pub fn count_non_ascii_sse2(buffer: &[u8]) -> u64 {
    let mut count = 0;
    let (prefix, simd, suffix) = unsafe { buffer.align_to::<core::arch::x86_64::__m128i>() };
    for &b in prefix {
        if b >= 0x80 {
            count += 1;
        }
    }
    for &s in simd {
        count += unsafe {core::arch::x86_64::_mm_movemask_epi8(s)}.count_ones() as u64;
    }
    for &b in suffix {
        if b >= 0x80 {
            count += 1;
        }
    }
    count
}