[libclc] libclc: Add sub_group_reduce_* functions (PR #185294)

[Wenju He via cfe-commits]

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@@ -0,0 +1,15 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "clc/synchronization/clc_sub_group_reduce.h"
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wenju-he wrote:

clc/subgroup/clc_sub_group_reduce.h

https://github.com/llvm/llvm-project/pull/185294