1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef _LIBCPP___RANDOM_MERSENNE_TWISTER_ENGINE_H
10#define _LIBCPP___RANDOM_MERSENNE_TWISTER_ENGINE_H
11
12#include <__algorithm/equal.h>
13#include <__algorithm/min.h>
14#include <__config>
15#include <__cstddef/size_t.h>
16#include <__random/is_seed_sequence.h>
17#include <__type_traits/enable_if.h>
18#include <cstdint>
19#include <iosfwd>
20#include <limits>
21
22#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
23# pragma GCC system_header
24#endif
25
26_LIBCPP_PUSH_MACROS
27#include <__undef_macros>
28
29_LIBCPP_BEGIN_NAMESPACE_STD
30
31template <class _UIntType,
32 size_t __w,
33 size_t __n,
34 size_t __m,
35 size_t __r,
36 _UIntType __a,
37 size_t __u,
38 _UIntType __d,
39 size_t __s,
40 _UIntType __b,
41 size_t __t,
42 _UIntType __c,
43 size_t __l,
44 _UIntType __f>
45class mersenne_twister_engine;
46
47template <class _UInt,
48 size_t _Wp,
49 size_t _Np,
50 size_t _Mp,
51 size_t _Rp,
52 _UInt _Ap,
53 size_t _Up,
54 _UInt _Dp,
55 size_t _Sp,
56 _UInt _Bp,
57 size_t _Tp,
58 _UInt _Cp,
59 size_t _Lp,
60 _UInt _Fp>
61_LIBCPP_HIDE_FROM_ABI bool
62operator==(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
63 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y);
64
65template <class _CharT,
66 class _Traits,
67 class _UInt,
68 size_t _Wp,
69 size_t _Np,
70 size_t _Mp,
71 size_t _Rp,
72 _UInt _Ap,
73 size_t _Up,
74 _UInt _Dp,
75 size_t _Sp,
76 _UInt _Bp,
77 size_t _Tp,
78 _UInt _Cp,
79 size_t _Lp,
80 _UInt _Fp>
81_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
82operator<<(basic_ostream<_CharT, _Traits>& __os,
83 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
84
85template <class _CharT,
86 class _Traits,
87 class _UInt,
88 size_t _Wp,
89 size_t _Np,
90 size_t _Mp,
91 size_t _Rp,
92 _UInt _Ap,
93 size_t _Up,
94 _UInt _Dp,
95 size_t _Sp,
96 _UInt _Bp,
97 size_t _Tp,
98 _UInt _Cp,
99 size_t _Lp,
100 _UInt _Fp>
101_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
102operator>>(basic_istream<_CharT, _Traits>& __is,
103 mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
104
105template <class _UIntType,
106 size_t __w,
107 size_t __n,
108 size_t __m,
109 size_t __r,
110 _UIntType __a,
111 size_t __u,
112 _UIntType __d,
113 size_t __s,
114 _UIntType __b,
115 size_t __t,
116 _UIntType __c,
117 size_t __l,
118 _UIntType __f>
119class mersenne_twister_engine {
120public:
121 // types
122 typedef _UIntType result_type;
123
124private:
125 result_type __x_[__n];
126 size_t __i_;
127
128 static_assert(0 < __m, "mersenne_twister_engine invalid parameters");
129 static_assert(__m <= __n, "mersenne_twister_engine invalid parameters");
130 static _LIBCPP_CONSTEXPR const result_type _Dt = numeric_limits<result_type>::digits;
131 static_assert(__w <= _Dt, "mersenne_twister_engine invalid parameters");
132 static_assert(2 <= __w, "mersenne_twister_engine invalid parameters");
133 static_assert(__r <= __w, "mersenne_twister_engine invalid parameters");
134 static_assert(__u <= __w, "mersenne_twister_engine invalid parameters");
135 static_assert(__s <= __w, "mersenne_twister_engine invalid parameters");
136 static_assert(__t <= __w, "mersenne_twister_engine invalid parameters");
137 static_assert(__l <= __w, "mersenne_twister_engine invalid parameters");
138
139public:
140 static _LIBCPP_CONSTEXPR const result_type _Min = 0;
141 static _LIBCPP_CONSTEXPR const result_type _Max =
142 __w == _Dt ? result_type(~0) : (result_type(1) << __w) - result_type(1);
143 static_assert(_Min < _Max, "mersenne_twister_engine invalid parameters");
144 static_assert(__a <= _Max, "mersenne_twister_engine invalid parameters");
145 static_assert(__b <= _Max, "mersenne_twister_engine invalid parameters");
146 static_assert(__c <= _Max, "mersenne_twister_engine invalid parameters");
147 static_assert(__d <= _Max, "mersenne_twister_engine invalid parameters");
148 static_assert(__f <= _Max, "mersenne_twister_engine invalid parameters");
149
150 // engine characteristics
151 static inline _LIBCPP_CONSTEXPR const size_t word_size = __w;
152 static inline _LIBCPP_CONSTEXPR const size_t state_size = __n;
153 static inline _LIBCPP_CONSTEXPR const size_t shift_size = __m;
154 static inline _LIBCPP_CONSTEXPR const size_t mask_bits = __r;
155 static inline _LIBCPP_CONSTEXPR const result_type xor_mask = __a;
156 static inline _LIBCPP_CONSTEXPR const size_t tempering_u = __u;
157 static inline _LIBCPP_CONSTEXPR const result_type tempering_d = __d;
158 static inline _LIBCPP_CONSTEXPR const size_t tempering_s = __s;
159 static inline _LIBCPP_CONSTEXPR const result_type tempering_b = __b;
160 static inline _LIBCPP_CONSTEXPR const size_t tempering_t = __t;
161 static inline _LIBCPP_CONSTEXPR const result_type tempering_c = __c;
162 static inline _LIBCPP_CONSTEXPR const size_t tempering_l = __l;
163 static inline _LIBCPP_CONSTEXPR const result_type initialization_multiplier = __f;
164 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
165 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
166 static inline _LIBCPP_CONSTEXPR const result_type default_seed = 5489u;
167
168 // constructors and seeding functions
169#ifndef _LIBCPP_CXX03_LANG
170 _LIBCPP_HIDE_FROM_ABI mersenne_twister_engine() : mersenne_twister_engine(default_seed) {}
171 _LIBCPP_HIDE_FROM_ABI explicit mersenne_twister_engine(result_type __sd) { seed(__sd); }
172#else
173 _LIBCPP_HIDE_FROM_ABI explicit mersenne_twister_engine(result_type __sd = default_seed) { seed(__sd); }
174#endif
175 template <class _Sseq, __enable_if_t<__is_seed_sequence_v<_Sseq, mersenne_twister_engine>, int> = 0>
176 _LIBCPP_HIDE_FROM_ABI explicit mersenne_twister_engine(_Sseq& __q) {
177 seed(__q);
178 }
179 _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd = default_seed) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK {
180 __x_[0] = __sd & _Max;
181 for (size_t __i = 1; __i < __n; ++__i)
182 __x_[__i] = (__f * (__x_[__i - 1] ^ __rshift<__w - 2>(__x_[__i - 1])) + __i) & _Max;
183 __i_ = 0;
184#ifdef _LIBCPP_ABI_VECTORIZED_MERSENNE_TWISTER_ENGINE
185 __update_all_states();
186#endif
187 }
188 template <class _Sseq, __enable_if_t<__is_seed_sequence_v<_Sseq, mersenne_twister_engine>, int> = 0>
189 _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
190 const unsigned __k = 1 + (__w - 1) / 32;
191 static_assert(__k <= 2);
192 uint32_t __ar[__n * __k];
193 __q.generate(__ar, __ar + __n * __k);
194 for (size_t __i = 0; __i < __n; ++__i) {
195 if _LIBCPP_CONSTEXPR (__k == 1) {
196 __x_[__i] = static_cast<result_type>(__ar[__i] & _Max);
197 } else {
198 __x_[__i] = static_cast<result_type>((__ar[2 * __i] + ((uint64_t)__ar[2 * __i + 1] << 32)) & _Max);
199 }
200 }
201 const result_type __mask = __r == _Dt ? result_type(~0) : (result_type(1) << __r) - result_type(1);
202 __i_ = 0;
203 if ((__x_[0] & ~__mask) == 0) {
204 for (size_t __i = 1; __i < __n; ++__i)
205 if (__x_[__i] != 0)
206 return;
207 __x_[0] = result_type(1) << (__w - 1);
208 }
209#ifdef _LIBCPP_ABI_VECTORIZED_MERSENNE_TWISTER_ENGINE
210 __update_all_states();
211#endif
212 }
213
214 void __update_state(size_t __i, size_t __k) {
215 const size_t __j = (__i + 1) % __n;
216 const result_type __mask = __r == _Dt ? result_type(~0) : (result_type(1) << __r) - result_type(1);
217 const result_type __yp = (__x_[__i] & ~__mask) | (__x_[__j] & __mask);
218 __x_[__i] = __x_[__k] ^ __rshift<1>(__yp) ^ (__a * (__yp & 1));
219 }
220
221 void __update_state(size_t __i) { __update_state(__i, (__i + __m) % __n); }
222
223 void __update_all_states() {
224 size_t __i = 0;
225 // This is split into two loops to help the compiler vectorize the code
226 for (; __i != (__n - __m); ++__i)
227 __update_state(__i);
228 for (size_t __j = 0; __i != __n; ++__i, ++__j)
229 __update_state(__i, __j);
230 }
231
232 // generating functions
233 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI result_type operator()() {
234#ifdef _LIBCPP_ABI_VECTORIZED_MERSENNE_TWISTER_ENGINE
235 result_type __val = __x_[__i_];
236 if (++__i_ == __n) [[__unlikely__]] {
237 __update_all_states();
238 __i_ = 0;
239 }
240#else
241 __update_state(__i_);
242 result_type __val = __x_[__i_];
243 __i_ = (__i_ + 1) % __n;
244#endif
245 result_type __z = __val ^ (__rshift<__u>(__val) & __d);
246 __z ^= __lshift<__s>(__z) & __b;
247 __z ^= __lshift<__t>(__z) & __c;
248 return __z ^ __rshift<__l>(__z);
249 }
250
251 _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
252 for (; __z; --__z)
253 (void)operator()();
254 }
255
256 template <class _UInt,
257 size_t _Wp,
258 size_t _Np,
259 size_t _Mp,
260 size_t _Rp,
261 _UInt _Ap,
262 size_t _Up,
263 _UInt _Dp,
264 size_t _Sp,
265 _UInt _Bp,
266 size_t _Tp,
267 _UInt _Cp,
268 size_t _Lp,
269 _UInt _Fp>
270 friend bool operator==(
271 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
272 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y);
273
274 template <class _CharT,
275 class _Traits,
276 class _UInt,
277 size_t _Wp,
278 size_t _Np,
279 size_t _Mp,
280 size_t _Rp,
281 _UInt _Ap,
282 size_t _Up,
283 _UInt _Dp,
284 size_t _Sp,
285 _UInt _Bp,
286 size_t _Tp,
287 _UInt _Cp,
288 size_t _Lp,
289 _UInt _Fp>
290 friend basic_ostream<_CharT, _Traits>& operator<<(
291 basic_ostream<_CharT, _Traits>& __os,
292 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
293
294 template <class _CharT,
295 class _Traits,
296 class _UInt,
297 size_t _Wp,
298 size_t _Np,
299 size_t _Mp,
300 size_t _Rp,
301 _UInt _Ap,
302 size_t _Up,
303 _UInt _Dp,
304 size_t _Sp,
305 _UInt _Bp,
306 size_t _Tp,
307 _UInt _Cp,
308 size_t _Lp,
309 _UInt _Fp>
310 friend basic_istream<_CharT, _Traits>&
311 operator>>(basic_istream<_CharT, _Traits>& __is,
312 mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
313
314private:
315 template <size_t __count>
316 _LIBCPP_HIDE_FROM_ABI static result_type __lshift(result_type __x) {
317 if _LIBCPP_CONSTEXPR (__count < __w) {
318 return (__x << __count) & _Max;
319 } else {
320 return result_type(0);
321 }
322 }
323
324 template <size_t __count>
325 _LIBCPP_HIDE_FROM_ABI static result_type __rshift(result_type __x) {
326 if _LIBCPP_CONSTEXPR (__count < _Dt) {
327 return __x >> __count;
328 } else {
329 return result_type(0);
330 }
331 }
332};
333
334template <class _UInt,
335 size_t _Wp,
336 size_t _Np,
337 size_t _Mp,
338 size_t _Rp,
339 _UInt _Ap,
340 size_t _Up,
341 _UInt _Dp,
342 size_t _Sp,
343 _UInt _Bp,
344 size_t _Tp,
345 _UInt _Cp,
346 size_t _Lp,
347 _UInt _Fp>
348_LIBCPP_HIDE_FROM_ABI bool
349operator==(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
350 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y) {
351 if (__x.__i_ == __y.__i_)
352 return std::equal(__x.__x_, __x.__x_ + _Np, __y.__x_);
353 if (__x.__i_ == 0 || __y.__i_ == 0) {
354 size_t __j = std::min(_Np - __x.__i_, _Np - __y.__i_);
355 if (!std::equal(__x.__x_ + __x.__i_, __x.__x_ + __x.__i_ + __j, __y.__x_ + __y.__i_))
356 return false;
357 if (__x.__i_ == 0)
358 return std::equal(__x.__x_ + __j, __x.__x_ + _Np, __y.__x_);
359 return std::equal(__x.__x_, __x.__x_ + (_Np - __j), __y.__x_ + __j);
360 }
361 if (__x.__i_ < __y.__i_) {
362 size_t __j = _Np - __y.__i_;
363 if (!std::equal(__x.__x_ + __x.__i_, __x.__x_ + (__x.__i_ + __j), __y.__x_ + __y.__i_))
364 return false;
365 if (!std::equal(__x.__x_ + (__x.__i_ + __j), __x.__x_ + _Np, __y.__x_))
366 return false;
367 return std::equal(__x.__x_, __x.__x_ + __x.__i_, __y.__x_ + (_Np - (__x.__i_ + __j)));
368 }
369 size_t __j = _Np - __x.__i_;
370 if (!std::equal(__y.__x_ + __y.__i_, __y.__x_ + (__y.__i_ + __j), __x.__x_ + __x.__i_))
371 return false;
372 if (!std::equal(__y.__x_ + (__y.__i_ + __j), __y.__x_ + _Np, __x.__x_))
373 return false;
374 return std::equal(__y.__x_, __y.__x_ + __y.__i_, __x.__x_ + (_Np - (__y.__i_ + __j)));
375}
376
377template <class _UInt,
378 size_t _Wp,
379 size_t _Np,
380 size_t _Mp,
381 size_t _Rp,
382 _UInt _Ap,
383 size_t _Up,
384 _UInt _Dp,
385 size_t _Sp,
386 _UInt _Bp,
387 size_t _Tp,
388 _UInt _Cp,
389 size_t _Lp,
390 _UInt _Fp>
391inline _LIBCPP_HIDE_FROM_ABI bool
392operator!=(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
393 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y) {
394 return !(__x == __y);
395}
396
397template <class _CharT,
398 class _Traits,
399 class _UInt,
400 size_t _Wp,
401 size_t _Np,
402 size_t _Mp,
403 size_t _Rp,
404 _UInt _Ap,
405 size_t _Up,
406 _UInt _Dp,
407 size_t _Sp,
408 _UInt _Bp,
409 size_t _Tp,
410 _UInt _Cp,
411 size_t _Lp,
412 _UInt _Fp>
413_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
414operator<<(basic_ostream<_CharT, _Traits>& __os,
415 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x) {
416 __save_flags<_CharT, _Traits> __lx(__os);
417 typedef basic_ostream<_CharT, _Traits> _Ostream;
418 __os.flags(_Ostream::dec | _Ostream::left);
419 _CharT __sp = __os.widen(' ');
420 __os.fill(__sp);
421 __os << __x.__x_[__x.__i_];
422 for (size_t __j = __x.__i_ + 1; __j < _Np; ++__j)
423 __os << __sp << __x.__x_[__j];
424 for (size_t __j = 0; __j < __x.__i_; ++__j)
425 __os << __sp << __x.__x_[__j];
426 return __os;
427}
428
429template <class _CharT,
430 class _Traits,
431 class _UInt,
432 size_t _Wp,
433 size_t _Np,
434 size_t _Mp,
435 size_t _Rp,
436 _UInt _Ap,
437 size_t _Up,
438 _UInt _Dp,
439 size_t _Sp,
440 _UInt _Bp,
441 size_t _Tp,
442 _UInt _Cp,
443 size_t _Lp,
444 _UInt _Fp>
445_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
446operator>>(basic_istream<_CharT, _Traits>& __is,
447 mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x) {
448 __save_flags<_CharT, _Traits> __lx(__is);
449 typedef basic_istream<_CharT, _Traits> _Istream;
450 __is.flags(_Istream::dec | _Istream::skipws);
451 _UInt __t[_Np];
452 for (size_t __i = 0; __i < _Np; ++__i)
453 __is >> __t[__i];
454 if (!__is.fail()) {
455 for (size_t __i = 0; __i < _Np; ++__i)
456 __x.__x_[__i] = __t[__i];
457 __x.__i_ = 0;
458 }
459 return __is;
460}
461
462typedef mersenne_twister_engine<
463 uint_fast32_t,
464 32,
465 624,
466 397,
467 31,
468 0x9908b0df,
469 11,
470 0xffffffff,
471 7,
472 0x9d2c5680,
473 15,
474 0xefc60000,
475 18,
476 1812433253>
477 mt19937;
478typedef mersenne_twister_engine<
479 uint_fast64_t,
480 64,
481 312,
482 156,
483 31,
484 0xb5026f5aa96619e9ULL,
485 29,
486 0x5555555555555555ULL,
487 17,
488 0x71d67fffeda60000ULL,
489 37,
490 0xfff7eee000000000ULL,
491 43,
492 6364136223846793005ULL>
493 mt19937_64;
494
495_LIBCPP_END_NAMESPACE_STD
496
497_LIBCPP_POP_MACROS
498
499#endif // _LIBCPP___RANDOM_MERSENNE_TWISTER_ENGINE_H
500