- /* Random number generators */
- int32_t galois_LFSR; /* Galois LFSR (fast but weak). signed! */
- uint32_t LCG; /* LCG (fast but weak) */
+ /* State of random number generators: */
+
+ /* Galois LFSR (fast but weak) */
+ int32_t galois_LFSR; /* must be signed! */
+
+ /* LCG (fast but weak) */
+ uint32_t LCG;
+
+ /* 64-bit xorshift (fast, moderate strength) */
+ uint32_t xs64_x;
+ uint32_t xs64_y;