HEAP_PAGE(ptr)->flags.before_sweep ||
         MARKED_IN_BITMAP(GET_HEAP_MARK_BITS(ptr), ptr)) {
 
         return FALSE;
@@ -13570,7 +13563,7 @@ rb_gcdebug_print_obj_condition(VALUE obj)
 
     if (is_lazy_sweeping(objspace)) {
         fprintf(stderr, "lazy sweeping?: true\n");
-        fprintf(stderr, "swept?: %s\n", is_swept_object(obj) ? "done" : "not yet");
+        fprintf(stderr, "page swept?: %s\n", GET_HEAP_PAGE(ptr)->flags.before_sweep ? "false" : "true");
     }
     else {
         fprintf(stderr, "lazy sweeping?: false\n");