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 r22926978 = x;
        double r22926979 = 1.0;
        double r22926980 = r22926978 + r22926979;
        double r22926981 = sqrt(r22926980);
        double r22926982 = sqrt(r22926978);
        double r22926983 = r22926981 - r22926982;
        double r22926984 = y;
        double r22926985 = r22926984 + r22926979;
        double r22926986 = sqrt(r22926985);
        double r22926987 = sqrt(r22926984);
        double r22926988 = r22926986 - r22926987;
        double r22926989 = r22926983 + r22926988;
        double r22926990 = z;
        double r22926991 = r22926990 + r22926979;
        double r22926992 = sqrt(r22926991);
        double r22926993 = sqrt(r22926990);
        double r22926994 = r22926992 - r22926993;
        double r22926995 = r22926989 + r22926994;
        double r22926996 = t;
        double r22926997 = r22926996 + r22926979;
        double r22926998 = sqrt(r22926997);
        double r22926999 = sqrt(r22926996);
        double r22927000 = r22926998 - r22926999;
        double r22927001 = r22926995 + r22927000;
        return r22927001;
}