'use strict';
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var GetIntrinsic = require('get-intrinsic');
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var $abs = GetIntrinsic('%Math.abs%');
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var $floor = GetIntrinsic('%Math.floor%');
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var $pow = GetIntrinsic('%Math.pow%');
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var isFinite = require('./isFinite');
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var isNaN = require('./isNaN');
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var isNegativeZero = require('./isNegativeZero');
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var maxFiniteFloat32 = 3.4028234663852886e+38; // roughly 2 ** 128 - 1
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module.exports = function valueToFloat32Bytes(value, isLittleEndian) {
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if (isNaN(value)) {
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return isLittleEndian ? [0, 0, 192, 127] : [127, 192, 0, 0]; // hardcoded
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}
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var leastSig;
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if (value === 0) {
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leastSig = isNegativeZero(value) ? 0x80 : 0;
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return isLittleEndian ? [0, 0, 0, leastSig] : [leastSig, 0, 0, 0];
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}
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if ($abs(value) > maxFiniteFloat32 || !isFinite(value)) {
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leastSig = value < 0 ? 255 : 127;
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return isLittleEndian ? [0, 0, 128, leastSig] : [leastSig, 128, 0, 0];
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}
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var sign = value < 0 ? 1 : 0;
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value = $abs(value); // eslint-disable-line no-param-reassign
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var exponent = 0;
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while (value >= 2) {
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exponent += 1;
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value /= 2; // eslint-disable-line no-param-reassign
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}
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while (value < 1) {
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exponent -= 1;
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value *= 2; // eslint-disable-line no-param-reassign
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}
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var mantissa = value - 1;
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mantissa *= $pow(2, 23) + 0.5;
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mantissa = $floor(mantissa);
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exponent += 127;
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exponent <<= 23;
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var result = (sign << 31)
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| exponent
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| mantissa;
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var byte0 = result & 255;
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result >>= 8;
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var byte1 = result & 255;
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result >>= 8;
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var byte2 = result & 255;
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result >>= 8;
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var byte3 = result & 255;
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if (isLittleEndian) {
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return [byte0, byte1, byte2, byte3];
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}
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return [byte3, byte2, byte1, byte0];
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};
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