[libclc] libclc: Add ep utility (PR #186047)

[Wenju He via cfe-commits]

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@@ -0,0 +1,391 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifdef __CLC_SCALAR
+
+#if __CLC_FPSIZE == 16
+#define CLC_EP_USE_FMA true
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wenju-he wrote:

prefix the macro with __

https://github.com/llvm/llvm-project/pull/186047