Fix for iterators with const-qualified value type (#1527)

const qualified type iterators were causing problems when checking for usm std::vector iterators because of the way that check must be, we were instantiating ill-formed std::vectors during the check, resulting in static assertions being triggered. This avoids any types which result in ill-formed vectors, as they cannot be eligible anyway. --------- Signed-off-by: Dan Hoeflinger <[email protected]>
oneapi-src · Apr 25, 2024 · 141aa38 · 141aa38
1 parent 089fbb9
commit 141aa38
Show file tree

Hide file tree

Showing 2 changed files with 32 additions and 5 deletions.
diff --git a/include/oneapi/dpl/pstl/hetero/dpcpp/sycl_iterator.h b/include/oneapi/dpl/pstl/hetero/dpcpp/sycl_iterator.h
@@ -177,6 +177,36 @@ struct __vector_iter_distinguishes_by_allocator<
 {
 };
 
+template <typename Iter, typename Void = void>
+struct __is_known_usm_vector_iter_impl : std::false_type
+{
+};
+
+template <typename Iter>
+struct __is_known_usm_vector_iter_impl<
+    Iter, std::enable_if_t<std::conjunction<
+              std::disjunction<std::is_same<Iter, oneapi::dpl::__internal::__usm_shared_alloc_vec_iter<Iter>>,
+                               std::is_same<Iter, oneapi::dpl::__internal::__usm_host_alloc_vec_iter<Iter>>>,
+              oneapi::dpl::__internal::__vector_iter_distinguishes_by_allocator<Iter>>::value>> : std::true_type
+{
+};
+
+template <typename Iter, typename Void = void>
+struct __is_known_usm_vector_iter : std::false_type
+{
+};
+
+//We must avoid instantiating vector of const, reference, or function elements to avoid ill-formed vector instantiation
+template <typename Iter>
+struct __is_known_usm_vector_iter<
+    Iter, std::enable_if_t<std::conjunction<
+              std::negation<std::disjunction<std::is_const<typename std::iterator_traits<Iter>::value_type>,
+                                             std::is_reference<typename std::iterator_traits<Iter>::value_type>,
+                                             std::is_function<typename std::iterator_traits<Iter>::value_type>>>,
+              oneapi::dpl::__internal::__is_known_usm_vector_iter_impl<Iter>>::value>> : std::true_type
+{
+};
+
 } // namespace __internal
 
 template <typename T, typename Allocator>

diff --git a/include/oneapi/dpl/pstl/hetero/dpcpp/utils_ranges_sycl.h b/include/oneapi/dpl/pstl/hetero/dpcpp/utils_ranges_sycl.h
@@ -209,11 +209,8 @@ struct is_passed_directly<Iter, ::std::enable_if_t<Iter::is_passed_directly::val
 
 //support std::vector::iterator with usm host / shared allocator as passed directly
 template <typename Iter>
-struct is_passed_directly<
-    Iter, std::enable_if_t<(std::is_same_v<Iter, oneapi::dpl::__internal::__usm_shared_alloc_vec_iter<Iter>> ||
-                            std::is_same_v<Iter, oneapi::dpl::__internal::__usm_host_alloc_vec_iter<Iter>>) &&
-                            oneapi::dpl::__internal::__vector_iter_distinguishes_by_allocator<Iter>::value>> :
-                                std::true_type
+struct is_passed_directly<Iter, std::enable_if_t<oneapi::dpl::__internal::__is_known_usm_vector_iter<Iter>::value>>
+    : std::true_type
 {
 };