xref: /freebsd/contrib/llvm-project/libcxx/include/ratio (revision 6be3386466ab79a84b48429ae66244f21526d3df)
1// -*- C++ -*-
2//===---------------------------- ratio -----------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_RATIO
11#define _LIBCPP_RATIO
12
13/*
14    ratio synopsis
15
16namespace std
17{
18
19template <intmax_t N, intmax_t D = 1>
20class ratio
21{
22public:
23    static constexpr intmax_t num;
24    static constexpr intmax_t den;
25    typedef ratio<num, den> type;
26};
27
28// ratio arithmetic
29template <class R1, class R2> using ratio_add = ...;
30template <class R1, class R2> using ratio_subtract = ...;
31template <class R1, class R2> using ratio_multiply = ...;
32template <class R1, class R2> using ratio_divide = ...;
33
34// ratio comparison
35template <class R1, class R2> struct ratio_equal;
36template <class R1, class R2> struct ratio_not_equal;
37template <class R1, class R2> struct ratio_less;
38template <class R1, class R2> struct ratio_less_equal;
39template <class R1, class R2> struct ratio_greater;
40template <class R1, class R2> struct ratio_greater_equal;
41
42// convenience SI typedefs
43typedef ratio<1, 1000000000000000000000000> yocto;  // not supported
44typedef ratio<1,    1000000000000000000000> zepto;  // not supported
45typedef ratio<1,       1000000000000000000> atto;
46typedef ratio<1,          1000000000000000> femto;
47typedef ratio<1,             1000000000000> pico;
48typedef ratio<1,                1000000000> nano;
49typedef ratio<1,                   1000000> micro;
50typedef ratio<1,                      1000> milli;
51typedef ratio<1,                       100> centi;
52typedef ratio<1,                        10> deci;
53typedef ratio<                       10, 1> deca;
54typedef ratio<                      100, 1> hecto;
55typedef ratio<                     1000, 1> kilo;
56typedef ratio<                  1000000, 1> mega;
57typedef ratio<               1000000000, 1> giga;
58typedef ratio<            1000000000000, 1> tera;
59typedef ratio<         1000000000000000, 1> peta;
60typedef ratio<      1000000000000000000, 1> exa;
61typedef ratio<   1000000000000000000000, 1> zetta;  // not supported
62typedef ratio<1000000000000000000000000, 1> yotta;  // not supported
63
64  // 20.11.5, ratio comparison
65  template <class R1, class R2> inline constexpr bool ratio_equal_v
66    = ratio_equal<R1, R2>::value;                                       // C++17
67  template <class R1, class R2> inline constexpr bool ratio_not_equal_v
68    = ratio_not_equal<R1, R2>::value;                                   // C++17
69  template <class R1, class R2> inline constexpr bool ratio_less_v
70    = ratio_less<R1, R2>::value;                                        // C++17
71  template <class R1, class R2> inline constexpr bool ratio_less_equal_v
72    = ratio_less_equal<R1, R2>::value;                                  // C++17
73  template <class R1, class R2> inline constexpr bool ratio_greater_v
74    = ratio_greater<R1, R2>::value;                                     // C++17
75  template <class R1, class R2> inline constexpr bool ratio_greater_equal_v
76    = ratio_greater_equal<R1, R2>::value;                               // C++17
77}
78*/
79
80#include <__config>
81#include <cstdint>
82#include <climits>
83#include <type_traits>
84
85#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
86#pragma GCC system_header
87#endif
88
89_LIBCPP_PUSH_MACROS
90#include <__undef_macros>
91
92
93_LIBCPP_BEGIN_NAMESPACE_STD
94
95// __static_gcd
96
97template <intmax_t _Xp, intmax_t _Yp>
98struct __static_gcd
99{
100    static const intmax_t value = __static_gcd<_Yp, _Xp % _Yp>::value;
101};
102
103template <intmax_t _Xp>
104struct __static_gcd<_Xp, 0>
105{
106    static const intmax_t value = _Xp;
107};
108
109template <>
110struct __static_gcd<0, 0>
111{
112    static const intmax_t value = 1;
113};
114
115// __static_lcm
116
117template <intmax_t _Xp, intmax_t _Yp>
118struct __static_lcm
119{
120    static const intmax_t value = _Xp / __static_gcd<_Xp, _Yp>::value * _Yp;
121};
122
123template <intmax_t _Xp>
124struct __static_abs
125{
126    static const intmax_t value = _Xp < 0 ? -_Xp : _Xp;
127};
128
129template <intmax_t _Xp>
130struct __static_sign
131{
132    static const intmax_t value = _Xp == 0 ? 0 : (_Xp < 0 ? -1 : 1);
133};
134
135template <intmax_t _Xp, intmax_t _Yp, intmax_t = __static_sign<_Yp>::value>
136class __ll_add;
137
138template <intmax_t _Xp, intmax_t _Yp>
139class __ll_add<_Xp, _Yp, 1>
140{
141    static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
142    static const intmax_t max = -min;
143
144    static_assert(_Xp <= max - _Yp, "overflow in __ll_add");
145public:
146    static const intmax_t value = _Xp + _Yp;
147};
148
149template <intmax_t _Xp, intmax_t _Yp>
150class __ll_add<_Xp, _Yp, 0>
151{
152public:
153    static const intmax_t value = _Xp;
154};
155
156template <intmax_t _Xp, intmax_t _Yp>
157class __ll_add<_Xp, _Yp, -1>
158{
159    static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
160    static const intmax_t max = -min;
161
162    static_assert(min - _Yp <= _Xp, "overflow in __ll_add");
163public:
164    static const intmax_t value = _Xp + _Yp;
165};
166
167template <intmax_t _Xp, intmax_t _Yp, intmax_t = __static_sign<_Yp>::value>
168class __ll_sub;
169
170template <intmax_t _Xp, intmax_t _Yp>
171class __ll_sub<_Xp, _Yp, 1>
172{
173    static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
174    static const intmax_t max = -min;
175
176    static_assert(min + _Yp <= _Xp, "overflow in __ll_sub");
177public:
178    static const intmax_t value = _Xp - _Yp;
179};
180
181template <intmax_t _Xp, intmax_t _Yp>
182class __ll_sub<_Xp, _Yp, 0>
183{
184public:
185    static const intmax_t value = _Xp;
186};
187
188template <intmax_t _Xp, intmax_t _Yp>
189class __ll_sub<_Xp, _Yp, -1>
190{
191    static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1;
192    static const intmax_t max = -min;
193
194    static_assert(_Xp <= max + _Yp, "overflow in __ll_sub");
195public:
196    static const intmax_t value = _Xp - _Yp;
197};
198
199template <intmax_t _Xp, intmax_t _Yp>
200class __ll_mul
201{
202    static const intmax_t nan = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1));
203    static const intmax_t min = nan + 1;
204    static const intmax_t max = -min;
205    static const intmax_t __a_x = __static_abs<_Xp>::value;
206    static const intmax_t __a_y = __static_abs<_Yp>::value;
207
208    static_assert(_Xp != nan && _Yp != nan && __a_x <= max / __a_y, "overflow in __ll_mul");
209public:
210    static const intmax_t value = _Xp * _Yp;
211};
212
213template <intmax_t _Yp>
214class __ll_mul<0, _Yp>
215{
216public:
217    static const intmax_t value = 0;
218};
219
220template <intmax_t _Xp>
221class __ll_mul<_Xp, 0>
222{
223public:
224    static const intmax_t value = 0;
225};
226
227template <>
228class __ll_mul<0, 0>
229{
230public:
231    static const intmax_t value = 0;
232};
233
234// Not actually used but left here in case needed in future maintenance
235template <intmax_t _Xp, intmax_t _Yp>
236class __ll_div
237{
238    static const intmax_t nan = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1));
239    static const intmax_t min = nan + 1;
240    static const intmax_t max = -min;
241
242    static_assert(_Xp != nan && _Yp != nan && _Yp != 0, "overflow in __ll_div");
243public:
244    static const intmax_t value = _Xp / _Yp;
245};
246
247template <intmax_t _Num, intmax_t _Den = 1>
248class _LIBCPP_TEMPLATE_VIS ratio
249{
250    static_assert(__static_abs<_Num>::value >= 0, "ratio numerator is out of range");
251    static_assert(_Den != 0, "ratio divide by 0");
252    static_assert(__static_abs<_Den>::value >  0, "ratio denominator is out of range");
253    static _LIBCPP_CONSTEXPR const intmax_t __na = __static_abs<_Num>::value;
254    static _LIBCPP_CONSTEXPR const intmax_t __da = __static_abs<_Den>::value;
255    static _LIBCPP_CONSTEXPR const intmax_t __s = __static_sign<_Num>::value * __static_sign<_Den>::value;
256    static _LIBCPP_CONSTEXPR const intmax_t __gcd = __static_gcd<__na, __da>::value;
257public:
258    static _LIBCPP_CONSTEXPR const intmax_t num = __s * __na / __gcd;
259    static _LIBCPP_CONSTEXPR const intmax_t den = __da / __gcd;
260
261    typedef ratio<num, den> type;
262};
263
264template <intmax_t _Num, intmax_t _Den>
265_LIBCPP_CONSTEXPR const intmax_t ratio<_Num, _Den>::num;
266
267template <intmax_t _Num, intmax_t _Den>
268_LIBCPP_CONSTEXPR const intmax_t ratio<_Num, _Den>::den;
269
270template <class _Tp>                    struct __is_ratio                     : false_type {};
271template <intmax_t _Num, intmax_t _Den> struct __is_ratio<ratio<_Num, _Den> > : true_type  {};
272
273typedef ratio<1LL, 1000000000000000000LL> atto;
274typedef ratio<1LL,    1000000000000000LL> femto;
275typedef ratio<1LL,       1000000000000LL> pico;
276typedef ratio<1LL,          1000000000LL> nano;
277typedef ratio<1LL,             1000000LL> micro;
278typedef ratio<1LL,                1000LL> milli;
279typedef ratio<1LL,                 100LL> centi;
280typedef ratio<1LL,                  10LL> deci;
281typedef ratio<                 10LL, 1LL> deca;
282typedef ratio<                100LL, 1LL> hecto;
283typedef ratio<               1000LL, 1LL> kilo;
284typedef ratio<            1000000LL, 1LL> mega;
285typedef ratio<         1000000000LL, 1LL> giga;
286typedef ratio<      1000000000000LL, 1LL> tera;
287typedef ratio<   1000000000000000LL, 1LL> peta;
288typedef ratio<1000000000000000000LL, 1LL> exa;
289
290template <class _R1, class _R2>
291struct __ratio_multiply
292{
293private:
294    static const intmax_t __gcd_n1_d2 = __static_gcd<_R1::num, _R2::den>::value;
295    static const intmax_t __gcd_d1_n2 = __static_gcd<_R1::den, _R2::num>::value;
296public:
297    typedef typename ratio
298        <
299            __ll_mul<_R1::num / __gcd_n1_d2, _R2::num / __gcd_d1_n2>::value,
300            __ll_mul<_R2::den / __gcd_n1_d2, _R1::den / __gcd_d1_n2>::value
301        >::type type;
302};
303
304#ifndef _LIBCPP_CXX03_LANG
305
306template <class _R1, class _R2> using ratio_multiply
307                                    = typename __ratio_multiply<_R1, _R2>::type;
308
309#else  // _LIBCPP_CXX03_LANG
310
311template <class _R1, class _R2>
312struct _LIBCPP_TEMPLATE_VIS ratio_multiply
313    : public __ratio_multiply<_R1, _R2>::type {};
314
315#endif  // _LIBCPP_CXX03_LANG
316
317template <class _R1, class _R2>
318struct __ratio_divide
319{
320private:
321    static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
322    static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
323public:
324    typedef typename ratio
325        <
326            __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value,
327            __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value
328        >::type type;
329};
330
331#ifndef _LIBCPP_CXX03_LANG
332
333template <class _R1, class _R2> using ratio_divide
334                                      = typename __ratio_divide<_R1, _R2>::type;
335
336#else  // _LIBCPP_CXX03_LANG
337
338template <class _R1, class _R2>
339struct _LIBCPP_TEMPLATE_VIS ratio_divide
340    : public __ratio_divide<_R1, _R2>::type {};
341
342#endif  // _LIBCPP_CXX03_LANG
343
344template <class _R1, class _R2>
345struct __ratio_add
346{
347private:
348    static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
349    static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
350public:
351    typedef typename ratio_multiply
352        <
353            ratio<__gcd_n1_n2, _R1::den / __gcd_d1_d2>,
354            ratio
355            <
356                __ll_add
357                <
358                    __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value,
359                    __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value
360                >::value,
361                _R2::den
362            >
363        >::type type;
364};
365
366#ifndef _LIBCPP_CXX03_LANG
367
368template <class _R1, class _R2> using ratio_add
369                                         = typename __ratio_add<_R1, _R2>::type;
370
371#else  // _LIBCPP_CXX03_LANG
372
373template <class _R1, class _R2>
374struct _LIBCPP_TEMPLATE_VIS ratio_add
375    : public __ratio_add<_R1, _R2>::type {};
376
377#endif  // _LIBCPP_CXX03_LANG
378
379template <class _R1, class _R2>
380struct __ratio_subtract
381{
382private:
383    static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
384    static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
385public:
386    typedef typename ratio_multiply
387        <
388            ratio<__gcd_n1_n2, _R1::den / __gcd_d1_d2>,
389            ratio
390            <
391                __ll_sub
392                <
393                    __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value,
394                    __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value
395                >::value,
396                _R2::den
397            >
398        >::type type;
399};
400
401#ifndef _LIBCPP_CXX03_LANG
402
403template <class _R1, class _R2> using ratio_subtract
404                                    = typename __ratio_subtract<_R1, _R2>::type;
405
406#else  // _LIBCPP_CXX03_LANG
407
408template <class _R1, class _R2>
409struct _LIBCPP_TEMPLATE_VIS ratio_subtract
410    : public __ratio_subtract<_R1, _R2>::type {};
411
412#endif  // _LIBCPP_CXX03_LANG
413
414// ratio_equal
415
416template <class _R1, class _R2>
417struct _LIBCPP_TEMPLATE_VIS ratio_equal
418    : public _LIBCPP_BOOL_CONSTANT((_R1::num == _R2::num && _R1::den == _R2::den)) {};
419
420template <class _R1, class _R2>
421struct _LIBCPP_TEMPLATE_VIS ratio_not_equal
422    : public _LIBCPP_BOOL_CONSTANT((!ratio_equal<_R1, _R2>::value)) {};
423
424// ratio_less
425
426template <class _R1, class _R2, bool _Odd = false,
427          intmax_t _Q1 = _R1::num / _R1::den, intmax_t _M1 = _R1::num % _R1::den,
428          intmax_t _Q2 = _R2::num / _R2::den, intmax_t _M2 = _R2::num % _R2::den>
429struct __ratio_less1
430{
431    static const bool value = _Odd ? _Q2 < _Q1 : _Q1 < _Q2;
432};
433
434template <class _R1, class _R2, bool _Odd, intmax_t _Qp>
435struct __ratio_less1<_R1, _R2, _Odd, _Qp, 0, _Qp, 0>
436{
437    static const bool value = false;
438};
439
440template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M2>
441struct __ratio_less1<_R1, _R2, _Odd, _Qp, 0, _Qp, _M2>
442{
443    static const bool value = !_Odd;
444};
445
446template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M1>
447struct __ratio_less1<_R1, _R2, _Odd, _Qp, _M1, _Qp, 0>
448{
449    static const bool value = _Odd;
450};
451
452template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M1,
453                                                        intmax_t _M2>
454struct __ratio_less1<_R1, _R2, _Odd, _Qp, _M1, _Qp, _M2>
455{
456    static const bool value = __ratio_less1<ratio<_R1::den, _M1>,
457                                            ratio<_R2::den, _M2>, !_Odd>::value;
458};
459
460template <class _R1, class _R2, intmax_t _S1 = __static_sign<_R1::num>::value,
461                                intmax_t _S2 = __static_sign<_R2::num>::value>
462struct __ratio_less
463{
464    static const bool value = _S1 < _S2;
465};
466
467template <class _R1, class _R2>
468struct __ratio_less<_R1, _R2, 1LL, 1LL>
469{
470    static const bool value = __ratio_less1<_R1, _R2>::value;
471};
472
473template <class _R1, class _R2>
474struct __ratio_less<_R1, _R2, -1LL, -1LL>
475{
476    static const bool value = __ratio_less1<ratio<-_R2::num, _R2::den>, ratio<-_R1::num, _R1::den> >::value;
477};
478
479template <class _R1, class _R2>
480struct _LIBCPP_TEMPLATE_VIS ratio_less
481    : public _LIBCPP_BOOL_CONSTANT((__ratio_less<_R1, _R2>::value)) {};
482
483template <class _R1, class _R2>
484struct _LIBCPP_TEMPLATE_VIS ratio_less_equal
485    : public _LIBCPP_BOOL_CONSTANT((!ratio_less<_R2, _R1>::value)) {};
486
487template <class _R1, class _R2>
488struct _LIBCPP_TEMPLATE_VIS ratio_greater
489    : public _LIBCPP_BOOL_CONSTANT((ratio_less<_R2, _R1>::value)) {};
490
491template <class _R1, class _R2>
492struct _LIBCPP_TEMPLATE_VIS ratio_greater_equal
493    : public _LIBCPP_BOOL_CONSTANT((!ratio_less<_R1, _R2>::value)) {};
494
495template <class _R1, class _R2>
496struct __ratio_gcd
497{
498    typedef ratio<__static_gcd<_R1::num, _R2::num>::value,
499                  __static_lcm<_R1::den, _R2::den>::value> type;
500};
501
502#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
503template <class _R1, class _R2>
504_LIBCPP_INLINE_VAR _LIBCPP_CONSTEXPR bool ratio_equal_v
505    = ratio_equal<_R1, _R2>::value;
506
507template <class _R1, class _R2>
508_LIBCPP_INLINE_VAR _LIBCPP_CONSTEXPR bool ratio_not_equal_v
509    = ratio_not_equal<_R1, _R2>::value;
510
511template <class _R1, class _R2>
512_LIBCPP_INLINE_VAR _LIBCPP_CONSTEXPR bool ratio_less_v
513    = ratio_less<_R1, _R2>::value;
514
515template <class _R1, class _R2>
516_LIBCPP_INLINE_VAR _LIBCPP_CONSTEXPR bool ratio_less_equal_v
517    = ratio_less_equal<_R1, _R2>::value;
518
519template <class _R1, class _R2>
520_LIBCPP_INLINE_VAR _LIBCPP_CONSTEXPR bool ratio_greater_v
521    = ratio_greater<_R1, _R2>::value;
522
523template <class _R1, class _R2>
524_LIBCPP_INLINE_VAR _LIBCPP_CONSTEXPR bool ratio_greater_equal_v
525    = ratio_greater_equal<_R1, _R2>::value;
526#endif
527
528_LIBCPP_END_NAMESPACE_STD
529
530_LIBCPP_POP_MACROS
531
532#endif  // _LIBCPP_RATIO
533