1 // SPDX-License-Identifier: GPL-2.0+
2
3 #include <linux/errno.h>
4
5 #include "test_fpu.h"
6
test_fpu(void)7 int test_fpu(void)
8 {
9 /*
10 * This sequence of operations tests that rounding mode is
11 * to nearest and that denormal numbers are supported.
12 * Volatile variables are used to avoid compiler optimizing
13 * the calculations away.
14 */
15 volatile double a, b, c, d, e, f, g;
16
17 a = 4.0;
18 b = 1e-15;
19 c = 1e-310;
20
21 /* Sets precision flag */
22 d = a + b;
23
24 /* Result depends on rounding mode */
25 e = a + b / 2;
26
27 /* Denormal and very large values */
28 f = b / c;
29
30 /* Depends on denormal support */
31 g = a + c * f;
32
33 if (d > a && e > a && g > a)
34 return 0;
35 else
36 return -EINVAL;
37 }
38