// SPDX-License-Identifier: GPL-2.0+

#include <linux/errno.h>

#include "test_fpu.h"

int test_fpu(void)
{
        /*
         * This sequence of operations tests that rounding mode is
         * to nearest and that denormal numbers are supported.
         * Volatile variables are used to avoid compiler optimizing
         * the calculations away.
         */
        volatile double a, b, c, d, e, f, g;

        a = 4.0;
        b = 1e-15;
        c = 1e-310;

        /* Sets precision flag */
        d = a + b;

        /* Result depends on rounding mode */
        e = a + b / 2;

        /* Denormal and very large values */
        f = b / c;

        /* Depends on denormal support */
        g = a + c * f;

        if (d > a && e > a && g > a)
                return 0;
        else
                return -EINVAL;
}