tvl-depot/absl/container/internal/raw_hash_set_test.cc
Abseil Team a00bdd176d Export of internal Abseil changes.
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fa894a667a3bebbe479539c8d5e829beebf36c27 by Abseil Team <absl-team@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 216855907

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59e0a42fa9045eb164573b82ce625248bd9999f3 by Jon Cohen <cohenjon@google.com>:

Some edits to the documentation for absl::Hash as I was reading through it.

Itemized changes:
  * implement -> implements for grammar
  * Fix an incomplete sentence
  * specify *any* type T as opposed to *a* type T ? this is just the language I tend to see for these sorts of concepts in math and makes it more clear that we?re talking about a set of all types T satisfying these constraints
  * add arguments to comine() and combine_contiguous() ? this was mostly because for hash_continuous there was a reference to `size` elements without any mention of what `size` was.

PiperOrigin-RevId: 216766923

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c2a744d0f70ec5a079c22502b7a7ca72805a29dc by Shaindel Schwartz <shaindel@google.com>:

Remove unneeded include.

PiperOrigin-RevId: 216703710

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ad22fc4e3d236f7bd354b61e0fa37ea524a7cf5e by Shaindel Schwartz <shaindel@google.com>:

Fix typos.

PiperOrigin-RevId: 216699071
GitOrigin-RevId: fa894a667a3bebbe479539c8d5e829beebf36c27
Change-Id: I35c8d8be66043aad9f17bbb867e69acb770bd1b0
2018-10-12 10:26:45 -04:00

1949 lines
58 KiB
C++

// 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 fill up to 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}}};
}
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}}};
}
}
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}}};
}
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}}};
}
}
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}};
}
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}};
}
}
ABSL_RAW_LOG(FATAL, "%s", "Unknown Group width");
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}};
}
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}};
}
}
ABSL_RAW_LOG(FATAL, "%s", "Unknown Group width");
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(TableDeathTest, 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_IF_SUPPORTED(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