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

[Callum Fare via llvm-commits]

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@@ -1088,26 +1089,33 @@ olEnqueueKernelLaunch_val(ol_queue_handle_t Queue, ol_kernel_handle_t Kernel,
       return OL_ERRC_INVALID_NULL_HANDLE;
     }
 
+    if (NULL == ArgumentsData) {
+      return OL_ERRC_INVALID_NULL_POINTER;
+    }
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callumfare wrote:

These checks appear in the auto-generated documentation, where I think it's better to have it explicitly spelled out as `NULL == x`

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