[libc-commits] [libc] [libc][math][c23] Add nextup{, f, f128} and nextdown{, f, f128} functions (PR #85431)

[via libc-commits]

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@@ -230,6 +230,27 @@ LIBC_INLINE T nextafter(T from, U to) {
   return from_bits.get_val();
 }
 
+template <typename T, cpp::enable_if_t<cpp::is_floating_point_v<T>, int> = 0>
+LIBC_INLINE T nextupdown(T x, Sign sign) {
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lntue wrote:

Use the second template parameter for the `sign`, and use `enable_if_t` on the return type instead.
Also mark this function `constexpr` if possible.

https://github.com/llvm/llvm-project/pull/85431