[llvm] WIP: [Offload] Add testing for Offload program and kernel related entry points (PR #127803)

[Callum Fare via llvm-commits]

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@@ -104,3 +104,15 @@ def : Function {
     Return<"OL_ERRC_INVALID_DEVICE">
   ];
 }
+
+def : Function {
+  let name = "olGetHostDevice";
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callumfare wrote:

I'm a little wary of having a device discovered the regular way that a user can't actually enqueue work on (hopefully it will be usable that way, but as you've suggested in other comments the host plugin needs a bit of work).

But having the user check the device type to find the host device isn't too onerous so I can make this change.

https://github.com/llvm/llvm-project/pull/127803