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7371c4a516
cryptographically secure random number generator, if available, instead of the current time. - Changed the random number generator from Lee Killough's algorithm to the SFMT607 variant of the Mersenne Twister. SVN r1507 (trunk)
156 lines
4.1 KiB
C
156 lines
4.1 KiB
C
/**
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* @file SFMT-alti.h
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*
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* @brief SIMD oriented Fast Mersenne Twister(SFMT)
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* pseudorandom number generator
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*
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* @author Mutsuo Saito (Hiroshima University)
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* @author Makoto Matsumoto (Hiroshima University)
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*
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* Copyright (C) 2007 Mutsuo Saito, Makoto Matsumoto and Hiroshima
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* University. All rights reserved.
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*
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* The new BSD License is applied to this software.
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* see LICENSE.txt
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*/
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#ifndef SFMT_ALTI_H
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#define SFMT_ALTI_H
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inline static vector unsigned int vec_recursion(vector unsigned int a,
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vector unsigned int b,
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vector unsigned int c,
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vector unsigned int d)
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ALWAYSINLINE;
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/**
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* This function represents the recursion formula in AltiVec and BIG ENDIAN.
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* @param a a 128-bit part of the interal state array
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* @param b a 128-bit part of the interal state array
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* @param c a 128-bit part of the interal state array
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* @param d a 128-bit part of the interal state array
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* @return output
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*/
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inline static vector unsigned int vec_recursion(vector unsigned int a,
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vector unsigned int b,
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vector unsigned int c,
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vector unsigned int d) {
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const vector unsigned int sl1 = ALTI_SL1;
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const vector unsigned int sr1 = ALTI_SR1;
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#ifdef ONLY64
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const vector unsigned int mask = ALTI_MSK64;
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const vector unsigned char perm_sl = ALTI_SL2_PERM64;
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const vector unsigned char perm_sr = ALTI_SR2_PERM64;
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#else
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const vector unsigned int mask = ALTI_MSK;
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const vector unsigned char perm_sl = ALTI_SL2_PERM;
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const vector unsigned char perm_sr = ALTI_SR2_PERM;
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#endif
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vector unsigned int v, w, x, y, z;
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x = vec_perm(a, (vector unsigned int)perm_sl, perm_sl);
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v = a;
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y = vec_sr(b, sr1);
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z = vec_perm(c, (vector unsigned int)perm_sr, perm_sr);
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w = vec_sl(d, sl1);
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z = vec_xor(z, w);
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y = vec_and(y, mask);
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v = vec_xor(v, x);
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z = vec_xor(z, y);
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z = vec_xor(z, v);
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return z;
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}
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/**
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* This function fills the internal state array with pseudorandom
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* integers.
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*/
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inline static void gen_rand_all(void) {
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int i;
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vector unsigned int r, r1, r2;
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r1 = sfmt[N - 2].s;
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r2 = sfmt[N - 1].s;
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for (i = 0; i < N - POS1; i++) {
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r = vec_recursion(sfmt[i].s, sfmt[i + POS1].s, r1, r2);
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sfmt[i].s = r;
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r1 = r2;
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r2 = r;
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}
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for (; i < N; i++) {
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r = vec_recursion(sfmt[i].s, sfmt[i + POS1 - N].s, r1, r2);
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sfmt[i].s = r;
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r1 = r2;
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r2 = r;
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}
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}
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/**
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* This function fills the user-specified array with pseudorandom
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* integers.
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*
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* @param array an 128-bit array to be filled by pseudorandom numbers.
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* @param size number of 128-bit pesudorandom numbers to be generated.
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*/
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inline static void gen_rand_array(w128_t *array, int size) {
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int i, j;
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vector unsigned int r, r1, r2;
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r1 = sfmt[N - 2].s;
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r2 = sfmt[N - 1].s;
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for (i = 0; i < N - POS1; i++) {
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r = vec_recursion(sfmt[i].s, sfmt[i + POS1].s, r1, r2);
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array[i].s = r;
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r1 = r2;
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r2 = r;
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}
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for (; i < N; i++) {
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r = vec_recursion(sfmt[i].s, array[i + POS1 - N].s, r1, r2);
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array[i].s = r;
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r1 = r2;
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r2 = r;
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}
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/* main loop */
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for (; i < size - N; i++) {
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r = vec_recursion(array[i - N].s, array[i + POS1 - N].s, r1, r2);
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array[i].s = r;
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r1 = r2;
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r2 = r;
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}
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for (j = 0; j < 2 * N - size; j++) {
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sfmt[j].s = array[j + size - N].s;
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}
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for (; i < size; i++) {
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r = vec_recursion(array[i - N].s, array[i + POS1 - N].s, r1, r2);
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array[i].s = r;
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sfmt[j++].s = r;
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r1 = r2;
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r2 = r;
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}
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}
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#ifndef ONLY64
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#if defined(__APPLE__)
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#define ALTI_SWAP (vector unsigned char) \
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(4, 5, 6, 7, 0, 1, 2, 3, 12, 13, 14, 15, 8, 9, 10, 11)
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#else
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#define ALTI_SWAP {4, 5, 6, 7, 0, 1, 2, 3, 12, 13, 14, 15, 8, 9, 10, 11}
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#endif
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/**
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* This function swaps high and low 32-bit of 64-bit integers in user
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* specified array.
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*
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* @param array an 128-bit array to be swaped.
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* @param size size of 128-bit array.
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*/
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inline static void swap(w128_t *array, int size) {
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int i;
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const vector unsigned char perm = ALTI_SWAP;
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for (i = 0; i < size; i++) {
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array[i].s = vec_perm(array[i].s, (vector unsigned int)perm, perm);
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}
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}
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#endif
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#endif
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