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1// -*- C++ -*-
2//===---------------------------- chrono ----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_CHRONO
12#define _LIBCPP_CHRONO
13
14/*
15    chrono synopsis
16
17namespace std
18{
19namespace chrono
20{
21
22template <class ToDuration, class Rep, class Period>
23constexpr
24ToDuration
25duration_cast(const duration<Rep, Period>& fd);
26
27template <class Rep> struct treat_as_floating_point : is_floating_point<Rep> {};
28
29template <class Rep> constexpr bool treat_as_floating_point_v
30    = treat_as_floating_point<Rep>::value;                       // C++17
31
32template <class Rep>
33struct duration_values
34{
35public:
36    static constexpr Rep zero();
37    static constexpr Rep max();
38    static constexpr Rep min();
39};
40
41// duration
42
43template <class Rep, class Period = ratio<1>>
44class duration
45{
46    static_assert(!__is_duration<Rep>::value, "A duration representation can not be a duration");
47    static_assert(__is_ratio<Period>::value, "Second template parameter of duration must be a std::ratio");
48    static_assert(Period::num > 0, "duration period must be positive");
49public:
50    typedef Rep rep;
51    typedef Period period;
52
53    constexpr duration() = default;
54    template <class Rep2>
55        constexpr explicit duration(const Rep2& r,
56            typename enable_if
57            <
58               is_convertible<Rep2, rep>::value &&
59               (treat_as_floating_point<rep>::value ||
60               !treat_as_floating_point<rep>::value && !treat_as_floating_point<Rep2>::value)
61            >::type* = 0);
62
63    // conversions
64    template <class Rep2, class Period2>
65        constexpr duration(const duration<Rep2, Period2>& d,
66            typename enable_if
67            <
68                treat_as_floating_point<rep>::value ||
69                ratio_divide<Period2, period>::type::den == 1
70            >::type* = 0);
71
72    // observer
73
74    constexpr rep count() const;
75
76    // arithmetic
77
78    constexpr duration  operator+() const;
79    constexpr duration  operator-() const;
80    constexpr duration& operator++();
81    constexpr duration  operator++(int);
82    constexpr duration& operator--();
83    constexpr duration  operator--(int);
84
85    constexpr duration& operator+=(const duration& d);
86    constexpr duration& operator-=(const duration& d);
87
88    duration& operator*=(const rep& rhs);
89    duration& operator/=(const rep& rhs);
90
91    // special values
92
93    static constexpr duration zero();
94    static constexpr duration min();
95    static constexpr duration max();
96};
97
98typedef duration<long long,         nano> nanoseconds;
99typedef duration<long long,        micro> microseconds;
100typedef duration<long long,        milli> milliseconds;
101typedef duration<long long              > seconds;
102typedef duration<     long, ratio<  60> > minutes;
103typedef duration<     long, ratio<3600> > hours;
104
105template <class Clock, class Duration = typename Clock::duration>
106class time_point
107{
108public:
109    typedef Clock                     clock;
110    typedef Duration                  duration;
111    typedef typename duration::rep    rep;
112    typedef typename duration::period period;
113private:
114    duration d_;  // exposition only
115
116public:
117    time_point();  // has value "epoch" // constexpr in C++14
118    explicit time_point(const duration& d);  // same as time_point() + d // constexpr in C++14
119
120    // conversions
121    template <class Duration2>
122       time_point(const time_point<clock, Duration2>& t); // constexpr in C++14
123
124    // observer
125
126    duration time_since_epoch() const; // constexpr in C++14
127
128    // arithmetic
129
130    time_point& operator+=(const duration& d);
131    time_point& operator-=(const duration& d);
132
133    // special values
134
135    static constexpr time_point min();
136    static constexpr time_point max();
137};
138
139} // chrono
140
141// common_type traits
142template <class Rep1, class Period1, class Rep2, class Period2>
143  struct common_type<chrono::duration<Rep1, Period1>, chrono::duration<Rep2, Period2>>;
144
145template <class Clock, class Duration1, class Duration2>
146  struct common_type<chrono::time_point<Clock, Duration1>, chrono::time_point<Clock, Duration2>>;
147
148namespace chrono {
149
150// duration arithmetic
151template <class Rep1, class Period1, class Rep2, class Period2>
152  constexpr
153  typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2>>::type
154  operator+(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
155template <class Rep1, class Period1, class Rep2, class Period2>
156  constexpr
157  typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2>>::type
158  operator-(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
159template <class Rep1, class Period, class Rep2>
160  constexpr
161  duration<typename common_type<Rep1, Rep2>::type, Period>
162  operator*(const duration<Rep1, Period>& d, const Rep2& s);
163template <class Rep1, class Period, class Rep2>
164  constexpr
165  duration<typename common_type<Rep1, Rep2>::type, Period>
166  operator*(const Rep1& s, const duration<Rep2, Period>& d);
167template <class Rep1, class Period, class Rep2>
168  constexpr
169  duration<typename common_type<Rep1, Rep2>::type, Period>
170  operator/(const duration<Rep1, Period>& d, const Rep2& s);
171template <class Rep1, class Period1, class Rep2, class Period2>
172  constexpr
173  typename common_type<Rep1, Rep2>::type
174  operator/(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
175
176// duration comparisons
177template <class Rep1, class Period1, class Rep2, class Period2>
178   constexpr
179   bool operator==(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
180template <class Rep1, class Period1, class Rep2, class Period2>
181   constexpr
182   bool operator!=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
183template <class Rep1, class Period1, class Rep2, class Period2>
184   constexpr
185   bool operator< (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
186template <class Rep1, class Period1, class Rep2, class Period2>
187   constexpr
188   bool operator<=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
189template <class Rep1, class Period1, class Rep2, class Period2>
190   constexpr
191   bool operator> (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
192template <class Rep1, class Period1, class Rep2, class Period2>
193   constexpr
194   bool operator>=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
195
196// duration_cast
197template <class ToDuration, class Rep, class Period>
198  ToDuration duration_cast(const duration<Rep, Period>& d);
199
200template <class ToDuration, class Rep, class Period>
201    constexpr ToDuration floor(const duration<Rep, Period>& d);    // C++17
202template <class ToDuration, class Rep, class Period>
203    constexpr ToDuration ceil(const duration<Rep, Period>& d);     // C++17
204template <class ToDuration, class Rep, class Period>
205    constexpr ToDuration round(const duration<Rep, Period>& d);    // C++17
206
207// time_point arithmetic (all constexpr in C++14)
208template <class Clock, class Duration1, class Rep2, class Period2>
209  time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2>>::type>
210  operator+(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
211template <class Rep1, class Period1, class Clock, class Duration2>
212  time_point<Clock, typename common_type<duration<Rep1, Period1>, Duration2>::type>
213  operator+(const duration<Rep1, Period1>& lhs, const time_point<Clock, Duration2>& rhs);
214template <class Clock, class Duration1, class Rep2, class Period2>
215  time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2>>::type>
216  operator-(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
217template <class Clock, class Duration1, class Duration2>
218  typename common_type<Duration1, Duration2>::type
219  operator-(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
220
221// time_point comparisons (all constexpr in C++14)
222template <class Clock, class Duration1, class Duration2>
223   bool operator==(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
224template <class Clock, class Duration1, class Duration2>
225   bool operator!=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
226template <class Clock, class Duration1, class Duration2>
227   bool operator< (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
228template <class Clock, class Duration1, class Duration2>
229   bool operator<=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
230template <class Clock, class Duration1, class Duration2>
231   bool operator> (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
232template <class Clock, class Duration1, class Duration2>
233   bool operator>=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
234
235// time_point_cast (constexpr in C++14)
236
237template <class ToDuration, class Clock, class Duration>
238  time_point<Clock, ToDuration> time_point_cast(const time_point<Clock, Duration>& t);
239
240template <class ToDuration, class Clock, class Duration>
241    constexpr time_point<Clock, ToDuration>
242    floor(const time_point<Clock, Duration>& tp);                  // C++17
243
244template <class ToDuration, class Clock, class Duration>
245    constexpr time_point<Clock, ToDuration>
246    ceil(const time_point<Clock, Duration>& tp);                   // C++17
247
248template <class ToDuration, class Clock, class Duration>
249    constexpr time_point<Clock, ToDuration>
250    round(const time_point<Clock, Duration>& tp);                  // C++17
251
252template <class Rep, class Period>
253    constexpr duration<Rep, Period> abs(duration<Rep, Period> d);  // C++17
254// Clocks
255
256class system_clock
257{
258public:
259    typedef microseconds                     duration;
260    typedef duration::rep                    rep;
261    typedef duration::period                 period;
262    typedef chrono::time_point<system_clock> time_point;
263    static const bool is_steady =            false; // constexpr in C++14
264
265    static time_point now() noexcept;
266    static time_t     to_time_t  (const time_point& __t) noexcept;
267    static time_point from_time_t(time_t __t) noexcept;
268};
269
270class steady_clock
271{
272public:
273    typedef nanoseconds                                   duration;
274    typedef duration::rep                                 rep;
275    typedef duration::period                              period;
276    typedef chrono::time_point<steady_clock, duration>    time_point;
277    static const bool is_steady =                         true; // constexpr in C++14
278
279    static time_point now() noexcept;
280};
281
282typedef steady_clock high_resolution_clock;
283
284}  // chrono
285
286constexpr chrono::hours                                 operator "" h(unsigned long long); // C++14
287constexpr chrono::duration<unspecified , ratio<3600,1>> operator "" h(long double); // C++14
288constexpr chrono::minutes                               operator "" min(unsigned long long); // C++14
289constexpr chrono::duration<unspecified , ratio<60,1>>   operator "" min(long double); // C++14
290constexpr chrono::seconds                               operator "" s(unsigned long long); // C++14
291constexpr chrono::duration<unspecified >                operator "" s(long double); // C++14
292constexpr chrono::milliseconds                          operator "" ms(unsigned long long); // C++14
293constexpr chrono::duration<unspecified , milli>         operator "" ms(long double); // C++14
294constexpr chrono::microseconds                          operator "" us(unsigned long long); // C++14
295constexpr chrono::duration<unspecified , micro>         operator "" us(long double); // C++14
296constexpr chrono::nanoseconds                           operator "" ns(unsigned long long); // C++14
297constexpr chrono::duration<unspecified , nano>          operator "" ns(long double); // C++14
298
299}  // std
300*/
301
302#include <__config>
303#include <ctime>
304#include <type_traits>
305#include <ratio>
306#include <limits>
307
308#include <__undef_min_max>
309
310#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
311#pragma GCC system_header
312#endif
313
314_LIBCPP_BEGIN_NAMESPACE_STD
315
316namespace chrono
317{
318
319template <class _Rep, class _Period = ratio<1> > class _LIBCPP_TEMPLATE_VIS duration;
320
321template <class _Tp>
322struct __is_duration : false_type {};
323
324template <class _Rep, class _Period>
325struct __is_duration<duration<_Rep, _Period> > : true_type  {};
326
327template <class _Rep, class _Period>
328struct __is_duration<const duration<_Rep, _Period> > : true_type  {};
329
330template <class _Rep, class _Period>
331struct __is_duration<volatile duration<_Rep, _Period> > : true_type  {};
332
333template <class _Rep, class _Period>
334struct __is_duration<const volatile duration<_Rep, _Period> > : true_type  {};
335
336} // chrono
337
338template <class _Rep1, class _Period1, class _Rep2, class _Period2>
339struct _LIBCPP_TEMPLATE_VIS common_type<chrono::duration<_Rep1, _Period1>,
340                                         chrono::duration<_Rep2, _Period2> >
341{
342    typedef chrono::duration<typename common_type<_Rep1, _Rep2>::type,
343                             typename __ratio_gcd<_Period1, _Period2>::type> type;
344};
345
346namespace chrono {
347
348// duration_cast
349
350template <class _FromDuration, class _ToDuration,
351          class _Period = typename ratio_divide<typename _FromDuration::period, typename _ToDuration::period>::type,
352          bool = _Period::num == 1,
353          bool = _Period::den == 1>
354struct __duration_cast;
355
356template <class _FromDuration, class _ToDuration, class _Period>
357struct __duration_cast<_FromDuration, _ToDuration, _Period, true, true>
358{
359    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
360    _ToDuration operator()(const _FromDuration& __fd) const
361    {
362        return _ToDuration(static_cast<typename _ToDuration::rep>(__fd.count()));
363    }
364};
365
366template <class _FromDuration, class _ToDuration, class _Period>
367struct __duration_cast<_FromDuration, _ToDuration, _Period, true, false>
368{
369    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
370    _ToDuration operator()(const _FromDuration& __fd) const
371    {
372        typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
373        return _ToDuration(static_cast<typename _ToDuration::rep>(
374                           static_cast<_Ct>(__fd.count()) / static_cast<_Ct>(_Period::den)));
375    }
376};
377
378template <class _FromDuration, class _ToDuration, class _Period>
379struct __duration_cast<_FromDuration, _ToDuration, _Period, false, true>
380{
381    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
382    _ToDuration operator()(const _FromDuration& __fd) const
383    {
384        typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
385        return _ToDuration(static_cast<typename _ToDuration::rep>(
386                           static_cast<_Ct>(__fd.count()) * static_cast<_Ct>(_Period::num)));
387    }
388};
389
390template <class _FromDuration, class _ToDuration, class _Period>
391struct __duration_cast<_FromDuration, _ToDuration, _Period, false, false>
392{
393    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
394    _ToDuration operator()(const _FromDuration& __fd) const
395    {
396        typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
397        return _ToDuration(static_cast<typename _ToDuration::rep>(
398                           static_cast<_Ct>(__fd.count()) * static_cast<_Ct>(_Period::num)
399                                                          / static_cast<_Ct>(_Period::den)));
400    }
401};
402
403template <class _ToDuration, class _Rep, class _Period>
404inline _LIBCPP_INLINE_VISIBILITY
405_LIBCPP_CONSTEXPR
406typename enable_if
407<
408    __is_duration<_ToDuration>::value,
409    _ToDuration
410>::type
411duration_cast(const duration<_Rep, _Period>& __fd)
412{
413    return __duration_cast<duration<_Rep, _Period>, _ToDuration>()(__fd);
414}
415
416template <class _Rep>
417struct _LIBCPP_TEMPLATE_VIS treat_as_floating_point : is_floating_point<_Rep> {};
418
419#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
420template <class _Rep> _LIBCPP_CONSTEXPR bool treat_as_floating_point_v
421    = treat_as_floating_point<_Rep>::value;
422#endif
423
424template <class _Rep>
425struct _LIBCPP_TEMPLATE_VIS duration_values
426{
427public:
428    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR _Rep zero() {return _Rep(0);}
429    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR _Rep max()  {return numeric_limits<_Rep>::max();}
430    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR _Rep min()  {return numeric_limits<_Rep>::lowest();}
431};
432
433#if _LIBCPP_STD_VER > 14
434template <class _ToDuration, class _Rep, class _Period>
435inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
436typename enable_if
437<
438    __is_duration<_ToDuration>::value,
439    _ToDuration
440>::type
441floor(const duration<_Rep, _Period>& __d)
442{
443    _ToDuration __t = duration_cast<_ToDuration>(__d);
444    if (__t > __d)
445        __t = __t - _ToDuration{1};
446    return __t;
447}
448
449template <class _ToDuration, class _Rep, class _Period>
450inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
451typename enable_if
452<
453    __is_duration<_ToDuration>::value,
454    _ToDuration
455>::type
456ceil(const duration<_Rep, _Period>& __d)
457{
458    _ToDuration __t = duration_cast<_ToDuration>(__d);
459    if (__t < __d)
460        __t = __t + _ToDuration{1};
461    return __t;
462}
463
464template <class _ToDuration, class _Rep, class _Period>
465inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
466typename enable_if
467<
468    __is_duration<_ToDuration>::value,
469    _ToDuration
470>::type
471round(const duration<_Rep, _Period>& __d)
472{
473    _ToDuration __lower = floor<_ToDuration>(__d);
474    _ToDuration __upper = __lower + _ToDuration{1};
475    auto __lowerDiff = __d - __lower;
476    auto __upperDiff = __upper - __d;
477    if (__lowerDiff < __upperDiff)
478        return __lower;
479    if (__lowerDiff > __upperDiff)
480        return __upper;
481    return __lower.count() & 1 ? __upper : __lower;
482}
483#endif
484
485// duration
486
487template <class _Rep, class _Period>
488class _LIBCPP_TEMPLATE_VIS duration
489{
490    static_assert(!__is_duration<_Rep>::value, "A duration representation can not be a duration");
491    static_assert(__is_ratio<_Period>::value, "Second template parameter of duration must be a std::ratio");
492    static_assert(_Period::num > 0, "duration period must be positive");
493
494    template <class _R1, class _R2>
495    struct __no_overflow
496    {
497    private:
498        static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
499        static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
500        static const intmax_t __n1 = _R1::num / __gcd_n1_n2;
501        static const intmax_t __d1 = _R1::den / __gcd_d1_d2;
502        static const intmax_t __n2 = _R2::num / __gcd_n1_n2;
503        static const intmax_t __d2 = _R2::den / __gcd_d1_d2;
504        static const intmax_t max = -((intmax_t(1) << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1);
505
506        template <intmax_t _Xp, intmax_t _Yp, bool __overflow>
507        struct __mul    // __overflow == false
508        {
509            static const intmax_t value = _Xp * _Yp;
510        };
511
512        template <intmax_t _Xp, intmax_t _Yp>
513        struct __mul<_Xp, _Yp, true>
514        {
515            static const intmax_t value = 1;
516        };
517
518    public:
519        static const bool value = (__n1 <= max / __d2) && (__n2 <= max / __d1);
520        typedef ratio<__mul<__n1, __d2, !value>::value,
521                      __mul<__n2, __d1, !value>::value> type;
522    };
523
524public:
525    typedef _Rep rep;
526    typedef _Period period;
527private:
528    rep __rep_;
529public:
530
531    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
532#ifndef _LIBCPP_CXX03_LANG
533        duration() = default;
534#else
535        duration() {}
536#endif
537
538    template <class _Rep2>
539        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
540        explicit duration(const _Rep2& __r,
541            typename enable_if
542            <
543               is_convertible<_Rep2, rep>::value &&
544               (treat_as_floating_point<rep>::value ||
545               !treat_as_floating_point<_Rep2>::value)
546            >::type* = 0)
547                : __rep_(__r) {}
548
549    // conversions
550    template <class _Rep2, class _Period2>
551        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
552        duration(const duration<_Rep2, _Period2>& __d,
553            typename enable_if
554            <
555                __no_overflow<_Period2, period>::value && (
556                treat_as_floating_point<rep>::value ||
557                (__no_overflow<_Period2, period>::type::den == 1 &&
558                 !treat_as_floating_point<_Rep2>::value))
559            >::type* = 0)
560                : __rep_(_VSTD::chrono::duration_cast<duration>(__d).count()) {}
561
562    // observer
563
564    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR rep count() const {return __rep_;}
565
566    // arithmetic
567
568    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR duration  operator+() const {return *this;}
569    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR duration  operator-() const {return duration(-__rep_);}
570    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator++()      {++__rep_; return *this;}
571    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration  operator++(int)   {return duration(__rep_++);}
572    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator--()      {--__rep_; return *this;}
573    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration  operator--(int)   {return duration(__rep_--);}
574
575    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator+=(const duration& __d) {__rep_ += __d.count(); return *this;}
576    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator-=(const duration& __d) {__rep_ -= __d.count(); return *this;}
577
578    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator*=(const rep& rhs) {__rep_ *= rhs; return *this;}
579    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator/=(const rep& rhs) {__rep_ /= rhs; return *this;}
580    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator%=(const rep& rhs) {__rep_ %= rhs; return *this;}
581    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator%=(const duration& rhs) {__rep_ %= rhs.count(); return *this;}
582
583    // special values
584
585    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR duration zero() {return duration(duration_values<rep>::zero());}
586    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR duration min()  {return duration(duration_values<rep>::min());}
587    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR duration max()  {return duration(duration_values<rep>::max());}
588};
589
590typedef duration<long long,         nano> nanoseconds;
591typedef duration<long long,        micro> microseconds;
592typedef duration<long long,        milli> milliseconds;
593typedef duration<long long              > seconds;
594typedef duration<     long, ratio<  60> > minutes;
595typedef duration<     long, ratio<3600> > hours;
596
597// Duration ==
598
599template <class _LhsDuration, class _RhsDuration>
600struct __duration_eq
601{
602    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
603    bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs) const
604        {
605            typedef typename common_type<_LhsDuration, _RhsDuration>::type _Ct;
606            return _Ct(__lhs).count() == _Ct(__rhs).count();
607        }
608};
609
610template <class _LhsDuration>
611struct __duration_eq<_LhsDuration, _LhsDuration>
612{
613    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
614    bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs) const
615        {return __lhs.count() == __rhs.count();}
616};
617
618template <class _Rep1, class _Period1, class _Rep2, class _Period2>
619inline _LIBCPP_INLINE_VISIBILITY
620_LIBCPP_CONSTEXPR
621bool
622operator==(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
623{
624    return __duration_eq<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >()(__lhs, __rhs);
625}
626
627// Duration !=
628
629template <class _Rep1, class _Period1, class _Rep2, class _Period2>
630inline _LIBCPP_INLINE_VISIBILITY
631_LIBCPP_CONSTEXPR
632bool
633operator!=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
634{
635    return !(__lhs == __rhs);
636}
637
638// Duration <
639
640template <class _LhsDuration, class _RhsDuration>
641struct __duration_lt
642{
643    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
644    bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs) const
645        {
646            typedef typename common_type<_LhsDuration, _RhsDuration>::type _Ct;
647            return _Ct(__lhs).count() < _Ct(__rhs).count();
648        }
649};
650
651template <class _LhsDuration>
652struct __duration_lt<_LhsDuration, _LhsDuration>
653{
654    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
655    bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs) const
656        {return __lhs.count() < __rhs.count();}
657};
658
659template <class _Rep1, class _Period1, class _Rep2, class _Period2>
660inline _LIBCPP_INLINE_VISIBILITY
661_LIBCPP_CONSTEXPR
662bool
663operator< (const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
664{
665    return __duration_lt<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >()(__lhs, __rhs);
666}
667
668// Duration >
669
670template <class _Rep1, class _Period1, class _Rep2, class _Period2>
671inline _LIBCPP_INLINE_VISIBILITY
672_LIBCPP_CONSTEXPR
673bool
674operator> (const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
675{
676    return __rhs < __lhs;
677}
678
679// Duration <=
680
681template <class _Rep1, class _Period1, class _Rep2, class _Period2>
682inline _LIBCPP_INLINE_VISIBILITY
683_LIBCPP_CONSTEXPR
684bool
685operator<=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
686{
687    return !(__rhs < __lhs);
688}
689
690// Duration >=
691
692template <class _Rep1, class _Period1, class _Rep2, class _Period2>
693inline _LIBCPP_INLINE_VISIBILITY
694_LIBCPP_CONSTEXPR
695bool
696operator>=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
697{
698    return !(__lhs < __rhs);
699}
700
701// Duration +
702
703template <class _Rep1, class _Period1, class _Rep2, class _Period2>
704inline _LIBCPP_INLINE_VISIBILITY
705_LIBCPP_CONSTEXPR
706typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
707operator+(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
708{
709    typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
710    return _Cd(_Cd(__lhs).count() + _Cd(__rhs).count());
711}
712
713// Duration -
714
715template <class _Rep1, class _Period1, class _Rep2, class _Period2>
716inline _LIBCPP_INLINE_VISIBILITY
717_LIBCPP_CONSTEXPR
718typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
719operator-(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
720{
721    typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
722    return _Cd(_Cd(__lhs).count() - _Cd(__rhs).count());
723}
724
725// Duration *
726
727template <class _Rep1, class _Period, class _Rep2>
728inline _LIBCPP_INLINE_VISIBILITY
729_LIBCPP_CONSTEXPR
730typename enable_if
731<
732    is_convertible<_Rep2, typename common_type<_Rep1, _Rep2>::type>::value,
733    duration<typename common_type<_Rep1, _Rep2>::type, _Period>
734>::type
735operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
736{
737    typedef typename common_type<_Rep1, _Rep2>::type _Cr;
738    typedef duration<_Cr, _Period> _Cd;
739    return _Cd(_Cd(__d).count() * static_cast<_Cr>(__s));
740}
741
742template <class _Rep1, class _Period, class _Rep2>
743inline _LIBCPP_INLINE_VISIBILITY
744_LIBCPP_CONSTEXPR
745typename enable_if
746<
747    is_convertible<_Rep1, typename common_type<_Rep1, _Rep2>::type>::value,
748    duration<typename common_type<_Rep1, _Rep2>::type, _Period>
749>::type
750operator*(const _Rep1& __s, const duration<_Rep2, _Period>& __d)
751{
752    return __d * __s;
753}
754
755// Duration /
756
757template <class _Duration, class _Rep, bool = __is_duration<_Rep>::value>
758struct __duration_divide_result
759{
760};
761
762template <class _Duration, class _Rep2,
763    bool = is_convertible<_Rep2,
764                          typename common_type<typename _Duration::rep, _Rep2>::type>::value>
765struct __duration_divide_imp
766{
767};
768
769template <class _Rep1, class _Period, class _Rep2>
770struct __duration_divide_imp<duration<_Rep1, _Period>, _Rep2, true>
771{
772    typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period> type;
773};
774
775template <class _Rep1, class _Period, class _Rep2>
776struct __duration_divide_result<duration<_Rep1, _Period>, _Rep2, false>
777    : __duration_divide_imp<duration<_Rep1, _Period>, _Rep2>
778{
779};
780
781template <class _Rep1, class _Period, class _Rep2>
782inline _LIBCPP_INLINE_VISIBILITY
783_LIBCPP_CONSTEXPR
784typename __duration_divide_result<duration<_Rep1, _Period>, _Rep2>::type
785operator/(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
786{
787    typedef typename common_type<_Rep1, _Rep2>::type _Cr;
788    typedef duration<_Cr, _Period> _Cd;
789    return _Cd(_Cd(__d).count() / static_cast<_Cr>(__s));
790}
791
792template <class _Rep1, class _Period1, class _Rep2, class _Period2>
793inline _LIBCPP_INLINE_VISIBILITY
794_LIBCPP_CONSTEXPR
795typename common_type<_Rep1, _Rep2>::type
796operator/(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
797{
798    typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Ct;
799    return _Ct(__lhs).count() / _Ct(__rhs).count();
800}
801
802// Duration %
803
804template <class _Rep1, class _Period, class _Rep2>
805inline _LIBCPP_INLINE_VISIBILITY
806_LIBCPP_CONSTEXPR
807typename __duration_divide_result<duration<_Rep1, _Period>, _Rep2>::type
808operator%(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
809{
810    typedef typename common_type<_Rep1, _Rep2>::type _Cr;
811    typedef duration<_Cr, _Period> _Cd;
812    return _Cd(_Cd(__d).count() % static_cast<_Cr>(__s));
813}
814
815template <class _Rep1, class _Period1, class _Rep2, class _Period2>
816inline _LIBCPP_INLINE_VISIBILITY
817_LIBCPP_CONSTEXPR
818typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
819operator%(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
820{
821    typedef typename common_type<_Rep1, _Rep2>::type _Cr;
822    typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
823    return _Cd(static_cast<_Cr>(_Cd(__lhs).count()) % static_cast<_Cr>(_Cd(__rhs).count()));
824}
825
826//////////////////////////////////////////////////////////
827///////////////////// time_point /////////////////////////
828//////////////////////////////////////////////////////////
829
830template <class _Clock, class _Duration = typename _Clock::duration>
831class _LIBCPP_TEMPLATE_VIS time_point
832{
833    static_assert(__is_duration<_Duration>::value,
834                  "Second template parameter of time_point must be a std::chrono::duration");
835public:
836    typedef _Clock                    clock;
837    typedef _Duration                 duration;
838    typedef typename duration::rep    rep;
839    typedef typename duration::period period;
840private:
841    duration __d_;
842
843public:
844    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 time_point() : __d_(duration::zero()) {}
845    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 explicit time_point(const duration& __d) : __d_(__d) {}
846
847    // conversions
848    template <class _Duration2>
849    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
850    time_point(const time_point<clock, _Duration2>& t,
851        typename enable_if
852        <
853            is_convertible<_Duration2, duration>::value
854        >::type* = 0)
855            : __d_(t.time_since_epoch()) {}
856
857    // observer
858
859    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 duration time_since_epoch() const {return __d_;}
860
861    // arithmetic
862
863    _LIBCPP_INLINE_VISIBILITY time_point& operator+=(const duration& __d) {__d_ += __d; return *this;}
864    _LIBCPP_INLINE_VISIBILITY time_point& operator-=(const duration& __d) {__d_ -= __d; return *this;}
865
866    // special values
867
868    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR time_point min() {return time_point(duration::min());}
869    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR time_point max() {return time_point(duration::max());}
870};
871
872} // chrono
873
874template <class _Clock, class _Duration1, class _Duration2>
875struct _LIBCPP_TEMPLATE_VIS common_type<chrono::time_point<_Clock, _Duration1>,
876                                         chrono::time_point<_Clock, _Duration2> >
877{
878    typedef chrono::time_point<_Clock, typename common_type<_Duration1, _Duration2>::type> type;
879};
880
881namespace chrono {
882
883template <class _ToDuration, class _Clock, class _Duration>
884inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
885time_point<_Clock, _ToDuration>
886time_point_cast(const time_point<_Clock, _Duration>& __t)
887{
888    return time_point<_Clock, _ToDuration>(_VSTD::chrono::duration_cast<_ToDuration>(__t.time_since_epoch()));
889}
890
891#if _LIBCPP_STD_VER > 14
892template <class _ToDuration, class _Clock, class _Duration>
893inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
894typename enable_if
895<
896    __is_duration<_ToDuration>::value,
897    time_point<_Clock, _ToDuration>
898>::type
899floor(const time_point<_Clock, _Duration>& __t)
900{
901    return time_point<_Clock, _ToDuration>{floor<_ToDuration>(__t.time_since_epoch())};
902}
903
904template <class _ToDuration, class _Clock, class _Duration>
905inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
906typename enable_if
907<
908    __is_duration<_ToDuration>::value,
909    time_point<_Clock, _ToDuration>
910>::type
911ceil(const time_point<_Clock, _Duration>& __t)
912{
913    return time_point<_Clock, _ToDuration>{ceil<_ToDuration>(__t.time_since_epoch())};
914}
915
916template <class _ToDuration, class _Clock, class _Duration>
917inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
918typename enable_if
919<
920    __is_duration<_ToDuration>::value,
921    time_point<_Clock, _ToDuration>
922>::type
923round(const time_point<_Clock, _Duration>& __t)
924{
925    return time_point<_Clock, _ToDuration>{round<_ToDuration>(__t.time_since_epoch())};
926}
927
928template <class _Rep, class _Period>
929inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
930typename enable_if
931<
932    numeric_limits<_Rep>::is_signed,
933    duration<_Rep, _Period>
934>::type
935abs(duration<_Rep, _Period> __d)
936{
937    return __d >= __d.zero() ? __d : -__d;
938}
939#endif
940
941// time_point ==
942
943template <class _Clock, class _Duration1, class _Duration2>
944inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
945bool
946operator==(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
947{
948    return __lhs.time_since_epoch() == __rhs.time_since_epoch();
949}
950
951// time_point !=
952
953template <class _Clock, class _Duration1, class _Duration2>
954inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
955bool
956operator!=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
957{
958    return !(__lhs == __rhs);
959}
960
961// time_point <
962
963template <class _Clock, class _Duration1, class _Duration2>
964inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
965bool
966operator<(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
967{
968    return __lhs.time_since_epoch() < __rhs.time_since_epoch();
969}
970
971// time_point >
972
973template <class _Clock, class _Duration1, class _Duration2>
974inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
975bool
976operator>(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
977{
978    return __rhs < __lhs;
979}
980
981// time_point <=
982
983template <class _Clock, class _Duration1, class _Duration2>
984inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
985bool
986operator<=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
987{
988    return !(__rhs < __lhs);
989}
990
991// time_point >=
992
993template <class _Clock, class _Duration1, class _Duration2>
994inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
995bool
996operator>=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
997{
998    return !(__lhs < __rhs);
999}
1000
1001// time_point operator+(time_point x, duration y);
1002
1003template <class _Clock, class _Duration1, class _Rep2, class _Period2>
1004inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1005time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type>
1006operator+(const time_point<_Clock, _Duration1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1007{
1008    typedef time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type> _Tr;
1009    return _Tr (__lhs.time_since_epoch() + __rhs);
1010}
1011
1012// time_point operator+(duration x, time_point y);
1013
1014template <class _Rep1, class _Period1, class _Clock, class _Duration2>
1015inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1016time_point<_Clock, typename common_type<duration<_Rep1, _Period1>, _Duration2>::type>
1017operator+(const duration<_Rep1, _Period1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1018{
1019    return __rhs + __lhs;
1020}
1021
1022// time_point operator-(time_point x, duration y);
1023
1024template <class _Clock, class _Duration1, class _Rep2, class _Period2>
1025inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1026time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type>
1027operator-(const time_point<_Clock, _Duration1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1028{
1029    typedef time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type> _Ret;
1030    return _Ret(__lhs.time_since_epoch() -__rhs);
1031}
1032
1033// duration operator-(time_point x, time_point y);
1034
1035template <class _Clock, class _Duration1, class _Duration2>
1036inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1037typename common_type<_Duration1, _Duration2>::type
1038operator-(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1039{
1040    return __lhs.time_since_epoch() - __rhs.time_since_epoch();
1041}
1042
1043//////////////////////////////////////////////////////////
1044/////////////////////// clocks ///////////////////////////
1045//////////////////////////////////////////////////////////
1046
1047class _LIBCPP_TYPE_VIS system_clock
1048{
1049public:
1050    typedef microseconds                     duration;
1051    typedef duration::rep                    rep;
1052    typedef duration::period                 period;
1053    typedef chrono::time_point<system_clock> time_point;
1054    static _LIBCPP_CONSTEXPR_AFTER_CXX11 const bool is_steady = false;
1055
1056    static time_point now() _NOEXCEPT;
1057    static time_t     to_time_t  (const time_point& __t) _NOEXCEPT;
1058    static time_point from_time_t(time_t __t) _NOEXCEPT;
1059};
1060
1061#ifndef _LIBCPP_HAS_NO_MONOTONIC_CLOCK
1062class _LIBCPP_TYPE_VIS steady_clock
1063{
1064public:
1065    typedef nanoseconds                                   duration;
1066    typedef duration::rep                                 rep;
1067    typedef duration::period                              period;
1068    typedef chrono::time_point<steady_clock, duration>    time_point;
1069    static _LIBCPP_CONSTEXPR_AFTER_CXX11 const bool is_steady = true;
1070
1071    static time_point now() _NOEXCEPT;
1072};
1073
1074typedef steady_clock high_resolution_clock;
1075#else
1076typedef system_clock high_resolution_clock;
1077#endif
1078
1079} // chrono
1080
1081#if _LIBCPP_STD_VER > 11
1082// Suffixes for duration literals [time.duration.literals]
1083inline namespace literals
1084{
1085  inline namespace chrono_literals
1086  {
1087
1088    constexpr chrono::hours operator"" h(unsigned long long __h)
1089    {
1090        return chrono::hours(static_cast<chrono::hours::rep>(__h));
1091    }
1092
1093    constexpr chrono::duration<long double, ratio<3600,1>> operator"" h(long double __h)
1094    {
1095        return chrono::duration<long double, ratio<3600,1>>(__h);
1096    }
1097
1098
1099    constexpr chrono::minutes operator"" min(unsigned long long __m)
1100    {
1101        return chrono::minutes(static_cast<chrono::minutes::rep>(__m));
1102    }
1103
1104    constexpr chrono::duration<long double, ratio<60,1>> operator"" min(long double __m)
1105    {
1106        return chrono::duration<long double, ratio<60,1>> (__m);
1107    }
1108
1109
1110    constexpr chrono::seconds operator"" s(unsigned long long __s)
1111    {
1112        return chrono::seconds(static_cast<chrono::seconds::rep>(__s));
1113    }
1114
1115    constexpr chrono::duration<long double> operator"" s(long double __s)
1116    {
1117        return chrono::duration<long double> (__s);
1118    }
1119
1120
1121    constexpr chrono::milliseconds operator"" ms(unsigned long long __ms)
1122    {
1123        return chrono::milliseconds(static_cast<chrono::milliseconds::rep>(__ms));
1124    }
1125
1126    constexpr chrono::duration<long double, milli> operator"" ms(long double __ms)
1127    {
1128        return chrono::duration<long double, milli>(__ms);
1129    }
1130
1131
1132    constexpr chrono::microseconds operator"" us(unsigned long long __us)
1133    {
1134        return chrono::microseconds(static_cast<chrono::microseconds::rep>(__us));
1135    }
1136
1137    constexpr chrono::duration<long double, micro> operator"" us(long double __us)
1138    {
1139        return chrono::duration<long double, micro> (__us);
1140    }
1141
1142
1143    constexpr chrono::nanoseconds operator"" ns(unsigned long long __ns)
1144    {
1145        return chrono::nanoseconds(static_cast<chrono::nanoseconds::rep>(__ns));
1146    }
1147
1148    constexpr chrono::duration<long double, nano> operator"" ns(long double __ns)
1149    {
1150        return chrono::duration<long double, nano> (__ns);
1151    }
1152
1153}}
1154
1155namespace chrono { // hoist the literals into namespace std::chrono
1156   using namespace literals::chrono_literals;
1157}
1158
1159#endif
1160
1161_LIBCPP_END_NAMESPACE_STD
1162
1163#endif  // _LIBCPP_CHRONO
1164