Showing the size of types in Rust.

gistfile1.txt

use std::mem::size_of;

type TigerInt = i32;
type Label = usize;
type Temp = usize;

#[derive(Debug)]
pub enum IrExp {
    Const(TigerInt),
    Name(Label),
    Temp(Temp),
    Binop(IrBinop, Box<IrExp>, Box<IrExp>),
    Mem(Box<IrExp>),
    Call(Box<IrExp>, Vec<IrExp>),
    Eseq(Box<IrStm>, Box<IrExp>),
}

#[derive(Debug)]
pub enum IrStm {
    Move(IrExp, IrExp),
    Exp(IrExp),
    Jump(IrExp, Vec<Label>),
    Cjump(IrRelop, IrExp, IrExp, Label, Label),
    Seq(Box<IrStm>, Box<IrStm>),
    Label(Label),
}

#[derive(Debug)]
pub enum IrBinop {
    Plus,
    Minus,
    Mul,
    Div,
    And,
    Or,
    Lshift,
    Rshift,
    ArShift,
    Xor,
}

#[derive(Debug)]
pub enum IrRelop {
    Eq,
    Ne,
    Lt,
    Gt,
    Le,
    Ge,
    Ult,
    Ule,
    Ugt,
    Uge,
}


macro_rules! show_size {
    (header) => (
        println!("{:<28} {:>4}    {}", "Type", "T", "Option<T>");
    );
    ($t:ty) => (
        println!("{:<28} {:4} {:4}", stringify!($t), size_of::<$t>(), size_of::<Option<$t>>())
    )
}

fn main() {
    show_size!(header);
    show_size!(IrExp);
    show_size!(IrStm);
    show_size!(IrRelop);
    show_size!(Option<bool>);
    show_size!(Option<Option<bool>>);
    show_size!(Option<Option<Option<bool>>>);
}