[llvm] [OFFLOAD] Add plugin with support for Intel oneAPI Level Zero (PR #158900)

[Alexey Sachkov via llvm-commits]

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@@ -0,0 +1,50 @@
+//===--- Level Zero Target RTL Implementation -----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Async Queue wrapper for SPIR-V/Xe machine
+//
+//===----------------------------------------------------------------------===//
+
+#pragma once
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AlexeySachkov wrote:

For my own education: does `offload` has a customization of [LLVM Coding Standards](https://llvm.org/docs/CodingStandards.html)?

AFAIK, the general rule is that `#pragma once` is a non-standard C++ extension and therefore regular `#ifdef` guards should be used.

https://github.com/llvm/llvm-project/pull/158900