[llvm] [OFFLOAD] Add support for indexed per-thread containers (PR #164263)

[Kevin Sala Penades via llvm-commits]

================
@@ -16,17 +16,93 @@
 #include <list>
 #include <memory>
 #include <mutex>
+#include <type_traits>
+
+template <typename ObjectType> struct PerThread {
+  struct PerThreadData {
+    std::unique_ptr<ObjectType> ThreadEntry;
+  };
+
+  std::mutex Mutex;
+  std::list<std::shared_ptr<PerThreadData>> ThreadDataList;
+
+  // define default constructors, disable copy and move constructors
+  PerThread() = default;
+  PerThread(const PerThread &) = delete;
+  PerThread(PerThread &&) = delete;
+  PerThread &operator=(const PerThread &) = delete;
+  PerThread &operator=(PerThread &&) = delete;
+  ~PerThread() {
+    std::lock_guard<std::mutex> Lock(Mutex);
+    ThreadDataList.clear();
----------------
kevinsala wrote:

That probably should be more like an assert (i.e., verifying nobody has the lock) than acquiring the lock. At that point, if another thread has the lock, it's probably that something went very wrong.

https://github.com/llvm/llvm-project/pull/164263