Rollup of 14 pull requests

Cargo.lock

@@ -2624,6 +2624,7 @@ dependencies = [
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "memmap 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 1.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc 0.0.0",
  "rustc-demangle 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_allocator 0.0.0",

appveyor.yml

@@ -5,11 +5,6 @@ environment:
   # server goes down presumably. See #43333 for more info
   CARGO_HTTP_CHECK_REVOKE: false
 
-  # Execute the builds on GCE instead of Hyper-V. Those builders have a 3-4
-  # minute startup overhead, but AppVeyor support recommended this as a
-  # possible solution for #58160 (spurious 259 exit codes)
-  appveyor_build_worker_cloud: gce
-
   matrix:
   # 32/64 bit MSVC tests
   - MSYS_BITS: 64

src/liballoc/vec.rs

@@ -1260,7 +1260,7 @@ impl<T> Vec<T> {
     /// This method uses a closure to create new values on every push. If
     /// you'd rather [`Clone`] a given value, use [`resize`]. If you want
     /// to use the [`Default`] trait to generate values, you can pass
-    /// [`Default::default()`] as the second argument..
+    /// [`Default::default()`] as the second argument.
     ///
     /// # Examples
     ///

src/libcore/benches/iter.rs

@@ -185,13 +185,13 @@ bench_sums! {
 bench_sums! {
     bench_filter_sum,
     bench_filter_ref_sum,
-    (0i64..1000000).filter(|x| x % 2 == 0)
+    (0i64..1000000).filter(|x| x % 3 == 0)
 }
 
 bench_sums! {
     bench_filter_chain_sum,
     bench_filter_chain_ref_sum,
-    (0i64..1000000).chain(0..1000000).filter(|x| x % 2 == 0)
+    (0i64..1000000).chain(0..1000000).filter(|x| x % 3 == 0)
 }
 
 bench_sums! {
@@ -306,3 +306,31 @@ fn bench_skip_then_zip(b: &mut Bencher) {
         assert_eq!(s, 2009900);
     });
 }
+
+#[bench]
+fn bench_filter_count(b: &mut Bencher) {
+    b.iter(|| {
+        (0i64..1000000).map(black_box).filter(|x| x % 3 == 0).count()
+    })
+}
+
+#[bench]
+fn bench_filter_ref_count(b: &mut Bencher) {
+    b.iter(|| {
+        (0i64..1000000).map(black_box).by_ref().filter(|x| x % 3 == 0).count()
+    })
+}
+
+#[bench]
+fn bench_filter_chain_count(b: &mut Bencher) {
+    b.iter(|| {
+        (0i64..1000000).chain(0..1000000).map(black_box).filter(|x| x % 3 == 0).count()
+    })
+}
+
+#[bench]
+fn bench_filter_chain_ref_count(b: &mut Bencher) {
+    b.iter(|| {
+        (0i64..1000000).chain(0..1000000).map(black_box).by_ref().filter(|x| x % 3 == 0).count()
+    })
+}

src/libcore/iter/adapters/mod.rs

@@ -681,12 +681,7 @@ impl<I: Iterator, P> Iterator for Filter<I, P> where P: FnMut(&I::Item) -> bool
 
     #[inline]
     fn next(&mut self) -> Option<I::Item> {
-        for x in &mut self.iter {
-            if (self.predicate)(&x) {
-                return Some(x);
-            }
-        }
-        None
+        self.try_for_each(Err).err()
     }
 
     #[inline]
@@ -707,12 +702,9 @@ impl<I: Iterator, P> Iterator for Filter<I, P> where P: FnMut(&I::Item) -> bool
     // Using the branchless version will also simplify the LLVM byte code, thus
     // leaving more budget for LLVM optimizations.
     #[inline]
-    fn count(mut self) -> usize {
-        let mut count = 0;
-        for x in &mut self.iter {
-            count += (self.predicate)(&x) as usize;
-        }
-        count
+    fn count(self) -> usize {
+        let mut predicate = self.predicate;
+        self.iter.map(|x| predicate(&x) as usize).sum()
     }
 
     #[inline]
@@ -746,12 +738,7 @@ impl<I: DoubleEndedIterator, P> DoubleEndedIterator for Filter<I, P>
 {
     #[inline]
     fn next_back(&mut self) -> Option<I::Item> {
-        for x in self.iter.by_ref().rev() {
-            if (self.predicate)(&x) {
-                return Some(x);
-            }
-        }
-        None
+        self.try_rfold((), |_, x| Err(x)).err()
     }
 
     #[inline]
@@ -820,12 +807,7 @@ impl<B, I: Iterator, F> Iterator for FilterMap<I, F>
 
     #[inline]
     fn next(&mut self) -> Option<B> {
-        for x in self.iter.by_ref() {
-            if let Some(y) = (self.f)(x) {
-                return Some(y);
-            }
-        }
-        None
+        self.try_for_each(Err).err()
     }
 
     #[inline]
@@ -863,12 +845,7 @@ impl<B, I: DoubleEndedIterator, F> DoubleEndedIterator for FilterMap<I, F>
 {
     #[inline]
     fn next_back(&mut self) -> Option<B> {
-        for x in self.iter.by_ref().rev() {
-            if let Some(y) = (self.f)(x) {
-                return Some(y);
-            }
-        }
-        None
+        self.try_rfold((), |_, x| Err(x)).err()
     }
 
     #[inline]

src/libcore/mem.rs

@@ -900,10 +900,16 @@ pub fn discriminant<T>(v: &T) -> Discriminant<T> {
     }
 }
 
+// FIXME: Reference `MaybeUninit` from these docs, once that is stable.
 /// A wrapper to inhibit compiler from automatically calling `T`’s destructor.
 ///
 /// This wrapper is 0-cost.
 ///
+/// `ManuallyDrop<T>` is subject to the same layout optimizations as `T`.
+/// As a consequence, it has *no effect* on the assumptions that the compiler makes
+/// about all values being initialized at their type.  In particular, initializing
+/// a `ManuallyDrop<&mut T>` with [`mem::zeroed`] is undefined behavior.
+///
 /// # Examples
 ///
 /// This wrapper helps with explicitly documenting the drop order dependencies between fields of
@@ -935,6 +941,8 @@ pub fn discriminant<T>(v: &T) -> Discriminant<T> {
 ///     }
 /// }
 /// ```
+///
+/// [`mem::zeroed`]: fn.zeroed.html
 #[stable(feature = "manually_drop", since = "1.20.0")]
 #[lang = "manually_drop"]
 #[derive(Copy, Clone, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]

src/libcore/pin.rs

@@ -215,7 +215,7 @@
 //!     had a method `fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut T>`.
 //!     Then we could do the following:
 //!     ```compile_fail
-//!     fn exploit_ref_cell<T>(rc: Pin<&mut RefCell<T>) {
+//!     fn exploit_ref_cell<T>(rc: Pin<&mut RefCell<T>>) {
 //!         { let p = rc.as_mut().get_pin_mut(); } // Here we get pinned access to the `T`.
 //!         let rc_shr: &RefCell<T> = rc.into_ref().get_ref();
 //!         let b = rc_shr.borrow_mut();

src/libcore/str/mod.rs

@@ -3965,7 +3965,7 @@ impl str {
         me.make_ascii_lowercase()
     }
 
-    /// Return an iterator that escapes each char in `s` with [`char::escape_debug`].
+    /// Return an iterator that escapes each char in `self` with [`char::escape_debug`].
     ///
     /// Note: only extended grapheme codepoints that begin the string will be
     /// escaped.
@@ -4013,7 +4013,7 @@ impl str {
         }
     }
 
-    /// Return an iterator that escapes each char in `s` with [`char::escape_default`].
+    /// Return an iterator that escapes each char in `self` with [`char::escape_default`].
     ///
     /// [`char::escape_default`]: ../std/primitive.char.html#method.escape_default
     ///
@@ -4051,7 +4051,7 @@ impl str {
         EscapeDefault { inner: self.chars().flat_map(CharEscapeDefault) }
     }
 
-    /// Return an iterator that escapes each char in `s` with [`char::escape_unicode`].
+    /// Return an iterator that escapes each char in `self` with [`char::escape_unicode`].
     ///
     /// [`char::escape_unicode`]: ../std/primitive.char.html#method.escape_unicode
     ///

src/librustc/lint/mod.rs

@@ -132,14 +132,22 @@ macro_rules! declare_lint {
 
 #[macro_export]
 macro_rules! declare_tool_lint {
-    ($vis: vis $tool: ident ::$NAME: ident, $Level: ident, $desc: expr) => (
-        declare_tool_lint!{$vis $tool::$NAME, $Level, $desc, false}
+    (
+        $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level: ident, $desc: expr
+    ) => (
+        declare_tool_lint!{$(#[$attr])* $vis $tool::$NAME, $Level, $desc, false}
     );
-    ($vis: vis $tool: ident ::$NAME: ident, $Level: ident, $desc: expr,
-     report_in_external_macro: $rep: expr) => (
-         declare_tool_lint!{$vis $tool::$NAME, $Level, $desc, $rep}
+    (
+        $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level:ident, $desc:expr,
+        report_in_external_macro: $rep:expr
+    ) => (
+         declare_tool_lint!{$(#[$attr])* $vis $tool::$NAME, $Level, $desc, $rep}
     );
-    ($vis: vis $tool: ident ::$NAME: ident, $Level: ident, $desc: expr, $external: expr) => (
+    (
+        $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level:ident, $desc:expr,
+        $external:expr
+    ) => (
+        $(#[$attr])*
         $vis static $NAME: &$crate::lint::Lint = &$crate::lint::Lint {
             name: &concat!(stringify!($tool), "::", stringify!($NAME)),
             default_level: $crate::lint::$Level,

src/librustc/session/config.rs

@@ -1405,9 +1405,7 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
     crate_attr: Vec<String> = (Vec::new(), parse_string_push, [TRACKED],
         "inject the given attribute in the crate"),
     self_profile: bool = (false, parse_bool, [UNTRACKED],
-        "run the self profiler"),
-    profile_json: bool = (false, parse_bool, [UNTRACKED],
-        "output a json file with profiler results"),
+        "run the self profiler and output the raw event data"),
     emit_stack_sizes: bool = (false, parse_bool, [UNTRACKED],
         "emits a section containing stack size metadata"),
     plt: Option<bool> = (None, parse_opt_bool, [TRACKED],

src/librustc/session/mod.rs

@@ -44,7 +44,9 @@ use std::fmt;
 use std::io::Write;
 use std::path::PathBuf;
 use std::time::Duration;
-use std::sync::mpsc;
+use std::sync::{Arc, mpsc};
+
+use parking_lot::Mutex as PlMutex;
 
 mod code_stats;
 pub mod config;
@@ -127,11 +129,8 @@ pub struct Session {
     /// Used by `-Z profile-queries` in `util::common`.
     pub profile_channel: Lock<Option<mpsc::Sender<ProfileQueriesMsg>>>,
 
-    /// Used by `-Z self-profile`.
-    pub self_profiling_active: bool,
-
-    /// Used by `-Z self-profile`.
-    pub self_profiling: Lock<SelfProfiler>,
+    /// Used by -Z self-profile
+    pub self_profiling: Option<Arc<PlMutex<SelfProfiler>>>,
 
     /// Some measurements that are being gathered during compilation.
     pub perf_stats: PerfStats,
@@ -834,27 +833,23 @@ impl Session {
     #[inline(never)]
     #[cold]
     fn profiler_active<F: FnOnce(&mut SelfProfiler) -> ()>(&self, f: F) {
-        let mut profiler = self.self_profiling.borrow_mut();
-        f(&mut profiler);
+        match &self.self_profiling {
+            None => bug!("profiler_active() called but there was no profiler active"),
+            Some(profiler) => {
+                let mut p = profiler.lock();
+
+                f(&mut p);
+            }
+        }
     }
 
     #[inline(always)]
     pub fn profiler<F: FnOnce(&mut SelfProfiler) -> ()>(&self, f: F) {
-        if unlikely!(self.self_profiling_active) {
+        if unlikely!(self.self_profiling.is_some()) {
             self.profiler_active(f)
         }
     }
 
-    pub fn print_profiler_results(&self) {
-        let mut profiler = self.self_profiling.borrow_mut();
-        profiler.print_results(&self.opts);
-    }
-
-    pub fn save_json_results(&self) {
-        let profiler = self.self_profiling.borrow();
-        profiler.save_results(&self.opts);
-    }
-
     pub fn print_perf_stats(&self) {
         println!(
             "Total time spent computing symbol hashes:      {}",
@@ -1136,6 +1131,10 @@ pub fn build_session_(
     source_map: Lrc<source_map::SourceMap>,
     driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
 ) -> Session {
+    let self_profiler =
+        if sopts.debugging_opts.self_profile { Some(Arc::new(PlMutex::new(SelfProfiler::new()))) }
+        else { None };
+
     let host_triple = TargetTriple::from_triple(config::host_triple());
     let host = Target::search(&host_triple).unwrap_or_else(|e|
         span_diagnostic
@@ -1185,9 +1184,6 @@ pub fn build_session_(
         CguReuseTracker::new_disabled()
     };
 
-    let self_profiling_active = sopts.debugging_opts.self_profile ||
-                                sopts.debugging_opts.profile_json;
-
     let sess = Session {
         target: target_cfg,
         host,
@@ -1216,8 +1212,7 @@ pub fn build_session_(
         imported_macro_spans: OneThread::new(RefCell::new(FxHashMap::default())),
         incr_comp_session: OneThread::new(RefCell::new(IncrCompSession::NotInitialized)),
         cgu_reuse_tracker,
-        self_profiling_active,
-        self_profiling: Lock::new(SelfProfiler::new()),
+        self_profiling: self_profiler,
         profile_channel: Lock::new(None),
         perf_stats: PerfStats {
             symbol_hash_time: Lock::new(Duration::from_secs(0)),