1 files changed, 41 insertions, 0 deletions
diff --git a/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h b/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h
new file mode 100644
index 000000000000..ea2210a4a7ad
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKEND_BACKEND_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKEND_BACKEND_H
+
+#include <__config>
+#include <cstddef>
+
+#if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL)
+#  include <__algorithm/pstl_backends/cpu_backends/serial.h>
+#elif defined(_LIBCPP_PSTL_CPU_BACKEND_THREAD)
+#  include <__algorithm/pstl_backends/cpu_backends/thread.h>
+#elif defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
+#  include <__algorithm/pstl_backends/cpu_backends/libdispatch.h>
+#else
+#  error "Invalid CPU backend choice"
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __cpu_backend_tag {};
+
+inline constexpr size_t __lane_size = 64;
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKEND_BACKEND_H