[PING][PATCH v10 3/5] c++: Implement __is_function built-in trait

[Ken Matsui <kmatsui@cs.washington.edu>]

Ping for __is_function built-in.

Sincerely,
Ken Matsui


On Tue, Aug 22, 2023 at 12:53 PM Patrick Palka <ppalka@redhat.com> wrote:
>
> On Wed, 12 Jul 2023, Ken Matsui via Libstdc++ wrote:
>
> > This patch implements built-in trait for std::is_function.
> >
> > gcc/cp/ChangeLog:
> >
> >       * cp-trait.def: Define __is_function.
> >       * constraint.cc (diagnose_trait_expr): Handle CPTK_IS_FUNCTION.
> >       * semantics.cc (trait_expr_value): Likewise.
> >       (finish_trait_expr): Likewise.
> >
> > gcc/testsuite/ChangeLog:
> >
> >       * g++.dg/ext/has-builtin-1.C: Test existence of __is_function.
> >       * g++.dg/ext/is_function.C: New test.
>
> LGTM!
>
> >
> > Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
> > ---
> >  gcc/cp/constraint.cc                     |  3 ++
> >  gcc/cp/cp-trait.def                      |  1 +
> >  gcc/cp/semantics.cc                      |  4 ++
> >  gcc/testsuite/g++.dg/ext/has-builtin-1.C |  3 ++
> >  gcc/testsuite/g++.dg/ext/is_function.C   | 58 ++++++++++++++++++++++++
> >  5 files changed, 69 insertions(+)
> >  create mode 100644 gcc/testsuite/g++.dg/ext/is_function.C
> >
> > diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
> > index f6951ee2670..927605c6cb7 100644
> > --- a/gcc/cp/constraint.cc
> > +++ b/gcc/cp/constraint.cc
> > @@ -3754,6 +3754,9 @@ diagnose_trait_expr (tree expr, tree args)
> >      case CPTK_IS_UNION:
> >        inform (loc, "  %qT is not a union", t1);
> >        break;
> > +    case CPTK_IS_FUNCTION:
> > +      inform (loc, "  %qT is not a function", t1);
> > +      break;
> >      case CPTK_IS_AGGREGATE:
> >        inform (loc, "  %qT is not an aggregate", t1);
> >        break;
> > diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
> > index 1e3310cd682..3cd3babc242 100644
> > --- a/gcc/cp/cp-trait.def
> > +++ b/gcc/cp/cp-trait.def
> > @@ -83,6 +83,7 @@ DEFTRAIT_EXPR (IS_TRIVIALLY_ASSIGNABLE, "__is_trivially_assignable", 2)
> >  DEFTRAIT_EXPR (IS_TRIVIALLY_CONSTRUCTIBLE, "__is_trivially_constructible", -1)
> >  DEFTRAIT_EXPR (IS_TRIVIALLY_COPYABLE, "__is_trivially_copyable", 1)
> >  DEFTRAIT_EXPR (IS_UNION, "__is_union", 1)
> > +DEFTRAIT_EXPR (IS_FUNCTION, "__is_function", 1)
> >  DEFTRAIT_EXPR (REF_CONSTRUCTS_FROM_TEMPORARY, "__reference_constructs_from_temporary", 2)
> >  DEFTRAIT_EXPR (REF_CONVERTS_FROM_TEMPORARY, "__reference_converts_from_temporary", 2)
> >  /* FIXME Added space to avoid direct usage in GCC 13.  */
> > diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
> > index 2f37bc353a1..b976633645a 100644
> > --- a/gcc/cp/semantics.cc
> > +++ b/gcc/cp/semantics.cc
> > @@ -12072,6 +12072,9 @@ trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
> >      case CPTK_IS_ENUM:
> >        return type_code1 == ENUMERAL_TYPE;
> >
> > +    case CPTK_IS_FUNCTION:
> > +      return type_code1 == FUNCTION_TYPE;
> > +
> >      case CPTK_IS_FINAL:
> >        return CLASS_TYPE_P (type1) && CLASSTYPE_FINAL (type1);
> >
> > @@ -12293,6 +12296,7 @@ finish_trait_expr (location_t loc, cp_trait_kind kind, tree type1, tree type2)
> >      case CPTK_IS_UNION:
> >      case CPTK_IS_SAME:
> >      case CPTK_IS_REFERENCE:
> > +    case CPTK_IS_FUNCTION:
> >        break;
> >
> >      case CPTK_IS_LAYOUT_COMPATIBLE:
> > diff --git a/gcc/testsuite/g++.dg/ext/has-builtin-1.C b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> > index b697673790c..90eb00ebf2d 100644
> > --- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> > +++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> > @@ -149,3 +149,6 @@
> >  #if !__has_builtin (__is_reference)
> >  # error "__has_builtin (__is_reference) failed"
> >  #endif
> > +#if !__has_builtin (__is_function)
> > +# error "__has_builtin (__is_function) failed"
> > +#endif
> > diff --git a/gcc/testsuite/g++.dg/ext/is_function.C b/gcc/testsuite/g++.dg/ext/is_function.C
> > new file mode 100644
> > index 00000000000..2e1594b12ad
> > --- /dev/null
> > +++ b/gcc/testsuite/g++.dg/ext/is_function.C
> > @@ -0,0 +1,58 @@
> > +// { dg-do compile { target c++11 } }
> > +
> > +#include <testsuite_tr1.h>
> > +
> > +using namespace __gnu_test;
> > +
> > +#define SA(X) static_assert((X),#X)
> > +#define SA_TEST_CATEGORY(TRAIT, TYPE, EXPECT)        \
> > +  SA(TRAIT(TYPE) == EXPECT);                                 \
> > +  SA(TRAIT(const TYPE) == EXPECT);                           \
> > +  SA(TRAIT(volatile TYPE) == EXPECT);                        \
> > +  SA(TRAIT(const volatile TYPE) == EXPECT)
> > +
> > +struct A
> > +{ void fn(); };
> > +
> > +template<typename>
> > +struct AHolder { };
> > +
> > +template<class T, class U>
> > +struct AHolder<U T::*>
> > +{ using type = U; };
> > +
> > +// Positive tests.
> > +SA(__is_function(int (int)));
> > +SA(__is_function(ClassType (ClassType)));
> > +SA(__is_function(float (int, float, int[], int&)));
> > +SA(__is_function(int (int, ...)));
> > +SA(__is_function(bool (ClassType) const));
> > +SA(__is_function(AHolder<decltype(&A::fn)>::type));
> > +
> > +void fn();
> > +SA(__is_function(decltype(fn)));
> > +
> > +// Negative tests.
> > +SA_TEST_CATEGORY(__is_function, int, false);
> > +SA_TEST_CATEGORY(__is_function, int*, false);
> > +SA_TEST_CATEGORY(__is_function, int&, false);
> > +SA_TEST_CATEGORY(__is_function, void, false);
> > +SA_TEST_CATEGORY(__is_function, void*, false);
> > +SA_TEST_CATEGORY(__is_function, void**, false);
> > +SA_TEST_CATEGORY(__is_function, std::nullptr_t, false);
> > +
> > +SA_TEST_CATEGORY(__is_function, AbstractClass, false);
> > +SA(!__is_function(int(&)(int)));
> > +SA(!__is_function(int(*)(int)));
> > +
> > +SA_TEST_CATEGORY(__is_function, A, false);
> > +SA_TEST_CATEGORY(__is_function, decltype(&A::fn), false);
> > +
> > +struct FnCallOverload
> > +{ void operator()(); };
> > +SA_TEST_CATEGORY(__is_function, FnCallOverload, false);
> > +
> > +// Sanity check.
> > +SA_TEST_CATEGORY(__is_function, ClassType, false);
> > +SA_TEST_CATEGORY(__is_function, IncompleteClass, false);
> > +SA_TEST_CATEGORY(__is_function, IncompleteUnion, false);
> > --
> > 2.41.0
> >
> >
>