[SYCL] Add missing aliases to swizzles (#13040)

Vector swizzles are currently missing the value_type and vector_t
aliases, as should be inherited from vec. This commit adds these
aliases.

---------

Signed-off-by: Larsen, Steffen <[email protected]>

Author: steffenlarsen

sycl/include/sycl/types.hpp

@@ -1790,6 +1790,11 @@ class SwizzleOp {
 
 public:
   using element_type = DataT;
+  using value_type = DataT;
+
+#ifdef __SYCL_DEVICE_ONLY__
+  using vector_t = typename vec_t::vector_t;
+#endif // __SYCL_DEVICE_ONLY__
 
   const DataT &operator[](int i) const {
     std::array<int, getNumElements()> Idxs{Indexes...};

sycl/test/basic_tests/vectors/swizzle_aliases.cpp

@@ -0,0 +1,17 @@
+// RUN: %clangxx -fsycl -fsyntax-only %s
+
+#include <sycl/sycl.hpp>
+
+int main() {
+  sycl::queue Q;
+  Q.single_task([]() {
+    sycl::vec<int, 4> X{1};
+    static_assert(std::is_same_v<decltype(X.swizzle<0>())::element_type, int>);
+    static_assert(std::is_same_v<decltype(X.swizzle<0>())::value_type, int>);
+#ifdef __SYCL_DEVICE_ONLY__
+    static_assert(std::is_same_v<decltype(X.swizzle<0>())::vector_t,
+                                 sycl::vec<int, 1>::vector_t>);
+#endif // __SYCL_DEVICE_ONLY__
+  });
+  return 0;
+}