Export of internal Abseil changes

--
d447fdcb801036cf08197eece193a5a706661120 by Gennadiy Rozental <rogeeff@google.com>:

Eliminate the need for static function holding help message. This decreases the cost of ABSL_FLAG abstraction by 120 bytes under clang.

PiperOrigin-RevId: 281107806

--
0aa6b91189f0e8b2381438c33465673a7ae02487 by Derek Mauro <dmauro@google.com>:

Disable the weak symbol CCTZ extension in the time test_util
on MinGW, which does not support it.

PiperOrigin-RevId: 280719769

--
67322c41c3e776eb541de90fa4526bdb49422eb6 by Abseil Team <absl-team@google.com>:

Tune PeriodicSampler implementation (for internal-use only)

PiperOrigin-RevId: 280708943

--
3a48c346340c7ed03816645cd327e1ff07729aa4 by Abseil Team <absl-team@google.com>:

Clean up public headers not to have warnings for "-Wcomma"

PiperOrigin-RevId: 280695373

--
981acd1ef3b13a83a84f04f11c8931f4ed4451c9 by Matthew Brown <matthewbr@google.com>:

Release absl::int128.

PiperOrigin-RevId: 280690817

--
d30fae9d2ec30b81322d2eb5afe7e13e45b4b422 by Derek Mauro <dmauro@google.com>:

Fix -Wundef warnings in random platform detection

PiperOrigin-RevId: 280669598
GitOrigin-RevId: d447fdcb801036cf08197eece193a5a706661120
Change-Id: Ie5e10e567c54b7de211833607689f233d4ddf734

1 files changed, 743 insertions, 0 deletions

diff --git a/absl/numeric/int128_test.cc b/absl/numeric/int128_test.cc
index 5e1b5ec352b0..bc86c714acce 100644
--- a/absl/numeric/int128_test.cc
+++ b/absl/numeric/int128_test.cc
@@ -479,4 +479,747 @@ TEST(Uint128, Hash) {
   }));
 }
 
+
+TEST(Int128Uint128, ConversionTest) {
+  absl::int128 nonnegative_signed_values[] = {
+      0,
+      1,
+      0xffeeddccbbaa9988,
+      absl::MakeInt128(0x7766554433221100, 0),
+      absl::MakeInt128(0x1234567890abcdef, 0xfedcba0987654321),
+      absl::Int128Max()};
+  for (absl::int128 value : nonnegative_signed_values) {
+    EXPECT_EQ(value, absl::int128(absl::uint128(value)));
+
+    absl::uint128 assigned_value;
+    assigned_value = value;
+    EXPECT_EQ(value, absl::int128(assigned_value));
+  }
+
+  absl::int128 negative_values[] = {
+      -1, -0x1234567890abcdef,
+      absl::MakeInt128(-0x5544332211ffeedd, 0),
+      -absl::MakeInt128(0x76543210fedcba98, 0xabcdef0123456789)};
+  for (absl::int128 value : negative_values) {
+    EXPECT_EQ(absl::uint128(-value), -absl::uint128(value));
+
+    absl::uint128 assigned_value;
+    assigned_value = value;
+    EXPECT_EQ(absl::uint128(-value), -assigned_value);
+  }
+}
+
+template <typename T>
+class Int128IntegerTraitsTest : public ::testing::Test {};
+
+TYPED_TEST_SUITE(Int128IntegerTraitsTest, IntegerTypes);
+
+TYPED_TEST(Int128IntegerTraitsTest, ConstructAssignTest) {
+  static_assert(std::is_constructible<absl::int128, TypeParam>::value,
+                "absl::int128 must be constructible from TypeParam");
+  static_assert(std::is_assignable<absl::int128&, TypeParam>::value,
+                "absl::int128 must be assignable from TypeParam");
+  static_assert(!std::is_assignable<TypeParam&, absl::int128>::value,
+                "TypeParam must not be assignable from absl::int128");
+}
+
+template <typename T>
+class Int128FloatTraitsTest : public ::testing::Test {};
+
+TYPED_TEST_SUITE(Int128FloatTraitsTest, FloatingPointTypes);
+
+TYPED_TEST(Int128FloatTraitsTest, ConstructAssignTest) {
+  static_assert(std::is_constructible<absl::int128, TypeParam>::value,
+                "absl::int128 must be constructible from TypeParam");
+  static_assert(!std::is_assignable<absl::int128&, TypeParam>::value,
+                "absl::int128 must not be assignable from TypeParam");
+  static_assert(!std::is_assignable<TypeParam&, absl::int128>::value,
+                "TypeParam must not be assignable from absl::int128");
+}
+
+#ifdef ABSL_HAVE_INTRINSIC_INT128
+// These type traits done separately as TYPED_TEST requires typeinfo, and not
+// all platforms have this for __int128 even though they define the type.
+TEST(Int128, IntrinsicTypeTraitsTest) {
+  static_assert(std::is_constructible<absl::int128, __int128>::value,
+                "absl::int128 must be constructible from __int128");
+  static_assert(std::is_assignable<absl::int128&, __int128>::value,
+                "absl::int128 must be assignable from __int128");
+  static_assert(!std::is_assignable<__int128&, absl::int128>::value,
+                "__int128 must not be assignable from absl::int128");
+
+  static_assert(std::is_constructible<absl::int128, unsigned __int128>::value,
+                "absl::int128 must be constructible from unsigned __int128");
+  static_assert(!std::is_assignable<absl::int128&, unsigned __int128>::value,
+                "absl::int128 must be assignable from unsigned __int128");
+  static_assert(!std::is_assignable<unsigned __int128&, absl::int128>::value,
+                "unsigned __int128 must not be assignable from absl::int128");
+}
+#endif  // ABSL_HAVE_INTRINSIC_INT128
+
+TEST(Int128, TrivialTraitsTest) {
+  static_assert(absl::is_trivially_default_constructible<absl::int128>::value,
+                "");
+  static_assert(absl::is_trivially_copy_constructible<absl::int128>::value, "");
+  static_assert(absl::is_trivially_copy_assignable<absl::int128>::value, "");
+  static_assert(std::is_trivially_destructible<absl::int128>::value, "");
+}
+
+TEST(Int128, BoolConversionTest) {
+  EXPECT_FALSE(absl::int128(0));
+  for (int i = 0; i < 64; ++i) {
+    EXPECT_TRUE(absl::MakeInt128(0, uint64_t{1} << i));
+  }
+  for (int i = 0; i < 63; ++i) {
+    EXPECT_TRUE(absl::MakeInt128(int64_t{1} << i, 0));
+  }
+  EXPECT_TRUE(absl::Int128Min());
+
+  EXPECT_EQ(absl::int128(1), absl::int128(true));
+  EXPECT_EQ(absl::int128(0), absl::int128(false));
+}
+
+template <typename T>
+class Int128IntegerConversionTest : public ::testing::Test {};
+
+TYPED_TEST_SUITE(Int128IntegerConversionTest, IntegerTypes);
+
+TYPED_TEST(Int128IntegerConversionTest, RoundTripTest) {
+  EXPECT_EQ(TypeParam{0}, static_cast<TypeParam>(absl::int128(0)));
+  EXPECT_EQ(std::numeric_limits<TypeParam>::min(),
+            static_cast<TypeParam>(
+                absl::int128(std::numeric_limits<TypeParam>::min())));
+  EXPECT_EQ(std::numeric_limits<TypeParam>::max(),
+            static_cast<TypeParam>(
+                absl::int128(std::numeric_limits<TypeParam>::max())));
+}
+
+template <typename T>
+class Int128FloatConversionTest : public ::testing::Test {};
+
+TYPED_TEST_SUITE(Int128FloatConversionTest, FloatingPointTypes);
+
+TYPED_TEST(Int128FloatConversionTest, ConstructAndCastTest) {
+  // Conversions where the floating point values should be exactly the same.
+  // 0x9f5b is a randomly chosen small value.
+  for (int i = 0; i < 110; ++i) {  // 110 = 126 - #bits in 0x9f5b
+    SCOPED_TRACE(::testing::Message() << "i = " << i);
+
+    TypeParam float_value = std::ldexp(static_cast<TypeParam>(0x9f5b), i);
+    absl::int128 int_value = absl::int128(0x9f5b) << i;
+
+    EXPECT_EQ(float_value, static_cast<TypeParam>(int_value));
+    EXPECT_EQ(-float_value, static_cast<TypeParam>(-int_value));
+    EXPECT_EQ(int_value, absl::int128(float_value));
+    EXPECT_EQ(-int_value, absl::int128(-float_value));
+  }
+
+  // Round trip conversions with a small sample of randomly generated uint64_t
+  // values (less than int64_t max so that value * 2^64 fits into int128).
+  uint64_t values[] = {0x6d4492c24fb86199, 0x26ead65e4cb359b5,
+                       0x2c43407433ba3fd1, 0x3b574ec668df6b55,
+                       0x1c750e55a29f4f0f};
+  for (uint64_t value : values) {
+    for (int i = 0; i <= 64; ++i) {
+      SCOPED_TRACE(::testing::Message()
+                   << "value = " << value << "; i = " << i);
+
+      TypeParam fvalue = std::ldexp(static_cast<TypeParam>(value), i);
+      EXPECT_DOUBLE_EQ(fvalue, static_cast<TypeParam>(absl::int128(fvalue)));
+      EXPECT_DOUBLE_EQ(-fvalue, static_cast<TypeParam>(-absl::int128(fvalue)));
+      EXPECT_DOUBLE_EQ(-fvalue, static_cast<TypeParam>(absl::int128(-fvalue)));
+      EXPECT_DOUBLE_EQ(fvalue, static_cast<TypeParam>(-absl::int128(-fvalue)));
+    }
+  }
+
+  // Round trip conversions with a small sample of random large positive values.
+  absl::int128 large_values[] = {
+      absl::MakeInt128(0x5b0640d96c7b3d9f, 0xb7a7189e51d18622),
+      absl::MakeInt128(0x34bed042c6f65270, 0x73b236570669a089),
+      absl::MakeInt128(0x43deba9e6da12724, 0xf7f0f83da686797d),
+      absl::MakeInt128(0x71e8d383be4e5589, 0x75c3f96fb00752b6)};
+  for (absl::int128 value : large_values) {
+    // Make value have as many significant bits as can be represented by
+    // the mantissa, also making sure the highest and lowest bit in the range
+    // are set.
+    value >>= (127 - std::numeric_limits<TypeParam>::digits);
+    value |= absl::int128(1) << (std::numeric_limits<TypeParam>::digits - 1);
+    value |= 1;
+    for (int i = 0; i < 127 - std::numeric_limits<TypeParam>::digits; ++i) {
+      absl::int128 int_value = value << i;
+      EXPECT_EQ(int_value,
+                static_cast<absl::int128>(static_cast<TypeParam>(int_value)));
+      EXPECT_EQ(-int_value,
+                static_cast<absl::int128>(static_cast<TypeParam>(-int_value)));
+    }
+  }
+
+  // Small sample of checks that rounding is toward zero
+  EXPECT_EQ(0, absl::int128(TypeParam(0.1)));
+  EXPECT_EQ(17, absl::int128(TypeParam(17.8)));
+  EXPECT_EQ(0, absl::int128(TypeParam(-0.8)));
+  EXPECT_EQ(-53, absl::int128(TypeParam(-53.1)));
+  EXPECT_EQ(0, absl::int128(TypeParam(0.5)));
+  EXPECT_EQ(0, absl::int128(TypeParam(-0.5)));
+  TypeParam just_lt_one = std::nexttoward(TypeParam(1), TypeParam(0));
+  EXPECT_EQ(0, absl::int128(just_lt_one));
+  TypeParam just_gt_minus_one = std::nexttoward(TypeParam(-1), TypeParam(0));
+  EXPECT_EQ(0, absl::int128(just_gt_minus_one));
+
+  // Check limits
+  EXPECT_DOUBLE_EQ(std::ldexp(static_cast<TypeParam>(1), 127),
+                   static_cast<TypeParam>(absl::Int128Max()));
+  EXPECT_DOUBLE_EQ(-std::ldexp(static_cast<TypeParam>(1), 127),
+                   static_cast<TypeParam>(absl::Int128Min()));
+}
+
+TEST(Int128, FactoryTest) {
+  EXPECT_EQ(absl::int128(-1), absl::MakeInt128(-1, -1));
+  EXPECT_EQ(absl::int128(-31), absl::MakeInt128(-1, -31));
+  EXPECT_EQ(absl::int128(std::numeric_limits<int64_t>::min()),
+            absl::MakeInt128(-1, std::numeric_limits<int64_t>::min()));
+  EXPECT_EQ(absl::int128(0), absl::MakeInt128(0, 0));
+  EXPECT_EQ(absl::int128(1), absl::MakeInt128(0, 1));
+  EXPECT_EQ(absl::int128(std::numeric_limits<int64_t>::max()),
+            absl::MakeInt128(0, std::numeric_limits<int64_t>::max()));
+}
+
+TEST(Int128, HighLowTest) {
+  struct HighLowPair {
+    int64_t high;
+    uint64_t low;
+  };
+  HighLowPair values[]{{0, 0}, {0, 1}, {1, 0}, {123, 456}, {-654, 321}};
+  for (const HighLowPair& pair : values) {
+    absl::int128 value = absl::MakeInt128(pair.high, pair.low);
+    EXPECT_EQ(pair.low, absl::Int128Low64(value));
+    EXPECT_EQ(pair.high, absl::Int128High64(value));
+  }
+}
+
+TEST(Int128, LimitsTest) {
+  EXPECT_EQ(absl::MakeInt128(0x7fffffffffffffff, 0xffffffffffffffff),
+            absl::Int128Max());
+  EXPECT_EQ(absl::Int128Max(), ~absl::Int128Min());
+}
+
+#if defined(ABSL_HAVE_INTRINSIC_INT128)
+TEST(Int128, IntrinsicConversionTest) {
+  __int128 intrinsic =
+      (static_cast<__int128>(0x3a5b76c209de76f6) << 64) + 0x1f25e1d63a2b46c5;
+  absl::int128 custom =
+      absl::MakeInt128(0x3a5b76c209de76f6, 0x1f25e1d63a2b46c5);
+
+  EXPECT_EQ(custom, absl::int128(intrinsic));
+  EXPECT_EQ(intrinsic, static_cast<__int128>(custom));
+}
+#endif  // ABSL_HAVE_INTRINSIC_INT128
+
+TEST(Int128, ConstexprTest) {
+  constexpr absl::int128 zero = absl::int128();
+  constexpr absl::int128 one = 1;
+  constexpr absl::int128 minus_two = -2;
+  constexpr absl::int128 min = absl::Int128Min();
+  constexpr absl::int128 max = absl::Int128Max();
+  EXPECT_EQ(zero, absl::int128(0));
+  EXPECT_EQ(one, absl::int128(1));
+  EXPECT_EQ(minus_two, absl::MakeInt128(-1, -2));
+  EXPECT_GT(max, one);
+  EXPECT_LT(min, minus_two);
+}
+
+TEST(Int128, ComparisonTest) {
+  struct TestCase {
+    absl::int128 smaller;
+    absl::int128 larger;
+  };
+  TestCase cases[] = {
+      {absl::int128(0), absl::int128(123)},
+      {absl::MakeInt128(-12, 34), absl::MakeInt128(12, 34)},
+      {absl::MakeInt128(1, 1000), absl::MakeInt128(1000, 1)},
+      {absl::MakeInt128(-1000, 1000), absl::MakeInt128(-1, 1)},
+  };
+  for (const TestCase& pair : cases) {
+    SCOPED_TRACE(::testing::Message() << "pair.smaller = " << pair.smaller
+                                      << "; pair.larger = " << pair.larger);
+
+    EXPECT_TRUE(pair.smaller == pair.smaller);  // NOLINT(readability/check)
+    EXPECT_TRUE(pair.larger == pair.larger);    // NOLINT(readability/check)
+    EXPECT_FALSE(pair.smaller == pair.larger);  // NOLINT(readability/check)
+
+    EXPECT_TRUE(pair.smaller != pair.larger);    // NOLINT(readability/check)
+    EXPECT_FALSE(pair.smaller != pair.smaller);  // NOLINT(readability/check)
+    EXPECT_FALSE(pair.larger != pair.larger);    // NOLINT(readability/check)
+
+    EXPECT_TRUE(pair.smaller < pair.larger);   // NOLINT(readability/check)
+    EXPECT_FALSE(pair.larger < pair.smaller);  // NOLINT(readability/check)
+
+    EXPECT_TRUE(pair.larger > pair.smaller);   // NOLINT(readability/check)
+    EXPECT_FALSE(pair.smaller > pair.larger);  // NOLINT(readability/check)
+
+    EXPECT_TRUE(pair.smaller <= pair.larger);   // NOLINT(readability/check)
+    EXPECT_FALSE(pair.larger <= pair.smaller);  // NOLINT(readability/check)
+    EXPECT_TRUE(pair.smaller <= pair.smaller);  // NOLINT(readability/check)
+    EXPECT_TRUE(pair.larger <= pair.larger);    // NOLINT(readability/check)
+
+    EXPECT_TRUE(pair.larger >= pair.smaller);   // NOLINT(readability/check)
+    EXPECT_FALSE(pair.smaller >= pair.larger);  // NOLINT(readability/check)
+    EXPECT_TRUE(pair.smaller >= pair.smaller);  // NOLINT(readability/check)
+    EXPECT_TRUE(pair.larger >= pair.larger);    // NOLINT(readability/check)
+  }
+}
+
+TEST(Int128, UnaryNegationTest) {
+  int64_t values64[] = {0, 1, 12345, 0x4000000000000000,
+                        std::numeric_limits<int64_t>::max()};
+  for (int64_t value : values64) {
+    SCOPED_TRACE(::testing::Message() << "value = " << value);
+
+    EXPECT_EQ(absl::int128(-value), -absl::int128(value));
+    EXPECT_EQ(absl::int128(value), -absl::int128(-value));
+    EXPECT_EQ(absl::MakeInt128(-value, 0), -absl::MakeInt128(value, 0));
+    EXPECT_EQ(absl::MakeInt128(value, 0), -absl::MakeInt128(-value, 0));
+  }
+}
+
+TEST(Int128, LogicalNotTest) {
+  EXPECT_TRUE(!absl::int128(0));
+  for (int i = 0; i < 64; ++i) {
+    EXPECT_FALSE(!absl::MakeInt128(0, uint64_t{1} << i));
+  }
+  for (int i = 0; i < 63; ++i) {
+    EXPECT_FALSE(!absl::MakeInt128(int64_t{1} << i, 0));
+  }
+}
+
+TEST(Int128, AdditionSubtractionTest) {
+  // 64 bit pairs that will not cause overflow / underflow. These test negative
+  // carry; positive carry must be checked separately.
+  std::pair<int64_t, int64_t> cases[]{
+      {0, 0},                              // 0, 0
+      {0, 2945781290834},                  // 0, +
+      {1908357619234, 0},                  // +, 0
+      {0, -1204895918245},                 // 0, -
+      {-2957928523560, 0},                 // -, 0
+      {89023982312461, 98346012567134},    // +, +
+      {-63454234568239, -23456235230773},  // -, -
+      {98263457263502, -21428561935925},   // +, -
+      {-88235237438467, 15923659234573},   // -, +
+  };
+  for (const auto& pair : cases) {
+    SCOPED_TRACE(::testing::Message()
+                 << "pair = {" << pair.first << ", " << pair.second << '}');
+
+    EXPECT_EQ(absl::int128(pair.first + pair.second),
+              absl::int128(pair.first) + absl::int128(pair.second));
+    EXPECT_EQ(absl::int128(pair.second + pair.first),
+              absl::int128(pair.second) += absl::int128(pair.first));
+
+    EXPECT_EQ(absl::int128(pair.first - pair.second),
+              absl::int128(pair.first) - absl::int128(pair.second));
+    EXPECT_EQ(absl::int128(pair.second - pair.first),
+              absl::int128(pair.second) -= absl::int128(pair.first));
+
+    EXPECT_EQ(
+        absl::MakeInt128(pair.second + pair.first, 0),
+        absl::MakeInt128(pair.second, 0) + absl::MakeInt128(pair.first, 0));
+    EXPECT_EQ(
+        absl::MakeInt128(pair.first + pair.second, 0),
+        absl::MakeInt128(pair.first, 0) += absl::MakeInt128(pair.second, 0));
+
+    EXPECT_EQ(
+        absl::MakeInt128(pair.second - pair.first, 0),
+        absl::MakeInt128(pair.second, 0) - absl::MakeInt128(pair.first, 0));
+    EXPECT_EQ(
+        absl::MakeInt128(pair.first - pair.second, 0),
+        absl::MakeInt128(pair.first, 0) -= absl::MakeInt128(pair.second, 0));
+  }
+
+  // check positive carry
+  EXPECT_EQ(absl::MakeInt128(31, 0),
+            absl::MakeInt128(20, 1) +
+                absl::MakeInt128(10, std::numeric_limits<uint64_t>::max()));
+}
+
+TEST(Int128, IncrementDecrementTest) {
+  absl::int128 value = 0;
+  EXPECT_EQ(0, value++);
+  EXPECT_EQ(1, value);
+  EXPECT_EQ(1, value--);
+  EXPECT_EQ(0, value);
+  EXPECT_EQ(-1, --value);
+  EXPECT_EQ(-1, value);
+  EXPECT_EQ(0, ++value);
+  EXPECT_EQ(0, value);
+}
+
+TEST(Int128, MultiplicationTest) {
+  // 1 bit x 1 bit, and negative combinations
+  for (int i = 0; i < 64; ++i) {
+    for (int j = 0; j < 127 - i; ++j) {
+      SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
+      absl::int128 a = absl::int128(1) << i;
+      absl::int128 b = absl::int128(1) << j;
+      absl::int128 c = absl::int128(1) << (i + j);
+
+      EXPECT_EQ(c, a * b);
+      EXPECT_EQ(-c, -a * b);
+      EXPECT_EQ(-c, a * -b);
+      EXPECT_EQ(c, -a * -b);
+
+      EXPECT_EQ(c, absl::int128(a) *= b);
+      EXPECT_EQ(-c, absl::int128(-a) *= b);
+      EXPECT_EQ(-c, absl::int128(a) *= -b);
+      EXPECT_EQ(c, absl::int128(-a) *= -b);
+    }
+  }
+
+  // Pairs of random values that will not overflow signed 64-bit multiplication
+  std::pair<int64_t, int64_t> small_values[] = {
+      {0x5e61, 0xf29f79ca14b4},    // +, +
+      {0x3e033b, -0x612c0ee549},   // +, -
+      {-0x052ce7e8, 0x7c728f0f},   // -, +
+      {-0x3af7054626, -0xfb1e1d},  // -, -
+  };
+  for (const std::pair<int64_t, int64_t>& pair : small_values) {
+    SCOPED_TRACE(::testing::Message()
+                 << "pair = {" << pair.first << ", " << pair.second << '}');
+
+    EXPECT_EQ(absl::int128(pair.first * pair.second),
+              absl::int128(pair.first) * absl::int128(pair.second));
+    EXPECT_EQ(absl::int128(pair.first * pair.second),
+              absl::int128(pair.first) *= absl::int128(pair.second));
+
+    EXPECT_EQ(absl::MakeInt128(pair.first * pair.second, 0),
+              absl::MakeInt128(pair.first, 0) * absl::int128(pair.second));
+    EXPECT_EQ(absl::MakeInt128(pair.first * pair.second, 0),
+              absl::MakeInt128(pair.first, 0) *= absl::int128(pair.second));
+  }
+
+  // Pairs of positive random values that will not overflow 64-bit
+  // multiplication and can be left shifted by 32 without overflow
+  std::pair<int64_t, int64_t> small_values2[] = {
+      {0x1bb0a110, 0x31487671},
+      {0x4792784e, 0x28add7d7},
+      {0x7b66553a, 0x11dff8ef},
+  };
+  for (const std::pair<int64_t, int64_t>& pair : small_values2) {
+    SCOPED_TRACE(::testing::Message()
+                 << "pair = {" << pair.first << ", " << pair.second << '}');
+
+    absl::int128 a = absl::int128(pair.first << 32);
+    absl::int128 b = absl::int128(pair.second << 32);
+    absl::int128 c = absl::MakeInt128(pair.first * pair.second, 0);
+
+    EXPECT_EQ(c, a * b);
+    EXPECT_EQ(-c, -a * b);
+    EXPECT_EQ(-c, a * -b);
+    EXPECT_EQ(c, -a * -b);
+
+    EXPECT_EQ(c, absl::int128(a) *= b);
+    EXPECT_EQ(-c, absl::int128(-a) *= b);
+    EXPECT_EQ(-c, absl::int128(a) *= -b);
+    EXPECT_EQ(c, absl::int128(-a) *= -b);
+  }
+
+  // check 0, 1, and -1 behavior with large values
+  absl::int128 large_values[] = {
+      {absl::MakeInt128(0xd66f061af02d0408, 0x727d2846cb475b53)},
+      {absl::MakeInt128(0x27b8d5ed6104452d, 0x03f8a33b0ee1df4f)},
+      {-absl::MakeInt128(0x621b6626b9e8d042, 0x27311ac99df00938)},
+      {-absl::MakeInt128(0x34e0656f1e95fb60, 0x4281cfd731257a47)},
+  };
+  for (absl::int128 value : large_values) {
+    EXPECT_EQ(0, 0 * value);
+    EXPECT_EQ(0, value * 0);
+    EXPECT_EQ(0, absl::int128(0) *= value);
+    EXPECT_EQ(0, value *= 0);
+
+    EXPECT_EQ(value, 1 * value);
+    EXPECT_EQ(value, value * 1);
+    EXPECT_EQ(value, absl::int128(1) *= value);
+    EXPECT_EQ(value, value *= 1);
+
+    EXPECT_EQ(-value, -1 * value);
+    EXPECT_EQ(-value, value * -1);
+    EXPECT_EQ(-value, absl::int128(-1) *= value);
+    EXPECT_EQ(-value, value *= -1);
+  }
+
+  // Manually calculated random large value cases
+  EXPECT_EQ(absl::MakeInt128(0xcd0efd3442219bb, 0xde47c05bcd9df6e1),
+            absl::MakeInt128(0x7c6448, 0x3bc4285c47a9d253) * 0x1a6037537b);
+  EXPECT_EQ(-absl::MakeInt128(0x1f8f149850b1e5e6, 0x1e50d6b52d272c3e),
+            -absl::MakeInt128(0x23, 0x2e68a513ca1b8859) * 0xe5a434cd14866e);
+  EXPECT_EQ(-absl::MakeInt128(0x55cae732029d1fce, 0xca6474b6423263e4),
+            0xa9b98a8ddf66bc * -absl::MakeInt128(0x81, 0x672e58231e2469d7));
+  EXPECT_EQ(absl::MakeInt128(0x19c8b7620b507dc4, 0xfec042b71a5f29a4),
+            -0x3e39341147 * -absl::MakeInt128(0x6a14b2, 0x5ed34cca42327b3c));
+
+  EXPECT_EQ(absl::MakeInt128(0xcd0efd3442219bb, 0xde47c05bcd9df6e1),
+            absl::MakeInt128(0x7c6448, 0x3bc4285c47a9d253) *= 0x1a6037537b);
+  EXPECT_EQ(-absl::MakeInt128(0x1f8f149850b1e5e6, 0x1e50d6b52d272c3e),
+            -absl::MakeInt128(0x23, 0x2e68a513ca1b8859) *= 0xe5a434cd14866e);
+  EXPECT_EQ(-absl::MakeInt128(0x55cae732029d1fce, 0xca6474b6423263e4),
+            absl::int128(0xa9b98a8ddf66bc) *=
+            -absl::MakeInt128(0x81, 0x672e58231e2469d7));
+  EXPECT_EQ(absl::MakeInt128(0x19c8b7620b507dc4, 0xfec042b71a5f29a4),
+            absl::int128(-0x3e39341147) *=
+            -absl::MakeInt128(0x6a14b2, 0x5ed34cca42327b3c));
+}
+
+TEST(Int128, DivisionAndModuloTest) {
+  // Check against 64 bit division and modulo operators with a sample of
+  // randomly generated pairs.
+  std::pair<int64_t, int64_t> small_pairs[] = {
+      {0x15f2a64138, 0x67da05},    {0x5e56d194af43045f, 0xcf1543fb99},
+      {0x15e61ed052036a, -0xc8e6}, {0x88125a341e85, -0xd23fb77683},
+      {-0xc06e20, 0x5a},           {-0x4f100219aea3e85d, 0xdcc56cb4efe993},
+      {-0x168d629105, -0xa7},      {-0x7b44e92f03ab2375, -0x6516},
+  };
+  for (const std::pair<int64_t, int64_t>& pair : small_pairs) {
+    SCOPED_TRACE(::testing::Message()
+                 << "pair = {" << pair.first << ", " << pair.second << '}');
+
+    absl::int128 dividend = pair.first;
+    absl::int128 divisor = pair.second;
+    int64_t quotient = pair.first / pair.second;
+    int64_t remainder = pair.first % pair.second;
+
+    EXPECT_EQ(quotient, dividend / divisor);
+    EXPECT_EQ(quotient, absl::int128(dividend) /= divisor);
+    EXPECT_EQ(remainder, dividend % divisor);
+    EXPECT_EQ(remainder, absl::int128(dividend) %= divisor);
+  }
+
+  // Test behavior with 0, 1, and -1 with a sample of randomly generated large
+  // values.
+  absl::int128 values[] = {
+      absl::MakeInt128(0x63d26ee688a962b2, 0x9e1411abda5c1d70),
+      absl::MakeInt128(0x152f385159d6f986, 0xbf8d48ef63da395d),
+      -absl::MakeInt128(0x3098d7567030038c, 0x14e7a8a098dc2164),
+      -absl::MakeInt128(0x49a037aca35c809f, 0xa6a87525480ef330),
+  };
+  for (absl::int128 value : values) {
+    SCOPED_TRACE(::testing::Message() << "value = " << value);
+
+    EXPECT_EQ(0, 0 / value);
+    EXPECT_EQ(0, absl::int128(0) /= value);
+    EXPECT_EQ(0, 0 % value);
+    EXPECT_EQ(0, absl::int128(0) %= value);
+
+    EXPECT_EQ(value, value / 1);
+    EXPECT_EQ(value, absl::int128(value) /= 1);
+    EXPECT_EQ(0, value % 1);
+    EXPECT_EQ(0, absl::int128(value) %= 1);
+
+    EXPECT_EQ(-value, value / -1);
+    EXPECT_EQ(-value, absl::int128(value) /= -1);
+    EXPECT_EQ(0, value % -1);
+    EXPECT_EQ(0, absl::int128(value) %= -1);
+  }
+
+  // Min and max values
+  EXPECT_EQ(0, absl::Int128Max() / absl::Int128Min());
+  EXPECT_EQ(absl::Int128Max(), absl::Int128Max() % absl::Int128Min());
+  EXPECT_EQ(-1, absl::Int128Min() / absl::Int128Max());
+  EXPECT_EQ(-1, absl::Int128Min() % absl::Int128Max());
+
+  // Power of two division and modulo of random large dividends
+  absl::int128 positive_values[] = {
+      absl::MakeInt128(0x21e1a1cc69574620, 0xe7ac447fab2fc869),
+      absl::MakeInt128(0x32c2ff3ab89e66e8, 0x03379a613fd1ce74),
+      absl::MakeInt128(0x6f32ca786184dcaf, 0x046f9c9ecb3a9ce1),
+      absl::MakeInt128(0x1aeb469dd990e0ee, 0xda2740f243cd37eb),
+  };
+  for (absl::int128 value : positive_values) {
+    for (int i = 0; i < 127; ++i) {
+      SCOPED_TRACE(::testing::Message()
+                   << "value = " << value << "; i = " << i);
+      absl::int128 power_of_two = absl::int128(1) << i;
+
+      EXPECT_EQ(value >> i, value / power_of_two);
+      EXPECT_EQ(value >> i, absl::int128(value) /= power_of_two);
+      EXPECT_EQ(value & (power_of_two - 1), value % power_of_two);
+      EXPECT_EQ(value & (power_of_two - 1),
+                absl::int128(value) %= power_of_two);
+    }
+  }
+
+  // Manually calculated cases with random large dividends
+  struct DivisionModCase {
+    absl::int128 dividend;
+    absl::int128 divisor;
+    absl::int128 quotient;
+    absl::int128 remainder;
+  };
+  DivisionModCase manual_cases[] = {
+      {absl::MakeInt128(0x6ada48d489007966, 0x3c9c5c98150d5d69),
+       absl::MakeInt128(0x8bc308fb, 0x8cb9cc9a3b803344), 0xc3b87e08,
+       absl::MakeInt128(0x1b7db5e1, 0xd9eca34b7af04b49)},
+      {absl::MakeInt128(0xd6946511b5b, 0x4886c5c96546bf5f),
+       -absl::MakeInt128(0x263b, 0xfd516279efcfe2dc), -0x59cbabf0,
+       absl::MakeInt128(0x622, 0xf462909155651d1f)},
+      {-absl::MakeInt128(0x33db734f9e8d1399, 0x8447ac92482bca4d), 0x37495078240,
+       -absl::MakeInt128(0xf01f1, 0xbc0368bf9a77eae8), -0x21a508f404d},
+      {-absl::MakeInt128(0x13f837b409a07e7d, 0x7fc8e248a7d73560), -0x1b9f,
+       absl::MakeInt128(0xb9157556d724, 0xb14f635714d7563e), -0x1ade},
+  };
+  for (const DivisionModCase test_case : manual_cases) {
+    EXPECT_EQ(test_case.quotient, test_case.dividend / test_case.divisor);
+    EXPECT_EQ(test_case.quotient,
+              absl::int128(test_case.dividend) /= test_case.divisor);
+    EXPECT_EQ(test_case.remainder, test_case.dividend % test_case.divisor);
+    EXPECT_EQ(test_case.remainder,
+              absl::int128(test_case.dividend) %= test_case.divisor);
+  }
+}
+
+TEST(Int128, BitwiseLogicTest) {
+  EXPECT_EQ(absl::int128(-1), ~absl::int128(0));
+
+  absl::int128 values[]{
+      0, -1, 0xde400bee05c3ff6b, absl::MakeInt128(0x7f32178dd81d634a, 0),
+      absl::MakeInt128(0xaf539057055613a9, 0x7d104d7d946c2e4d)};
+  for (absl::int128 value : values) {
+    EXPECT_EQ(value, ~~value);
+
+    EXPECT_EQ(value, value | value);
+    EXPECT_EQ(value, value & value);
+    EXPECT_EQ(0, value ^ value);
+
+    EXPECT_EQ(value, absl::int128(value) |= value);
+    EXPECT_EQ(value, absl::int128(value) &= value);
+    EXPECT_EQ(0, absl::int128(value) ^= value);
+
+    EXPECT_EQ(value, value | 0);
+    EXPECT_EQ(0, value & 0);
+    EXPECT_EQ(value, value ^ 0);
+
+    EXPECT_EQ(absl::int128(-1), value | absl::int128(-1));
+    EXPECT_EQ(value, value & absl::int128(-1));
+    EXPECT_EQ(~value, value ^ absl::int128(-1));
+  }
+
+  // small sample of randomly generated int64_t's
+  std::pair<int64_t, int64_t> pairs64[]{
+      {0x7f86797f5e991af4, 0x1ee30494fb007c97},
+      {0x0b278282bacf01af, 0x58780e0a57a49e86},
+      {0x059f266ccb93a666, 0x3d5b731bae9286f5},
+      {0x63c0c4820f12108c, 0x58166713c12e1c3a},
+      {0x381488bb2ed2a66e, 0x2220a3eb76a3698c},
+      {0x2a0a0dfb81e06f21, 0x4b60585927f5523c},
+      {0x555b1c3a03698537, 0x25478cd19d8e53cb},
+      {0x4750f6f27d779225, 0x16397553c6ff05fc},
+  };
+  for (const std::pair<int64_t, int64_t>& pair : pairs64) {
+    SCOPED_TRACE(::testing::Message()
+                 << "pair = {" << pair.first << ", " << pair.second << '}');
+
+    EXPECT_EQ(absl::MakeInt128(~pair.first, ~pair.second),
+              ~absl::MakeInt128(pair.first, pair.second));
+
+    EXPECT_EQ(absl::int128(pair.first & pair.second),
+              absl::int128(pair.first) & absl::int128(pair.second));
+    EXPECT_EQ(absl::int128(pair.first | pair.second),
+              absl::int128(pair.first) | absl::int128(pair.second));
+    EXPECT_EQ(absl::int128(pair.first ^ pair.second),
+              absl::int128(pair.first) ^ absl::int128(pair.second));
+
+    EXPECT_EQ(absl::int128(pair.first & pair.second),
+              absl::int128(pair.first) &= absl::int128(pair.second));
+    EXPECT_EQ(absl::int128(pair.first | pair.second),
+              absl::int128(pair.first) |= absl::int128(pair.second));
+    EXPECT_EQ(absl::int128(pair.first ^ pair.second),
+              absl::int128(pair.first) ^= absl::int128(pair.second));
+
+    EXPECT_EQ(
+        absl::MakeInt128(pair.first & pair.second, 0),
+        absl::MakeInt128(pair.first, 0) & absl::MakeInt128(pair.second, 0));
+    EXPECT_EQ(
+        absl::MakeInt128(pair.first | pair.second, 0),
+        absl::MakeInt128(pair.first, 0) | absl::MakeInt128(pair.second, 0));
+    EXPECT_EQ(
+        absl::MakeInt128(pair.first ^ pair.second, 0),
+        absl::MakeInt128(pair.first, 0) ^ absl::MakeInt128(pair.second, 0));
+
+    EXPECT_EQ(
+        absl::MakeInt128(pair.first & pair.second, 0),
+        absl::MakeInt128(pair.first, 0) &= absl::MakeInt128(pair.second, 0));
+    EXPECT_EQ(
+        absl::MakeInt128(pair.first | pair.second, 0),
+        absl::MakeInt128(pair.first, 0) |= absl::MakeInt128(pair.second, 0));
+    EXPECT_EQ(
+        absl::MakeInt128(pair.first ^ pair.second, 0),
+        absl::MakeInt128(pair.first, 0) ^= absl::MakeInt128(pair.second, 0));
+  }
+}
+
+TEST(Int128, BitwiseShiftTest) {
+  for (int i = 0; i < 64; ++i) {
+    for (int j = 0; j <= i; ++j) {
+      // Left shift from j-th bit to i-th bit.
+      SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
+      EXPECT_EQ(uint64_t{1} << i, absl::int128(uint64_t{1} << j) << (i - j));
+      EXPECT_EQ(uint64_t{1} << i, absl::int128(uint64_t{1} << j) <<= (i - j));
+    }
+  }
+  for (int i = 0; i < 63; ++i) {
+    for (int j = 0; j < 64; ++j) {
+      // Left shift from j-th bit to (i + 64)-th bit.
+      SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
+      EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
+                absl::int128(uint64_t{1} << j) << (i + 64 - j));
+      EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
+                absl::int128(uint64_t{1} << j) <<= (i + 64 - j));
+    }
+    for (int j = 0; j <= i; ++j) {
+      // Left shift from (j + 64)-th bit to (i + 64)-th bit.
+      SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
+      EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
+                absl::MakeInt128(uint64_t{1} << j, 0) << (i - j));
+      EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
+                absl::MakeInt128(uint64_t{1} << j, 0) <<= (i - j));
+    }
+  }
+
+  for (int i = 0; i < 64; ++i) {
+    for (int j = i; j < 64; ++j) {
+      // Right shift from j-th bit to i-th bit.
+      SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
+      EXPECT_EQ(uint64_t{1} << i, absl::int128(uint64_t{1} << j) >> (j - i));
+      EXPECT_EQ(uint64_t{1} << i, absl::int128(uint64_t{1} << j) >>= (j - i));
+    }
+    for (int j = 0; j < 63; ++j) {
+      // Right shift from (j + 64)-th bit to i-th bit.
+      SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
+      EXPECT_EQ(uint64_t{1} << i,
+                absl::MakeInt128(uint64_t{1} << j, 0) >> (j + 64 - i));
+      EXPECT_EQ(uint64_t{1} << i,
+                absl::MakeInt128(uint64_t{1} << j, 0) >>= (j + 64 - i));
+    }
+  }
+  for (int i = 0; i < 63; ++i) {
+    for (int j = i; j < 63; ++j) {
+      // Right shift from (j + 64)-th bit to (i + 64)-th bit.
+      SCOPED_TRACE(::testing::Message() << "i = " << i << "; j = " << j);
+      EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
+                absl::MakeInt128(uint64_t{1} << j, 0) >> (j - i));
+      EXPECT_EQ(absl::MakeInt128(uint64_t{1} << i, 0),
+                absl::MakeInt128(uint64_t{1} << j, 0) >>= (j - i));
+    }
+  }
+}
+
+TEST(Int128, NumericLimitsTest) {
+  static_assert(std::numeric_limits<absl::int128>::is_specialized, "");
+  static_assert(std::numeric_limits<absl::int128>::is_signed, "");
+  static_assert(std::numeric_limits<absl::int128>::is_integer, "");
+  EXPECT_EQ(static_cast<int>(127 * std::log10(2)),
+            std::numeric_limits<absl::int128>::digits10);
+  EXPECT_EQ(absl::Int128Min(), std::numeric_limits<absl::int128>::min());
+  EXPECT_EQ(absl::Int128Min(), std::numeric_limits<absl::int128>::lowest());
+  EXPECT_EQ(absl::Int128Max(), std::numeric_limits<absl::int128>::max());
+}
+
 }  // namespace