[llvm] [Offload] Full AMD support for olMemFill (PR #154958)

[Ross Brunton via llvm-commits]

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@@ -89,6 +89,40 @@ template <typename Fn> inline void threadify(Fn body) {
   }
 }
 
+/// Enqueues a task to the queue that can be manually resolved.
+// It will block until `trigger` is called.
+struct ManuallyTriggeredTask {
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RossBrunton wrote:

The AMD driver has two different code paths depending on whether the queue is empty or not. This struct allows the test framework to "hold" a task in the queue making it non-empty so that the non-empty path can be tested.

https://github.com/llvm/llvm-project/pull/154958