[UR][Offload] Fix offload adapter after #18901 (#18926)

We were storing handles in vectors, which is now forbidden.

Author: RossBrunton

unified-runtime/source/adapters/offload/adapter.cpp

@@ -43,15 +43,17 @@ ur_result_t ur_adapter_handle_t_::init() {
         } else if (Backend != OL_PLATFORM_BACKEND_UNKNOWN) {
           auto URPlatform =
               std::find_if(Platforms->begin(), Platforms->end(), [&](auto &P) {
-                return P.OffloadPlatform == Platform;
+                return P->OffloadPlatform == Platform;
               });
 
           if (URPlatform == Platforms->end()) {
-            URPlatform =
-                Platforms->insert(URPlatform, ur_platform_handle_t_(Platform));
+            URPlatform = Platforms->insert(
+                URPlatform, std::make_unique<ur_platform_handle_t_>(Platform));
           }
 
-          URPlatform->Devices.push_back(ur_device_handle_t_{&*URPlatform, D});
+          (*URPlatform)
+              ->Devices.push_back(
+                  std::make_unique<ur_device_handle_t_>(URPlatform->get(), D));
         }
         return false;
       },

unified-runtime/source/adapters/offload/adapter.hpp

@@ -24,7 +24,7 @@ struct ur_adapter_handle_t_ : ur::offload::handle_base {
   std::atomic_uint32_t RefCount = 0;
   logger::Logger &Logger = logger::get_logger("offload");
   ol_device_handle_t HostDevice = nullptr;
-  std::vector<ur_platform_handle_t_> Platforms;
+  std::vector<std::unique_ptr<ur_platform_handle_t_>> Platforms;
 
   ur_result_t init();
 };

unified-runtime/source/adapters/offload/device.cpp

@@ -29,7 +29,7 @@ UR_APIEXPORT ur_result_t UR_APICALL urDeviceGet(ur_platform_handle_t hPlatform,
       std::min(static_cast<uint32_t>(hPlatform->Devices.size()), NumEntries);
 
   for (size_t I = 0; I < NumDevices; I++) {
-    phDevices[I] = &hPlatform->Devices[I];
+    phDevices[I] = hPlatform->Devices[I].get();
   }
 
   return UR_RESULT_SUCCESS;

unified-runtime/source/adapters/offload/platform.cpp

@@ -28,7 +28,7 @@ urPlatformGet(ur_adapter_handle_t, uint32_t NumEntries,
   if (phPlatforms) {
     size_t PlatformIndex = 0;
     for (auto &Platform : Adapter.Platforms) {
-      phPlatforms[PlatformIndex++] = &Platform;
+      phPlatforms[PlatformIndex++] = Platform.get();
       if (PlatformIndex == NumEntries) {
         break;
       }

unified-runtime/source/adapters/offload/platform.hpp

@@ -20,5 +20,5 @@ struct ur_platform_handle_t_ : ur::offload::handle_base {
       : handle_base(), OffloadPlatform(OffloadPlatform) {};
 
   ol_platform_handle_t OffloadPlatform;
-  std::vector<ur_device_handle_t_> Devices;
+  std::vector<std::unique_ptr<ur_device_handle_t_>> Devices;
 };