v8/test/mjsunit/undetectable.js

// 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

var obj = %GetUndetectable();

function shouldNotBeTaken() {
  fail("Undetectable branch should not be taken", "branch was taken");
}

function shouldBeTaken() {
  fail("Inverted Undetectable branch should be taken", "branch was not taken");
}

function testCompares() {
  assertTrue(!obj);
  assertFalse(!!obj);
  assertFalse(obj == true);
  assertFalse(obj == false);
  assertFalse(obj === true);
  assertFalse(obj === false);
  assertEquals(2, obj ? 1 : 2);
  assertEquals(obj, true && obj);
  assertEquals(obj, false || obj);
}

function testIfs() {
  if (obj) {
    shouldNotBeTaken();
  }

  if (obj) {
    shouldNotBeTaken();
  } else {
    // do nothing
  }

  if (!obj) {
    // do nothing
  } else {
    shouldBeTaken();
  }
}

function testWhiles() {
  while (obj) {
    shouldNotBeTaken();
  }

  var i = 0;
  while (!obj) {
    i++;
    break;
  }

  assertEquals(1, i);
}

function testFors() {
  for (var i = 0; obj; i++) {
    shouldNotBeTaken();
  }

  var j = 0;
  for (var i = 0; !obj; i++) {
    j++;
    break;
  }

  assertEquals(1, j);
}

for (var j = 0; j < 5; j++) {
  testCompares();
  testIfs();
  testWhiles();
  testFors();

  if (j == 3) {
    %OptimizeFunctionOnNextCall(testCompares);
    %OptimizeFunctionOnNextCall(testIfs);
    %OptimizeFunctionOnNextCall(testWhiles);
    %OptimizeFunctionOnNextCall(testFors);
  }
}