random_dsfmt.h
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#ifndef RANDOM_DSFMT_H
#define RANDOM_DSFMT_H
#include <itpp/base/ittypes.h>
#include <itpp/base/vec.h>
#include <cstring> // required for memset()
#include <ctime>
#include <limits>
#include <itpp/itexports.h>
#if defined(__SSE2__)
# include <emmintrin.h>
#endif
namespace itpp
{
namespace random_details
{
template < int MEXP, int POS1, int SL1, uint64_t MSK1, uint64_t MSK2,
uint64_t FIX1_V, uint64_t FIX2_V, uint64_t PCV1_V, uint64_t PCV2_V >
class ITPP_EXPORT DSFMT
{
public:
//make usefull constants available in typedefed definitions
static const int N = (MEXP - 128) / 104 + 1;
static const uint64_t FIX1 = FIX1_V;
static const uint64_t FIX2 = FIX2_V;
static const uint64_t PCV1 = PCV1_V;
static const uint64_t PCV2 = PCV2_V;
#if defined(__SSE2__)
static const uint32_t MSK32_1 = static_cast< uint32_t >((MSK1 >> 32) & (0xffffffffULL));
static const uint32_t MSK32_2 = static_cast< uint32_t >(MSK1 & (0xffffffffULL));
static const uint32_t MSK32_3 = static_cast< uint32_t >((MSK2 >> 32) & (0xffffffffULL));
static const uint32_t MSK32_4 = static_cast< uint32_t >(MSK2 & (0xffffffffULL));
#endif
struct Context {
union W128_T {
#if defined(__SSE2__)
__m128i si;
__m128d sd;
#endif // __SSE2__
uint64_t u[2];
uint32_t u32[4];
double d[2];
};
typedef union W128_T w128_t;
w128_t status[N + 1];
int idx;
unsigned int last_seed;
};
public:
DSFMT(Context& c): _context(c) {}
void init_gen_rand(unsigned int seed) {
uint32_t *psfmt = &_context.status[0].u32[0];
psfmt[idxof(0)] = seed;
for(int i = 1; i < (N + 1) * 4; i++) {
psfmt[idxof(i)] = 1812433253UL
* (psfmt[idxof(i - 1)] ^ (psfmt[idxof(i - 1)] >> 30)) + i;
}
initial_mask();
period_certification();
_context.idx = Nx2;
_context.last_seed = seed;
}
uint32_t genrand_uint32() {
uint64_t *psfmt64 = &_context.status[0].u[0];
if(_context.idx >= Nx2) {
dsfmt_gen_rand_all();
_context.idx = 0;
}
return (uint32_t)(psfmt64[_context.idx++] & 0xffffffffU);
}
double genrand_close1_open2() {
double *psfmt64 = &_context.status[0].d[0];
if(_context.idx >= Nx2) {
dsfmt_gen_rand_all();
_context.idx = 0;
}
return psfmt64[_context.idx++];
}
double genrand_open_open() {
double *dsfmt64 = &_context.status[0].d[0];
union {
double d;
uint64_t u;
} r;
if(_context.idx >= Nx2) {
dsfmt_gen_rand_all();
_context.idx = 0;
}
r.d = dsfmt64[_context.idx++];
r.u |= 1;
return r.d - 1.0;
}
private:
static const int Nx2 = N * 2;
static const unsigned int SR = 12U;
static const bool bigendian;
#if defined(__SSE2__)
static const __m128i sse2_param_mask;
#endif // __SSE2__
Context& _context;
static int idxof(int i) { return (bigendian ? (i ^ 1) : i); }
void initial_mask() {
const uint64_t LOW_MASK = 0x000fffffffffffffULL;
const uint64_t HIGH_CONST = 0x3ff0000000000000ULL;
uint64_t *psfmt = &_context.status[0].u[0];
for(int i = 0; i < Nx2; i++) {
psfmt[i] = (psfmt[i] & LOW_MASK) | HIGH_CONST;
}
}
void period_certification() {
uint64_t pcv[2] = {PCV1, PCV2};
uint64_t tmp[2];
uint64_t inner;
tmp[0] = (_context.status[N].u[0] ^ FIX1);
tmp[1] = (_context.status[N].u[1] ^ FIX2);
inner = tmp[0] & pcv[0];
inner ^= tmp[1] & pcv[1];
for(int i = 32; i > 0; i >>= 1) {
inner ^= inner >> i;
}
inner &= 1;
/* check OK */
if(inner == 1) {
return;
}
/* check NG, and modification */
#if (PCV2 & 1) == 1
_context.status[N].u[1] ^= 1;
#else
uint64_t work;
for(int i = 1; i >= 0; i--) {
work = 1;
for(int j = 0; j < 64; j++) {
if((work & pcv[i]) != 0) {
_context.status[N].u[i] ^= work;
return;
}
work = work << 1;
}
}
#endif // (PCV2 & 1) == 1
return;
}
static void do_recursion(typename Context::w128_t *r, typename Context::w128_t *a, typename Context::w128_t *b, typename Context::w128_t *lung) {
#if defined(__SSE2__)
const unsigned int SSE2_SHUFF = 0x1bU;
__m128i x = a->si;
__m128i z = _mm_slli_epi64(x, SL1);
__m128i y = _mm_shuffle_epi32(lung->si, SSE2_SHUFF);
z = _mm_xor_si128(z, b->si);
y = _mm_xor_si128(y, z);
__m128i v = _mm_srli_epi64(y, SR);
__m128i w = _mm_and_si128(y, sse2_param_mask);
v = _mm_xor_si128(v, x);
v = _mm_xor_si128(v, w);
r->si = v;
lung->si = y;
#else // standard C++
uint64_t t0 = a->u[0];
uint64_t t1 = a->u[1];
uint64_t L0 = lung->u[0];
uint64_t L1 = lung->u[1];
lung->u[0] = (t0 << SL1) ^ (L1 >> 32) ^ (L1 << 32) ^ b->u[0];
lung->u[1] = (t1 << SL1) ^ (L0 >> 32) ^ (L0 << 32) ^ b->u[1];
r->u[0] = (lung->u[0] >> SR) ^ (lung->u[0] & MSK1) ^ t0;
r->u[1] = (lung->u[1] >> SR) ^ (lung->u[1] & MSK2) ^ t1;
#endif // __SSE2__
}
void dsfmt_gen_rand_all() {
int i;
typename Context::w128_t *status = _context.status;
typename Context::w128_t lung = status[N];
do_recursion(&status[0], &status[0], &status[POS1], &lung);
for(i = 1; i < N - POS1; i++) {
do_recursion(&status[i], &status[i], &status[i + POS1], &lung);
}
for(; i < N; i++) {
do_recursion(&status[i], &status[i], &status[i + POS1 - N], &lung);
}
status[N] = lung;
}
};
// ----------------------------------------------------------------------
// typedefs of different RNG
// ----------------------------------------------------------------------
typedef DSFMT < 521, 3, 25,
0x000fbfefff77efffULL, 0x000ffeebfbdfbfdfULL,
0xcfb393d661638469ULL, 0xc166867883ae2adbULL,
0xccaa588000000000ULL, 0x0000000000000001ULL > DSFMT_521_RNG;
typedef DSFMT < 1279, 9, 19,
0x000efff7ffddffeeULL, 0x000fbffffff77fffULL,
0xb66627623d1a31beULL, 0x04b6c51147b6109bULL,
0x7049f2da382a6aebULL, 0xde4ca84a40000001ULL > DSFMT_1279_RNG;
typedef DSFMT < 2203, 7, 19,
0x000fdffff5edbfffULL, 0x000f77fffffffbfeULL,
0xb14e907a39338485ULL, 0xf98f0735c637ef90ULL,
0x8000000000000000ULL, 0x0000000000000001ULL > DSFMT_2203_RNG;
typedef DSFMT < 4253, 19, 19,
0x0007b7fffef5feffULL, 0x000ffdffeffefbfcULL,
0x80901b5fd7a11c65ULL, 0x5a63ff0e7cb0ba74ULL,
0x1ad277be12000000ULL, 0x0000000000000001ULL > DSFMT_4253_RNG;
typedef DSFMT < 11213, 37, 19,
0x000ffffffdf7fffdULL, 0x000dfffffff6bfffULL,
0xd0ef7b7c75b06793ULL, 0x9c50ff4caae0a641ULL,
0x8234c51207c80000ULL, 0x0000000000000001ULL > DSFMT_11213_RNG;
typedef DSFMT < 19937, 117, 19,
0x000ffafffffffb3fULL, 0x000ffdfffc90fffdULL,
0x90014964b32f4329ULL, 0x3b8d12ac548a7c7aULL,
0x3d84e1ac0dc82880ULL, 0x0000000000000001ULL > DSFMT_19937_RNG;
typedef DSFMT_19937_RNG ActiveDSFMT;
ITPP_EXPORT ActiveDSFMT::Context& lc_get();
ITPP_EXPORT bool lc_is_initialized();
ITPP_EXPORT void lc_mark_initialized();
}
} // namespace itpp
#endif // #ifndef RANDOM_DSFMT_H
itpp::Array
General array class.
Definition array.h:105
itpp::random_details::DSFMT
C++ implementation of dSFMT random number generator.
Definition random_dsfmt.h:99
itpp::random_details::DSFMT::DSFMT
DSFMT(Context &c)
Constructor using a certain context.
Definition random_dsfmt.h:145
itpp::random_details::DSFMT::genrand_close1_open2
double genrand_close1_open2()
Generate uniform [1, 2) double pseudorandom number.
Definition random_dsfmt.h:186
itpp::random_details::DSFMT::init_gen_rand
void init_gen_rand(unsigned int seed)
Initialise the generator with a new seed.
Definition random_dsfmt.h:154
itpp::random_details::DSFMT::genrand_open_open
double genrand_open_open()
Generate uniform (0, 1) double pseudorandom number.
Definition random_dsfmt.h:203
itpp::random_details::DSFMT::genrand_uint32
uint32_t genrand_uint32()
Generate uniform [0, UINT_MAX) integer pseudorandom number.
Definition random_dsfmt.h:168
itpp::sd
ITPP_EXPORT double sd(const vec &In1, const vec &In2)
Spectral distortion between two vectors, in dB.
itpp::random_details::lc_mark_initialized
void lc_mark_initialized()
Function to mark thread-local context as initialized.
Definition random.cpp:57
itpp::random_details::lc_is_initialized
bool lc_is_initialized()
Function to check if thread-local context is initialized.
Definition random.cpp:52
itpp::random_details::ActiveDSFMT
DSFMT_19937_RNG ActiveDSFMT
Active Generator for random (stochastic) sources.
Definition random_dsfmt.h:395
itpp::random_details::lc_get
ActiveDSFMT::Context & lc_get()
Function to access thread-local context for random numbers generation.
Definition random.cpp:47
ittypes.h
IT++ type definitions.
itpp
itpp namespace
Definition itmex.h:37
itpp::FIX1
const Fix_Factory FIX1(1, TC, WRAP)
Fix_Factories for signed Fix/CFix with wrap-around (FIX1, FIX2, ..., FIX64)
itpp::random_details::DSFMT::Context
DSFMT context structure.
Definition random_dsfmt.h:122
itpp::random_details::DSFMT::Context::idx
int idx
State array indexing.
Definition random_dsfmt.h:138
itpp::random_details::DSFMT::Context::last_seed
unsigned int last_seed
Last known seed used to initialize context.
Definition random_dsfmt.h:140
itpp::random_details::DSFMT::Context::W128_T
Data structure to hold 128-bit values.
Definition random_dsfmt.h:124
vec.h
Templated Vector Class Definitions.

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