fastrange-rs 0.1.0

A fast alternative to the modulo reduction ported to Rust
Documentation 
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#![no_std]

/// Given a value "word", produces an integer in [0,p) without division.
#[inline(always)]
pub fn fastrange_32(word: u32, p: u32) -> u32 {
    ((u64::from(word) * u64::from(p)) >> 32) as u32
}

/// Given a value "word", produces an integer in [0,p) without division.
#[inline(always)]
pub fn fastrange_64(word: u64, p: u64) -> u64 {
    ((word as u128 * p as u128) >> 64) as u64
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_32() {
        for x in 0..1_000_000 {
            assert!(fastrange_32(x, 5) < 5);
        }
    }

    #[test]
    fn test_64() {
        for x in 0..1_000_000 {
            assert!(fastrange_64(x, 5) < 5);
        }
    }
}