Re: Re: [PATCH 08/14] libstdc++: Optimize std::is_compound compilation performance

[Ken Matsui <kmatsui@gcc.gnu.org>]

On 01-10 (21:21), Jonathan Wakely wrote:
> On Wed, 10 Jan 2024 at 19:41, Ken Matsui <kmatsui@gcc.gnu.org> wrote:
> >
> > This patch optimizes the compilation performance of std::is_compound
> > by dispatching to the new __is_arithmetic built-in trait.
> 
> OK for trunk (no need to wait for anything else to be approved).
> 
Thank you for your all reviews!  This commit message is not quite accurate,
so I will update it before committing.

> >
> > libstdc++-v3/ChangeLog:
> >
> >         * include/std/type_traits (is_compound): Do not use __not_.
> >         (is_compound_v): Use is_fundamental_v instead.
> >
> > Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
> > ---
> >  libstdc++-v3/include/std/type_traits | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
> > index 1c560d97e85..6294f5af533 100644
> > --- a/libstdc++-v3/include/std/type_traits
> > +++ b/libstdc++-v3/include/std/type_traits
> > @@ -784,7 +784,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> >    /// is_compound
> >    template<typename _Tp>
> >      struct is_compound
> > -    : public __not_<is_fundamental<_Tp>>::type { };
> > +    : public __bool_constant<!is_fundamental<_Tp>::value> { };
> >
> >    /// is_member_pointer
> >  #if _GLIBCXX_USE_BUILTIN_TRAIT(__is_member_pointer)
> > @@ -3358,7 +3358,7 @@ template <typename _Tp>
> >  template <typename _Tp>
> >    inline constexpr bool is_scalar_v = is_scalar<_Tp>::value;
> >  template <typename _Tp>
> > -  inline constexpr bool is_compound_v = is_compound<_Tp>::value;
> > +  inline constexpr bool is_compound_v = !is_fundamental_v<_Tp>;
> >
> >  #if _GLIBCXX_USE_BUILTIN_TRAIT(__is_member_pointer)
> >  template <typename _Tp>
> > --
> > 2.43.0
> >
>