[llvm] [OFFLOAD] Add missing API for libomptarget migration (PR #171009)

[via llvm-commits]

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@@ -1214,5 +1229,109 @@ Error olLaunchHostFunction_impl(ol_queue_handle_t Queue,
                                                 Queue->AsyncInfo);
 }
 
+Error olDataFence_impl(ol_queue_handle_t Queue) {
+  if (Queue->AsyncInfo->Queue) {
+    if (auto Err = Queue->Device->Device->dataFence(Queue->AsyncInfo))
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fineg74 wrote:

It is pretty common in liboffload code: bunch of classes have members called Device although in different classes they mean different things (liboffload Device type vs GenericDeviceTy from libomptarget). BTW, there is similar issue in libomptarget as well where we have different device types that abstract actual device on different API levels.

https://github.com/llvm/llvm-project/pull/171009