1 // Copyright 2013 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 function dead1(a, b) { 29 var x = "a" + "b"; 30 return a; // x, "a", and "b" are dead code 31 } 32 33 function dead2(a, b) { 34 var x = a + "0"; 35 var y = b + "0"; 36 return a; // x and y are both dead 37 } 38 39 function dead3(a, b) { 40 a = a ? "1" : "0"; 41 b = b ? "1" : "0"; 42 var x = a + "0"; 43 var y = b + "0"; 44 return a; // x and y are both dead 45 } 46 47 assertEquals(33, dead1(33, 32)); 48 assertEquals(33, dead2(33, 32)); 49 assertEquals("1", dead3(33, 32)); 50 51 assertEquals(31, dead1(31, 30)); 52 assertEquals(31, dead2(31, 30)); 53 assertEquals("1", dead3(31, 32)); 54 55 assertEquals(0, dead1(0, 30)); 56 assertEquals(0, dead2(0, 30)); 57 assertEquals("0", dead3(0, 32)); 58 59 assertEquals(true, dead1(true, 0)); 60 assertEquals(true, dead2(true, 0)); 61 assertEquals("1", dead3(true, 0)); 62 63 assertEquals("true", dead1("true", 0)); 64 assertEquals("true", dead2("true", 0)); 65 assertEquals("1", dead3("true", 0)); 66