2 * Simple random number generator for testing.
3 * Copyright © 2022-2023 Nick Bowler
5 * Directly compare the test lib RNG against the reference implementation.
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <https://www.gnu.org/licenses/>.
27 tap_skip_all("cannot compile reference xoshiro256+");
35 unsigned long long seed_state = 0xdeadbeeff00dcafe;
36 unsigned long long test_result, ref_result;
37 unsigned long long ref_state[4], test_state[4];
41 for (i = 0; i < 100; i++) {
42 s[0] = ref_state[0] = test_state[0] = splitmix64(&seed_state);
43 s[1] = ref_state[1] = test_state[1] = splitmix64(&seed_state);
44 s[2] = ref_state[2] = test_state[2] = splitmix64(&seed_state);
45 s[3] = ref_state[3] = test_state[3] = splitmix64(&seed_state);
48 test_result = xoshiro256p(test_state);
50 if (!tap_result(ref_result == test_result, "rng output")) {
51 tap_diag("Failed, unexpected result");
52 tap_diag(" with initial state %llx %llx %llx %llx",
53 ref_state[0], ref_state[1],
54 ref_state[2], ref_state[3]);
55 tap_diag(" received: %llx", test_result);
56 tap_diag(" expected: %llx", ref_result);
59 if (!tap_result(s[0] == test_state[0] && s[1] == test_state[1]
60 && s[2] == test_state[2] && s[3] == test_state[3],
63 tap_diag("Failed, state update differed");
64 tap_diag(" with initial state %llx %llx %llx %llx",
65 ref_state[0], ref_state[1],
66 ref_state[2], ref_state[3]);
67 tap_diag(" received: %llx %llx %llx %llx",
68 test_state[0], test_state[1],
69 test_state[2], test_state[3]);
70 tap_diag(" expected: %llx %llx %llx %llx",
71 (unsigned long long)s[0],
72 (unsigned long long)s[1],
73 (unsigned long long)s[2],
74 (unsigned long long)s[3]);