package Fib (mkFib, mkFib8) where

import FIFO

func :: (Arith a) => Bool -> Reg a -> Reg a -> Reg a
func b x1 x2 = if b then x1 else x2

mkFib8 :: Module (Reg (Bit 8))
mkFib8 = mkFib

mkFib :: (Bits a sa, Arith a) => Module (Reg a)
mkFib =
    module
        x :: Reg a
        x <- mkReg 1

        y :: Reg a
        y <- mkReg 1

        z :: Reg Bool
        z <- mkReg True
        interface
            _write _ = action { x := 1; y := 1; z := True }
            _read = (func z x y)._read
        rules
            when True
              ==> action
                     (func z x y) := x + y;
                     z := not z;