Commit | Line | Data |
---|---|---|
9613736d SH |
1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | ||
3 | #include <linux/errno.h> | |
4 | ||
5 | #include "test_fpu.h" | |
6 | ||
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 | } |