| // Copyright 2012 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| #![feature(box_syntax, duration, duration_span, vec_push_all)] |
| |
| use std::env; |
| use std::thread; |
| use std::time::Duration; |
| |
| #[derive(Clone)] |
| enum List<T> { |
| Nil, Cons(T, Box<List<T>>) |
| } |
| |
| fn main() { |
| let (repeat, depth) = if env::var_os("RUST_BENCH").is_some() { |
| (50, 1000) |
| } else { |
| (10, 10) |
| }; |
| |
| run(repeat, depth); |
| } |
| |
| fn run(repeat: isize, depth: isize) { |
| for _ in 0..repeat { |
| let dur = Duration::span(|| { |
| let _ = thread::spawn(move|| { |
| recurse_or_panic(depth, None) |
| }).join(); |
| }); |
| println!("iter: {:?}", dur); |
| } |
| } |
| |
| type nillist = List<()>; |
| |
| // Filled with things that have to be unwound |
| |
| struct State { |
| unique: Box<nillist>, |
| vec: Vec<Box<nillist>>, |
| res: r |
| } |
| |
| struct r { |
| _l: Box<nillist>, |
| } |
| |
| impl Drop for r { |
| fn drop(&mut self) {} |
| } |
| |
| fn r(l: Box<nillist>) -> r { |
| r { |
| _l: l |
| } |
| } |
| |
| fn recurse_or_panic(depth: isize, st: Option<State>) { |
| if depth == 0 { |
| panic!(); |
| } else { |
| let depth = depth - 1; |
| |
| let st = match st { |
| None => { |
| State { |
| unique: box List::Nil, |
| vec: vec!(box List::Nil), |
| res: r(box List::Nil) |
| } |
| } |
| Some(st) => { |
| let mut v = st.vec.clone(); |
| v.push_all(&[box List::Cons((), st.vec.last().unwrap().clone())]); |
| State { |
| unique: box List::Cons((), box *st.unique), |
| vec: v, |
| res: r(box List::Cons((), st.res._l.clone())), |
| } |
| } |
| }; |
| |
| recurse_or_panic(depth, Some(st)); |
| } |
| } |