Move RCLASS_CLONED to rb_classext_struct

This commit moves RCLASS_CLONED from the flags to the
rb_classext_struct. This frees the FL_USER1 bit.

class.c

@@ -508,8 +508,8 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
     /* cloned flag is refer at constant inline cache
      * see vm_get_const_key_cref() in vm_insnhelper.c
      */
-    FL_SET(clone, RCLASS_CLONED);
-    FL_SET(orig , RCLASS_CLONED);
+    RCLASS_EXT(clone)->cloned = true;
+    RCLASS_EXT(orig)->cloned = true;
 
     if (!FL_TEST(CLASS_OF(clone), FL_SINGLETON)) {
         RBASIC_SET_CLASS(clone, rb_singleton_class_clone(orig));

internal/class.h

@@ -67,7 +67,8 @@ struct rb_classext_struct {
 #endif
     attr_index_t max_iv_count;
     unsigned char variation_count;
-    bool permanent_classpath;
+    bool permanent_classpath : 1;
+    bool cloned : 1;
     VALUE classpath;
 };
 typedef struct rb_classext_struct rb_classext_t;
@@ -110,7 +111,6 @@ STATIC_ASSERT(sizeof_rb_classext_t, sizeof(struct RClass) + sizeof(rb_classext_t
 #define RCLASS_ATTACHED_OBJECT(c) (RCLASS_EXT(c)->as.singleton_class.attached_object)
 
 #define RICLASS_IS_ORIGIN FL_USER0
-#define RCLASS_CLONED     FL_USER1
 #define RCLASS_SUPERCLASSES_INCLUDE_SELF FL_USER2
 #define RICLASS_ORIGIN_SHARED_MTBL FL_USER3
 

vm_insnhelper.c

@@ -895,7 +895,7 @@ vm_get_const_key_cref(const VALUE *ep)
 
     while (cref) {
         if (FL_TEST(CREF_CLASS(cref), FL_SINGLETON) ||
-            FL_TEST(CREF_CLASS(cref), RCLASS_CLONED)) {
+                RCLASS_EXT(CREF_CLASS(cref))->cloned) {
             return key_cref;
         }
         cref = CREF_NEXT(cref);