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authorGravatar Abseil Team <absl-team@google.com>2019-06-21 13:11:42 -0700
committerGravatar Gennadiy Rozental <rogeeff@google.com>2019-06-21 16:18:10 -0400
commite9324d926a9189e222741fce6e676f0944661a72 (patch)
treea08568a709940c376454da34c9d8aac021378e5f /absl/random/internal/pool_urbg_test.cc
parent43ef2148c0936ebf7cb4be6b19927a9d9d145b8f (diff)
Export of internal Abseil changes.
-- 7a6ff16a85beb730c172d5d25cf1b5e1be885c56 by Laramie Leavitt <lar@google.com>: Internal change. PiperOrigin-RevId: 254454546 -- ff8f9bafaefc26d451f576ea4a06d150aed63f6f by Andy Soffer <asoffer@google.com>: Internal changes PiperOrigin-RevId: 254451562 -- deefc5b651b479ce36f0b4ef203e119c0c8936f2 by CJ Johnson <johnsoncj@google.com>: Account for subtracting unsigned values from the size of InlinedVector PiperOrigin-RevId: 254450625 -- 3c677316a27bcadc17e41957c809ca472d5fef14 by Andy Soffer <asoffer@google.com>: Add C++17's std::make_from_tuple to absl/utility/utility.h PiperOrigin-RevId: 254411573 -- 4ee3536a918830eeec402a28fc31a62c7c90b940 by CJ Johnson <johnsoncj@google.com>: Adds benchmark for the rest of the InlinedVector public API PiperOrigin-RevId: 254408378 -- e5a21a00700ee83498ff1efbf649169756463ee4 by CJ Johnson <johnsoncj@google.com>: Updates the definition of InlinedVector::shrink_to_fit() to be exception safe and adds exception safety tests for it. PiperOrigin-RevId: 254401387 -- 2ea82e72b86d82d78b4e4712a63a55981b53c64b by Laramie Leavitt <lar@google.com>: Use absl::InsecureBitGen in place of std::mt19937 in tests absl/random/...distribution_test.cc PiperOrigin-RevId: 254289444 -- fa099e02c413a7ffda732415e8105cad26a90337 by Andy Soffer <asoffer@google.com>: Internal changes PiperOrigin-RevId: 254286334 -- ce34b7f36933b30cfa35b9c9a5697a792b5666e4 by Andy Soffer <asoffer@google.com>: Internal changes PiperOrigin-RevId: 254273059 -- 6f9c473da7c2090c2e85a37c5f00622e8a912a89 by Jorg Brown <jorg@google.com>: Change absl::container_internal::CompressedTuple to instantiate its internal Storage class with the name of the type it's holding, rather than the name of the Tuple. This is not an externally-visible change, other than less compiler memory is used and less debug information is generated. PiperOrigin-RevId: 254269285 -- 8bd3c186bf2fc0c55d8a2dd6f28a5327502c9fba by Andy Soffer <asoffer@google.com>: Adding short-hand IntervalClosed for IntervalClosedClosed and IntervalOpen for IntervalOpenOpen. PiperOrigin-RevId: 254252419 -- ea957f99b6a04fccd42aa05605605f3b44b1ecfd by Abseil Team <absl-team@google.com>: Do not directly use __SIZEOF_INT128__. In order to avoid linker errors when building with clang-cl (__fixunsdfti, __udivti3 and __fixunssfti are undefined), this CL uses ABSL_HAVE_INTRINSIC_INT128 which is not defined for clang-cl. PiperOrigin-RevId: 254250739 -- 89ab385cd26b34d64130bce856253aaba96d2345 by Andy Soffer <asoffer@google.com>: Internal changes PiperOrigin-RevId: 254242321 -- cffc793d93eca6d6bdf7de733847b6ab4a255ae9 by CJ Johnson <johnsoncj@google.com>: Adds benchmark for InlinedVector::reserve(size_type) PiperOrigin-RevId: 254199226 -- c90c7a9fa3c8f0c9d5114036979548b055ea2f2a by Gennadiy Rozental <rogeeff@google.com>: Import of CCTZ from GitHub. PiperOrigin-RevId: 254072387 -- c4c388beae016c9570ab54ffa1d52660e4a85b7b by Laramie Leavitt <lar@google.com>: Internal cleanup. PiperOrigin-RevId: 254062381 -- d3c992e221cc74e5372d0c8fa410170b6a43c062 by Tom Manshreck <shreck@google.com>: Update distributions.h to Abseil standards PiperOrigin-RevId: 254054946 -- d15ad0035c34ef11b14fadc5a4a2d3ec415f5518 by CJ Johnson <johnsoncj@google.com>: Removes functions with only one caller from the implementation details of InlinedVector by manually inlining the definitions PiperOrigin-RevId: 254005427 -- 2f37e807efc3a8ef1f4b539bdd379917d4151520 by Andy Soffer <asoffer@google.com>: Initial release of Abseil Random PiperOrigin-RevId: 253999861 -- 24ed1694b6430791d781ed533a8f8ccf6cac5856 by CJ Johnson <johnsoncj@google.com>: Updates the definition of InlinedVector::assign(...)/InlinedVector::operator=(...) to new, exception-safe implementations with exception safety tests to boot PiperOrigin-RevId: 253993691 -- 5613d95f5a7e34a535cfaeadce801441e990843e by CJ Johnson <johnsoncj@google.com>: Adds benchmarks for InlinedVector::shrink_to_fit() PiperOrigin-RevId: 253989647 -- 2a96ddfdac40bbb8cb6a7f1aeab90917067c6e63 by Abseil Team <absl-team@google.com>: Initial release of Abseil Random PiperOrigin-RevId: 253927497 -- bf1aff8fc9ffa921ad74643e9525ecf25b0d8dc1 by Andy Soffer <asoffer@google.com>: Initial release of Abseil Random PiperOrigin-RevId: 253920512 -- bfc03f4a3dcda3cf3a4b84bdb84cda24e3394f41 by Laramie Leavitt <lar@google.com>: Internal change. PiperOrigin-RevId: 253886486 -- 05036cfcc078ca7c5f581a00dfb0daed568cbb69 by Eric Fiselier <ericwf@google.com>: Don't include `winsock2.h` because it drags in `windows.h` and friends, and they define awful macros like OPAQUE, ERROR, and more. This has the potential to break abseil users. Instead we only forward declare `timeval` and require Windows users include `winsock2.h` themselves. This is both inconsistent and poor QoI, but so including 'windows.h' is bad too. PiperOrigin-RevId: 253852615 GitOrigin-RevId: 7a6ff16a85beb730c172d5d25cf1b5e1be885c56 Change-Id: Icd6aff87da26f29ec8915da856f051129987cef6
Diffstat (limited to 'absl/random/internal/pool_urbg_test.cc')
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diff --git a/absl/random/internal/pool_urbg_test.cc b/absl/random/internal/pool_urbg_test.cc
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+// 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
+
+*/