use int::Int; | |
use float::Float; | |
trait Pow: Float { | |
/// Returns `a` raised to the power `b` | |
fn pow(self, mut b: i32) -> Self { | |
let mut a = self; | |
let recip = b < 0; | |
let mut r = Self::ONE; | |
loop { | |
if (b & 1) != 0 { | |
r *= a; | |
} | |
b = b.aborting_div(2); | |
if b == 0 { | |
break; | |
} | |
a *= a; | |
} | |
if recip { | |
Self::ONE / r | |
} else { | |
r | |
} | |
} | |
} | |
impl Pow for f32 {} | |
impl Pow for f64 {} | |
intrinsics! { | |
pub extern "C" fn __powisf2(a: f32, b: i32) -> f32 { | |
a.pow(b) | |
} | |
pub extern "C" fn __powidf2(a: f64, b: i32) -> f64 { | |
a.pow(b) | |
} | |
} |