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diff --git a/mfbt/decimal/Decimal.cpp b/mfbt/decimal/Decimal.cpp
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+++ b/mfbt/decimal/Decimal.cpp
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+/*
+ * Copyright (C) 2012 Google Inc. 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 "Decimal.h"
+#include "moz-decimal-utils.h"
+
+using namespace moz_decimal_utils;
+
+#include <algorithm>
+#include <float.h>
+
+namespace blink {
+
+namespace DecimalPrivate {
+
+static int const ExponentMax = 1023;
+static int const ExponentMin = -1023;
+static int const Precision = 18;
+
+static const uint64_t MaxCoefficient = UINT64_C(0xDE0B6B3A763FFFF); // 999999999999999999 == 18 9's
+
+// This class handles Decimal special values.
+class SpecialValueHandler {
+ STACK_ALLOCATED();
+ WTF_MAKE_NONCOPYABLE(SpecialValueHandler);
+public:
+ enum HandleResult {
+ BothFinite,
+ BothInfinity,
+ EitherNaN,
+ LHSIsInfinity,
+ RHSIsInfinity,
+ };
+
+ SpecialValueHandler(const Decimal& lhs, const Decimal& rhs);
+ HandleResult handle();
+ Decimal value() const;
+
+private:
+ enum Result {
+ ResultIsLHS,
+ ResultIsRHS,
+ ResultIsUnknown,
+ };
+
+ const Decimal& m_lhs;
+ const Decimal& m_rhs;
+ Result m_result;
+};
+
+SpecialValueHandler::SpecialValueHandler(const Decimal& lhs, const Decimal& rhs)
+ : m_lhs(lhs), m_rhs(rhs), m_result(ResultIsUnknown)
+{
+}
+
+SpecialValueHandler::HandleResult SpecialValueHandler::handle()
+{
+ if (m_lhs.isFinite() && m_rhs.isFinite())
+ return BothFinite;
+
+ const Decimal::EncodedData::FormatClass lhsClass = m_lhs.value().formatClass();
+ const Decimal::EncodedData::FormatClass rhsClass = m_rhs.value().formatClass();
+ if (lhsClass == Decimal::EncodedData::ClassNaN) {
+ m_result = ResultIsLHS;
+ return EitherNaN;
+ }
+
+ if (rhsClass == Decimal::EncodedData::ClassNaN) {
+ m_result = ResultIsRHS;
+ return EitherNaN;
+ }
+
+ if (lhsClass == Decimal::EncodedData::ClassInfinity)
+ return rhsClass == Decimal::EncodedData::ClassInfinity ? BothInfinity : LHSIsInfinity;
+
+ if (rhsClass == Decimal::EncodedData::ClassInfinity)
+ return RHSIsInfinity;
+
+ ASSERT_NOT_REACHED();
+ return BothFinite;
+}
+
+Decimal SpecialValueHandler::value() const
+{
+ switch (m_result) {
+ case ResultIsLHS:
+ return m_lhs;
+ case ResultIsRHS:
+ return m_rhs;
+ case ResultIsUnknown:
+ default:
+ ASSERT_NOT_REACHED();
+ return m_lhs;
+ }
+}
+
+// This class is used for 128 bit unsigned integer arithmetic.
+class UInt128 {
+public:
+ UInt128(uint64_t low, uint64_t high)
+ : m_high(high), m_low(low)
+ {
+ }
+
+ UInt128& operator/=(uint32_t);
+
+ uint64_t high() const { return m_high; }
+ uint64_t low() const { return m_low; }
+
+ static UInt128 multiply(uint64_t u, uint64_t v) { return UInt128(u * v, multiplyHigh(u, v)); }
+
+private:
+ static uint32_t highUInt32(uint64_t x) { return static_cast<uint32_t>(x >> 32); }
+ static uint32_t lowUInt32(uint64_t x) { return static_cast<uint32_t>(x & ((static_cast<uint64_t>(1) << 32) - 1)); }
+ static uint64_t makeUInt64(uint32_t low, uint32_t high) { return low | (static_cast<uint64_t>(high) << 32); }
+
+ static uint64_t multiplyHigh(uint64_t, uint64_t);
+
+ uint64_t m_high;
+ uint64_t m_low;
+};
+
+UInt128& UInt128::operator/=(const uint32_t divisor)
+{
+ ASSERT(divisor);
+
+ if (!m_high) {
+ m_low /= divisor;
+ return *this;
+ }
+
+ uint32_t dividend[4];
+ dividend[0] = lowUInt32(m_low);
+ dividend[1] = highUInt32(m_low);
+ dividend[2] = lowUInt32(m_high);
+ dividend[3] = highUInt32(m_high);
+
+ uint32_t quotient[4];
+ uint32_t remainder = 0;
+ for (int i = 3; i >= 0; --i) {
+ const uint64_t work = makeUInt64(dividend[i], remainder);
+ remainder = static_cast<uint32_t>(work % divisor);
+ quotient[i] = static_cast<uint32_t>(work / divisor);
+ }
+ m_low = makeUInt64(quotient[0], quotient[1]);
+ m_high = makeUInt64(quotient[2], quotient[3]);
+ return *this;
+}
+
+// Returns high 64bit of 128bit product.
+uint64_t UInt128::multiplyHigh(uint64_t u, uint64_t v)
+{
+ const uint64_t uLow = lowUInt32(u);
+ const uint64_t uHigh = highUInt32(u);
+ const uint64_t vLow = lowUInt32(v);
+ const uint64_t vHigh = highUInt32(v);
+ const uint64_t partialProduct = uHigh * vLow + highUInt32(uLow * vLow);
+ return uHigh * vHigh + highUInt32(partialProduct) + highUInt32(uLow * vHigh + lowUInt32(partialProduct));
+}
+
+static int countDigits(uint64_t x)
+{
+ int numberOfDigits = 0;
+ for (uint64_t powerOfTen = 1; x >= powerOfTen; powerOfTen *= 10) {
+ ++numberOfDigits;
+ if (powerOfTen >= std::numeric_limits<uint64_t>::max() / 10)
+ break;
+ }
+ return numberOfDigits;
+}
+
+static uint64_t scaleDown(uint64_t x, int n)
+{
+ ASSERT(n >= 0);
+ while (n > 0 && x) {
+ x /= 10;
+ --n;
+ }
+ return x;
+}
+
+static uint64_t scaleUp(uint64_t x, int n)
+{
+ ASSERT(n >= 0);
+ ASSERT(n <= Precision);
+
+ uint64_t y = 1;
+ uint64_t z = 10;
+ for (;;) {
+ if (n & 1)
+ y = y * z;
+
+ n >>= 1;
+ if (!n)
+ return x * y;
+
+ z = z * z;
+ }
+}
+
+} // namespace DecimalPrivate
+
+using namespace DecimalPrivate;
+
+Decimal::EncodedData::EncodedData(Sign sign, FormatClass formatClass)
+ : m_coefficient(0)
+ , m_exponent(0)
+ , m_formatClass(formatClass)
+ , m_sign(sign)
+{
+}
+
+Decimal::EncodedData::EncodedData(Sign sign, int exponent, uint64_t coefficient)
+ : m_formatClass(coefficient ? ClassNormal : ClassZero)
+ , m_sign(sign)
+{
+ if (exponent >= ExponentMin && exponent <= ExponentMax) {
+ while (coefficient > MaxCoefficient) {
+ coefficient /= 10;
+ ++exponent;
+ }
+ }
+
+ if (exponent > ExponentMax) {
+ m_coefficient = 0;
+ m_exponent = 0;
+ m_formatClass = ClassInfinity;
+ return;
+ }
+
+ if (exponent < ExponentMin) {
+ m_coefficient = 0;
+ m_exponent = 0;
+ m_formatClass = ClassZero;
+ return;
+ }
+
+ m_coefficient = coefficient;
+ m_exponent = static_cast<int16_t>(exponent);
+}
+
+bool Decimal::EncodedData::operator==(const EncodedData& another) const
+{
+ return m_sign == another.m_sign
+ && m_formatClass == another.m_formatClass
+ && m_exponent == another.m_exponent
+ && m_coefficient == another.m_coefficient;
+}
+
+Decimal::Decimal(int32_t i32)
+ : m_data(i32 < 0 ? Negative : Positive, 0, i32 < 0 ? static_cast<uint64_t>(-static_cast<int64_t>(i32)) : static_cast<uint64_t>(i32))
+{
+}
+
+Decimal::Decimal(Sign sign, int exponent, uint64_t coefficient)
+ : m_data(sign, coefficient ? exponent : 0, coefficient)
+{
+}
+
+Decimal::Decimal(const EncodedData& data)
+ : m_data(data)
+{
+}
+
+Decimal::Decimal(const Decimal& other)
+ : m_data(other.m_data)
+{
+}
+
+Decimal& Decimal::operator=(const Decimal& other)
+{
+ m_data = other.m_data;
+ return *this;
+}
+
+Decimal& Decimal::operator+=(const Decimal& other)
+{
+ m_data = (*this + other).m_data;
+ return *this;
+}
+
+Decimal& Decimal::operator-=(const Decimal& other)
+{
+ m_data = (*this - other).m_data;
+ return *this;
+}
+
+Decimal& Decimal::operator*=(const Decimal& other)
+{
+ m_data = (*this * other).m_data;
+ return *this;
+}
+
+Decimal& Decimal::operator/=(const Decimal& other)
+{
+ m_data = (*this / other).m_data;
+ return *this;
+}
+
+Decimal Decimal::operator-() const
+{
+ if (isNaN())
+ return *this;
+
+ Decimal result(*this);
+ result.m_data.setSign(invertSign(m_data.sign()));
+ return result;
+}
+
+Decimal Decimal::operator+(const Decimal& rhs) const
+{
+ const Decimal& lhs = *this;
+ const Sign lhsSign = lhs.sign();
+ const Sign rhsSign = rhs.sign();
+
+ SpecialValueHandler handler(lhs, rhs);
+ switch (handler.handle()) {
+ case SpecialValueHandler::BothFinite:
+ break;
+
+ case SpecialValueHandler::BothInfinity:
+ return lhsSign == rhsSign ? lhs : nan();
+
+ case SpecialValueHandler::EitherNaN:
+ return handler.value();
+
+ case SpecialValueHandler::LHSIsInfinity:
+ return lhs;
+
+ case SpecialValueHandler::RHSIsInfinity:
+ return rhs;
+ }
+
+ const AlignedOperands alignedOperands = alignOperands(lhs, rhs);
+
+ const uint64_t result = lhsSign == rhsSign
+ ? alignedOperands.lhsCoefficient + alignedOperands.rhsCoefficient
+ : alignedOperands.lhsCoefficient - alignedOperands.rhsCoefficient;
+
+ if (lhsSign == Negative && rhsSign == Positive && !result)
+ return Decimal(Positive, alignedOperands.exponent, 0);
+
+ return static_cast<int64_t>(result) >= 0
+ ? Decimal(lhsSign, alignedOperands.exponent, result)
+ : Decimal(invertSign(lhsSign), alignedOperands.exponent, -static_cast<int64_t>(result));
+}
+
+Decimal Decimal::operator-(const Decimal& rhs) const
+{
+ const Decimal& lhs = *this;
+ const Sign lhsSign = lhs.sign();
+ const Sign rhsSign = rhs.sign();
+
+ SpecialValueHandler handler(lhs, rhs);
+ switch (handler.handle()) {
+ case SpecialValueHandler::BothFinite:
+ break;
+
+ case SpecialValueHandler::BothInfinity:
+ return lhsSign == rhsSign ? nan() : lhs;
+
+ case SpecialValueHandler::EitherNaN:
+ return handler.value();
+
+ case SpecialValueHandler::LHSIsInfinity:
+ return lhs;
+
+ case SpecialValueHandler::RHSIsInfinity:
+ return infinity(invertSign(rhsSign));
+ }
+
+ const AlignedOperands alignedOperands = alignOperands(lhs, rhs);
+
+ const uint64_t result = lhsSign == rhsSign
+ ? alignedOperands.lhsCoefficient - alignedOperands.rhsCoefficient
+ : alignedOperands.lhsCoefficient + alignedOperands.rhsCoefficient;
+
+ if (lhsSign == Negative && rhsSign == Negative && !result)
+ return Decimal(Positive, alignedOperands.exponent, 0);
+
+ return static_cast<int64_t>(result) >= 0
+ ? Decimal(lhsSign, alignedOperands.exponent, result)
+ : Decimal(invertSign(lhsSign), alignedOperands.exponent, -static_cast<int64_t>(result));
+}
+
+Decimal Decimal::operator*(const Decimal& rhs) const
+{
+ const Decimal& lhs = *this;
+ const Sign lhsSign = lhs.sign();
+ const Sign rhsSign = rhs.sign();
+ const Sign resultSign = lhsSign == rhsSign ? Positive : Negative;
+
+ SpecialValueHandler handler(lhs, rhs);
+ switch (handler.handle()) {
+ case SpecialValueHandler::BothFinite: {
+ const uint64_t lhsCoefficient = lhs.m_data.coefficient();
+ const uint64_t rhsCoefficient = rhs.m_data.coefficient();
+ int resultExponent = lhs.exponent() + rhs.exponent();
+ UInt128 work(UInt128::multiply(lhsCoefficient, rhsCoefficient));
+ while (work.high()) {
+ work /= 10;
+ ++resultExponent;
+ }
+ return Decimal(resultSign, resultExponent, work.low());
+ }
+
+ case SpecialValueHandler::BothInfinity:
+ return infinity(resultSign);
+
+ case SpecialValueHandler::EitherNaN:
+ return handler.value();
+
+ case SpecialValueHandler::LHSIsInfinity:
+ return rhs.isZero() ? nan() : infinity(resultSign);
+
+ case SpecialValueHandler::RHSIsInfinity:
+ return lhs.isZero() ? nan() : infinity(resultSign);
+ }
+
+ ASSERT_NOT_REACHED();
+ return nan();
+}
+
+Decimal Decimal::operator/(const Decimal& rhs) const
+{
+ const Decimal& lhs = *this;
+ const Sign lhsSign = lhs.sign();
+ const Sign rhsSign = rhs.sign();
+ const Sign resultSign = lhsSign == rhsSign ? Positive : Negative;
+
+ SpecialValueHandler handler(lhs, rhs);
+ switch (handler.handle()) {
+ case SpecialValueHandler::BothFinite:
+ break;
+
+ case SpecialValueHandler::BothInfinity:
+ return nan();
+
+ case SpecialValueHandler::EitherNaN:
+ return handler.value();
+
+ case SpecialValueHandler::LHSIsInfinity:
+ return infinity(resultSign);
+
+ case SpecialValueHandler::RHSIsInfinity:
+ return zero(resultSign);
+ }
+
+ ASSERT(lhs.isFinite());
+ ASSERT(rhs.isFinite());
+
+ if (rhs.isZero())
+ return lhs.isZero() ? nan() : infinity(resultSign);
+
+ int resultExponent = lhs.exponent() - rhs.exponent();
+
+ if (lhs.isZero())
+ return Decimal(resultSign, resultExponent, 0);
+
+ uint64_t remainder = lhs.m_data.coefficient();
+ const uint64_t divisor = rhs.m_data.coefficient();
+ uint64_t result = 0;
+ for (;;) {
+ while (remainder < divisor && result < MaxCoefficient / 10) {
+ remainder *= 10;
+ result *= 10;
+ --resultExponent;
+ }
+ if (remainder < divisor)
+ break;
+ uint64_t quotient = remainder / divisor;
+ if (result > MaxCoefficient - quotient)
+ break;
+ result += quotient;
+ remainder %= divisor;
+ if (!remainder)
+ break;
+ }
+
+ if (remainder > divisor / 2)
+ ++result;
+
+ return Decimal(resultSign, resultExponent, result);
+}
+
+bool Decimal::operator==(const Decimal& rhs) const
+{
+ if (isNaN() || rhs.isNaN())
+ return false;
+ return m_data == rhs.m_data || compareTo(rhs).isZero();
+}
+
+bool Decimal::operator!=(const Decimal& rhs) const
+{
+ if (isNaN() || rhs.isNaN())
+ return true;
+ if (m_data == rhs.m_data)
+ return false;
+ const Decimal result = compareTo(rhs);
+ if (result.isNaN())
+ return false;
+ return !result.isZero();
+}
+
+bool Decimal::operator<(const Decimal& rhs) const
+{
+ const Decimal result = compareTo(rhs);
+ if (result.isNaN())
+ return false;
+ return !result.isZero() && result.isNegative();
+}
+
+bool Decimal::operator<=(const Decimal& rhs) const
+{
+ if (isNaN() || rhs.isNaN())
+ return false;
+ if (m_data == rhs.m_data)
+ return true;
+ const Decimal result = compareTo(rhs);
+ if (result.isNaN())
+ return false;
+ return result.isZero() || result.isNegative();
+}
+
+bool Decimal::operator>(const Decimal& rhs) const
+{
+ const Decimal result = compareTo(rhs);
+ if (result.isNaN())
+ return false;
+ return !result.isZero() && result.isPositive();
+}
+
+bool Decimal::operator>=(const Decimal& rhs) const
+{
+ if (isNaN() || rhs.isNaN())
+ return false;
+ if (m_data == rhs.m_data)
+ return true;
+ const Decimal result = compareTo(rhs);
+ if (result.isNaN())
+ return false;
+ return result.isZero() || !result.isNegative();
+}
+
+Decimal Decimal::abs() const
+{
+ Decimal result(*this);
+ result.m_data.setSign(Positive);
+ return result;
+}
+
+Decimal::AlignedOperands Decimal::alignOperands(const Decimal& lhs, const Decimal& rhs)
+{
+ ASSERT(lhs.isFinite());
+ ASSERT(rhs.isFinite());
+
+ const int lhsExponent = lhs.exponent();
+ const int rhsExponent = rhs.exponent();
+ int exponent = std::min(lhsExponent, rhsExponent);
+ uint64_t lhsCoefficient = lhs.m_data.coefficient();
+ uint64_t rhsCoefficient = rhs.m_data.coefficient();
+
+ if (lhsExponent > rhsExponent) {
+ const int numberOfLHSDigits = countDigits(lhsCoefficient);
+ if (numberOfLHSDigits) {
+ const int lhsShiftAmount = lhsExponent - rhsExponent;
+ const int overflow = numberOfLHSDigits + lhsShiftAmount - Precision;
+ if (overflow <= 0) {
+ lhsCoefficient = scaleUp(lhsCoefficient, lhsShiftAmount);
+ } else {
+ lhsCoefficient = scaleUp(lhsCoefficient, lhsShiftAmount - overflow);
+ rhsCoefficient = scaleDown(rhsCoefficient, overflow);
+ exponent += overflow;
+ }
+ }
+
+ } else if (lhsExponent < rhsExponent) {
+ const int numberOfRHSDigits = countDigits(rhsCoefficient);
+ if (numberOfRHSDigits) {
+ const int rhsShiftAmount = rhsExponent - lhsExponent;
+ const int overflow = numberOfRHSDigits + rhsShiftAmount - Precision;
+ if (overflow <= 0) {
+ rhsCoefficient = scaleUp(rhsCoefficient, rhsShiftAmount);
+ } else {
+ rhsCoefficient = scaleUp(rhsCoefficient, rhsShiftAmount - overflow);
+ lhsCoefficient = scaleDown(lhsCoefficient, overflow);
+ exponent += overflow;
+ }
+ }
+ }
+
+ AlignedOperands alignedOperands;
+ alignedOperands.exponent = exponent;
+ alignedOperands.lhsCoefficient = lhsCoefficient;
+ alignedOperands.rhsCoefficient = rhsCoefficient;
+ return alignedOperands;
+}
+
+static bool isMultiplePowersOfTen(uint64_t coefficient, int n)
+{
+ return !coefficient || !(coefficient % scaleUp(1, n));
+}
+
+// Round toward positive infinity.
+Decimal Decimal::ceil() const
+{
+ if (isSpecial())
+ return *this;
+
+ if (exponent() >= 0)
+ return *this;
+
+ uint64_t result = m_data.coefficient();
+ const int numberOfDigits = countDigits(result);
+ const int numberOfDropDigits = -exponent();
+ if (numberOfDigits <= numberOfDropDigits)
+ return isPositive() ? Decimal(1) : zero(Positive);
+
+ result = scaleDown(result, numberOfDropDigits);
+ if (isPositive() && !isMultiplePowersOfTen(m_data.coefficient(), numberOfDropDigits))
+ ++result;
+ return Decimal(sign(), 0, result);
+}
+
+Decimal Decimal::compareTo(const Decimal& rhs) const
+{
+ const Decimal result(*this - rhs);
+ switch (result.m_data.formatClass()) {
+ case EncodedData::ClassInfinity:
+ return result.isNegative() ? Decimal(-1) : Decimal(1);
+
+ case EncodedData::ClassNaN:
+ case EncodedData::ClassNormal:
+ return result;
+
+ case EncodedData::ClassZero:
+ return zero(Positive);
+
+ default:
+ ASSERT_NOT_REACHED();
+ return nan();
+ }
+}
+
+// Round toward negative infinity.
+Decimal Decimal::floor() const
+{
+ if (isSpecial())
+ return *this;
+
+ if (exponent() >= 0)
+ return *this;
+
+ uint64_t result = m_data.coefficient();
+ const int numberOfDigits = countDigits(result);
+ const int numberOfDropDigits = -exponent();
+ if (numberOfDigits < numberOfDropDigits)
+ return isPositive() ? zero(Positive) : Decimal(-1);
+
+ result = scaleDown(result, numberOfDropDigits);
+ if (isNegative() && !isMultiplePowersOfTen(m_data.coefficient(), numberOfDropDigits))
+ ++result;
+ return Decimal(sign(), 0, result);
+}
+
+Decimal Decimal::fromDouble(double doubleValue)
+{
+ if (std::isfinite(doubleValue))
+ return fromString(mozToString(doubleValue));
+
+ if (std::isinf(doubleValue))
+ return infinity(doubleValue < 0 ? Negative : Positive);
+
+ return nan();
+}
+
+Decimal Decimal::fromString(const String& str)
+{
+ int exponent = 0;
+ Sign exponentSign = Positive;
+ int numberOfDigits = 0;
+ int numberOfDigitsAfterDot = 0;
+ int numberOfExtraDigits = 0;
+ Sign sign = Positive;
+
+ enum {
+ StateDigit,
+ StateDot,
+ StateDotDigit,
+ StateE,
+ StateEDigit,
+ StateESign,
+ StateSign,
+ StateStart,
+ StateZero,
+ } state = StateStart;
+
+#define HandleCharAndBreak(expected, nextState) \
+ if (ch == expected) { \
+ state = nextState; \
+ break; \
+ }
+
+#define HandleTwoCharsAndBreak(expected1, expected2, nextState) \
+ if (ch == expected1 || ch == expected2) { \
+ state = nextState; \
+ break; \
+ }
+
+ uint64_t accumulator = 0;
+ for (unsigned index = 0; index < str.length(); ++index) {
+ const int ch = str[index];
+ switch (state) {
+ case StateDigit:
+ if (ch >= '0' && ch <= '9') {
+ if (numberOfDigits < Precision) {
+ ++numberOfDigits;
+ accumulator *= 10;
+ accumulator += ch - '0';
+ } else {
+ ++numberOfExtraDigits;
+ }
+ break;
+ }
+
+ HandleCharAndBreak('.', StateDot);
+ HandleTwoCharsAndBreak('E', 'e', StateE);
+ return nan();
+
+ case StateDot:
+ case StateDotDigit:
+ if (ch >= '0' && ch <= '9') {
+ if (numberOfDigits < Precision) {
+ ++numberOfDigits;
+ ++numberOfDigitsAfterDot;
+ accumulator *= 10;
+ accumulator += ch - '0';
+ }
+ state = StateDotDigit;
+ break;
+ }
+
+ HandleTwoCharsAndBreak('E', 'e', StateE);
+ return nan();
+
+ case StateE:
+ if (ch == '+') {
+ exponentSign = Positive;
+ state = StateESign;
+ break;
+ }
+
+ if (ch == '-') {
+ exponentSign = Negative;
+ state = StateESign;
+ break;
+ }
+
+ if (ch >= '0' && ch <= '9') {
+ exponent = ch - '0';
+ state = StateEDigit;
+ break;
+ }
+
+ return nan();
+
+ case StateEDigit:
+ if (ch >= '0' && ch <= '9') {
+ exponent *= 10;
+ exponent += ch - '0';
+ if (exponent > ExponentMax + Precision) {
+ if (accumulator)
+ return exponentSign == Negative ? zero(Positive) : infinity(sign);
+ return zero(sign);
+ }
+ state = StateEDigit;
+ break;
+ }
+
+ return nan();
+
+ case StateESign:
+ if (ch >= '0' && ch <= '9') {
+ exponent = ch - '0';
+ state = StateEDigit;
+ break;
+ }
+
+ return nan();
+
+ case StateSign:
+ if (ch >= '1' && ch <= '9') {
+ accumulator = ch - '0';
+ numberOfDigits = 1;
+ state = StateDigit;
+ break;
+ }
+
+ HandleCharAndBreak('0', StateZero);
+ return nan();
+
+ case StateStart:
+ if (ch >= '1' && ch <= '9') {
+ accumulator = ch - '0';
+ numberOfDigits = 1;
+ state = StateDigit;
+ break;
+ }
+
+ if (ch == '-') {
+ sign = Negative;
+ state = StateSign;
+ break;
+ }
+
+ if (ch == '+') {
+ sign = Positive;
+ state = StateSign;
+ break;
+ }
+
+ HandleCharAndBreak('0', StateZero);
+ HandleCharAndBreak('.', StateDot);
+ return nan();
+
+ case StateZero:
+ if (ch == '0')
+ break;
+
+ if (ch >= '1' && ch <= '9') {
+ accumulator = ch - '0';
+ numberOfDigits = 1;
+ state = StateDigit;
+ break;
+ }
+
+ HandleCharAndBreak('.', StateDot);
+ HandleTwoCharsAndBreak('E', 'e', StateE);
+ return nan();
+
+ default:
+ ASSERT_NOT_REACHED();
+ return nan();
+ }
+ }
+
+ if (state == StateZero)
+ return zero(sign);
+
+ if (state == StateDigit || state == StateEDigit || state == StateDotDigit) {
+ int resultExponent = exponent * (exponentSign == Negative ? -1 : 1) - numberOfDigitsAfterDot + numberOfExtraDigits;
+ if (resultExponent < ExponentMin)
+ return zero(Positive);
+
+ const int overflow = resultExponent - ExponentMax + 1;
+ if (overflow > 0) {
+ if (overflow + numberOfDigits - numberOfDigitsAfterDot > Precision)
+ return infinity(sign);
+ accumulator = scaleUp(accumulator, overflow);
+ resultExponent -= overflow;
+ }
+
+ return Decimal(sign, resultExponent, accumulator);
+ }
+
+ return nan();
+}
+
+Decimal Decimal::infinity(const Sign sign)
+{
+ return Decimal(EncodedData(sign, EncodedData::ClassInfinity));
+}
+
+Decimal Decimal::nan()
+{
+ return Decimal(EncodedData(Positive, EncodedData::ClassNaN));
+}
+
+Decimal Decimal::remainder(const Decimal& rhs) const
+{
+ const Decimal quotient = *this / rhs;
+ return quotient.isSpecial() ? quotient : *this - (quotient.isNegative() ? quotient.ceil() : quotient.floor()) * rhs;
+}
+
+Decimal Decimal::round() const
+{
+ if (isSpecial())
+ return *this;
+
+ if (exponent() >= 0)
+ return *this;
+
+ uint64_t result = m_data.coefficient();
+ const int numberOfDigits = countDigits(result);
+ const int numberOfDropDigits = -exponent();
+ if (numberOfDigits < numberOfDropDigits)
+ return zero(Positive);
+
+ result = scaleDown(result, numberOfDropDigits - 1);
+ if (result % 10 >= 5)
+ result += 10;
+ result /= 10;
+ return Decimal(sign(), 0, result);
+}
+
+double Decimal::toDouble() const
+{
+ if (isFinite()) {
+ bool valid;
+ const double doubleValue = mozToDouble(toString(), &valid);
+ return valid ? doubleValue : std::numeric_limits<double>::quiet_NaN();
+ }
+
+ if (isInfinity())
+ return isNegative() ? -std::numeric_limits<double>::infinity() : std::numeric_limits<double>::infinity();
+
+ return std::numeric_limits<double>::quiet_NaN();
+}
+
+String Decimal::toString() const
+{
+ switch (m_data.formatClass()) {
+ case EncodedData::ClassInfinity:
+ return sign() ? "-Infinity" : "Infinity";
+
+ case EncodedData::ClassNaN:
+ return "NaN";
+
+ case EncodedData::ClassNormal:
+ case EncodedData::ClassZero:
+ break;
+
+ default:
+ ASSERT_NOT_REACHED();
+ return "";
+ }
+
+ StringBuilder builder;
+ if (sign())
+ builder.append('-');
+
+ int originalExponent = exponent();
+ uint64_t coefficient = m_data.coefficient();
+
+ if (originalExponent < 0) {
+ const int maxDigits = DBL_DIG;
+ uint64_t lastDigit = 0;
+ while (countDigits(coefficient) > maxDigits) {
+ lastDigit = coefficient % 10;
+ coefficient /= 10;
+ ++originalExponent;
+ }
+
+ if (lastDigit >= 5)
+ ++coefficient;
+
+ while (originalExponent < 0 && coefficient && !(coefficient % 10)) {
+ coefficient /= 10;
+ ++originalExponent;
+ }
+ }
+
+ const String digits = mozToString(coefficient);
+ int coefficientLength = static_cast<int>(digits.length());
+ const int adjustedExponent = originalExponent + coefficientLength - 1;
+ if (originalExponent <= 0 && adjustedExponent >= -6) {
+ if (!originalExponent) {
+ builder.append(digits);
+ return builder.toString();
+ }
+
+ if (adjustedExponent >= 0) {
+ for (int i = 0; i < coefficientLength; ++i) {
+ builder.append(digits[i]);
+ if (i == adjustedExponent)
+ builder.append('.');
+ }
+ return builder.toString();
+ }
+
+ builder.appendLiteral("0.");
+ for (int i = adjustedExponent + 1; i < 0; ++i)
+ builder.append('0');
+
+ builder.append(digits);
+
+ } else {
+ builder.append(digits[0]);
+ while (coefficientLength >= 2 && digits[coefficientLength - 1] == '0')
+ --coefficientLength;
+ if (coefficientLength >= 2) {
+ builder.append('.');
+ for (int i = 1; i < coefficientLength; ++i)
+ builder.append(digits[i]);
+ }
+
+ if (adjustedExponent) {
+ builder.append(adjustedExponent < 0 ? "e" : "e+");
+ builder.appendNumber(adjustedExponent);
+ }
+ }
+ return builder.toString();
+}
+
+bool Decimal::toString(char* strBuf, size_t bufLength) const
+{
+ ASSERT(bufLength > 0);
+ String str = toString();
+ size_t length = str.copy(strBuf, bufLength);
+ if (length < bufLength) {
+ strBuf[length] = '\0';
+ return true;
+ }
+ strBuf[bufLength - 1] = '\0';
+ return false;
+}
+
+Decimal Decimal::zero(Sign sign)
+{
+ return Decimal(EncodedData(sign, EncodedData::ClassZero));
+}
+
+} // namespace blink
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-10 16:26:27 +0000