| Message ID | 20240117023641.3389770-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | libstdc++/ranges: Define _S_has_simple_call_op on newer adaptors | expand |
On Wed, 17 Jan 2024, 02:37 Patrick Palka, <ppalka@redhat.com> wrote: > Tested on x86_64-pc-linux-gnu, does this look OK for trunk? > OK > -- >8 -- > > This compile-time and diagnostic improvement[1] is less important in > C++23 mode where deducing this is available and used in _Pipe, but for > benefit of C++20 mode and for consistency let's set the flag on the most > recently added range adaptors which lack it. > > [1]: Defining _S_has_simple_call_op=true for a range adaptor closure > object signals that the adaptor has an operator() that's not overloaded > according to the constness/value category of the object, which in turn > allows us to implement the operator() of the composition of such adaptors > in a simpler way. > > libstdc++-v3/ChangeLog: > > * include/std/ranges (views::_Adjacent::_S_has_simple_call_op): > Define to true. > (views::_AsRvalue::_S_has_simple_call_op): Likewise. > (views::_Enumerate::_S_has_simple_call_op): Likewise. > (views::_AsConst::_S_has_simple_call_op): Likewise. > --- > libstdc++-v3/include/std/ranges | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/libstdc++-v3/include/std/ranges > b/libstdc++-v3/include/std/ranges > index 7ef835f486a..66502cc1da4 100644 > --- a/libstdc++-v3/include/std/ranges > +++ b/libstdc++-v3/include/std/ranges > @@ -5669,6 +5669,8 @@ namespace views::__adaptor > else > return adjacent_view<all_t<_Range>, > _Nm>(std::forward<_Range>(__r)); > } > + > + static constexpr bool _S_has_simple_call_op = true; > }; > > template<size_t _Nm> > @@ -8844,6 +8846,8 @@ namespace views::__adaptor > else > return as_rvalue_view(std::forward<_Range>(__r)); > } > + > + static constexpr bool _S_has_simple_call_op = true; > }; > > inline constexpr _AsRvalue as_rvalue; > @@ -9147,6 +9151,8 @@ namespace views::__adaptor > constexpr auto > operator() [[nodiscard]] (_Range&& __r) const > { return enumerate_view<all_t<_Range>>(std::forward<_Range>(__r)); > } > + > + static constexpr bool _S_has_simple_call_op = true; > }; > > inline constexpr _Enumerate enumerate; > @@ -9253,6 +9259,8 @@ namespace views::__adaptor > else > return as_const_view(std::forward<_Range>(__r)); > } > + > + static constexpr bool _S_has_simple_call_op = true; > }; > > inline constexpr _AsConst as_const; > -- > 2.43.0.367.g186b115d30 > >
On Wed, 17 Jan 2024, Jonathan Wakely wrote: > > > On Wed, 17 Jan 2024, 02:37 Patrick Palka, <ppalka@redhat.com> wrote: > Tested on x86_64-pc-linux-gnu, does this look OK for trunk? > > > OK Thanks a lot. For the record I ended up not pushing this patch because all the range adaptors it touches are C++23 ones and so ... > > > > -- >8 -- > > This compile-time and diagnostic improvement[1] is less important in > C++23 mode where deducing this is available and used in _Pipe, but for > benefit of C++20 mode ... this isn't true. There's no real benefit in setting this flag for standard C++23 range adaptors (besides consistency I guess, but OTOH not setting it means more testing coverage for the deducing this code path). > and for consistency let's set the flag on the most > recently added range adaptors which lack it. > > [1]: Defining _S_has_simple_call_op=true for a range adaptor closure > object signals that the adaptor has an operator() that's not overloaded > according to the constness/value category of the object, which in turn > allows us to implement the operator() of the composition of such adaptors > in a simpler way. > > libstdc++-v3/ChangeLog: > > * include/std/ranges (views::_Adjacent::_S_has_simple_call_op): > Define to true. > (views::_AsRvalue::_S_has_simple_call_op): Likewise. > (views::_Enumerate::_S_has_simple_call_op): Likewise. > (views::_AsConst::_S_has_simple_call_op): Likewise. > --- > libstdc++-v3/include/std/ranges | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/libstdc++-v3/include/std/ranges b/libstdc++-v3/include/std/ranges > index 7ef835f486a..66502cc1da4 100644 > --- a/libstdc++-v3/include/std/ranges > +++ b/libstdc++-v3/include/std/ranges > @@ -5669,6 +5669,8 @@ namespace views::__adaptor > else > return adjacent_view<all_t<_Range>, _Nm>(std::forward<_Range>(__r)); > } > + > + static constexpr bool _S_has_simple_call_op = true; > }; > > template<size_t _Nm> > @@ -8844,6 +8846,8 @@ namespace views::__adaptor > else > return as_rvalue_view(std::forward<_Range>(__r)); > } > + > + static constexpr bool _S_has_simple_call_op = true; > }; > > inline constexpr _AsRvalue as_rvalue; > @@ -9147,6 +9151,8 @@ namespace views::__adaptor > constexpr auto > operator() [[nodiscard]] (_Range&& __r) const > { return enumerate_view<all_t<_Range>>(std::forward<_Range>(__r)); } > + > + static constexpr bool _S_has_simple_call_op = true; > }; > > inline constexpr _Enumerate enumerate; > @@ -9253,6 +9259,8 @@ namespace views::__adaptor > else > return as_const_view(std::forward<_Range>(__r)); > } > + > + static constexpr bool _S_has_simple_call_op = true; > }; > > inline constexpr _AsConst as_const; > -- > 2.43.0.367.g186b115d30 > > >
diff --git a/libstdc++-v3/include/std/ranges b/libstdc++-v3/include/std/ranges index 7ef835f486a..66502cc1da4 100644 --- a/libstdc++-v3/include/std/ranges +++ b/libstdc++-v3/include/std/ranges @@ -5669,6 +5669,8 @@ namespace views::__adaptor else return adjacent_view<all_t<_Range>, _Nm>(std::forward<_Range>(__r)); } + + static constexpr bool _S_has_simple_call_op = true; }; template<size_t _Nm> @@ -8844,6 +8846,8 @@ namespace views::__adaptor else return as_rvalue_view(std::forward<_Range>(__r)); } + + static constexpr bool _S_has_simple_call_op = true; }; inline constexpr _AsRvalue as_rvalue; @@ -9147,6 +9151,8 @@ namespace views::__adaptor constexpr auto operator() [[nodiscard]] (_Range&& __r) const { return enumerate_view<all_t<_Range>>(std::forward<_Range>(__r)); } + + static constexpr bool _S_has_simple_call_op = true; }; inline constexpr _Enumerate enumerate; @@ -9253,6 +9259,8 @@ namespace views::__adaptor else return as_const_view(std::forward<_Range>(__r)); } + + static constexpr bool _S_has_simple_call_op = true; }; inline constexpr _AsConst as_const;