[libclc] [libclc] Add generic implementation of bitfield_insert/extract,bit_reverse (PR #149070)

[Fraser Cormack via cfe-commits]

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@@ -0,0 +1,21 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 __CLC_OPENCL_INTEGER_BIT_REVERSE_H__
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frasercrmck wrote:

I think these 4 OpenCL decls should also have  `#ifdef cl_khr_extended_bit_ops`.

https://github.com/llvm/llvm-project/pull/149070