GitLab

* add implace flip

* add tests
Signed-off-by: lixuanyi <lixuanyi@sensetime.com>

* modify tests
Signed-off-by: lixuanyi <lixuanyi@sensetime.com>

* add inplace tests
Signed-off-by: lixuanyi <lixuanyi@sensetime.com>

* add comments
Signed-off-by: lixuanyi <lixuanyi@sensetime.com>

* fix
Signed-off-by: lixuanyi <lixuanyi@sensetime.com>