[llvm] [Offload] Store device info tree in device handle (PR #145913)

[Ross Brunton via llvm-commits]

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@@ -167,31 +167,39 @@ void initPlugins() {
     for (auto DevNum = 0; DevNum < Platform.Plugin->number_of_devices();
          DevNum++) {
       if (Platform.Plugin->init_device(DevNum) == OFFLOAD_SUCCESS) {
-        Platform.Devices.emplace_back(ol_device_impl_t{
-            DevNum, &Platform.Plugin->getDevice(DevNum), &Platform});
+        auto Device = &Platform.Plugin->getDevice(DevNum);
+        auto Info = Device->obtainInfoImpl();
+        if (auto Err = Info.takeError())
+          return Err;
+        Platform.Devices.emplace_back(DevNum, Device, &Platform,
+                                      std::move(*Info));
       }
     }
   }
 
   // Add the special host device
   auto &HostPlatform = Context->Platforms.emplace_back(
-      ol_platform_impl_t{nullptr,
-                         {ol_device_impl_t{-1, nullptr, nullptr}},
-                         OL_PLATFORM_BACKEND_HOST});
+      ol_platform_impl_t{nullptr, OL_PLATFORM_BACKEND_HOST});
+  HostPlatform.Devices.emplace_back(-1, nullptr, nullptr, InfoTreeNode{});
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RossBrunton wrote:

Using emplace here because `ol_device_impl_t` can't be copied (since it contains a unique_ptr now). I'm not sure the C++ way of doing this in the initializer list, if there is one.

https://github.com/llvm/llvm-project/pull/145913