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diff --git a/src/3rdparty/double-conversion/fixed-dtoa.cc b/src/3rdparty/double-conversion/fixed-dtoa.cc
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--- a/src/3rdparty/double-conversion/fixed-dtoa.cc
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-// Copyright 2010 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-// * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-// * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following
-// disclaimer in the documentation and/or other materials provided
-// with the distribution.
-// * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived
-// from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#include <cmath>
-
-#include <double-conversion/fixed-dtoa.h>
-#include <double-conversion/ieee.h>
-
-namespace double_conversion {
-
-// Represents a 128bit type. This class should be replaced by a native type on
-// platforms that support 128bit integers.
-class UInt128 {
- public:
- UInt128() : high_bits_(0), low_bits_(0) { }
- UInt128(uint64_t high, uint64_t low) : high_bits_(high), low_bits_(low) { }
-
- void Multiply(uint32_t multiplicand) {
- uint64_t accumulator;
-
- accumulator = (low_bits_ & kMask32) * multiplicand;
- uint32_t part = static_cast<uint32_t>(accumulator & kMask32);
- accumulator >>= 32;
- accumulator = accumulator + (low_bits_ >> 32) * multiplicand;
- low_bits_ = (accumulator << 32) + part;
- accumulator >>= 32;
- accumulator = accumulator + (high_bits_ & kMask32) * multiplicand;
- part = static_cast<uint32_t>(accumulator & kMask32);
- accumulator >>= 32;
- accumulator = accumulator + (high_bits_ >> 32) * multiplicand;
- high_bits_ = (accumulator << 32) + part;
- ASSERT((accumulator >> 32) == 0);
- }
-
- void Shift(int shift_amount) {
- ASSERT(-64 <= shift_amount && shift_amount <= 64);
- if (shift_amount == 0) {
- return;
- } else if (shift_amount == -64) {
- high_bits_ = low_bits_;
- low_bits_ = 0;
- } else if (shift_amount == 64) {
- low_bits_ = high_bits_;
- high_bits_ = 0;
- } else if (shift_amount <= 0) {
- high_bits_ <<= -shift_amount;
- high_bits_ += low_bits_ >> (64 + shift_amount);
- low_bits_ <<= -shift_amount;
- } else {
- low_bits_ >>= shift_amount;
- low_bits_ += high_bits_ << (64 - shift_amount);
- high_bits_ >>= shift_amount;
- }
- }
-
- // Modifies *this to *this MOD (2^power).
- // Returns *this DIV (2^power).
- int DivModPowerOf2(int power) {
- if (power >= 64) {
- int result = static_cast<int>(high_bits_ >> (power - 64));
- high_bits_ -= static_cast<uint64_t>(result) << (power - 64);
- return result;
- } else {
- uint64_t part_low = low_bits_ >> power;
- uint64_t part_high = high_bits_ << (64 - power);
- int result = static_cast<int>(part_low + part_high);
- high_bits_ = 0;
- low_bits_ -= part_low << power;
- return result;
- }
- }
-
- bool IsZero() const {
- return high_bits_ == 0 && low_bits_ == 0;
- }
-
- int BitAt(int position) const {
- if (position >= 64) {
- return static_cast<int>(high_bits_ >> (position - 64)) & 1;
- } else {
- return static_cast<int>(low_bits_ >> position) & 1;
- }
- }
-
- private:
- static const uint64_t kMask32 = 0xFFFFFFFF;
- // Value == (high_bits_ << 64) + low_bits_
- uint64_t high_bits_;
- uint64_t low_bits_;
-};
-
-
-static const int kDoubleSignificandSize = 53; // Includes the hidden bit.
-
-
-static void FillDigits32FixedLength(uint32_t number, int requested_length,
- Vector<char> buffer, int* length) {
- for (int i = requested_length - 1; i >= 0; --i) {
- buffer[(*length) + i] = '0' + number % 10;
- number /= 10;
- }
- *length += requested_length;
-}
-
-
-static void FillDigits32(uint32_t number, Vector<char> buffer, int* length) {
- int number_length = 0;
- // We fill the digits in reverse order and exchange them afterwards.
- while (number != 0) {
- int digit = number % 10;
- number /= 10;
- buffer[(*length) + number_length] = static_cast<char>('0' + digit);
- number_length++;
- }
- // Exchange the digits.
- int i = *length;
- int j = *length + number_length - 1;
- while (i < j) {
- char tmp = buffer[i];
- buffer[i] = buffer[j];
- buffer[j] = tmp;
- i++;
- j--;
- }
- *length += number_length;
-}
-
-
-static void FillDigits64FixedLength(uint64_t number,
- Vector<char> buffer, int* length) {
- const uint32_t kTen7 = 10000000;
- // For efficiency cut the number into 3 uint32_t parts, and print those.
- uint32_t part2 = static_cast<uint32_t>(number % kTen7);
- number /= kTen7;
- uint32_t part1 = static_cast<uint32_t>(number % kTen7);
- uint32_t part0 = static_cast<uint32_t>(number / kTen7);
-
- FillDigits32FixedLength(part0, 3, buffer, length);
- FillDigits32FixedLength(part1, 7, buffer, length);
- FillDigits32FixedLength(part2, 7, buffer, length);
-}
-
-
-static void FillDigits64(uint64_t number, Vector<char> buffer, int* length) {
- const uint32_t kTen7 = 10000000;
- // For efficiency cut the number into 3 uint32_t parts, and print those.
- uint32_t part2 = static_cast<uint32_t>(number % kTen7);
- number /= kTen7;
- uint32_t part1 = static_cast<uint32_t>(number % kTen7);
- uint32_t part0 = static_cast<uint32_t>(number / kTen7);
-
- if (part0 != 0) {
- FillDigits32(part0, buffer, length);
- FillDigits32FixedLength(part1, 7, buffer, length);
- FillDigits32FixedLength(part2, 7, buffer, length);
- } else if (part1 != 0) {
- FillDigits32(part1, buffer, length);
- FillDigits32FixedLength(part2, 7, buffer, length);
- } else {
- FillDigits32(part2, buffer, length);
- }
-}
-
-
-static void RoundUp(Vector<char> buffer, int* length, int* decimal_point) {
- // An empty buffer represents 0.
- if (*length == 0) {
- buffer[0] = '1';
- *decimal_point = 1;
- *length = 1;
- return;
- }
- // Round the last digit until we either have a digit that was not '9' or until
- // we reached the first digit.
- buffer[(*length) - 1]++;
- for (int i = (*length) - 1; i > 0; --i) {
- if (buffer[i] != '0' + 10) {
- return;
- }
- buffer[i] = '0';
- buffer[i - 1]++;
- }
- // If the first digit is now '0' + 10, we would need to set it to '0' and add
- // a '1' in front. However we reach the first digit only if all following
- // digits had been '9' before rounding up. Now all trailing digits are '0' and
- // we simply switch the first digit to '1' and update the decimal-point
- // (indicating that the point is now one digit to the right).
- if (buffer[0] == '0' + 10) {
- buffer[0] = '1';
- (*decimal_point)++;
- }
-}
-
-
-// The given fractionals number represents a fixed-point number with binary
-// point at bit (-exponent).
-// Preconditions:
-// -128 <= exponent <= 0.
-// 0 <= fractionals * 2^exponent < 1
-// The buffer holds the result.
-// The function will round its result. During the rounding-process digits not
-// generated by this function might be updated, and the decimal-point variable
-// might be updated. If this function generates the digits 99 and the buffer
-// already contained "199" (thus yielding a buffer of "19999") then a
-// rounding-up will change the contents of the buffer to "20000".
-static void FillFractionals(uint64_t fractionals, int exponent,
- int fractional_count, Vector<char> buffer,
- int* length, int* decimal_point) {
- ASSERT(-128 <= exponent && exponent <= 0);
- // 'fractionals' is a fixed-point number, with binary point at bit
- // (-exponent). Inside the function the non-converted remainder of fractionals
- // is a fixed-point number, with binary point at bit 'point'.
- if (-exponent <= 64) {
- // One 64 bit number is sufficient.
- ASSERT(fractionals >> 56 == 0);
- int point = -exponent;
- for (int i = 0; i < fractional_count; ++i) {
- if (fractionals == 0) break;
- // Instead of multiplying by 10 we multiply by 5 and adjust the point
- // location. This way the fractionals variable will not overflow.
- // Invariant at the beginning of the loop: fractionals < 2^point.
- // Initially we have: point <= 64 and fractionals < 2^56
- // After each iteration the point is decremented by one.
- // Note that 5^3 = 125 < 128 = 2^7.
- // Therefore three iterations of this loop will not overflow fractionals
- // (even without the subtraction at the end of the loop body). At this
- // time point will satisfy point <= 61 and therefore fractionals < 2^point
- // and any further multiplication of fractionals by 5 will not overflow.
- fractionals *= 5;
- point--;
- int digit = static_cast<int>(fractionals >> point);
- ASSERT(digit <= 9);
- buffer[*length] = static_cast<char>('0' + digit);
- (*length)++;
- fractionals -= static_cast<uint64_t>(digit) << point;
- }
- // If the first bit after the point is set we have to round up.
- ASSERT(fractionals == 0 || point - 1 >= 0);
- if ((fractionals != 0) && ((fractionals >> (point - 1)) & 1) == 1) {
- RoundUp(buffer, length, decimal_point);
- }
- } else { // We need 128 bits.
- ASSERT(64 < -exponent && -exponent <= 128);
- UInt128 fractionals128 = UInt128(fractionals, 0);
- fractionals128.Shift(-exponent - 64);
- int point = 128;
- for (int i = 0; i < fractional_count; ++i) {
- if (fractionals128.IsZero()) break;
- // As before: instead of multiplying by 10 we multiply by 5 and adjust the
- // point location.
- // This multiplication will not overflow for the same reasons as before.
- fractionals128.Multiply(5);
- point--;
- int digit = fractionals128.DivModPowerOf2(point);
- ASSERT(digit <= 9);
- buffer[*length] = static_cast<char>('0' + digit);
- (*length)++;
- }
- if (fractionals128.BitAt(point - 1) == 1) {
- RoundUp(buffer, length, decimal_point);
- }
- }
-}
-
-
-// Removes leading and trailing zeros.
-// If leading zeros are removed then the decimal point position is adjusted.
-static void TrimZeros(Vector<char> buffer, int* length, int* decimal_point) {
- while (*length > 0 && buffer[(*length) - 1] == '0') {
- (*length)--;
- }
- int first_non_zero = 0;
- while (first_non_zero < *length && buffer[first_non_zero] == '0') {
- first_non_zero++;
- }
- if (first_non_zero != 0) {
- for (int i = first_non_zero; i < *length; ++i) {
- buffer[i - first_non_zero] = buffer[i];
- }
- *length -= first_non_zero;
- *decimal_point -= first_non_zero;
- }
-}
-
-
-bool FastFixedDtoa(double v,
- int fractional_count,
- Vector<char> buffer,
- int* length,
- int* decimal_point) {
- const uint32_t kMaxUInt32 = 0xFFFFFFFF;
- uint64_t significand = Double(v).Significand();
- int exponent = Double(v).Exponent();
- // v = significand * 2^exponent (with significand a 53bit integer).
- // If the exponent is larger than 20 (i.e. we may have a 73bit number) then we
- // don't know how to compute the representation. 2^73 ~= 9.5*10^21.
- // If necessary this limit could probably be increased, but we don't need
- // more.
- if (exponent > 20) return false;
- if (fractional_count > 20) return false;
- *length = 0;
- // At most kDoubleSignificandSize bits of the significand are non-zero.
- // Given a 64 bit integer we have 11 0s followed by 53 potentially non-zero
- // bits: 0..11*..0xxx..53*..xx
- if (exponent + kDoubleSignificandSize > 64) {
- // The exponent must be > 11.
- //
- // We know that v = significand * 2^exponent.
- // And the exponent > 11.
- // We simplify the task by dividing v by 10^17.
- // The quotient delivers the first digits, and the remainder fits into a 64
- // bit number.
- // Dividing by 10^17 is equivalent to dividing by 5^17*2^17.
- const uint64_t kFive17 = UINT64_2PART_C(0xB1, A2BC2EC5); // 5^17
- uint64_t divisor = kFive17;
- int divisor_power = 17;
- uint64_t dividend = significand;
- uint32_t quotient;
- uint64_t remainder;
- // Let v = f * 2^e with f == significand and e == exponent.
- // Then need q (quotient) and r (remainder) as follows:
- // v = q * 10^17 + r
- // f * 2^e = q * 10^17 + r
- // f * 2^e = q * 5^17 * 2^17 + r
- // If e > 17 then
- // f * 2^(e-17) = q * 5^17 + r/2^17
- // else
- // f = q * 5^17 * 2^(17-e) + r/2^e
- if (exponent > divisor_power) {
- // We only allow exponents of up to 20 and therefore (17 - e) <= 3
- dividend <<= exponent - divisor_power;
- quotient = static_cast<uint32_t>(dividend / divisor);
- remainder = (dividend % divisor) << divisor_power;
- } else {
- divisor <<= divisor_power - exponent;
- quotient = static_cast<uint32_t>(dividend / divisor);
- remainder = (dividend % divisor) << exponent;
- }
- FillDigits32(quotient, buffer, length);
- FillDigits64FixedLength(remainder, buffer, length);
- *decimal_point = *length;
- } else if (exponent >= 0) {
- // 0 <= exponent <= 11
- significand <<= exponent;
- FillDigits64(significand, buffer, length);
- *decimal_point = *length;
- } else if (exponent > -kDoubleSignificandSize) {
- // We have to cut the number.
- uint64_t integrals = significand >> -exponent;
- uint64_t fractionals = significand - (integrals << -exponent);
- if (integrals > kMaxUInt32) {
- FillDigits64(integrals, buffer, length);
- } else {
- FillDigits32(static_cast<uint32_t>(integrals), buffer, length);
- }
- *decimal_point = *length;
- FillFractionals(fractionals, exponent, fractional_count,
- buffer, length, decimal_point);
- } else if (exponent < -128) {
- // This configuration (with at most 20 digits) means that all digits must be
- // 0.
- ASSERT(fractional_count <= 20);
- buffer[0] = '\0';
- *length = 0;
- *decimal_point = -fractional_count;
- } else {
- *decimal_point = 0;
- FillFractionals(significand, exponent, fractional_count,
- buffer, length, decimal_point);
- }
- TrimZeros(buffer, length, decimal_point);
- buffer[*length] = '\0';
- if ((*length) == 0) {
- // The string is empty and the decimal_point thus has no importance. Mimick
- // Gay's dtoa and and set it to -fractional_count.
- *decimal_point = -fractional_count;
- }
- return true;
-}
-
-} // namespace double_conversion
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