Correct handling of arrays with callbacks in the prototype chain.

test/mjsunit/setters-on-elements.js

+// Copyright 2011 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: --allow-natives-syntax
+
+// It's nice to run this in Firefox too.
+var standalone = false;
+if (standalone) {
+  assertTrue = function(val) {
+    if (val != true) {
+      print("FAILURE");
+    }
+  }
+
+  assertFalse = function(val) {
+    if (val != false) {
+      print("FAILURE");
+    }
+  }
+
+  optimize = function(name) { }
+} else {
+  optimize = function(name) {
+    %OptimizeFunctionOnNextCall(name);
+  }
+}
+
+var calls = 0;
+
+// Verify that we can't "sneak in" an element setter by modifying the prototype
+// chain.
+(function() {
+  function run(array) {
+    var runlength = 10;
+    calls = 0;
+    for (var i = 0; i < runlength; ++i) {
+      array[0] = 3;
+    }
+    return calls == runlength;
+  }
+
+  var a_prototype = [];
+  a_prototype.__defineSetter__(0, function(val) {
+    calls++;
+  });
+
+  // No callback installed. Drive the setter to monomorphic.
+  var a = [, 3];
+  assertFalse(run(a));
+  run(a);
+  run(a);
+  delete a[0];
+  a.__proto__ = a_prototype;
+  // Altering the prototype chain causes a miss and then we go generic.
+  assertTrue(run(a));
+  assertTrue(run(a));
+
+
+  // Now throw away the IC information by defining a throw-away setter. And try
+  // to crankshaft before we discover we shouldn't be monomorphic.
+  a = [];
+  a.__defineSetter__(0, function() { });
+
+  a = [,3];
+  run(a);
+  run(a);
+  run(a);  // keyed store IC is monomorphic
+  optimize(run);
+  run(a);
+  delete a[0];
+  a.__proto__ = a_prototype;
+  assertTrue(run(a));
+  assertTrue(run(a));
+})();
+
+
+Array.prototype.__defineSetter__(0, function(val) {
+  calls++;
+});
+
+
+(function() {
+  function run(array, index, value) {
+    var runlength = 10;
+    calls = 0;
+    for (var i = 0; i < runlength; ++i) {
+      array[index] = value;
+    }
+    return calls == runlength;
+  }
+
+  // Try "warming up" the ic into a monomorphic state to see if we can trick it
+  // into ignoring the callback. The object map doesn't have the setter callback.

[danno, 2013/10/23 12:22:11]

80 col

+  run({}, 0, true);
+  run({}, 0, true);
+  run({}, 0, true);
+
+  // Make sure the setter is called if the element is not defined,
+  // but is not called if the element is defined.
+  var typeArray = [1,2.5,true];
+  for (var types = 0; types < 3; types++) {
+    value = typeArray[types];
+    for (var i = 0; i < 2; i++) {
+      assertTrue(run([], 0, value));      // undefined
+      assertFalse(run([0], 0, value));    // defined.
+      assertTrue(run([,3], 0, value));   // undefined
+      assertTrue(run(new Array(10), 0, value)); // undefined
+      // "sneak" an element in with shift.
+      o = []; o[1] = 0; o.shift(1);
+      assertFalse(run(o, 0, value));
+      optimize(run);
+      run([], 0, value);
+    }
+  }
+
+  // Make sure we can turn it off.
+  delete Array.prototype[0];
+  assertFalse(run([], 0, true));
+})();
+
+Object.prototype.__defineSetter__(0, function(val) {
+  calls++;
+});
+
+(function() {
+  function run(obj) {
+    var runlength = 10;
+    calls = 0;
+    for (var i = 0; i < runlength; ++i) {
+      obj[0] = true;
+    }
+    return calls == runlength;
+  }
+
+  for (var i = 0; i < 2; i++) {
+    assertTrue(run({}));
+    o = { foo: 3 };
+    assertTrue(run(o));
+    o = {}; o[1] = 3;
+    assertTrue(run(o));
+    o = { 0: 0 };
+    assertFalse(run(o));
+    delete o[0];
+    assertTrue(run(o));
+    optimize(run);
+    run([]);
+  }
+
+  delete Object.prototype[0];
+  assertFalse(run({}));
+})();