[oneDPL][sycl] changes in __dpl_sycl::submit - support setting depend…

…encies as __dpl_sycl::__event or sycl::event or std:vector<sycl::event>

include/oneapi/dpl/pstl/hetero/dpcpp/sycl_defs.h

@@ -420,44 +420,66 @@ class __event
 {
     sycl::event __m_event;
     sycl::queue __m_queue;
-    bool __in_order = false;
+    bool __m_queue_synch;
 
   public:
-    __event(sycl::event __e): __m_event(__e) {}
-    __event() {}
-
-    __event(sycl::queue __q): __m_queue(__q), __in_order(true) {}
+    __event(sycl::event __e = {}): __m_event(__e), __m_queue_synch(false) {}
+    __event(sycl::queue __q): __m_queue(__q), __m_queue_synch(true) 
+    {
+        assert(__q.is_in_order());
+    }
 
     void wait()
     {
-        if(__in_order)
+        if(__m_queue_synch)
             __m_queue.wait_and_throw();
         else
             __m_event.wait_and_throw();
     }
 
-    bool has_event() const { return !__in_order; }
     operator sycl::event() const
     { 
-        assert(has_event());
+        assert(!__m_queue_synch);
         return __m_event;
     }
 };
 
-template <typename _Body>
+template <typename _Body, typename _DependencyInternal, typename _DependencyExternal>
 auto
-__submit(sycl::queue __queue, _Body __body, __event __e = {})
+__submit_impl(sycl::queue __queue, _Body __body, bool __is_implicit_synch, const _DependencyInternal* __dep_int, const _DependencyExternal* __dep_ext)
 {
-     if(__queue.is_in_order())
-     {
-        __queue.submit(__body);
+    if(__queue.is_in_order() || __is_implicit_synch)
+    {
+        __queue.submit([&](sycl::handler& __hdl) {
+            if(__dep_ext)
+                __hdl.depends_on(*__dep_ext);
+                __body(__hdl);
+            });
         return __event(__queue);
-     }
+    }
+
+    return __event(__queue.submit([&](sycl::handler& __hdl) {
+        assert(!__is_implicit_synch);
+        if(__dep_ext)
+           __hdl.depends_on(*__dep_ext);
+       if(__dep_int)
+           __hdl.depends_on(*__dep_int);
+       __body(__hdl);
+       }));
+}
 
-     return __event(__queue.submit([&](sycl::handler& __hdl) {
-        __hdl.depends_on(__e);
-        __body(__hdl);
-        }));
+template <typename _Body>
+auto
+__submit(sycl::queue __queue, _Body __body)
+{
+    return __submit_impl(__queue, __body, true);
+}
+
+template <typename _Body, typename _Dependency>
+auto
+__submit(sycl::queue __queue, _Body __body, const _Dependency& __dependency)
+{
+    return __submit_impl(__queue, __body, false, &__dependency, NULL);
 }
 
 } // namespace __dpl_sycl