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#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
pub fn fmax(x: f64, y: f64) -> f64 {
// IEEE754 says: maxNum(x, y) is the canonicalized number y if x < y, x if y < x, the
// canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
// is either x or y, canonicalized (this means results might differ among implementations).
// When either x or y is a signalingNaN, then the result is according to 6.2.
//
// Since we do not support sNaN in Rust yet, we do not need to handle them.
// FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
// multiplying by 1.0. Should switch to the `canonicalize` when it works.
(if x.is_nan() || x < y { y } else { x }) * 1.0
}