[llvm] [SYCL] Add libsycl, a SYCL RT library implementation project (PR #144372)

[Kseniya Tikhomirova via llvm-commits]

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@@ -0,0 +1,64 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file contains the declaration of the macros defining attributes for
+/// exported methods and defining API namespaces.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef __LIBSYCL_DETAIL_CONFIG_HPP
+#define __LIBSYCL_DETAIL_CONFIG_HPP
+
+#include <sycl/version.hpp>
+
+#define __LIBSYCL_BEGIN_UNVERSIONED_NAMESPACE namespace sycl {
+#define __LIBSYCL_END_UNVERSIONED_NAMESPACE }
+
+#define __LIBSYCL_BEGIN_VERSIONED_NAMESPACE                                    \
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KseniyaTikhomirova wrote:

Makes sense, I will rename them to the following:
_LIBSYCL_BEGIN_UNVERSIONED_NAMESPACE_SYCL
_LIBSYCL_BEGIN_NAMESPACE_SYCL

Thank you.

https://github.com/llvm/llvm-project/pull/144372