#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]

pub fn rintf(x: f32) -> f32 {

    let one_over_e = 1.0 / f32::EPSILON;

    let as_u32: u32 = x.to_bits();

    let exponent: u32 = as_u32 >> 23 & 0xff;

    let is_positive = (as_u32 >> 31) == 0;

    if exponent >= 0x7f + 23 {

        x

    } else {

        let ans = if is_positive {

            #[cfg(all(target_arch = "x86", not(target_feature = "sse2")))]

            let x = force_eval!(x);

            let xplusoneovere = x + one_over_e;

            #[cfg(all(target_arch = "x86", not(target_feature = "sse2")))]

            let xplusoneovere = force_eval!(xplusoneovere);

            xplusoneovere - one_over_e

        } else {

            #[cfg(all(target_arch = "x86", not(target_feature = "sse2")))]

            let x = force_eval!(x);

            let xminusoneovere = x - one_over_e;

            #[cfg(all(target_arch = "x86", not(target_feature = "sse2")))]

            let xminusoneovere = force_eval!(xminusoneovere);

            xminusoneovere + one_over_e

        };

        if ans == 0.0 { if is_positive { 0.0 } else { -0.0 } } else { ans }

    }

}

// PowerPC tests are failing on LLVM 13: https://github.com/rust-lang/rust/issues/88520

#[cfg(not(target_arch = "powerpc64"))]

#[cfg(test)]

mod tests {

    use super::rintf;

    #[test]

    fn negative_zero() {

        assert_eq!(rintf(-0.0_f32).to_bits(), (-0.0_f32).to_bits());

    }

    #[test]

    fn sanity_check() {

        assert_eq!(rintf(-1.0), -1.0);

        assert_eq!(rintf(2.8), 3.0);

        assert_eq!(rintf(-0.5), -0.0);

        assert_eq!(rintf(0.5), 0.0);

        assert_eq!(rintf(-1.5), -2.0);

        assert_eq!(rintf(1.5), 2.0);

    }

}