first public release of wrk

src/tinymt64.c

@@ -0,0 +1,129 @@
+/**
+ * @file tinymt64.c
+ *
+ * @brief 64-bit Tiny Mersenne Twister only 127 bit internal state
+ *
+ * @author Mutsuo Saito (Hiroshima University)
+ * @author Makoto Matsumoto (The University of Tokyo)
+ *
+ * Copyright (C) 2011 Mutsuo Saito, Makoto Matsumoto,
+ * Hiroshima University and The University of Tokyo.
+ * All rights reserved.
+ *
+ * The 3-clause BSD License is applied to this software, see
+ * LICENSE.txt
+ */
+#include "tinymt64.h"
+
+#define MIN_LOOP 8
+
+/**
+ * This function represents a function used in the initialization
+ * by init_by_array
+ * @param[in] x 64-bit integer
+ * @return 64-bit integer
+ */
+static uint64_t ini_func1(uint64_t x) {
+    return (x ^ (x >> 59)) * UINT64_C(2173292883993);
+}
+
+/**
+ * This function represents a function used in the initialization
+ * by init_by_array
+ * @param[in] x 64-bit integer
+ * @return 64-bit integer
+ */
+static uint64_t ini_func2(uint64_t x) {
+    return (x ^ (x >> 59)) * UINT64_C(58885565329898161);
+}
+
+/**
+ * This function certificate the period of 2^127-1.
+ * @param random tinymt state vector.
+ */
+static void period_certification(tinymt64_t * random) {
+    if ((random->status[0] & TINYMT64_MASK) == 0 &&
+	random->status[1] == 0) {
+	random->status[0] = 'T';
+	random->status[1] = 'M';
+    }
+}
+
+/**
+ * This function initializes the internal state array with a 64-bit
+ * unsigned integer seed.
+ * @param random tinymt state vector.
+ * @param seed a 64-bit unsigned integer used as a seed.
+ */
+void tinymt64_init(tinymt64_t * random, uint64_t seed) {
+    random->status[0] = seed ^ ((uint64_t)random->mat1 << 32);
+    random->status[1] = random->mat2 ^ random->tmat;
+    for (int i = 1; i < MIN_LOOP; i++) {
+	random->status[i & 1] ^= i + UINT64_C(6364136223846793005)
+	    * (random->status[(i - 1) & 1]
+	       ^ (random->status[(i - 1) & 1] >> 62));
+    }
+    period_certification(random);
+}
+
+/**
+ * This function initializes the internal state array,
+ * with an array of 64-bit unsigned integers used as seeds
+ * @param random tinymt state vector.
+ * @param init_key the array of 64-bit integers, used as a seed.
+ * @param key_length the length of init_key.
+ */
+void tinymt64_init_by_array(tinymt64_t * random, const uint64_t init_key[],
+			    int key_length) {
+    const int lag = 1;
+    const int mid = 1;
+    const int size = 4;
+    int i, j;
+    int count;
+    uint64_t r;
+    uint64_t st[4];
+
+    st[0] = 0;
+    st[1] = random->mat1;
+    st[2] = random->mat2;
+    st[3] = random->tmat;
+    if (key_length + 1 > MIN_LOOP) {
+	count = key_length + 1;
+    } else {
+	count = MIN_LOOP;
+    }
+    r = ini_func1(st[0] ^ st[mid % size]
+		  ^ st[(size - 1) % size]);
+    st[mid % size] += r;
+    r += key_length;
+    st[(mid + lag) % size] += r;
+    st[0] = r;
+    count--;
+    for (i = 1, j = 0; (j < count) && (j < key_length); j++) {
+	r = ini_func1(st[i] ^ st[(i + mid) % size] ^ st[(i + size - 1) % size]);
+	st[(i + mid) % size] += r;
+	r += init_key[j] + i;
+	st[(i + mid + lag) % size] += r;
+	st[i] = r;
+	i = (i + 1) % size;
+    }
+    for (; j < count; j++) {
+	r = ini_func1(st[i] ^ st[(i + mid) % size] ^ st[(i + size - 1) % size]);
+	st[(i + mid) % size] += r;
+	r += i;
+	st[(i + mid + lag) % size] += r;
+	st[i] = r;
+	i = (i + 1) % size;
+    }
+    for (j = 0; j < size; j++) {
+	r = ini_func2(st[i] + st[(i + mid) % size] + st[(i + size - 1) % size]);
+	st[(i + mid) % size] ^= r;
+	r -= i;
+	st[(i + mid + lag) % size] ^= r;
+	st[i] = r;
+	i = (i + 1) % size;
+    }
+    random->status[0] = st[0] ^ st[1];
+    random->status[1] = st[2] ^ st[3];
+    period_certification(random);
+}