[SYCL] Add SYCL-2020 interop_handle::get_backend() method (#3664)

The corresponding patch in LIT tests:
intel/llvm-test-suite#258

Signed-off-by: Vyacheslav N Klochkov <vyacheslav.n.klochkov@intel.com>

Author: v-klochkov

sycl/include/CL/sycl/interop_handle.hpp

@@ -36,6 +36,12 @@ class context;
 
 class interop_handle {
 public:
+  interop_handle() = delete;
+
+  /// Returns a backend associated with the queue associated with this
+  /// interop_handle.
+  __SYCL_EXPORT backend get_backend() const noexcept;
+
   /// Receives a SYCL accessor that has been defined as a requirement for the
   /// command group, and returns the underlying OpenCL memory object that is
   /// used by the SYCL runtime. If the accessor passed as parameter is not part
@@ -131,15 +137,13 @@ class interop_handle {
   friend class detail::DispatchHostTask;
   using ReqToMem = std::pair<detail::Requirement *, pi_mem>;
 
-  // TODO set c-tor private
   interop_handle(std::vector<ReqToMem> MemObjs,
                  const std::shared_ptr<detail::queue_impl> &Queue,
                  const std::shared_ptr<detail::device_impl> &Device,
                  const std::shared_ptr<detail::context_impl> &Context)
       : MQueue(Queue), MDevice(Device), MContext(Context),
         MMemObjs(std::move(MemObjs)) {}
 
-private:
   template <backend BackendName, typename DataT, int Dims, access::mode Mode,
             access::target Target, access::placeholder IsPlh>
   auto getMemImpl(detail::Requirement *Req) const ->

sycl/source/interop_handle.cpp

@@ -9,6 +9,7 @@
 #include <CL/sycl/detail/accessor_impl.hpp>
 #include <CL/sycl/exception.hpp>
 #include <CL/sycl/interop_handle.hpp>
+#include <detail/backend_impl.hpp>
 #include <detail/context_impl.hpp>
 #include <detail/device_impl.hpp>
 #include <detail/queue_impl.hpp>
@@ -18,6 +19,10 @@
 __SYCL_INLINE_NAMESPACE(cl) {
 namespace sycl {
 
+backend interop_handle::get_backend() const noexcept {
+  return detail::getImplBackend(MQueue);
+}
+
 pi_native_handle interop_handle::getNativeMem(detail::Requirement *Req) const {
   auto Iter = std::find_if(std::begin(MMemObjs), std::end(MMemObjs),
                            [=](ReqToMem Elem) { return (Elem.first == Req); });

sycl/test/abi/sycl_symbols_linux.dump

@@ -3908,6 +3908,7 @@ _ZNK2cl4sycl13host_selectorclERKNS0_6deviceE
 _ZNK2cl4sycl14exception_list3endEv
 _ZNK2cl4sycl14exception_list4sizeEv
 _ZNK2cl4sycl14exception_list5beginEv
+_ZNK2cl4sycl14interop_handle11get_backendEv
 _ZNK2cl4sycl14interop_handle12getNativeMemEPNS0_6detail16AccessorImplHostE
 _ZNK2cl4sycl14interop_handle14getNativeQueueEv
 _ZNK2cl4sycl14interop_handle15getNativeDeviceEv