selIsZero := subtle.ConstantTimeByteEq(sel, 0) p.Select(NewP256Point(), t.Projective(), selIsZero) for index >= 5 { index -= 6 if index >= 0 { sel, sign = boothW6(s.Rsh(index) & 0b1111111) } else { // Booth encoding considers a virtual zero bit at index -1, // so we shift left the least significant limb. wvalue := (s[0] << 1) & 0b1111111 sel, sign = boothW6(wvalue) } table := &p256GeneratorTables[(index+1)/6] table.Select(t, sel) t.Negate(sign) selIsZero := subtle.ConstantTimeByteEq(sel, 0) p.AddAffine(p,...