If we mask off any out-of-band bits before we assign to the
variable, then we don't need to clean it up when reading.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170718200255.31647-5-rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>