const LG3: f32 = 0.28498786688; /* 0x91e9ee.0p-25 */
const LG4: f32 = 0.24279078841; /* 0xf89e26.0p-26 */
-#[inline]
#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
pub fn logf(mut x: f32) -> f32 {
let x1p25 = f32::from_bits(0x4c000000); // 0x1p25f === 2 ^ 25