35 lines
690 B
Rust
35 lines
690 B
Rust
/// Returns `a` raised to the power `b`
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macro_rules! pow {
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($a: expr, $b: expr) => ({
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let (mut a, mut b) = ($a, $b);
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let recip = b < 0;
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let mut r = 1.0;
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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.checked_div(2).unwrap_or_else(|| ::abort());
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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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1.0 / 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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intrinsics! {
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pub extern "C" fn __powisf2(a: f32, b: i32) -> f32 {
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pow!(a, b)
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}
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pub extern "C" fn __powidf2(a: f64, b: i32) -> f64 {
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pow!(a, b)
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}
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}
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