+
+// George Marsaglia's KISS generator
+uint64_t nbd_rand (void) {
+ LOCALIZE_THREAD_LOCAL(rx_, unsigned);
+ LOCALIZE_THREAD_LOCAL(ry_, unsigned);
+ LOCALIZE_THREAD_LOCAL(rz_, unsigned);
+ LOCALIZE_THREAD_LOCAL(rc_, unsigned);
+
+ uint32_t rx = 69069 * rx_ + 12345;
+ uint32_t ry = ry_;
+ uint32_t rz = rz_;
+ ry ^= (ry << 13);
+ ry ^= (ry >> 17);
+ ry ^= (ry << 5);
+ uint64_t t = rz * 698769069LL + rc_;
+ uint64_t r = rx + ry + (rz = t);
+
+ SET_THREAD_LOCAL(rx_, rx);
+ SET_THREAD_LOCAL(ry_, ry);
+ SET_THREAD_LOCAL(rz_, rz);
+ SET_THREAD_LOCAL(rc_, t >> 32);
+
+ return r;
+}
+
+// Fairly fast random numbers
+uint64_t nbd_rand_seed (int i) {
+ return rdtsc() + -715159705 + i * 129;
+}
+
+int nbd_next_rand (uint64_t *r) {
+ *r = (*r * 0x5DEECE66DLL + 0xBLL) & MASK(48);
+ return (*r >> 17) & 0x7FFFFFFF;
+}