src/v8/test/mjsunit/compiler/dead-code.js

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function dead1(a, b) {
    var x = a + b;
    return a; // x is dead
}

function dead2(a, b) {
    var x = a | 0;
    var y = b | 0;
    return a; // x and y are both dead
}

function dead3(a, b) {
    var z;
    if(a == 2) z = a;
    else z = b;
    return a; // z is dead
}

function dead4(a) {
    var z = 3;
    for (i = 0; i < 3; i++) {
        z++;
    }
    return a; // z is dead
}

function dead5(a) {
    var z = 3;
    for (i = 0; i < 3; i++) {
        z++;
    }
    var w = z + a;
    return a; // z is dead
}

assertTrue(dead1(33, 32) == 33);
assertTrue(dead2(33, 32) == 33);
assertTrue(dead3(33, 32) == 33);
assertTrue(dead4(33) == 33);
assertTrue(dead5(33) == 33);

assertTrue(dead1(34, 7) == 34);
assertTrue(dead2(34, 7) == 34);
assertTrue(dead3(34, 7) == 34);
assertTrue(dead4(34) == 34);
assertTrue(dead5(34) == 34);

assertTrue(dead1(3.4, 0.1) == 3.4);
assertTrue(dead2(3.4, 0.1) == 3.4);
assertTrue(dead3(3.4, 0.1) == 3.4);
assertTrue(dead4(3.4) == 3.4);
assertTrue(dead5(3.4) == 3.4);