A few cleanups and minor improvements to mir/dataflow

diff --git a/src/librustc_mir/dataflow/graphviz.rs b/src/librustc_mir/dataflow/graphviz.rs
index 97d549987712bbe32a8051f1a005ae0c12f839aa..1d35bb85a21a199243561b508383932342d28e78 100644 (file)
--- a/src/librustc_mir/dataflow/graphviz.rs
+++ b/src/librustc_mir/dataflow/graphviz.rs
@@ -265,15 +265,12 @@ fn nodes(&self) -> dot::Nodes<Node> {
 
     fn edges(&self) -> dot::Edges<Edge> {
         let mir = self.mbcx.mir();
-        // base initial capacity on assumption every block has at
-        // least one outgoing edge (Which should be true for all
-        // blocks but one, the exit-block).
-        let mut edges = Vec::with_capacity(mir.basic_blocks().len());
-        for bb in mir.basic_blocks().indices() {
-            let outgoing = outgoing(mir, bb);
-            edges.extend(outgoing.into_iter());
-        }
-        edges.into_cow()
+
+        mir.basic_blocks()
+           .indices()
+           .flat_map(|bb| outgoing(mir, bb))
+           .collect::<Vec<_>>()
+           .into_cow()
     }
 
     fn source(&self, edge: &Edge) -> Node {

diff --git a/src/librustc_mir/dataflow/impls/borrows.rs b/src/librustc_mir/dataflow/impls/borrows.rs
index 8f3595b17848cbacafe184635e66a6343f6e8491..cb551df910627c4d6e8ed8b044177d0bd9974237 100644 (file)
--- a/src/librustc_mir/dataflow/impls/borrows.rs
+++ b/src/librustc_mir/dataflow/impls/borrows.rs
@@ -168,9 +168,7 @@ fn kill_loans_out_of_scope_at_location(&self,
         // region, then setting that gen-bit will override any
         // potential kill introduced here.
         if let Some(indices) = self.borrows_out_of_scope_at_location.get(&location) {
-            for index in indices {
-                sets.kill(&index);
-            }
+            sets.kill_all(indices);
         }
     }
 

diff --git a/src/librustc_mir/dataflow/mod.rs b/src/librustc_mir/dataflow/mod.rs
index bee7d443c85408b430520fd4abc9612f3468e5cd..d6874e290d4f6cb7398fff416d826d55c70338ab 100644 (file)
--- a/src/librustc_mir/dataflow/mod.rs
+++ b/src/librustc_mir/dataflow/mod.rs
@@ -250,8 +250,7 @@ fn walk_cfg(&mut self, in_out: &mut IdxSet<BD::Idx>) {
     }
 }
 
-fn dataflow_path(context: &str, prepost: &str, path: &str) -> PathBuf {
-    format!("{}_{}", context, prepost);
+fn dataflow_path(context: &str, path: &str) -> PathBuf {
     let mut path = PathBuf::from(path);
     let new_file_name = {
         let orig_file_name = path.file_name().unwrap().to_str().unwrap();
@@ -267,7 +266,7 @@ fn pre_dataflow_instrumentation<P>(&self, p: P) -> io::Result<()>
         where P: Fn(&BD, BD::Idx) -> DebugFormatted
     {
         if let Some(ref path_str) = self.print_preflow_to {
-            let path = dataflow_path(BD::name(), "preflow", path_str);
+            let path = dataflow_path(BD::name(), path_str);
             graphviz::print_borrowck_graph_to(self, &path, p)
         } else {
             Ok(())
@@ -278,9 +277,9 @@ fn post_dataflow_instrumentation<P>(&self, p: P) -> io::Result<()>
         where P: Fn(&BD, BD::Idx) -> DebugFormatted
     {
         if let Some(ref path_str) = self.print_postflow_to {
-            let path = dataflow_path(BD::name(), "postflow", path_str);
+            let path = dataflow_path(BD::name(), path_str);
             graphviz::print_borrowck_graph_to(self, &path, p)
-        } else{
+        } else {
             Ok(())
         }
     }

diff --git a/src/librustc_mir/dataflow/move_paths/builder.rs b/src/librustc_mir/dataflow/move_paths/builder.rs
index 2148363c79712ee7ab17c0ae86c5cfaaef903491..732aa7904d3198ebd8d551896d8dffd898161065 100644 (file)
--- a/src/librustc_mir/dataflow/move_paths/builder.rs
+++ b/src/librustc_mir/dataflow/move_paths/builder.rs
@@ -201,7 +201,7 @@ fn finalize(
             "done dumping moves"
         });
 
-        if self.errors.len() > 0 {
+        if !self.errors.is_empty() {
             Err((self.data, self.errors))
         } else {
             Ok(self.data)