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; | |
} | |
/* subnormal x */ | |
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 | |
} | |
} |