diff options
Diffstat (limited to 'mozglue/misc/decimal/Decimal.h')
| -rw-r--r-- | mozglue/misc/decimal/Decimal.h | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/mozglue/misc/decimal/Decimal.h b/mozglue/misc/decimal/Decimal.h new file mode 100644 index 0000000000..10d0e2c7ce --- /dev/null +++ b/mozglue/misc/decimal/Decimal.h @@ -0,0 +1,221 @@ +/* + * 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. + */ + +/** + * Imported from: + * https://chromium.googlesource.com/chromium/src.git/+/master/third_party/WebKit/Source/platform/Decimal.h + * Check UPSTREAM-GIT-SHA for the commit ID of the last update from Blink core. + */ + +#ifndef Decimal_h +#define Decimal_h + +#include "mozilla/Assertions.h" +#include <stdint.h> +#include "mozilla/Types.h" + +#include <string> + +#ifndef ASSERT +#define DEFINED_ASSERT_FOR_DECIMAL_H 1 +#define ASSERT MOZ_ASSERT +#endif + +#define PLATFORM_EXPORT + +// To use USING_FAST_MALLOC we'd need: +// https://chromium.googlesource.com/chromium/src.git/+/master/third_party/WebKit/Source/wtf/Allocator.h +// Since we don't allocate Decimal objects, no need. +#define USING_FAST_MALLOC(type) \ + void ignore_this_dummy_method() = delete + +#define DISALLOW_NEW() \ + private: \ + void* operator new(size_t) = delete; \ + void* operator new(size_t, void*) = delete; \ + public: + +namespace blink { + +namespace DecimalPrivate { +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 PLATFORM_EXPORT Decimal { + USING_FAST_MALLOC(Decimal); +public: + enum Sign { + Positive, + Negative, + }; + + // You should not use EncodedData other than unit testing. + class EncodedData { + DISALLOW_NEW(); + // For accessing FormatClass. + friend class Decimal; + friend class DecimalPrivate::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 m_coefficient; } + int countDigits() const; + int exponent() const { return m_exponent; } + bool isFinite() const { return !isSpecial(); } + bool isInfinity() const { return m_formatClass == ClassInfinity; } + bool isNaN() const { return m_formatClass == ClassNaN; } + bool isSpecial() const { return m_formatClass == ClassInfinity || m_formatClass == ClassNaN; } + bool isZero() const { return m_formatClass == ClassZero; } + Sign sign() const { return m_sign; } + void setSign(Sign sign) { m_sign = sign; } + + private: + enum FormatClass { + ClassInfinity, + ClassNormal, + ClassNaN, + ClassZero, + }; + + EncodedData(Sign, FormatClass); + FormatClass formatClass() const { return m_formatClass; } + + uint64_t m_coefficient; + int16_t m_exponent; + FormatClass m_formatClass; + Sign m_sign; + }; + + MFBT_API explicit Decimal(int32_t = 0); + MFBT_API Decimal(Sign, int exponent, uint64_t coefficient); + MFBT_API Decimal(const Decimal&); + + MFBT_API Decimal& operator=(const Decimal&); + MFBT_API Decimal& operator+=(const Decimal&); + MFBT_API Decimal& operator-=(const Decimal&); + MFBT_API Decimal& operator*=(const Decimal&); + MFBT_API Decimal& operator/=(const Decimal&); + + MFBT_API Decimal operator-() const; + + MFBT_API bool operator==(const Decimal&) const; + MFBT_API bool operator!=(const Decimal&) const; + MFBT_API bool operator<(const Decimal&) const; + MFBT_API bool operator<=(const Decimal&) const; + MFBT_API bool operator>(const Decimal&) const; + MFBT_API bool operator>=(const Decimal&) const; + + MFBT_API Decimal operator+(const Decimal&) const; + MFBT_API Decimal operator-(const Decimal&) const; + MFBT_API Decimal operator*(const Decimal&) const; + MFBT_API Decimal operator/(const Decimal&) const; + + int exponent() const + { + ASSERT(isFinite()); + return m_data.exponent(); + } + + bool isFinite() const { return m_data.isFinite(); } + bool isInfinity() const { return m_data.isInfinity(); } + bool isNaN() const { return m_data.isNaN(); } + bool isNegative() const { return sign() == Negative; } + bool isPositive() const { return sign() == Positive; } + bool isSpecial() const { return m_data.isSpecial(); } + bool isZero() const { return m_data.isZero(); } + + MFBT_API Decimal abs() const; + MFBT_API Decimal ceil() const; + MFBT_API Decimal floor() const; + MFBT_API Decimal remainder(const Decimal&) const; + MFBT_API Decimal round() const; + + MFBT_API double toDouble() const; + // Note: toString method supports infinity and nan but fromString not. + MFBT_API std::string toString() const; + MFBT_API bool toString(char* strBuf, size_t bufLength) const; + + static MFBT_API 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 MFBT_API Decimal fromString(const std::string& aValue); + static MFBT_API Decimal infinity(Sign); + static MFBT_API Decimal nan(); + static MFBT_API Decimal zero(Sign); + + // You should not use below methods. We expose them for unit testing. + MFBT_API explicit Decimal(const EncodedData&); + const EncodedData& value() const { return m_data; } + +private: + struct AlignedOperands { + uint64_t lhsCoefficient; + uint64_t rhsCoefficient; + int exponent; + }; + + MFBT_API explicit Decimal(double); + MFBT_API Decimal compareTo(const Decimal&) const; + + static MFBT_API AlignedOperands alignOperands(const Decimal& lhs, const Decimal& rhs); + static inline Sign invertSign(Sign sign) { return sign == Negative ? Positive : Negative; } + + Sign sign() const { return m_data.sign(); } + + EncodedData m_data; +}; + +} // namespace blink + +namespace mozilla { +typedef blink::Decimal Decimal; +} // namespace mozilla + +#undef USING_FAST_MALLOC + +#ifdef DEFINED_ASSERT_FOR_DECIMAL_H +#undef DEFINED_ASSERT_FOR_DECIMAL_H +#undef ASSERT +#endif + +#endif // Decimal_h |