diff options
author | Alon Zakai <alonzakai@gmail.com> | 2012-04-01 11:19:54 -0700 |
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committer | Alon Zakai <alonzakai@gmail.com> | 2012-04-01 11:19:54 -0700 |
commit | e1a210f81387d60b3bd75954e76f243bce33068b (patch) | |
tree | 0736e22cc08dfdb13fc85f3dd82c871050d3e6aa /src/long.js | |
parent | 51a9dde3da7b14d3deecb79bd879194644335aae (diff) |
add closure compiler long/i64 library
Diffstat (limited to 'src/long.js')
-rw-r--r-- | src/long.js | 801 |
1 files changed, 801 insertions, 0 deletions
diff --git a/src/long.js b/src/long.js new file mode 100644 index 00000000..f03e5fa5 --- /dev/null +++ b/src/long.js @@ -0,0 +1,801 @@ +// Copyright 2009 The Closure Library Authors. All Rights Reserved. +// +// 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. + +/** + * @fileoverview Defines a Long class for representing a 64-bit two's-complement + * integer value, which faithfully simulates the behavior of a Java "long". This + * implementation is derived from LongLib in GWT. + * + */ + +goog.provide('goog.math.Long'); + + + +/** + * Constructs a 64-bit two's-complement integer, given its low and high 32-bit + * values as *signed* integers. See the from* functions below for more + * convenient ways of constructing Longs. + * + * The internal representation of a long is the two given signed, 32-bit values. + * We use 32-bit pieces because these are the size of integers on which + * Javascript performs bit-operations. For operations like addition and + * multiplication, we split each number into 16-bit pieces, which can easily be + * multiplied within Javascript's floating-point representation without overflow + * or change in sign. + * + * In the algorithms below, we frequently reduce the negative case to the + * positive case by negating the input(s) and then post-processing the result. + * Note that we must ALWAYS check specially whether those values are MIN_VALUE + * (-2^63) because -MIN_VALUE == MIN_VALUE (since 2^63 cannot be represented as + * a positive number, it overflows back into a negative). Not handling this + * case would often result in infinite recursion. + * + * @param {number} low The low (signed) 32 bits of the long. + * @param {number} high The high (signed) 32 bits of the long. + * @constructor + */ +goog.math.Long = function(low, high) { + /** + * @type {number} + * @private + */ + this.low_ = low | 0; // force into 32 signed bits. + + /** + * @type {number} + * @private + */ + this.high_ = high | 0; // force into 32 signed bits. +}; + + +// NOTE: Common constant values ZERO, ONE, NEG_ONE, etc. are defined below the +// from* methods on which they depend. + + +/** + * A cache of the Long representations of small integer values. + * @type {!Object} + * @private + */ +goog.math.Long.IntCache_ = {}; + + +/** + * Returns a Long representing the given (32-bit) integer value. + * @param {number} value The 32-bit integer in question. + * @return {!goog.math.Long} The corresponding Long value. + */ +goog.math.Long.fromInt = function(value) { + if (-128 <= value && value < 128) { + var cachedObj = goog.math.Long.IntCache_[value]; + if (cachedObj) { + return cachedObj; + } + } + + var obj = new goog.math.Long(value | 0, value < 0 ? -1 : 0); + if (-128 <= value && value < 128) { + goog.math.Long.IntCache_[value] = obj; + } + return obj; +}; + + +/** + * Returns a Long representing the given value, provided that it is a finite + * number. Otherwise, zero is returned. + * @param {number} value The number in question. + * @return {!goog.math.Long} The corresponding Long value. + */ +goog.math.Long.fromNumber = function(value) { + if (isNaN(value) || !isFinite(value)) { + return goog.math.Long.ZERO; + } else if (value <= -goog.math.Long.TWO_PWR_63_DBL_) { + return goog.math.Long.MIN_VALUE; + } else if (value + 1 >= goog.math.Long.TWO_PWR_63_DBL_) { + return goog.math.Long.MAX_VALUE; + } else if (value < 0) { + return goog.math.Long.fromNumber(-value).negate(); + } else { + return new goog.math.Long( + (value % goog.math.Long.TWO_PWR_32_DBL_) | 0, + (value / goog.math.Long.TWO_PWR_32_DBL_) | 0); + } +}; + + +/** + * Returns a Long representing the 64-bit integer that comes by concatenating + * the given high and low bits. Each is assumed to use 32 bits. + * @param {number} lowBits The low 32-bits. + * @param {number} highBits The high 32-bits. + * @return {!goog.math.Long} The corresponding Long value. + */ +goog.math.Long.fromBits = function(lowBits, highBits) { + return new goog.math.Long(lowBits, highBits); +}; + + +/** + * Returns a Long representation of the given string, written using the given + * radix. + * @param {string} str The textual representation of the Long. + * @param {number=} opt_radix The radix in which the text is written. + * @return {!goog.math.Long} The corresponding Long value. + */ +goog.math.Long.fromString = function(str, opt_radix) { + if (str.length == 0) { + throw Error('number format error: empty string'); + } + + var radix = opt_radix || 10; + if (radix < 2 || 36 < radix) { + throw Error('radix out of range: ' + radix); + } + + if (str.charAt(0) == '-') { + return goog.math.Long.fromString(str.substring(1), radix).negate(); + } else if (str.indexOf('-') >= 0) { + throw Error('number format error: interior "-" character: ' + str); + } + + // Do several (8) digits each time through the loop, so as to + // minimize the calls to the very expensive emulated div. + var radixToPower = goog.math.Long.fromNumber(Math.pow(radix, 8)); + + var result = goog.math.Long.ZERO; + for (var i = 0; i < str.length; i += 8) { + var size = Math.min(8, str.length - i); + var value = parseInt(str.substring(i, i + size), radix); + if (size < 8) { + var power = goog.math.Long.fromNumber(Math.pow(radix, size)); + result = result.multiply(power).add(goog.math.Long.fromNumber(value)); + } else { + result = result.multiply(radixToPower); + result = result.add(goog.math.Long.fromNumber(value)); + } + } + return result; +}; + + +// NOTE: the compiler should inline these constant values below and then remove +// these variables, so there should be no runtime penalty for these. + + +/** + * Number used repeated below in calculations. This must appear before the + * first call to any from* function below. + * @type {number} + * @private + */ +goog.math.Long.TWO_PWR_16_DBL_ = 1 << 16; + + +/** + * @type {number} + * @private + */ +goog.math.Long.TWO_PWR_24_DBL_ = 1 << 24; + + +/** + * @type {number} + * @private + */ +goog.math.Long.TWO_PWR_32_DBL_ = + goog.math.Long.TWO_PWR_16_DBL_ * goog.math.Long.TWO_PWR_16_DBL_; + + +/** + * @type {number} + * @private + */ +goog.math.Long.TWO_PWR_31_DBL_ = + goog.math.Long.TWO_PWR_32_DBL_ / 2; + + +/** + * @type {number} + * @private + */ +goog.math.Long.TWO_PWR_48_DBL_ = + goog.math.Long.TWO_PWR_32_DBL_ * goog.math.Long.TWO_PWR_16_DBL_; + + +/** + * @type {number} + * @private + */ +goog.math.Long.TWO_PWR_64_DBL_ = + goog.math.Long.TWO_PWR_32_DBL_ * goog.math.Long.TWO_PWR_32_DBL_; + + +/** + * @type {number} + * @private + */ +goog.math.Long.TWO_PWR_63_DBL_ = + goog.math.Long.TWO_PWR_64_DBL_ / 2; + + +/** @type {!goog.math.Long} */ +goog.math.Long.ZERO = goog.math.Long.fromInt(0); + + +/** @type {!goog.math.Long} */ +goog.math.Long.ONE = goog.math.Long.fromInt(1); + + +/** @type {!goog.math.Long} */ +goog.math.Long.NEG_ONE = goog.math.Long.fromInt(-1); + + +/** @type {!goog.math.Long} */ +goog.math.Long.MAX_VALUE = + goog.math.Long.fromBits(0xFFFFFFFF | 0, 0x7FFFFFFF | 0); + + +/** @type {!goog.math.Long} */ +goog.math.Long.MIN_VALUE = goog.math.Long.fromBits(0, 0x80000000 | 0); + + +/** + * @type {!goog.math.Long} + * @private + */ +goog.math.Long.TWO_PWR_24_ = goog.math.Long.fromInt(1 << 24); + + +/** @return {number} The value, assuming it is a 32-bit integer. */ +goog.math.Long.prototype.toInt = function() { + return this.low_; +}; + + +/** @return {number} The closest floating-point representation to this value. */ +goog.math.Long.prototype.toNumber = function() { + return this.high_ * goog.math.Long.TWO_PWR_32_DBL_ + + this.getLowBitsUnsigned(); +}; + + +/** + * @param {number=} opt_radix The radix in which the text should be written. + * @return {string} The textual representation of this value. + */ +goog.math.Long.prototype.toString = function(opt_radix) { + var radix = opt_radix || 10; + if (radix < 2 || 36 < radix) { + throw Error('radix out of range: ' + radix); + } + + if (this.isZero()) { + return '0'; + } + + if (this.isNegative()) { + if (this.equals(goog.math.Long.MIN_VALUE)) { + // We need to change the Long value before it can be negated, so we remove + // the bottom-most digit in this base and then recurse to do the rest. + var radixLong = goog.math.Long.fromNumber(radix); + var div = this.div(radixLong); + var rem = div.multiply(radixLong).subtract(this); + return div.toString(radix) + rem.toInt().toString(radix); + } else { + return '-' + this.negate().toString(radix); + } + } + + // Do several (6) digits each time through the loop, so as to + // minimize the calls to the very expensive emulated div. + var radixToPower = goog.math.Long.fromNumber(Math.pow(radix, 6)); + + var rem = this; + var result = ''; + while (true) { + var remDiv = rem.div(radixToPower); + var intval = rem.subtract(remDiv.multiply(radixToPower)).toInt(); + var digits = intval.toString(radix); + + rem = remDiv; + if (rem.isZero()) { + return digits + result; + } else { + while (digits.length < 6) { + digits = '0' + digits; + } + result = '' + digits + result; + } + } +}; + + +/** @return {number} The high 32-bits as a signed value. */ +goog.math.Long.prototype.getHighBits = function() { + return this.high_; +}; + + +/** @return {number} The low 32-bits as a signed value. */ +goog.math.Long.prototype.getLowBits = function() { + return this.low_; +}; + + +/** @return {number} The low 32-bits as an unsigned value. */ +goog.math.Long.prototype.getLowBitsUnsigned = function() { + return (this.low_ >= 0) ? + this.low_ : goog.math.Long.TWO_PWR_32_DBL_ + this.low_; +}; + + +/** + * @return {number} Returns the number of bits needed to represent the absolute + * value of this Long. + */ +goog.math.Long.prototype.getNumBitsAbs = function() { + if (this.isNegative()) { + if (this.equals(goog.math.Long.MIN_VALUE)) { + return 64; + } else { + return this.negate().getNumBitsAbs(); + } + } else { + var val = this.high_ != 0 ? this.high_ : this.low_; + for (var bit = 31; bit > 0; bit--) { + if ((val & (1 << bit)) != 0) { + break; + } + } + return this.high_ != 0 ? bit + 33 : bit + 1; + } +}; + + +/** @return {boolean} Whether this value is zero. */ +goog.math.Long.prototype.isZero = function() { + return this.high_ == 0 && this.low_ == 0; +}; + + +/** @return {boolean} Whether this value is negative. */ +goog.math.Long.prototype.isNegative = function() { + return this.high_ < 0; +}; + + +/** @return {boolean} Whether this value is odd. */ +goog.math.Long.prototype.isOdd = function() { + return (this.low_ & 1) == 1; +}; + + +/** + * @param {goog.math.Long} other Long to compare against. + * @return {boolean} Whether this Long equals the other. + */ +goog.math.Long.prototype.equals = function(other) { + return (this.high_ == other.high_) && (this.low_ == other.low_); +}; + + +/** + * @param {goog.math.Long} other Long to compare against. + * @return {boolean} Whether this Long does not equal the other. + */ +goog.math.Long.prototype.notEquals = function(other) { + return (this.high_ != other.high_) || (this.low_ != other.low_); +}; + + +/** + * @param {goog.math.Long} other Long to compare against. + * @return {boolean} Whether this Long is less than the other. + */ +goog.math.Long.prototype.lessThan = function(other) { + return this.compare(other) < 0; +}; + + +/** + * @param {goog.math.Long} other Long to compare against. + * @return {boolean} Whether this Long is less than or equal to the other. + */ +goog.math.Long.prototype.lessThanOrEqual = function(other) { + return this.compare(other) <= 0; +}; + + +/** + * @param {goog.math.Long} other Long to compare against. + * @return {boolean} Whether this Long is greater than the other. + */ +goog.math.Long.prototype.greaterThan = function(other) { + return this.compare(other) > 0; +}; + + +/** + * @param {goog.math.Long} other Long to compare against. + * @return {boolean} Whether this Long is greater than or equal to the other. + */ +goog.math.Long.prototype.greaterThanOrEqual = function(other) { + return this.compare(other) >= 0; +}; + + +/** + * Compares this Long with the given one. + * @param {goog.math.Long} other Long to compare against. + * @return {number} 0 if they are the same, 1 if the this is greater, and -1 + * if the given one is greater. + */ +goog.math.Long.prototype.compare = function(other) { + if (this.equals(other)) { + return 0; + } + + var thisNeg = this.isNegative(); + var otherNeg = other.isNegative(); + if (thisNeg && !otherNeg) { + return -1; + } + if (!thisNeg && otherNeg) { + return 1; + } + + // at this point, the signs are the same, so subtraction will not overflow + if (this.subtract(other).isNegative()) { + return -1; + } else { + return 1; + } +}; + + +/** @return {!goog.math.Long} The negation of this value. */ +goog.math.Long.prototype.negate = function() { + if (this.equals(goog.math.Long.MIN_VALUE)) { + return goog.math.Long.MIN_VALUE; + } else { + return this.not().add(goog.math.Long.ONE); + } +}; + + +/** + * Returns the sum of this and the given Long. + * @param {goog.math.Long} other Long to add to this one. + * @return {!goog.math.Long} The sum of this and the given Long. + */ +goog.math.Long.prototype.add = function(other) { + // Divide each number into 4 chunks of 16 bits, and then sum the chunks. + + var a48 = this.high_ >>> 16; + var a32 = this.high_ & 0xFFFF; + var a16 = this.low_ >>> 16; + var a00 = this.low_ & 0xFFFF; + + var b48 = other.high_ >>> 16; + var b32 = other.high_ & 0xFFFF; + var b16 = other.low_ >>> 16; + var b00 = other.low_ & 0xFFFF; + + var c48 = 0, c32 = 0, c16 = 0, c00 = 0; + c00 += a00 + b00; + c16 += c00 >>> 16; + c00 &= 0xFFFF; + c16 += a16 + b16; + c32 += c16 >>> 16; + c16 &= 0xFFFF; + c32 += a32 + b32; + c48 += c32 >>> 16; + c32 &= 0xFFFF; + c48 += a48 + b48; + c48 &= 0xFFFF; + return goog.math.Long.fromBits((c16 << 16) | c00, (c48 << 16) | c32); +}; + + +/** + * Returns the difference of this and the given Long. + * @param {goog.math.Long} other Long to subtract from this. + * @return {!goog.math.Long} The difference of this and the given Long. + */ +goog.math.Long.prototype.subtract = function(other) { + return this.add(other.negate()); +}; + + +/** + * Returns the product of this and the given long. + * @param {goog.math.Long} other Long to multiply with this. + * @return {!goog.math.Long} The product of this and the other. + */ +goog.math.Long.prototype.multiply = function(other) { + if (this.isZero()) { + return goog.math.Long.ZERO; + } else if (other.isZero()) { + return goog.math.Long.ZERO; + } + + if (this.equals(goog.math.Long.MIN_VALUE)) { + return other.isOdd() ? goog.math.Long.MIN_VALUE : goog.math.Long.ZERO; + } else if (other.equals(goog.math.Long.MIN_VALUE)) { + return this.isOdd() ? goog.math.Long.MIN_VALUE : goog.math.Long.ZERO; + } + + if (this.isNegative()) { + if (other.isNegative()) { + return this.negate().multiply(other.negate()); + } else { + return this.negate().multiply(other).negate(); + } + } else if (other.isNegative()) { + return this.multiply(other.negate()).negate(); + } + + // If both longs are small, use float multiplication + if (this.lessThan(goog.math.Long.TWO_PWR_24_) && + other.lessThan(goog.math.Long.TWO_PWR_24_)) { + return goog.math.Long.fromNumber(this.toNumber() * other.toNumber()); + } + + // Divide each long into 4 chunks of 16 bits, and then add up 4x4 products. + // We can skip products that would overflow. + + var a48 = this.high_ >>> 16; + var a32 = this.high_ & 0xFFFF; + var a16 = this.low_ >>> 16; + var a00 = this.low_ & 0xFFFF; + + var b48 = other.high_ >>> 16; + var b32 = other.high_ & 0xFFFF; + var b16 = other.low_ >>> 16; + var b00 = other.low_ & 0xFFFF; + + var c48 = 0, c32 = 0, c16 = 0, c00 = 0; + c00 += a00 * b00; + c16 += c00 >>> 16; + c00 &= 0xFFFF; + c16 += a16 * b00; + c32 += c16 >>> 16; + c16 &= 0xFFFF; + c16 += a00 * b16; + c32 += c16 >>> 16; + c16 &= 0xFFFF; + c32 += a32 * b00; + c48 += c32 >>> 16; + c32 &= 0xFFFF; + c32 += a16 * b16; + c48 += c32 >>> 16; + c32 &= 0xFFFF; + c32 += a00 * b32; + c48 += c32 >>> 16; + c32 &= 0xFFFF; + c48 += a48 * b00 + a32 * b16 + a16 * b32 + a00 * b48; + c48 &= 0xFFFF; + return goog.math.Long.fromBits((c16 << 16) | c00, (c48 << 16) | c32); +}; + + +/** + * Returns this Long divided by the given one. + * @param {goog.math.Long} other Long by which to divide. + * @return {!goog.math.Long} This Long divided by the given one. + */ +goog.math.Long.prototype.div = function(other) { + if (other.isZero()) { + throw Error('division by zero'); + } else if (this.isZero()) { + return goog.math.Long.ZERO; + } + + if (this.equals(goog.math.Long.MIN_VALUE)) { + if (other.equals(goog.math.Long.ONE) || + other.equals(goog.math.Long.NEG_ONE)) { + return goog.math.Long.MIN_VALUE; // recall that -MIN_VALUE == MIN_VALUE + } else if (other.equals(goog.math.Long.MIN_VALUE)) { + return goog.math.Long.ONE; + } else { + // At this point, we have |other| >= 2, so |this/other| < |MIN_VALUE|. + var halfThis = this.shiftRight(1); + var approx = halfThis.div(other).shiftLeft(1); + if (approx.equals(goog.math.Long.ZERO)) { + return other.isNegative() ? goog.math.Long.ONE : goog.math.Long.NEG_ONE; + } else { + var rem = this.subtract(other.multiply(approx)); + var result = approx.add(rem.div(other)); + return result; + } + } + } else if (other.equals(goog.math.Long.MIN_VALUE)) { + return goog.math.Long.ZERO; + } + + if (this.isNegative()) { + if (other.isNegative()) { + return this.negate().div(other.negate()); + } else { + return this.negate().div(other).negate(); + } + } else if (other.isNegative()) { + return this.div(other.negate()).negate(); + } + + // Repeat the following until the remainder is less than other: find a + // floating-point that approximates remainder / other *from below*, add this + // into the result, and subtract it from the remainder. It is critical that + // the approximate value is less than or equal to the real value so that the + // remainder never becomes negative. + var res = goog.math.Long.ZERO; + var rem = this; + while (rem.greaterThanOrEqual(other)) { + // Approximate the result of division. This may be a little greater or + // smaller than the actual value. + var approx = Math.max(1, Math.floor(rem.toNumber() / other.toNumber())); + + // We will tweak the approximate result by changing it in the 48-th digit or + // the smallest non-fractional digit, whichever is larger. + var log2 = Math.ceil(Math.log(approx) / Math.LN2); + var delta = (log2 <= 48) ? 1 : Math.pow(2, log2 - 48); + + // Decrease the approximation until it is smaller than the remainder. Note + // that if it is too large, the product overflows and is negative. + var approxRes = goog.math.Long.fromNumber(approx); + var approxRem = approxRes.multiply(other); + while (approxRem.isNegative() || approxRem.greaterThan(rem)) { + approx -= delta; + approxRes = goog.math.Long.fromNumber(approx); + approxRem = approxRes.multiply(other); + } + + // We know the answer can't be zero... and actually, zero would cause + // infinite recursion since we would make no progress. + if (approxRes.isZero()) { + approxRes = goog.math.Long.ONE; + } + + res = res.add(approxRes); + rem = rem.subtract(approxRem); + } + return res; +}; + + +/** + * Returns this Long modulo the given one. + * @param {goog.math.Long} other Long by which to mod. + * @return {!goog.math.Long} This Long modulo the given one. + */ +goog.math.Long.prototype.modulo = function(other) { + return this.subtract(this.div(other).multiply(other)); +}; + + +/** @return {!goog.math.Long} The bitwise-NOT of this value. */ +goog.math.Long.prototype.not = function() { + return goog.math.Long.fromBits(~this.low_, ~this.high_); +}; + + +/** + * Returns the bitwise-AND of this Long and the given one. + * @param {goog.math.Long} other The Long with which to AND. + * @return {!goog.math.Long} The bitwise-AND of this and the other. + */ +goog.math.Long.prototype.and = function(other) { + return goog.math.Long.fromBits(this.low_ & other.low_, + this.high_ & other.high_); +}; + + +/** + * Returns the bitwise-OR of this Long and the given one. + * @param {goog.math.Long} other The Long with which to OR. + * @return {!goog.math.Long} The bitwise-OR of this and the other. + */ +goog.math.Long.prototype.or = function(other) { + return goog.math.Long.fromBits(this.low_ | other.low_, + this.high_ | other.high_); +}; + + +/** + * Returns the bitwise-XOR of this Long and the given one. + * @param {goog.math.Long} other The Long with which to XOR. + * @return {!goog.math.Long} The bitwise-XOR of this and the other. + */ +goog.math.Long.prototype.xor = function(other) { + return goog.math.Long.fromBits(this.low_ ^ other.low_, + this.high_ ^ other.high_); +}; + + +/** + * Returns this Long with bits shifted to the left by the given amount. + * @param {number} numBits The number of bits by which to shift. + * @return {!goog.math.Long} This shifted to the left by the given amount. + */ +goog.math.Long.prototype.shiftLeft = function(numBits) { + numBits &= 63; + if (numBits == 0) { + return this; + } else { + var low = this.low_; + if (numBits < 32) { + var high = this.high_; + return goog.math.Long.fromBits( + low << numBits, + (high << numBits) | (low >>> (32 - numBits))); + } else { + return goog.math.Long.fromBits(0, low << (numBits - 32)); + } + } +}; + + +/** + * Returns this Long with bits shifted to the right by the given amount. + * @param {number} numBits The number of bits by which to shift. + * @return {!goog.math.Long} This shifted to the right by the given amount. + */ +goog.math.Long.prototype.shiftRight = function(numBits) { + numBits &= 63; + if (numBits == 0) { + return this; + } else { + var high = this.high_; + if (numBits < 32) { + var low = this.low_; + return goog.math.Long.fromBits( + (low >>> numBits) | (high << (32 - numBits)), + high >> numBits); + } else { + return goog.math.Long.fromBits( + high >> (numBits - 32), + high >= 0 ? 0 : -1); + } + } +}; + + +/** + * Returns this Long with bits shifted to the right by the given amount, with + * the new top bits matching the current sign bit. + * @param {number} numBits The number of bits by which to shift. + * @return {!goog.math.Long} This shifted to the right by the given amount, with + * zeros placed into the new leading bits. + */ +goog.math.Long.prototype.shiftRightUnsigned = function(numBits) { + numBits &= 63; + if (numBits == 0) { + return this; + } else { + var high = this.high_; + if (numBits < 32) { + var low = this.low_; + return goog.math.Long.fromBits( + (low >>> numBits) | (high << (32 - numBits)), + high >>> numBits); + } else if (numBits == 32) { + return goog.math.Long.fromBits(high, 0); + } else { + return goog.math.Long.fromBits(high >>> (numBits - 32), 0); + } + } +}; |