[libc-commits] [libc] [libc][math][c23] add c23 floating point fmaximum and fminimum functions. (PR #86016)

[via libc-commits]

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@@ -58,6 +58,102 @@ LIBC_INLINE T fmax(T x, T y) {
   }
 }
 
+template <typename T, cpp::enable_if_t<cpp::is_floating_point_v<T>, int> = 0>
+LIBC_INLINE T fmaximum(T x, T y) {
+  FPBits<T> bitx(x), bity(y);
+
+  if (bitx.is_nan())
+    return x;
+  if (bity.is_nan())
+    return y;
+  if (bitx.sign() != bity.sign())
+    return (bitx.is_neg() ? y : x);
+  return x > y ? x : y;
+}
+
+template <typename T, cpp::enable_if_t<cpp::is_floating_point_v<T>, int> = 0>
+LIBC_INLINE T fminimum(T x, T y) {
+  const FPBits<T> bitx(x), bity(y);
+
+  if (bitx.is_nan())
+    return x;
+  if (bity.is_nan())
+    return y;
+  if (bitx.sign() != bity.sign())
+    return (bitx.is_neg()) ? x : y;
+  return x < y ? x : y;
+}
+
+template <typename T, cpp::enable_if_t<cpp::is_floating_point_v<T>, int> = 0>
+LIBC_INLINE T fmaximum_num(T x, T y) {
+  FPBits<T> bitx(x), bity(y);
+
+  if (bitx.is_nan())
----------------
lntue wrote:

Something like `EXPECT_FP_EQ_WITH_EXCEPTION(aNaN, func(aNaN, sNaN), FE_INVALID);` should work.  And you'll neet to test with all combinations of NaNs.

https://github.com/llvm/llvm-project/pull/86016