[llvm] [Offload] Add device UID (PR #164391)

[Kevin Sala Penades via llvm-commits]

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@@ -148,7 +148,9 @@ struct GenELF64DeviceTy : public GenericDeviceTy {
   /// Create the device with a specific id.
   GenELF64DeviceTy(GenericPluginTy &Plugin, int32_t DeviceId,
                    int32_t NumDevices)
-      : GenericDeviceTy(Plugin, DeviceId, NumDevices, GenELF64GridValues) {}
+      : GenericDeviceTy(Plugin, DeviceId, NumDevices, GenELF64GridValues) {
+    DeviceUid = getHostDeviceUid();
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kevinsala wrote:

But if they are exposed as separate OpenMP devices, I suppose they should have unique uids as well; otherwise it won't conform to the standard.

https://github.com/llvm/llvm-project/pull/164391