[libclc] libclc: Replace nextafter implementation (PR #186082)

[Romaric Jodin via cfe-commits]

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@@ -0,0 +1,17 @@
+//===----------------------------------------------------------------------===//
+//
+// 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_CONST _CLC_DEF __CLC_GENTYPE
+__clc_nextdown(__CLC_GENTYPE x) {
+  __CLC_S_GENTYPE increment =
+      x > __CLC_FP_LIT(0.0) ? (__CLC_S_GENTYPE)-1 : (__CLC_S_GENTYPE)1;
+  __CLC_S_GENTYPE ix = __CLC_AS_S_GENTYPE(x) + increment;
+  __CLC_GENTYPE y =
+      x == __CLC_FP_LIT(0.0) ? -__CLC_GENTYPE_TRUE_MIN : __CLC_AS_GENTYPE(ix);
----------------
rjodinchr wrote:

yes

https://github.com/llvm/llvm-project/pull/186082