com.google.javascript.jscomp.js.es6.math.clz32.js Maven / Gradle / Ivy
/*
* Copyright 2016 The Closure Compiler Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'require util/polyfill';
$jscomp.polyfill('Math.clz32', function(orig) {
if (orig) return orig;
/**
* Counts the leading zeros in the 32-bit binary representation.
*
* Polyfills the static function Math.clz32().
*
* @param {number} x Any number, or value that can be coerced to a number.
* @return {number} The number of leading zero bits.
*/
var polyfill = function(x) {
// This binary search algorithm is taken from v8.
x = Number(x) >>> 0; // first ensure we have a 32-bit unsigned integer.
if (x === 0) return 32;
var result = 0;
if ((x & 0xFFFF0000) === 0) {
x <<= 16;
result += 16;
}
if ((x & 0xFF000000) === 0) {
x <<= 8;
result += 8;
}
if ((x & 0xF0000000) === 0) {
x <<= 4;
result += 4;
}
if ((x & 0xC0000000) === 0) {
x <<= 2;
result += 2;
}
if ((x & 0x80000000) === 0) result++;
return result;
};
return polyfill;
}, 'es6', 'es3');