[libclc] [libclc] Declare workitem built-ins in clc, move ptx-nvidiacl workitem built-ins into clc (PR #144333)

[Fraser Cormack via cfe-commits]

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@@ -0,0 +1,16 @@
+//===----------------------------------------------------------------------===//
+//
+// 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_WORKITEM_CLC_GET_ENQUEUED_LOCAL_SIZE_H__
+#define __CLC_WORKITEM_CLC_GET_ENQUEUED_LOCAL_SIZE_H__
+
+#include <clc/internal/clc.h>
+
+_CLC_OVERLOAD _CLC_DECL size_t clc_get_enqueued_local_size(uint dim);
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frasercrmck wrote:

Should this (and the rest) be prefixed with `__`? Like `__clc_get_enqueued_local_size`?

https://github.com/llvm/llvm-project/pull/144333