Function peek

crates/vm/src/builtins/frame.rs:76–79

(stack: i64, n: u32)

    }

    fn peek(stack: i64, n: u32) -> i64 {
        debug_assert!(n >= 1);
        (stack >> (BITS_PER_BLOCK * (n - 1))) & MASK
    }

    fn stack_swap(stack: i64, n: u32) -> i64 {
        debug_assert!(n >= 1);