[builtins] Properly optimize Object.prototype.isPrototypeOf.

test/mjsunit/compiler/object-isprototypeof.js

Index: test/mjsunit/compiler/object-isprototypeof.js
diff --git a/test/mjsunit/compiler/object-isprototypeof.js b/test/mjsunit/compiler/object-isprototypeof.js
new file mode 100644
index 0000000000000000000000000000000000000000..284a4387d60b455c7590122364817dd929f186fd
--- /dev/null
+++ b/test/mjsunit/compiler/object-isprototypeof.js
@@ -0,0 +1,153 @@
+// Copyright 2017 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
+
+// Test corner cases with null/undefined receivers.
+(function() {
+  function foo(x, y) { return Object.prototype.isPrototypeOf.call(x, y); }
+
+  assertThrows(() => foo(null, {}));
+  assertThrows(() => foo(undefined, {}));
+  assertThrows(() => foo(null, []));
+  assertThrows(() => foo(undefined, []));
+  assertFalse(foo(null, 0));
+  assertFalse(foo(undefined, 0));
+  assertFalse(foo(null, ""));
+  assertFalse(foo(undefined, ""));
+  assertFalse(foo(null, null));
+  assertFalse(foo(undefined, null));
+  assertFalse(foo(null, undefined));
+  assertFalse(foo(undefined, undefined));
+  %OptimizeFunctionOnNextCall(foo);
+  assertThrows(() => foo(null, {}));
+  assertThrows(() => foo(undefined, {}));
+  assertThrows(() => foo(null, []));
+  assertThrows(() => foo(undefined, []));
+  assertFalse(foo(null, 0));
+  assertFalse(foo(undefined, 0));
+  assertFalse(foo(null, ""));
+  assertFalse(foo(undefined, ""));
+  assertFalse(foo(null, null));
+  assertFalse(foo(undefined, null));
+  assertFalse(foo(null, undefined));
+  assertFalse(foo(undefined, undefined));
+})();
+
+// Test general constructor prototype case.
+(function() {
+  function A() {}
+  A.prototype = {};
+  var a = new A;
+
+  function foo(x) { return A.prototype.isPrototypeOf(x); }
+
+  assertFalse(foo(0));
+  assertFalse(foo(""));
+  assertFalse(foo(null));
+  assertFalse(foo(undefined));
+  assertFalse(foo({}));
+  assertFalse(foo([]));
+  assertTrue(foo(a));
+  assertTrue(foo(new A));
+  assertTrue(foo({__proto__: a}));
+  assertTrue(foo({__proto__: A.prototype}));
+  %OptimizeFunctionOnNextCall(foo);
+  assertFalse(foo(0));
+  assertFalse(foo(""));
+  assertFalse(foo(null));
+  assertFalse(foo(undefined));
+  assertFalse(foo({}));
+  assertFalse(foo([]));
+  assertTrue(foo(a));
+  assertTrue(foo(new A));
+  assertTrue(foo({__proto__: a}));
+  assertTrue(foo({__proto__: A.prototype}));
+})();
+
+// Test known primitive values.
+(function() {
+  function A() {}
+  A.prototype = {};
+  var a = new A;
+
+  function foo() { return A.prototype.isPrototypeOf(0); }
+
+  assertFalse(foo());
+  assertFalse(foo());
+  %OptimizeFunctionOnNextCall(foo);
+  assertFalse(foo());
+})();
+(function() {
+  function A() {}
+  A.prototype = {};
+  var a = new A;
+
+  function foo() { return A.prototype.isPrototypeOf(null); }
+
+  assertFalse(foo());
+  assertFalse(foo());
+  %OptimizeFunctionOnNextCall(foo);
+  assertFalse(foo());
+})();
+(function() {
+  function A() {}
+  A.prototype = {};
+  var a = new A;
+
+  function foo() { return A.prototype.isPrototypeOf(undefined); }
+
+  assertFalse(foo());
+  assertFalse(foo());
+  %OptimizeFunctionOnNextCall(foo);
+  assertFalse(foo());
+})();
+
+// Test constant-folded prototype chain checks.
+(function() {
+  function A() {}
+  A.prototype = {};
+  var a = new A;
+
+  function foo() { return A.prototype.isPrototypeOf(a); }
+
+  assertTrue(foo());
+  assertTrue(foo());
+  %OptimizeFunctionOnNextCall(foo);
+  assertTrue(foo());
+})();
+(function() {
+  function A() {}
+  var a = new A;
+  A.prototype = {};
+
+  function foo() { return A.prototype.isPrototypeOf(a); }
+
+  assertFalse(foo());
+  assertFalse(foo());
+  %OptimizeFunctionOnNextCall(foo);
+  assertFalse(foo());
+})();
+
+// Test Array prototype chain checks.
+(function() {
+  var a = [];
+
+  function foo() { return Array.prototype.isPrototypeOf(a); }
+
+  assertTrue(foo());
+  assertTrue(foo());
+  %OptimizeFunctionOnNextCall(foo);
+  assertTrue(foo());
+})();
+(function() {
+  var a = [];
+
+  function foo() { return Object.prototype.isPrototypeOf(a); }
+
+  assertTrue(foo());
+  assertTrue(foo());
+  %OptimizeFunctionOnNextCall(foo);
+  assertTrue(foo());
+})();