[libcxx-commits] [libcxx] [libc++] Simplify std::strong_order (PR #164233)

[A. Jiang via libcxx-commits]

================
@@ -53,38 +52,21 @@ struct __fn {
   template <class _Tp, class _Up, class _Dp = decay_t<_Tp>>
     requires is_same_v<_Dp, decay_t<_Up>> && is_floating_point_v<_Dp>
   _LIBCPP_HIDE_FROM_ABI static constexpr strong_ordering __go(_Tp&& __t, _Up&& __u, __priority_tag<1>) noexcept {
-    if constexpr (numeric_limits<_Dp>::is_iec559 && sizeof(_Dp) == sizeof(int32_t)) {
-      int32_t __rx = std::bit_cast<int32_t>(__t);
-      int32_t __ry = std::bit_cast<int32_t>(__u);
-      __rx         = (__rx < 0) ? (numeric_limits<int32_t>::min() - __rx - 1) : __rx;
-      __ry         = (__ry < 0) ? (numeric_limits<int32_t>::min() - __ry - 1) : __ry;
-      return (__rx <=> __ry);
-    } else if constexpr (numeric_limits<_Dp>::is_iec559 && sizeof(_Dp) == sizeof(int64_t)) {
-      int64_t __rx = std::bit_cast<int64_t>(__t);
-      int64_t __ry = std::bit_cast<int64_t>(__u);
-      __rx         = (__rx < 0) ? (numeric_limits<int64_t>::min() - __rx - 1) : __rx;
-      __ry         = (__ry < 0) ? (numeric_limits<int64_t>::min() - __ry - 1) : __ry;
+    if constexpr (numeric_limits<_Dp>::is_iec559 &&
+                  (sizeof(_Dp) == sizeof(int32_t) || sizeof(_Dp) == sizeof(int64_t))) {
+      using _IntT = conditional_t<sizeof(_Dp) == sizeof(int32_t), int32_t, int64_t>;
----------------
frederick-vs-ja wrote:

No change requested. Looks like that we can generalize this branch for other FP types later. (For `float{16,128}_t` and possibly `bfloat16_t`, but not Intel 80-bit `long double` or double-double format.)

https://github.com/llvm/llvm-project/pull/164233