| 306 | } |
| 307 | |
| 308 | static Rand64 nextrand (Rand64 *state) { |
| 309 | Rand64 state0 = state[0]; |
| 310 | Rand64 state1 = state[1]; |
| 311 | Rand64 state2 = state[2] ^ state0; |
| 312 | Rand64 state3 = state[3] ^ state1; |
| 313 | Rand64 res = rotl(state1 * 5, 7) * 9; |
| 314 | state[0] = state0 ^ state3; |
| 315 | state[1] = state1 ^ state2; |
| 316 | state[2] = state2 ^ (state1 << 17); |
| 317 | state[3] = rotl(state3, 45); |
| 318 | return res; |
| 319 | } |
| 320 | |
| 321 | |
| 322 | /* must take care to not shift stuff by more than 63 slots */ |