dart2js cps: Direct access on JS arrays.

pkg/compiler/lib/src/js_backend/codegen/codegen.dart

 // Copyright (c) 2014, 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 code_generator;
 
 import 'glue.dart';
 
 import '../../tree_ir/tree_ir_nodes.dart' as tree_ir;
 import '../../tree_ir/tree_ir_nodes.dart' show BuiltinOperator;
@@ skipping 646 matching lines @@
 
   @override
   js.Expression visitSetStatic(tree_ir.SetStatic node) {
     assert(node.element is FieldElement);
     registry.registerStaticUse(node.element.declaration);
     js.Expression field = glue.staticFieldAccess(node.element);
     js.Expression value = visitExpression(node.value);
     return new js.Assignment(field, value);
   }
 
+  @override
+  js.Expression visitGetLength(tree_ir.GetLength node) {
+    return new js.PropertyAccess.field(visitExpression(node.object), 'length');
+  }
+
+  @override
+  js.Expression visitGetIndex(tree_ir.GetIndex node) {
+    return new js.PropertyAccess(
+        visitExpression(node.object),
+        visitExpression(node.index));
+  }
+
+  @override
+  js.Expression visitSetIndex(tree_ir.SetIndex node) {
+    return js.js('#[#] = #',
+        [visitExpression(node.object),
+         visitExpression(node.index),
+         visitExpression(node.value)]);
+  }
+
   js.Expression buildStaticHelperInvocation(FunctionElement helper,
                                             List<js.Expression> arguments) {
     registry.registerStaticUse(helper);
     return buildStaticInvoke(helper, arguments);
   }
 
   @override
   js.Expression visitReifyRuntimeType(tree_ir.ReifyRuntimeType node) {
     FunctionElement createType = glue.getCreateRuntimeType();
     FunctionElement typeToString = glue.getRuntimeTypeToString();
@@ skipping 89 matching lines @@
         return js.js("typeof # === 'number' && Math.floor(#) === #", args);
     }
   }
 
   visitFunctionExpression(tree_ir.FunctionExpression node) {
     // FunctionExpressions are currently unused.
     // We might need them if we want to emit raw JS nested functions.
     throw 'FunctionExpressions should not be used';
   }
 }