From 0520698be30eeabd72e66d4b8fa540f727820c33 Mon Sep 17 00:00:00 2001
From: Simonas Kazlauskas <git@kazlauskas.me>
Date: Mon, 8 Aug 2016 01:04:51 +0300
Subject: [PATCH] Count and report time taken by MIR passes

---
 src/librustc/mir/transform.rs                   | 17 +++++++++--------
 src/librustc_mir/transform/dump_mir.rs          |  4 ++--
 src/librustc_mir/transform/simplify_branches.rs |  2 +-
 src/librustc_mir/transform/simplify_cfg.rs      |  2 +-
 4 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/librustc/mir/transform.rs b/src/librustc/mir/transform.rs
index 57601e67504..8cd5f5844d2 100644
--- a/src/librustc/mir/transform.rs
+++ b/src/librustc/mir/transform.rs
@@ -15,7 +15,9 @@ use mir::mir_map::MirMap;
 use mir::repr::{Mir, Promoted};
 use ty::TyCtxt;
 use syntax::ast::NodeId;
+use util::common::time;
 
+use std::borrow::Cow;
 use std::fmt;
 
 /// Where a specific Mir comes from.
@@ -72,12 +74,12 @@ impl<'a, 'tcx> MirSource {
 /// Various information about pass.
 pub trait Pass {
     // fn should_run(Session) to check if pass should run?
-    fn name(&self) -> &str {
+    fn name<'a>(&self) -> Cow<'static, str> {
         let name = unsafe { ::std::intrinsics::type_name::<Self>() };
         if let Some(tail) = name.rfind(":") {
-            &name[tail+1..]
+            Cow::from(&name[tail+1..])
         } else {
-            name
+            Cow::from(name)
         }
     }
     fn disambiguator<'a>(&'a self) -> Option<Box<fmt::Display+'a>> { None }
@@ -162,11 +164,10 @@ impl<'a, 'tcx> Passes {
     }
 
     pub fn run_passes(&mut self, tcx: TyCtxt<'a, 'tcx, 'tcx>, map: &mut MirMap<'tcx>) {
-        for pass in &mut self.plugin_passes {
-            pass.run_pass(tcx, map, &mut self.pass_hooks);
-        }
-        for pass in &mut self.passes {
-            pass.run_pass(tcx, map, &mut self.pass_hooks);
+        let Passes { ref mut passes, ref mut plugin_passes, ref mut pass_hooks } = *self;
+        for pass in plugin_passes.iter_mut().chain(passes.iter_mut()) {
+            time(tcx.sess.time_passes(), &*pass.name(),
+                 || pass.run_pass(tcx, map, pass_hooks));
         }
     }
 
diff --git a/src/librustc_mir/transform/dump_mir.rs b/src/librustc_mir/transform/dump_mir.rs
index 642adeee5cd..694b017bbd7 100644
--- a/src/librustc_mir/transform/dump_mir.rs
+++ b/src/librustc_mir/transform/dump_mir.rs
@@ -26,7 +26,7 @@ impl<'b, 'tcx> MirPass<'tcx> for Marker<'b> {
 }
 
 impl<'b> Pass for Marker<'b> {
-    fn name(&self) -> &str { self.0 }
+    fn name(&self) -> ::std::borrow::Cow<'static, str> { String::from(self.0).into() }
 }
 
 pub struct Disambiguator<'a> {
@@ -58,7 +58,7 @@ impl<'tcx> MirPassHook<'tcx> for DumpMir {
     {
         pretty::dump_mir(
             tcx,
-            pass.name(),
+            &*pass.name(),
             &Disambiguator {
                 pass: pass,
                 is_after: is_after
diff --git a/src/librustc_mir/transform/simplify_branches.rs b/src/librustc_mir/transform/simplify_branches.rs
index b4960c677a1..407e2161610 100644
--- a/src/librustc_mir/transform/simplify_branches.rs
+++ b/src/librustc_mir/transform/simplify_branches.rs
@@ -62,5 +62,5 @@ impl<'l> Pass for SimplifyBranches<'l> {
     }
 
     // avoid calling `type_name` - it contains `<'static>`
-    fn name(&self) -> &str { "SimplifyBranches" }
+    fn name(&self) -> ::std::borrow::Cow<'static, str> { "SimplifyBranches".into() }
 }
diff --git a/src/librustc_mir/transform/simplify_cfg.rs b/src/librustc_mir/transform/simplify_cfg.rs
index c0e7e54050a..8e1b7b44976 100644
--- a/src/librustc_mir/transform/simplify_cfg.rs
+++ b/src/librustc_mir/transform/simplify_cfg.rs
@@ -64,7 +64,7 @@ impl<'l> Pass for SimplifyCfg<'l> {
     }
 
     // avoid calling `type_name` - it contains `<'static>`
-    fn name(&self) -> &str { "SimplifyCfg" }
+    fn name(&self) -> ::std::borrow::Cow<'static, str> { "SimplifyCfg".into() }
 }
 
 pub struct CfgSimplifier<'a, 'tcx: 'a> {