[libc-commits] [libc] [libc][math][c23] Implement canonicalize functions (PR #85940)

[via libc-commits]

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@@ -73,6 +76,54 @@ LIBC_INLINE T fdim(T x, T y) {
   return (x > y ? x - y : 0);
 }
 
+template <typename T, cpp::enable_if_t<cpp::is_floating_point_v<T>, int> = 0>
+LIBC_INLINE int canonicalize(T &cx, const T &x) {
+  FPBits<T> sx(x);
+  if (LIBC_UNLIKELY(sx.is_signaling_nan())) {
+    cx = FPBits<T>::quiet_nan(sx.sign(), sx.get_explicit_mantissa()).get_val();
+    raise_except_if_required(FE_INVALID);
+    return 1;
+  } else if constexpr (get_fp_type<T>() == FPType::X86_Binary80) {
----------------
lntue wrote:

since you already have early return, just remove the `else`, making it:
```
if (LIBC_UNLIKELY(sx.is_signaling_nan()) {
}

if constexpr (get_fp_type<T>() != FPType::X86_Binary80) {
  cx = x;
  return 0;
}

// x86-extended precision
...
```

https://github.com/llvm/llvm-project/pull/85940