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Diffstat (limited to 'absl/container/internal/raw_hash_set_test.cc')
| -rw-r--r-- | absl/container/internal/raw_hash_set_test.cc | 1961 |
1 files changed, 1961 insertions, 0 deletions
diff --git a/absl/container/internal/raw_hash_set_test.cc b/absl/container/internal/raw_hash_set_test.cc new file mode 100644 index 000000000000..f59a19b4a62d --- /dev/null +++ b/absl/container/internal/raw_hash_set_test.cc @@ -0,0 +1,1961 @@ +// Copyright 2018 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 +// +// http://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/container/internal/raw_hash_set.h" + +#include <array> +#include <cmath> +#include <cstdint> +#include <deque> +#include <functional> +#include <memory> +#include <numeric> +#include <random> +#include <string> + +#include "gmock/gmock.h" +#include "gtest/gtest.h" +#include "absl/base/attributes.h" +#include "absl/base/internal/cycleclock.h" +#include "absl/base/internal/raw_logging.h" +#include "absl/container/internal/container_memory.h" +#include "absl/container/internal/hash_function_defaults.h" +#include "absl/container/internal/hash_policy_testing.h" +#include "absl/container/internal/hashtable_debug.h" +#include "absl/strings/string_view.h" + +namespace absl { +namespace container_internal { + +struct RawHashSetTestOnlyAccess { + template <typename C> + static auto GetSlots(const C& c) -> decltype(c.slots_) { + return c.slots_; + } +}; + +namespace { + +using ::testing::DoubleNear; +using ::testing::ElementsAre; +using ::testing::Optional; +using ::testing::Pair; +using ::testing::UnorderedElementsAre; + +TEST(Util, NormalizeCapacity) { + constexpr size_t kMinCapacity = Group::kWidth - 1; + EXPECT_EQ(kMinCapacity, NormalizeCapacity(0)); + EXPECT_EQ(kMinCapacity, NormalizeCapacity(1)); + EXPECT_EQ(kMinCapacity, NormalizeCapacity(2)); + EXPECT_EQ(kMinCapacity, NormalizeCapacity(kMinCapacity)); + EXPECT_EQ(kMinCapacity * 2 + 1, NormalizeCapacity(kMinCapacity + 1)); + EXPECT_EQ(kMinCapacity * 2 + 1, NormalizeCapacity(kMinCapacity + 2)); +} + +TEST(Util, probe_seq) { + probe_seq<16> seq(0, 127); + auto gen = [&]() { + size_t res = seq.offset(); + seq.next(); + return res; + }; + std::vector<size_t> offsets(8); + std::generate_n(offsets.begin(), 8, gen); + EXPECT_THAT(offsets, ElementsAre(0, 16, 48, 96, 32, 112, 80, 64)); + seq = probe_seq<16>(128, 127); + std::generate_n(offsets.begin(), 8, gen); + EXPECT_THAT(offsets, ElementsAre(0, 16, 48, 96, 32, 112, 80, 64)); +} + +TEST(BitMask, Smoke) { + EXPECT_FALSE((BitMask<uint8_t, 8>(0))); + EXPECT_TRUE((BitMask<uint8_t, 8>(5))); + + EXPECT_THAT((BitMask<uint8_t, 8>(0)), ElementsAre()); + EXPECT_THAT((BitMask<uint8_t, 8>(0x1)), ElementsAre(0)); + EXPECT_THAT((BitMask<uint8_t, 8>(0x2)), ElementsAre(1)); + EXPECT_THAT((BitMask<uint8_t, 8>(0x3)), ElementsAre(0, 1)); + EXPECT_THAT((BitMask<uint8_t, 8>(0x4)), ElementsAre(2)); + EXPECT_THAT((BitMask<uint8_t, 8>(0x5)), ElementsAre(0, 2)); + EXPECT_THAT((BitMask<uint8_t, 8>(0x55)), ElementsAre(0, 2, 4, 6)); + EXPECT_THAT((BitMask<uint8_t, 8>(0xAA)), ElementsAre(1, 3, 5, 7)); +} + +TEST(BitMask, WithShift) { + // See the non-SSE version of Group for details on what this math is for. + uint64_t ctrl = 0x1716151413121110; + uint64_t hash = 0x12; + constexpr uint64_t msbs = 0x8080808080808080ULL; + constexpr uint64_t lsbs = 0x0101010101010101ULL; + auto x = ctrl ^ (lsbs * hash); + uint64_t mask = (x - lsbs) & ~x & msbs; + EXPECT_EQ(0x0000000080800000, mask); + + BitMask<uint64_t, 8, 3> b(mask); + EXPECT_EQ(*b, 2); +} + +TEST(BitMask, LeadingTrailing) { + EXPECT_EQ((BitMask<uint32_t, 16>(0b0001101001000000).LeadingZeros()), 3); + EXPECT_EQ((BitMask<uint32_t, 16>(0b0001101001000000).TrailingZeros()), 6); + + EXPECT_EQ((BitMask<uint32_t, 16>(0b0000000000000001).LeadingZeros()), 15); + EXPECT_EQ((BitMask<uint32_t, 16>(0b0000000000000001).TrailingZeros()), 0); + + EXPECT_EQ((BitMask<uint32_t, 16>(0b1000000000000000).LeadingZeros()), 0); + EXPECT_EQ((BitMask<uint32_t, 16>(0b1000000000000000).TrailingZeros()), 15); + + EXPECT_EQ((BitMask<uint64_t, 8, 3>(0x0000008080808000).LeadingZeros()), 3); + EXPECT_EQ((BitMask<uint64_t, 8, 3>(0x0000008080808000).TrailingZeros()), 1); + + EXPECT_EQ((BitMask<uint64_t, 8, 3>(0x0000000000000080).LeadingZeros()), 7); + EXPECT_EQ((BitMask<uint64_t, 8, 3>(0x0000000000000080).TrailingZeros()), 0); + + EXPECT_EQ((BitMask<uint64_t, 8, 3>(0x8000000000000000).LeadingZeros()), 0); + EXPECT_EQ((BitMask<uint64_t, 8, 3>(0x8000000000000000).TrailingZeros()), 7); +} + +TEST(Group, EmptyGroup) { + for (h2_t h = 0; h != 128; ++h) EXPECT_FALSE(Group{EmptyGroup()}.Match(h)); +} + +#if SWISSTABLE_HAVE_SSE2 +TEST(Group, Match) { + ctrl_t group[] = {kEmpty, 1, kDeleted, 3, kEmpty, 5, kSentinel, 7, + 7, 5, 3, 1, 1, 1, 1, 1}; + EXPECT_THAT(Group{group}.Match(0), ElementsAre()); + EXPECT_THAT(Group{group}.Match(1), ElementsAre(1, 11, 12, 13, 14, 15)); + EXPECT_THAT(Group{group}.Match(3), ElementsAre(3, 10)); + EXPECT_THAT(Group{group}.Match(5), ElementsAre(5, 9)); + EXPECT_THAT(Group{group}.Match(7), ElementsAre(7, 8)); +} + +TEST(Group, MatchEmpty) { + ctrl_t group[] = {kEmpty, 1, kDeleted, 3, kEmpty, 5, kSentinel, 7, + 7, 5, 3, 1, 1, 1, 1, 1}; + EXPECT_THAT(Group{group}.MatchEmpty(), ElementsAre(0, 4)); +} + +TEST(Group, MatchEmptyOrDeleted) { + ctrl_t group[] = {kEmpty, 1, kDeleted, 3, kEmpty, 5, kSentinel, 7, + 7, 5, 3, 1, 1, 1, 1, 1}; + EXPECT_THAT(Group{group}.MatchEmptyOrDeleted(), ElementsAre(0, 2, 4)); +} +#else +TEST(Group, Match) { + ctrl_t group[] = {kEmpty, 1, 2, kDeleted, 2, 1, kSentinel, 1}; + EXPECT_THAT(Group{group}.Match(0), ElementsAre()); + EXPECT_THAT(Group{group}.Match(1), ElementsAre(1, 5, 7)); + EXPECT_THAT(Group{group}.Match(2), ElementsAre(2, 4)); +} +TEST(Group, MatchEmpty) { + ctrl_t group[] = {kEmpty, 1, 2, kDeleted, 2, 1, kSentinel, 1}; + EXPECT_THAT(Group{group}.MatchEmpty(), ElementsAre(0)); +} + +TEST(Group, MatchEmptyOrDeleted) { + ctrl_t group[] = {kEmpty, 1, 2, kDeleted, 2, 1, kSentinel, 1}; + EXPECT_THAT(Group{group}.MatchEmptyOrDeleted(), ElementsAre(0, 3)); +} +#endif + +TEST(Batch, DropDeletes) { + constexpr size_t kCapacity = 63; + constexpr size_t kGroupWidth = container_internal::Group::kWidth; + std::vector<ctrl_t> ctrl(kCapacity + 1 + kGroupWidth); + ctrl[kCapacity] = kSentinel; + std::vector<ctrl_t> pattern = {kEmpty, 2, kDeleted, 2, kEmpty, 1, kDeleted}; + for (size_t i = 0; i != kCapacity; ++i) { + ctrl[i] = pattern[i % pattern.size()]; + if (i < kGroupWidth - 1) + ctrl[i + kCapacity + 1] = pattern[i % pattern.size()]; + } + ConvertDeletedToEmptyAndFullToDeleted(ctrl.data(), kCapacity); + ASSERT_EQ(ctrl[kCapacity], kSentinel); + for (size_t i = 0; i < kCapacity + 1 + kGroupWidth; ++i) { + ctrl_t expected = pattern[i % (kCapacity + 1) % pattern.size()]; + if (i == kCapacity) expected = kSentinel; + if (expected == kDeleted) expected = kEmpty; + if (IsFull(expected)) expected = kDeleted; + EXPECT_EQ(ctrl[i], expected) + << i << " " << int{pattern[i % pattern.size()]}; + } +} + +TEST(Group, CountLeadingEmptyOrDeleted) { + const std::vector<ctrl_t> empty_examples = {kEmpty, kDeleted}; + const std::vector<ctrl_t> full_examples = {0, 1, 2, 3, 5, 9, 127, kSentinel}; + + for (ctrl_t empty : empty_examples) { + std::vector<ctrl_t> e(Group::kWidth, empty); + EXPECT_EQ(Group::kWidth, Group{e.data()}.CountLeadingEmptyOrDeleted()); + for (ctrl_t full : full_examples) { + for (size_t i = 0; i != Group::kWidth; ++i) { + std::vector<ctrl_t> f(Group::kWidth, empty); + f[i] = full; + EXPECT_EQ(i, Group{f.data()}.CountLeadingEmptyOrDeleted()); + } + std::vector<ctrl_t> f(Group::kWidth, empty); + f[Group::kWidth * 2 / 3] = full; + f[Group::kWidth / 2] = full; + EXPECT_EQ( + Group::kWidth / 2, Group{f.data()}.CountLeadingEmptyOrDeleted()); + } + } +} + +struct IntPolicy { + using slot_type = int64_t; + using key_type = int64_t; + using init_type = int64_t; + + static void construct(void*, int64_t* slot, int64_t v) { *slot = v; } + static void destroy(void*, int64_t*) {} + static void transfer(void*, int64_t* new_slot, int64_t* old_slot) { + *new_slot = *old_slot; + } + + static int64_t& element(slot_type* slot) { return *slot; } + + template <class F> + static auto apply(F&& f, int64_t x) -> decltype(std::forward<F>(f)(x, x)) { + return std::forward<F>(f)(x, x); + } +}; + +class StringPolicy { + template <class F, class K, class V, + class = typename std::enable_if< + std::is_convertible<const K&, absl::string_view>::value>::type> + decltype(std::declval<F>()( + std::declval<const absl::string_view&>(), std::piecewise_construct, + std::declval<std::tuple<K>>(), + std::declval<V>())) static apply_impl(F&& f, + std::pair<std::tuple<K>, V> p) { + const absl::string_view& key = std::get<0>(p.first); + return std::forward<F>(f)(key, std::piecewise_construct, std::move(p.first), + std::move(p.second)); + } + + public: + struct slot_type { + struct ctor {}; + + template <class... Ts> + slot_type(ctor, Ts&&... ts) : pair(std::forward<Ts>(ts)...) {} + + std::pair<std::string, std::string> pair; + }; + + using key_type = std::string; + using init_type = std::pair<std::string, std::string>; + + template <class allocator_type, class... Args> + static void construct(allocator_type* alloc, slot_type* slot, Args... args) { + std::allocator_traits<allocator_type>::construct( + *alloc, slot, typename slot_type::ctor(), std::forward<Args>(args)...); + } + + template <class allocator_type> + static void destroy(allocator_type* alloc, slot_type* slot) { + std::allocator_traits<allocator_type>::destroy(*alloc, slot); + } + + template <class allocator_type> + static void transfer(allocator_type* alloc, slot_type* new_slot, + slot_type* old_slot) { + construct(alloc, new_slot, std::move(old_slot->pair)); + destroy(alloc, old_slot); + } + + static std::pair<std::string, std::string>& element(slot_type* slot) { + return slot->pair; + } + + template <class F, class... Args> + static auto apply(F&& f, Args&&... args) + -> decltype(apply_impl(std::forward<F>(f), + PairArgs(std::forward<Args>(args)...))) { + return apply_impl(std::forward<F>(f), + PairArgs(std::forward<Args>(args)...)); + } +}; + +struct StringHash : absl::Hash<absl::string_view> { + using is_transparent = void; +}; +struct StringEq : std::equal_to<absl::string_view> { + using is_transparent = void; +}; + +struct StringTable + : raw_hash_set<StringPolicy, StringHash, StringEq, std::allocator<int>> { + using Base = typename StringTable::raw_hash_set; + StringTable() {} + using Base::Base; +}; + +struct IntTable + : raw_hash_set<IntPolicy, container_internal::hash_default_hash<int64_t>, + std::equal_to<int64_t>, std::allocator<int64_t>> { + using Base = typename IntTable::raw_hash_set; + IntTable() {} + using Base::Base; +}; + +struct BadFastHash { + template <class T> + size_t operator()(const T&) const { + return 0; + } +}; + +struct BadTable : raw_hash_set<IntPolicy, BadFastHash, std::equal_to<int>, + std::allocator<int>> { + using Base = typename BadTable::raw_hash_set; + BadTable() {} + using Base::Base; +}; + +TEST(Table, EmptyFunctorOptimization) { + static_assert(std::is_empty<std::equal_to<absl::string_view>>::value, ""); + static_assert(std::is_empty<std::allocator<int>>::value, ""); + + struct MockTable { + void* ctrl; + void* slots; + size_t size; + size_t capacity; + size_t growth_left; + }; + struct StatelessHash { + size_t operator()(absl::string_view) const { return 0; } + }; + struct StatefulHash : StatelessHash { + size_t dummy; + }; + + EXPECT_EQ( + sizeof(MockTable), + sizeof( + raw_hash_set<StringPolicy, StatelessHash, + std::equal_to<absl::string_view>, std::allocator<int>>)); + + EXPECT_EQ( + sizeof(MockTable) + sizeof(StatefulHash), + sizeof( + raw_hash_set<StringPolicy, StatefulHash, + std::equal_to<absl::string_view>, std::allocator<int>>)); +} + +TEST(Table, Empty) { + IntTable t; + EXPECT_EQ(0, t.size()); + EXPECT_TRUE(t.empty()); +} + +#ifdef __GNUC__ +template <class T> +ABSL_ATTRIBUTE_ALWAYS_INLINE inline void DoNotOptimize(const T& v) { + asm volatile("" : : "r,m"(v) : "memory"); +} +#endif + +TEST(Table, Prefetch) { + IntTable t; + t.emplace(1); + // Works for both present and absent keys. + t.prefetch(1); + t.prefetch(2); + + // Do not run in debug mode, when prefetch is not implemented, or when + // sanitizers are enabled. +#if defined(NDEBUG) && defined(__GNUC__) && !defined(ADDRESS_SANITIZER) && \ + !defined(MEMORY_SANITIZER) && !defined(THREAD_SANITIZER) && \ + !defined(UNDEFINED_BEHAVIOR_SANITIZER) + const auto now = [] { return absl::base_internal::CycleClock::Now(); }; + + static constexpr int size = 1000000; + for (int i = 0; i < size; ++i) t.insert(i); + + int64_t no_prefetch = 0, prefetch = 0; + for (int iter = 0; iter < 10; ++iter) { + int64_t time = now(); + for (int i = 0; i < size; ++i) { + DoNotOptimize(t.find(i)); + } + no_prefetch += now() - time; + + time = now(); + for (int i = 0; i < size; ++i) { + t.prefetch(i + 20); + DoNotOptimize(t.find(i)); + } + prefetch += now() - time; + } + + // no_prefetch is at least 30% slower. + EXPECT_GE(1.0 * no_prefetch / prefetch, 1.3); +#endif +} + +TEST(Table, LookupEmpty) { + IntTable t; + auto it = t.find(0); + EXPECT_TRUE(it == t.end()); +} + +TEST(Table, Insert1) { + IntTable t; + EXPECT_TRUE(t.find(0) == t.end()); + auto res = t.emplace(0); + EXPECT_TRUE(res.second); + EXPECT_THAT(*res.first, 0); + EXPECT_EQ(1, t.size()); + EXPECT_THAT(*t.find(0), 0); +} + +TEST(Table, Insert2) { + IntTable t; + EXPECT_TRUE(t.find(0) == t.end()); + auto res = t.emplace(0); + EXPECT_TRUE(res.second); + EXPECT_THAT(*res.first, 0); + EXPECT_EQ(1, t.size()); + EXPECT_TRUE(t.find(1) == t.end()); + res = t.emplace(1); + EXPECT_TRUE(res.second); + EXPECT_THAT(*res.first, 1); + EXPECT_EQ(2, t.size()); + EXPECT_THAT(*t.find(0), 0); + EXPECT_THAT(*t.find(1), 1); +} + +TEST(Table, InsertCollision) { + BadTable t; + EXPECT_TRUE(t.find(1) == t.end()); + auto res = t.emplace(1); + EXPECT_TRUE(res.second); + EXPECT_THAT(*res.first, 1); + EXPECT_EQ(1, t.size()); + + EXPECT_TRUE(t.find(2) == t.end()); + res = t.emplace(2); + EXPECT_THAT(*res.first, 2); + EXPECT_TRUE(res.second); + EXPECT_EQ(2, t.size()); + + EXPECT_THAT(*t.find(1), 1); + EXPECT_THAT(*t.find(2), 2); +} + +// Test that we do not add existent element in case we need to search through +// many groups with deleted elements +TEST(Table, InsertCollisionAndFindAfterDelete) { + BadTable t; // all elements go to the same group. + // Have at least 2 groups with Group::kWidth collisions + // plus some extra collisions in the last group. + constexpr size_t kNumInserts = Group::kWidth * 2 + 5; + for (size_t i = 0; i < kNumInserts; ++i) { + auto res = t.emplace(i); + EXPECT_TRUE(res.second); + EXPECT_THAT(*res.first, i); + EXPECT_EQ(i + 1, t.size()); + } + + // Remove elements one by one and check + // that we still can find all other elements. + for (size_t i = 0; i < kNumInserts; ++i) { + EXPECT_EQ(1, t.erase(i)) << i; + for (size_t j = i + 1; j < kNumInserts; ++j) { + EXPECT_THAT(*t.find(j), j); + auto res = t.emplace(j); + EXPECT_FALSE(res.second) << i << " " << j; + EXPECT_THAT(*res.first, j); + EXPECT_EQ(kNumInserts - i - 1, t.size()); + } + } + EXPECT_TRUE(t.empty()); +} + +TEST(Table, LazyEmplace) { + StringTable t; + bool called = false; + auto it = t.lazy_emplace("abc", [&](const StringTable::constructor& f) { + called = true; + f("abc", "ABC"); + }); + EXPECT_TRUE(called); + EXPECT_THAT(*it, Pair("abc", "ABC")); + called = false; + it = t.lazy_emplace("abc", [&](const StringTable::constructor& f) { + called = true; + f("abc", "DEF"); + }); + EXPECT_FALSE(called); + EXPECT_THAT(*it, Pair("abc", "ABC")); +} + +TEST(Table, ContainsEmpty) { + IntTable t; + + EXPECT_FALSE(t.contains(0)); +} + +TEST(Table, Contains1) { + IntTable t; + + EXPECT_TRUE(t.insert(0).second); + EXPECT_TRUE(t.contains(0)); + EXPECT_FALSE(t.contains(1)); + + EXPECT_EQ(1, t.erase(0)); + EXPECT_FALSE(t.contains(0)); +} + +TEST(Table, Contains2) { + IntTable t; + + EXPECT_TRUE(t.insert(0).second); + EXPECT_TRUE(t.contains(0)); + EXPECT_FALSE(t.contains(1)); + + t.clear(); + EXPECT_FALSE(t.contains(0)); +} + +int decompose_constructed; +struct DecomposeType { + DecomposeType(int i) : i(i) { // NOLINT + ++decompose_constructed; + } + + explicit DecomposeType(const char* d) : DecomposeType(*d) {} + + int i; +}; + +struct DecomposeHash { + using is_transparent = void; + size_t operator()(DecomposeType a) const { return a.i; } + size_t operator()(int a) const { return a; } + size_t operator()(const char* a) const { return *a; } +}; + +struct DecomposeEq { + using is_transparent = void; + bool operator()(DecomposeType a, DecomposeType b) const { return a.i == b.i; } + bool operator()(DecomposeType a, int b) const { return a.i == b; } + bool operator()(DecomposeType a, const char* b) const { return a.i == *b; } +}; + +struct DecomposePolicy { + using slot_type = DecomposeType; + using key_type = DecomposeType; + using init_type = DecomposeType; + + template <typename T> + static void construct(void*, DecomposeType* slot, T&& v) { + *slot = DecomposeType(std::forward<T>(v)); + } + static void destroy(void*, DecomposeType*) {} + static DecomposeType& element(slot_type* slot) { return *slot; } + + template <class F, class T> + static auto apply(F&& f, const T& x) -> decltype(std::forward<F>(f)(x, x)) { + return std::forward<F>(f)(x, x); + } +}; + +template <typename Hash, typename Eq> +void TestDecompose(bool construct_three) { + DecomposeType elem{0}; + const int one = 1; + const char* three_p = "3"; + const auto& three = three_p; + + raw_hash_set<DecomposePolicy, Hash, Eq, std::allocator<int>> set1; + + decompose_constructed = 0; + int expected_constructed = 0; + EXPECT_EQ(expected_constructed, decompose_constructed); + set1.insert(elem); + EXPECT_EQ(expected_constructed, decompose_constructed); + set1.insert(1); + EXPECT_EQ(++expected_constructed, decompose_constructed); + set1.emplace("3"); + EXPECT_EQ(++expected_constructed, decompose_constructed); + EXPECT_EQ(expected_constructed, decompose_constructed); + + { // insert(T&&) + set1.insert(1); + EXPECT_EQ(expected_constructed, decompose_constructed); + } + + { // insert(const T&) + set1.insert(one); + EXPECT_EQ(expected_constructed, decompose_constructed); + } + + { // insert(hint, T&&) + set1.insert(set1.begin(), 1); + EXPECT_EQ(expected_constructed, decompose_constructed); + } + + { // insert(hint, const T&) + set1.insert(set1.begin(), one); + EXPECT_EQ(expected_constructed, decompose_constructed); + } + + { // emplace(...) + set1.emplace(1); + EXPECT_EQ(expected_constructed, decompose_constructed); + set1.emplace("3"); + expected_constructed += construct_three; + EXPECT_EQ(expected_constructed, decompose_constructed); + set1.emplace(one); + EXPECT_EQ(expected_constructed, decompose_constructed); + set1.emplace(three); + expected_constructed += construct_three; + EXPECT_EQ(expected_constructed, decompose_constructed); + } + + { // emplace_hint(...) + set1.emplace_hint(set1.begin(), 1); + EXPECT_EQ(expected_constructed, decompose_constructed); + set1.emplace_hint(set1.begin(), "3"); + expected_constructed += construct_three; + EXPECT_EQ(expected_constructed, decompose_constructed); + set1.emplace_hint(set1.begin(), one); + EXPECT_EQ(expected_constructed, decompose_constructed); + set1.emplace_hint(set1.begin(), three); + expected_constructed += construct_three; + EXPECT_EQ(expected_constructed, decompose_constructed); + } +} + +TEST(Table, Decompose) { + TestDecompose<DecomposeHash, DecomposeEq>(false); + + struct TransparentHashIntOverload { + size_t operator()(DecomposeType a) const { return a.i; } + size_t operator()(int a) const { return a; } + }; + struct TransparentEqIntOverload { + bool operator()(DecomposeType a, DecomposeType b) const { + return a.i == b.i; + } + bool operator()(DecomposeType a, int b) const { return a.i == b; } + }; + TestDecompose<TransparentHashIntOverload, DecomposeEq>(true); + TestDecompose<TransparentHashIntOverload, TransparentEqIntOverload>(true); + TestDecompose<DecomposeHash, TransparentEqIntOverload>(true); +} + +// Returns the largest m such that a table with m elements has the same number +// of buckets as a table with n elements. +size_t MaxDensitySize(size_t n) { + IntTable t; + t.reserve(n); + for (size_t i = 0; i != n; ++i) t.emplace(i); + const size_t c = t.bucket_count(); + while (c == t.bucket_count()) t.emplace(n++); + return t.size() - 1; +} + +struct Modulo1000Hash { + size_t operator()(int x) const { return x % 1000; } +}; + +struct Modulo1000HashTable + : public raw_hash_set<IntPolicy, Modulo1000Hash, std::equal_to<int>, + std::allocator<int>> {}; + +// Test that rehash with no resize happen in case of many deleted slots. +TEST(Table, RehashWithNoResize) { + Modulo1000HashTable t; + // Adding the same length (and the same hash) strings + // to have at least kMinFullGroups groups + // with Group::kWidth collisions. Then feel upto MaxDensitySize; + const size_t kMinFullGroups = 7; + std::vector<int> keys; + for (size_t i = 0; i < MaxDensitySize(Group::kWidth * kMinFullGroups); ++i) { + int k = i * 1000; + t.emplace(k); + keys.push_back(k); + } + const size_t capacity = t.capacity(); + + // Remove elements from all groups except the first and the last one. + // All elements removed from full groups will be marked as kDeleted. + const size_t erase_begin = Group::kWidth / 2; + const size_t erase_end = (t.size() / Group::kWidth - 1) * Group::kWidth; + for (size_t i = erase_begin; i < erase_end; ++i) { + EXPECT_EQ(1, t.erase(keys[i])) << i; + } + keys.erase(keys.begin() + erase_begin, keys.begin() + erase_end); + + auto last_key = keys.back(); + size_t last_key_num_probes = GetHashtableDebugNumProbes(t, last_key); + + // Make sure that we have to make a lot of probes for last key. + ASSERT_GT(last_key_num_probes, kMinFullGroups); + + int x = 1; + // Insert and erase one element, before inplace rehash happen. + while (last_key_num_probes == GetHashtableDebugNumProbes(t, last_key)) { + t.emplace(x); + ASSERT_EQ(capacity, t.capacity()); + // All elements should be there. + ASSERT_TRUE(t.find(x) != t.end()) << x; + for (const auto& k : keys) { + ASSERT_TRUE(t.find(k) != t.end()) << k; + } + t.erase(x); + ++x; + } +} + +TEST(Table, InsertEraseStressTest) { + IntTable t; + const size_t kMinElementCount = 250; + std::deque<int> keys; + size_t i = 0; + for (; i < MaxDensitySize(kMinElementCount); ++i) { + t.emplace(i); + keys.push_back(i); + } + const size_t kNumIterations = 1000000; + for (; i < kNumIterations; ++i) { + ASSERT_EQ(1, t.erase(keys.front())); + keys.pop_front(); + t.emplace(i); + keys.push_back(i); + } +} + +TEST(Table, InsertOverloads) { + StringTable t; + // These should all trigger the insert(init_type) overload. + t.insert({{}, {}}); + t.insert({"ABC", {}}); + t.insert({"DEF", "!!!"}); + + EXPECT_THAT(t, UnorderedElementsAre(Pair("", ""), Pair("ABC", ""), + Pair("DEF", "!!!"))); +} + +TEST(Table, LargeTable) { + IntTable t; + for (int64_t i = 0; i != 100000; ++i) t.emplace(i << 40); + for (int64_t i = 0; i != 100000; ++i) ASSERT_EQ(i << 40, *t.find(i << 40)); +} + +// Timeout if copy is quadratic as it was in Rust. +TEST(Table, EnsureNonQuadraticAsInRust) { + static const size_t kLargeSize = 1 << 15; + + IntTable t; + for (size_t i = 0; i != kLargeSize; ++i) { + t.insert(i); + } + + // If this is quadratic, the test will timeout. + IntTable t2; + for (const auto& entry : t) t2.insert(entry); +} + +TEST(Table, ClearBug) { + IntTable t; + constexpr size_t capacity = container_internal::Group::kWidth - 1; + constexpr size_t max_size = capacity / 2; + for (size_t i = 0; i < max_size; ++i) { + t.insert(i); + } + ASSERT_EQ(capacity, t.capacity()); + intptr_t original = reinterpret_cast<intptr_t>(&*t.find(2)); + t.clear(); + ASSERT_EQ(capacity, t.capacity()); + for (size_t i = 0; i < max_size; ++i) { + t.insert(i); + } + ASSERT_EQ(capacity, t.capacity()); + intptr_t second = reinterpret_cast<intptr_t>(&*t.find(2)); + // We are checking that original and second are close enough to each other + // that they are probably still in the same group. This is not strictly + // guaranteed. + EXPECT_LT(std::abs(original - second), + capacity * sizeof(IntTable::value_type)); +} + +TEST(Table, Erase) { + IntTable t; + EXPECT_TRUE(t.find(0) == t.end()); + auto res = t.emplace(0); + EXPECT_TRUE(res.second); + EXPECT_EQ(1, t.size()); + t.erase(res.first); + EXPECT_EQ(0, t.size()); + EXPECT_TRUE(t.find(0) == t.end()); +} + +// Collect N bad keys by following algorithm: +// 1. Create an empty table and reserve it to 2 * N. +// 2. Insert N random elements. +// 3. Take first Group::kWidth - 1 to bad_keys array. +// 4. Clear the table without resize. +// 5. Go to point 2 while N keys not collected +std::vector<int64_t> CollectBadMergeKeys(size_t N) { + static constexpr int kGroupSize = Group::kWidth - 1; + + auto topk_range = [](size_t b, size_t e, IntTable* t) -> std::vector<int64_t> { + for (size_t i = b; i != e; ++i) { + t->emplace(i); + } + std::vector<int64_t> res; + res.reserve(kGroupSize); + auto it = t->begin(); + for (size_t i = b; i != e && i != b + kGroupSize; ++i, ++it) { + res.push_back(*it); + } + return res; + }; + + std::vector<int64_t> bad_keys; + bad_keys.reserve(N); + IntTable t; + t.reserve(N * 2); + + for (size_t b = 0; bad_keys.size() < N; b += N) { + auto keys = topk_range(b, b + N, &t); + bad_keys.insert(bad_keys.end(), keys.begin(), keys.end()); + t.erase(t.begin(), t.end()); + EXPECT_TRUE(t.empty()); + } + return bad_keys; +} + +struct ProbeStats { + // Number of elements with specific probe length over all tested tables. + std::vector<size_t> all_probes_histogram; + // Ratios total_probe_length/size for every tested table. + std::vector<double> single_table_ratios; + + friend ProbeStats operator+(const ProbeStats& a, const ProbeStats& b) { + ProbeStats res = a; + res.all_probes_histogram.resize(std::max(res.all_probes_histogram.size(), + b.all_probes_histogram.size())); + std::transform(b.all_probes_histogram.begin(), b.all_probes_histogram.end(), + res.all_probes_histogram.begin(), + res.all_probes_histogram.begin(), std::plus<size_t>()); + res.single_table_ratios.insert(res.single_table_ratios.end(), + b.single_table_ratios.begin(), + b.single_table_ratios.end()); + return res; + } + + // Average ratio total_probe_length/size over tables. + double AvgRatio() const { + return std::accumulate(single_table_ratios.begin(), + single_table_ratios.end(), 0.0) / + single_table_ratios.size(); + } + + // Maximum ratio total_probe_length/size over tables. + double MaxRatio() const { + return *std::max_element(single_table_ratios.begin(), + single_table_ratios.end()); + } + + // Percentile ratio total_probe_length/size over tables. + double PercentileRatio(double Percentile = 0.95) const { + auto r = single_table_ratios; + auto mid = r.begin() + static_cast<size_t>(r.size() * Percentile); + if (mid != r.end()) { + std::nth_element(r.begin(), mid, r.end()); + return *mid; + } else { + return MaxRatio(); + } + } + + // Maximum probe length over all elements and all tables. + size_t MaxProbe() const { return all_probes_histogram.size(); } + + // Fraction of elements with specified probe length. + std::vector<double> ProbeNormalizedHistogram() const { + double total_elements = std::accumulate(all_probes_histogram.begin(), + all_probes_histogram.end(), 0ull); + std::vector<double> res; + for (size_t p : all_probes_histogram) { + res.push_back(p / total_elements); + } + return res; + } + + size_t PercentileProbe(double Percentile = 0.99) const { + size_t idx = 0; + for (double p : ProbeNormalizedHistogram()) { + if (Percentile > p) { + Percentile -= p; + ++idx; + } else { + return idx; + } + } + return idx; + } + + friend std::ostream& operator<<(std::ostream& out, const ProbeStats& s) { + out << "{AvgRatio:" << s.AvgRatio() << ", MaxRatio:" << s.MaxRatio() + << ", PercentileRatio:" << s.PercentileRatio() + << ", MaxProbe:" << s.MaxProbe() << ", Probes=["; + for (double p : s.ProbeNormalizedHistogram()) { + out << p << ","; + } + out << "]}"; + + return out; + } +}; + +struct ExpectedStats { + double avg_ratio; + double max_ratio; + std::vector<std::pair<double, double>> pecentile_ratios; + std::vector<std::pair<double, double>> pecentile_probes; + + friend std::ostream& operator<<(std::ostream& out, const ExpectedStats& s) { + out << "{AvgRatio:" << s.avg_ratio << ", MaxRatio:" << s.max_ratio + << ", PercentileRatios: ["; + for (auto el : s.pecentile_ratios) { + out << el.first << ":" << el.second << ", "; + } + out << "], PercentileProbes: ["; + for (auto el : s.pecentile_probes) { + out << el.first << ":" << el.second << ", "; + } + out << "]}"; + + return out; + } +}; + +void VerifyStats(size_t size, const ExpectedStats& exp, + const ProbeStats& stats) { + EXPECT_LT(stats.AvgRatio(), exp.avg_ratio) << size << " " << stats; + EXPECT_LT(stats.MaxRatio(), exp.max_ratio) << size << " " << stats; + for (auto pr : exp.pecentile_ratios) { + EXPECT_LE(stats.PercentileRatio(pr.first), pr.second) + << size << " " << pr.first << " " << stats; + } + + for (auto pr : exp.pecentile_probes) { + EXPECT_LE(stats.PercentileProbe(pr.first), pr.second) + << size << " " << pr.first << " " << stats; + } +} + +using ProbeStatsPerSize = std::map<size_t, ProbeStats>; + +// Collect total ProbeStats on num_iters iterations of the following algorithm: +// 1. Create new table and reserve it to keys.size() * 2 +// 2. Insert all keys xored with seed +// 3. Collect ProbeStats from final table. +ProbeStats CollectProbeStatsOnKeysXoredWithSeed(const std::vector<int64_t>& keys, + size_t num_iters) { + const size_t reserve_size = keys.size() * 2; + + ProbeStats stats; + + int64_t seed = 0x71b1a19b907d6e33; + while (num_iters--) { + seed = static_cast<int64_t>(static_cast<uint64_t>(seed) * 17 + 13); + IntTable t1; + t1.reserve(reserve_size); + for (const auto& key : keys) { + t1.emplace(key ^ seed); + } + + auto probe_histogram = GetHashtableDebugNumProbesHistogram(t1); + stats.all_probes_histogram.resize( + std::max(stats.all_probes_histogram.size(), probe_histogram.size())); + std::transform(probe_histogram.begin(), probe_histogram.end(), + stats.all_probes_histogram.begin(), + stats.all_probes_histogram.begin(), std::plus<size_t>()); + + size_t total_probe_seq_length = 0; + for (size_t i = 0; i < probe_histogram.size(); ++i) { + total_probe_seq_length += i * probe_histogram[i]; + } + stats.single_table_ratios.push_back(total_probe_seq_length * 1.0 / + keys.size()); + t1.erase(t1.begin(), t1.end()); + } + return stats; +} + +ExpectedStats XorSeedExpectedStats() { + constexpr bool kRandomizesInserts = +#if NDEBUG + false; +#else // NDEBUG + true; +#endif // NDEBUG + + // The effective load factor is larger in non-opt mode because we insert + // elements out of order. + switch (container_internal::Group::kWidth) { + case 8: + if (kRandomizesInserts) { + return {0.05, + 1.0, + {{0.95, 0.5}}, + {{0.95, 0}, {0.99, 2}, {0.999, 4}, {0.9999, 10}}}; + } else { + return {0.05, + 2.0, + {{0.95, 0.1}}, + {{0.95, 0}, {0.99, 2}, {0.999, 4}, {0.9999, 10}}}; + } + break; + case 16: + if (kRandomizesInserts) { + return {0.1, + 1.0, + {{0.95, 0.1}}, + {{0.95, 0}, {0.99, 1}, {0.999, 8}, {0.9999, 15}}}; + } else { + return {0.05, + 1.0, + {{0.95, 0.05}}, + {{0.95, 0}, {0.99, 1}, {0.999, 4}, {0.9999, 10}}}; + } + break; + default: + ABSL_RAW_LOG(FATAL, "%s", "Unknown Group width"); + } + return {}; +} +TEST(Table, DISABLED_EnsureNonQuadraticTopNXorSeedByProbeSeqLength) { + ProbeStatsPerSize stats; + std::vector<size_t> sizes = {Group::kWidth << 5, Group::kWidth << 10}; + for (size_t size : sizes) { + stats[size] = + CollectProbeStatsOnKeysXoredWithSeed(CollectBadMergeKeys(size), 200); + } + auto expected = XorSeedExpectedStats(); + for (size_t size : sizes) { + auto& stat = stats[size]; + VerifyStats(size, expected, stat); + } +} + +// Collect total ProbeStats on num_iters iterations of the following algorithm: +// 1. Create new table +// 2. Select 10% of keys and insert 10 elements key * 17 + j * 13 +// 3. Collect ProbeStats from final table +ProbeStats CollectProbeStatsOnLinearlyTransformedKeys( + const std::vector<int64_t>& keys, size_t num_iters) { + ProbeStats stats; + + std::random_device rd; + std::mt19937 rng(rd()); + auto linear_transform = [](size_t x, size_t y) { return x * 17 + y * 13; }; + std::uniform_int_distribution<size_t> dist(0, keys.size()-1); + while (num_iters--) { + IntTable t1; + size_t num_keys = keys.size() / 10; + size_t start = dist(rng); + for (size_t i = 0; i != num_keys; ++i) { + for (size_t j = 0; j != 10; ++j) { + t1.emplace(linear_transform(keys[(i + start) % keys.size()], j)); + } + } + + auto probe_histogram = GetHashtableDebugNumProbesHistogram(t1); + stats.all_probes_histogram.resize( + std::max(stats.all_probes_histogram.size(), probe_histogram.size())); + std::transform(probe_histogram.begin(), probe_histogram.end(), + stats.all_probes_histogram.begin(), + stats.all_probes_histogram.begin(), std::plus<size_t>()); + + size_t total_probe_seq_length = 0; + for (size_t i = 0; i < probe_histogram.size(); ++i) { + total_probe_seq_length += i * probe_histogram[i]; + } + stats.single_table_ratios.push_back(total_probe_seq_length * 1.0 / + t1.size()); + t1.erase(t1.begin(), t1.end()); + } + return stats; +} + +ExpectedStats LinearTransformExpectedStats() { + constexpr bool kRandomizesInserts = +#if NDEBUG + false; +#else // NDEBUG + true; +#endif // NDEBUG + + // The effective load factor is larger in non-opt mode because we insert + // elements out of order. + switch (container_internal::Group::kWidth) { + case 8: + if (kRandomizesInserts) { + return {0.1, + 0.5, + {{0.95, 0.3}}, + {{0.95, 0}, {0.99, 1}, {0.999, 8}, {0.9999, 15}}}; + } else { + return {0.15, + 0.5, + {{0.95, 0.3}}, + {{0.95, 0}, {0.99, 3}, {0.999, 15}, {0.9999, 25}}}; + } + break; + case 16: + if (kRandomizesInserts) { + return {0.1, + 0.4, + {{0.95, 0.3}}, + {{0.95, 0}, {0.99, 1}, {0.999, 8}, {0.9999, 15}}}; + } else { + return {0.05, + 0.2, + {{0.95, 0.1}}, + {{0.95, 0}, {0.99, 1}, {0.999, 6}, {0.9999, 10}}}; + } + break; + default: + ABSL_RAW_LOG(FATAL, "%s", "Unknown Group width"); + } + return {}; +} +TEST(Table, DISABLED_EnsureNonQuadraticTopNLinearTransformByProbeSeqLength) { + ProbeStatsPerSize stats; + std::vector<size_t> sizes = {Group::kWidth << 5, Group::kWidth << 10}; + for (size_t size : sizes) { + stats[size] = CollectProbeStatsOnLinearlyTransformedKeys( + CollectBadMergeKeys(size), 300); + } + auto expected = LinearTransformExpectedStats(); + for (size_t size : sizes) { + auto& stat = stats[size]; + VerifyStats(size, expected, stat); + } +} + +TEST(Table, EraseCollision) { + BadTable t; + + // 1 2 3 + t.emplace(1); + t.emplace(2); + t.emplace(3); + EXPECT_THAT(*t.find(1), 1); + EXPECT_THAT(*t.find(2), 2); + EXPECT_THAT(*t.find(3), 3); + EXPECT_EQ(3, t.size()); + + // 1 DELETED 3 + t.erase(t.find(2)); + EXPECT_THAT(*t.find(1), 1); + EXPECT_TRUE(t.find(2) == t.end()); + EXPECT_THAT(*t.find(3), 3); + EXPECT_EQ(2, t.size()); + + // DELETED DELETED 3 + t.erase(t.find(1)); + EXPECT_TRUE(t.find(1) == t.end()); + EXPECT_TRUE(t.find(2) == t.end()); + EXPECT_THAT(*t.find(3), 3); + EXPECT_EQ(1, t.size()); + + // DELETED DELETED DELETED + t.erase(t.find(3)); + EXPECT_TRUE(t.find(1) == t.end()); + EXPECT_TRUE(t.find(2) == t.end()); + EXPECT_TRUE(t.find(3) == t.end()); + EXPECT_EQ(0, t.size()); +} + +TEST(Table, EraseInsertProbing) { + BadTable t(100); + + // 1 2 3 4 + t.emplace(1); + t.emplace(2); + t.emplace(3); + t.emplace(4); + + // 1 DELETED 3 DELETED + t.erase(t.find(2)); + t.erase(t.find(4)); + + // 1 10 3 11 12 + t.emplace(10); + t.emplace(11); + t.emplace(12); + + EXPECT_EQ(5, t.size()); + EXPECT_THAT(t, UnorderedElementsAre(1, 10, 3, 11, 12)); +} + +TEST(Table, Clear) { + IntTable t; + EXPECT_TRUE(t.find(0) == t.end()); + t.clear(); + EXPECT_TRUE(t.find(0) == t.end()); + auto res = t.emplace(0); + EXPECT_TRUE(res.second); + EXPECT_EQ(1, t.size()); + t.clear(); + EXPECT_EQ(0, t.size()); + EXPECT_TRUE(t.find(0) == t.end()); +} + +TEST(Table, Swap) { + IntTable t; + EXPECT_TRUE(t.find(0) == t.end()); + auto res = t.emplace(0); + EXPECT_TRUE(res.second); + EXPECT_EQ(1, t.size()); + IntTable u; + t.swap(u); + EXPECT_EQ(0, t.size()); + EXPECT_EQ(1, u.size()); + EXPECT_TRUE(t.find(0) == t.end()); + EXPECT_THAT(*u.find(0), 0); +} + +TEST(Table, Rehash) { + IntTable t; + EXPECT_TRUE(t.find(0) == t.end()); + t.emplace(0); + t.emplace(1); + EXPECT_EQ(2, t.size()); + t.rehash(128); + EXPECT_EQ(2, t.size()); + EXPECT_THAT(*t.find(0), 0); + EXPECT_THAT(*t.find(1), 1); +} + +TEST(Table, RehashDoesNotRehashWhenNotNecessary) { + IntTable t; + t.emplace(0); + t.emplace(1); + auto* p = &*t.find(0); + t.rehash(1); + EXPECT_EQ(p, &*t.find(0)); +} + +TEST(Table, RehashZeroDoesNotAllocateOnEmptyTable) { + IntTable t; + t.rehash(0); + EXPECT_EQ(0, t.bucket_count()); +} + +TEST(Table, RehashZeroDeallocatesEmptyTable) { + IntTable t; + t.emplace(0); + t.clear(); + EXPECT_NE(0, t.bucket_count()); + t.rehash(0); + EXPECT_EQ(0, t.bucket_count()); +} + +TEST(Table, RehashZeroForcesRehash) { + IntTable t; + t.emplace(0); + t.emplace(1); + auto* p = &*t.find(0); + t.rehash(0); + EXPECT_NE(p, &*t.find(0)); +} + +TEST(Table, ConstructFromInitList) { + using P = std::pair<std::string, std::string>; + struct Q { + operator P() const { return {}; } + }; + StringTable t = {P(), Q(), {}, {{}, {}}}; +} + +TEST(Table, CopyConstruct) { + IntTable t; + t.max_load_factor(.321f); + t.emplace(0); + EXPECT_EQ(1, t.size()); + { + IntTable u(t); + EXPECT_EQ(1, u.size()); + EXPECT_EQ(t.max_load_factor(), u.max_load_factor()); + EXPECT_THAT(*u.find(0), 0); + } + { + IntTable u{t}; + EXPECT_EQ(1, u.size()); + EXPECT_EQ(t.max_load_factor(), u.max_load_factor()); + EXPECT_THAT(*u.find(0), 0); + } + { + IntTable u = t; + EXPECT_EQ(1, u.size()); + EXPECT_EQ(t.max_load_factor(), u.max_load_factor()); + EXPECT_THAT(*u.find(0), 0); + } +} + +TEST(Table, CopyConstructWithAlloc) { + StringTable t; + t.max_load_factor(.321f); + t.emplace("a", "b"); + EXPECT_EQ(1, t.size()); + StringTable u(t, Alloc<std::pair<std::string, std::string>>()); + EXPECT_EQ(1, u.size()); + EXPECT_EQ(t.max_load_factor(), u.max_load_factor()); + EXPECT_THAT(*u.find("a"), Pair("a", "b")); +} + +struct ExplicitAllocIntTable + : raw_hash_set<IntPolicy, container_internal::hash_default_hash<int64_t>, + std::equal_to<int64_t>, Alloc<int64_t>> { + ExplicitAllocIntTable() {} +}; + +TEST(Table, AllocWithExplicitCtor) { + ExplicitAllocIntTable t; + EXPECT_EQ(0, t.size()); +} + +TEST(Table, MoveConstruct) { + { + StringTable t; + t.max_load_factor(.321f); + const float lf = t.max_load_factor(); + t.emplace("a", "b"); + EXPECT_EQ(1, t.size()); + + StringTable u(std::move(t)); + EXPECT_EQ(1, u.size()); + EXPECT_EQ(lf, u.max_load_factor()); + EXPECT_THAT(*u.find("a"), Pair("a", "b")); + } + { + StringTable t; + t.max_load_factor(.321f); + const float lf = t.max_load_factor(); + t.emplace("a", "b"); + EXPECT_EQ(1, t.size()); + + StringTable u{std::move(t)}; + EXPECT_EQ(1, u.size()); + EXPECT_EQ(lf, u.max_load_factor()); + EXPECT_THAT(*u.find("a"), Pair("a", "b")); + } + { + StringTable t; + t.max_load_factor(.321f); + const float lf = t.max_load_factor(); + t.emplace("a", "b"); + EXPECT_EQ(1, t.size()); + + StringTable u = std::move(t); + EXPECT_EQ(1, u.size()); + EXPECT_EQ(lf, u.max_load_factor()); + EXPECT_THAT(*u.find("a"), Pair("a", "b")); + } +} + +TEST(Table, MoveConstructWithAlloc) { + StringTable t; + t.max_load_factor(.321f); + const float lf = t.max_load_factor(); + t.emplace("a", "b"); + EXPECT_EQ(1, t.size()); + StringTable u(std::move(t), Alloc<std::pair<std::string, std::string>>()); + EXPECT_EQ(1, u.size()); + EXPECT_EQ(lf, u.max_load_factor()); + EXPECT_THAT(*u.find("a"), Pair("a", "b")); +} + +TEST(Table, CopyAssign) { + StringTable t; + t.max_load_factor(.321f); + t.emplace("a", "b"); + EXPECT_EQ(1, t.size()); + StringTable u; + u = t; + EXPECT_EQ(1, u.size()); + EXPECT_EQ(t.max_load_factor(), u.max_load_factor()); + EXPECT_THAT(*u.find("a"), Pair("a", "b")); +} + +TEST(Table, CopySelfAssign) { + StringTable t; + t.max_load_factor(.321f); + const float lf = t.max_load_factor(); + t.emplace("a", "b"); + EXPECT_EQ(1, t.size()); + t = *&t; + EXPECT_EQ(1, t.size()); + EXPECT_EQ(lf, t.max_load_factor()); + EXPECT_THAT(*t.find("a"), Pair("a", "b")); +} + +TEST(Table, MoveAssign) { + StringTable t; + t.max_load_factor(.321f); + const float lf = t.max_load_factor(); + t.emplace("a", "b"); + EXPECT_EQ(1, t.size()); + StringTable u; + u = std::move(t); + EXPECT_EQ(1, u.size()); + EXPECT_EQ(lf, u.max_load_factor()); + EXPECT_THAT(*u.find("a"), Pair("a", "b")); +} + +TEST(Table, Equality) { + StringTable t; + std::vector<std::pair<std::string, std::string>> v = {{"a", "b"}, {"aa", "bb"}}; + t.insert(std::begin(v), std::end(v)); + StringTable u = t; + EXPECT_EQ(u, t); +} + +TEST(Table, Equality2) { + StringTable t; + std::vector<std::pair<std::string, std::string>> v1 = {{"a", "b"}, {"aa", "bb"}}; + t.insert(std::begin(v1), std::end(v1)); + StringTable u; + std::vector<std::pair<std::string, std::string>> v2 = {{"a", "a"}, {"aa", "aa"}}; + u.insert(std::begin(v2), std::end(v2)); + EXPECT_NE(u, t); +} + +TEST(Table, Equality3) { + StringTable t; + std::vector<std::pair<std::string, std::string>> v1 = {{"b", "b"}, {"bb", "bb"}}; + t.insert(std::begin(v1), std::end(v1)); + StringTable u; + std::vector<std::pair<std::string, std::string>> v2 = {{"a", "a"}, {"aa", "aa"}}; + u.insert(std::begin(v2), std::end(v2)); + EXPECT_NE(u, t); +} + +TEST(Table, NumDeletedRegression) { + IntTable t; + t.emplace(0); + t.erase(t.find(0)); + // construct over a deleted slot. + t.emplace(0); + t.clear(); +} + +TEST(Table, FindFullDeletedRegression) { + IntTable t; + for (int i = 0; i < 1000; ++i) { + t.emplace(i); + t.erase(t.find(i)); + } + EXPECT_EQ(0, t.size()); +} + +TEST(Table, ReplacingDeletedSlotDoesNotRehash) { + size_t n; + { + // Compute n such that n is the maximum number of elements before rehash. + IntTable t; + t.emplace(0); + size_t c = t.bucket_count(); + for (n = 1; c == t.bucket_count(); ++n) t.emplace(n); + --n; + } + IntTable t; + t.rehash(n); + const size_t c = t.bucket_count(); + for (size_t i = 0; i != n; ++i) t.emplace(i); + EXPECT_EQ(c, t.bucket_count()) << "rehashing threshold = " << n; + t.erase(0); + t.emplace(0); + EXPECT_EQ(c, t.bucket_count()) << "rehashing threshold = " << n; +} + +TEST(Table, NoThrowMoveConstruct) { + ASSERT_TRUE( + std::is_nothrow_copy_constructible<absl::Hash<absl::string_view>>::value); + ASSERT_TRUE(std::is_nothrow_copy_constructible< + std::equal_to<absl::string_view>>::value); + ASSERT_TRUE(std::is_nothrow_copy_constructible<std::allocator<int>>::value); + EXPECT_TRUE(std::is_nothrow_move_constructible<StringTable>::value); +} + +TEST(Table, NoThrowMoveAssign) { + ASSERT_TRUE( + std::is_nothrow_move_assignable<absl::Hash<absl::string_view>>::value); + ASSERT_TRUE( + std::is_nothrow_move_assignable<std::equal_to<absl::string_view>>::value); + ASSERT_TRUE(std::is_nothrow_move_assignable<std::allocator<int>>::value); + ASSERT_TRUE( + absl::allocator_traits<std::allocator<int>>::is_always_equal::value); + EXPECT_TRUE(std::is_nothrow_move_assignable<StringTable>::value); +} + +TEST(Table, NoThrowSwappable) { + ASSERT_TRUE( + container_internal::IsNoThrowSwappable<absl::Hash<absl::string_view>>()); + ASSERT_TRUE(container_internal::IsNoThrowSwappable< + std::equal_to<absl::string_view>>()); + ASSERT_TRUE(container_internal::IsNoThrowSwappable<std::allocator<int>>()); + EXPECT_TRUE(container_internal::IsNoThrowSwappable<StringTable>()); +} + +TEST(Table, HeterogeneousLookup) { + struct Hash { + size_t operator()(int64_t i) const { return i; } + size_t operator()(double i) const { + ADD_FAILURE(); + return i; + } + }; + struct Eq { + bool operator()(int64_t a, int64_t b) const { return a == b; } + bool operator()(double a, int64_t b) const { + ADD_FAILURE(); + return a == b; + } + bool operator()(int64_t a, double b) const { + ADD_FAILURE(); + return a == b; + } + bool operator()(double a, double b) const { + ADD_FAILURE(); + return a == b; + } + }; + + struct THash { + using is_transparent = void; + size_t operator()(int64_t i) const { return i; } + size_t operator()(double i) const { return i; } + }; + struct TEq { + using is_transparent = void; + bool operator()(int64_t a, int64_t b) const { return a == b; } + bool operator()(double a, int64_t b) const { return a == b; } + bool operator()(int64_t a, double b) const { return a == b; } + bool operator()(double a, double b) const { return a == b; } + }; + + raw_hash_set<IntPolicy, Hash, Eq, Alloc<int64_t>> s{0, 1, 2}; + // It will convert to int64_t before the query. + EXPECT_EQ(1, *s.find(double{1.1})); + + raw_hash_set<IntPolicy, THash, TEq, Alloc<int64_t>> ts{0, 1, 2}; + // It will try to use the double, and fail to find the object. + EXPECT_TRUE(ts.find(1.1) == ts.end()); +} + +template <class Table> +using CallFind = decltype(std::declval<Table&>().find(17)); + +template <class Table> +using CallErase = decltype(std::declval<Table&>().erase(17)); + +template <class Table> +using CallExtract = decltype(std::declval<Table&>().extract(17)); + +template <class Table> +using CallPrefetch = decltype(std::declval<Table&>().prefetch(17)); + +template <class Table> +using CallCount = decltype(std::declval<Table&>().count(17)); + +template <template <typename> class C, class Table, class = void> +struct VerifyResultOf : std::false_type {}; + +template <template <typename> class C, class Table> +struct VerifyResultOf<C, Table, absl::void_t<C<Table>>> : std::true_type {}; + +TEST(Table, HeterogeneousLookupOverloads) { + using NonTransparentTable = + raw_hash_set<StringPolicy, absl::Hash<absl::string_view>, + std::equal_to<absl::string_view>, std::allocator<int>>; + + EXPECT_FALSE((VerifyResultOf<CallFind, NonTransparentTable>())); + EXPECT_FALSE((VerifyResultOf<CallErase, NonTransparentTable>())); + EXPECT_FALSE((VerifyResultOf<CallExtract, NonTransparentTable>())); + EXPECT_FALSE((VerifyResultOf<CallPrefetch, NonTransparentTable>())); + EXPECT_FALSE((VerifyResultOf<CallCount, NonTransparentTable>())); + + using TransparentTable = raw_hash_set< + StringPolicy, + absl::container_internal::hash_default_hash<absl::string_view>, + absl::container_internal::hash_default_eq<absl::string_view>, + std::allocator<int>>; + + EXPECT_TRUE((VerifyResultOf<CallFind, TransparentTable>())); + EXPECT_TRUE((VerifyResultOf<CallErase, TransparentTable>())); + EXPECT_TRUE((VerifyResultOf<CallExtract, TransparentTable>())); + EXPECT_TRUE((VerifyResultOf<CallPrefetch, TransparentTable>())); + EXPECT_TRUE((VerifyResultOf<CallCount, TransparentTable>())); +} + +// TODO(alkis): Expand iterator tests. +TEST(Iterator, IsDefaultConstructible) { + StringTable::iterator i; + EXPECT_TRUE(i == StringTable::iterator()); +} + +TEST(ConstIterator, IsDefaultConstructible) { + StringTable::const_iterator i; + EXPECT_TRUE(i == StringTable::const_iterator()); +} + +TEST(Iterator, ConvertsToConstIterator) { + StringTable::iterator i; + EXPECT_TRUE(i == StringTable::const_iterator()); +} + +TEST(Iterator, Iterates) { + IntTable t; + for (size_t i = 3; i != 6; ++i) EXPECT_TRUE(t.emplace(i).second); + EXPECT_THAT(t, UnorderedElementsAre(3, 4, 5)); +} + +TEST(Table, Merge) { + StringTable t1, t2; + t1.emplace("0", "-0"); + t1.emplace("1", "-1"); + t2.emplace("0", "~0"); + t2.emplace("2", "~2"); + + EXPECT_THAT(t1, UnorderedElementsAre(Pair("0", "-0"), Pair("1", "-1"))); + EXPECT_THAT(t2, UnorderedElementsAre(Pair("0", "~0"), Pair("2", "~2"))); + + t1.merge(t2); + EXPECT_THAT(t1, UnorderedElementsAre(Pair("0", "-0"), Pair("1", "-1"), + Pair("2", "~2"))); + EXPECT_THAT(t2, UnorderedElementsAre(Pair("0", "~0"))); +} + +TEST(Nodes, EmptyNodeType) { + using node_type = StringTable::node_type; + node_type n; + EXPECT_FALSE(n); + EXPECT_TRUE(n.empty()); + + EXPECT_TRUE((std::is_same<node_type::allocator_type, + StringTable::allocator_type>::value)); +} + +TEST(Nodes, ExtractInsert) { + constexpr char k0[] = "Very long std::string zero."; + constexpr char k1[] = "Very long std::string one."; + constexpr char k2[] = "Very long std::string two."; + StringTable t = {{k0, ""}, {k1, ""}, {k2, ""}}; + EXPECT_THAT(t, + UnorderedElementsAre(Pair(k0, ""), Pair(k1, ""), Pair(k2, ""))); + + auto node = t.extract(k0); + EXPECT_THAT(t, UnorderedElementsAre(Pair(k1, ""), Pair(k2, ""))); + EXPECT_TRUE(node); + EXPECT_FALSE(node.empty()); + + StringTable t2; + auto res = t2.insert(std::move(node)); + EXPECT_TRUE(res.inserted); + EXPECT_THAT(*res.position, Pair(k0, "")); + EXPECT_FALSE(res.node); + EXPECT_THAT(t2, UnorderedElementsAre(Pair(k0, ""))); + + // Not there. + EXPECT_THAT(t, UnorderedElementsAre(Pair(k1, ""), Pair(k2, ""))); + node = t.extract("Not there!"); + EXPECT_THAT(t, UnorderedElementsAre(Pair(k1, ""), Pair(k2, ""))); + EXPECT_FALSE(node); + + // Inserting nothing. + res = t2.insert(std::move(node)); + EXPECT_FALSE(res.inserted); + EXPECT_EQ(res.position, t2.end()); + EXPECT_FALSE(res.node); + EXPECT_THAT(t2, UnorderedElementsAre(Pair(k0, ""))); + + t.emplace(k0, "1"); + node = t.extract(k0); + + // Insert duplicate. + res = t2.insert(std::move(node)); + EXPECT_FALSE(res.inserted); + EXPECT_THAT(*res.position, Pair(k0, "")); + EXPECT_TRUE(res.node); + EXPECT_FALSE(node); +} + +StringTable MakeSimpleTable(size_t size) { + StringTable t; + for (size_t i = 0; i < size; ++i) t.emplace(std::string(1, 'A' + i), ""); + return t; +} + +std::string OrderOfIteration(const StringTable& t) { + std::string order; + for (auto& p : t) order += p.first; + return order; +} + +TEST(Table, IterationOrderChangesByInstance) { + // Needs to be more than kWidth elements to be able to affect order. + const StringTable reference = MakeSimpleTable(20); + + // Since order is non-deterministic we can't just try once and verify. + // We'll try until we find that order changed. It should not take many tries + // for that. + // Important: we have to keep the old tables around. Otherwise tcmalloc will + // just give us the same blocks and we would be doing the same order again. + std::vector<StringTable> garbage; + for (int i = 0; i < 10; ++i) { + auto trial = MakeSimpleTable(20); + if (OrderOfIteration(trial) != OrderOfIteration(reference)) { + // We are done. + return; + } + garbage.push_back(std::move(trial)); + } + FAIL(); +} + +TEST(Table, IterationOrderChangesOnRehash) { + // Since order is non-deterministic we can't just try once and verify. + // We'll try until we find that order changed. It should not take many tries + // for that. + // Important: we have to keep the old tables around. Otherwise tcmalloc will + // just give us the same blocks and we would be doing the same order again. + std::vector<StringTable> garbage; + for (int i = 0; i < 10; ++i) { + // Needs to be more than kWidth elements to be able to affect order. + StringTable t = MakeSimpleTable(20); + const std::string reference = OrderOfIteration(t); + // Force rehash to the same size. + t.rehash(0); + std::string trial = OrderOfIteration(t); + if (trial != reference) { + // We are done. + return; + } + garbage.push_back(std::move(t)); + } + FAIL(); +} + +TEST(Table, IterationOrderChangesForSmallTables) { + // Since order is non-deterministic we can't just try once and verify. + // We'll try until we find that order changed. + // Important: we have to keep the old tables around. Otherwise tcmalloc will + // just give us the same blocks and we would be doing the same order again. + StringTable reference_table = MakeSimpleTable(5); + const std::string reference = OrderOfIteration(reference_table); + std::vector<StringTable> garbage; + for (int i = 0; i < 50; ++i) { + StringTable t = MakeSimpleTable(5); + std::string trial = OrderOfIteration(t); + if (trial != reference) { + // We are done. + return; + } + garbage.push_back(std::move(t)); + } + FAIL() << "Iteration order remained the same across many attempts."; +} + +// Fill the table to 3 different load factors (min, median, max) and evaluate +// the percentage of perfect hits using the debug API. +template <class Table, class AddFn> +std::vector<double> CollectPerfectRatios(Table t, AddFn add) { + using Key = typename Table::key_type; + + // First, fill enough to have a good distribution. + constexpr size_t kMinSize = 10000; + std::vector<Key> keys; + while (t.size() < kMinSize) keys.push_back(add(t)); + // Then, insert until we reach min load factor. + double lf = t.load_factor(); + while (lf <= t.load_factor()) keys.push_back(add(t)); + + // We are now at min load factor. Take a snapshot. + size_t perfect = 0; + auto update_perfect = [&](Key k) { + perfect += GetHashtableDebugNumProbes(t, k) == 0; + }; + for (const auto& k : keys) update_perfect(k); + + std::vector<double> perfect_ratios; + // Keep going until we hit max load factor. + while (t.load_factor() < .6) { + perfect_ratios.push_back(1.0 * perfect / t.size()); + update_perfect(add(t)); + } + while (t.load_factor() > .5) { + perfect_ratios.push_back(1.0 * perfect / t.size()); + update_perfect(add(t)); + } + return perfect_ratios; +} + +std::vector<std::pair<double, double>> StringTablePefectRatios() { + constexpr bool kRandomizesInserts = +#if NDEBUG + false; +#else // NDEBUG + true; +#endif // NDEBUG + + // The effective load factor is larger in non-opt mode because we insert + // elements out of order. + switch (container_internal::Group::kWidth) { + case 8: + if (kRandomizesInserts) { + return {{0.986, 0.02}, {0.95, 0.02}, {0.89, 0.02}}; + } else { + return {{0.995, 0.01}, {0.97, 0.01}, {0.89, 0.02}}; + } + break; + case 16: + if (kRandomizesInserts) { + return {{0.973, 0.01}, {0.965, 0.01}, {0.92, 0.02}}; + } else { + return {{0.995, 0.005}, {0.99, 0.005}, {0.94, 0.01}}; + } + break; + default: + // Ignore anything else. + return {}; + } +} + +// This is almost a change detector, but it allows us to know how we are +// affecting the probe distribution. +TEST(Table, EffectiveLoadFactorStrings) { + std::vector<double> perfect_ratios = + CollectPerfectRatios(StringTable(), [](StringTable& t) { + return t.emplace(std::to_string(t.size()), "").first->first; + }); + + auto ratios = StringTablePefectRatios(); + if (ratios.empty()) return; + + EXPECT_THAT(perfect_ratios.front(), + DoubleNear(ratios[0].first, ratios[0].second)); + EXPECT_THAT(perfect_ratios[perfect_ratios.size() / 2], + DoubleNear(ratios[1].first, ratios[1].second)); + EXPECT_THAT(perfect_ratios.back(), + DoubleNear(ratios[2].first, ratios[2].second)); +} + +std::vector<std::pair<double, double>> IntTablePefectRatios() { + constexpr bool kRandomizesInserts = +#ifdef NDEBUG + false; +#else // NDEBUG + true; +#endif // NDEBUG + + // The effective load factor is larger in non-opt mode because we insert + // elements out of order. + switch (container_internal::Group::kWidth) { + case 8: + if (kRandomizesInserts) { + return {{0.99, 0.02}, {0.985, 0.02}, {0.95, 0.05}}; + } else { + return {{0.99, 0.01}, {0.99, 0.01}, {0.95, 0.02}}; + } + break; + case 16: + if (kRandomizesInserts) { + return {{0.98, 0.02}, {0.978, 0.02}, {0.96, 0.02}}; + } else { + return {{0.998, 0.003}, {0.995, 0.01}, {0.975, 0.02}}; + } + break; + default: + // Ignore anything else. + return {}; + } +} + +// This is almost a change detector, but it allows us to know how we are +// affecting the probe distribution. +TEST(Table, EffectiveLoadFactorInts) { + std::vector<double> perfect_ratios = CollectPerfectRatios( + IntTable(), [](IntTable& t) { return *t.emplace(t.size()).first; }); + + auto ratios = IntTablePefectRatios(); + if (ratios.empty()) return; + + EXPECT_THAT(perfect_ratios.front(), + DoubleNear(ratios[0].first, ratios[0].second)); + EXPECT_THAT(perfect_ratios[perfect_ratios.size() / 2], + DoubleNear(ratios[1].first, ratios[1].second)); + EXPECT_THAT(perfect_ratios.back(), + DoubleNear(ratios[2].first, ratios[2].second)); +} + +// Confirm that we assert if we try to erase() end(). +TEST(Table, EraseOfEndAsserts) { + // Use an assert with side-effects to figure out if they are actually enabled. + bool assert_enabled = false; + assert([&]() { + assert_enabled = true; + return true; + }()); + if (!assert_enabled) return; + + IntTable t; + // Extra simple "regexp" as regexp support is highly varied across platforms. + constexpr char kDeathMsg[] = "it != end"; + EXPECT_DEATH(t.erase(t.end()), kDeathMsg); +} + +#ifdef ADDRESS_SANITIZER +TEST(Sanitizer, PoisoningUnused) { + IntTable t; + // Insert something to force an allocation. + int64_t& v1 = *t.insert(0).first; + + // Make sure there is something to test. + ASSERT_GT(t.capacity(), 1); + + int64_t* slots = RawHashSetTestOnlyAccess::GetSlots(t); + for (size_t i = 0; i < t.capacity(); ++i) { + EXPECT_EQ(slots + i != &v1, __asan_address_is_poisoned(slots + i)); + } +} + +TEST(Sanitizer, PoisoningOnErase) { + IntTable t; + int64_t& v = *t.insert(0).first; + + EXPECT_FALSE(__asan_address_is_poisoned(&v)); + t.erase(0); + EXPECT_TRUE(__asan_address_is_poisoned(&v)); +} +#endif // ADDRESS_SANITIZER + +} // namespace +} // namespace container_internal +} // namespace absl |