[llvm] [Offload] Implement the remaining initial Offload API (PR #122106)

[Callum Fare via llvm-commits]

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@@ -16,8 +16,8 @@ def : Function {
     let details = [];
     let params = [
         Param<"ol_queue_handle_t", "Queue", "handle of the queue", PARAM_IN>,
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callumfare wrote:

The queue does know which device it belongs to. But I think for a single memcpy to work you'd need to know whether the src and dst pointers are device/shared allocations or host pointers, to know whether to call through to `dataSubmit`, `dataRetrieve`, or `dataExchange` in the plugin interface.


https://github.com/llvm/llvm-project/pull/122106