add various optimizations

sim/port.lua

@@ -1,4 +1,6 @@
 
+local ffi = FFI
+
 PortTypes = {
 	output = 0,
 	input = 1,
@@ -17,13 +19,15 @@ Port = {}
 
 function Port.new(type, direction, position, causeupdate, idx)
 	local o = {
+		--state = ffi.new("long long", 0),
+		state = 0,
+		group = nil,
+		
 		type = type,
 		direction = direction,
 		position = position,
 		causeupdate = causeupdate,
-		state = 0,
 		gate = nil,
-		group = nil,
 		idx = idx,
 	}
 	return o