1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
|
// <bit> -*- C++ -*-
// Copyright (C) 2018 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file include/bit
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_BIT
#define _GLIBCXX_BIT 1
#pragma GCC system_header
#if __cplusplus >= 201402L
#include <type_traits>
#include <limits>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Tp>
constexpr _Tp
__rotl(_Tp __x, unsigned int __s) noexcept
{
constexpr auto _Nd = numeric_limits<_Tp>::digits;
const unsigned __sN = __s % _Nd;
return (__x << __sN) | (__x >> ((_Nd - __sN) % _Nd));
}
template<typename _Tp>
constexpr _Tp
__rotr(_Tp __x, unsigned int __s) noexcept
{
constexpr auto _Nd = numeric_limits<_Tp>::digits;
const unsigned __sN = __s % _Nd;
return (__x >> __sN) | (__x << ((_Nd - __sN) % _Nd));
}
template<typename _Tp>
constexpr int
__countl_zero(_Tp __x) noexcept
{
constexpr auto _Nd = numeric_limits<_Tp>::digits;
if (__x == 0)
return _Nd;
constexpr auto _Nd_ull = numeric_limits<unsigned long long>::digits;
constexpr auto _Nd_ul = numeric_limits<unsigned long>::digits;
constexpr auto _Nd_u = numeric_limits<unsigned>::digits;
if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u)
{
constexpr int __diff = _Nd_u - _Nd;
return __builtin_clz(__x) - __diff;
}
else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul)
{
constexpr int __diff = _Nd_ul - _Nd;
return __builtin_clzl(__x) - __diff;
}
else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull)
{
constexpr int __diff = _Nd_ull - _Nd;
return __builtin_clzll(__x) - __diff;
}
else // (_Nd > _Nd_ull)
{
static_assert(_Nd <= (2 * _Nd_ull),
"Maximum supported integer size is 128-bit");
unsigned long long __high = __x >> _Nd_ull;
if (__high != 0)
{
constexpr int __diff = (2 * _Nd_ull) - _Nd;
return __builtin_clzll(__high) - __diff;
}
constexpr auto __max_ull = numeric_limits<unsigned long long>::max();
unsigned long long __low = __x & __max_ull;
return (_Nd - _Nd_ull) + __builtin_clzll(__low);
}
}
template<typename _Tp>
constexpr int
__countl_one(_Tp __x) noexcept
{
if (__x == numeric_limits<_Tp>::max())
return numeric_limits<_Tp>::digits;
return std::__countl_zero<_Tp>((_Tp)~__x);
}
template<typename _Tp>
constexpr int
__countr_zero(_Tp __x) noexcept
{
constexpr auto _Nd = numeric_limits<_Tp>::digits;
if (__x == 0)
return _Nd;
constexpr auto _Nd_ull = numeric_limits<unsigned long long>::digits;
constexpr auto _Nd_ul = numeric_limits<unsigned long>::digits;
constexpr auto _Nd_u = numeric_limits<unsigned>::digits;
if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u)
return __builtin_ctz(__x);
else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul)
return __builtin_ctzl(__x);
else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull)
return __builtin_ctzll(__x);
else // (_Nd > _Nd_ull)
{
static_assert(_Nd <= (2 * _Nd_ull),
"Maximum supported integer size is 128-bit");
constexpr auto __max_ull = numeric_limits<unsigned long long>::max();
unsigned long long __low = __x & __max_ull;
if (__low != 0)
return __builtin_ctzll(__low);
unsigned long long __high = __x >> _Nd_ull;
return __builtin_ctzll(__high) + _Nd_ull;
}
}
template<typename _Tp>
constexpr int
__countr_one(_Tp __x) noexcept
{
if (__x == numeric_limits<_Tp>::max())
return numeric_limits<_Tp>::digits;
return std::__countr_zero((_Tp)~__x);
}
template<typename _Tp>
constexpr int
__popcount(_Tp __x) noexcept
{
constexpr auto _Nd = numeric_limits<_Tp>::digits;
if (__x == 0)
return 0;
constexpr auto _Nd_ull = numeric_limits<unsigned long long>::digits;
constexpr auto _Nd_ul = numeric_limits<unsigned long>::digits;
constexpr auto _Nd_u = numeric_limits<unsigned>::digits;
if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u)
return __builtin_popcount(__x);
else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul)
return __builtin_popcountl(__x);
else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull)
return __builtin_popcountll(__x);
else // (_Nd > _Nd_ull)
{
static_assert(_Nd <= (2 * _Nd_ull),
"Maximum supported integer size is 128-bit");
constexpr auto __max_ull = numeric_limits<unsigned long long>::max();
unsigned long long __low = __x & __max_ull;
unsigned long long __high = __x >> _Nd_ull;
return __builtin_popcountll(__low) + __builtin_popcountll(__high);
}
}
template<typename _Tp>
constexpr bool
__ispow2(_Tp __x) noexcept
{ return std::__popcount(__x) == 1; }
template<typename _Tp>
constexpr _Tp
__ceil2(_Tp __x) noexcept
{
constexpr auto _Nd = numeric_limits<_Tp>::digits;
if (__x == 0)
return 1;
return (_Tp)1u << (_Nd - std::__countl_zero((_Tp)(__x - 1u)));
}
template<typename _Tp>
constexpr _Tp
__floor2(_Tp __x) noexcept
{
constexpr auto _Nd = numeric_limits<_Tp>::digits;
if (__x == 0)
return 0;
return (_Tp)1u << (_Nd - std::__countl_zero((_Tp)(__x >> 1)));
}
template<typename _Tp>
constexpr _Tp
__log2p1(_Tp __x) noexcept
{
constexpr auto _Nd = numeric_limits<_Tp>::digits;
return _Nd - std::__countl_zero(__x);
}
#if __cplusplus > 201703L
template<typename _Tp, typename _Up, bool = is_integral_v<_Tp>>
struct _If_is_unsigned_integer_type { };
template<typename _Up>
struct _If_is_unsigned_integer_type<bool, _Up, true> { };
template<typename _Tp, typename _Up>
struct _If_is_unsigned_integer_type<_Tp, _Up, true>
: enable_if<is_same_v<_Tp, make_unsigned_t<_Tp>>, _Up> { };
template<typename _Tp, typename _Up = _Tp>
using _If_is_unsigned_integer
= typename _If_is_unsigned_integer_type<remove_cv_t<_Tp>, _Up>::type;
#if ! __STRICT_ANSI__
// [bitops.rot], rotating
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp>
rotl(_Tp __x, unsigned int __s) noexcept
{ return std::__rotl(__x, __s); }
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp>
rotr(_Tp __x, unsigned int __s) noexcept
{ return std::__rotr(__x, __s); }
// [bitops.count], counting
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp, int>
countl_zero(_Tp __x) noexcept
{ return std::__countl_zero(__x); }
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp, int>
countl_one(_Tp __x) noexcept
{ return std::__countl_one(__x); }
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp, int>
countr_zero(_Tp __x) noexcept
{ return std::__countr_zero(__x); }
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp, int>
countr_one(_Tp __x) noexcept
{ return std::__countr_one(__x); }
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp, int>
popcount(_Tp __x) noexcept
{ return std::__popcount(__x); }
#endif
// Integral power-of-two operations
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp, bool>
ispow2(_Tp __x) noexcept
{ return std::__ispow2(__x); }
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp>
ceil2(_Tp __x) noexcept
{ return std::__ceil2(__x); }
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp>
floor2(_Tp __x) noexcept
{ return std::__floor2(__x); }
template<typename _Tp>
constexpr _If_is_unsigned_integer<_Tp>
log2p1(_Tp __x) noexcept
{ return std::__log2p1(__x); }
#if ! __STRICT_ANSI__
enum class byte : unsigned char;
constexpr byte
rotl(byte __x, unsigned int __s) noexcept
{ return (byte)std::__rotl((unsigned char)__x, __s); }
constexpr byte
rotr(byte __x, unsigned int __s) noexcept
{ return (byte)std::__rotr((unsigned char)__x, __s); }
constexpr int
countl_zero(byte __x) noexcept
{ return std::__countl_zero((unsigned char)__x); }
constexpr int
countl_one(byte __x) noexcept
{ return std::__countl_one((unsigned char)__x); }
constexpr int
countr_zero(byte __x) noexcept
{ return std::__countr_zero((unsigned char)__x); }
constexpr int
countr_one(byte __x) noexcept
{ return std::__countr_one((unsigned char)__x); }
constexpr int
popcount(byte __x) noexcept
{ return std::__popcount((unsigned char)__x); }
constexpr bool
ispow2(byte __x) noexcept
{ return std::__ispow2((unsigned char)__x); }
constexpr byte
ceil2(byte __x) noexcept
{ return (byte)std::__ceil2((unsigned char)__x); }
constexpr byte
floor2(byte __x) noexcept
{ return (byte)std::__floor2((unsigned char)__x); }
constexpr byte
log2p1(byte __x) noexcept
{ return (byte)std::__log2p1((unsigned char)__x); }
#endif
#endif // C++2a
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // C++14
#endif // _GLIBCXX_BIT
|
