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

[Joseph Huber 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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jhuber6 wrote:

This isn't conflating the `host` plugin, which is barely functional wrapper around `dlopen`. The `host` would just be a special device to aid things like memory transfers. Each device would have a 'trait' that is its underlying 'plugin' implementation, so if someone requests a memcpy between two incompatible devices we should be able to detect that and handle it accordingly.

We talked about this stuff before, but it was over a year ago so I don't blame you for not having it at the front of your mind. I'm hesitant to go the "we'll fix it later" route because in my experience that never happens.

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