t/rng-test.c

   1 /*
   2  * Test case for xoshiro256** implementation.
   3  * Copyright © 2022-2024 Nick Bowler
   4  *
   5  * Directly compare the game RNG against the reference implementation.
   6  *
   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.
  11  *
  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.
  16  *
  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/>.
  19  */
  20
  21 #include <config.h>
  22 #include "tap.h"
  23
  24 #if !HAVE_FOR_DECLS
  25 int main(void)
  26 {
  27         tap_skip_all("cannot compile reference xoshiro256**");
  28 }
  29 #else
  30 #include "game-notime.h"
  31 #include "game.c"
  32 #include "xos256ss.c"
  33
  34 int main(void)
  35 {
  36         unsigned long long seed_state = 0xdeadbeeff00dcafe;
  37         unsigned long long test_result, ref_result;
  38         unsigned long long ref_state[4], test_state[4];
  39         int i, ret = 0;
  40
  41         tap_plan(200);
  42         for (i = 0; i < 100; i++) {
  43                 s[0] = ref_state[0] = test_state[0] = splitmix64(&seed_state);
  44                 s[1] = ref_state[1] = test_state[1] = splitmix64(&seed_state);
  45                 s[2] = ref_state[2] = test_state[2] = splitmix64(&seed_state);
  46                 s[3] = ref_state[3] = test_state[3] = splitmix64(&seed_state);
  47
  48                 ref_result = next();
  49                 test_result = xoshiro256ss(test_state);
  50
  51                 if (!tap_result(ref_result == test_result, "rng output")) {
  52                         tap_diag("Failed, unexpected result");
  53                         tap_diag("   with initial state %llx %llx %llx %llx",
  54                                                   ref_state[0], ref_state[1],
  55                                                   ref_state[2], ref_state[3]);
  56                         tap_diag("   received: %llx", test_result);
  57                         tap_diag("   expected: %llx", ref_result);
  58                 }
  59
  60                 if (!tap_result(s[0] == test_state[0] && s[1] == test_state[1]
  61                              && s[2] == test_state[2] && s[3] == test_state[3],
  62                                 "rng state update"))
  63                 {
  64                         tap_diag("Failed, state update differed");
  65                         tap_diag("   with initial state %llx %llx %llx %llx",
  66                                                   ref_state[0], ref_state[1],
  67                                                   ref_state[2], ref_state[3]);
  68                         tap_diag("   received: %llx %llx %llx %llx",
  69                                        test_state[0], test_state[1],
  70                                        test_state[2], test_state[3]);
  71                         tap_diag("   expected: %llx %llx %llx %llx",
  72                                        (unsigned long long)s[0],
  73                                        (unsigned long long)s[1],
  74                                        (unsigned long long)s[2],
  75                                        (unsigned long long)s[3]);
  76                 }
  77         }
  78
  79         tap_done();
  80 }
  81 #endif