// // Copyright 2017 The Abseil Authors. // // 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 // // https://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. // This file contains :int128 implementation details that depend on internal // representation when ABSL_HAVE_INTRINSIC_INT128 is defined. This file is // included by int128.h and relies on ABSL_INTERNAL_WCHAR_T being defined. namespace int128_internal { // Casts from unsigned to signed while preserving the underlying binary // representation. constexpr __int128 BitCastToSigned(unsigned __int128 v) { // Casting an unsigned integer to a signed integer of the same // width is implementation defined behavior if the source value would not fit // in the destination type. We step around it with a roundtrip bitwise not // operation to make sure this function remains constexpr. Clang and GCC // optimize this to a no-op on x86-64. return v & (static_cast<unsigned __int128>(1) << 127) ? ~static_cast<__int128>(~v) : static_cast<__int128>(v); } } // namespace int128_internal inline int128& int128::operator=(__int128 v) { v_ = v; return *this; } constexpr uint64_t Int128Low64(int128 v) { return static_cast<uint64_t>(v.v_ & ~uint64_t{0}); } constexpr int64_t Int128High64(int128 v) { // Initially cast to unsigned to prevent a right shift on a negative value. return int128_internal::BitCastToSigned( static_cast<uint64_t>(static_cast<unsigned __int128>(v.v_) >> 64)); } constexpr int128::int128(int64_t high, uint64_t low) // Initially cast to unsigned to prevent a left shift that overflows. : v_(int128_internal::BitCastToSigned(static_cast<unsigned __int128>(high) << 64) | low) {} constexpr int128::int128(int v) : v_{v} {} constexpr int128::int128(long v) : v_{v} {} // NOLINT(runtime/int) constexpr int128::int128(long long v) : v_{v} {} // NOLINT(runtime/int) constexpr int128::int128(__int128 v) : v_{v} {} constexpr int128::int128(unsigned int v) : v_{v} {} constexpr int128::int128(unsigned long v) : v_{v} {} // NOLINT(runtime/int) // NOLINTNEXTLINE(runtime/int) constexpr int128::int128(unsigned long long v) : v_{v} {} constexpr int128::int128(unsigned __int128 v) : v_{static_cast<__int128>(v)} {} inline int128::int128(float v) { v_ = static_cast<__int128>(v); } inline int128::int128(double v) { v_ = static_cast<__int128>(v); } inline int128::int128(long double v) { v_ = static_cast<__int128>(v); } constexpr int128::int128(uint128 v) : v_{static_cast<__int128>(v)} {} constexpr int128::operator bool() const { return static_cast<bool>(v_); } constexpr int128::operator char() const { return static_cast<char>(v_); } constexpr int128::operator signed char() const { return static_cast<signed char>(v_); } constexpr int128::operator unsigned char() const { return static_cast<unsigned char>(v_); } constexpr int128::operator char16_t() const { return static_cast<char16_t>(v_); } constexpr int128::operator char32_t() const { return static_cast<char32_t>(v_); } constexpr int128::operator ABSL_INTERNAL_WCHAR_T() const { return static_cast<ABSL_INTERNAL_WCHAR_T>(v_); } constexpr int128::operator short() const { // NOLINT(runtime/int) return static_cast<short>(v_); // NOLINT(runtime/int) } constexpr int128::operator unsigned short() const { // NOLINT(runtime/int) return static_cast<unsigned short>(v_); // NOLINT(runtime/int) } constexpr int128::operator int() const { return static_cast<int>(v_); } constexpr int128::operator unsigned int() const { return static_cast<unsigned int>(v_); } constexpr int128::operator long() const { // NOLINT(runtime/int) return static_cast<long>(v_); // NOLINT(runtime/int) } constexpr int128::operator unsigned long() const { // NOLINT(runtime/int) return static_cast<unsigned long>(v_); // NOLINT(runtime/int) } constexpr int128::operator long long() const { // NOLINT(runtime/int) return static_cast<long long>(v_); // NOLINT(runtime/int) } constexpr int128::operator unsigned long long() const { // NOLINT(runtime/int) return static_cast<unsigned long long>(v_); // NOLINT(runtime/int) } constexpr int128::operator __int128() const { return v_; } constexpr int128::operator unsigned __int128() const { return static_cast<unsigned __int128>(v_); } // Clang on PowerPC sometimes produces incorrect __int128 to floating point // conversions. In that case, we do the conversion with a similar implementation // to the conversion operators in int128_no_intrinsic.inc. #if defined(__clang__) && !defined(__ppc64__) inline int128::operator float() const { return static_cast<float>(v_); } inline int128::operator double() const { return static_cast<double>(v_); } inline int128::operator long double() const { return static_cast<long double>(v_); } #else // Clang on PowerPC // Forward declaration for conversion operators to floating point types. constexpr int128 operator-(int128 v); constexpr bool operator!=(int128 lhs, int128 rhs); inline int128::operator float() const { // We must convert the absolute value and then negate as needed, because // floating point types are typically sign-magnitude. Otherwise, the // difference between the high and low 64 bits when interpreted as two's // complement overwhelms the precision of the mantissa. // // Also check to make sure we don't negate Int128Min() return v_ < 0 && *this != Int128Min() ? -static_cast<float>(-*this) : static_cast<float>(Int128Low64(*this)) + std::ldexp(static_cast<float>(Int128High64(*this)), 64); } inline int128::operator double() const { // See comment in int128::operator float() above. return v_ < 0 && *this != Int128Min() ? -static_cast<double>(-*this) : static_cast<double>(Int128Low64(*this)) + std::ldexp(static_cast<double>(Int128High64(*this)), 64); } inline int128::operator long double() const { // See comment in int128::operator float() above. return v_ < 0 && *this != Int128Min() ? -static_cast<long double>(-*this) : static_cast<long double>(Int128Low64(*this)) + std::ldexp(static_cast<long double>(Int128High64(*this)), 64); } #endif // Clang on PowerPC // Comparison operators. constexpr bool operator==(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) == static_cast<__int128>(rhs); } constexpr bool operator!=(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) != static_cast<__int128>(rhs); } constexpr bool operator<(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) < static_cast<__int128>(rhs); } constexpr bool operator>(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) > static_cast<__int128>(rhs); } constexpr bool operator<=(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) <= static_cast<__int128>(rhs); } constexpr bool operator>=(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) >= static_cast<__int128>(rhs); } // Unary operators. constexpr int128 operator-(int128 v) { return -static_cast<__int128>(v); } constexpr bool operator!(int128 v) { return !static_cast<__int128>(v); } constexpr int128 operator~(int128 val) { return ~static_cast<__int128>(val); } // Arithmetic operators. constexpr int128 operator+(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) + static_cast<__int128>(rhs); } constexpr int128 operator-(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) - static_cast<__int128>(rhs); } inline int128 operator*(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) * static_cast<__int128>(rhs); } inline int128 operator/(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) / static_cast<__int128>(rhs); } inline int128 operator%(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) % static_cast<__int128>(rhs); } inline int128 int128::operator++(int) { int128 tmp(*this); ++v_; return tmp; } inline int128 int128::operator--(int) { int128 tmp(*this); --v_; return tmp; } inline int128& int128::operator++() { ++v_; return *this; } inline int128& int128::operator--() { --v_; return *this; } constexpr int128 operator|(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) | static_cast<__int128>(rhs); } constexpr int128 operator&(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) & static_cast<__int128>(rhs); } constexpr int128 operator^(int128 lhs, int128 rhs) { return static_cast<__int128>(lhs) ^ static_cast<__int128>(rhs); } constexpr int128 operator<<(int128 lhs, int amount) { return static_cast<__int128>(lhs) << amount; } constexpr int128 operator>>(int128 lhs, int amount) { return static_cast<__int128>(lhs) >> amount; }