Share locals between members

pkg/compiler/lib/src/js_model/locals.dart

 // Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart2js.js_model.locals;
 
 import 'package:kernel/ast.dart' as ir;
 
-import 'closure.dart' show JClosureClass;
 import '../closure.dart';
 import '../common.dart';
 import '../elements/entities.dart';
 import '../elements/jumps.dart';
 import '../kernel/element_map.dart';
 
 class GlobalLocalsMap {
   Map<MemberEntity, KernelToLocalsMap> _localsMaps =
       <MemberEntity, KernelToLocalsMap>{};
 
+  /// Returns the [KernelToLocalsMap] for [member].
   KernelToLocalsMap getLocalsMap(MemberEntity member) {
     return _localsMaps.putIfAbsent(
         member, () => new KernelToLocalsMapImpl(member));
   }
+
+  /// Associates [localsMap] with [member].
+  ///
+  /// Use this for sharing maps between members that share IR nodes.
+  void setLocalsMap(MemberEntity member, KernelToLocalsMap localsMap) {
+    assert(!_localsMaps.containsKey(member),
+        "Locals map already created for $member.");
+    _localsMaps[member] = localsMap;
+  }
 }
 
 class KernelToLocalsMapImpl implements KernelToLocalsMap {
   final List<MemberEntity> _members = <MemberEntity>[];
   Map<ir.TreeNode, JLocal> _map = <ir.TreeNode, JLocal>{};
   Map<ir.TreeNode, JJumpTarget> _jumpTargetMap;
   Set<ir.BreakStatement> _breaksAsContinue;
 
   MemberEntity get currentMember => _members.last;
 
@@ skipping 85 matching lines @@
     return _jumpTargetMap[node];
   }
 
   @override
   JumpTarget getJumpTargetForWhile(ir.WhileStatement node) {
     _ensureJumpMap(node);
     return _jumpTargetMap[node];
   }
 
   @override
-  Local getLocalVariable(ir.VariableDeclaration node,
-      {bool isClosureCallMethod = false}) {
-    if (isClosureCallMethod && !_map.containsKey(node)) {
-      // Node might correspond to a free variable in the closure class.
-      assert(currentMember.enclosingClass is JClosureClass);
-      return (currentMember.enclosingClass as JClosureClass)
-          .localsMap
-          .getLocalVariable(node);
-    }
+  Local getLocalVariable(ir.VariableDeclaration node) {
     return _map.putIfAbsent(node, () {
       return new JLocal(
           node.name, currentMember, node.parent is ir.FunctionNode);
     });
   }
 
   @override
   // TODO(johnniwinther): Split this out into two methods -- one for
   // FunctionDeclaration and one for FunctionExpression, since basically the
   // whole thing is different depending on the node type. The reason it's not
@@ skipping 216 matching lines @@
       sb.write(memberContext.enclosingClass.name);
       sb.write('.');
     }
     sb.write(memberContext.name);
     sb.write('#');
     sb.write(name);
     sb.write(')');
     return sb.toString();
   }
 }