Function rs2

crates/virtual-machine/src/cpu/decoder.rs:877–879

(word: u32)

    field(word, 31, 25) as u8
}

// Sign-extend `val` (a value in the low `bits` bits) to `i64`.
fn sign_ext(val: u32, bits: u32) -> i64 {
    let shift = 32 - bits;
    ((val << shift) as i32 >> shift) as i64
}