vendor/libm-0.1.4/src/math/fabs.rs


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use core::u64;

/// Absolute value (magnitude) (f64)
/// Calculates the absolute value (magnitude) of the argument `x`,
/// by direct manipulation of the bit representation of `x`.
#[inline]
#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
pub fn fabs(x: f64) -> f64 {
    // On wasm32 we know that LLVM's intrinsic will compile to an optimized
    // `f64.abs` native instruction, so we can leverage this for both code size
    // and speed.
    llvm_intrinsically_optimized! {
        #[cfg(target_arch = "wasm32")] {
            return unsafe { ::core::intrinsics::fabsf64(x) }
        }
    }
    f64::from_bits(x.to_bits() & (u64::MAX / 2))
}