/**
* @file SFMT.c
* @brief SIMD oriented Fast Mersenne Twister(SFMT)
*
* @author Mutsuo Saito (Hiroshima University)
* @author Makoto Matsumoto (Hiroshima University)
*
* Copyright (C) 2006, 2007 Mutsuo Saito, Makoto Matsumoto and Hiroshima
* University.
* Copyright (C) 2012 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
*/
#if defined(__cplusplus)
extern "C" {
#endif
#include <string.h>
#include <assert.h>
#include "SFMT.h"
#include "SFMT-params.h"
#include "SFMT-common.h"
#if defined(__BIG_ENDIAN__) && !defined(__amd64) && !defined(BIG_ENDIAN64)
#define BIG_ENDIAN64 1
#endif
#if defined(HAVE_ALTIVEC) && !defined(BIG_ENDIAN64)
#define BIG_ENDIAN64 1
#endif
#if defined(ONLY64) && !defined(BIG_ENDIAN64)
#if defined(__GNUC__)
#error "-DONLY64 must be specified with -DBIG_ENDIAN64"
#endif
#undef ONLY64
#endif
/**
* parameters used by sse2.
*/
static const w128_t sse2_param_mask = {{SFMT_MSK1, SFMT_MSK2,
SFMT_MSK3, SFMT_MSK4}};
/*----------------
STATIC FUNCTIONS
----------------*/
inline static int idxof(int i);
inline static void gen_rand_array(sfmt_t * sfmt, w128_t *array, int size);
inline static uint32_t func1(uint32_t x);
inline static uint32_t func2(uint32_t x);
static void period_certification(sfmt_t * sfmt);
#if defined(BIG_ENDIAN64) && !defined(ONLY64)
inline static void swap(w128_t *array, int size);
#endif
#if defined(HAVE_ALTIVEC)
#include "SFMT-alti.h"
#elif defined(HAVE_SSE2)
#include "SFMT-sse2.h"
#endif
/**
* This function simulate a 64-bit index of LITTLE ENDIAN
* in BIG ENDIAN machine.
*/
#ifdef ONLY64
inline static int idxof(int i) {
return i ^ 1;
}
#else
inline static int idxof(int i) {
return i;
}
#endif
#if (!defined(HAVE_ALTIVEC)) && (!defined(HAVE_SSE2))
/**
* This function fills the user-specified array with pseudorandom
* integers.
*
* @param sfmt SFMT internal state
* @param array an 128-bit array to be filled by pseudorandom numbers.
* @param size number of 128-bit pseudorandom numbers to be generated.
*/
inline static void gen_rand_array(sfmt_t * sfmt, w128_t *array, int size) {
int i, j;
w128_t *r1, *r2;
r1 = &sfmt->state[SFMT_N - 2];
r2 = &sfmt->state[SFMT_N - 1];
for (i = 0; i < SFMT_N - SFMT_POS1; i++) {
do_recursion(&array[i], &sfmt->state[i], &sfmt->state[i + SFMT_POS1], r1, r2);
r1 = r2;
r2 = &array[i];
}
for (; i < SFMT_N; i++) {
do_recursion(&array[i], &sfmt->state[i],
&array[i + SFMT_POS1 - SFMT_N], r1, r2);
r1 = r2;
r2 = &array[i];
}
for (; i < size - SFMT_N; i++) {
do_recursion(&array[i], &array[i - SFMT_N],
&array[i + SFMT_POS1 - SFMT_N], r1, r2);
r1 = r2;
r2 = &array[i];
}
for (j = 0; j < 2 * SFMT_N - size; j++) {
sfmt->state[j] = array[j + size - SFMT_N];
}
for (; i < size; i++, j++) {
do_recursion(&array[i], &array[i - SFMT_N],
&array[i + SFMT_POS1 - SFMT_N], r1, r2);
r1 = r2;
r2 = &array[i];
sfmt->state[j] = array[i];
}
}
#endif
#if defined(BIG_ENDIAN64) && !defined(ONLY64) && !defined(HAVE_ALTIVEC)
inline static void swap(w128_t *array, int size) {
int i;
uint32_t x, y;
for (i = 0; i < size; i++) {
x = array[i].u[0];
y = array[i].u[2];
array[i].u[0] = array[i].u[1];
array[i].u[2] = array[i].u[3];
array[i].u[1] = x;
array[i].u[3] = y;
}
}
#endif
/**
* This function represents a function used in the initialization
* by init_by_array
* @param x 32-bit integer
* @return 32-bit integer
*/
static uint32_t func1(uint32_t x) {
return (x ^ (x >> 27)) * (uint32_t)1664525UL;
}
/**
* This function represents a function used in the initialization
* by init_by_array
* @param x 32-bit integer
* @return 32-bit integer
*/
static uint32_t func2(uint32_t x) {
return (x ^ (x >> 27)) * (uint32_t)1566083941UL;
}
/**
* This function certificate the period of 2^{MEXP}
* @param sfmt SFMT internal state
*/
static void period_certification(sfmt_t * sfmt) {
int inner = 0;
int i, j;
uint32_t work;
uint32_t *psfmt32 = &sfmt->state[0].u[0];
const uint32_t parity[4] = {SFMT_PARITY1, SFMT_PARITY2,
SFMT_PARITY3, SFMT_PARITY4};
for (i = 0; i < 4; i++)
inner ^= psfmt32[idxof(i)] & parity[i];
for (i = 16; i > 0; i >>= 1)
inner ^= inner >> i;
inner &= 1;
/* check OK */
if (inner == 1) {
return;
}
/* check NG, and modification */
for (i = 0; i < 4; i++) {
work = 1;
for (j = 0; j < 32; j++) {
if ((work & parity[i]) != 0) {
psfmt32[idxof(i)] ^= work;
return;
}
work = work << 1;
}
}
}
/*----------------
PUBLIC FUNCTIONS
----------------*/
#define UNUSED_VARIABLE(x) (void)(x)
/**
* This function returns the identification string.
* The string shows the word size, the Mersenne exponent,
* and all parameters of this generator.
* @param sfmt SFMT internal state
*/
const char *sfmt_get_idstring(sfmt_t * sfmt) {
UNUSED_VARIABLE(sfmt);
return SFMT_IDSTR;
}
/**
* This function returns the minimum size of array used for \b
* fill_array32() function.
* @param sfmt SFMT internal state
* @return minimum size of array used for fill_array32() function.
*/
int sfmt_get_min_array_size32(sfmt_t * sfmt) {
UNUSED_VARIABLE(sfmt);
return SFMT_N32;
}
/**
* This function returns the minimum size of array used for \b
* fill_array64() function.
* @param sfmt SFMT internal state
* @return minimum size of array used for fill_array64() function.
*/
int sfmt_get_min_array_size64(sfmt_t * sfmt) {
UNUSED_VARIABLE(sfmt);
return SFMT_N64;
}
#if !defined(HAVE_SSE2) && !defined(HAVE_ALTIVEC)
/**
* This function fills the internal state array with pseudorandom
* integers.
* @param sfmt SFMT internal state
*/
void sfmt_gen_rand_all(sfmt_t * sfmt) {
int i;
w128_t *r1, *r2;
r1 = &sfmt->state[SFMT_N - 2];
r2 = &sfmt->state[SFMT_N - 1];
for (i = 0; i < SFMT_N - SFMT_POS1; i++) {
do_recursion(&sfmt->state[i], &sfmt->state[i],
&sfmt->state[i + SFMT_POS1], r1, r2);
r1 = r2;
r2 = &sfmt->state[i];
}
for (; i < SFMT_N; i++) {
do_recursion(&sfmt->state[i], &sfmt->state[i],
&sfmt->state[i + SFMT_POS1 - SFMT_N], r1, r2);
r1 = r2;
r2 = &sfmt->state[i];
}
}
#endif
#ifndef ONLY64
/**
* This function generates pseudorandom 32-bit integers in the
* specified array[] by one call. The number of pseudorandom integers
* is specified by the argument size, which must be at least 624 and a
* multiple of four. The generation by this function is much faster
* than the following gen_rand function.
*
* For initialization, init_gen_rand or init_by_array must be called
* before the first call of this function. This function can not be
* used after calling gen_rand function, without initialization.
*
* @param sfmt SFMT internal state
* @param array an array where pseudorandom 32-bit integers are filled
* by this function. The pointer to the array must be \b "aligned"
* (namely, must be a multiple of 16) in the SIMD version, since it
* refers to the address of a 128-bit integer. In the standard C
* version, the pointer is arbitrary.
*
* @param size the number of 32-bit pseudorandom integers to be
* generated. size must be a multiple of 4, and greater than or equal
* to (MEXP / 128 + 1) * 4.
*
* @note \b memalign or \b posix_memalign is available to get aligned
* memory. Mac OSX doesn't have these functions, but \b malloc of OSX
* returns the pointer to the aligned memory block.
*/
void sfmt_fill_array32(sfmt_t * sfmt, uint32_t *array, int size) {
assert(sfmt->idx == SFMT_N32);
assert(size % 4 == 0);
assert(size >= SFMT_N32);
gen_rand_array(sfmt, (w128_t *)array, size / 4);
sfmt->idx = SFMT_N32;
}
#endif
/**
* This function generates pseudorandom 64-bit integers in the
* specified array[] by one call. The number of pseudorandom integers
* is specified by the argument size, which must be at least 312 and a
* multiple of two. The generation by this function is much faster
* than the following gen_rand function.
*
* @param sfmt SFMT internal state
* For initialization, init_gen_rand or init_by_array must be called
* before the first call of this function. This function can not be
* used after calling gen_rand function, without initialization.
*
* @param array an array where pseudorandom 64-bit integers are filled
* by this function. The pointer to the array must be "aligned"
* (namely, must be a multiple of 16) in the SIMD version, since it
* refers to the address of a 128-bit integer. In the standard C
* version, the pointer is arbitrary.
*
* @param size the number of 64-bit pseudorandom integers to be
* generated. size must be a multiple of 2, and greater than or equal
* to (MEXP / 128 + 1) * 2
*
* @note \b memalign or \b posix_memalign is available to get aligned
* memory. Mac OSX doesn't have these functions, but \b malloc of OSX
* returns the pointer to the aligned memory block.
*/
void sfmt_fill_array64(sfmt_t * sfmt, uint64_t *array, int size) {
assert(sfmt->idx == SFMT_N32);
assert(size % 2 == 0);
assert(size >= SFMT_N64);
gen_rand_array(sfmt, (w128_t *)array, size / 2);
sfmt->idx = SFMT_N32;
#if defined(BIG_ENDIAN64) && !defined(ONLY64)
swap((w128_t *)array, size /2);
#endif
}
/**
* This function randomly shuffle the given array
*
* @param sfmt SFMT internal state
* @param array the array that is going to be shuffled
* @param size the size of the array
* @param rsize the size of each record in the array
*/
#include <alloca.h>
void sfmt_genrand_shuffle(sfmt_t * sfmt, void *array, int size, int rsize) {
int i, j;
char *t = (char *)alloca(rsize);
char *ptr = (char *)array;
char *ptri = ptr + (size - 1) * rsize;
for (i = size - 1; i >= 0; i--) {
j = sfmt_genrand_uint32(sfmt) % (i + 1);
if (i != j)
{
char *ptrj = ptr + j * rsize;
memcpy(t, ptri, rsize);
memcpy(ptri, ptrj, rsize);
memcpy(ptrj, t, rsize);
}
ptri -= rsize;
}
}
/**
* This function initializes the internal state array with a 32-bit
* integer seed.
*
* @param sfmt SFMT internal state
* @param seed a 32-bit integer used as the seed.
*/
void sfmt_init_gen_rand(sfmt_t * sfmt, uint32_t seed) {
int i;
uint32_t *psfmt32 = &sfmt->state[0].u[0];
psfmt32[idxof(0)] = seed;
for (i = 1; i < SFMT_N32; i++) {
psfmt32[idxof(i)] = 1812433253UL * (psfmt32[idxof(i - 1)]
^ (psfmt32[idxof(i - 1)] >> 30))
+ i;
}
sfmt->idx = SFMT_N32;
period_certification(sfmt);
}
/**
* This function initializes the internal state array,
* with an array of 32-bit integers used as the seeds
* @param sfmt SFMT internal state
* @param init_key the array of 32-bit integers, used as a seed.
* @param key_length the length of init_key.
*/
void sfmt_init_by_array(sfmt_t * sfmt, uint32_t *init_key, int key_length) {
int i, j, count;
uint32_t r;
int lag;
int mid;
int size = SFMT_N * 4;
uint32_t *psfmt32 = &sfmt->state[0].u[0];
if (size >= 623) {
lag = 11;
} else if (size >= 68) {
lag = 7;
} else if (size >= 39) {
lag = 5;
} else {
lag = 3;
}
mid = (size - lag) / 2;
memset(sfmt, 0x8b, sizeof(sfmt_t));
if (key_length + 1 > SFMT_N32) {
count = key_length + 1;
} else {
count = SFMT_N32;
}
r = func1(psfmt32[idxof(0)] ^ psfmt32[idxof(mid)]
^ psfmt32[idxof(SFMT_N32 - 1)]);
psfmt32[idxof(mid)] += r;
r += key_length;
psfmt32[idxof(mid + lag)] += r;
psfmt32[idxof(0)] = r;
count--;
for (i = 1, j = 0; (j < count) && (j < key_length); j++) {
r = func1(psfmt32[idxof(i)] ^ psfmt32[idxof((i + mid) % SFMT_N32)]
^ psfmt32[idxof((i + SFMT_N32 - 1) % SFMT_N32)]);
psfmt32[idxof((i + mid) % SFMT_N32)] += r;
r += init_key[j] + i;
psfmt32[idxof((i + mid + lag) % SFMT_N32)] += r;
psfmt32[idxof(i)] = r;
i = (i + 1) % SFMT_N32;
}
for (; j < count; j++) {
r = func1(psfmt32[idxof(i)] ^ psfmt32[idxof((i + mid) % SFMT_N32)]
^ psfmt32[idxof((i + SFMT_N32 - 1) % SFMT_N32)]);
psfmt32[idxof((i + mid) % SFMT_N32)] += r;
r += i;
psfmt32[idxof((i + mid + lag) % SFMT_N32)] += r;
psfmt32[idxof(i)] = r;
i = (i + 1) % SFMT_N32;
}
for (j = 0; j < SFMT_N32; j++) {
r = func2(psfmt32[idxof(i)] + psfmt32[idxof((i + mid) % SFMT_N32)]
+ psfmt32[idxof((i + SFMT_N32 - 1) % SFMT_N32)]);
psfmt32[idxof((i + mid) % SFMT_N32)] ^= r;
r -= i;
psfmt32[idxof((i + mid + lag) % SFMT_N32)] ^= r;
psfmt32[idxof(i)] = r;
i = (i + 1) % SFMT_N32;
}
sfmt->idx = SFMT_N32;
period_certification(sfmt);
}
#if defined(__cplusplus)
}
#endif