From 7acaa73377e9ed8b337a66c968286e6581dc7b24 Mon Sep 17 00:00:00 2001
From: Patrick Walton <pcwalton@mimiga.net>
Date: Sat, 21 Dec 2013 15:51:39 -0800
Subject: [PATCH] librustc: De-`@mut` `ScopeInfo::cleanup_paths`

---
 src/librustc/middle/trans/base.rs   | 15 +++++++++++----
 src/librustc/middle/trans/common.rs | 13 ++++++++++---
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/src/librustc/middle/trans/base.rs b/src/librustc/middle/trans/base.rs
index ecd6258bf0f..f576d1cc97a 100644
--- a/src/librustc/middle/trans/base.rs
+++ b/src/librustc/middle/trans/base.rs
@@ -1223,7 +1223,7 @@ pub fn simple_block_scope(parent: Option<@mut ScopeInfo>,
         loop_break: None,
         loop_label: None,
         cleanups: RefCell::new(~[]),
-        cleanup_paths: ~[],
+        cleanup_paths: RefCell::new(~[]),
         landing_pad: None,
         node_info: node_info,
     }
@@ -1253,7 +1253,7 @@ pub fn loop_scope_block(bcx: @Block,
         loop_break: Some(loop_break),
         loop_label: loop_label,
         cleanups: RefCell::new(~[]),
-        cleanup_paths: ~[],
+        cleanup_paths: RefCell::new(~[]),
         landing_pad: None,
         node_info: opt_node_info,
     }), bcx.is_lpad, n, opt_node_info);
@@ -1333,7 +1333,12 @@ pub fn cleanup_and_leave(bcx: @Block,
                         let mut skip = 0;
                         let mut dest = None;
                         {
-                            let r = (*inf).cleanup_paths.rev_iter().find(|cp| cp.target == leave);
+                            let cleanup_paths = inf.cleanup_paths.borrow();
+                            let r = cleanup_paths.get()
+                                                 .rev_iter()
+                                                 .find(|cp| {
+                                cp.target == leave
+                            });
                             for cp in r.iter() {
                                 let cleanups = inf.cleanups.borrow();
                                 if cp.size == cleanups.get().len() {
@@ -1348,7 +1353,9 @@ pub fn cleanup_and_leave(bcx: @Block,
                         let sub_cx = sub_block(bcx, "cleanup");
                         Br(bcx, sub_cx.llbb);
                         let cleanups = inf.cleanups.borrow();
-                        inf.cleanup_paths.push(cleanup_path {
+                        let mut cleanup_paths = inf.cleanup_paths
+                                                   .borrow_mut();
+                        cleanup_paths.get().push(cleanup_path {
                             target: leave,
                             size: cleanups.get().len(),
                             dest: sub_cx.llbb
diff --git a/src/librustc/middle/trans/common.rs b/src/librustc/middle/trans/common.rs
index 9e25756fc49..9940bdac8d8 100644
--- a/src/librustc/middle/trans/common.rs
+++ b/src/librustc/middle/trans/common.rs
@@ -432,8 +432,15 @@ pub struct cleanup_path {
 
 pub fn shrink_scope_clean(scope_info: &mut ScopeInfo, size: uint) {
     scope_info.landing_pad = None;
-    scope_info.cleanup_paths = scope_info.cleanup_paths.iter()
-            .take_while(|&cu| cu.size <= size).map(|&x|x).collect();
+    let new_cleanup_paths = {
+        let cleanup_paths = scope_info.cleanup_paths.borrow();
+        cleanup_paths.get()
+                     .iter()
+                     .take_while(|&cu| cu.size <= size)
+                     .map(|&x| x)
+                     .collect()
+    };
+    scope_info.cleanup_paths.set(new_cleanup_paths)
 }
 
 pub fn grow_scope_clean(scope_info: &mut ScopeInfo) {
@@ -625,7 +632,7 @@ pub struct ScopeInfo {
     cleanups: RefCell<~[cleanup]>,
     // Existing cleanup paths that may be reused, indexed by destination and
     // cleared when the set of cleanups changes.
-    cleanup_paths: ~[cleanup_path],
+    cleanup_paths: RefCell<~[cleanup_path]>,
     // Unwinding landing pad. Also cleared when cleanups change.
     landing_pad: Option<BasicBlockRef>,
     // info about the AST node this scope originated from, if any