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// Copyright 2012 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.
(function(global, utils) {
"use strict";
%CheckIsBootstrapping();
// -------------------------------------------------------------------
// Imports
// The first two slots are reserved to persist PRNG state.
define kRandomNumberStart = 2;
var GlobalMath = global.Math;
var NaN = %GetRootNaN();
var nextRandomIndex = 0;
var randomNumbers = UNDEFINED;
var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
//-------------------------------------------------------------------
// ECMA 262 - 15.8.2.14
function MathRandom() {
// While creating a startup snapshot, %GenerateRandomNumbers returns a
// normal array containing a single random number, and has to be called for
// every new random number.
// Otherwise, it returns a pre-populated typed array of random numbers. The
// first two elements are reserved for the PRNG state.
if (nextRandomIndex <= kRandomNumberStart) {
randomNumbers = %GenerateRandomNumbers(randomNumbers);
if (%_IsTypedArray(randomNumbers)) {
nextRandomIndex = %_TypedArrayGetLength(randomNumbers);
} else {
nextRandomIndex = randomNumbers.length;
}
}
return randomNumbers[--nextRandomIndex];
}
// -------------------------------------------------------------------
%AddNamedProperty(GlobalMath, toStringTagSymbol, "Math", READ_ONLY | DONT_ENUM);
// Set up non-enumerable functions of the Math object and
// set their names.
utils.InstallFunctions(GlobalMath, DONT_ENUM, [
"random", MathRandom,
]);
%SetForceInlineFlag(MathRandom);
// -------------------------------------------------------------------
// Exports
utils.Export(function(to) {
to.MathRandom = MathRandom;
});
})
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