// Copyright 2012 the V8 project authors. All rights reserved. // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following // disclaimer in the documentation and/or other materials provided // with the distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived // from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // Flags: --expose-gc // Create a transition tree A (no descriptors) -> B (descriptor for a) -> C // (descriptor for a and c), that all share the descriptor array [a,c]. C is the // owner of the descriptor array. var o = {}; o.a = 1; o.c = 2; // Add a transition B -> D where D has its own descriptor array [a,b] where b is // a constant function. var o1 = {}; o1.a = 1; // Install an enumeration cache in the descriptor array [a,c] at map B. for (var x in o1) { } o1.b = function() { return 1; }; // Return ownership of the descriptor array [a,c] to B and trim it to [a]. o = null; gc(); // Convert the transition B -> D into a transition to B -> E so that E uses the // instance descriptors [a,b] with b being a field. var o2 = {}; o2.a = 1; o2.b = 10; // Create an object with map B and iterate over it. var o3 = {}; o3.a = 1; for (var y in o3) { }