improving definitions for our types

Signed-off-by: Dan Hoeflinger <[email protected]>

Author: danhoeflinger

include/oneapi/dpl/pstl/iterator_impl.h

@@ -171,7 +171,7 @@ class zip_forward_iterator
     // On windows, this requires clause is necessary so that concepts in MSVC STL do not detect the iterator as
     // dereferenceable when a source iterator is a sycl_iterator, which is a supported type.
     reference
-    operator*() const _ONEDPL_CPP20_REQUIRES(std::indirectly_readable<_Types> &&...)
+    operator*() const _ONEDPL_CPP20_REQUIRES(std::indirectly_readable<_Types>&&...)
     {
         return __make_references<reference>()(__my_it_, ::std::make_index_sequence<__num_types>());
     }
@@ -235,8 +235,16 @@ class counting_iterator
     counting_iterator() : __my_counter_() {}
     explicit counting_iterator(_Ip __init) : __my_counter_(__init) {}
 
-    reference operator*() const { return __my_counter_; }
-    reference operator[](difference_type __i) const { return *(*this + __i); }
+    reference
+    operator*() const
+    {
+        return __my_counter_;
+    }
+    reference
+    operator[](difference_type __i) const
+    {
+        return *(*this + __i);
+    }
 
     difference_type
     operator-(const counting_iterator& __it) const
@@ -328,17 +336,13 @@ class counting_iterator
         return !(*this < __it);
     }
 
+    friend std::true_type
+    is_passed_directly_in_onedpl_device_policies(const counting_iterator&);
+
   private:
     _Ip __my_counter_;
 };
 
-template <typename T>
-constexpr auto
-is_passed_directly_in_onedpl_device_policies(const oneapi::dpl::counting_iterator<T>&)
-{
-    return std::true_type{};
-}
-
 template <typename... _Types>
 class zip_iterator
 {
@@ -361,13 +365,17 @@ class zip_iterator
     // On windows, this requires clause is necessary so that concepts in MSVC STL do not detect the iterator as
     // dereferenceable when a source iterator is a sycl_iterator, which is a supported type.
     reference
-    operator*() const _ONEDPL_CPP20_REQUIRES(std::indirectly_readable<_Types> &&...)
+    operator*() const _ONEDPL_CPP20_REQUIRES(std::indirectly_readable<_Types>&&...)
     {
         return oneapi::dpl::__internal::__make_references<reference>()(__my_it_,
                                                                        ::std::make_index_sequence<__num_types>());
     }
 
-    reference operator[](difference_type __i) const { return *(*this + __i); }
+    reference
+    operator[](difference_type __i) const
+    {
+        return *(*this + __i);
+    }
 
     difference_type
     operator-(const zip_iterator& __it) const
@@ -467,6 +475,10 @@ class zip_iterator
         return !(*this < __it);
     }
 
+    friend auto
+    is_passed_directly_in_onedpl_device_policies(const zip_iterator&)
+        -> std::conjunction<oneapi::dpl::__internal::is_passed_directly_to_device<_Types> ...>;
+
   private:
     __it_types __my_it_;
 };
@@ -485,16 +497,6 @@ make_zip_iterator(std::tuple<_Tp...> __arg)
     return zip_iterator<_Tp...>(__arg);
 }
 
-template <typename... _Tp>
-constexpr auto
-is_passed_directly_in_onedpl_device_policies(const oneapi::dpl::zip_iterator<_Tp...>&)
-{
-    if constexpr ((oneapi::dpl::__internal::is_passed_directly_to_device_v<_Tp> && ...))
-        return std::true_type{};
-    else
-        return std::false_type{};
-}
-
 template <typename _Iter, typename _UnaryFunc>
 class transform_iterator
 {
@@ -553,7 +555,11 @@ class transform_iterator
     {
         return __my_unary_func_(*__my_it_);
     }
-    reference operator[](difference_type __i) const { return *(*this + __i); }
+    reference
+    operator[](difference_type __i) const
+    {
+        return *(*this + __i);
+    }
     transform_iterator&
     operator++()
     {
@@ -653,15 +659,11 @@ class transform_iterator
     {
         return __my_unary_func_;
     }
+    friend auto
+    is_passed_directly_in_onedpl_device_policies(const transform_iterator&)
+        -> oneapi::dpl::__internal::is_passed_directly_to_device<_Iter>;
 };
 
-template <typename _It, typename _Unary>
-constexpr auto
-is_passed_directly_in_onedpl_device_policies(const oneapi::dpl::transform_iterator<_It, _Unary>&)
-{
-    return __internal::is_passed_directly_to_device<_It>{};
-}
-
 template <typename _Iter, typename _UnaryFunc>
 transform_iterator<_Iter, _UnaryFunc>
 make_transform_iterator(_Iter __it, _UnaryFunc __unary_func)
@@ -745,12 +747,16 @@ class permutation_iterator
     // dereferenceable when the source or map iterator is a sycl_iterator, which is a supported type for both.
     reference
     operator*() const
-        _ONEDPL_CPP20_REQUIRES(std::indirectly_readable<SourceIterator> && std::indirectly_readable<IndexMap>)
+        _ONEDPL_CPP20_REQUIRES(std::indirectly_readable<SourceIterator>&& std::indirectly_readable<IndexMap>)
     {
         return my_source_it[*my_index];
     }
 
-    reference operator[](difference_type __i) const { return *(*this + __i); }
+    reference
+    operator[](difference_type __i) const
+    {
+        return *(*this + __i);
+    }
 
     permutation_iterator&
     operator++()
@@ -851,6 +857,10 @@ class permutation_iterator
         return !(*this < it);
     }
 
+    friend auto is_passed_directly_in_onedpl_device_policies(const permutation_iterator&) -> std::conjunction<oneapi::dpl::__internal::is_passed_directly_to_device<SourceIterator>, 
+        oneapi::dpl::__internal::is_passed_directly_to_device<
+        typename oneapi::dpl::permutation_iterator<SourceIterator, _Permutation>::IndexMap>>;
+
   private:
     SourceIterator my_source_it;
     IndexMap my_index;
@@ -923,8 +933,16 @@ class discard_iterator
     discard_iterator() : __my_position_() {}
     explicit discard_iterator(difference_type __init) : __my_position_(__init) {}
 
-    reference operator*() const { return internal::ignore; }
-    reference operator[](difference_type) const { return internal::ignore; }
+    reference
+    operator*() const
+    {
+        return internal::ignore;
+    }
+    reference
+    operator[](difference_type) const
+    {
+        return internal::ignore;
+    }
 
     // GCC Bug 66297: constexpr non-static member functions of non-literal types
 #if __GNUC__ && _ONEDPL_GCC_VERSION < 70200 && !(__INTEL_COMPILER || __clang__)
@@ -1025,15 +1043,14 @@ class discard_iterator
         return !(*this < __it);
     }
 
-  private:
+    friend std::true_type
+    is_passed_directly_in_onedpl_device_policies(const discard_iterator&);
+
+    private:
     difference_type __my_position_;
 };
 
-constexpr auto
-is_passed_directly_in_onedpl_device_policies(const oneapi::dpl::discard_iterator&)
-{
-    return std::true_type{};
-}
+
 
 } // namespace dpl
 } // namespace oneapi