31 lines
753 B
Rust
31 lines
753 B
Rust
macro_rules! pow {
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($intrinsic:ident: $fty:ty, $ity:ident) => {
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/// Returns `a` raised to the power `b`
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#[cfg_attr(not(test), no_mangle)]
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pub extern "C" fn $intrinsic(a: $fty, b: $ity) -> $fty {
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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: $fty = 1.0;
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loop {
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if (b & 1) != 0 {
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r *= a;
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}
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b = sdiv!($ity, b, 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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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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}
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pow!(__powisf2: f32, i32);
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pow!(__powidf2: f64, i32);
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