[libclc] libclc: Update pow functions (PR #186890)

[Matt Arsenault via cfe-commits]

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@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+//
+// 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"
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arsenm wrote:

I was copying the generality from binary_def_scalarize.inc, the only difference here is supposed to be the use of loop instead of the manual scalarization. In the future I think the loop is better for code size. Ideally we would be able to compile the library with optsize but remove that for distribution 

https://github.com/llvm/llvm-project/pull/186890