protected function sphUnpackU64($v)
    {
        list($hi, $lo) = array_values(unpack('N*N*', $v));

        if (PHP_INT_SIZE >= 8) {
            if ($hi < 0) {
                $hi += (1 << 32);
            } // because php 5.2.2 to 5.2.5 is totally fucked up again
            if ($lo < 0) {
                $lo += (1 << 32);
            }

            // x64, int
            if ($hi <= 2147483647) {
                return ($hi << 32) + $lo;
            }

            // x64, bcmath
            if (function_exists('bcmul')) {
                return bcadd($lo, bcmul($hi, '4294967296'));
            }

            // x64, no-bcmath
            $C = 100000;
            $h = ((int) ($hi / $C) << 32) + (int) ($lo / $C);
            $l = (($hi % $C) << 32) + ($lo % $C);
            if ($l > $C) {
                $h += (int) ($l / $C);
                $l = $l % $C;
            }

            if ($h == 0) {
                return $l;
            }

            return sprintf('%d%05d', $h, $l);
        }

        // x32, int
        if ($hi == 0) {
            if ($lo > 0) {
                return $lo;
            }

            return sprintf('%u', $lo);
        }

        $hi = sprintf('%u', $hi);
        $lo = sprintf('%u', $lo);

        // x32, bcmath
        if (function_exists('bcmul')) {
            return bcadd($lo, bcmul($hi, '4294967296'));
        }

        // x32, no-bcmath
        $hi = (float) $hi;
        $lo = (float) $lo;

        $q = floor($hi / 10000000.0);
        $r = $hi - $q * 10000000.0;
        $m = $lo + $r * 4967296.0;
        $mq = floor($m / 10000000.0);
        $l = $m - $mq * 10000000.0;
        $h = $q * 4294967296.0 + $r * 429.0 + $mq;

        $h = sprintf('%.0f', $h);
        $l = sprintf('%07.0f', $l);
        if ($h == '0') {
            return sprintf('%.0f', (float) $l);
        }

        return $h.$l;
    }