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