self-profiling: Update measureme to 0.4.0 and use new RAII-based API.

Cargo.lock

@@ -1954,9 +1954,9 @@ dependencies = [
 
 [[package]]
 name = "measureme"
-version = "0.3.0"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d09de7dafa3aa334bc806447c7e4de69419723312f4b88b80b561dea66601ce8"
+checksum = "cd21b0e6e1af976b269ce062038fe5e1b9ca2f817ab7a3af09ec4210aebf0d30"
 dependencies = [
  "byteorder",
  "memmap",

src/librustc/Cargo.toml

@@ -37,4 +37,4 @@ byteorder = { version = "1.3" }
 chalk-engine = { version = "0.9.0", default-features=false }
 rustc_fs_util = { path = "../librustc_fs_util" }
 smallvec = { version = "0.6.8", features = ["union", "may_dangle"] }
-measureme = "0.3"
+measureme = "0.4"

src/librustc/util/profiling.rs

@@ -14,9 +14,12 @@
 /// MmapSerializatioSink is faster on macOS and Linux
 /// but FileSerializationSink is faster on Windows
 #[cfg(not(windows))]
-type Profiler = measureme::Profiler<measureme::MmapSerializationSink>;
+type SerializationSink = measureme::MmapSerializationSink;
 #[cfg(windows)]
-type Profiler = measureme::Profiler<measureme::FileSerializationSink>;
+type SerializationSink = measureme::FileSerializationSink;
+
+type Profiler = measureme::Profiler<SerializationSink>;
+
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Ord, PartialOrd)]
 pub enum ProfileCategory {
@@ -298,14 +301,7 @@ pub fn register_query_name(&self, query_name: QueryName) {
 }
 
 #[must_use]
-pub struct TimingGuard<'a>(Option<TimingGuardInternal<'a>>);
-
-struct TimingGuardInternal<'a> {
-    raw_profiler: &'a Profiler,
-    event_id: StringId,
-    event_kind: StringId,
-    thread_id: u64,
-}
+pub struct TimingGuard<'a>(Option<measureme::TimingGuard<'a, SerializationSink>>);
 
 impl<'a> TimingGuard<'a> {
     #[inline]
@@ -316,14 +312,10 @@ pub fn start(
     ) -> TimingGuard<'a> {
         let thread_id = thread_id_to_u64(std::thread::current().id());
         let raw_profiler = &profiler.profiler;
-        raw_profiler.record_event(event_kind, event_id, thread_id, TimestampKind::Start);
-
-        TimingGuard(Some(TimingGuardInternal {
-            raw_profiler,
-            event_kind,
-            event_id,
-            thread_id,
-        }))
+        let timing_guard = raw_profiler.start_recording_interval_event(event_kind,
+                                                                       event_id,
+                                                                       thread_id);
+        TimingGuard(Some(timing_guard))
     }
 
     #[inline]
@@ -331,15 +323,3 @@ pub fn none() -> TimingGuard<'a> {
         TimingGuard(None)
     }
 }
-
-impl<'a> Drop for TimingGuardInternal<'a> {
-    #[inline]
-    fn drop(&mut self) {
-        self.raw_profiler.record_event(
-            self.event_kind,
-            self.event_id,
-            self.thread_id,
-            TimestampKind::End
-        );
-    }
-}