tt_anf.sc

fn bitstripes (n)
    -1:u64 // ((1:u64 << n) | 1)

fn logleveld (x)
    findmsb x

fn tt->anf (x)
    w := (x == 0) 0 (logleveld x)
    S := (logleveld w) + 1
    x := fold (x) for i in (range S)
        w := 1:u64 << i
        M0 := bitstripes w
        M1 := M0 << w
        k := x & M0
        k | ((x & M1) ^ (k << w))
    pass x S

fn anf->tt (x S)
    fold (x) for i in (rrange S)
        w := 1:u64 << i
        M0 := bitstripes w
        M1 := M0 << w
        k := x & M0
        k | ((x & M1) ^ (k << w))

for x in (range 256:u64)
    y S := tt->anf x
    x2 := anf->tt y S
    print
        /nolines
            /bin x
            /anf y
    assert (x == x2)