Cross-script variables handling fixed. It was possible to write to read-only global variable.

test/mjsunit/regress/cross-script-vars.js

Index: test/mjsunit/regress/cross-script-vars.js
diff --git a/test/mjsunit/regress/cross-script-vars.js b/test/mjsunit/regress/cross-script-vars.js
new file mode 100644
index 0000000000000000000000000000000000000000..24e53368cb9e1162250e4fc60f1740eeccbcd389
--- /dev/null
+++ b/test/mjsunit/regress/cross-script-vars.js
@@ -0,0 +1,573 @@
+// Copyright 2015 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
+
+function PrintDesc(desc, s) {
+  var json;
+  if (desc) {
+    json = JSON.stringify(desc);
+  } else {
+    json = "<no such property>";
+  }
+  if (s === undefined) {
+    print(json);
+  } else {
+    print(s + ": " + json);
+  }
+}
+
+
+var counters;
+var test_realm;
+var cfg;
+
+
+function GetDescriptor() {
+  var code = 'Object.getOwnPropertyDescriptor(global, "x")';
+  var desc = Realm.eval(test_realm, code);
+//  PrintDesc(desc);
+  return desc;
+}
+
+function SetUp() {
+  counters = {};
+  Realm.shared = {counters: counters};
+  test_realm = Realm.create();
+  Realm.eval(test_realm, 'var global = Realm.global(Realm.current());');
+  print("=====================");
+  print("Test realm: " + test_realm);
+  assertEquals(undefined, GetDescriptor());
+}
+
+function TearDown() {
+  Realm.dispose(test_realm);
+  print("OK");
+}
+
+
+function AddStrict(code, cfg) {
+  return cfg.strict ? '"use strict"; ' + code : code;
+}
+
+function ForceMutablePropertyCellType() {
+  Realm.eval(test_realm, 'global.x = {}; global.x = undefined;');
+}
+
+function DeclareVar() {
+  var code = 'var x;';
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function DefineVar(v) {
+  var code = 'var x = ' + v;
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function DefineLoadVar() {
+  var name = 'LoadVar_' + test_realm;
+  var code =
+      'var x;' +
+      'function ' + name + '() {' +
+      '  return x;' +
+      '};';
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function LoadVar() {
+  var name = 'LoadVar_' + test_realm;
+  var code =
+      (cfg.optimize ? '%OptimizeFunctionOnNextCall(' + name + ');' : '') +
+      name + '();';
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function DefineStoreVar() {
+  var name = 'StoreVar_' + test_realm;
+  var code = 'var g = (Function("return this"))();' +
+      'var x;' +
+      'function ' + name + '(v) {' +
+//      '  %DebugPrint(g);' +
+      '  return x = v;' +
+      '};';
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function StoreVar(v) {
+  var name = 'StoreVar_' + test_realm;
+  var code =
+      (cfg.optimize ? '%OptimizeFunctionOnNextCall(' + name + ');' : '') +
+      name + '(' + v + ');';
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+// It does 13 iterations which results in 27 loads
+// and 14 stores.
+function LoadStoreLoop() {
+  var code = 'for(var x = 0; x < 13; x++);';
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function DefineRWDataProperty() {
+  var code =
+      'Object.defineProperty(global, "x", { ' +
+      '  value: 42, ' +
+      '  writable: true, ' +
+      '  enumerable: true, ' +
+      '  configurable: true ' +
+      '});';
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function DefineRODataProperty() {
+  var code =
+      'Object.defineProperty(global, "x", { ' +
+      '  value: 42, ' +
+      '  writable: false, ' +
+      '  enumerable: true, ' +
+      '  configurable: true ' +
+      '});';
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function SetX_(v) {
+  var code =
+      'global.x_ = ' + v + '; ';
+  return Realm.eval(test_realm, code);
+}
+
+function DefineRWAccessorProperty() {
+  var code =
+      'Object.defineProperty(global, "x", {' +
+      '  get: function() { Realm.shared.counters.get_count++; return this.x_; },' +
+      '  set: function(v) { Realm.shared.counters.set_count++; this.x_ = v; },' +
+      '  enumerable: true, configurable: true' +
+      '});';
+  counters.get_count = 0;
+  counters.set_count = 0;
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+function DefineROAccessorProperty() {
+  var code =
+      'Object.defineProperty(global, "x", {' +
+      '  get: function() { Realm.shared.counters.get_count++; return this.x_; },' +
+      '  enumerable: true, configurable: true' +
+      '});';
+  counters.get_count = 0;
+  counters.set_count = 0;
+  return Realm.eval(test_realm, AddStrict(code, cfg));
+}
+
+
+function testSuite(opt_cfg) {
+  //
+  // Non strict.
+  //
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: false};
+    DeclareVar();
+    DefineLoadVar();
+    DefineStoreVar();
+    assertEquals(undefined, LoadVar());
+    assertEquals(false, GetDescriptor().configurable);
+
+    // Force property cell type to kMutable.
+    DefineVar(undefined);
+    DefineVar(153);
+    assertEquals(false, GetDescriptor().configurable);
+
+    assertEquals(153, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(113, LoadVar());
+    LoadStoreLoop();
+    assertEquals(13, LoadVar());
+    TearDown();
+  })();
+
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: false};
+    ForceMutablePropertyCellType();
+    DefineLoadVar();
+    DefineStoreVar();
+    DefineRWDataProperty();
+    assertEquals(42, LoadVar());
+    assertEquals(true, GetDescriptor().configurable);
+
+    DefineVar(153);
+    assertEquals(true, GetDescriptor().configurable);
+
+    assertEquals(153, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(113, LoadVar());
+    LoadStoreLoop();
+    assertEquals(13, LoadVar());
+
+    // Now reconfigure to accessor.
+    DefineRWAccessorProperty();
+    assertEquals(undefined, GetDescriptor().value);
+    assertEquals(true, GetDescriptor().configurable);
+    assertEquals(0, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(undefined, LoadVar());
+    assertEquals(1, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    LoadStoreLoop();
+    assertEquals(28, counters.get_count);
+    assertEquals(14, counters.set_count);
+
+    assertEquals(13, LoadVar());
+    assertEquals(29, counters.get_count);
+    assertEquals(14, counters.set_count);
+
+    TearDown();
+  })();
+
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: false};
+    ForceMutablePropertyCellType();
+    DefineLoadVar();
+    DefineStoreVar();
+    DefineRODataProperty();
+    assertEquals(42, LoadVar());
+    assertEquals(true, GetDescriptor().configurable);
+
+    DefineVar(153);
+
+    assertEquals(42, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(42, LoadVar());
+    LoadStoreLoop();
+    assertEquals(42, LoadVar());
+
+    // Now reconfigure to accessor property.
+    DefineRWAccessorProperty();
+    assertEquals(undefined, GetDescriptor().value);
+    assertEquals(true, GetDescriptor().configurable);
+    assertEquals(0, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(undefined, LoadVar());
+    assertEquals(1, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    LoadStoreLoop();
+    assertEquals(28, counters.get_count);
+    assertEquals(14, counters.set_count);
+
+    assertEquals(13, LoadVar());
+    assertEquals(29, counters.get_count);
+    assertEquals(14, counters.set_count);
+
+    TearDown();
+  })();
+
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: false};
+    ForceMutablePropertyCellType();
+    DefineLoadVar();
+    DefineStoreVar();
+    DefineRWAccessorProperty();
+    assertEquals(0, counters.get_count);
+    assertEquals(0, counters.set_count);
+    assertEquals(true, GetDescriptor().configurable);
+
+    assertEquals(undefined, LoadVar());
+    assertEquals(1, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    DefineVar(153);
+    assertEquals(true, GetDescriptor().configurable);
+    assertEquals(1, counters.get_count);
+    assertEquals(1, counters.set_count);
+
+    assertEquals(153, LoadVar());
+    assertEquals(2, counters.get_count);
+    assertEquals(1, counters.set_count);
+
+    assertEquals(113, StoreVar(113));
+    assertEquals(2, counters.get_count);
+    assertEquals(2, counters.set_count);
+
+    assertEquals(113, LoadVar());
+    assertEquals(3, counters.get_count);
+    assertEquals(2, counters.set_count);
+
+    LoadStoreLoop();
+    assertEquals(30, counters.get_count);
+    assertEquals(16, counters.set_count);
+
+    assertEquals(13, LoadVar());
+    assertEquals(31, counters.get_count);
+    assertEquals(16, counters.set_count);
+
+    // Now reconfigure to data property.
+    DefineRWDataProperty();
+    assertEquals(42, GetDescriptor().value);
+    assertEquals(42, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(31, counters.get_count);
+    assertEquals(16, counters.set_count);
+
+    TearDown();
+  })();
+
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: false};
+    ForceMutablePropertyCellType();
+    DefineLoadVar();
+    DefineStoreVar();
+    DefineROAccessorProperty();
+    assertEquals(0, counters.get_count);
+    assertEquals(0, counters.set_count);
+    assertEquals(true, GetDescriptor().configurable);
+
+    assertEquals(undefined, LoadVar());
+    assertEquals(1, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    SetX_(42);
+    assertEquals(42, LoadVar());
+    assertEquals(2, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    DefineVar(153);
+    assertEquals(true, GetDescriptor().configurable);
+    assertEquals(2, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(42, LoadVar());
+    assertEquals(3, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(113, StoreVar(113));
+    assertEquals(3, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(42, LoadVar());
+    assertEquals(4, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    LoadStoreLoop();
+    assertEquals(5, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(42, LoadVar());
+    assertEquals(6, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    // Now reconfigure to data property.
+    DefineRWDataProperty();
+    assertEquals(42, GetDescriptor().value);
+    assertEquals(42, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(6, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    TearDown();
+  })();
+
+
+  //
+  // Strict.
+  //
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: true};
+    DeclareVar();
+    DefineLoadVar();
+    DefineStoreVar();
+    assertEquals(undefined, LoadVar());
+    assertEquals(false, GetDescriptor().configurable);
+
+    // Force property cell type to kMutable.
+    DefineVar(undefined);
+    DefineVar(153);
+    assertEquals(false, GetDescriptor().configurable);
+
+    assertEquals(153, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(113, LoadVar());
+    LoadStoreLoop();
+    assertEquals(13, LoadVar());
+    TearDown();
+  })();
+
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: true};
+    ForceMutablePropertyCellType();
+    DefineLoadVar();
+    DefineStoreVar();
+    DefineRWDataProperty();
+    assertEquals(42, LoadVar());
+    assertEquals(true, GetDescriptor().configurable);
+
+    DefineVar(153);
+    assertEquals(true, GetDescriptor().configurable);
+
+    assertEquals(153, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(113, LoadVar());
+    LoadStoreLoop();
+    assertEquals(13, LoadVar());
+    TearDown();
+  })();
+
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: true};
+    ForceMutablePropertyCellType();
+    DefineLoadVar();
+    DefineStoreVar();
+    DefineRWDataProperty();
+    assertEquals(true, GetDescriptor().configurable);
+    assertEquals(true, GetDescriptor().writable);
+    assertEquals(113, StoreVar(113));
+
+    DefineRODataProperty();
+    assertEquals(true, GetDescriptor().configurable);
+    assertEquals(false, GetDescriptor().writable);
+
+    assertEquals(42, LoadVar());
+    assertEquals(true, GetDescriptor().configurable);
+    assertThrows('DefineVar(153)');
+    assertEquals(42, LoadVar());
+    assertThrows('StoreVar(113)');
+    assertThrows('StoreVar(113)');
+    assertEquals(42, LoadVar());
+    assertThrows('LoadStoreLoop()');
+    assertEquals(42, LoadVar());
+    TearDown();
+  })();
+
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: true};
+    ForceMutablePropertyCellType();
+    DefineLoadVar();
+    DefineStoreVar();
+    DefineRWAccessorProperty();
+    assertEquals(0, counters.get_count);
+    assertEquals(0, counters.set_count);
+    assertEquals(true, GetDescriptor().configurable);
+
+    assertEquals(undefined, LoadVar());
+    assertEquals(1, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    DefineVar(153);
+    assertEquals(true, GetDescriptor().configurable);
+    assertEquals(1, counters.get_count);
+    assertEquals(1, counters.set_count);
+
+    assertEquals(153, LoadVar());
+    assertEquals(2, counters.get_count);
+    assertEquals(1, counters.set_count);
+
+    assertEquals(113, StoreVar(113));
+    assertEquals(2, counters.get_count);
+    assertEquals(2, counters.set_count);
+
+    assertEquals(113, LoadVar());
+    assertEquals(3, counters.get_count);
+    assertEquals(2, counters.set_count);
+
+    LoadStoreLoop();
+    assertEquals(30, counters.get_count);
+    assertEquals(16, counters.set_count);
+
+    assertEquals(13, LoadVar());
+    assertEquals(31, counters.get_count);
+    assertEquals(16, counters.set_count);
+
+    // Now reconfigure to data property.
+    DefineRWDataProperty();
+    assertEquals(42, GetDescriptor().value);
+    assertEquals(42, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(31, counters.get_count);
+    assertEquals(16, counters.set_count);
+
+    TearDown();
+  })();
+
+
+  (function() {
+    SetUp();
+    cfg = {optimize: opt_cfg.optimize, strict: true};
+    ForceMutablePropertyCellType();
+    DefineLoadVar();
+    DefineStoreVar();
+    DefineROAccessorProperty();
+    assertEquals(0, counters.get_count);
+    assertEquals(0, counters.set_count);
+    assertEquals(true, GetDescriptor().configurable);
+
+    assertEquals(undefined, LoadVar());
+    assertEquals(1, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    SetX_(42);
+    assertEquals(42, LoadVar());
+    assertEquals(2, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertThrows('DefineVar(153)');
+    assertEquals(true, GetDescriptor().configurable);
+    assertEquals(2, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(42, LoadVar());
+    assertEquals(3, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertThrows('StoreVar(113)');
+    assertEquals(3, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(42, LoadVar());
+    assertEquals(4, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertThrows('LoadStoreLoop()');
+    assertEquals(4, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    assertEquals(42, LoadVar());
+    assertEquals(5, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    // Now reconfigure to data property.
+    DefineRWDataProperty();
+    assertEquals(42, GetDescriptor().value);
+    assertEquals(42, LoadVar());
+    assertEquals(113, StoreVar(113));
+    assertEquals(5, counters.get_count);
+    assertEquals(0, counters.set_count);
+
+    TearDown();
+  })();
+
+}  // testSuite
+
+
+testSuite({optimize: false});
+testSuite({optimize: true});