| /* |
| * 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. |
| */ |
| |
| #ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_DECIMAL_H_ |
| #define THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_DECIMAL_H_ |
| |
| #include <cstdint> |
| |
| #include "third_party/blink/renderer/platform/wtf/allocator.h" |
| #include "third_party/blink/renderer/platform/wtf/assertions.h" |
| #include "third_party/blink/renderer/platform/wtf/text/wtf_string.h" |
| |
| namespace blink { |
| |
| namespace decimal_private { |
| class SpecialValueHandler; |
| } |
| |
| // This class represents decimal base floating point number. |
| // |
| // FIXME: Once all C++ compiler support decimal type, we should replace this |
| // class to compiler supported one. See below URI for current status of decimal |
| // type for C++: |
| // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1977.html |
| class WTF_EXPORT Decimal { |
| USING_FAST_MALLOC(Decimal); |
| |
| public: |
| enum Sign { |
| kPositive, |
| kNegative, |
| }; |
| |
| // You should not use EncodedData other than unit testing. |
| class EncodedData { |
| DISALLOW_NEW(); |
| // For accessing FormatClass. |
| friend class Decimal; |
| friend class decimal_private::SpecialValueHandler; |
| |
| public: |
| EncodedData(Sign, int exponent, uint64_t coefficient); |
| |
| bool operator==(const EncodedData&) const; |
| bool operator!=(const EncodedData& another) const { |
| return !operator==(another); |
| } |
| |
| uint64_t Coefficient() const { return coefficient_; } |
| int CountDigits() const; |
| int Exponent() const { return exponent_; } |
| bool IsFinite() const { return !IsSpecial(); } |
| bool IsInfinity() const { return format_class_ == kClassInfinity; } |
| bool IsNaN() const { return format_class_ == kClassNaN; } |
| bool IsSpecial() const { |
| return format_class_ == kClassInfinity || format_class_ == kClassNaN; |
| } |
| bool IsZero() const { return format_class_ == kClassZero; } |
| Sign GetSign() const { return sign_; } |
| void SetSign(Sign sign) { sign_ = sign; } |
| |
| private: |
| enum FormatClass { |
| kClassInfinity, |
| kClassNormal, |
| kClassNaN, |
| kClassZero, |
| }; |
| |
| EncodedData(Sign, FormatClass); |
| FormatClass GetFormatClass() const { return format_class_; } |
| |
| uint64_t coefficient_; |
| int16_t exponent_; |
| FormatClass format_class_; |
| Sign sign_; |
| }; |
| |
| Decimal(int32_t = 0); |
| Decimal(Sign, int exponent, uint64_t coefficient); |
| Decimal(const Decimal&); |
| |
| Decimal& operator=(const Decimal&); |
| Decimal& operator+=(const Decimal&); |
| Decimal& operator-=(const Decimal&); |
| Decimal& operator*=(const Decimal&); |
| Decimal& operator/=(const Decimal&); |
| |
| Decimal operator-() const; |
| |
| bool operator==(const Decimal&) const; |
| bool operator!=(const Decimal&) const; |
| bool operator<(const Decimal&) const; |
| bool operator<=(const Decimal&) const; |
| bool operator>(const Decimal&) const; |
| bool operator>=(const Decimal&) const; |
| |
| Decimal operator+(const Decimal&) const; |
| Decimal operator-(const Decimal&) const; |
| Decimal operator*(const Decimal&)const; |
| Decimal operator/(const Decimal&) const; |
| |
| int Exponent() const { |
| DCHECK(IsFinite()); |
| return data_.Exponent(); |
| } |
| |
| bool IsFinite() const { return data_.IsFinite(); } |
| bool IsInfinity() const { return data_.IsInfinity(); } |
| bool IsNaN() const { return data_.IsNaN(); } |
| bool IsNegative() const { return GetSign() == kNegative; } |
| bool IsPositive() const { return GetSign() == kPositive; } |
| bool IsSpecial() const { return data_.IsSpecial(); } |
| bool IsZero() const { return data_.IsZero(); } |
| |
| Decimal Abs() const; |
| Decimal Ceil() const; |
| Decimal Floor() const; |
| Decimal Remainder(const Decimal&) const; |
| Decimal Round() const; |
| |
| double ToDouble() const; |
| // Note: toString method supports infinity and nan but fromString not. |
| String ToString() const; |
| |
| static Decimal FromDouble(double); |
| // fromString supports following syntax EBNF: |
| // number ::= sign? digit+ ('.' digit*) (exponent-marker sign? digit+)? |
| // | sign? '.' digit+ (exponent-marker sign? digit+)? |
| // sign ::= '+' | '-' |
| // exponent-marker ::= 'e' | 'E' |
| // digit ::= '0' | '1' | ... | '9' |
| // Note: fromString doesn't support "infinity" and "nan". |
| static Decimal FromString(const String&); |
| static Decimal Infinity(Sign); |
| static Decimal Nan(); |
| static Decimal Zero(Sign); |
| |
| // You should not use below methods. We expose them for unit testing. |
| explicit Decimal(const EncodedData&); |
| const EncodedData& Value() const { return data_; } |
| |
| private: |
| struct AlignedOperands { |
| uint64_t lhs_coefficient; |
| uint64_t rhs_coefficient; |
| int exponent; |
| }; |
| |
| Decimal(double); |
| Decimal CompareTo(const Decimal&) const; |
| |
| static AlignedOperands AlignOperands(const Decimal& lhs, const Decimal& rhs); |
| static inline Sign InvertSign(Sign sign) { |
| return sign == kNegative ? kPositive : kNegative; |
| } |
| |
| Sign GetSign() const { return data_.GetSign(); } |
| |
| EncodedData data_; |
| }; |
| |
| WTF_EXPORT std::ostream& operator<<(std::ostream&, const Decimal&); |
| |
| } // namespace blink |
| |
| #endif // THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_DECIMAL_H_ |