status-im/status-go

package alias

// For details: https://en.wikipedia.org/wiki/Linear-feedback_shift_register
type LSFR struct {
    data uint64
    poly uint64
}

func newLSFR(poly uint64, seed uint64) *LSFR {
    return &LSFR{data: seed, poly: poly}
}

func (f *LSFR) next() uint64 {
    var bit uint64
    var i uint64

    for i = 0; i < 64; i++ {
        if f.poly&(1<<i) != 0 {
            bit ^= (f.data >> i)
        }
    }
    bit &= 0x01

    f.data = (f.data << 1) | bit

    return f.data
}