Remove extra::par fixes #5626

Author: Nick Desaulniers

src/libextra/par.rs

@@ -100,7 +100,6 @@ pub mod tempfile;
 pub mod term;
 pub mod time;
 pub mod arena;
-pub mod par;
 pub mod base64;
 pub mod rl;
 pub mod workcache;

src/libextra/std.rc

@@ -20,7 +20,6 @@ extern mod extra;
 use extra::arc;
 use extra::time;
 use extra::deque::Deque;
-use extra::par;
 use std::hashmap::HashSet;
 use std::int::abs;
 use std::io;
@@ -34,6 +33,144 @@ type node_id = i64;
 type graph = ~[~[node_id]];
 type bfs_result = ~[node_id];
 
+// Moved from extra::par
+mod par {
+    use std::cast;
+    use std::ptr;
+    use std::sys;
+    use std::uint;
+    use std::vec;
+    use extra::future;
+
+    /**
+     * The maximum number of tasks this module will spawn for a single
+     * operation.
+     */
+    static max_tasks : uint = 32u;
+
+    /// The minimum number of elements each task will process.
+    static min_granularity : uint = 1024u;
+
+    /**
+     * An internal helper to map a function over a large vector and
+     * return the intermediate results.
+     *
+     * This is used to build most of the other parallel vector functions,
+     * like map or alli.
+     */
+    fn map_slices<A:Copy + Owned,B:Copy + Owned>(
+        xs: &[A],
+        f: &fn() -> ~fn(uint, v: &[A]) -> B)
+        -> ~[B] {
+
+        let len = xs.len();
+        if len < min_granularity {
+            info!("small slice");
+            // This is a small vector, fall back on the normal map.
+            ~[f()(0u, xs)]
+        }
+        else {
+            let num_tasks = uint::min(max_tasks, len / min_granularity);
+
+            let items_per_task = len / num_tasks;
+
+            let mut futures = ~[];
+            let mut base = 0u;
+            info!("spawning tasks");
+            while base < len {
+                let end = uint::min(len, base + items_per_task);
+                do vec::as_imm_buf(xs) |p, _len| {
+                    let f = f();
+                    let base = base;
+                    let f = do future::spawn() || {
+                        unsafe {
+                            let len = end - base;
+                            let slice = (ptr::offset(p, base),
+                                         len * sys::size_of::<A>());
+                            info!("pre-slice: %?", (base, slice));
+                            let slice : &[A] =
+                                cast::transmute(slice);
+                            info!("slice: %?", (base, slice.len(), end - base));
+                            assert_eq!(slice.len(), end - base);
+                            f(base, slice)
+                        }
+                    };
+                    futures.push(f);
+                };
+                base += items_per_task;
+            }
+            info!("tasks spawned");
+
+            info!("num_tasks: %?", (num_tasks, futures.len()));
+            assert_eq!(num_tasks, futures.len());
+
+            let r = do vec::map_consume(futures) |ys| {
+                let mut ys = ys;
+                ys.get()
+            };
+            r
+        }
+    }
+
+    /// A parallel version of map.
+    pub fn map<A:Copy + Owned,B:Copy + Owned>(
+        xs: &[A], fn_factory: &fn() -> ~fn(&A) -> B) -> ~[B] {
+        vec::concat(map_slices(xs, || {
+            let f = fn_factory();
+            let result: ~fn(uint, &[A]) -> ~[B] =
+                |_, slice| vec::map(slice, |x| f(x));
+            result
+        }))
+    }
+
+    /// A parallel version of mapi.
+    pub fn mapi<A:Copy + Owned,B:Copy + Owned>(
+            xs: &[A],
+            fn_factory: &fn() -> ~fn(uint, &A) -> B) -> ~[B] {
+        let slices = map_slices(xs, || {
+            let f = fn_factory();
+            let result: ~fn(uint, &[A]) -> ~[B] = |base, slice| {
+                vec::mapi(slice, |i, x| {
+                    f(i + base, x)
+                })
+            };
+            result
+        });
+        let r = vec::concat(slices);
+        info!("%?", (r.len(), xs.len()));
+        assert_eq!(r.len(), xs.len());
+        r
+    }
+
+    /// Returns true if the function holds for all elements in the vector.
+    pub fn alli<A:Copy + Owned>(
+        xs: &[A],
+        fn_factory: &fn() -> ~fn(uint, &A) -> bool) -> bool
+    {
+        do vec::all(map_slices(xs, || {
+            let f = fn_factory();
+            let result: ~fn(uint, &[A]) -> bool = |base, slice| {
+                vec::alli(slice, |i, x| {
+                    f(i + base, x)
+                })
+            };
+            result
+        })) |x| { *x }
+    }
+
+    /// Returns true if the function holds for any elements in the vector.
+    pub fn any<A:Copy + Owned>(
+        xs: &[A],
+        fn_factory: &fn() -> ~fn(&A) -> bool) -> bool {
+        do vec::any(map_slices(xs, || {
+            let f = fn_factory();
+            let result: ~fn(uint, &[A]) -> bool =
+                |_, slice| vec::any(slice, |x| f(x));
+            result
+        })) |x| { *x }
+    }
+}
+
 fn make_edges(scale: uint, edgefactor: uint) -> ~[(node_id, node_id)] {
     let mut r = rand::XorShiftRng::new();