Cannot sample enough valid points. (more)

\[\left(\left(\left(\sqrt{x + 1.0} - \sqrt{x}\right) + \left(\sqrt{y + 1.0} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1.0} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1.0} - \sqrt{t}\right)\]
\left(\left(\left(\sqrt{x + 1.0} - \sqrt{x}\right) + \left(\sqrt{y + 1.0} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1.0} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1.0} - \sqrt{t}\right)
double f(double x, double y, double z, double t) {
        double r17194842 = x;
        double r17194843 = 1.0;
        double r17194844 = r17194842 + r17194843;
        double r17194845 = sqrt(r17194844);
        double r17194846 = sqrt(r17194842);
        double r17194847 = r17194845 - r17194846;
        double r17194848 = y;
        double r17194849 = r17194848 + r17194843;
        double r17194850 = sqrt(r17194849);
        double r17194851 = sqrt(r17194848);
        double r17194852 = r17194850 - r17194851;
        double r17194853 = r17194847 + r17194852;
        double r17194854 = z;
        double r17194855 = r17194854 + r17194843;
        double r17194856 = sqrt(r17194855);
        double r17194857 = sqrt(r17194854);
        double r17194858 = r17194856 - r17194857;
        double r17194859 = r17194853 + r17194858;
        double r17194860 = t;
        double r17194861 = r17194860 + r17194843;
        double r17194862 = sqrt(r17194861);
        double r17194863 = sqrt(r17194860);
        double r17194864 = r17194862 - r17194863;
        double r17194865 = r17194859 + r17194864;
        return r17194865;
}