deps: upgrade v8 to 3.31.74.1

PR-URL: https://github.com/iojs/io.js/pull/243
Reviewed-By: Fedor Indutny <fedor@indutny.com>
Reviewed-By: Trevor Norris <trev.norris@gmail.com>

12 files changed, 527 insertions, 61 deletions

diff --git a/deps/v8/test/mjsunit/es6/collections.js b/deps/v8/test/mjsunit/es6/collections.js
index 60ce46b2e5..92cd087839 100644
--- a/deps/v8/test/mjsunit/es6/collections.js
+++ b/deps/v8/test/mjsunit/es6/collections.js
@@ -266,7 +266,6 @@ assertTrue(WeakMap.prototype.set instanceof Function)
 assertTrue(WeakMap.prototype.get instanceof Function)
 assertTrue(WeakMap.prototype.has instanceof Function)
 assertTrue(WeakMap.prototype.delete instanceof Function)
-assertTrue(WeakMap.prototype.clear instanceof Function)
 
 
 // Test some common JavaScript idioms for WeakSets
@@ -275,7 +274,6 @@ assertTrue(s instanceof WeakSet);
 assertTrue(WeakSet.prototype.add instanceof Function)
 assertTrue(WeakSet.prototype.has instanceof Function)
 assertTrue(WeakSet.prototype.delete instanceof Function)
-assertTrue(WeakSet.prototype.clear instanceof Function)
 
 
 // Test class of instance and prototype.
@@ -471,30 +469,6 @@ for (var i = 9; i >= 0; i--) {
 })();
 
 
-// Test WeakMap clear
-(function() {
-  var k = new Object();
-  var w = new WeakMap();
-  w.set(k, 23);
-  assertTrue(w.has(k));
-  assertEquals(23, w.get(k));
-  w.clear();
-  assertFalse(w.has(k));
-  assertEquals(undefined, w.get(k));
-})();
-
-
-// Test WeakSet clear
-(function() {
-  var k = new Object();
-  var w = new WeakSet();
-  w.add(k);
-  assertTrue(w.has(k));
-  w.clear();
-  assertFalse(w.has(k));
-})();
-
-
 (function TestMinusZeroSet() {
   var s = new Set();
   s.add(-0);
diff --git a/deps/v8/test/mjsunit/es6/debug-stepin-microtasks.js b/deps/v8/test/mjsunit/es6/debug-stepin-microtasks.js
new file mode 100644
index 0000000000..8dbdb3457a
--- /dev/null
+++ b/deps/v8/test/mjsunit/es6/debug-stepin-microtasks.js
@@ -0,0 +1,101 @@
+// Copyright 2014 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax --expose-debug-as debug
+
+Debug = debug.Debug
+var exception = null;
+var break_count = 0;
+var expected_breaks = -1;
+
+function listener(event, exec_state, event_data, data) {
+  try {
+    if (event == Debug.DebugEvent.Break) {
+      assertTrue(exec_state.frameCount() != 0, "FAIL: Empty stack trace");
+      if (!break_count) {
+        // Count number of expected breakpoints in this source file.
+        var source_text = exec_state.frame(0).func().script().source();
+        expected_breaks = source_text.match(/\/\/\s*Break\s+\d+\./g).length;
+        print("Expected breaks: " + expected_breaks);
+      }
+      var source = exec_state.frame(0).sourceLineText();
+      print("paused at: " + source);
+      assertTrue(source.indexOf("// Break " + break_count + ".") > 0,
+                 "Unexpected pause at: " + source + "\n" +
+                 "Expected: // Break " + break_count + ".");
+      if (source.indexOf("StepOver.") !== -1) {
+        exec_state.prepareStep(Debug.StepAction.StepNext, 1);
+      } else {
+        exec_state.prepareStep(Debug.StepAction.StepIn, 1);
+      }
+      ++break_count;
+    }
+  } catch (e) {
+    exception = e;
+    print(e, e.stack);
+  }
+};
+
+Debug.setListener(listener);
+
+Promise.resolve(42)
+  .then(promise1)
+  .then(Object) // Should skip stepping into native.
+  .then(Boolean) // Should skip stepping into native.
+  .then(promise2)
+  .catch(promise3)
+  .catch(function(e) {
+    %AbortJS("FAIL: uncaught exception " + e);
+  });
+
+function promise1() {
+  debugger; // Break 0.
+  return exception || 1; // Break 1.
+} // Break 2.
+
+function promise2() {
+  throw new Error; // Break 3.
+}
+
+function promise3() {
+  installObservers(); // Break 4. StepOver.
+  return break_count; // Break 5.
+} // Break 6.
+
+function installObservers() {
+  var dummy = {};
+  Object.observe(dummy, observer1);
+  Object.observe(dummy, Object); // Should skip stepping into native.
+  Object.observe(dummy, Boolean); // Should skip stepping into native.
+  Object.observe(dummy, observer2);
+  dummy.foo = 1;
+}
+
+function observer1() {
+  return exception || 3; // Break 7.
+} // Break 8.
+
+function observer2() {
+  Promise.resolve().then(promise4); // Break 9. StepOver.
+  return break_count + 1; // Break 10.
+} // Break 11.
+
+function promise4() {
+  finalize(); // Break 12. StepOver.
+  return 0; // Break 13.
+} // Break 14. StepOver.
+
+function finalize() {
+  var dummy = {};
+  Object.observe(dummy, function() {
+    if (expected_breaks !== break_count) {
+      %AbortJS("FAIL: expected <" + expected_breaks + "> breaks instead of <" +
+               break_count + ">");
+    }
+    if (exception !== null) {
+      %AbortJS("FAIL: exception: " + exception);
+    }
+  });
+  dummy.foo = 1;
+}
diff --git a/deps/v8/test/mjsunit/es6/debug-stepnext-for.js b/deps/v8/test/mjsunit/es6/debug-stepnext-for.js
new file mode 100644
index 0000000000..98af911ae3
--- /dev/null
+++ b/deps/v8/test/mjsunit/es6/debug-stepnext-for.js
@@ -0,0 +1,116 @@
+// Copyright 2014 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --expose-debug-as debug --harmony
+
+Debug = debug.Debug;
+var break_count = 0
+var exception = null;
+var log = []
+
+var s = 0;
+var a = [1, 2, 3];
+var i = 0;
+
+function f() {
+  "use strict";
+  debugger;                      // Break a
+  var j;                         // Break b
+
+  for (var i in null) {          // Break c
+    s += a[i];
+  }
+
+  for (j in null) {              // Break d
+    s += a[j];
+  }
+
+  for (var i in a) {             // Break e
+    s += a[i];                   // Break E
+  }
+
+  for (j in a) {                 // Break f
+    s += a[j];                   // Break F
+  }
+
+  for (let i in a) {             // Break g
+    s += a[i];                   // Break G
+  }
+
+  for (var i of a) {             // Break h
+    s += i;                      // Break H
+  }
+
+  for (j of a) {                 // Break i
+    s += j;                      // Break I
+  }
+
+  for (let i of a) {             // Break j
+    s += i;                      // Break J
+  }
+
+  for (var i = 0; i < 3; i++) {  // Break k
+    s += a[i];                   // Break K
+  }
+
+  for (j = 0; j < 3; j++) {      // Break l
+    s += a[j];                   // Break L
+  }
+
+  // TODO(yangguo): add test case for for-let.
+}                                // Break y
+
+function listener(event, exec_state, event_data, data) {
+  if (event != Debug.DebugEvent.Break) return;
+  try {
+    var line = exec_state.frame(0).sourceLineText();
+    var col = exec_state.frame(0).sourceColumn();
+    print(line);
+    var match = line.match(/\/\/ Break (\w)$/);
+    assertEquals(2, match.length);
+    log.push(match[1] + col);
+    exec_state.prepareStep(Debug.StepAction.StepNext, 1);
+    break_count++;
+  } catch (e) {
+    exception = e;
+  }
+}
+
+Debug.setListener(listener);
+f();
+Debug.setListener(null);         // Break z
+
+print(JSON.stringify(log));
+// The let declaration differs from var in that the loop variable
+// is declared in every iteration.
+var expected = [
+  // Entry
+  "a2","b2",
+  // Empty for-in-var: var decl, get enumerable
+  "c7","c16",
+  // Empty for-in: get enumerable
+  "d12",
+  // For-in-var: var decl, get enumerable, assign, body, assign, body, ...
+  "e7","e16","e11","E4","e11","E4","e11","E4","e11",
+  // For-in: get enumerable, assign, body, assign, body, ...
+  "f12","f7","F4","f7","F4","f7","F4","f7",
+  // For-in-let: get enumerable, next, new let, body, next, new let, ...
+  "g16","g11","g7","G4","g11","g7","G4","g11","g7","G4","g11",
+  // For-of-var: var decl, next(), body, next(), body, ...
+  "h7","h16","H4","h16","H4","h16","H4","h16",
+  // For-of: next(), body, next(), body, ...
+  "i12","I4","i12","I4","i12","I4","i12",
+  // For-of-let: next(), new let, body, next(), new let, ...
+  "j16","j7","J4","j16","j7","J4","j16","j7","J4","j16",
+  // For-var: var decl, condition, body, next, condition, body, ...
+  "k7","k20","K4","k23","k20","K4","k23","k20","K4","k23","k20",
+  // For: init, condition, body, next, condition, body, ...
+  "l11","l16","L4","l19","l16","L4","l19","l16","L4","l19","l16",
+  // Exit.
+  "y0","z0",
+]
+
+assertArrayEquals(expected, log);
+assertEquals(48, s);
+assertNull(exception);
diff --git a/deps/v8/test/mjsunit/es6/generators-debug-scopes.js b/deps/v8/test/mjsunit/es6/generators-debug-scopes.js
index d55e5612de..126572d16f 100644
--- a/deps/v8/test/mjsunit/es6/generators-debug-scopes.js
+++ b/deps/v8/test/mjsunit/es6/generators-debug-scopes.js
@@ -97,6 +97,7 @@ function CheckScopeChain(scopes, exec_state) {
     assertEquals(i, response.body.scopes[i].index);
     assertEquals(scopes[i], response.body.scopes[i].type);
     if (scopes[i] == debug.ScopeType.Local ||
+        scopes[i] == debug.ScopeType.Script ||
         scopes[i] == debug.ScopeType.Closure) {
       assertTrue(response.body.scopes[i].object.ref < 0);
     } else {
@@ -159,6 +160,7 @@ function CheckScopeContent(content, number, exec_state) {
   assertEquals(scope.scopeType(), response.body.type);
   assertEquals(number, response.body.index);
   if (scope.scopeType() == debug.ScopeType.Local ||
+      scope.scopeType() == debug.ScopeType.Script ||
       scope.scopeType() == debug.ScopeType.Closure) {
     assertTrue(response.body.object.ref < 0);
   } else {
@@ -178,6 +180,7 @@ RunTest("Local 1",
         [],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({}, 0, exec_state);
         });
@@ -188,6 +191,7 @@ RunTest("Local 2",
         [1],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1}, 0, exec_state);
         });
@@ -198,6 +202,7 @@ RunTest("Local 3",
         [1],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1,x:3}, 0, exec_state);
         });
@@ -208,6 +213,7 @@ RunTest("Local 4",
         [1, 2],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1,b:2,x:3,y:4}, 0, exec_state);
         });
@@ -218,6 +224,7 @@ RunTest("Local 5",
         [],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({}, 0, exec_state);
         });
@@ -228,6 +235,7 @@ RunTest("Local 6",
         [],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({i:5}, 0, exec_state);
         });
@@ -242,6 +250,7 @@ RunTest("Local 7",
         [1, 2],
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1,b:2,x:3,y:4,i:5,j:6}, 0, exec_state);
         });
@@ -254,6 +263,7 @@ RunTest("With",
           CheckScopeChain([debug.ScopeType.With,
                            debug.ScopeType.With,
                            debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({}, 0, exec_state);
           CheckScopeContent({}, 1, exec_state);
@@ -267,6 +277,7 @@ RunTest("Closure 1",
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Local,
                            debug.ScopeType.Closure,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({a:1}, 1, exec_state);
         },
@@ -305,6 +316,7 @@ RunTest("The full monty",
                            debug.ScopeType.With,
                            debug.ScopeType.Closure,
                            debug.ScopeType.Closure,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({b:16}, 0, exec_state);
           CheckScopeContent({a:15}, 1, exec_state);
@@ -321,6 +333,7 @@ RunTest("Catch block 1",
         function (exec_state) {
           CheckScopeChain([debug.ScopeType.Catch,
                            debug.ScopeType.Local,
+                           debug.ScopeType.Script,
                            debug.ScopeType.Global], exec_state);
           CheckScopeContent({e:'Exception'}, 0, exec_state);
         });
diff --git a/deps/v8/test/mjsunit/es6/generators-iteration.js b/deps/v8/test/mjsunit/es6/generators-iteration.js
index b6fcdaa487..faeb68380f 100644
--- a/deps/v8/test/mjsunit/es6/generators-iteration.js
+++ b/deps/v8/test/mjsunit/es6/generators-iteration.js
@@ -41,10 +41,7 @@ function assertIteratorIsClosed(iter) {
 }
 
 function assertThrownIteratorIsClosed(iter) {
-  // TODO(yusukesuzuki): Since status of a thrown generator is "executing",
-  // following tests are failed.
-  // https://code.google.com/p/v8/issues/detail?id=3096
-  // assertIteratorIsClosed(iter);
+  assertIteratorIsClosed(iter);
 }
 
 function TestGeneratorResultPrototype() {
diff --git a/deps/v8/test/mjsunit/es6/generators-mirror.js b/deps/v8/test/mjsunit/es6/generators-mirror.js
index 6925285882..bf21f4dff5 100644
--- a/deps/v8/test/mjsunit/es6/generators-mirror.js
+++ b/deps/v8/test/mjsunit/es6/generators-mirror.js
@@ -24,7 +24,7 @@ MirrorRefCache.prototype.lookup = function(handle) {
   return this.refs_[handle];
 }
 
-function TestGeneratorMirror(g, test) {
+function TestGeneratorMirror(g, status, line, column, receiver) {
   // Create mirror and JSON representation.
   var mirror = debug.MakeMirror(g);
   var serializer = debug.MakeMirrorSerializer();
@@ -44,41 +44,69 @@ function TestGeneratorMirror(g, test) {
   assertFalse(mirror.isPrimitive());
   assertEquals('Generator', mirror.className());
 
-  assertTrue(mirror.receiver().isUndefined());
+  assertEquals(receiver, mirror.receiver().value());
   assertEquals(generator, mirror.func().value());
 
-  test(mirror);
-}
+  assertEquals(status, mirror.status());
+
+  // Note that line numbers are 0-based, not 1-based.
+  var loc = mirror.sourceLocation();
+  if (status === 'suspended') {
+    assertTrue(!!loc);
+    assertEquals(line, loc.line);
+    assertEquals(column, loc.column);
+  } else {
+    assertEquals(undefined, loc);
+  }
 
-var iter = generator(function () {
-  assertEquals('running', debug.MakeMirror(iter).status());
-})
+  TestInternalProperties(mirror, status, receiver);
+}
 
-// Note that line numbers are 0-based, not 1-based.
-function assertSourceLocation(loc, line, column) {
-  assertEquals(line, loc.line);
-  assertEquals(column, loc.column);
+function TestInternalProperties(mirror, status, receiver) {
+  var properties = mirror.internalProperties();
+  assertEquals(3, properties.length);
+  assertEquals("[[GeneratorStatus]]", properties[0].name());
+  assertEquals(status, properties[0].value().value());
+  assertEquals("[[GeneratorFunction]]", properties[1].name());
+  assertEquals(generator, properties[1].value().value());
+  assertEquals("[[GeneratorReceiver]]", properties[2].name());
+  assertEquals(receiver, properties[2].value().value());
 }
 
-TestGeneratorMirror(iter, function (mirror) {
-  assertEquals('suspended', mirror.status())
-  assertSourceLocation(mirror.sourceLocation(), 7, 19);
+var iter = generator(function() {
+  var mirror = debug.MakeMirror(iter);
+  assertEquals('running', mirror.status());
+  assertEquals(undefined, mirror.sourceLocation());
+  TestInternalProperties(mirror, 'running');
 });
 
+TestGeneratorMirror(iter, 'suspended', 7, 19);
+
 iter.next();
-TestGeneratorMirror(iter, function (mirror) {
-  assertEquals('suspended', mirror.status())
-  assertSourceLocation(mirror.sourceLocation(), 9, 2);
-});
+TestGeneratorMirror(iter, 'suspended', 9, 2);
 
 iter.next();
-TestGeneratorMirror(iter, function (mirror) {
-  assertEquals('suspended', mirror.status())
-  assertSourceLocation(mirror.sourceLocation(), 11, 2);
-});
+TestGeneratorMirror(iter, 'suspended', 11, 2);
 
 iter.next();
-TestGeneratorMirror(iter, function (mirror) {
-  assertEquals('closed', mirror.status())
+TestGeneratorMirror(iter, 'closed');
+
+// Test generator with receiver.
+var obj = {foo: 42};
+var iter2 = generator.call(obj, function() {
+  var mirror = debug.MakeMirror(iter2);
+  assertEquals('running', mirror.status());
   assertEquals(undefined, mirror.sourceLocation());
+  TestInternalProperties(mirror, 'running', obj);
 });
+
+TestGeneratorMirror(iter2, 'suspended', 7, 19, obj);
+
+iter2.next();
+TestGeneratorMirror(iter2, 'suspended', 9, 2, obj);
+
+iter2.next();
+TestGeneratorMirror(iter2, 'suspended', 11, 2, obj);
+
+iter2.next();
+TestGeneratorMirror(iter2, 'closed', 0, 0, obj);
diff --git a/deps/v8/test/mjsunit/es6/generators-objects.js b/deps/v8/test/mjsunit/es6/generators-objects.js
index 25bd0de79d..8039ca8bb1 100644
--- a/deps/v8/test/mjsunit/es6/generators-objects.js
+++ b/deps/v8/test/mjsunit/es6/generators-objects.js
@@ -67,6 +67,8 @@ function TestGeneratorObject() {
   assertEquals("Generator", %_ClassOf(iter));
   assertEquals("[object Generator]", String(iter));
   assertEquals("[object Generator]", Object.prototype.toString.call(iter));
+  var gf = iter.__proto__.constructor;
+  assertEquals("[object GeneratorFunction]", Object.prototype.toString.call(gf));
   assertEquals([], Object.getOwnPropertyNames(iter));
   assertTrue(iter !== new g());
 }
diff --git a/deps/v8/test/mjsunit/es6/generators-states.js b/deps/v8/test/mjsunit/es6/generators-states.js
new file mode 100644
index 0000000000..0a2173a919
--- /dev/null
+++ b/deps/v8/test/mjsunit/es6/generators-states.js
@@ -0,0 +1,67 @@
+// Copyright 2014 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Test generator states.
+
+function Foo() {}
+function Bar() {}
+
+function assertIteratorResult(value, done, result) {
+  assertEquals({ value: value, done: done}, result);
+}
+
+function assertIteratorIsClosed(iter) {
+  assertIteratorResult(undefined, true, iter.next());
+  // Next and throw on a closed iterator.
+  assertDoesNotThrow(function() { iter.next(); });
+  assertThrows(function() { iter.throw(new Bar); }, Bar);
+}
+
+var iter;
+function* nextGenerator() { yield iter.next(); }
+function* throwGenerator() { yield iter.throw(new Bar); }
+
+// Throw on a suspendedStart iterator.
+iter = nextGenerator();
+assertThrows(function() { iter.throw(new Foo) }, Foo)
+assertThrows(function() { iter.throw(new Foo) }, Foo)
+assertIteratorIsClosed(iter);
+
+// The same.
+iter = throwGenerator();
+assertThrows(function() { iter.throw(new Foo) }, Foo)
+assertThrows(function() { iter.throw(new Foo) }, Foo)
+assertIteratorIsClosed(iter);
+
+// Next on an executing iterator raises a TypeError.
+iter = nextGenerator();
+assertThrows(function() { iter.next() }, TypeError)
+assertIteratorIsClosed(iter);
+
+// Throw on an executing iterator raises a TypeError.
+iter = throwGenerator();
+assertThrows(function() { iter.next() }, TypeError)
+assertIteratorIsClosed(iter);
+
+// Next on an executing iterator doesn't change the state of the
+// generator.
+iter = (function* () {
+  try {
+    iter.next();
+    yield 1;
+  } catch (e) {
+    try {
+      // This next() should raise the same exception, because the first
+      // next() left the iter in the executing state.
+      iter.next();
+      yield 2;
+    } catch (e) {
+      yield 3;
+    }
+  }
+  yield 4;
+})();
+assertIteratorResult(3, false, iter.next());
+assertIteratorResult(4, false, iter.next());
+assertIteratorIsClosed(iter);
diff --git a/deps/v8/test/mjsunit/es6/math-log2-log10.js b/deps/v8/test/mjsunit/es6/math-log2-log10.js
index 4479894d7d..fa3f46807a 100644
--- a/deps/v8/test/mjsunit/es6/math-log2-log10.js
+++ b/deps/v8/test/mjsunit/es6/math-log2-log10.js
@@ -25,6 +25,8 @@
 // (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
+
 [Math.log10, Math.log2].forEach( function(fun) {
   assertTrue(isNaN(fun(NaN)));
   assertTrue(isNaN(fun(fun)));
@@ -39,7 +41,59 @@
   assertEquals("Infinity", String(fun(Infinity)));
 });
 
-for (var i = -300; i < 300; i += 0.7) {
-  assertEqualsDelta(i, Math.log10(Math.pow(10, i)), 1E-13);
-  assertEqualsDelta(i, Math.log2(Math.pow(2, i)), 1E-13);
+for (var i = -310; i <= 308; i += 0.5) {
+  assertEquals(i, Math.log10(Math.pow(10, i)));
+  // Square roots are tested below.
+  if (i != -0.5 && i != 0.5) assertEquals(i, Math.log2(Math.pow(2, i)));
+}
+
+// Test denormals.
+assertEquals(-307.77759430519706, Math.log10(1.5 * Math.pow(2, -1023)));
+
+// Test Math.log2(2^k) for -1074 <= k <= 1023.
+var n = -1074;
+// This loop covers n from -1074 to -1043
+for (var lowbits = 1; lowbits <= 0x80000000; lowbits *= 2) {
+  var x = %_ConstructDouble(0, lowbits);
+  assertEquals(n, Math.log2(x));
+  n++;
+}
+// This loop covers n from -1042 to -1023
+for (var hibits = 1; hibits <= 0x80000; hibits *= 2) {
+  var x = %_ConstructDouble(hibits, 0);
+  assertEquals(n, Math.log2(x));
+  n++;
+}
+// The rest of the normal values of 2^n
+var x = 1;
+for (var n = -1022; n <= 1023; ++n) {
+  var x = Math.pow(2, n);
+  assertEquals(n, Math.log2(x));
+}
+
+// Test special values.
+// Expectation isn't exactly 1/2 because Math.SQRT2 isn't exactly sqrt(2).
+assertEquals(0.5000000000000001, Math.log2(Math.SQRT2));
+
+// Expectation isn't exactly -1/2 because Math.SQRT1_2 isn't exactly sqrt(1/2).
+assertEquals(-0.4999999999999999, Math.log2(Math.SQRT1_2));
+
+assertEquals(3.321928094887362, Math.log2(10));
+assertEquals(6.643856189774724, Math.log2(100));
+
+// Test relationships
+x = 1;
+for (var k = 0; k < 1000; ++k) {
+  var y = Math.abs(Math.log2(x) + Math.log2(1/x));
+  assertEqualsDelta(0, y, 1.5e-14);
+  x *= 1.1;
+}
+
+x = Math.pow(2, -100);
+for (var k = 0; k < 1000; ++k) {
+  var y = Math.log2(x);
+  var expected = Math.log(x) / Math.LN2;
+  var err = Math.abs(y - expected) / expected;
+  assertEqualsDelta(0, err, 1e-15);
+  x *= 1.1;
 }
diff --git a/deps/v8/test/mjsunit/es6/mirror-collections.js b/deps/v8/test/mjsunit/es6/mirror-collections.js
index e10f5c1a98..81a98b8a58 100644
--- a/deps/v8/test/mjsunit/es6/mirror-collections.js
+++ b/deps/v8/test/mjsunit/es6/mirror-collections.js
@@ -51,6 +51,7 @@ map.set(o2, 22);
 map.delete(o1);
 var mapMirror = debug.MakeMirror(map);
 testMapMirror(mapMirror);
+
 var entries = mapMirror.entries();
 assertEquals(1, entries.length);
 assertSame(o2, entries[0].key);
@@ -59,6 +60,7 @@ map.set(o1, 33);
 map.set(o3, o2);
 map.delete(o2);
 map.set(undefined, 44);
+
 entries = mapMirror.entries();
 assertEquals(3, entries.length);
 assertSame(o1, entries[0].key);
@@ -68,6 +70,10 @@ assertSame(o2, entries[1].value);
 assertEquals(undefined, entries[2].key);
 assertEquals(44, entries[2].value);
 
+assertEquals(3, mapMirror.entries(0).length);
+assertEquals(1, mapMirror.entries(1).length);
+assertEquals(2, mapMirror.entries(2).length);
+
 // Test the mirror object for Sets
 var set = new Set();
 set.add(o1);
@@ -78,6 +84,7 @@ var setMirror = debug.MakeMirror(set);
 testSetMirror(setMirror);
 var values = setMirror.values();
 assertEquals(2, values.length);
+assertEquals(1, setMirror.values(1).length);
 assertSame(o2, values[0]);
 assertEquals(undefined, values[1]);
 
@@ -96,6 +103,8 @@ gc();
 function testWeakMapEntries(weakMapMirror) {
   var entries = weakMapMirror.entries();
   assertEquals(2, entries.length);
+  assertEquals(2, weakMapMirror.entries(0).length);
+  assertEquals(1, weakMapMirror.entries(1).length);
   var found = 0;
   for (var i = 0; i < entries.length; i++) {
     if (Object.is(entries[i].key, o1)) {
@@ -129,6 +138,8 @@ gc();
 function testWeakSetValues(weakSetMirror) {
   var values = weakSetMirror.values();
   assertEquals(2, values.length);
+  assertEquals(2, weakSetMirror.values(0).length);
+  assertEquals(1, weakSetMirror.values(1).length);
   var found = 0;
   for (var i = 0; i < values.length; i++) {
     if (Object.is(values[i], o1)) {
diff --git a/deps/v8/test/mjsunit/es6/mirror-iterators.js b/deps/v8/test/mjsunit/es6/mirror-iterators.js
index 02fe7ffde0..22ce42493f 100644
--- a/deps/v8/test/mjsunit/es6/mirror-iterators.js
+++ b/deps/v8/test/mjsunit/es6/mirror-iterators.js
@@ -5,21 +5,40 @@
 // Flags: --expose-debug-as debug
 // Test the mirror object for collection iterators.
 
-function testIteratorMirror(iter, offset, expected) {
+function testIteratorMirror(iter, offset, expected, opt_limit) {
   while (offset-- > 0) iter.next();
 
   var mirror = debug.MakeMirror(iter);
   assertTrue(mirror.isIterator());
 
-  var preview = mirror.preview();
+  var preview = mirror.preview(opt_limit);
   assertArrayEquals(expected, preview);
 
   // Check that iterator has not changed after taking preview.
   var values = [];
-  for (var i of iter) values.push(i);
+  for (var i of iter) {
+    if (opt_limit && values.length >= opt_limit) break;
+    values.push(i);
+  }
   assertArrayEquals(expected, values);
 }
 
+function testIteratorInternalProperties(iter, offset, kind, index, has_more) {
+  while (offset-- > 0) iter.next();
+
+  var mirror = debug.MakeMirror(iter);
+  assertTrue(mirror.isIterator());
+
+  var properties = mirror.internalProperties();
+  assertEquals(3, properties.length);
+  assertEquals("[[IteratorHasMore]]", properties[0].name());
+  assertEquals(has_more, properties[0].value().value());
+  assertEquals("[[IteratorIndex]]", properties[1].name());
+  assertEquals(index, properties[1].value().value());
+  assertEquals("[[IteratorKind]]", properties[2].name());
+  assertEquals(kind, properties[2].value().value());
+}
+
 var o1 = { foo: 1 };
 var o2 = { foo: 2 };
 
@@ -39,6 +58,16 @@ testIteratorMirror(map.keys(), 2, []);
 testIteratorMirror(map.values(), 2, []);
 testIteratorMirror(map.entries(), 2, []);
 
+// Test with maximum limit.
+testIteratorMirror(map.keys(), 0, [41], 1);
+testIteratorMirror(map.values(), 0, [42], 1);
+testIteratorMirror(map.entries(), 0, [[41, 42]], 1);
+
+testIteratorInternalProperties(map.keys(), 0, "keys", 0, true);
+testIteratorInternalProperties(map.values(), 1, "values", 1, true);
+testIteratorInternalProperties(map.entries(), 2, "entries", 2, false);
+testIteratorInternalProperties(map.keys(), 3, "keys", 2, false);
+
 var set = new Set();
 set.add(41);
 set.add(42);
@@ -60,3 +89,15 @@ testIteratorMirror(set.entries(), 3, [[o2, o2]]);
 testIteratorMirror(set.keys(), 5, []);
 testIteratorMirror(set.values(), 5, []);
 testIteratorMirror(set.entries(), 5, []);
+
+// Test with maximum limit.
+testIteratorMirror(set.keys(), 1, [42, o1], 2);
+testIteratorMirror(set.values(), 1, [42, o1], 2);
+testIteratorMirror(set.entries(), 1, [[42, 42], [o1, o1]], 2);
+
+testIteratorInternalProperties(set.keys(), 0, "values", 0, true);
+testIteratorInternalProperties(set.values(), 1, "values", 1, true);
+testIteratorInternalProperties(set.entries(), 2, "entries", 2, true);
+testIteratorInternalProperties(set.keys(), 3, "values", 3, true);
+testIteratorInternalProperties(set.values(), 4, "values", 4, false);
+testIteratorInternalProperties(set.entries(), 5, "entries", 4, false);
diff --git a/deps/v8/test/mjsunit/es6/unscopables.js b/deps/v8/test/mjsunit/es6/unscopables.js
index 36365d2d82..03612bec53 100644
--- a/deps/v8/test/mjsunit/es6/unscopables.js
+++ b/deps/v8/test/mjsunit/es6/unscopables.js
@@ -143,6 +143,13 @@ function TestBasics(object) {
     assertEquals(2, y);
     assertEquals(3, z);
   }
+
+  object[Symbol.unscopables] = {x: 0, y: undefined};
+  with (object) {
+    assertEquals(1, x);
+    assertEquals(5, y);
+    assertEquals(3, z);
+  }
 }
 runTest(TestBasics);
 
@@ -161,6 +168,13 @@ function TestUnscopableChain(object) {
   with (object) {
     assertEquals(1, x);
   }
+
+  object[Symbol.unscopables] = {
+    __proto__: {x: undefined}
+  };
+  with (object) {
+    assertEquals(2, x);
+  }
 }
 runTest(TestUnscopableChain);
 
@@ -222,6 +236,14 @@ function TestOnProto(object, proto) {
     assertEquals(5, y);
     assertEquals(3, z);
   }
+
+  proto[Symbol.unscopables] = {y: true};
+  object[Symbol.unscopables] = {x: true, y: undefined};
+  with (object) {
+    assertEquals(1, x);
+    assertEquals(5, y);
+    assertEquals(3, z);
+  }
 }
 runTest(TestOnProto);
 
@@ -341,6 +363,20 @@ function TestChangeDuringWithWithPossibleOptimization4(object) {
 TestChangeDuringWithWithPossibleOptimization4({});
 
 
+function TestChangeDuringWithWithPossibleOptimization4(object) {
+  var x = 1;
+  object.x = 2;
+  object[Symbol.unscopables] = {x: true};
+  with (object) {
+    for (var i = 0; i < 1000; i++) {
+      if (i === 500) object[Symbol.unscopables].x = undefined;
+      assertEquals(i < 500 ? 1 : 2, x);
+    }
+  }
+}
+TestChangeDuringWithWithPossibleOptimization4({});
+
+
 function TestAccessorReceiver(object, proto) {
   var x = 'local';
 
@@ -532,9 +568,11 @@ function TestAccessorOnUnscopables(object) {
   var x = 1;
   object.x = 2;
 
+  var calls = 0;
   var unscopables = {
     get x() {
-      assertUnreachable();
+      calls++;
+      return calls === 1 ? true : undefined;
     }
   };
 
@@ -542,7 +580,9 @@ function TestAccessorOnUnscopables(object) {
     assertEquals(2, x);
     object[Symbol.unscopables] = unscopables;
     assertEquals(1, x);
+    assertEquals(2, x);
   }
+  assertEquals(2, calls);
 }
 runTest(TestAccessorOnUnscopables);
 
@@ -659,3 +699,25 @@ function TestGetUnscopablesGetterThrows() {
   }, CustomError);
 }
 TestGetUnscopablesGetterThrows();
+
+
+function TestGetUnscopablesGetterThrows2() {
+  var object = {
+    get x() {
+      assertUnreachable();
+    }
+  };
+  function CustomError() {}
+
+  object[Symbol.unscopables] = {
+    get x() {
+      throw new CustomError();
+    }
+  };
+  assertThrows(function() {
+    with (object) {
+      x;
+    }
+  }, CustomError);
+}
+TestGetUnscopablesGetterThrows();