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 __update_all_states();
185 }
186 template <class _Sseq, __enable_if_t<__is_seed_sequence_v<_Sseq, mersenne_twister_engine>, int> = 0>
187 _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
188 const unsigned __k = 1 + (__w - 1) / 32;
189 static_assert(__k <= 2);
190 uint32_t __ar[__n * __k];
191 __q.generate(__ar, __ar + __n * __k);
192 for (size_t __i = 0; __i < __n; ++__i) {
193 if _LIBCPP_CONSTEXPR (__k == 1) {
194 __x_[__i] = static_cast<result_type>(__ar[__i] & _Max);
195 } else {
196 __x_[__i] = static_cast<result_type>((__ar[2 * __i] + ((uint64_t)__ar[2 * __i + 1] << 32)) & _Max);
197 }
198 }
199 const result_type __mask = __r == _Dt ? result_type(~0) : (result_type(1) << __r) - result_type(1);
200 __i_ = 0;
201 if ((__x_[0] & ~__mask) == 0) {
202 size_t __i = 1;
203 for (; __i < __n; ++__i)
204 if (__x_[__i] != 0)
205 break;
206 if (__i == __n)
207 __x_[0] = result_type(1) << (__w - 1);
208 }
209 __update_all_states();
210 }
211
212 void __update_state(size_t __i, size_t __k) {
213 const size_t __j = (__i + 1) % __n;
214 const result_type __mask = __r == _Dt ? result_type(~0) : (result_type(1) << __r) - result_type(1);
215 const result_type __yp = (__x_[__i] & ~__mask) | (__x_[__j] & __mask);
216 __x_[__i] = __x_[__k] ^ __rshift<1>(__yp) ^ (__a * (__yp & 1));
217 }
218
219 void __update_state(size_t __i) { __update_state(__i, (__i + __m) % __n); }
220
221 void __update_all_states() {
222 size_t __i = 0;
223 // This is split into two loops to help the compiler vectorize the code
224 for (; __i != (__n - __m); ++__i)
225 __update_state(__i);
226 for (size_t __j = 0; __i != __n; ++__i, ++__j)
227 __update_state(__i, __j);
228 }
229
230 // generating functions
231 [[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI result_type operator()() {
232 result_type __val = __x_[__i_];
233 if (++__i_ == __n) [[__unlikely__]] {
234 __update_all_states();
235 __i_ = 0;
236 }
237 result_type __z = __val ^ (__rshift<__u>(__val) & __d);
238 __z ^= __lshift<__s>(__z) & __b;
239 __z ^= __lshift<__t>(__z) & __c;
240 return __z ^ __rshift<__l>(__z);
241 }
242
243 _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
244 for (; __z; --__z)
245 (void)operator()();
246 }
247
248 template <class _UInt,
249 size_t _Wp,
250 size_t _Np,
251 size_t _Mp,
252 size_t _Rp,
253 _UInt _Ap,
254 size_t _Up,
255 _UInt _Dp,
256 size_t _Sp,
257 _UInt _Bp,
258 size_t _Tp,
259 _UInt _Cp,
260 size_t _Lp,
261 _UInt _Fp>
262 friend bool operator==(
263 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
264 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y);
265
266 template <class _CharT,
267 class _Traits,
268 class _UInt,
269 size_t _Wp,
270 size_t _Np,
271 size_t _Mp,
272 size_t _Rp,
273 _UInt _Ap,
274 size_t _Up,
275 _UInt _Dp,
276 size_t _Sp,
277 _UInt _Bp,
278 size_t _Tp,
279 _UInt _Cp,
280 size_t _Lp,
281 _UInt _Fp>
282 friend basic_ostream<_CharT, _Traits>& operator<<(
283 basic_ostream<_CharT, _Traits>& __os,
284 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
285
286 template <class _CharT,
287 class _Traits,
288 class _UInt,
289 size_t _Wp,
290 size_t _Np,
291 size_t _Mp,
292 size_t _Rp,
293 _UInt _Ap,
294 size_t _Up,
295 _UInt _Dp,
296 size_t _Sp,
297 _UInt _Bp,
298 size_t _Tp,
299 _UInt _Cp,
300 size_t _Lp,
301 _UInt _Fp>
302 friend basic_istream<_CharT, _Traits>&
303 operator>>(basic_istream<_CharT, _Traits>& __is,
304 mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x);
305
306private:
307 template <size_t __count>
308 _LIBCPP_HIDE_FROM_ABI static result_type __lshift(result_type __x) {
309 if _LIBCPP_CONSTEXPR (__count < __w) {
310 return (__x << __count) & _Max;
311 } else {
312 return result_type(0);
313 }
314 }
315
316 template <size_t __count>
317 _LIBCPP_HIDE_FROM_ABI static result_type __rshift(result_type __x) {
318 if _LIBCPP_CONSTEXPR (__count < _Dt) {
319 return __x >> __count;
320 } else {
321 return result_type(0);
322 }
323 }
324};
325
326template <class _UInt,
327 size_t _Wp,
328 size_t _Np,
329 size_t _Mp,
330 size_t _Rp,
331 _UInt _Ap,
332 size_t _Up,
333 _UInt _Dp,
334 size_t _Sp,
335 _UInt _Bp,
336 size_t _Tp,
337 _UInt _Cp,
338 size_t _Lp,
339 _UInt _Fp>
340_LIBCPP_HIDE_FROM_ABI bool
341operator==(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
342 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y) {
343 if (__x.__i_ == __y.__i_)
344 return std::equal(__x.__x_, __x.__x_ + _Np, __y.__x_);
345 if (__x.__i_ == 0 || __y.__i_ == 0) {
346 size_t __j = std::min(_Np - __x.__i_, _Np - __y.__i_);
347 if (!std::equal(__x.__x_ + __x.__i_, __x.__x_ + __x.__i_ + __j, __y.__x_ + __y.__i_))
348 return false;
349 if (__x.__i_ == 0)
350 return std::equal(__x.__x_ + __j, __x.__x_ + _Np, __y.__x_);
351 return std::equal(__x.__x_, __x.__x_ + (_Np - __j), __y.__x_ + __j);
352 }
353 if (__x.__i_ < __y.__i_) {
354 size_t __j = _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 (!std::equal(__x.__x_ + (__x.__i_ + __j), __x.__x_ + _Np, __y.__x_))
358 return false;
359 return std::equal(__x.__x_, __x.__x_ + __x.__i_, __y.__x_ + (_Np - (__x.__i_ + __j)));
360 }
361 size_t __j = _Np - __x.__i_;
362 if (!std::equal(__y.__x_ + __y.__i_, __y.__x_ + (__y.__i_ + __j), __x.__x_ + __x.__i_))
363 return false;
364 if (!std::equal(__y.__x_ + (__y.__i_ + __j), __y.__x_ + _Np, __x.__x_))
365 return false;
366 return std::equal(__y.__x_, __y.__x_ + __y.__i_, __x.__x_ + (_Np - (__y.__i_ + __j)));
367}
368
369template <class _UInt,
370 size_t _Wp,
371 size_t _Np,
372 size_t _Mp,
373 size_t _Rp,
374 _UInt _Ap,
375 size_t _Up,
376 _UInt _Dp,
377 size_t _Sp,
378 _UInt _Bp,
379 size_t _Tp,
380 _UInt _Cp,
381 size_t _Lp,
382 _UInt _Fp>
383inline _LIBCPP_HIDE_FROM_ABI bool
384operator!=(const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x,
385 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __y) {
386 return !(__x == __y);
387}
388
389template <class _CharT,
390 class _Traits,
391 class _UInt,
392 size_t _Wp,
393 size_t _Np,
394 size_t _Mp,
395 size_t _Rp,
396 _UInt _Ap,
397 size_t _Up,
398 _UInt _Dp,
399 size_t _Sp,
400 _UInt _Bp,
401 size_t _Tp,
402 _UInt _Cp,
403 size_t _Lp,
404 _UInt _Fp>
405_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
406operator<<(basic_ostream<_CharT, _Traits>& __os,
407 const mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x) {
408 __save_flags<_CharT, _Traits> __lx(__os);
409 typedef basic_ostream<_CharT, _Traits> _Ostream;
410 __os.flags(_Ostream::dec | _Ostream::left);
411 _CharT __sp = __os.widen(' ');
412 __os.fill(__sp);
413 __os << __x.__x_[__x.__i_];
414 for (size_t __j = __x.__i_ + 1; __j < _Np; ++__j)
415 __os << __sp << __x.__x_[__j];
416 for (size_t __j = 0; __j < __x.__i_; ++__j)
417 __os << __sp << __x.__x_[__j];
418 return __os;
419}
420
421template <class _CharT,
422 class _Traits,
423 class _UInt,
424 size_t _Wp,
425 size_t _Np,
426 size_t _Mp,
427 size_t _Rp,
428 _UInt _Ap,
429 size_t _Up,
430 _UInt _Dp,
431 size_t _Sp,
432 _UInt _Bp,
433 size_t _Tp,
434 _UInt _Cp,
435 size_t _Lp,
436 _UInt _Fp>
437_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
438operator>>(basic_istream<_CharT, _Traits>& __is,
439 mersenne_twister_engine<_UInt, _Wp, _Np, _Mp, _Rp, _Ap, _Up, _Dp, _Sp, _Bp, _Tp, _Cp, _Lp, _Fp>& __x) {
440 __save_flags<_CharT, _Traits> __lx(__is);
441 typedef basic_istream<_CharT, _Traits> _Istream;
442 __is.flags(_Istream::dec | _Istream::skipws);
443 _UInt __t[_Np];
444 for (size_t __i = 0; __i < _Np; ++__i)
445 __is >> __t[__i];
446 if (!__is.fail()) {
447 for (size_t __i = 0; __i < _Np; ++__i)
448 __x.__x_[__i] = __t[__i];
449 __x.__i_ = 0;
450 }
451 return __is;
452}
453
454typedef mersenne_twister_engine<
455 uint_fast32_t,
456 32,
457 624,
458 397,
459 31,
460 0x9908b0df,
461 11,
462 0xffffffff,
463 7,
464 0x9d2c5680,
465 15,
466 0xefc60000,
467 18,
468 1812433253>
469 mt19937;
470typedef mersenne_twister_engine<
471 uint_fast64_t,
472 64,
473 312,
474 156,
475 31,
476 0xb5026f5aa96619e9ULL,
477 29,
478 0x5555555555555555ULL,
479 17,
480 0x71d67fffeda60000ULL,
481 37,
482 0xfff7eee000000000ULL,
483 43,
484 6364136223846793005ULL>
485 mt19937_64;
486
487_LIBCPP_END_NAMESPACE_STD
488
489_LIBCPP_POP_MACROS
490
491#endif // _LIBCPP___RANDOM_MERSENNE_TWISTER_ENGINE_H
492