[SYCL][Unittests] Fix unloading of mock images on Windows

sycl/source/detail/global_handler.cpp

@@ -134,6 +134,10 @@ GlobalHandler &GlobalHandler::instance() {
   return *RTGlobalObjHandler;
 }
 
+bool GlobalHandler::isInstanceAlive() {
+  return GlobalHandler::getInstancePtr();
+}
+
 template <typename T, typename... Types>
 T &GlobalHandler::getOrCreate(InstWithLock<T> &IWL, Types &&...Args) {
   const LockGuard Lock{IWL.Lock};

sycl/source/detail/global_handler.hpp

@@ -52,6 +52,9 @@ class GlobalHandler {
   /// `__attribute__((destructor))` is called).
   static GlobalHandler &instance();
 
+  /// \return true if the instance has not been deallocated yet.
+  static bool isInstanceAlive();
+
   GlobalHandler(const GlobalHandler &) = delete;
   GlobalHandler(GlobalHandler &&) = delete;
   GlobalHandler &operator=(const GlobalHandler &) = delete;

sycl/unittests/helpers/MockDeviceImage.hpp

@@ -363,10 +363,15 @@ template <size_t __NumberOfImages> class MockDeviceImageArray {
         nullptr, // not used, put here for compatibility with OpenMP
     };
 
-    __sycl_register_lib(&MAllBinaries);
+    sycl::detail::ProgramManager::getInstance().addImages(&MAllBinaries);
   }
 
-  ~MockDeviceImageArray() { __sycl_unregister_lib(&MAllBinaries); }
+  ~MockDeviceImageArray() {
+    // If there is still a global handler, we are not doing full unloading yet.
+    // As such, we need to clean up the images we registered.
+    if (GlobalHandler::isInstanceAlive())
+      sycl::detail::ProgramManager::getInstance().removeImages(&MAllBinaries);
+  }
 
 private:
   sycl_device_binary_struct MNativeImages[NumberOfImages];