1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
|
// 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(unsafe_destructor, box_syntax)]
use std::env;
use std::thread::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: int, depth: int) {
for _ in 0..repeat {
let dur = Duration::span(|| {
let _ = Thread::scoped(move|| {
recurse_or_panic(depth, None)
}).join();
});
println!("iter: {}", dur);
}
}
// FIXME(#21721) used to be `List<()>` but that can cause
// certain LLVM versions to abort during optimizations.
type nillist = List<[u8; 0]>;
// Filled with things that have to be unwound
struct State {
unique: Box<nillist>,
vec: Vec<Box<nillist>>,
res: r
}
struct r {
_l: Box<nillist>,
}
#[unsafe_destructor]
impl Drop for r {
fn drop(&mut self) {}
}
fn r(l: Box<nillist>) -> r {
r {
_l: l
}
}
fn recurse_or_panic(depth: int, 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));
}
}
|
