What exactly are you trying to achieve ?
According to the WiKi, RB5009 supports Bridge Vlan Filtering in Hardware Level, meaning that you will not loose the Hardware offload feature…
https://help.mikrotik.com/docs/display/ROS/Switch+Chip+Features
Also, here you can see how Bridge VLAN filtering works :
http://forum.mikrotik.com/t/using-routeros-to-vlan-your-network/126489/1