[libclc] [libclc] Move minmag & maxmag to the CLC library (PR #137982)

[Matt Arsenault via cfe-commits]

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@@ -0,0 +1,18 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_maxmag(__CLC_GENTYPE x,
+                                                  __CLC_GENTYPE y) {
+  const __CLC_GENTYPE res = __clc_select(
+      y, x,
+      __CLC_CONVERT_BIT_INTN(__clc_isgreater(__clc_fabs(x), __clc_fabs(y))));
+  return __clc_select(
+      res, __clc_fmax(x, y),
+      __CLC_CONVERT_BIT_INTN(__clc_isnan(x) || __clc_isnan(y) ||
+                             __clc_isequal(__clc_fabs(x), __clc_fabs(y))));
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arsenm wrote:

This can just use ternary operator, I don't see what the select is adding other than complexity 

https://github.com/llvm/llvm-project/pull/137982