Add "Return and Deallocate" (rtd) instruction.
RTD #d
(SP) -> PC
SP + 4 + d -> SP
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Tested-By: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Message-Id: <20170605100014.22981-1-laurent@vivier.eu>