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-rw-r--r--absl/numeric/int128_no_intrinsic.inc290
1 files changed, 290 insertions, 0 deletions
diff --git a/absl/numeric/int128_no_intrinsic.inc b/absl/numeric/int128_no_intrinsic.inc
index 046cb9b3..c753771a 100644
--- a/absl/numeric/int128_no_intrinsic.inc
+++ b/absl/numeric/int128_no_intrinsic.inc
@@ -16,3 +16,293 @@
// This file contains :int128 implementation details that depend on internal
// representation when ABSL_HAVE_INTRINSIC_INT128 is *not* defined. This file
// is included by int128.h and relies on ABSL_INTERNAL_WCHAR_T being defined.
+
+constexpr uint64_t Int128Low64(int128 v) { return v.lo_; }
+
+constexpr int64_t Int128High64(int128 v) { return v.hi_; }
+
+#if defined(ABSL_IS_LITTLE_ENDIAN)
+
+constexpr int128::int128(int64_t high, uint64_t low) :
+ lo_(low), hi_(high) {}
+
+constexpr int128::int128(int v)
+ : lo_{static_cast<uint64_t>(v)}, hi_{v < 0 ? ~int64_t{0} : 0} {}
+constexpr int128::int128(long v) // NOLINT(runtime/int)
+ : lo_{static_cast<uint64_t>(v)}, hi_{v < 0 ? ~int64_t{0} : 0} {}
+constexpr int128::int128(long long v) // NOLINT(runtime/int)
+ : lo_{static_cast<uint64_t>(v)}, hi_{v < 0 ? ~int64_t{0} : 0} {}
+
+constexpr int128::int128(unsigned int v) : lo_{v}, hi_{0} {}
+// NOLINTNEXTLINE(runtime/int)
+constexpr int128::int128(unsigned long v) : lo_{v}, hi_{0} {}
+// NOLINTNEXTLINE(runtime/int)
+constexpr int128::int128(unsigned long long v) : lo_{v}, hi_{0} {}
+
+constexpr int128::int128(uint128 v)
+ : lo_{Uint128Low64(v)}, hi_{static_cast<int64_t>(Uint128High64(v))} {}
+
+#elif defined(ABSL_IS_BIG_ENDIAN)
+
+constexpr int128::int128(int64_t high, uint64_t low) :
+ hi_{high}, lo_{low} {}
+
+constexpr int128::int128(int v)
+ : hi_{v < 0 ? ~int64_t{0} : 0}, lo_{static_cast<uint64_t>(v)} {}
+constexpr int128::int128(long v) // NOLINT(runtime/int)
+ : hi_{v < 0 ? ~int64_t{0} : 0}, lo_{static_cast<uint64_t>(v)} {}
+constexpr int128::int128(long long v) // NOLINT(runtime/int)
+ : hi_{v < 0 ? ~int64_t{0} : 0}, lo_{static_cast<uint64_t>(v)} {}
+
+constexpr int128::int128(unsigned int v) : hi_{0}, lo_{v} {}
+// NOLINTNEXTLINE(runtime/int)
+constexpr int128::int128(unsigned long v) : hi_{0}, lo_{v} {}
+// NOLINTNEXTLINE(runtime/int)
+constexpr int128::int128(unsigned long long v) : hi_{0}, lo_{v} {}
+
+constexpr int128::int128(uint128 v)
+ : hi_{static_cast<int64_t>(Uint128High64(v))}, lo_{Uint128Low64(v)} {}
+
+#else // byte order
+#error "Unsupported byte order: must be little-endian or big-endian."
+#endif // byte order
+
+constexpr int128::operator bool() const { return lo_ || hi_; }
+
+constexpr int128::operator char() const {
+ // NOLINTNEXTLINE(runtime/int)
+ return static_cast<char>(static_cast<long long>(*this));
+}
+
+constexpr int128::operator signed char() const {
+ // NOLINTNEXTLINE(runtime/int)
+ return static_cast<signed char>(static_cast<long long>(*this));
+}
+
+constexpr int128::operator unsigned char() const {
+ return static_cast<unsigned char>(lo_);
+}
+
+constexpr int128::operator char16_t() const {
+ return static_cast<char16_t>(lo_);
+}
+
+constexpr int128::operator char32_t() const {
+ return static_cast<char32_t>(lo_);
+}
+
+constexpr int128::operator ABSL_INTERNAL_WCHAR_T() const {
+ // NOLINTNEXTLINE(runtime/int)
+ return static_cast<ABSL_INTERNAL_WCHAR_T>(static_cast<long long>(*this));
+}
+
+constexpr int128::operator short() const { // NOLINT(runtime/int)
+ // NOLINTNEXTLINE(runtime/int)
+ return static_cast<short>(static_cast<long long>(*this));
+}
+
+constexpr int128::operator unsigned short() const { // NOLINT(runtime/int)
+ return static_cast<unsigned short>(lo_); // NOLINT(runtime/int)
+}
+
+constexpr int128::operator int() const {
+ // NOLINTNEXTLINE(runtime/int)
+ return static_cast<int>(static_cast<long long>(*this));
+}
+
+constexpr int128::operator unsigned int() const {
+ return static_cast<unsigned int>(lo_);
+}
+
+constexpr int128::operator long() const { // NOLINT(runtime/int)
+ // NOLINTNEXTLINE(runtime/int)
+ return static_cast<long>(static_cast<long long>(*this));
+}
+
+constexpr int128::operator unsigned long() const { // NOLINT(runtime/int)
+ return static_cast<unsigned long>(lo_); // NOLINT(runtime/int)
+}
+
+constexpr int128::operator long long() const { // NOLINT(runtime/int)
+ // We don't bother checking the value of hi_. If *this < 0, lo_'s high bit
+ // must be set in order for the value to fit into a long long. Conversely, if
+ // lo_'s high bit is set, *this must be < 0 for the value to fit.
+ return int128_internal::BitCastToSigned(lo_);
+}
+
+constexpr int128::operator unsigned long long() const { // NOLINT(runtime/int)
+ return static_cast<unsigned long long>(lo_); // NOLINT(runtime/int)
+}
+
+// Forward declaration for conversion operators to floating point types.
+int128 operator-(int128 v);
+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 hi_ < 0 && *this != Int128Min()
+ ? -static_cast<float>(-*this)
+ : static_cast<float>(lo_) +
+ std::ldexp(static_cast<float>(hi_), 64);
+}
+
+inline int128::operator double() const {
+ // See comment in int128::operator float() above.
+ return hi_ < 0 && *this != Int128Min()
+ ? -static_cast<double>(-*this)
+ : static_cast<double>(lo_) +
+ std::ldexp(static_cast<double>(hi_), 64);
+}
+
+inline int128::operator long double() const {
+ // See comment in int128::operator float() above.
+ return hi_ < 0 && *this != Int128Min()
+ ? -static_cast<long double>(-*this)
+ : static_cast<long double>(lo_) +
+ std::ldexp(static_cast<long double>(hi_), 64);
+}
+
+// Comparison operators.
+
+inline bool operator==(int128 lhs, int128 rhs) {
+ return (Int128Low64(lhs) == Int128Low64(rhs) &&
+ Int128High64(lhs) == Int128High64(rhs));
+}
+
+inline bool operator!=(int128 lhs, int128 rhs) {
+ return !(lhs == rhs);
+}
+
+inline bool operator<(int128 lhs, int128 rhs) {
+ return (Int128High64(lhs) == Int128High64(rhs))
+ ? (Int128Low64(lhs) < Int128Low64(rhs))
+ : (Int128High64(lhs) < Int128High64(rhs));
+}
+
+inline bool operator>(int128 lhs, int128 rhs) {
+ return (Int128High64(lhs) == Int128High64(rhs))
+ ? (Int128Low64(lhs) > Int128Low64(rhs))
+ : (Int128High64(lhs) > Int128High64(rhs));
+}
+
+inline bool operator<=(int128 lhs, int128 rhs) {
+ return !(lhs > rhs);
+}
+
+inline bool operator>=(int128 lhs, int128 rhs) {
+ return !(lhs < rhs);
+}
+
+// Unary operators.
+
+inline int128 operator-(int128 v) {
+ int64_t hi = ~Int128High64(v);
+ uint64_t lo = ~Int128Low64(v) + 1;
+ if (lo == 0) ++hi; // carry
+ return MakeInt128(hi, lo);
+}
+
+inline bool operator!(int128 v) {
+ return !Int128Low64(v) && !Int128High64(v);
+}
+
+inline int128 operator~(int128 val) {
+ return MakeInt128(~Int128High64(val), ~Int128Low64(val));
+}
+
+// Arithmetic operators.
+
+inline int128 operator+(int128 lhs, int128 rhs) {
+ int128 result = MakeInt128(Int128High64(lhs) + Int128High64(rhs),
+ Int128Low64(lhs) + Int128Low64(rhs));
+ if (Int128Low64(result) < Int128Low64(lhs)) { // check for carry
+ return MakeInt128(Int128High64(result) + 1, Int128Low64(result));
+ }
+ return result;
+}
+
+inline int128 operator-(int128 lhs, int128 rhs) {
+ int128 result = MakeInt128(Int128High64(lhs) - Int128High64(rhs),
+ Int128Low64(lhs) - Int128Low64(rhs));
+ if (Int128Low64(lhs) < Int128Low64(rhs)) { // check for carry
+ return MakeInt128(Int128High64(result) - 1, Int128Low64(result));
+ }
+ return result;
+}
+
+inline int128 operator*(int128 lhs, int128 rhs) {
+ uint128 result = uint128(lhs) * rhs;
+ return MakeInt128(int128_internal::BitCastToSigned(Uint128High64(result)),
+ Uint128Low64(result));
+}
+
+inline int128 int128::operator++(int) {
+ int128 tmp(*this);
+ *this += 1;
+ return tmp;
+}
+
+inline int128 int128::operator--(int) {
+ int128 tmp(*this);
+ *this -= 1;
+ return tmp;
+}
+
+inline int128& int128::operator++() {
+ *this += 1;
+ return *this;
+}
+
+inline int128& int128::operator--() {
+ *this -= 1;
+ return *this;
+}
+
+inline int128 operator|(int128 lhs, int128 rhs) {
+ return MakeInt128(Int128High64(lhs) | Int128High64(rhs),
+ Int128Low64(lhs) | Int128Low64(rhs));
+}
+
+inline int128 operator&(int128 lhs, int128 rhs) {
+ return MakeInt128(Int128High64(lhs) & Int128High64(rhs),
+ Int128Low64(lhs) & Int128Low64(rhs));
+}
+
+inline int128 operator^(int128 lhs, int128 rhs) {
+ return MakeInt128(Int128High64(lhs) ^ Int128High64(rhs),
+ Int128Low64(lhs) ^ Int128Low64(rhs));
+}
+
+inline int128 operator<<(int128 lhs, int amount) {
+ // uint64_t shifts of >= 64 are undefined, so we need some special-casing.
+ if (amount < 64) {
+ if (amount != 0) {
+ return MakeInt128(
+ (Int128High64(lhs) << amount) |
+ static_cast<int64_t>(Int128Low64(lhs) >> (64 - amount)),
+ Int128Low64(lhs) << amount);
+ }
+ return lhs;
+ }
+ return MakeInt128(static_cast<int64_t>(Int128Low64(lhs) << (amount - 64)), 0);
+}
+
+inline int128 operator>>(int128 lhs, int amount) {
+ // uint64_t shifts of >= 64 are undefined, so we need some special-casing.
+ if (amount < 64) {
+ if (amount != 0) {
+ return MakeInt128(
+ Int128High64(lhs) >> amount,
+ (Int128Low64(lhs) >> amount) |
+ (static_cast<uint64_t>(Int128High64(lhs)) << (64 - amount)));
+ }
+ return lhs;
+ }
+ return MakeInt128(0,
+ static_cast<uint64_t>(Int128High64(lhs) >> (amount - 64)));
+}