[llvm] [offload] Add `dlwrap::loaded` function to check for optional symbols (PR #210737)

[Łukasz Plewa via llvm-commits]

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@@ -143,13 +137,16 @@ static ze_result_t zeCommandListAppendLaunchKernelWithArgumentsFallback(
       }
     }
   });
-  if (!zexKernelGetArgumentSize_ptr) {
-    ODBG(OLDT_Kernel) << "zeCommandListAppendLaunchKernelWithArguments is not "
-                         "available, and no fallback is possible without "
-                         "argument size information.";
-    return ZE_RESULT_ERROR_UNSUPPORTED_FEATURE;
-  }
+  return zexKernelGetArgumentSize_ptr != nullptr;
+}
+
+static ze_result_t zeCommandListAppendLaunchKernelWithArgumentsFallback(
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lplewa wrote:

We are before zeInit(), so you should not use level zero calls before

https://github.com/llvm/llvm-project/pull/210737