Fix command-buffer dependencies on the legacy adapter when immediate command lists are disabled

Author: fabiomestre

unified-runtime/source/adapters/level_zero/command_buffer.cpp

@@ -1489,6 +1489,25 @@ ur_result_t waitForDependencies(ur_exp_command_buffer_handle_t CommandBuffer,
   std::scoped_lock<ur_shared_mutex> Guard(CommandBuffer->Mutex);
   const bool UseCopyEngine = false;
   bool MustSignalWaitEvent = true;
+
+  // Level-zero does not allow in-order queue when immediate command-lists are
+  // not used. For that reason, if the UR queue is in-order, we need to emulate,
+  // its in-order properties by adding an event dependency on the last command
+  // executed by the queue.
+  std::vector<ur_event_handle_t> WaitList;
+  if (Queue->isInOrderQueue() && Queue->LastCommandEvent) {
+    WaitList.reserve(NumEventsInWaitList + 1);
+
+    if (NumEventsInWaitList) {
+      WaitList.insert(WaitList.end(), EventWaitList,
+                      EventWaitList + NumEventsInWaitList);
+    }
+    WaitList.push_back(Queue->LastCommandEvent);
+
+    ++NumEventsInWaitList;
+    EventWaitList = WaitList.data();
+  }
+
   if (NumEventsInWaitList) {
     ur_ze_event_list_t TmpWaitList;
     UR_CALL(TmpWaitList.createAndRetainUrZeEventList(