diff options
Diffstat (limited to 'absl/numeric/int128.h')
| -rw-r--r-- | absl/numeric/int128.h | 94 |
1 files changed, 81 insertions, 13 deletions
diff --git a/absl/numeric/int128.h b/absl/numeric/int128.h index 96f42a83..cb4776f1 100644 --- a/absl/numeric/int128.h +++ b/absl/numeric/int128.h @@ -31,13 +31,19 @@ #include <cstring> #include <iosfwd> #include <limits> +#include <utility> #include "absl/base/config.h" #include "absl/base/macros.h" #include "absl/base/port.h" +#if defined(_MSC_VER) && defined(_WIN64) +#include <intrin.h> +#pragma intrinsic(_umul128) +#endif // defined(_MSC_VER) && defined(_WIN64) + namespace absl { -inline namespace lts_2018_06_20 { +inline namespace lts_2018_12_18 { // uint128 @@ -192,6 +198,12 @@ class // Returns the highest value for a 128-bit unsigned integer. friend constexpr uint128 Uint128Max(); + // Support for absl::Hash. + template <typename H> + friend H AbslHashValue(H h, uint128 v) { + return H::combine(std::move(h), Uint128High64(v), Uint128Low64(v)); + } + private: constexpr uint128(uint64_t high, uint64_t low); @@ -220,21 +232,71 @@ std::ostream& operator<<(std::ostream& os, uint128 v); // TODO(strel) add operator>>(std::istream&, uint128) +constexpr uint128 Uint128Max() { + return uint128((std::numeric_limits<uint64_t>::max)(), + (std::numeric_limits<uint64_t>::max)()); +} + +} // inline namespace lts_2018_12_18 +} // namespace absl + +// Specialized numeric_limits for uint128. +namespace std { +template <> +class numeric_limits<absl::uint128> { + public: + static constexpr bool is_specialized = true; + static constexpr bool is_signed = false; + static constexpr bool is_integer = true; + static constexpr bool is_exact = true; + static constexpr bool has_infinity = false; + static constexpr bool has_quiet_NaN = false; + static constexpr bool has_signaling_NaN = false; + static constexpr float_denorm_style has_denorm = denorm_absent; + static constexpr bool has_denorm_loss = false; + static constexpr float_round_style round_style = round_toward_zero; + static constexpr bool is_iec559 = false; + static constexpr bool is_bounded = true; + static constexpr bool is_modulo = true; + static constexpr int digits = 128; + static constexpr int digits10 = 38; + static constexpr int max_digits10 = 0; + static constexpr int radix = 2; + static constexpr int min_exponent = 0; + static constexpr int min_exponent10 = 0; + static constexpr int max_exponent = 0; + static constexpr int max_exponent10 = 0; +#ifdef ABSL_HAVE_INTRINSIC_INT128 + static constexpr bool traps = numeric_limits<unsigned __int128>::traps; +#else // ABSL_HAVE_INTRINSIC_INT128 + static constexpr bool traps = numeric_limits<uint64_t>::traps; +#endif // ABSL_HAVE_INTRINSIC_INT128 + static constexpr bool tinyness_before = false; + + static constexpr absl::uint128 min() { return 0; } + static constexpr absl::uint128 lowest() { return 0; } + static constexpr absl::uint128 max() { return absl::Uint128Max(); } + static constexpr absl::uint128 epsilon() { return 0; } + static constexpr absl::uint128 round_error() { return 0; } + static constexpr absl::uint128 infinity() { return 0; } + static constexpr absl::uint128 quiet_NaN() { return 0; } + static constexpr absl::uint128 signaling_NaN() { return 0; } + static constexpr absl::uint128 denorm_min() { return 0; } +}; +} // namespace std + // TODO(absl-team): Implement signed 128-bit type // -------------------------------------------------------------------------- // Implementation details follow // -------------------------------------------------------------------------- +namespace absl { +inline namespace lts_2018_12_18 { constexpr uint128 MakeUint128(uint64_t high, uint64_t low) { return uint128(high, low); } -constexpr uint128 Uint128Max() { - return uint128(std::numeric_limits<uint64_t>::max(), - std::numeric_limits<uint64_t>::max()); -} - // Assignment from integer types. inline uint128& uint128::operator=(int v) { return *this = uint128(v); } @@ -330,13 +392,13 @@ constexpr uint128::uint128(uint64_t high, uint64_t low) constexpr uint128::uint128(int v) : lo_{static_cast<uint64_t>(v)}, - hi_{v < 0 ? std::numeric_limits<uint64_t>::max() : 0} {} + hi_{v < 0 ? (std::numeric_limits<uint64_t>::max)() : 0} {} constexpr uint128::uint128(long v) // NOLINT(runtime/int) : lo_{static_cast<uint64_t>(v)}, - hi_{v < 0 ? std::numeric_limits<uint64_t>::max() : 0} {} + hi_{v < 0 ? (std::numeric_limits<uint64_t>::max)() : 0} {} constexpr uint128::uint128(long long v) // NOLINT(runtime/int) : lo_{static_cast<uint64_t>(v)}, - hi_{v < 0 ? std::numeric_limits<uint64_t>::max() : 0} {} + hi_{v < 0 ? (std::numeric_limits<uint64_t>::max)() : 0} {} constexpr uint128::uint128(unsigned int v) : lo_{v}, hi_{0} {} // NOLINTNEXTLINE(runtime/int) @@ -359,13 +421,13 @@ constexpr uint128::uint128(uint64_t high, uint64_t low) : hi_{high}, lo_{low} {} constexpr uint128::uint128(int v) - : hi_{v < 0 ? std::numeric_limits<uint64_t>::max() : 0}, + : hi_{v < 0 ? (std::numeric_limits<uint64_t>::max)() : 0}, lo_{static_cast<uint64_t>(v)} {} constexpr uint128::uint128(long v) // NOLINT(runtime/int) - : hi_{v < 0 ? std::numeric_limits<uint64_t>::max() : 0}, + : hi_{v < 0 ? (std::numeric_limits<uint64_t>::max)() : 0}, lo_{static_cast<uint64_t>(v)} {} constexpr uint128::uint128(long long v) // NOLINT(runtime/int) - : hi_{v < 0 ? std::numeric_limits<uint64_t>::max() : 0}, + : hi_{v < 0 ? (std::numeric_limits<uint64_t>::max)() : 0}, lo_{static_cast<uint64_t>(v)} {} constexpr uint128::uint128(unsigned int v) : hi_{0}, lo_{v} {} @@ -607,6 +669,12 @@ inline uint128 operator*(uint128 lhs, uint128 rhs) { // can be used for uint128 storage. return static_cast<unsigned __int128>(lhs) * static_cast<unsigned __int128>(rhs); +#elif defined(_MSC_VER) && defined(_WIN64) + uint64_t carry; + uint64_t low = _umul128(Uint128Low64(lhs), Uint128Low64(rhs), &carry); + return MakeUint128(Uint128Low64(lhs) * Uint128High64(rhs) + + Uint128High64(lhs) * Uint128Low64(rhs) + carry, + low); #else // ABSL_HAVE_INTRINSIC128 uint64_t a32 = Uint128Low64(lhs) >> 32; uint64_t a00 = Uint128Low64(lhs) & 0xffffffff; @@ -652,7 +720,7 @@ inline uint128& uint128::operator--() { #include "absl/numeric/int128_no_intrinsic.inc" #endif // ABSL_HAVE_INTRINSIC_INT128 -} // inline namespace lts_2018_06_20 +} // inline namespace lts_2018_12_18 } // namespace absl #endif // ABSL_NUMERIC_INT128_H_ |