Add rb_gc_move_obj_during_marking

Author: peterzhu2118

gc.c

@@ -3173,6 +3173,14 @@ gc_mark_classext_iclass(rb_classext_t *ext, bool prime, VALUE box_value, void *a
 
 #define TYPED_DATA_REFS_OFFSET_LIST(d) (size_t *)(uintptr_t)RTYPEDDATA_TYPE(d)->function.dmark
 
+void
+rb_gc_move_obj_during_marking(VALUE from, VALUE to)
+{
+    if (rb_obj_gen_fields_p(to)) {
+        rb_mark_generic_ivar(from);
+    }
+}
+
 void
 rb_gc_mark_children(void *objspace, VALUE obj)
 {

gc/gc.h

@@ -107,6 +107,7 @@ MODULAR_GC_FN void *rb_gc_get_ractor_newobj_cache(void);
 MODULAR_GC_FN void rb_gc_initialize_vm_context(struct rb_gc_vm_context *context);
 MODULAR_GC_FN void rb_gc_worker_thread_set_vm_context(struct rb_gc_vm_context *context);
 MODULAR_GC_FN void rb_gc_worker_thread_unset_vm_context(struct rb_gc_vm_context *context);
+MODULAR_GC_FN void rb_gc_move_obj_during_marking(VALUE from, VALUE to);
 #endif
 
 #if USE_MODULAR_GC