doMath.js - mozsearch

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function map_test(t, cases)

  for (var i = 0; i < cases.length; i++) {

    function c() { return t(cases[i].input); }

    var expected = cases[i].expected;

    assertEq(c(), expected);

function lsh_inner(n)

  var r;

  for (var i = 0; i < 35; i++)

    r = 0x1 << n;

  return r;

map_test (lsh_inner,

          [{input: 15, expected: 32768},

           {input: 55, expected: 8388608},

           {input: 1,  expected: 2},

           {input: 0,  expected: 1}]);

function rsh_inner(n)

  var r;

  for (var i = 0; i < 35; i++)

    r = 0x11010101 >> n;

  return r;

map_test (rsh_inner,

          [{input: 8,  expected: 1114369},

           {input: 5,  expected: 8914952},

           {input: 35, expected: 35659808},

           {input: -1, expected: 0}]);

function ursh_inner(n)

  var r;

  for (var i = 0; i < 35; i++)

    r = -55 >>> n;

  return r;

map_test (ursh_inner,

          [{input: 8,  expected: 16777215},

           {input: 33, expected: 2147483620},

           {input: 0,  expected: 4294967241},

           {input: 1,  expected: 2147483620}]);

function doMath_inner(cos)

    var s = 0;

    var sin = Math.sin;

    for (var i = 0; i < 200; i++)

        s = -Math.pow(sin(i) + cos(i * 0.75), 4);

    return s;

function doMath() {

  return doMath_inner(Math.cos);

assertEq(doMath(), -0.5405549555611059);