There are various points where you can see if your device will not be supported even if your router isn't listed here!
A router can not be supported by dd-wrt if:
it is based on a Texas Instruments (TI) chipset
it is based on a Marvell chipset not currently supported (Linksys WRT AC Series)
it is based on a Ubicom chipset
it is based on a Realtek chipset
it is based on a Broadcom 63xx chipset
it is based on a Trendchip chipset
it has <2MB flash
it has <4MB flash and is NOT Broadcom (any other supported vendor) based
it has <16MB RAM and is NOT Broadcom (any other supported vendor) based
it has an integrated modem (dd-wrt is router firmware and does not support the modem part)