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-rw-r--r--third_party/abseil_cpp/absl/random/internal/generate_real_test.cc497
1 files changed, 0 insertions, 497 deletions
diff --git a/third_party/abseil_cpp/absl/random/internal/generate_real_test.cc b/third_party/abseil_cpp/absl/random/internal/generate_real_test.cc
deleted file mode 100644
index aa02f0c2c1..0000000000
--- a/third_party/abseil_cpp/absl/random/internal/generate_real_test.cc
+++ /dev/null
@@ -1,497 +0,0 @@
-// 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.
-
-#include "absl/random/internal/generate_real.h"
-
-#include <cfloat>
-#include <cstddef>
-#include <cstdint>
-#include <string>
-
-#include "gtest/gtest.h"
-#include "absl/base/internal/bits.h"
-#include "absl/flags/flag.h"
-
-ABSL_FLAG(int64_t, absl_random_test_trials, 50000,
-          "Number of trials for the probability tests.");
-
-using absl::random_internal::GenerateNegativeTag;
-using absl::random_internal::GeneratePositiveTag;
-using absl::random_internal::GenerateRealFromBits;
-using absl::random_internal::GenerateSignedTag;
-
-namespace {
-
-TEST(GenerateRealTest, U64ToFloat_Positive_NoZero_Test) {
-  auto ToFloat = [](uint64_t a) {
-    return GenerateRealFromBits<float, GeneratePositiveTag, false>(a);
-  };
-  EXPECT_EQ(ToFloat(0x0000000000000000), 2.710505431e-20f);
-  EXPECT_EQ(ToFloat(0x0000000000000001), 5.421010862e-20f);
-  EXPECT_EQ(ToFloat(0x8000000000000000), 0.5);
-  EXPECT_EQ(ToFloat(0x8000000000000001), 0.5);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), 0.9999999404f);
-}
-
-TEST(GenerateRealTest, U64ToFloat_Positive_Zero_Test) {
-  auto ToFloat = [](uint64_t a) {
-    return GenerateRealFromBits<float, GeneratePositiveTag, true>(a);
-  };
-  EXPECT_EQ(ToFloat(0x0000000000000000), 0.0);
-  EXPECT_EQ(ToFloat(0x0000000000000001), 5.421010862e-20f);
-  EXPECT_EQ(ToFloat(0x8000000000000000), 0.5);
-  EXPECT_EQ(ToFloat(0x8000000000000001), 0.5);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), 0.9999999404f);
-}
-
-TEST(GenerateRealTest, U64ToFloat_Negative_NoZero_Test) {
-  auto ToFloat = [](uint64_t a) {
-    return GenerateRealFromBits<float, GenerateNegativeTag, false>(a);
-  };
-  EXPECT_EQ(ToFloat(0x0000000000000000), -2.710505431e-20f);
-  EXPECT_EQ(ToFloat(0x0000000000000001), -5.421010862e-20f);
-  EXPECT_EQ(ToFloat(0x8000000000000000), -0.5);
-  EXPECT_EQ(ToFloat(0x8000000000000001), -0.5);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), -0.9999999404f);
-}
-
-TEST(GenerateRealTest, U64ToFloat_Negative_Zero_Test) {
-  auto ToFloat = [](uint64_t a) {
-    return GenerateRealFromBits<float, GenerateNegativeTag, true>(a);
-  };
-  EXPECT_EQ(ToFloat(0x0000000000000000), 0.0);
-  EXPECT_EQ(ToFloat(0x0000000000000001), -5.421010862e-20f);
-  EXPECT_EQ(ToFloat(0x8000000000000000), -0.5);
-  EXPECT_EQ(ToFloat(0x8000000000000001), -0.5);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), -0.9999999404f);
-}
-
-TEST(GenerateRealTest, U64ToFloat_Signed_NoZero_Test) {
-  auto ToFloat = [](uint64_t a) {
-    return GenerateRealFromBits<float, GenerateSignedTag, false>(a);
-  };
-  EXPECT_EQ(ToFloat(0x0000000000000000), 5.421010862e-20f);
-  EXPECT_EQ(ToFloat(0x0000000000000001), 1.084202172e-19f);
-  EXPECT_EQ(ToFloat(0x7FFFFFFFFFFFFFFF), 0.9999999404f);
-  EXPECT_EQ(ToFloat(0x8000000000000000), -5.421010862e-20f);
-  EXPECT_EQ(ToFloat(0x8000000000000001), -1.084202172e-19f);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), -0.9999999404f);
-}
-
-TEST(GenerateRealTest, U64ToFloat_Signed_Zero_Test) {
-  auto ToFloat = [](uint64_t a) {
-    return GenerateRealFromBits<float, GenerateSignedTag, true>(a);
-  };
-  EXPECT_EQ(ToFloat(0x0000000000000000), 0);
-  EXPECT_EQ(ToFloat(0x0000000000000001), 1.084202172e-19f);
-  EXPECT_EQ(ToFloat(0x7FFFFFFFFFFFFFFF), 0.9999999404f);
-  EXPECT_EQ(ToFloat(0x8000000000000000), 0);
-  EXPECT_EQ(ToFloat(0x8000000000000001), -1.084202172e-19f);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), -0.9999999404f);
-}
-
-TEST(GenerateRealTest, U64ToFloat_Signed_Bias_Test) {
-  auto ToFloat = [](uint64_t a) {
-    return GenerateRealFromBits<float, GenerateSignedTag, true>(a, 1);
-  };
-  EXPECT_EQ(ToFloat(0x0000000000000000), 0);
-  EXPECT_EQ(ToFloat(0x0000000000000001), 2 * 1.084202172e-19f);
-  EXPECT_EQ(ToFloat(0x7FFFFFFFFFFFFFFF), 2 * 0.9999999404f);
-  EXPECT_EQ(ToFloat(0x8000000000000000), 0);
-  EXPECT_EQ(ToFloat(0x8000000000000001), 2 * -1.084202172e-19f);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), 2 * -0.9999999404f);
-}
-
-TEST(GenerateRealTest, U64ToFloatTest) {
-  auto ToFloat = [](uint64_t a) -> float {
-    return GenerateRealFromBits<float, GeneratePositiveTag, true>(a);
-  };
-
-  EXPECT_EQ(ToFloat(0x0000000000000000), 0.0f);
-
-  EXPECT_EQ(ToFloat(0x8000000000000000), 0.5f);
-  EXPECT_EQ(ToFloat(0x8000000000000001), 0.5f);
-  EXPECT_EQ(ToFloat(0x800000FFFFFFFFFF), 0.5f);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), 0.9999999404f);
-
-  EXPECT_GT(ToFloat(0x0000000000000001), 0.0f);
-
-  EXPECT_NE(ToFloat(0x7FFFFF0000000000), ToFloat(0x7FFFFEFFFFFFFFFF));
-
-  EXPECT_LT(ToFloat(0xFFFFFFFFFFFFFFFF), 1.0f);
-  int32_t two_to_24 = 1 << 24;
-  EXPECT_EQ(static_cast<int32_t>(ToFloat(0xFFFFFFFFFFFFFFFF) * two_to_24),
-            two_to_24 - 1);
-  EXPECT_NE(static_cast<int32_t>(ToFloat(0xFFFFFFFFFFFFFFFF) * two_to_24 * 2),
-            two_to_24 * 2 - 1);
-  EXPECT_EQ(ToFloat(0xFFFFFFFFFFFFFFFF), ToFloat(0xFFFFFF0000000000));
-  EXPECT_NE(ToFloat(0xFFFFFFFFFFFFFFFF), ToFloat(0xFFFFFEFFFFFFFFFF));
-  EXPECT_EQ(ToFloat(0x7FFFFFFFFFFFFFFF), ToFloat(0x7FFFFF8000000000));
-  EXPECT_NE(ToFloat(0x7FFFFFFFFFFFFFFF), ToFloat(0x7FFFFF7FFFFFFFFF));
-  EXPECT_EQ(ToFloat(0x3FFFFFFFFFFFFFFF), ToFloat(0x3FFFFFC000000000));
-  EXPECT_NE(ToFloat(0x3FFFFFFFFFFFFFFF), ToFloat(0x3FFFFFBFFFFFFFFF));
-
-  // For values where every bit counts, the values scale as multiples of the
-  // input.
-  for (int i = 0; i < 100; ++i) {
-    EXPECT_EQ(i * ToFloat(0x0000000000000001), ToFloat(i));
-  }
-
-  // For each i: value generated from (1 << i).
-  float exp_values[64];
-  exp_values[63] = 0.5f;
-  for (int i = 62; i >= 0; --i) exp_values[i] = 0.5f * exp_values[i + 1];
-  constexpr uint64_t one = 1;
-  for (int i = 0; i < 64; ++i) {
-    EXPECT_EQ(ToFloat(one << i), exp_values[i]);
-    for (int j = 1; j < FLT_MANT_DIG && i - j >= 0; ++j) {
-      EXPECT_NE(exp_values[i] + exp_values[i - j], exp_values[i]);
-      EXPECT_EQ(ToFloat((one << i) + (one << (i - j))),
-                exp_values[i] + exp_values[i - j]);
-    }
-    for (int j = FLT_MANT_DIG; i - j >= 0; ++j) {
-      EXPECT_EQ(exp_values[i] + exp_values[i - j], exp_values[i]);
-      EXPECT_EQ(ToFloat((one << i) + (one << (i - j))), exp_values[i]);
-    }
-  }
-}
-
-TEST(GenerateRealTest, U64ToDouble_Positive_NoZero_Test) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GeneratePositiveTag, false>(a);
-  };
-
-  EXPECT_EQ(ToDouble(0x0000000000000000), 2.710505431213761085e-20);
-  EXPECT_EQ(ToDouble(0x0000000000000001), 5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x0000000000000002), 1.084202172485504434e-19);
-  EXPECT_EQ(ToDouble(0x8000000000000000), 0.5);
-  EXPECT_EQ(ToDouble(0x8000000000000001), 0.5);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), 0.999999999999999888978);
-}
-
-TEST(GenerateRealTest, U64ToDouble_Positive_Zero_Test) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GeneratePositiveTag, true>(a);
-  };
-
-  EXPECT_EQ(ToDouble(0x0000000000000000), 0.0);
-  EXPECT_EQ(ToDouble(0x0000000000000001), 5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x8000000000000000), 0.5);
-  EXPECT_EQ(ToDouble(0x8000000000000001), 0.5);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), 0.999999999999999888978);
-}
-
-TEST(GenerateRealTest, U64ToDouble_Negative_NoZero_Test) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GenerateNegativeTag, false>(a);
-  };
-
-  EXPECT_EQ(ToDouble(0x0000000000000000), -2.710505431213761085e-20);
-  EXPECT_EQ(ToDouble(0x0000000000000001), -5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x0000000000000002), -1.084202172485504434e-19);
-  EXPECT_EQ(ToDouble(0x8000000000000000), -0.5);
-  EXPECT_EQ(ToDouble(0x8000000000000001), -0.5);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), -0.999999999999999888978);
-}
-
-TEST(GenerateRealTest, U64ToDouble_Negative_Zero_Test) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GenerateNegativeTag, true>(a);
-  };
-
-  EXPECT_EQ(ToDouble(0x0000000000000000), 0.0);
-  EXPECT_EQ(ToDouble(0x0000000000000001), -5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x0000000000000002), -1.084202172485504434e-19);
-  EXPECT_EQ(ToDouble(0x8000000000000000), -0.5);
-  EXPECT_EQ(ToDouble(0x8000000000000001), -0.5);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), -0.999999999999999888978);
-}
-
-TEST(GenerateRealTest, U64ToDouble_Signed_NoZero_Test) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GenerateSignedTag, false>(a);
-  };
-
-  EXPECT_EQ(ToDouble(0x0000000000000000), 5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x0000000000000001), 1.084202172485504434e-19);
-  EXPECT_EQ(ToDouble(0x7FFFFFFFFFFFFFFF), 0.999999999999999888978);
-  EXPECT_EQ(ToDouble(0x8000000000000000), -5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x8000000000000001), -1.084202172485504434e-19);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), -0.999999999999999888978);
-}
-
-TEST(GenerateRealTest, U64ToDouble_Signed_Zero_Test) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GenerateSignedTag, true>(a);
-  };
-  EXPECT_EQ(ToDouble(0x0000000000000000), 0);
-  EXPECT_EQ(ToDouble(0x0000000000000001), 1.084202172485504434e-19);
-  EXPECT_EQ(ToDouble(0x7FFFFFFFFFFFFFFF), 0.999999999999999888978);
-  EXPECT_EQ(ToDouble(0x8000000000000000), 0);
-  EXPECT_EQ(ToDouble(0x8000000000000001), -1.084202172485504434e-19);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), -0.999999999999999888978);
-}
-
-TEST(GenerateRealTest, U64ToDouble_GenerateSignedTag_Bias_Test) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GenerateSignedTag, true>(a, -1);
-  };
-  EXPECT_EQ(ToDouble(0x0000000000000000), 0);
-  EXPECT_EQ(ToDouble(0x0000000000000001), 1.084202172485504434e-19 / 2);
-  EXPECT_EQ(ToDouble(0x7FFFFFFFFFFFFFFF), 0.999999999999999888978 / 2);
-  EXPECT_EQ(ToDouble(0x8000000000000000), 0);
-  EXPECT_EQ(ToDouble(0x8000000000000001), -1.084202172485504434e-19 / 2);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), -0.999999999999999888978 / 2);
-}
-
-TEST(GenerateRealTest, U64ToDoubleTest) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GeneratePositiveTag, true>(a);
-  };
-
-  EXPECT_EQ(ToDouble(0x0000000000000000), 0.0);
-  EXPECT_EQ(ToDouble(0x0000000000000000), 0.0);
-
-  EXPECT_EQ(ToDouble(0x0000000000000001), 5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x7fffffffffffffef), 0.499999999999999944489);
-  EXPECT_EQ(ToDouble(0x8000000000000000), 0.5);
-
-  // For values > 0.5, RandU64ToDouble discards up to 11 bits. (64-53).
-  EXPECT_EQ(ToDouble(0x8000000000000001), 0.5);
-  EXPECT_EQ(ToDouble(0x80000000000007FF), 0.5);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), 0.999999999999999888978);
-  EXPECT_NE(ToDouble(0x7FFFFFFFFFFFF800), ToDouble(0x7FFFFFFFFFFFF7FF));
-
-  EXPECT_LT(ToDouble(0xFFFFFFFFFFFFFFFF), 1.0);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFF), ToDouble(0xFFFFFFFFFFFFF800));
-  EXPECT_NE(ToDouble(0xFFFFFFFFFFFFFFFF), ToDouble(0xFFFFFFFFFFFFF7FF));
-  EXPECT_EQ(ToDouble(0x7FFFFFFFFFFFFFFF), ToDouble(0x7FFFFFFFFFFFFC00));
-  EXPECT_NE(ToDouble(0x7FFFFFFFFFFFFFFF), ToDouble(0x7FFFFFFFFFFFFBFF));
-  EXPECT_EQ(ToDouble(0x3FFFFFFFFFFFFFFF), ToDouble(0x3FFFFFFFFFFFFE00));
-  EXPECT_NE(ToDouble(0x3FFFFFFFFFFFFFFF), ToDouble(0x3FFFFFFFFFFFFDFF));
-
-  EXPECT_EQ(ToDouble(0x1000000000000001), 0.0625);
-  EXPECT_EQ(ToDouble(0x2000000000000001), 0.125);
-  EXPECT_EQ(ToDouble(0x3000000000000001), 0.1875);
-  EXPECT_EQ(ToDouble(0x4000000000000001), 0.25);
-  EXPECT_EQ(ToDouble(0x5000000000000001), 0.3125);
-  EXPECT_EQ(ToDouble(0x6000000000000001), 0.375);
-  EXPECT_EQ(ToDouble(0x7000000000000001), 0.4375);
-  EXPECT_EQ(ToDouble(0x8000000000000001), 0.5);
-  EXPECT_EQ(ToDouble(0x9000000000000001), 0.5625);
-  EXPECT_EQ(ToDouble(0xa000000000000001), 0.625);
-  EXPECT_EQ(ToDouble(0xb000000000000001), 0.6875);
-  EXPECT_EQ(ToDouble(0xc000000000000001), 0.75);
-  EXPECT_EQ(ToDouble(0xd000000000000001), 0.8125);
-  EXPECT_EQ(ToDouble(0xe000000000000001), 0.875);
-  EXPECT_EQ(ToDouble(0xf000000000000001), 0.9375);
-
-  // Large powers of 2.
-  int64_t two_to_53 = int64_t{1} << 53;
-  EXPECT_EQ(static_cast<int64_t>(ToDouble(0xFFFFFFFFFFFFFFFF) * two_to_53),
-            two_to_53 - 1);
-  EXPECT_NE(static_cast<int64_t>(ToDouble(0xFFFFFFFFFFFFFFFF) * two_to_53 * 2),
-            two_to_53 * 2 - 1);
-
-  // For values where every bit counts, the values scale as multiples of the
-  // input.
-  for (int i = 0; i < 100; ++i) {
-    EXPECT_EQ(i * ToDouble(0x0000000000000001), ToDouble(i));
-  }
-
-  // For each i: value generated from (1 << i).
-  double exp_values[64];
-  exp_values[63] = 0.5;
-  for (int i = 62; i >= 0; --i) exp_values[i] = 0.5 * exp_values[i + 1];
-  constexpr uint64_t one = 1;
-  for (int i = 0; i < 64; ++i) {
-    EXPECT_EQ(ToDouble(one << i), exp_values[i]);
-    for (int j = 1; j < DBL_MANT_DIG && i - j >= 0; ++j) {
-      EXPECT_NE(exp_values[i] + exp_values[i - j], exp_values[i]);
-      EXPECT_EQ(ToDouble((one << i) + (one << (i - j))),
-                exp_values[i] + exp_values[i - j]);
-    }
-    for (int j = DBL_MANT_DIG; i - j >= 0; ++j) {
-      EXPECT_EQ(exp_values[i] + exp_values[i - j], exp_values[i]);
-      EXPECT_EQ(ToDouble((one << i) + (one << (i - j))), exp_values[i]);
-    }
-  }
-}
-
-TEST(GenerateRealTest, U64ToDoubleSignedTest) {
-  auto ToDouble = [](uint64_t a) {
-    return GenerateRealFromBits<double, GenerateSignedTag, false>(a);
-  };
-
-  EXPECT_EQ(ToDouble(0x0000000000000000), 5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x0000000000000001), 1.084202172485504434e-19);
-
-  EXPECT_EQ(ToDouble(0x8000000000000000), -5.42101086242752217004e-20);
-  EXPECT_EQ(ToDouble(0x8000000000000001), -1.084202172485504434e-19);
-
-  const double e_plus = ToDouble(0x0000000000000001);
-  const double e_minus = ToDouble(0x8000000000000001);
-  EXPECT_EQ(e_plus, 1.084202172485504434e-19);
-  EXPECT_EQ(e_minus, -1.084202172485504434e-19);
-
-  EXPECT_EQ(ToDouble(0x3fffffffffffffef), 0.499999999999999944489);
-  EXPECT_EQ(ToDouble(0xbfffffffffffffef), -0.499999999999999944489);
-
-  // For values > 0.5, RandU64ToDouble discards up to 10 bits. (63-53).
-  EXPECT_EQ(ToDouble(0x4000000000000000), 0.5);
-  EXPECT_EQ(ToDouble(0x4000000000000001), 0.5);
-  EXPECT_EQ(ToDouble(0x40000000000003FF), 0.5);
-
-  EXPECT_EQ(ToDouble(0xC000000000000000), -0.5);
-  EXPECT_EQ(ToDouble(0xC000000000000001), -0.5);
-  EXPECT_EQ(ToDouble(0xC0000000000003FF), -0.5);
-
-  EXPECT_EQ(ToDouble(0x7FFFFFFFFFFFFFFe), 0.999999999999999888978);
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFe), -0.999999999999999888978);
-
-  EXPECT_NE(ToDouble(0x7FFFFFFFFFFFF800), ToDouble(0x7FFFFFFFFFFFF7FF));
-
-  EXPECT_LT(ToDouble(0x7FFFFFFFFFFFFFFF), 1.0);
-  EXPECT_GT(ToDouble(0x7FFFFFFFFFFFFFFF), 0.9999999999);
-
-  EXPECT_GT(ToDouble(0xFFFFFFFFFFFFFFFe), -1.0);
-  EXPECT_LT(ToDouble(0xFFFFFFFFFFFFFFFe), -0.999999999);
-
-  EXPECT_EQ(ToDouble(0xFFFFFFFFFFFFFFFe), ToDouble(0xFFFFFFFFFFFFFC00));
-  EXPECT_EQ(ToDouble(0x7FFFFFFFFFFFFFFF), ToDouble(0x7FFFFFFFFFFFFC00));
-  EXPECT_NE(ToDouble(0xFFFFFFFFFFFFFFFe), ToDouble(0xFFFFFFFFFFFFF3FF));
-  EXPECT_NE(ToDouble(0x7FFFFFFFFFFFFFFF), ToDouble(0x7FFFFFFFFFFFF3FF));
-
-  EXPECT_EQ(ToDouble(0x1000000000000001), 0.125);
-  EXPECT_EQ(ToDouble(0x2000000000000001), 0.25);
-  EXPECT_EQ(ToDouble(0x3000000000000001), 0.375);
-  EXPECT_EQ(ToDouble(0x4000000000000001), 0.5);
-  EXPECT_EQ(ToDouble(0x5000000000000001), 0.625);
-  EXPECT_EQ(ToDouble(0x6000000000000001), 0.75);
-  EXPECT_EQ(ToDouble(0x7000000000000001), 0.875);
-  EXPECT_EQ(ToDouble(0x7800000000000001), 0.9375);
-  EXPECT_EQ(ToDouble(0x7c00000000000001), 0.96875);
-  EXPECT_EQ(ToDouble(0x7e00000000000001), 0.984375);
-  EXPECT_EQ(ToDouble(0x7f00000000000001), 0.9921875);
-
-  // 0x8000000000000000 ~= 0
-  EXPECT_EQ(ToDouble(0x9000000000000001), -0.125);
-  EXPECT_EQ(ToDouble(0xa000000000000001), -0.25);
-  EXPECT_EQ(ToDouble(0xb000000000000001), -0.375);
-  EXPECT_EQ(ToDouble(0xc000000000000001), -0.5);
-  EXPECT_EQ(ToDouble(0xd000000000000001), -0.625);
-  EXPECT_EQ(ToDouble(0xe000000000000001), -0.75);
-  EXPECT_EQ(ToDouble(0xf000000000000001), -0.875);
-
-  // Large powers of 2.
-  int64_t two_to_53 = int64_t{1} << 53;
-  EXPECT_EQ(static_cast<int64_t>(ToDouble(0x7FFFFFFFFFFFFFFF) * two_to_53),
-            two_to_53 - 1);
-  EXPECT_EQ(static_cast<int64_t>(ToDouble(0xFFFFFFFFFFFFFFFF) * two_to_53),
-            -(two_to_53 - 1));
-
-  EXPECT_NE(static_cast<int64_t>(ToDouble(0x7FFFFFFFFFFFFFFF) * two_to_53 * 2),
-            two_to_53 * 2 - 1);
-
-  // For values where every bit counts, the values scale as multiples of the
-  // input.
-  for (int i = 1; i < 100; ++i) {
-    EXPECT_EQ(i * e_plus, ToDouble(i)) << i;
-    EXPECT_EQ(i * e_minus, ToDouble(0x8000000000000000 | i)) << i;
-  }
-}
-
-TEST(GenerateRealTest, ExhaustiveFloat) {
-  using absl::base_internal::CountLeadingZeros64;
-  auto ToFloat = [](uint64_t a) {
-    return GenerateRealFromBits<float, GeneratePositiveTag, true>(a);
-  };
-
-  // Rely on RandU64ToFloat generating values from greatest to least when
-  // supplied with uint64_t values from greatest (0xfff...) to least (0x0).  Thus,
-  // this algorithm stores the previous value, and if the new value is at
-  // greater than or equal to the previous value, then there is a collision in
-  // the generation algorithm.
-  //
-  // Use the computation below to convert the random value into a result:
-  //   double res = a() * (1.0f - sample) + b() * sample;
-  float last_f = 1.0, last_g = 2.0;
-  uint64_t f_collisions = 0, g_collisions = 0;
-  uint64_t f_unique = 0, g_unique = 0;
-  uint64_t total = 0;
-  auto count = [&](const float r) {
-    total++;
-    // `f` is mapped to the range [0, 1) (default)
-    const float f = 0.0f * (1.0f - r) + 1.0f * r;
-    if (f >= last_f) {
-      f_collisions++;
-    } else {
-      f_unique++;
-      last_f = f;
-    }
-    // `g` is mapped to the range [1, 2)
-    const float g = 1.0f * (1.0f - r) + 2.0f * r;
-    if (g >= last_g) {
-      g_collisions++;
-    } else {
-      g_unique++;
-      last_g = g;
-    }
-  };
-
-  size_t limit = absl::GetFlag(FLAGS_absl_random_test_trials);
-
-  // Generate all uint64_t which have unique floating point values.
-  // Counting down from 0xFFFFFFFFFFFFFFFFu ... 0x0u
-  uint64_t x = ~uint64_t(0);
-  for (; x != 0 && limit > 0;) {
-    constexpr int kDig = (64 - FLT_MANT_DIG);
-    // Set a decrement value & the next point at which to change
-    // the decrement value. By default these are 1, 0.
-    uint64_t dec = 1;
-    uint64_t chk = 0;
-
-    // Adjust decrement and check value based on how many leading 0
-    // bits are set in the current value.
-    const int clz = CountLeadingZeros64(x);
-    if (clz < kDig) {
-      dec <<= (kDig - clz);
-      chk = (~uint64_t(0)) >> (clz + 1);
-    }
-    for (; x > chk && limit > 0; x -= dec) {
-      count(ToFloat(x));
-      --limit;
-    }
-  }
-
-  static_assert(FLT_MANT_DIG == 24,
-                "The float type is expected to have a 24 bit mantissa.");
-
-  if (limit != 0) {
-    // There are between 2^28 and 2^29 unique values in the range [0, 1).  For
-    // the low values of x, there are 2^24 -1 unique values.  Once x > 2^24,
-    // there are 40 * 2^24 unique values. Thus:
-    // (2 + 4 + 8 ... + 2^23) + 40 * 2^23
-    EXPECT_LT(1 << 28, f_unique);
-    EXPECT_EQ((1 << 24) + 40 * (1 << 23) - 1, f_unique);
-    EXPECT_EQ(total, f_unique);
-    EXPECT_EQ(0, f_collisions);
-
-    // Expect at least 2^23 unique values for the range [1, 2)
-    EXPECT_LE(1 << 23, g_unique);
-    EXPECT_EQ(total - g_unique, g_collisions);
-  }
-}
-
-}  // namespace