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use core::f32;
#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
pub fn truncf(x: f32) -> f32 {
// On wasm32 we know that LLVM's intrinsic will compile to an optimized
// `f32.trunc` native instruction, so we can leverage this for both code size
// and speed.
llvm_intrinsically_optimized! {
#[cfg(target_arch = "wasm32")] {
return unsafe { ::core::intrinsics::truncf32(x) }
}
}
let x1p120 = f32::from_bits(0x7b800000); // 0x1p120f === 2 ^ 120
let mut i: u32 = x.to_bits();
let mut e: i32 = (i >> 23 & 0xff) as i32 - 0x7f + 9;
let m: u32;
if e >= 23 + 9 {
return x;
}
if e < 9 {
e = 1;
}
m = -1i32 as u32 >> e;
if (i & m) == 0 {
return x;
}
force_eval!(x + x1p120);
i &= !m;
f32::from_bits(i)
}
#[cfg(not(target_arch = "powerpc64"))]
#[cfg(test)]
mod tests {
#[test]
fn sanity_check() {
assert_eq!(super::truncf(1.1), 1.0);
}
}