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Diffstat (limited to 'third_party/abseil_cpp/absl/random/internal/pool_urbg_test.cc')
| -rw-r--r-- | third_party/abseil_cpp/absl/random/internal/pool_urbg_test.cc | 182 |
1 files changed, 0 insertions, 182 deletions
diff --git a/third_party/abseil_cpp/absl/random/internal/pool_urbg_test.cc b/third_party/abseil_cpp/absl/random/internal/pool_urbg_test.cc deleted file mode 100644 index 53f4eacf16..0000000000 --- a/third_party/abseil_cpp/absl/random/internal/pool_urbg_test.cc +++ /dev/null @@ -1,182 +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/pool_urbg.h" - -#include <algorithm> -#include <bitset> -#include <cmath> -#include <cstdint> -#include <iterator> - -#include "gtest/gtest.h" -#include "absl/meta/type_traits.h" -#include "absl/types/span.h" - -using absl::random_internal::PoolURBG; -using absl::random_internal::RandenPool; - -namespace { - -// is_randen_pool trait is true when parameterized by an RandenPool -template <typename T> -using is_randen_pool = typename absl::disjunction< // - std::is_same<T, RandenPool<uint8_t>>, // - std::is_same<T, RandenPool<uint16_t>>, // - std::is_same<T, RandenPool<uint32_t>>, // - std::is_same<T, RandenPool<uint64_t>>>; // - -// MyFill either calls RandenPool::Fill() or std::generate(..., rng) -template <typename T, typename V> -typename absl::enable_if_t<absl::negation<is_randen_pool<T>>::value, void> // -MyFill(T& rng, absl::Span<V> data) { // NOLINT(runtime/references) - std::generate(std::begin(data), std::end(data), rng); -} - -template <typename T, typename V> -typename absl::enable_if_t<is_randen_pool<T>::value, void> // -MyFill(T& rng, absl::Span<V> data) { // NOLINT(runtime/references) - rng.Fill(data); -} - -template <typename EngineType> -class PoolURBGTypedTest : public ::testing::Test {}; - -using EngineTypes = ::testing::Types< // - RandenPool<uint8_t>, // - RandenPool<uint16_t>, // - RandenPool<uint32_t>, // - RandenPool<uint64_t>, // - PoolURBG<uint8_t, 2>, // - PoolURBG<uint16_t, 2>, // - PoolURBG<uint32_t, 2>, // - PoolURBG<uint64_t, 2>, // - PoolURBG<unsigned int, 8>, // NOLINT(runtime/int) - PoolURBG<unsigned long, 8>, // NOLINT(runtime/int) - PoolURBG<unsigned long int, 4>, // NOLINT(runtime/int) - PoolURBG<unsigned long long, 4>>; // NOLINT(runtime/int) - -TYPED_TEST_SUITE(PoolURBGTypedTest, EngineTypes); - -// This test is checks that the engines meet the URBG interface requirements -// defined in [rand.req.urbg]. -TYPED_TEST(PoolURBGTypedTest, URBGInterface) { - using E = TypeParam; - using T = typename E::result_type; - - static_assert(std::is_copy_constructible<E>::value, - "engine must be copy constructible"); - - static_assert(absl::is_copy_assignable<E>::value, - "engine must be copy assignable"); - - E e; - const E x; - - e(); - - static_assert(std::is_same<decltype(e()), T>::value, - "return type of operator() must be result_type"); - - E u0(x); - u0(); - - E u1 = e; - u1(); -} - -// This validates that sequences are independent. -TYPED_TEST(PoolURBGTypedTest, VerifySequences) { - using E = TypeParam; - using result_type = typename E::result_type; - - E rng; - (void)rng(); // Discard one value. - - constexpr int kNumOutputs = 64; - result_type a[kNumOutputs]; - result_type b[kNumOutputs]; - std::fill(std::begin(b), std::end(b), 0); - - // Fill a using Fill or generate, depending on the engine type. - { - E x = rng; - MyFill(x, absl::MakeSpan(a)); - } - - // Fill b using std::generate(). - { - E x = rng; - std::generate(std::begin(b), std::end(b), x); - } - - // Test that generated sequence changed as sequence of bits, i.e. if about - // half of the bites were flipped between two non-correlated values. - size_t changed_bits = 0; - size_t unchanged_bits = 0; - size_t total_set = 0; - size_t total_bits = 0; - size_t equal_count = 0; - for (size_t i = 0; i < kNumOutputs; ++i) { - equal_count += (a[i] == b[i]) ? 1 : 0; - std::bitset<sizeof(result_type) * 8> bitset(a[i] ^ b[i]); - changed_bits += bitset.count(); - unchanged_bits += bitset.size() - bitset.count(); - - std::bitset<sizeof(result_type) * 8> a_set(a[i]); - std::bitset<sizeof(result_type) * 8> b_set(b[i]); - total_set += a_set.count() + b_set.count(); - total_bits += 2 * 8 * sizeof(result_type); - } - // On average, half the bits are changed between two calls. - EXPECT_LE(changed_bits, 0.60 * (changed_bits + unchanged_bits)); - EXPECT_GE(changed_bits, 0.40 * (changed_bits + unchanged_bits)); - - // verify using a quick normal-approximation to the binomial. - EXPECT_NEAR(total_set, total_bits * 0.5, 4 * std::sqrt(total_bits)) - << "@" << total_set / static_cast<double>(total_bits); - - // Also, A[i] == B[i] with probability (1/range) * N. - // Give this a pretty wide latitude, though. - const double kExpected = kNumOutputs / (1.0 * sizeof(result_type) * 8); - EXPECT_LE(equal_count, 1.0 + kExpected); -} - -} // namespace - -/* -$ nanobenchmarks 1 RandenPool construct -$ nanobenchmarks 1 PoolURBG construct - -RandenPool<uint32_t> | 1 | 1000 | 48482.00 ticks | 48.48 ticks | 13.9 ns -RandenPool<uint32_t> | 10 | 2000 | 1028795.00 ticks | 51.44 ticks | 14.7 ns -RandenPool<uint32_t> | 100 | 1000 | 5119968.00 ticks | 51.20 ticks | 14.6 ns -RandenPool<uint32_t> | 1000 | 500 | 25867936.00 ticks | 51.74 ticks | 14.8 ns - -RandenPool<uint64_t> | 1 | 1000 | 49921.00 ticks | 49.92 ticks | 14.3 ns -RandenPool<uint64_t> | 10 | 2000 | 1208269.00 ticks | 60.41 ticks | 17.3 ns -RandenPool<uint64_t> | 100 | 1000 | 5844955.00 ticks | 58.45 ticks | 16.7 ns -RandenPool<uint64_t> | 1000 | 500 | 28767404.00 ticks | 57.53 ticks | 16.4 ns - -PoolURBG<uint32_t,8> | 1 | 1000 | 86431.00 ticks | 86.43 ticks | 24.7 ns -PoolURBG<uint32_t,8> | 10 | 1000 | 206191.00 ticks | 20.62 ticks | 5.9 ns -PoolURBG<uint32_t,8> | 100 | 1000 | 1516049.00 ticks | 15.16 ticks | 4.3 ns -PoolURBG<uint32_t,8> | 1000 | 500 | 7613936.00 ticks | 15.23 ticks | 4.4 ns - -PoolURBG<uint64_t,4> | 1 | 1000 | 96668.00 ticks | 96.67 ticks | 27.6 ns -PoolURBG<uint64_t,4> | 10 | 1000 | 282423.00 ticks | 28.24 ticks | 8.1 ns -PoolURBG<uint64_t,4> | 100 | 1000 | 2609587.00 ticks | 26.10 ticks | 7.5 ns -PoolURBG<uint64_t,4> | 1000 | 500 | 12408757.00 ticks | 24.82 ticks | 7.1 ns - -*/ |