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const FP_ILOGBNAN: i32 = -1 - 0x7fffffff;
const FP_ILOGB0: i32 = FP_ILOGBNAN;
pub fn ilogbf(x: f32) -> i32 {
let mut i = x.to_bits();
let e = ((i >> 23) & 0xff) as i32;
if e == 0 {
i <<= 9;
if i == 0 {
force_eval!(0.0 / 0.0);
return FP_ILOGB0;
}
let mut e = -0x7f;
while (i >> 31) == 0 {
e -= 1;
i <<= 1;
}
e
} else if e == 0xff {
force_eval!(0.0 / 0.0);
if (i << 9) != 0 {
FP_ILOGBNAN
} else {
i32::max_value()
}
} else {
e - 0x7f
}
}