addInt example

self::load_3(self::substr($s, 23, 3)) << 5
        );
        /** @var ParagonIE_Sodium_Core32_Int32 $h8 */
        $h8 = ParagonIE_Sodium_Core32_Int32::fromInt(
            self::load_3(self::substr($s, 26, 3)) << 4
        );
        /** @var ParagonIE_Sodium_Core32_Int32 $h9 */
        $h9 = ParagonIE_Sodium_Core32_Int32::fromInt(
            (self::load_3(self::substr($s, 29, 3)) & 8388607) << 2
        );

        $carry9 = $h9->addInt(1 << 24)->shiftRight(25);
        $h0 = $h0->addInt32($carry9->mulInt(19, 5));
        $h9 = $h9->subInt32($carry9->shiftLeft(25));

        $carry1 = $h1->addInt(1 << 24)->shiftRight(25);
        $h2 = $h2->addInt32($carry1);
        $h1 = $h1->subInt32($carry1->shiftLeft(25));

        $carry3 = $h3->addInt(1 << 24)->shiftRight(25);
        $h4 = $h4->addInt32($carry3);
        $h3 = $h3->subInt32($carry3->shiftLeft(25));

        

        $h4 = $h4->addInt32($c);            # $h4 += $c;         $c = $h4->shiftRight(26);           # $c = $h4 >> 26;         $h4 = $h4->mask(0x3ffffff);         # $h4 &= 0x3ffffff;
        $h0 = $h0->addInt32($c->mulInt(5, 3)); # $h0 += self::mul($c, 5);         $c = $h0->shiftRight(26);           # $c = $h0 >> 26;         $h0 = $h0->mask(0x3ffffff);         # $h0 &= 0x3ffffff;         $h1 = $h1->addInt32($c);            # $h1 += $c;
        /* compute h + -p */
        $g0 = $h0->addInt(5);
        $c  = $g0->shiftRight(26);
        $g0 = $g0->mask(0x3ffffff);
        $g1 = $h1->addInt32($c);
        $c  = $g1->shiftRight(26);
        $g1 = $g1->mask(0x3ffffff);
        $g2 = $h2->addInt32($c);
        $c  = $g2->shiftRight(26);
        $g2 = $g2->mask(0x3ffffff);
        $g3 = $h3->addInt32($c);
        $c  = $g3->shiftRight(26);
        $g3 = $g3->mask(0x3ffffff);
        

$x13 = $x13->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 52, 4)));
            $x14 = $x14->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 56, 4)));
            $x15 = $x15->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 60, 4)));

            /* j12 = PLUSONE(j12); if (!j12) { j13 = PLUSONE(j13); } */
            /** @var ParagonIE_Sodium_Core32_Int32 $j12 */
            $j12 = $j12->addInt(1);
            if ($j12->limbs[0] === 0 && $j12->limbs[1] === 0) {
                $j13 = $j13->addInt(1);
            }

            /* STORE32_LE(c + 0, x0); STORE32_LE(c + 4, x1); STORE32_LE(c + 8, x2); STORE32_LE(c + 12, x3); STORE32_LE(c + 16, x4); STORE32_LE(c + 20, x5); STORE32_LE(c + 24, x6); STORE32_LE(c + 28, x7); STORE32_LE(c + 32, x8); STORE32_LE(c + 36, x9); STORE32_LE(c + 40, x10); STORE32_LE(c + 44, x11); STORE32_LE(c + 48, x12); STORE32_LE(c + 52, x13); STORE32_LE(c + 56, x14); STORE32_LE(c + 60, x15); */

    public static function fe_mul121666(ParagonIE_Sodium_Core32_Curve25519_Fe $f)
    {
        /** @var array<int, ParagonIE_Sodium_Core32_Int64> $h */
        $h = array();
        for ($i = 0; $i < 10; ++$i) {
            $h[$i] = $f[$i]->toInt64()->mulInt(121666, 17);
        }

        $carry9 = $h[9]->addInt(1 << 24)->shiftRight(25);
        $h[0] = $h[0]->addInt64($carry9->mulInt(19, 5));
        $h[9] = $h[9]->subInt64($carry9->shiftLeft(25));

        $carry1 = $h[1]->addInt(1 << 24)->shiftRight(25);
        $h[2] = $h[2]->addInt64($carry1);
        $h[1] = $h[1]->subInt64($carry1->shiftLeft(25));

        $carry3 = $h[3]->addInt(1 << 24)->shiftRight(25);
        $h[4] = $h[4]->addInt64($carry3);
        $h[3] = $h[3]->subInt64($carry3->shiftLeft(25));