fe_copy example

        # e[31] |= 64;         $e[31] = self::intToChr(
            (self::chrToInt($e[31]) & 127) | 64
        );
        # fe_frombytes(x1,p);         $x1 = self::fe_frombytes($p);
        # fe_1(x2);         $x2 = self::fe_1();
        # fe_0(z2);         $z2 = self::fe_0();
        # fe_copy(x3,x1);         $x3 = self::fe_copy($x1);
        # fe_1(z3);         $z3 = self::fe_1();

        # swap = 0;         /** @var int $swap */
        $swap = 0;

        # for (pos = 254;pos >= 0;--pos) {         for ($pos = 254; $pos >= 0; --$pos) {
            # b = e[pos / 8] >> (pos & 7);             /** @var int $b */
            

        # e[31] |= 64;         $e[31] = self::intToChr(
            (self::chrToInt($e[31]) & 127) | 64
        );
        # fe_frombytes(x1,p);         $x1 = self::fe_frombytes($p);
        # fe_1(x2);         $x2 = self::fe_1();
        # fe_0(z2);         $z2 = self::fe_0();
        # fe_copy(x3,x1);         $x3 = self::fe_copy($x1);
        # fe_1(z3);         $z3 = self::fe_1();

        # swap = 0;         /** @var int $swap */
        $swap = 0;

        # for (pos = 254;pos >= 0;--pos) {         for ($pos = 254; $pos >= 0; --$pos) {
            # b = e[pos / 8] >> (pos & 7);             /** @var int $b */
            

$den1 = self::fe_mul($inv_sqrt, $u1); /* den1 = inv_sqrt*u1 */
        $den2 = self::fe_mul($inv_sqrt, $u2); /* den2 = inv_sqrt*u2 */
        $z_inv = self::fe_mul($h->T, self::fe_mul($den1, $den2)); /* z_inv = den1*den2*T */

        $ix = self::fe_mul($h->X, $sqrtm1); /* ix = X*sqrt(-1) */
        $iy = self::fe_mul($h->Y, $sqrtm1); /* iy = Y*sqrt(-1) */
        $eden = self::fe_mul($den1, $invsqrtamd);

        $t_z_inv =  self::fe_mul($h->T, $z_inv); /* t_z_inv = T*z_inv */
        $rotate = self::fe_isnegative($t_z_inv);

        $x_ = self::fe_copy($h->X);
        $y_ = self::fe_copy($h->Y);
        $den_inv = self::fe_copy($den2);

        $x_ = self::fe_cmov($x_, $iy, $rotate);
        $y_ = self::fe_cmov($y_, $ix, $rotate);
        $den_inv = self::fe_cmov($den_inv, $eden, $rotate);

        $x_z_inv = self::fe_mul($x_, $z_inv);
        $y_ = self::fe_cneg($y_, self::fe_isnegative($x_z_inv));


        

ParagonIE_Sodium_Core32_Int32::fromInt(self::$d2[6]),
                    ParagonIE_Sodium_Core32_Int32::fromInt(self::$d2[7]),
                    ParagonIE_Sodium_Core32_Int32::fromInt(self::$d2[8]),
                    ParagonIE_Sodium_Core32_Int32::fromInt(self::$d2[9])
                )
            );
        }
        /** @var ParagonIE_Sodium_Core32_Curve25519_Fe $d2 */
        $r = new ParagonIE_Sodium_Core32_Curve25519_Ge_Cached();
        $r->YplusX = self::fe_add($p->Y, $p->X);
        $r->YminusX = self::fe_sub($p->Y, $p->X);
        $r->Z = self::fe_copy($p->Z);
        $r->T2d = self::fe_mul($p->T, $d2);
        return $r;
    }

    /** * @internal You should not use this directly from another application * * @param ParagonIE_Sodium_Core32_Curve25519_Ge_P3 $p * @return ParagonIE_Sodium_Core32_Curve25519_Ge_P2 */
    public static function ge_p3_to_p2(ParagonIE_Sodium_Core32_Curve25519_Ge_P3 $p)
    {

    public static function ge_p3_to_cached(ParagonIE_Sodium_Core_Curve25519_Ge_P3 $p)
    {
        static $d2 = null;
        if ($d2 === null) {
            $d2 = ParagonIE_Sodium_Core_Curve25519_Fe::fromArray(self::$d2);
        }
        /** @var ParagonIE_Sodium_Core_Curve25519_Fe $d2 */
        $r = new ParagonIE_Sodium_Core_Curve25519_Ge_Cached();
        $r->YplusX = self::fe_add($p->Y, $p->X);
        $r->YminusX = self::fe_sub($p->Y, $p->X);
        $r->Z = self::fe_copy($p->Z);
        $r->T2d = self::fe_mul($p->T, $d2);
        return $r;
    }

    /** * @internal You should not use this directly from another application * * @param ParagonIE_Sodium_Core_Curve25519_Ge_P3 $p * @return ParagonIE_Sodium_Core_Curve25519_Ge_P2 */
    public static function ge_p3_to_p2(ParagonIE_Sodium_Core_Curve25519_Ge_P3 $p)
    {