1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 #![allow(non_camel_case_types)]
13 use std::cell::{RefCell, Cell};
14 use std::collections::HashMap;
15 use std::collections::hash_state::HashState;
16 use std::ffi::CString;
19 use std::iter::repeat;
21 use std::time::Duration;
25 use syntax::visit::Visitor;
27 // The name of the associated type for `Fn` return types
28 pub const FN_OUTPUT_NAME: &'static str = "Output";
30 // Useful type to use with `Result<>` indicate that an error has already
31 // been reported to the user, so no need to continue checking.
32 #[derive(Clone, Copy, Debug)]
33 pub struct ErrorReported;
35 pub fn time<T, U, F>(do_it: bool, what: &str, u: U, f: F) -> T where
38 thread_local!(static DEPTH: Cell<usize> = Cell::new(0));
39 if !do_it { return f(u); }
41 let old = DEPTH.with(|slot| {
51 Duration::span(move || {
57 // Hack up our own formatting for the duration to make it easier for scripts
58 // to parse (always use the same number of decimal places and the same unit).
59 const NANOS_PER_SEC: f64 = 1_000_000_000.0;
60 let secs = dur.secs() as f64;
61 let secs = secs + dur.extra_nanos() as f64 / NANOS_PER_SEC;
63 let mem_string = match get_resident() {
65 let mb = n as f64 / 1_000_000.0;
66 format!("; rss: {}MB", mb.round() as usize)
68 None => "".to_owned(),
70 println!("{}time: {:.3}{}\t{}", repeat(" ").take(old).collect::<String>(),
71 secs, mem_string, what);
73 DEPTH.with(|slot| slot.set(old));
79 fn get_resident() -> Option<usize> {
81 get_proc_self_statm_field(1)
87 // Like std::macros::try!, but for Option<>.
88 macro_rules! option_try(
89 ($e:expr) => (match $e { Some(e) => e, None => return None })
92 fn get_proc_self_statm_field(field: usize) -> Option<usize> {
98 let mut f = option_try!(File::open("/proc/self/statm").ok());
99 let mut contents = String::new();
100 option_try!(f.read_to_string(&mut contents).ok());
101 let s = option_try!(contents.split_whitespace().nth(field));
102 let npages = option_try!(s.parse::<usize>().ok());
103 Some(npages * ::std::env::page_size())
106 pub fn indent<R, F>(op: F) -> R where
110 // Use in conjunction with the log post-processor like `src/etc/indenter`
111 // to make debug output more readable.
114 debug!("<< (Result = {:?})", r);
118 pub struct Indenter {
119 _cannot_construct_outside_of_this_module: ()
122 impl Drop for Indenter {
123 fn drop(&mut self) { debug!("<<"); }
126 pub fn indenter() -> Indenter {
128 Indenter { _cannot_construct_outside_of_this_module: () }
131 struct LoopQueryVisitor<P> where P: FnMut(&ast::Expr_) -> bool {
136 impl<'v, P> Visitor<'v> for LoopQueryVisitor<P> where P: FnMut(&ast::Expr_) -> bool {
137 fn visit_expr(&mut self, e: &ast::Expr) {
138 self.flag |= (self.p)(&e.node);
140 // Skip inner loops, since a break in the inner loop isn't a
141 // break inside the outer loop
142 ast::ExprLoop(..) | ast::ExprWhile(..) => {}
143 _ => visit::walk_expr(self, e)
148 // Takes a predicate p, returns true iff p is true for any subexpressions
149 // of b -- skipping any inner loops (loop, while, loop_body)
150 pub fn loop_query<P>(b: &ast::Block, p: P) -> bool where P: FnMut(&ast::Expr_) -> bool {
151 let mut v = LoopQueryVisitor {
155 visit::walk_block(&mut v, b);
159 struct BlockQueryVisitor<P> where P: FnMut(&ast::Expr) -> bool {
164 impl<'v, P> Visitor<'v> for BlockQueryVisitor<P> where P: FnMut(&ast::Expr) -> bool {
165 fn visit_expr(&mut self, e: &ast::Expr) {
166 self.flag |= (self.p)(e);
167 visit::walk_expr(self, e)
171 // Takes a predicate p, returns true iff p is true for any subexpressions
172 // of b -- skipping any inner loops (loop, while, loop_body)
173 pub fn block_query<P>(b: &ast::Block, p: P) -> bool where P: FnMut(&ast::Expr) -> bool {
174 let mut v = BlockQueryVisitor {
178 visit::walk_block(&mut v, &*b);
182 /// K: Eq + Hash<S>, V, S, H: Hasher<S>
184 /// Determines whether there exists a path from `source` to `destination`. The
185 /// graph is defined by the `edges_map`, which maps from a node `S` to a list of
186 /// its adjacent nodes `T`.
188 /// Efficiency note: This is implemented in an inefficient way because it is
189 /// typically invoked on very small graphs. If the graphs become larger, a more
190 /// efficient graph representation and algorithm would probably be advised.
191 pub fn can_reach<T, S>(edges_map: &HashMap<T, Vec<T>, S>, source: T,
192 destination: T) -> bool
193 where S: HashState, T: Hash + Eq + Clone,
195 if source == destination {
199 // Do a little breadth-first-search here. The `queue` list
200 // doubles as a way to detect if we've seen a particular FR
201 // before. Note that we expect this graph to be an *extremely
203 let mut queue = vec!(source);
205 while i < queue.len() {
206 match edges_map.get(&queue[i]) {
208 for target in edges {
209 if *target == destination {
213 if !queue.iter().any(|x| x == target) {
214 queue.push((*target).clone());
225 /// Memoizes a one-argument closure using the given RefCell containing
226 /// a type implementing MutableMap to serve as a cache.
228 /// In the future the signature of this function is expected to be:
230 /// pub fn memoized<T: Clone, U: Clone, M: MutableMap<T, U>>(
231 /// cache: &RefCell<M>,
233 /// ) -> impl |T| -> U {
235 /// but currently it is not possible.
240 /// cache: RefCell<HashMap<usize, usize>>
243 /// fn factorial(ctxt: &Context, n: usize) -> usize {
244 /// memoized(&ctxt.cache, n, |n| match n {
246 /// _ => factorial(ctxt, n - 2) + factorial(ctxt, n - 1)
251 pub fn memoized<T, U, S, F>(cache: &RefCell<HashMap<T, U, S>>, arg: T, f: F) -> U
252 where T: Clone + Hash + Eq,
257 let key = arg.clone();
258 let result = cache.borrow().get(&key).cloned();
260 Some(result) => result,
263 cache.borrow_mut().insert(key, result.clone());
270 pub fn path2cstr(p: &Path) -> CString {
271 use std::os::unix::prelude::*;
273 let p: &OsStr = p.as_ref();
274 CString::new(p.as_bytes()).unwrap()
277 pub fn path2cstr(p: &Path) -> CString {
278 CString::new(p.to_str().unwrap()).unwrap()