[libclc] [NFC][libclc] Refactor _CLC_*_VECTORIZE macros to functions in .inc files (PR #145678)

[Fraser Cormack via cfe-commits]

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@@ -0,0 +1,121 @@
+//===----------------------------------------------------------------------===//
+//
+// 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/utils.h>
+
+#if __CLC_VECSIZE_OR_1 == 1
+
+#ifndef __IMPL_FUNCTION
+#define __IMPL_FUNCTION FUNCTION
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frasercrmck wrote:

Should we be `#undef`ing these macros at the end of this file?

https://github.com/llvm/llvm-project/pull/145678