func (v *Element) Equal(u *Element) int { sa, sv := u.Bytes(), v.Bytes() return subtle.ConstantTimeCompare(sa, sv) } // mask64Bits returns 0xffffffff if cond is 1, and 0 otherwise. func mask64Bits(cond int) uint64 { return ^(uint64(cond) - 1) } // Select sets v to a if cond == 1, and to b if cond == 0. func (v *Element) Select(a, b *Element, cond int) *Element { m := mask64Bits(cond) v.l0 = (m & a.l0) | (^m & b.l0) v.l1 = (m & a.l1) | (^m & b.l1) v.l2 = (m & a.l2) | (^m & b.l2) v.l3 = (m & a.l3)...