| Index: test/mjsunit/random-bit-correlations.js
|
| diff --git a/test/mjsunit/random-bit-correlations.js b/test/mjsunit/random-bit-correlations.js
|
| deleted file mode 100644
|
| index 0561b544ba05d7abc02c70f1e593d77428aa598b..0000000000000000000000000000000000000000
|
| --- a/test/mjsunit/random-bit-correlations.js
|
| +++ /dev/null
|
| @@ -1,69 +0,0 @@
|
| -// 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: --random-seed=12
|
| -
|
| -(function() {
|
| - var kHistory = 2;
|
| - var kRepeats = 100;
|
| - var history = new Uint32Array(kHistory);
|
| -
|
| - function random() {
|
| - return (Math.random() * Math.pow(2, 32)) >>> 0;
|
| - }
|
| -
|
| - function ChiSquared(m, n) {
|
| - var ys_minus_np1 = (m - n / 2.0);
|
| - var chi_squared_1 = ys_minus_np1 * ys_minus_np1 * 2.0 / n;
|
| - var ys_minus_np2 = ((n - m) - n / 2.0);
|
| - var chi_squared_2 = ys_minus_np2 * ys_minus_np2 * 2.0 / n;
|
| - return chi_squared_1 + chi_squared_2;
|
| - }
|
| - for (var predictor_bit = -2; predictor_bit < 32; predictor_bit++) {
|
| - // The predicted bit is one of the bits from the PRNG.
|
| - for (var random_bit = 0; random_bit < 32; random_bit++) {
|
| - for (var ago = 0; ago < kHistory; ago++) {
|
| - // We don't want to check whether each bit predicts itself.
|
| - if (ago == 0 && predictor_bit == random_bit) continue;
|
| - // Enter the new random value into the history
|
| - for (var i = ago; i >= 0; i--) {
|
| - history[i] = random();
|
| - }
|
| - // Find out how many of the bits are the same as the prediction bit.
|
| - var m = 0;
|
| - for (var i = 0; i < kRepeats; i++) {
|
| - for (var j = ago - 1; j >= 0; j--) history[j + 1] = history[j];
|
| - history[0] = random();
|
| - var predicted;
|
| - if (predictor_bit >= 0) {
|
| - predicted = (history[ago] >> predictor_bit) & 1;
|
| - } else {
|
| - predicted = predictor_bit == -2 ? 0 : 1;
|
| - }
|
| - var bit = (history[0] >> random_bit) & 1;
|
| - if (bit == predicted) m++;
|
| - }
|
| - // Chi squared analysis for k = 2 (2, states: same/not-same) and one
|
| - // degree of freedom (k - 1).
|
| - var chi_squared = ChiSquared(m, kRepeats);
|
| - if (chi_squared > 24) {
|
| - var percent = Math.floor(m * 100.0 / kRepeats);
|
| - if (predictor_bit < 0) {
|
| - var bit_value = predictor_bit == -2 ? 0 : 1;
|
| - print(`Bit ${random_bit} is ${bit_value} ${percent}% of the time`);
|
| - } else {
|
| - print(`Bit ${random_bit} is the same as bit ${predictor_bit} ` +
|
| - `${ago} ago ${percent}% of the time`);
|
| - }
|
| - }
|
| - // For 1 degree of freedom this corresponds to 1 in a million. We are
|
| - // running ~8000 tests, so that would be surprising.
|
| - assertTrue(chi_squared <= 24);
|
| - // If the predictor bit is a fixed 0 or 1 then it makes no sense to
|
| - // repeat the test with a different age.
|
| - if (predictor_bit < 0) break;
|
| - }
|
| - }
|
| - }
|
| -})();
|
|
|