Auto-increment on Spider tables with DESC PK does not work properly

--source include/have_innodb.inc

--source include/have_partition.inc

install soname 'ha_spider';

set spider_same_server_link= on;

select @@spider_auto_increment_mode;

eval create server s foreign data wrapper mysql options 

(host '127.0.0.1', database 'test', user 'root', port $MASTER_MYPORT);

create or replace table t (id int primary key) engine=InnoDB;

create or replace table t_sp1 (id int auto_increment, primary key(id desc))

engine=Spider COMMENT='wrapper "mysql", srv "s", table "t"';

create or replace table t_sp2 (id int auto_increment, primary key(id desc))

engine=Spider COMMENT='wrapper "mysql", srv "s", table "t"';

insert into t_sp1 () values (),(),();

insert into t_sp2 () values (),(),();

select * from t_sp2;

 mysqltest: At line 21: query 'insert into t_sp2 () values (),(),()' failed: ER_DUP_ENTRY (1062): Duplicate entry '2' for key 'PRIMARY'

insert into t_sp1 () values (),(),();

insert into t_sp2 () values (),(),();

select * from t_sp2;

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