With changes r16-2063-g8ad5968a8dcb47 the _M_a_A, _M_b_B and _M_p functions are called only if the locale is equal to the locale::classic(), for which the behavior is know. This patch changes they implementation, so instead of reffering to __timepunct facet members, they use hardcoded list of English weekday, months names. Only one list is needed, as in case of locale::classic() abbreviated name corresponds to first tree letters of the full name.
For _M_p, _M_r we use a new _M_fill_ampm helper, that fills provided buffer with "AM"/"PM" depending on the hours value. In _M_S we no longer guard querying of numpuct facet, with check that requires potentially equally expensive construction of locale::classic. We also mark localized path as unlikely. The _M_locale method is no longer used in __formatter_chrono, and thus was moved to __formatter_duration. PR libstdc++/110739 libstdc++-v3/ChangeLog: * include/bits/chrono_io.h (__formatter_chrono::_S_weekdays) (__formatter_chrono::_S_months, __formatter_chrono::_S_fill_ampm): Define. (__formatter_chrono::_M_format_to): Do not pass context parameter to functions listed below. (__formatter_chrono::_M_a_A, __formatter_chrono::_M_b_B): Implement using harcoded list of names, and remove format context parameter. (__formatter_chrono::_M_p, __formatter_chrono::_M_r): Implement using _S_fill_ampm. (__formatter_chrono::_M_c): Removed format context parameter. (__formatter_chrono::_M_subsecs): Call __ctx.locale() directly, instead of _M_locale and do not compare with locale::classic(). Add [[unlikely]] attributes. (__formatter_chrono::_M_locale): Move to __formatter_duration. (__formatter_duration::_M_locale): Moved from __formatter_chrono. --- Changing the approach, as we _M_a_A, _M_b_B and _M_p functions are no longer called for locale other than classic(). Testing on x86_64-linux. Test for std/time/format* already passed. OK for trunk, when all test passes. libstdc++-v3/include/bits/chrono_io.h | 154 +++++++++++++++----------- 1 file changed, 87 insertions(+), 67 deletions(-) diff --git a/libstdc++-v3/include/bits/chrono_io.h b/libstdc++-v3/include/bits/chrono_io.h index 75ee7e818b2..fe3c9126749 100644 --- a/libstdc++-v3/include/bits/chrono_io.h +++ b/libstdc++-v3/include/bits/chrono_io.h @@ -881,16 +881,32 @@ namespace __format _S_empty_fs() { return _Runtime_format_string<_CharT>(_S_empty_spec); } - // Return the formatting locale. - template<typename _FormatContext> - std::locale - _M_locale(_FormatContext& __fc) const - { - if (!_M_spec._M_localized) - return std::locale::classic(); - else - return __fc.locale(); - } + static constexpr const _CharT* _S_weekdays[] + { + _GLIBCXX_WIDEN("Sunday"), + _GLIBCXX_WIDEN("Monday"), + _GLIBCXX_WIDEN("Tuesday"), + _GLIBCXX_WIDEN("Wednesday"), + _GLIBCXX_WIDEN("Thursday"), + _GLIBCXX_WIDEN("Friday"), + _GLIBCXX_WIDEN("Saturday"), + }; + + static constexpr const _CharT* _S_months[] + { + _GLIBCXX_WIDEN("January"), + _GLIBCXX_WIDEN("February"), + _GLIBCXX_WIDEN("March"), + _GLIBCXX_WIDEN("April"), + _GLIBCXX_WIDEN("May"), + _GLIBCXX_WIDEN("June"), + _GLIBCXX_WIDEN("July"), + _GLIBCXX_WIDEN("August"), + _GLIBCXX_WIDEN("September"), + _GLIBCXX_WIDEN("October"), + _GLIBCXX_WIDEN("November"), + _GLIBCXX_WIDEN("December"), + }; private: template<typename _OutIter> @@ -1051,15 +1067,15 @@ namespace __format break; case 'a': case 'A': - __out = _M_a_A(__t._M_weekday, std::move(__out), __fc, __c == 'A'); + __out = _M_a_A(__t._M_weekday, std::move(__out), __c == 'A'); break; case 'b': case 'h': case 'B': - __out = _M_b_B(__t._M_month, std::move(__out), __fc, __c == 'B'); + __out = _M_b_B(__t._M_month, std::move(__out), __c == 'B'); break; case 'c': - __out = _M_c(__t, std::move(__out), __fc); + __out = _M_c(__t, std::move(__out)); break; case 'C': case 'y': @@ -1095,7 +1111,7 @@ namespace __format __out = _M_M(__t._M_minutes, __print_sign()); break; case 'p': - __out = _M_p(__t._M_hours, std::move(__out), __fc); + __out = _M_p(__t._M_hours, std::move(__out)); break; case 'q': __out = _M_q(__t._M_unit_suffix, std::move(__out)); @@ -1104,7 +1120,7 @@ namespace __format __out = _M_Q(__t, __print_sign(), __fc); break; case 'r': - __out = _M_r(__t, __print_sign(), __fc); + __out = _M_r(__t, __print_sign()); break; case 'R': case 'X': @@ -1183,10 +1199,9 @@ namespace __format return std::move(__out); } - template<typename _OutIter, typename _FormatContext> + template<typename _OutIter> _OutIter - _M_a_A(chrono::weekday __wd, _OutIter __out, - _FormatContext& __ctx, bool __full) const + _M_a_A(chrono::weekday __wd, _OutIter __out, bool __full) const { // %a Locale's abbreviated weekday name. // %A Locale's full weekday name. @@ -1199,21 +1214,15 @@ namespace __format __string_view(_GLIBCXX_WIDEN(" is not a valid weekday"))); } - locale __loc = _M_locale(__ctx); - const auto& __tp = use_facet<__timepunct<_CharT>>(__loc); - const _CharT* __days[7]; - if (__full) - __tp._M_days(__days); - else - __tp._M_days_abbreviated(__days); - __string_view __str(__days[__wd.c_encoding()]); - return _M_write(std::move(__out), __loc, __str); + __string_view __str = _S_weekdays[__wd.c_encoding()]; + if (!__full) + __str = __str.substr(0, 3); + return __format::__write(std::move(__out), __str); } - template<typename _OutIter, typename _FormatContext> + template<typename _OutIter> _OutIter - _M_b_B(chrono::month __m, _OutIter __out, - _FormatContext& __ctx, bool __full) const + _M_b_B(chrono::month __m, _OutIter __out, bool __full) const { // %b Locale's abbreviated month name. // %B Locale's full month name. @@ -1226,28 +1235,22 @@ namespace __format __string_view(_GLIBCXX_WIDEN(" is not a valid month"))); } - locale __loc = _M_locale(__ctx); - const auto& __tp = use_facet<__timepunct<_CharT>>(__loc); - const _CharT* __months[12]; - if (__full) - __tp._M_months(__months); - else - __tp._M_months_abbreviated(__months); - __string_view __str(__months[(unsigned)__m - 1]); - return _M_write(std::move(__out), __loc, __str); + __string_view __str = _S_months[(unsigned)__m - 1]; + if (!__full) + __str = __str.substr(0, 3); + return __format::__write(std::move(__out), __str); } - template<typename _OutIter, typename _FormatContext> + template<typename _OutIter> _OutIter - _M_c(const _ChronoData<_CharT>& __t, _OutIter __out, - _FormatContext& __ctx) const + _M_c(const _ChronoData<_CharT>& __t, _OutIter __out) const { // %c Locale's date and time representation, for C-locale: %a %b %e %T %Y // %Ec Locale's alternate date and time representation, for C-locale same as above - __out = _M_a_A(__t._M_weekday, std::move(__out), __ctx, false); + __out = _M_a_A(__t._M_weekday, std::move(__out), false); *__out = _S_space; - __out = _M_b_B(__t._M_month, std::move(++__out), __ctx, false); + __out = _M_b_B(__t._M_month, std::move(++__out), false); *__out = _S_space; __out = _M_d_e(__t._M_day, std::move(++__out), 'e'); *__out = _S_space; @@ -1489,20 +1492,15 @@ namespace __format return __format::__write(std::move(__out), _S_two_digits(__i)); } - template<typename _OutIter, typename _FormatContext> + template<typename _OutIter> _OutIter - _M_p(chrono::hours __h, _OutIter __out, _FormatContext& __ctx) const + _M_p(chrono::hours __h, _OutIter __out) const { // %p The locale's equivalent of the AM/PM designations. - auto __hi = __h.count(); - if (__hi >= 24) [[unlikely]] - __hi %= 24; - - locale __loc = _M_locale(__ctx); - const auto& __tp = use_facet<__timepunct<_CharT>>(__loc); - const _CharT* __ampm[2]; - __tp._M_am_pm(__ampm); - return _M_write(std::move(__out), __loc, __ampm[__hi >= 12]); + + _CharT __buf[2]; + _S_fill_ampm(__buf, __h); + return __format::__write(std::move(__out), __string_view(__buf, 2)); } template<typename _OutIter> @@ -1522,27 +1520,25 @@ namespace __format return std::vformat_to(std::move(__out), _S_empty_spec, __t._M_ereps); } - template<typename _OutIter, typename _FormatContext> + template<typename _OutIter> _OutIter - _M_r(const _ChronoData<_CharT>& __t, _OutIter __out, - _FormatContext& __ctx) const + _M_r(const _ChronoData<_CharT>& __t, _OutIter __out) const { // %r Locale's 12-hour clock time, for C-locale: %I:%M:%S %p auto __hi = __t._M_hours.count() % 12; if (__hi == 0) __hi = 12; - _CharT __buf[9]; + _CharT __buf[11]; __buf[2] = _S_colon; __buf[5] = _S_colon; __buf[8] = _S_space; _S_fill_two_digits(__buf, __hi); _S_fill_two_digits(__buf + 3, __t._M_minutes.count()); _S_fill_two_digits(__buf + 6, __t._M_seconds.count()); + _S_fill_ampm(__buf + 9, __t._M_hours); - __string_view __sv(__buf, 9); - __out = __format::__write(std::move(__out), __sv); - return _M_p(__t._M_hours, std::move(__out), __ctx); + return __format::__write(std::move(__out), __string_view(__buf, 11)); } template<typename _OutIter> @@ -1606,9 +1602,9 @@ namespace __format return __out; _CharT __dot = _S_dot; - if (_M_spec._M_localized) - if (auto __loc = __ctx.locale(); __loc != locale::classic()) + if (_M_spec._M_localized) [[unlikely]] { + auto __loc = __ctx.locale(); const auto& __np = use_facet<numpunct<_CharT>>(__loc); __dot = __np.decimal_point(); } @@ -1618,8 +1614,8 @@ namespace __format if (_M_spec._M_floating_point_rep) { _Str_sink<_CharT> __sink; - if (_M_spec._M_localized && _M_spec._M_custom_rep) - std::vformat_to(__sink.out(), _M_locale(__ctx), + if (_M_spec._M_localized && _M_spec._M_custom_rep) [[unlikely]] + std::vformat_to(__sink.out(), __ctx.locale(), _GLIBCXX_WIDEN("{1:0.{2}Lf}"), __t._M_ereps); else std::vformat_to(__sink.out(), @@ -1778,6 +1774,20 @@ namespace __format __buf[1] = __sv[1]; } + // Fills __buf[0] and __buf[1] with "AM", "PM" depending on __h. + [[__gnu__::__always_inline__]] + static void + _S_fill_ampm(_CharT* __buf, chrono::hours __h) + { + auto __hi = __h.count(); + if (__hi >= 24) [[unlikely]] + __hi %= 24; + + constexpr const _CharT* __apm = _GLIBCXX_WIDEN("APM"); + __buf[0] = __apm[__hi >= 12]; + __buf[1] = __apm[2]; + } + // Returns decimal representation of __n. // Returned string_view may point to __buf. [[__gnu__::__always_inline__]] @@ -1879,7 +1889,6 @@ namespace __format }; using __formatter_chrono<_CharT>::__formatter_chrono; - using __formatter_chrono<_CharT>::_M_locale; using __formatter_chrono<_CharT>::_M_spec; template<typename _Duration, typename _ParseContext> @@ -1909,6 +1918,17 @@ namespace __format return __res; } + // Return the formatting locale. + template<typename _FormatContext> + std::locale + _M_locale(_FormatContext& __fc) const + { + if (!_M_spec._M_localized) + return std::locale::classic(); + else + return __fc.locale(); + } + // Format duration for empty chrono-specs, e.g. "{}" (C++20 [time.format] p6). template<typename _Rep, typename _Period, typename _FormatContext> typename _FormatContext::iterator -- 2.49.0