diff options
Diffstat (limited to 'absl/container/internal')
28 files changed, 2564 insertions, 1563 deletions
diff --git a/absl/container/internal/btree.h b/absl/container/internal/btree.h index 0bb38366..01f4e749 100644 --- a/absl/container/internal/btree.h +++ b/absl/container/internal/btree.h @@ -58,6 +58,7 @@ #include <type_traits> #include <utility> +#include "absl/base/internal/raw_logging.h" #include "absl/base/macros.h" #include "absl/container/internal/common.h" #include "absl/container/internal/compressed_tuple.h" @@ -74,12 +75,24 @@ namespace absl { ABSL_NAMESPACE_BEGIN namespace container_internal { +#ifdef ABSL_BTREE_ENABLE_GENERATIONS +#error ABSL_BTREE_ENABLE_GENERATIONS cannot be directly set +#elif defined(ABSL_HAVE_ADDRESS_SANITIZER) || \ + defined(ABSL_HAVE_MEMORY_SANITIZER) +// When compiled in sanitizer mode, we add generation integers to the nodes and +// iterators. When iterators are used, we validate that the container has not +// been mutated since the iterator was constructed. +#define ABSL_BTREE_ENABLE_GENERATIONS +#endif + +template <typename Compare, typename T, typename U> +using compare_result_t = absl::result_of_t<const Compare(const T &, const U &)>; + // A helper class that indicates if the Compare parameter is a key-compare-to // comparator. template <typename Compare, typename T> using btree_is_key_compare_to = - std::is_convertible<absl::result_of_t<Compare(const T &, const T &)>, - absl::weak_ordering>; + std::is_convertible<compare_result_t<Compare, T, T>, absl::weak_ordering>; struct StringBtreeDefaultLess { using is_transparent = void; @@ -88,7 +101,12 @@ struct StringBtreeDefaultLess { // Compatibility constructor. StringBtreeDefaultLess(std::less<std::string>) {} // NOLINT - StringBtreeDefaultLess(std::less<string_view>) {} // NOLINT + StringBtreeDefaultLess(std::less<absl::string_view>) {} // NOLINT + + // Allow converting to std::less for use in key_comp()/value_comp(). + explicit operator std::less<std::string>() const { return {}; } + explicit operator std::less<absl::string_view>() const { return {}; } + explicit operator std::less<absl::Cord>() const { return {}; } absl::weak_ordering operator()(absl::string_view lhs, absl::string_view rhs) const { @@ -115,7 +133,12 @@ struct StringBtreeDefaultGreater { StringBtreeDefaultGreater() = default; StringBtreeDefaultGreater(std::greater<std::string>) {} // NOLINT - StringBtreeDefaultGreater(std::greater<string_view>) {} // NOLINT + StringBtreeDefaultGreater(std::greater<absl::string_view>) {} // NOLINT + + // Allow converting to std::greater for use in key_comp()/value_comp(). + explicit operator std::greater<std::string>() const { return {}; } + explicit operator std::greater<absl::string_view>() const { return {}; } + explicit operator std::greater<absl::Cord>() const { return {}; } absl::weak_ordering operator()(absl::string_view lhs, absl::string_view rhs) const { @@ -136,49 +159,140 @@ struct StringBtreeDefaultGreater { } }; -// A helper class to convert a boolean comparison into a three-way "compare-to" -// comparison that returns an `absl::weak_ordering`. This helper -// class is specialized for less<std::string>, greater<std::string>, -// less<string_view>, greater<string_view>, less<absl::Cord>, and -// greater<absl::Cord>. -// -// key_compare_to_adapter is provided so that btree users -// automatically get the more efficient compare-to code when using common -// Abseil string types with common comparison functors. -// These string-like specializations also turn on heterogeneous lookup by -// default. +// See below comments for checked_compare. +template <typename Compare, bool is_class = std::is_class<Compare>::value> +struct checked_compare_base : Compare { + using Compare::Compare; + explicit checked_compare_base(Compare c) : Compare(std::move(c)) {} + const Compare &comp() const { return *this; } +}; template <typename Compare> -struct key_compare_to_adapter { - using type = Compare; +struct checked_compare_base<Compare, false> { + explicit checked_compare_base(Compare c) : compare(std::move(c)) {} + const Compare &comp() const { return compare; } + Compare compare; +}; + +// A mechanism for opting out of checked_compare for use only in btree_test.cc. +struct BtreeTestOnlyCheckedCompareOptOutBase {}; + +// A helper class to adapt the specified comparator for two use cases: +// (1) When using common Abseil string types with common comparison functors, +// convert a boolean comparison into a three-way comparison that returns an +// `absl::weak_ordering`. This helper class is specialized for +// less<std::string>, greater<std::string>, less<string_view>, +// greater<string_view>, less<absl::Cord>, and greater<absl::Cord>. +// (2) Adapt the comparator to diagnose cases of non-strict-weak-ordering (see +// https://en.cppreference.com/w/cpp/named_req/Compare) in debug mode. Whenever +// a comparison is made, we will make assertions to verify that the comparator +// is valid. +template <typename Compare, typename Key> +struct key_compare_adapter { + // Inherit from checked_compare_base to support function pointers and also + // keep empty-base-optimization (EBO) support for classes. + // Note: we can't use CompressedTuple here because that would interfere + // with the EBO for `btree::rightmost_`. `btree::rightmost_` is itself a + // CompressedTuple and nested `CompressedTuple`s don't support EBO. + // TODO(b/214288561): use CompressedTuple instead once it supports EBO for + // nested `CompressedTuple`s. + struct checked_compare : checked_compare_base<Compare> { + private: + using Base = typename checked_compare::checked_compare_base; + using Base::comp; + + // If possible, returns whether `t` is equivalent to itself. We can only do + // this for `Key`s because we can't be sure that it's safe to call + // `comp()(k, k)` otherwise. Even if SFINAE allows it, there could be a + // compilation failure inside the implementation of the comparison operator. + bool is_self_equivalent(const Key &k) const { + // Note: this works for both boolean and three-way comparators. + return comp()(k, k) == 0; + } + // If we can't compare `t` with itself, returns true unconditionally. + template <typename T> + bool is_self_equivalent(const T &) const { + return true; + } + + public: + using Base::Base; + checked_compare(Compare comp) : Base(std::move(comp)) {} // NOLINT + + // Allow converting to Compare for use in key_comp()/value_comp(). + explicit operator Compare() const { return comp(); } + + template <typename T, typename U, + absl::enable_if_t< + std::is_same<bool, compare_result_t<Compare, T, U>>::value, + int> = 0> + bool operator()(const T &lhs, const U &rhs) const { + // NOTE: if any of these assertions fail, then the comparator does not + // establish a strict-weak-ordering (see + // https://en.cppreference.com/w/cpp/named_req/Compare). + assert(is_self_equivalent(lhs)); + assert(is_self_equivalent(rhs)); + const bool lhs_comp_rhs = comp()(lhs, rhs); + assert(!lhs_comp_rhs || !comp()(rhs, lhs)); + return lhs_comp_rhs; + } + + template < + typename T, typename U, + absl::enable_if_t<std::is_convertible<compare_result_t<Compare, T, U>, + absl::weak_ordering>::value, + int> = 0> + absl::weak_ordering operator()(const T &lhs, const U &rhs) const { + // NOTE: if any of these assertions fail, then the comparator does not + // establish a strict-weak-ordering (see + // https://en.cppreference.com/w/cpp/named_req/Compare). + assert(is_self_equivalent(lhs)); + assert(is_self_equivalent(rhs)); + const absl::weak_ordering lhs_comp_rhs = comp()(lhs, rhs); +#ifndef NDEBUG + const absl::weak_ordering rhs_comp_lhs = comp()(rhs, lhs); + if (lhs_comp_rhs > 0) { + assert(rhs_comp_lhs < 0 && "lhs_comp_rhs > 0 -> rhs_comp_lhs < 0"); + } else if (lhs_comp_rhs == 0) { + assert(rhs_comp_lhs == 0 && "lhs_comp_rhs == 0 -> rhs_comp_lhs == 0"); + } else { + assert(rhs_comp_lhs > 0 && "lhs_comp_rhs < 0 -> rhs_comp_lhs > 0"); + } +#endif + return lhs_comp_rhs; + } + }; + using type = absl::conditional_t< + std::is_base_of<BtreeTestOnlyCheckedCompareOptOutBase, Compare>::value, + Compare, checked_compare>; }; template <> -struct key_compare_to_adapter<std::less<std::string>> { +struct key_compare_adapter<std::less<std::string>, std::string> { using type = StringBtreeDefaultLess; }; template <> -struct key_compare_to_adapter<std::greater<std::string>> { +struct key_compare_adapter<std::greater<std::string>, std::string> { using type = StringBtreeDefaultGreater; }; template <> -struct key_compare_to_adapter<std::less<absl::string_view>> { +struct key_compare_adapter<std::less<absl::string_view>, absl::string_view> { using type = StringBtreeDefaultLess; }; template <> -struct key_compare_to_adapter<std::greater<absl::string_view>> { +struct key_compare_adapter<std::greater<absl::string_view>, absl::string_view> { using type = StringBtreeDefaultGreater; }; template <> -struct key_compare_to_adapter<std::less<absl::Cord>> { +struct key_compare_adapter<std::less<absl::Cord>, absl::Cord> { using type = StringBtreeDefaultLess; }; template <> -struct key_compare_to_adapter<std::greater<absl::Cord>> { +struct key_compare_adapter<std::greater<absl::Cord>, absl::Cord> { using type = StringBtreeDefaultGreater; }; @@ -214,19 +328,70 @@ struct prefers_linear_node_search< T, absl::void_t<typename T::absl_btree_prefer_linear_node_search>> : T::absl_btree_prefer_linear_node_search {}; +template <typename Compare, typename Key> +constexpr bool compare_has_valid_result_type() { + using compare_result_type = compare_result_t<Compare, Key, Key>; + return std::is_same<compare_result_type, bool>::value || + std::is_convertible<compare_result_type, absl::weak_ordering>::value; +} + +template <typename original_key_compare, typename value_type> +class map_value_compare { + template <typename Params> + friend class btree; + + // Note: this `protected` is part of the API of std::map::value_compare. See + // https://en.cppreference.com/w/cpp/container/map/value_compare. + protected: + explicit map_value_compare(original_key_compare c) : comp(std::move(c)) {} + + original_key_compare comp; // NOLINT + + public: + auto operator()(const value_type &lhs, const value_type &rhs) const + -> decltype(comp(lhs.first, rhs.first)) { + return comp(lhs.first, rhs.first); + } +}; + template <typename Key, typename Compare, typename Alloc, int TargetNodeSize, - bool Multi, typename SlotPolicy> + bool IsMulti, bool IsMap, typename SlotPolicy> struct common_params { + using original_key_compare = Compare; + // If Compare is a common comparator for a string-like type, then we adapt it // to use heterogeneous lookup and to be a key-compare-to comparator. - using key_compare = typename key_compare_to_adapter<Compare>::type; + // We also adapt the comparator to diagnose invalid comparators in debug mode. + // We disable this when `Compare` is invalid in a way that will cause + // adaptation to fail (having invalid return type) so that we can give a + // better compilation failure in static_assert_validation. If we don't do + // this, then there will be cascading compilation failures that are confusing + // for users. + using key_compare = + absl::conditional_t<!compare_has_valid_result_type<Compare, Key>(), + Compare, + typename key_compare_adapter<Compare, Key>::type>; + + static constexpr bool kIsKeyCompareStringAdapted = + std::is_same<key_compare, StringBtreeDefaultLess>::value || + std::is_same<key_compare, StringBtreeDefaultGreater>::value; + static constexpr bool kIsKeyCompareTransparent = + IsTransparent<original_key_compare>::value || + kIsKeyCompareStringAdapted; + static constexpr bool kEnableGenerations = +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + true; +#else + false; +#endif + // A type which indicates if we have a key-compare-to functor or a plain old // key-compare functor. using is_key_compare_to = btree_is_key_compare_to<key_compare, Key>; using allocator_type = Alloc; using key_type = Key; - using size_type = std::make_signed<size_t>::type; + using size_type = size_t; using difference_type = ptrdiff_t; using slot_policy = SlotPolicy; @@ -238,6 +403,12 @@ struct common_params { using reference = value_type &; using const_reference = const value_type &; + using value_compare = + absl::conditional_t<IsMap, + map_value_compare<original_key_compare, value_type>, + original_key_compare>; + using is_map_container = std::integral_constant<bool, IsMap>; + // For the given lookup key type, returns whether we can have multiple // equivalent keys in the btree. If this is a multi-container, then we can. // Otherwise, we can have multiple equivalent keys only if all of the @@ -248,27 +419,25 @@ struct common_params { // that we know has the same equivalence classes for all lookup types. template <typename LookupKey> constexpr static bool can_have_multiple_equivalent_keys() { - return Multi || - (IsTransparent<key_compare>::value && - !std::is_same<LookupKey, Key>::value && - !std::is_same<key_compare, StringBtreeDefaultLess>::value && - !std::is_same<key_compare, StringBtreeDefaultGreater>::value); + return IsMulti || (IsTransparent<key_compare>::value && + !std::is_same<LookupKey, Key>::value && + !kIsKeyCompareStringAdapted); } enum { kTargetNodeSize = TargetNodeSize, - // Upper bound for the available space for values. This is largest for leaf + // Upper bound for the available space for slots. This is largest for leaf // nodes, which have overhead of at least a pointer + 4 bytes (for storing // 3 field_types and an enum). - kNodeValueSpace = + kNodeSlotSpace = TargetNodeSize - /*minimum overhead=*/(sizeof(void *) + 4), }; - // This is an integral type large enough to hold as many - // ValueSize-values as will fit a node of TargetNodeSize bytes. + // This is an integral type large enough to hold as many slots as will fit a + // node of TargetNodeSize bytes. using node_count_type = - absl::conditional_t<(kNodeValueSpace / sizeof(value_type) > + absl::conditional_t<(kNodeSlotSpace / sizeof(slot_type) > (std::numeric_limits<uint8_t>::max)()), uint16_t, uint8_t>; // NOLINT @@ -291,116 +460,10 @@ struct common_params { slot_policy::destroy(alloc, slot); } static void transfer(Alloc *alloc, slot_type *new_slot, slot_type *old_slot) { - construct(alloc, new_slot, old_slot); - destroy(alloc, old_slot); - } - static void swap(Alloc *alloc, slot_type *a, slot_type *b) { - slot_policy::swap(alloc, a, b); - } - static void move(Alloc *alloc, slot_type *src, slot_type *dest) { - slot_policy::move(alloc, src, dest); - } -}; - -// A parameters structure for holding the type parameters for a btree_map. -// Compare and Alloc should be nothrow copy-constructible. -template <typename Key, typename Data, typename Compare, typename Alloc, - int TargetNodeSize, bool Multi> -struct map_params : common_params<Key, Compare, Alloc, TargetNodeSize, Multi, - map_slot_policy<Key, Data>> { - using super_type = typename map_params::common_params; - using mapped_type = Data; - // This type allows us to move keys when it is safe to do so. It is safe - // for maps in which value_type and mutable_value_type are layout compatible. - using slot_policy = typename super_type::slot_policy; - using slot_type = typename super_type::slot_type; - using value_type = typename super_type::value_type; - using init_type = typename super_type::init_type; - - using key_compare = typename super_type::key_compare; - // Inherit from key_compare for empty base class optimization. - struct value_compare : private key_compare { - value_compare() = default; - explicit value_compare(const key_compare &cmp) : key_compare(cmp) {} - - template <typename T, typename U> - auto operator()(const T &left, const U &right) const - -> decltype(std::declval<key_compare>()(left.first, right.first)) { - return key_compare::operator()(left.first, right.first); - } - }; - using is_map_container = std::true_type; - - template <typename V> - static auto key(const V &value) -> decltype(value.first) { - return value.first; - } - static const Key &key(const slot_type *s) { return slot_policy::key(s); } - static const Key &key(slot_type *s) { return slot_policy::key(s); } - // For use in node handle. - static auto mutable_key(slot_type *s) - -> decltype(slot_policy::mutable_key(s)) { - return slot_policy::mutable_key(s); - } - static mapped_type &value(value_type *value) { return value->second; } -}; - -// This type implements the necessary functions from the -// absl::container_internal::slot_type interface. -template <typename Key> -struct set_slot_policy { - using slot_type = Key; - using value_type = Key; - using mutable_value_type = Key; - - static value_type &element(slot_type *slot) { return *slot; } - static const value_type &element(const slot_type *slot) { return *slot; } - - template <typename Alloc, class... Args> - static void construct(Alloc *alloc, slot_type *slot, Args &&... args) { - absl::allocator_traits<Alloc>::construct(*alloc, slot, - std::forward<Args>(args)...); - } - - template <typename Alloc> - static void construct(Alloc *alloc, slot_type *slot, slot_type *other) { - absl::allocator_traits<Alloc>::construct(*alloc, slot, std::move(*other)); - } - - template <typename Alloc> - static void destroy(Alloc *alloc, slot_type *slot) { - absl::allocator_traits<Alloc>::destroy(*alloc, slot); - } - - template <typename Alloc> - static void swap(Alloc * /*alloc*/, slot_type *a, slot_type *b) { - using std::swap; - swap(*a, *b); - } - - template <typename Alloc> - static void move(Alloc * /*alloc*/, slot_type *src, slot_type *dest) { - *dest = std::move(*src); + slot_policy::transfer(alloc, new_slot, old_slot); } }; -// A parameters structure for holding the type parameters for a btree_set. -// Compare and Alloc should be nothrow copy-constructible. -template <typename Key, typename Compare, typename Alloc, int TargetNodeSize, - bool Multi> -struct set_params : common_params<Key, Compare, Alloc, TargetNodeSize, Multi, - set_slot_policy<Key>> { - using value_type = Key; - using slot_type = typename set_params::common_params::slot_type; - using value_compare = typename set_params::common_params::key_compare; - using is_map_container = std::false_type; - - template <typename V> - static const V &key(const V &value) { return value; } - static const Key &key(const slot_type *slot) { return *slot; } - static const Key &key(slot_type *slot) { return *slot; } -}; - // An adapter class that converts a lower-bound compare into an upper-bound // compare. Note: there is no need to make a version of this adapter specialized // for key-compare-to functors because the upper-bound (the first value greater @@ -435,8 +498,8 @@ struct SearchResult { template <typename V> struct SearchResult<V, false> { SearchResult() {} - explicit SearchResult(V value) : value(value) {} - SearchResult(V value, MatchKind /*match*/) : value(value) {} + explicit SearchResult(V v) : value(v) {} + SearchResult(V v, MatchKind /*match*/) : value(v) {} V value; @@ -453,6 +516,7 @@ class btree_node { using field_type = typename Params::node_count_type; using allocator_type = typename Params::allocator_type; using slot_type = typename Params::slot_type; + using original_key_compare = typename Params::original_key_compare; public: using params_type = Params; @@ -474,21 +538,28 @@ class btree_node { // - Otherwise, choose binary. // TODO(ezb): Might make sense to add condition(s) based on node-size. using use_linear_search = std::integral_constant< - bool, - has_linear_node_search_preference<key_compare>::value - ? prefers_linear_node_search<key_compare>::value - : has_linear_node_search_preference<key_type>::value + bool, has_linear_node_search_preference<original_key_compare>::value + ? prefers_linear_node_search<original_key_compare>::value + : has_linear_node_search_preference<key_type>::value ? prefers_linear_node_search<key_type>::value : std::is_arithmetic<key_type>::value && - (std::is_same<std::less<key_type>, key_compare>::value || + (std::is_same<std::less<key_type>, + original_key_compare>::value || std::is_same<std::greater<key_type>, - key_compare>::value)>; + original_key_compare>::value)>; - // This class is organized by gtl::Layout as if it had the following - // structure: + // This class is organized by absl::container_internal::Layout as if it had + // the following structure: // // A pointer to the node's parent. // btree_node *parent; // + // // When ABSL_BTREE_ENABLE_GENERATIONS is defined, we also have a + // // generation integer in order to check that when iterators are + // // used, they haven't been invalidated already. Only the generation on + // // the root is used, but we have one on each node because whether a node + // // is root or not can change. + // uint32_t generation; + // // // The position of the node in the node's parent. // field_type position; // // The index of the first populated value in `values`. @@ -535,23 +606,27 @@ class btree_node { btree_node() = default; private: - using layout_type = absl::container_internal::Layout<btree_node *, field_type, - slot_type, btree_node *>; + using layout_type = + absl::container_internal::Layout<btree_node *, uint32_t, field_type, + slot_type, btree_node *>; constexpr static size_type SizeWithNSlots(size_type n) { - return layout_type(/*parent*/ 1, - /*position, start, finish, max_count*/ 4, - /*slots*/ n, - /*children*/ 0) + return layout_type( + /*parent*/ 1, + /*generation*/ params_type::kEnableGenerations ? 1 : 0, + /*position, start, finish, max_count*/ 4, + /*slots*/ n, + /*children*/ 0) .AllocSize(); } - // A lower bound for the overhead of fields other than values in a leaf node. + // A lower bound for the overhead of fields other than slots in a leaf node. constexpr static size_type MinimumOverhead() { - return SizeWithNSlots(1) - sizeof(value_type); + return SizeWithNSlots(1) - sizeof(slot_type); } // Compute how many values we can fit onto a leaf node taking into account // padding. - constexpr static size_type NodeTargetSlots(const int begin, const int end) { + constexpr static size_type NodeTargetSlots(const size_type begin, + const size_type end) { return begin == end ? begin : SizeWithNSlots((begin + end) / 2 + 1) > params_type::kTargetNodeSize @@ -580,16 +655,20 @@ class btree_node { // Leaves can have less than kNodeSlots values. constexpr static layout_type LeafLayout(const int slot_count = kNodeSlots) { - return layout_type(/*parent*/ 1, - /*position, start, finish, max_count*/ 4, - /*slots*/ slot_count, - /*children*/ 0); + return layout_type( + /*parent*/ 1, + /*generation*/ params_type::kEnableGenerations ? 1 : 0, + /*position, start, finish, max_count*/ 4, + /*slots*/ slot_count, + /*children*/ 0); } constexpr static layout_type InternalLayout() { - return layout_type(/*parent*/ 1, - /*position, start, finish, max_count*/ 4, - /*slots*/ kNodeSlots, - /*children*/ kNodeSlots + 1); + return layout_type( + /*parent*/ 1, + /*generation*/ params_type::kEnableGenerations ? 1 : 0, + /*position, start, finish, max_count*/ 4, + /*slots*/ kNodeSlots, + /*children*/ kNodeSlots + 1); } constexpr static size_type LeafSize(const int slot_count = kNodeSlots) { return LeafLayout(slot_count).AllocSize(); @@ -603,44 +682,47 @@ class btree_node { template <size_type N> inline typename layout_type::template ElementType<N> *GetField() { // We assert that we don't read from values that aren't there. - assert(N < 3 || !leaf()); + assert(N < 4 || is_internal()); return InternalLayout().template Pointer<N>(reinterpret_cast<char *>(this)); } template <size_type N> inline const typename layout_type::template ElementType<N> *GetField() const { - assert(N < 3 || !leaf()); + assert(N < 4 || is_internal()); return InternalLayout().template Pointer<N>( reinterpret_cast<const char *>(this)); } void set_parent(btree_node *p) { *GetField<0>() = p; } - field_type &mutable_finish() { return GetField<1>()[2]; } - slot_type *slot(int i) { return &GetField<2>()[i]; } + field_type &mutable_finish() { return GetField<2>()[2]; } + slot_type *slot(int i) { return &GetField<3>()[i]; } slot_type *start_slot() { return slot(start()); } slot_type *finish_slot() { return slot(finish()); } - const slot_type *slot(int i) const { return &GetField<2>()[i]; } - void set_position(field_type v) { GetField<1>()[0] = v; } - void set_start(field_type v) { GetField<1>()[1] = v; } - void set_finish(field_type v) { GetField<1>()[2] = v; } + const slot_type *slot(int i) const { return &GetField<3>()[i]; } + void set_position(field_type v) { GetField<2>()[0] = v; } + void set_start(field_type v) { GetField<2>()[1] = v; } + void set_finish(field_type v) { GetField<2>()[2] = v; } // This method is only called by the node init methods. - void set_max_count(field_type v) { GetField<1>()[3] = v; } + void set_max_count(field_type v) { GetField<2>()[3] = v; } public: // Whether this is a leaf node or not. This value doesn't change after the // node is created. - bool leaf() const { return GetField<1>()[3] != kInternalNodeMaxCount; } + bool is_leaf() const { return GetField<2>()[3] != kInternalNodeMaxCount; } + // Whether this is an internal node or not. This value doesn't change after + // the node is created. + bool is_internal() const { return !is_leaf(); } // Getter for the position of this node in its parent. - field_type position() const { return GetField<1>()[0]; } + field_type position() const { return GetField<2>()[0]; } // Getter for the offset of the first value in the `values` array. field_type start() const { - // TODO(ezb): when floating storage is implemented, return GetField<1>()[1]; - assert(GetField<1>()[1] == 0); + // TODO(ezb): when floating storage is implemented, return GetField<2>()[1]; + assert(GetField<2>()[1] == 0); return 0; } // Getter for the offset after the last value in the `values` array. - field_type finish() const { return GetField<1>()[2]; } + field_type finish() const { return GetField<2>()[2]; } // Getters for the number of values stored in this node. field_type count() const { @@ -650,7 +732,7 @@ class btree_node { field_type max_count() const { // Internal nodes have max_count==kInternalNodeMaxCount. // Leaf nodes have max_count in [1, kNodeSlots]. - const field_type max_count = GetField<1>()[3]; + const field_type max_count = GetField<2>()[3]; return max_count == field_type{kInternalNodeMaxCount} ? field_type{kNodeSlots} : max_count; @@ -661,21 +743,44 @@ class btree_node { // Getter for whether the node is the root of the tree. The parent of the // root of the tree is the leftmost node in the tree which is guaranteed to // be a leaf. - bool is_root() const { return parent()->leaf(); } + bool is_root() const { return parent()->is_leaf(); } void make_root() { assert(parent()->is_root()); + set_generation(parent()->generation()); set_parent(parent()->parent()); } + // Gets the root node's generation integer, which is the one used by the tree. + uint32_t *get_root_generation() const { + assert(params_type::kEnableGenerations); + const btree_node *curr = this; + for (; !curr->is_root(); curr = curr->parent()) continue; + return const_cast<uint32_t *>(&curr->GetField<1>()[0]); + } + + // Returns the generation for iterator validation. + uint32_t generation() const { + return params_type::kEnableGenerations ? *get_root_generation() : 0; + } + // Updates generation. Should only be called on a root node or during node + // initialization. + void set_generation(uint32_t generation) { + if (params_type::kEnableGenerations) GetField<1>()[0] = generation; + } + // Updates the generation. We do this whenever the node is mutated. + void next_generation() { + if (params_type::kEnableGenerations) ++*get_root_generation(); + } + // Getters for the key/value at position i in the node. const key_type &key(int i) const { return params_type::key(slot(i)); } reference value(int i) { return params_type::element(slot(i)); } const_reference value(int i) const { return params_type::element(slot(i)); } // Getters/setter for the child at position i in the node. - btree_node *child(int i) const { return GetField<3>()[i]; } + btree_node *child(int i) const { return GetField<4>()[i]; } btree_node *start_child() const { return child(start()); } - btree_node *&mutable_child(int i) { return GetField<3>()[i]; } + btree_node *&mutable_child(int i) { return GetField<4>()[i]; } void clear_child(int i) { absl::container_internal::SanitizerPoisonObject(&mutable_child(i)); } @@ -832,7 +937,8 @@ class btree_node { void merge(btree_node *src, allocator_type *alloc); // Node allocation/deletion routines. - void init_leaf(btree_node *parent, int max_count) { + void init_leaf(int max_count, btree_node *parent) { + set_generation(0); set_parent(parent); set_position(0); set_start(0); @@ -842,7 +948,7 @@ class btree_node { start_slot(), max_count * sizeof(slot_type)); } void init_internal(btree_node *parent) { - init_leaf(parent, kNodeSlots); + init_leaf(kNodeSlots, parent); // Set `max_count` to a sentinel value to indicate that this node is // internal. set_max_count(kInternalNodeMaxCount); @@ -861,15 +967,18 @@ class btree_node { private: template <typename... Args> void value_init(const field_type i, allocator_type *alloc, Args &&... args) { + next_generation(); absl::container_internal::SanitizerUnpoisonObject(slot(i)); params_type::construct(alloc, slot(i), std::forward<Args>(args)...); } void value_destroy(const field_type i, allocator_type *alloc) { + next_generation(); params_type::destroy(alloc, slot(i)); absl::container_internal::SanitizerPoisonObject(slot(i)); } void value_destroy_n(const field_type i, const field_type n, allocator_type *alloc) { + next_generation(); for (slot_type *s = slot(i), *end = slot(i + n); s != end; ++s) { params_type::destroy(alloc, s); absl::container_internal::SanitizerPoisonObject(s); @@ -885,6 +994,7 @@ class btree_node { // Transfers value from slot `src_i` in `src_node` to slot `dest_i` in `this`. void transfer(const size_type dest_i, const size_type src_i, btree_node *src_node, allocator_type *alloc) { + next_generation(); transfer(slot(dest_i), src_node->slot(src_i), alloc); } @@ -893,6 +1003,7 @@ class btree_node { void transfer_n(const size_type n, const size_type dest_i, const size_type src_i, btree_node *src_node, allocator_type *alloc) { + next_generation(); for (slot_type *src = src_node->slot(src_i), *end = src + n, *dest = slot(dest_i); src != end; ++src, ++dest) { @@ -905,6 +1016,7 @@ class btree_node { void transfer_n_backward(const size_type n, const size_type dest_i, const size_type src_i, btree_node *src_node, allocator_type *alloc) { + next_generation(); for (slot_type *src = src_node->slot(src_i + n - 1), *end = src - n, *dest = slot(dest_i + n - 1); src != end; --src, --dest) { @@ -915,13 +1027,13 @@ class btree_node { template <typename P> friend class btree; template <typename N, typename R, typename P> - friend struct btree_iterator; + friend class btree_iterator; friend class BtreeNodePeer; + friend struct btree_access; }; template <typename Node, typename Reference, typename Pointer> -struct btree_iterator { - private: +class btree_iterator { using key_type = typename Node::key_type; using size_type = typename Node::size_type; using params_type = typename Node::params_type; @@ -949,9 +1061,15 @@ struct btree_iterator { using reference = Reference; using iterator_category = std::bidirectional_iterator_tag; - btree_iterator() : node(nullptr), position(-1) {} - explicit btree_iterator(Node *n) : node(n), position(n->start()) {} - btree_iterator(Node *n, int p) : node(n), position(p) {} + btree_iterator() : btree_iterator(nullptr, -1) {} + explicit btree_iterator(Node *n) : btree_iterator(n, n->start()) {} + btree_iterator(Node *n, int p) : node_(n), position_(p) { +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + // Use `~uint32_t{}` as a sentinel value for iterator generations so it + // doesn't match the initial value for the actual generation. + generation_ = n != nullptr ? n->generation() : ~uint32_t{}; +#endif + } // NOTE: this SFINAE allows for implicit conversions from iterator to // const_iterator, but it specifically avoids hiding the copy constructor so @@ -962,58 +1080,32 @@ struct btree_iterator { std::is_same<btree_iterator, const_iterator>::value, int> = 0> btree_iterator(const btree_iterator<N, R, P> other) // NOLINT - : node(other.node), position(other.position) {} - - private: - // This SFINAE allows explicit conversions from const_iterator to - // iterator, but also avoids hiding the copy constructor. - // NOTE: the const_cast is safe because this constructor is only called by - // non-const methods and the container owns the nodes. - template <typename N, typename R, typename P, - absl::enable_if_t< - std::is_same<btree_iterator<N, R, P>, const_iterator>::value && - std::is_same<btree_iterator, iterator>::value, - int> = 0> - explicit btree_iterator(const btree_iterator<N, R, P> other) - : node(const_cast<node_type *>(other.node)), position(other.position) {} - - // Increment/decrement the iterator. - void increment() { - if (node->leaf() && ++position < node->finish()) { - return; - } - increment_slow(); - } - void increment_slow(); - - void decrement() { - if (node->leaf() && --position >= node->start()) { - return; - } - decrement_slow(); + : node_(other.node_), position_(other.position_) { +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + generation_ = other.generation_; +#endif } - void decrement_slow(); - public: bool operator==(const iterator &other) const { - return node == other.node && position == other.position; + return node_ == other.node_ && position_ == other.position_; } bool operator==(const const_iterator &other) const { - return node == other.node && position == other.position; + return node_ == other.node_ && position_ == other.position_; } bool operator!=(const iterator &other) const { - return node != other.node || position != other.position; + return node_ != other.node_ || position_ != other.position_; } bool operator!=(const const_iterator &other) const { - return node != other.node || position != other.position; + return node_ != other.node_ || position_ != other.position_; } // Accessors for the key/value the iterator is pointing at. reference operator*() const { - ABSL_HARDENING_ASSERT(node != nullptr); - ABSL_HARDENING_ASSERT(node->start() <= position); - ABSL_HARDENING_ASSERT(node->finish() > position); - return node->value(position); + ABSL_HARDENING_ASSERT(node_ != nullptr); + ABSL_HARDENING_ASSERT(node_->start() <= position_); + ABSL_HARDENING_ASSERT(node_->finish() > position_); + assert_valid_generation(); + return node_->value(position_); } pointer operator->() const { return &operator*(); } @@ -1051,23 +1143,84 @@ struct btree_iterator { friend class btree_multiset_container; template <typename TreeType, typename CheckerType> friend class base_checker; + friend struct btree_access; - const key_type &key() const { return node->key(position); } - slot_type *slot() { return node->slot(position); } + // This SFINAE allows explicit conversions from const_iterator to + // iterator, but also avoids hiding the copy constructor. + // NOTE: the const_cast is safe because this constructor is only called by + // non-const methods and the container owns the nodes. + template <typename N, typename R, typename P, + absl::enable_if_t< + std::is_same<btree_iterator<N, R, P>, const_iterator>::value && + std::is_same<btree_iterator, iterator>::value, + int> = 0> + explicit btree_iterator(const btree_iterator<N, R, P> other) + : node_(const_cast<node_type *>(other.node_)), + position_(other.position_) { +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + generation_ = other.generation_; +#endif + } + + // Increment/decrement the iterator. + void increment() { + assert_valid_generation(); + if (node_->is_leaf() && ++position_ < node_->finish()) { + return; + } + increment_slow(); + } + void increment_slow(); + + void decrement() { + assert_valid_generation(); + if (node_->is_leaf() && --position_ >= node_->start()) { + return; + } + decrement_slow(); + } + void decrement_slow(); + + // Updates the generation. For use internally right before we return an + // iterator to the user. + void update_generation() { +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + if (node_ != nullptr) generation_ = node_->generation(); +#endif + } + + const key_type &key() const { return node_->key(position_); } + decltype(std::declval<Node *>()->slot(0)) slot() { + return node_->slot(position_); + } + + void assert_valid_generation() const { +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + if (node_ != nullptr && node_->generation() != generation_) { + ABSL_INTERNAL_LOG( + FATAL, + "Attempting to use an invalidated iterator. The corresponding b-tree " + "container has been mutated since this iterator was constructed."); + } +#endif + } // The node in the tree the iterator is pointing at. - Node *node; + Node *node_; // The position within the node of the tree the iterator is pointing at. // NOTE: this is an int rather than a field_type because iterators can point // to invalid positions (such as -1) in certain circumstances. - int position; + int position_; +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + // Used to check that the iterator hasn't been invalidated. + uint32_t generation_; +#endif }; template <typename Params> class btree { using node_type = btree_node<Params>; using is_key_compare_to = typename Params::is_key_compare_to; - using init_type = typename Params::init_type; using field_type = typename node_type::field_type; // We use a static empty node for the root/leftmost/rightmost of empty btrees @@ -1075,6 +1228,9 @@ class btree { struct alignas(node_type::Alignment()) EmptyNodeType : node_type { using field_type = typename node_type::field_type; node_type *parent; +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + uint32_t generation = 0; +#endif field_type position = 0; field_type start = 0; field_type finish = 0; @@ -1129,6 +1285,7 @@ class btree { using size_type = typename Params::size_type; using difference_type = typename Params::difference_type; using key_compare = typename Params::key_compare; + using original_key_compare = typename Params::original_key_compare; using value_compare = typename Params::value_compare; using allocator_type = typename Params::allocator_type; using reference = typename Params::reference; @@ -1147,14 +1304,6 @@ class btree { using slot_type = typename Params::slot_type; private: - // For use in copy_or_move_values_in_order. - const value_type &maybe_move_from_iterator(const_iterator it) { return *it; } - value_type &&maybe_move_from_iterator(iterator it) { - // This is a destructive operation on the other container so it's safe for - // us to const_cast and move from the keys here even if it's a set. - return std::move(const_cast<value_type &>(*it)); - } - // Copies or moves (depending on the template parameter) the values in // other into this btree in their order in other. This btree must be empty // before this method is called. This method is used in copy construction, @@ -1167,7 +1316,7 @@ class btree { public: btree(const key_compare &comp, const allocator_type &alloc) - : root_(comp, alloc, EmptyNode()), rightmost_(EmptyNode()), size_(0) {} + : root_(EmptyNode()), rightmost_(comp, alloc, EmptyNode()), size_(0) {} btree(const btree &other) : btree(other, other.allocator()) {} btree(const btree &other, const allocator_type &alloc) @@ -1175,10 +1324,10 @@ class btree { copy_or_move_values_in_order(other); } btree(btree &&other) noexcept - : root_(std::move(other.root_)), - rightmost_(absl::exchange(other.rightmost_, EmptyNode())), + : root_(absl::exchange(other.root_, EmptyNode())), + rightmost_(std::move(other.rightmost_)), size_(absl::exchange(other.size_, 0)) { - other.mutable_root() = EmptyNode(); + other.mutable_rightmost() = EmptyNode(); } btree(btree &&other, const allocator_type &alloc) : btree(other.key_comp(), alloc) { @@ -1203,9 +1352,9 @@ class btree { iterator begin() { return iterator(leftmost()); } const_iterator begin() const { return const_iterator(leftmost()); } - iterator end() { return iterator(rightmost_, rightmost_->finish()); } + iterator end() { return iterator(rightmost(), rightmost()->finish()); } const_iterator end() const { - return const_iterator(rightmost_, rightmost_->finish()); + return const_iterator(rightmost(), rightmost()->finish()); } reverse_iterator rbegin() { return reverse_iterator(end()); } const_reverse_iterator rbegin() const { @@ -1331,14 +1480,16 @@ class btree { void swap(btree &other); const key_compare &key_comp() const noexcept { - return root_.template get<0>(); + return rightmost_.template get<0>(); } template <typename K1, typename K2> bool compare_keys(const K1 &a, const K2 &b) const { return compare_internal::compare_result_as_less_than(key_comp()(a, b)); } - value_compare value_comp() const { return value_compare(key_comp()); } + value_compare value_comp() const { + return value_compare(original_key_compare(key_comp())); + } // Verifies the structure of the btree. void verify() const; @@ -1376,6 +1527,7 @@ class btree { } // The total number of bytes used by the btree. + // TODO(b/169338300): update to support node_btree_*. size_type bytes_used() const { node_stats stats = internal_stats(root()); if (stats.leaf_nodes == 1 && stats.internal_nodes == 0) { @@ -1419,11 +1571,20 @@ class btree { allocator_type get_allocator() const { return allocator(); } private: + friend struct btree_access; + // Internal accessor routines. - node_type *root() { return root_.template get<2>(); } - const node_type *root() const { return root_.template get<2>(); } - node_type *&mutable_root() noexcept { return root_.template get<2>(); } - key_compare *mutable_key_comp() noexcept { return &root_.template get<0>(); } + node_type *root() { return root_; } + const node_type *root() const { return root_; } + node_type *&mutable_root() noexcept { return root_; } + node_type *rightmost() { return rightmost_.template get<2>(); } + const node_type *rightmost() const { return rightmost_.template get<2>(); } + node_type *&mutable_rightmost() noexcept { + return rightmost_.template get<2>(); + } + key_compare *mutable_key_comp() noexcept { + return &rightmost_.template get<0>(); + } // The leftmost node is stored as the parent of the root node. node_type *leftmost() { return root()->parent(); } @@ -1431,10 +1592,10 @@ class btree { // Allocator routines. allocator_type *mutable_allocator() noexcept { - return &root_.template get<1>(); + return &rightmost_.template get<1>(); } const allocator_type &allocator() const noexcept { - return root_.template get<1>(); + return rightmost_.template get<1>(); } // Allocates a correctly aligned node of at least size bytes using the @@ -1453,12 +1614,12 @@ class btree { } node_type *new_leaf_node(node_type *parent) { node_type *n = allocate(node_type::LeafSize()); - n->init_leaf(parent, kNodeSlots); + n->init_leaf(kNodeSlots, parent); return n; } node_type *new_leaf_root_node(const int max_count) { node_type *n = allocate(node_type::LeafSize(max_count)); - n->init_leaf(/*parent=*/n, max_count); + n->init_leaf(max_count, /*parent=*/n); return n; } @@ -1482,10 +1643,10 @@ class btree { void try_shrink(); iterator internal_end(iterator iter) { - return iter.node != nullptr ? iter : end(); + return iter.node_ != nullptr ? iter : end(); } const_iterator internal_end(const_iterator iter) const { - return iter.node != nullptr ? iter : end(); + return iter.node_ != nullptr ? iter : end(); } // Emplaces a value into the btree immediately before iter. Requires that @@ -1495,9 +1656,8 @@ class btree { // Returns an iterator pointing to the first value >= the value "iter" is // pointing at. Note that "iter" might be pointing to an invalid location such - // as iter.position == iter.node->finish(). This routine simply moves iter up - // in the tree to a valid location. - // Requires: iter.node is non-null. + // as iter.position_ == iter.node_->finish(). This routine simply moves iter + // up in the tree to a valid location. Requires: iter.node_ is non-null. template <typename IterType> static IterType internal_last(IterType iter); @@ -1533,7 +1693,7 @@ class btree { if (node == nullptr || (node == root() && empty())) { return node_stats(0, 0); } - if (node->leaf()) { + if (node->is_leaf()) { return node_stats(1, 0); } node_stats res(0, 1); @@ -1543,15 +1703,14 @@ class btree { return res; } - // We use compressed tuple in order to save space because key_compare and - // allocator_type are usually empty. - absl::container_internal::CompressedTuple<key_compare, allocator_type, - node_type *> - root_; + node_type *root_; // A pointer to the rightmost node. Note that the leftmost node is stored as - // the root's parent. - node_type *rightmost_; + // the root's parent. We use compressed tuple in order to save space because + // key_compare and allocator_type are usually empty. + absl::container_internal::CompressedTuple<key_compare, allocator_type, + node_type *> + rightmost_; // Number of values. size_type size_; @@ -1575,8 +1734,8 @@ inline void btree_node<P>::emplace_value(const size_type i, value_init(i, alloc, std::forward<Args>(args)...); set_finish(finish() + 1); - if (!leaf() && finish() > i + 1) { - for (int j = finish(); j > i + 1; --j) { + if (is_internal() && finish() > i + 1) { + for (field_type j = finish(); j > i + 1; --j) { set_child(j, child(j - 1)); } clear_child(i + 1); @@ -1593,7 +1752,7 @@ inline void btree_node<P>::remove_values(const field_type i, const field_type src_i = i + to_erase; transfer_n(orig_finish - src_i, i, src_i, this, alloc); - if (!leaf()) { + if (is_internal()) { // Delete all children between begin and end. for (int j = 0; j < to_erase; ++j) { clear_and_delete(child(i + j + 1), alloc); @@ -1630,7 +1789,7 @@ void btree_node<P>::rebalance_right_to_left(const int to_move, right->transfer_n(right->count() - to_move, right->start(), right->start() + to_move, right, alloc); - if (!leaf()) { + if (is_internal()) { // Move the child pointers from the right to the left node. for (int i = 0; i < to_move; ++i) { init_child(finish() + i + 1, right->child(i)); @@ -1677,7 +1836,7 @@ void btree_node<P>::rebalance_left_to_right(const int to_move, // 4) Move the new delimiting value to the parent from the left node. parent()->transfer(position(), finish() - to_move, this, alloc); - if (!leaf()) { + if (is_internal()) { // Move the child pointers from the left to the right node. for (int i = right->finish(); i >= right->start(); --i) { right->init_child(i + to_move, right->child(i)); @@ -1723,7 +1882,7 @@ void btree_node<P>::split(const int insert_position, btree_node *dest, value_destroy(finish(), alloc); parent()->init_child(position() + 1, dest); - if (!leaf()) { + if (is_internal()) { for (int i = dest->start(), j = finish() + 1; i <= dest->finish(); ++i, ++j) { assert(child(j) != nullptr); @@ -1744,7 +1903,7 @@ void btree_node<P>::merge(btree_node *src, allocator_type *alloc) { // Move the values from the right to the left node. transfer_n(src->count(), finish() + 1, src->start(), src, alloc); - if (!leaf()) { + if (is_internal()) { // Move the child pointers from the right to the left node. for (int i = src->start(), j = finish() + 1; i <= src->finish(); ++i, ++j) { init_child(j, src->child(i)); @@ -1762,7 +1921,7 @@ void btree_node<P>::merge(btree_node *src, allocator_type *alloc) { template <typename P> void btree_node<P>::clear_and_delete(btree_node *node, allocator_type *alloc) { - if (node->leaf()) { + if (node->is_leaf()) { node->value_destroy_n(node->start(), node->count(), alloc); deallocate(LeafSize(node->max_count()), node, alloc); return; @@ -1776,7 +1935,15 @@ void btree_node<P>::clear_and_delete(btree_node *node, allocator_type *alloc) { btree_node *delete_root_parent = node->parent(); // Navigate to the leftmost leaf under node, and then delete upwards. - while (!node->leaf()) node = node->start_child(); + while (node->is_internal()) node = node->start_child(); +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + // When generations are enabled, we delete the leftmost leaf last in case it's + // the parent of the root and we need to check whether it's a leaf before we + // can update the root's generation. + // TODO(ezb): if we change btree_node::is_root to check a bool inside the node + // instead of checking whether the parent is a leaf, we can remove this logic. + btree_node *leftmost_leaf = node; +#endif // Use `int` because `pos` needs to be able to hold `kNodeSlots+1`, which // isn't guaranteed to be a valid `field_type`. int pos = node->position(); @@ -1786,14 +1953,17 @@ void btree_node<P>::clear_and_delete(btree_node *node, allocator_type *alloc) { assert(pos <= parent->finish()); do { node = parent->child(pos); - if (!node->leaf()) { + if (node->is_internal()) { // Navigate to the leftmost leaf under node. - while (!node->leaf()) node = node->start_child(); + while (node->is_internal()) node = node->start_child(); pos = node->position(); parent = node->parent(); } node->value_destroy_n(node->start(), node->count(), alloc); - deallocate(LeafSize(node->max_count()), node, alloc); +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + if (leftmost_leaf != node) +#endif + deallocate(LeafSize(node->max_count()), node, alloc); ++pos; } while (pos <= parent->finish()); @@ -1805,7 +1975,12 @@ void btree_node<P>::clear_and_delete(btree_node *node, allocator_type *alloc) { parent = node->parent(); node->value_destroy_n(node->start(), node->count(), alloc); deallocate(InternalSize(), node, alloc); - if (parent == delete_root_parent) return; + if (parent == delete_root_parent) { +#ifdef ABSL_BTREE_ENABLE_GENERATIONS + deallocate(LeafSize(leftmost_leaf->max_count()), leftmost_leaf, alloc); +#endif + return; + } ++pos; } while (pos > parent->finish()); } @@ -1815,49 +1990,49 @@ void btree_node<P>::clear_and_delete(btree_node *node, allocator_type *alloc) { // btree_iterator methods template <typename N, typename R, typename P> void btree_iterator<N, R, P>::increment_slow() { - if (node->leaf()) { - assert(position >= node->finish()); + if (node_->is_leaf()) { + assert(position_ >= node_->finish()); btree_iterator save(*this); - while (position == node->finish() && !node->is_root()) { - assert(node->parent()->child(node->position()) == node); - position = node->position(); - node = node->parent(); + while (position_ == node_->finish() && !node_->is_root()) { + assert(node_->parent()->child(node_->position()) == node_); + position_ = node_->position(); + node_ = node_->parent(); } // TODO(ezb): assert we aren't incrementing end() instead of handling. - if (position == node->finish()) { + if (position_ == node_->finish()) { *this = save; } } else { - assert(position < node->finish()); - node = node->child(position + 1); - while (!node->leaf()) { - node = node->start_child(); + assert(position_ < node_->finish()); + node_ = node_->child(position_ + 1); + while (node_->is_internal()) { + node_ = node_->start_child(); } - position = node->start(); + position_ = node_->start(); } } template <typename N, typename R, typename P> void btree_iterator<N, R, P>::decrement_slow() { - if (node->leaf()) { - assert(position <= -1); + if (node_->is_leaf()) { + assert(position_ <= -1); btree_iterator save(*this); - while (position < node->start() && !node->is_root()) { - assert(node->parent()->child(node->position()) == node); - position = node->position() - 1; - node = node->parent(); + while (position_ < node_->start() && !node_->is_root()) { + assert(node_->parent()->child(node_->position()) == node_); + position_ = node_->position() - 1; + node_ = node_->parent(); } // TODO(ezb): assert we aren't decrementing begin() instead of handling. - if (position < node->start()) { + if (position_ < node_->start()) { *this = save; } } else { - assert(position >= node->start()); - node = node->child(position); - while (!node->leaf()) { - node = node->child(node->finish()); + assert(position_ >= node_->start()); + node_ = node_->child(position_); + while (node_->is_internal()) { + node_ = node_->child(node_->finish()); } - position = node->finish() - 1; + position_ = node_->finish() - 1; } } @@ -1875,12 +2050,12 @@ void btree<P>::copy_or_move_values_in_order(Btree &other) { // values is the same order we'll store them in. auto iter = other.begin(); if (iter == other.end()) return; - insert_multi(maybe_move_from_iterator(iter)); + insert_multi(iter.slot()); ++iter; for (; iter != other.end(); ++iter) { // If the btree is not empty, we can just insert the new value at the end // of the tree. - internal_emplace(end(), maybe_move_from_iterator(iter)); + internal_emplace(end(), iter.slot()); } } @@ -1900,15 +2075,12 @@ constexpr bool btree<P>::static_assert_validation() { "target node size too large"); // Verify that key_compare returns an absl::{weak,strong}_ordering or bool. - using compare_result_type = - absl::result_of_t<key_compare(key_type, key_type)>; static_assert( - std::is_same<compare_result_type, bool>::value || - std::is_convertible<compare_result_type, absl::weak_ordering>::value, + compare_has_valid_result_type<key_compare, key_type>(), "key comparison function must return absl::{weak,strong}_ordering or " "bool."); - // Test the assumption made in setting kNodeValueSpace. + // Test the assumption made in setting kNodeSlotSpace. static_assert(node_type::MinimumOverhead() >= sizeof(void *) + 4, "node space assumption incorrect"); @@ -1962,7 +2134,7 @@ template <typename K, typename... Args> auto btree<P>::insert_unique(const K &key, Args &&... args) -> std::pair<iterator, bool> { if (empty()) { - mutable_root() = rightmost_ = new_leaf_root_node(1); + mutable_root() = mutable_rightmost() = new_leaf_root_node(1); } SearchResult<iterator, is_key_compare_to::value> res = internal_locate(key); @@ -1975,7 +2147,7 @@ auto btree<P>::insert_unique(const K &key, Args &&... args) } } else { iterator last = internal_last(iter); - if (last.node && !compare_keys(key, last.key())) { + if (last.node_ && !compare_keys(key, last.key())) { // The key already exists in the tree, do nothing. return {last, false}; } @@ -2020,8 +2192,11 @@ template <typename P> template <typename InputIterator> void btree<P>::insert_iterator_unique(InputIterator b, InputIterator e, char) { for (; b != e; ++b) { - init_type value(*b); - insert_hint_unique(end(), params_type::key(value), std::move(value)); + // Use a node handle to manage a temp slot. + auto node_handle = + CommonAccess::Construct<node_handle_type>(get_allocator(), *b); + slot_type *slot = CommonAccess::GetSlot(node_handle); + insert_hint_unique(end(), params_type::key(slot), slot); } } @@ -2029,11 +2204,11 @@ template <typename P> template <typename ValueType> auto btree<P>::insert_multi(const key_type &key, ValueType &&v) -> iterator { if (empty()) { - mutable_root() = rightmost_ = new_leaf_root_node(1); + mutable_root() = mutable_rightmost() = new_leaf_root_node(1); } iterator iter = internal_upper_bound(key); - if (iter.node == nullptr) { + if (iter.node_ == nullptr) { iter = end(); } return internal_emplace(iter, std::forward<ValueType>(v)); @@ -2093,15 +2268,15 @@ auto btree<P>::operator=(btree &&other) noexcept -> btree & { using std::swap; if (absl::allocator_traits< allocator_type>::propagate_on_container_copy_assignment::value) { - // Note: `root_` also contains the allocator and the key comparator. swap(root_, other.root_); + // Note: `rightmost_` also contains the allocator and the key comparator. swap(rightmost_, other.rightmost_); swap(size_, other.size_); } else { if (allocator() == other.allocator()) { swap(mutable_root(), other.mutable_root()); swap(*mutable_key_comp(), *other.mutable_key_comp()); - swap(rightmost_, other.rightmost_); + swap(mutable_rightmost(), other.mutable_rightmost()); swap(size_, other.size_); } else { // We aren't allowed to propagate the allocator and the allocator is @@ -2119,22 +2294,29 @@ auto btree<P>::operator=(btree &&other) noexcept -> btree & { template <typename P> auto btree<P>::erase(iterator iter) -> iterator { - bool internal_delete = false; - if (!iter.node->leaf()) { - // Deletion of a value on an internal node. First, move the largest value - // from our left child here, then delete that position (in remove_values() - // below). We can get to the largest value from our left child by - // decrementing iter. + iter.node_->value_destroy(iter.position_, mutable_allocator()); + iter.update_generation(); + + const bool internal_delete = iter.node_->is_internal(); + if (internal_delete) { + // Deletion of a value on an internal node. First, transfer the largest + // value from our left child here, then erase/rebalance from that position. + // We can get to the largest value from our left child by decrementing iter. iterator internal_iter(iter); --iter; - assert(iter.node->leaf()); - params_type::move(mutable_allocator(), iter.node->slot(iter.position), - internal_iter.node->slot(internal_iter.position)); - internal_delete = true; - } - - // Delete the key from the leaf. - iter.node->remove_values(iter.position, /*to_erase=*/1, mutable_allocator()); + assert(iter.node_->is_leaf()); + internal_iter.node_->transfer(internal_iter.position_, iter.position_, + iter.node_, mutable_allocator()); + } else { + // Shift values after erased position in leaf. In the internal case, we + // don't need to do this because the leaf position is the end of the node. + const field_type transfer_from = iter.position_ + 1; + const field_type num_to_transfer = iter.node_->finish() - transfer_from; + iter.node_->transfer_n(num_to_transfer, iter.position_, transfer_from, + iter.node_, mutable_allocator()); + } + // Update node finish and container size. + iter.node_->set_finish(iter.node_->finish() - 1); --size_; // We want to return the next value after the one we just erased. If we @@ -2142,7 +2324,7 @@ auto btree<P>::erase(iterator iter) -> iterator { // value is ++(++iter). If we erased from a leaf node (internal_delete == // false) then the next value is ++iter. Note that ++iter may point to an // internal node and the value in the internal node may move to a leaf node - // (iter.node) when rebalancing is performed at the leaf level. + // (iter.node_) when rebalancing is performed at the leaf level. iterator res = rebalance_after_delete(iter); @@ -2159,14 +2341,14 @@ auto btree<P>::rebalance_after_delete(iterator iter) -> iterator { iterator res(iter); bool first_iteration = true; for (;;) { - if (iter.node == root()) { + if (iter.node_ == root()) { try_shrink(); if (empty()) { return end(); } break; } - if (iter.node->count() >= kMinNodeValues) { + if (iter.node_->count() >= kMinNodeValues) { break; } bool merged = try_merge_or_rebalance(&iter); @@ -2179,14 +2361,15 @@ auto btree<P>::rebalance_after_delete(iterator iter) -> iterator { if (!merged) { break; } - iter.position = iter.node->position(); - iter.node = iter.node->parent(); + iter.position_ = iter.node_->position(); + iter.node_ = iter.node_->parent(); } + res.update_generation(); // Adjust our return value. If we're pointing at the end of a node, advance // the iterator. - if (res.position == res.node->finish()) { - res.position = res.node->finish() - 1; + if (res.position_ == res.node_->finish()) { + res.position_ = res.node_->finish() - 1; ++res; } @@ -2203,33 +2386,36 @@ auto btree<P>::erase_range(iterator begin, iterator end) return {0, begin}; } - if (count == size_) { + if (static_cast<size_type>(count) == size_) { clear(); return {count, this->end()}; } - if (begin.node == end.node) { - assert(end.position > begin.position); - begin.node->remove_values(begin.position, end.position - begin.position, - mutable_allocator()); + if (begin.node_ == end.node_) { + assert(end.position_ > begin.position_); + begin.node_->remove_values(begin.position_, end.position_ - begin.position_, + mutable_allocator()); size_ -= count; return {count, rebalance_after_delete(begin)}; } const size_type target_size = size_ - count; while (size_ > target_size) { - if (begin.node->leaf()) { + if (begin.node_->is_leaf()) { const size_type remaining_to_erase = size_ - target_size; - const size_type remaining_in_node = begin.node->finish() - begin.position; + const size_type remaining_in_node = + begin.node_->finish() - begin.position_; const size_type to_erase = (std::min)(remaining_to_erase, remaining_in_node); - begin.node->remove_values(begin.position, to_erase, mutable_allocator()); + begin.node_->remove_values(begin.position_, to_erase, + mutable_allocator()); size_ -= to_erase; begin = rebalance_after_delete(begin); } else { begin = erase(begin); } } + begin.update_generation(); return {count, begin}; } @@ -2238,8 +2424,7 @@ void btree<P>::clear() { if (!empty()) { node_type::clear_and_delete(root(), mutable_allocator()); } - mutable_root() = EmptyNode(); - rightmost_ = EmptyNode(); + mutable_root() = mutable_rightmost() = EmptyNode(); size_ = 0; } @@ -2248,15 +2433,15 @@ void btree<P>::swap(btree &other) { using std::swap; if (absl::allocator_traits< allocator_type>::propagate_on_container_swap::value) { - // Note: `root_` also contains the allocator and the key comparator. - swap(root_, other.root_); + // Note: `rightmost_` also contains the allocator and the key comparator. + swap(rightmost_, other.rightmost_); } else { // It's undefined behavior if the allocators are unequal here. assert(allocator() == other.allocator()); - swap(mutable_root(), other.mutable_root()); + swap(mutable_rightmost(), other.mutable_rightmost()); swap(*mutable_key_comp(), *other.mutable_key_comp()); } - swap(rightmost_, other.rightmost_); + swap(mutable_root(), other.mutable_root()); swap(size_, other.size_); } @@ -2264,18 +2449,18 @@ template <typename P> void btree<P>::verify() const { assert(root() != nullptr); assert(leftmost() != nullptr); - assert(rightmost_ != nullptr); + assert(rightmost() != nullptr); assert(empty() || size() == internal_verify(root(), nullptr, nullptr)); - assert(leftmost() == (++const_iterator(root(), -1)).node); - assert(rightmost_ == (--const_iterator(root(), root()->finish())).node); - assert(leftmost()->leaf()); - assert(rightmost_->leaf()); + assert(leftmost() == (++const_iterator(root(), -1)).node_); + assert(rightmost() == (--const_iterator(root(), root()->finish())).node_); + assert(leftmost()->is_leaf()); + assert(rightmost()->is_leaf()); } template <typename P> void btree<P>::rebalance_or_split(iterator *iter) { - node_type *&node = iter->node; - int &insert_position = iter->position; + node_type *&node = iter->node_; + int &insert_position = iter->position_; assert(node->count() == node->max_count()); assert(kNodeSlots == node->max_count()); @@ -2350,19 +2535,20 @@ void btree<P>::rebalance_or_split(iterator *iter) { // Create a new root node and set the current root node as the child of the // new root. parent = new_internal_node(parent); + parent->set_generation(root()->generation()); parent->init_child(parent->start(), root()); mutable_root() = parent; // If the former root was a leaf node, then it's now the rightmost node. - assert(!parent->start_child()->leaf() || - parent->start_child() == rightmost_); + assert(parent->start_child()->is_internal() || + parent->start_child() == rightmost()); } // Split the node. node_type *split_node; - if (node->leaf()) { + if (node->is_leaf()) { split_node = new_leaf_node(parent); node->split(insert_position, split_node, mutable_allocator()); - if (rightmost_ == node) rightmost_ = split_node; + if (rightmost() == node) mutable_rightmost() = split_node; } else { split_node = new_internal_node(parent); node->split(insert_position, split_node, mutable_allocator()); @@ -2377,55 +2563,56 @@ void btree<P>::rebalance_or_split(iterator *iter) { template <typename P> void btree<P>::merge_nodes(node_type *left, node_type *right) { left->merge(right, mutable_allocator()); - if (rightmost_ == right) rightmost_ = left; + if (rightmost() == right) mutable_rightmost() = left; } template <typename P> bool btree<P>::try_merge_or_rebalance(iterator *iter) { - node_type *parent = iter->node->parent(); - if (iter->node->position() > parent->start()) { + node_type *parent = iter->node_->parent(); + if (iter->node_->position() > parent->start()) { // Try merging with our left sibling. - node_type *left = parent->child(iter->node->position() - 1); + node_type *left = parent->child(iter->node_->position() - 1); assert(left->max_count() == kNodeSlots); - if (1U + left->count() + iter->node->count() <= kNodeSlots) { - iter->position += 1 + left->count(); - merge_nodes(left, iter->node); - iter->node = left; + if (1U + left->count() + iter->node_->count() <= kNodeSlots) { + iter->position_ += 1 + left->count(); + merge_nodes(left, iter->node_); + iter->node_ = left; return true; } } - if (iter->node->position() < parent->finish()) { + if (iter->node_->position() < parent->finish()) { // Try merging with our right sibling. - node_type *right = parent->child(iter->node->position() + 1); + node_type *right = parent->child(iter->node_->position() + 1); assert(right->max_count() == kNodeSlots); - if (1U + iter->node->count() + right->count() <= kNodeSlots) { - merge_nodes(iter->node, right); + if (1U + iter->node_->count() + right->count() <= kNodeSlots) { + merge_nodes(iter->node_, right); return true; } // Try rebalancing with our right sibling. We don't perform rebalancing if - // we deleted the first element from iter->node and the node is not + // we deleted the first element from iter->node_ and the node is not // empty. This is a small optimization for the common pattern of deleting // from the front of the tree. if (right->count() > kMinNodeValues && - (iter->node->count() == 0 || iter->position > iter->node->start())) { - int to_move = (right->count() - iter->node->count()) / 2; + (iter->node_->count() == 0 || iter->position_ > iter->node_->start())) { + int to_move = (right->count() - iter->node_->count()) / 2; to_move = (std::min)(to_move, right->count() - 1); - iter->node->rebalance_right_to_left(to_move, right, mutable_allocator()); + iter->node_->rebalance_right_to_left(to_move, right, mutable_allocator()); return false; } } - if (iter->node->position() > parent->start()) { + if (iter->node_->position() > parent->start()) { // Try rebalancing with our left sibling. We don't perform rebalancing if - // we deleted the last element from iter->node and the node is not + // we deleted the last element from iter->node_ and the node is not // empty. This is a small optimization for the common pattern of deleting // from the back of the tree. - node_type *left = parent->child(iter->node->position() - 1); + node_type *left = parent->child(iter->node_->position() - 1); if (left->count() > kMinNodeValues && - (iter->node->count() == 0 || iter->position < iter->node->finish())) { - int to_move = (left->count() - iter->node->count()) / 2; + (iter->node_->count() == 0 || + iter->position_ < iter->node_->finish())) { + int to_move = (left->count() - iter->node_->count()) / 2; to_move = (std::min)(to_move, left->count() - 1); - left->rebalance_left_to_right(to_move, iter->node, mutable_allocator()); - iter->position += to_move; + left->rebalance_left_to_right(to_move, iter->node_, mutable_allocator()); + iter->position_ += to_move; return false; } } @@ -2439,9 +2626,9 @@ void btree<P>::try_shrink() { return; } // Deleted the last item on the root node, shrink the height of the tree. - if (orig_root->leaf()) { + if (orig_root->is_leaf()) { assert(size() == 0); - mutable_root() = rightmost_ = EmptyNode(); + mutable_root() = mutable_rightmost() = EmptyNode(); } else { node_type *child = orig_root->start_child(); child->make_root(); @@ -2453,15 +2640,16 @@ void btree<P>::try_shrink() { template <typename P> template <typename IterType> inline IterType btree<P>::internal_last(IterType iter) { - assert(iter.node != nullptr); - while (iter.position == iter.node->finish()) { - iter.position = iter.node->position(); - iter.node = iter.node->parent(); - if (iter.node->leaf()) { - iter.node = nullptr; + assert(iter.node_ != nullptr); + while (iter.position_ == iter.node_->finish()) { + iter.position_ = iter.node_->position(); + iter.node_ = iter.node_->parent(); + if (iter.node_->is_leaf()) { + iter.node_ = nullptr; break; } } + iter.update_generation(); return iter; } @@ -2469,37 +2657,39 @@ template <typename P> template <typename... Args> inline auto btree<P>::internal_emplace(iterator iter, Args &&... args) -> iterator { - if (!iter.node->leaf()) { + if (iter.node_->is_internal()) { // We can't insert on an internal node. Instead, we'll insert after the // previous value which is guaranteed to be on a leaf node. --iter; - ++iter.position; + ++iter.position_; } - const field_type max_count = iter.node->max_count(); + const field_type max_count = iter.node_->max_count(); allocator_type *alloc = mutable_allocator(); - if (iter.node->count() == max_count) { + if (iter.node_->count() == max_count) { // Make room in the leaf for the new item. if (max_count < kNodeSlots) { // Insertion into the root where the root is smaller than the full node // size. Simply grow the size of the root node. - assert(iter.node == root()); - iter.node = + assert(iter.node_ == root()); + iter.node_ = new_leaf_root_node((std::min<int>)(kNodeSlots, 2 * max_count)); // Transfer the values from the old root to the new root. node_type *old_root = root(); - node_type *new_root = iter.node; + node_type *new_root = iter.node_; new_root->transfer_n(old_root->count(), new_root->start(), old_root->start(), old_root, alloc); new_root->set_finish(old_root->finish()); old_root->set_finish(old_root->start()); + new_root->set_generation(old_root->generation()); node_type::clear_and_delete(old_root, alloc); - mutable_root() = rightmost_ = new_root; + mutable_root() = mutable_rightmost() = new_root; } else { rebalance_or_split(&iter); } } - iter.node->emplace_value(iter.position, alloc, std::forward<Args>(args)...); + iter.node_->emplace_value(iter.position_, alloc, std::forward<Args>(args)...); ++size_; + iter.update_generation(); return iter; } @@ -2510,8 +2700,8 @@ inline auto btree<P>::internal_locate(const K &key) const iterator iter(const_cast<node_type *>(root())); for (;;) { SearchResult<int, is_key_compare_to::value> res = - iter.node->lower_bound(key, key_comp()); - iter.position = res.value; + iter.node_->lower_bound(key, key_comp()); + iter.position_ = res.value; if (res.IsEq()) { return {iter, MatchKind::kEq}; } @@ -2519,10 +2709,10 @@ inline auto btree<P>::internal_locate(const K &key) const // down the tree if the keys are equal, but determining equality would // require doing an extra comparison on each node on the way down, and we // will need to go all the way to the leaf node in the expected case. - if (iter.node->leaf()) { + if (iter.node_->is_leaf()) { break; } - iter.node = iter.node->child(iter.position); + iter.node_ = iter.node_->child(iter.position_); } // Note: in the non-key-compare-to case, the key may actually be equivalent // here (and the MatchKind::kNe is ignored). @@ -2542,13 +2732,13 @@ auto btree<P>::internal_lower_bound(const K &key) const SearchResult<int, is_key_compare_to::value> res; bool seen_eq = false; for (;;) { - res = iter.node->lower_bound(key, key_comp()); - iter.position = res.value; - if (iter.node->leaf()) { + res = iter.node_->lower_bound(key, key_comp()); + iter.position_ = res.value; + if (iter.node_->is_leaf()) { break; } seen_eq = seen_eq || res.IsEq(); - iter.node = iter.node->child(iter.position); + iter.node_ = iter.node_->child(iter.position_); } if (res.IsEq()) return {iter, MatchKind::kEq}; return {internal_last(iter), seen_eq ? MatchKind::kEq : MatchKind::kNe}; @@ -2559,11 +2749,11 @@ template <typename K> auto btree<P>::internal_upper_bound(const K &key) const -> iterator { iterator iter(const_cast<node_type *>(root())); for (;;) { - iter.position = iter.node->upper_bound(key, key_comp()); - if (iter.node->leaf()) { + iter.position_ = iter.node_->upper_bound(key, key_comp()); + if (iter.node_->is_leaf()) { break; } - iter.node = iter.node->child(iter.position); + iter.node_ = iter.node_->child(iter.position_); } return internal_last(iter); } @@ -2578,7 +2768,7 @@ auto btree<P>::internal_find(const K &key) const -> iterator { } } else { const iterator iter = internal_last(res.value); - if (iter.node != nullptr && !compare_keys(key, iter.key())) { + if (iter.node_ != nullptr && !compare_keys(key, iter.key())) { return iter; } } @@ -2600,7 +2790,7 @@ int btree<P>::internal_verify(const node_type *node, const key_type *lo, assert(!compare_keys(node->key(i), node->key(i - 1))); } int count = node->count(); - if (!node->leaf()) { + if (node->is_internal()) { for (int i = node->start(); i <= node->finish(); ++i) { assert(node->child(i) != nullptr); assert(node->child(i)->parent() == node); @@ -2613,6 +2803,50 @@ int btree<P>::internal_verify(const node_type *node, const key_type *lo, return count; } +struct btree_access { + template <typename BtreeContainer, typename Pred> + static auto erase_if(BtreeContainer &container, Pred pred) + -> typename BtreeContainer::size_type { + const auto initial_size = container.size(); + auto &tree = container.tree_; + auto *alloc = tree.mutable_allocator(); + for (auto it = container.begin(); it != container.end();) { + if (!pred(*it)) { + ++it; + continue; + } + auto *node = it.node_; + if (node->is_internal()) { + // Handle internal nodes normally. + it = container.erase(it); + continue; + } + // If this is a leaf node, then we do all the erases from this node + // at once before doing rebalancing. + + // The current position to transfer slots to. + int to_pos = it.position_; + node->value_destroy(it.position_, alloc); + while (++it.position_ < node->finish()) { + it.update_generation(); + if (pred(*it)) { + node->value_destroy(it.position_, alloc); + } else { + node->transfer(node->slot(to_pos++), node->slot(it.position_), alloc); + } + } + const int num_deleted = node->finish() - to_pos; + tree.size_ -= num_deleted; + node->set_finish(to_pos); + it.position_ = to_pos; + it = tree.rebalance_after_delete(it); + } + return initial_size - container.size(); + } +}; + +#undef ABSL_BTREE_ENABLE_GENERATIONS + } // namespace container_internal ABSL_NAMESPACE_END } // namespace absl diff --git a/absl/container/internal/btree_container.h b/absl/container/internal/btree_container.h index 03be708e..fc2f740a 100644 --- a/absl/container/internal/btree_container.h +++ b/absl/container/internal/btree_container.h @@ -20,6 +20,7 @@ #include <iterator> #include <utility> +#include "absl/base/attributes.h" #include "absl/base/internal/throw_delegate.h" #include "absl/container/internal/btree.h" // IWYU pragma: export #include "absl/container/internal/common.h" @@ -43,15 +44,15 @@ class btree_container { // transparent case. template <class K> using key_arg = - typename KeyArg<IsTransparent<typename Tree::key_compare>::value>:: - template type<K, typename Tree::key_type>; + typename KeyArg<params_type::kIsKeyCompareTransparent>::template type< + K, typename Tree::key_type>; public: using key_type = typename Tree::key_type; using value_type = typename Tree::value_type; using size_type = typename Tree::size_type; using difference_type = typename Tree::difference_type; - using key_compare = typename Tree::key_compare; + using key_compare = typename Tree::original_key_compare; using value_compare = typename Tree::value_compare; using allocator_type = typename Tree::allocator_type; using reference = typename Tree::reference; @@ -165,9 +166,10 @@ class btree_container { // Extract routines. node_type extract(iterator position) { - // Use Move instead of Transfer, because the rebalancing code expects to - // have a valid object to scribble metadata bits on top of. - auto node = CommonAccess::Move<node_type>(get_allocator(), position.slot()); + // Use Construct instead of Transfer because the rebalancing code will + // destroy the slot later. + auto node = + CommonAccess::Construct<node_type>(get_allocator(), position.slot()); erase(position); return node; } @@ -176,7 +178,7 @@ class btree_container { } // Utility routines. - void clear() { tree_.clear(); } + ABSL_ATTRIBUTE_REINITIALIZES void clear() { tree_.clear(); } void swap(btree_container &other) { tree_.swap(other.tree_); } void verify() const { tree_.verify(); } @@ -214,7 +216,7 @@ class btree_container { allocator_type get_allocator() const { return tree_.get_allocator(); } // The key comparator used by the btree. - key_compare key_comp() const { return tree_.key_comp(); } + key_compare key_comp() const { return key_compare(tree_.key_comp()); } value_compare value_comp() const { return tree_.value_comp(); } // Support absl::Hash. @@ -227,6 +229,7 @@ class btree_container { } protected: + friend struct btree_access; Tree tree_; }; @@ -247,7 +250,7 @@ class btree_set_container : public btree_container<Tree> { using key_type = typename Tree::key_type; using value_type = typename Tree::value_type; using size_type = typename Tree::size_type; - using key_compare = typename Tree::key_compare; + using key_compare = typename Tree::original_key_compare; using allocator_type = typename Tree::allocator_type; using iterator = typename Tree::iterator; using const_iterator = typename Tree::const_iterator; @@ -289,8 +292,11 @@ class btree_set_container : public btree_container<Tree> { } template <typename... Args> std::pair<iterator, bool> emplace(Args &&... args) { - init_type v(std::forward<Args>(args)...); - return this->tree_.insert_unique(params_type::key(v), std::move(v)); + // Use a node handle to manage a temp slot. + auto node = CommonAccess::Construct<node_type>(this->get_allocator(), + std::forward<Args>(args)...); + auto *slot = CommonAccess::GetSlot(node); + return this->tree_.insert_unique(params_type::key(slot), slot); } iterator insert(const_iterator hint, const value_type &v) { return this->tree_ @@ -304,9 +310,12 @@ class btree_set_container : public btree_container<Tree> { } template <typename... Args> iterator emplace_hint(const_iterator hint, Args &&... args) { - init_type v(std::forward<Args>(args)...); + // Use a node handle to manage a temp slot. + auto node = CommonAccess::Construct<node_type>(this->get_allocator(), + std::forward<Args>(args)...); + auto *slot = CommonAccess::GetSlot(node); return this->tree_ - .insert_hint_unique(iterator(hint), params_type::key(v), std::move(v)) + .insert_hint_unique(iterator(hint), params_type::key(slot), slot) .first; } template <typename InputIterator> @@ -398,7 +407,7 @@ class btree_map_container : public btree_set_container<Tree> { using key_type = typename Tree::key_type; using mapped_type = typename params_type::mapped_type; using value_type = typename Tree::value_type; - using key_compare = typename Tree::key_compare; + using key_compare = typename Tree::original_key_compare; using allocator_type = typename Tree::allocator_type; using iterator = typename Tree::iterator; using const_iterator = typename Tree::const_iterator; @@ -535,6 +544,7 @@ class btree_multiset_container : public btree_container<Tree> { using params_type = typename Tree::params_type; using init_type = typename params_type::init_type; using is_key_compare_to = typename params_type::is_key_compare_to; + friend class BtreeNodePeer; template <class K> using key_arg = typename super_type::template key_arg<K>; @@ -543,7 +553,7 @@ class btree_multiset_container : public btree_container<Tree> { using key_type = typename Tree::key_type; using value_type = typename Tree::value_type; using size_type = typename Tree::size_type; - using key_compare = typename Tree::key_compare; + using key_compare = typename Tree::original_key_compare; using allocator_type = typename Tree::allocator_type; using iterator = typename Tree::iterator; using const_iterator = typename Tree::const_iterator; @@ -595,12 +605,18 @@ class btree_multiset_container : public btree_container<Tree> { } template <typename... Args> iterator emplace(Args &&... args) { - return this->tree_.insert_multi(init_type(std::forward<Args>(args)...)); + // Use a node handle to manage a temp slot. + auto node = CommonAccess::Construct<node_type>(this->get_allocator(), + std::forward<Args>(args)...); + return this->tree_.insert_multi(CommonAccess::GetSlot(node)); } template <typename... Args> iterator emplace_hint(const_iterator hint, Args &&... args) { - return this->tree_.insert_hint_multi( - iterator(hint), init_type(std::forward<Args>(args)...)); + // Use a node handle to manage a temp slot. + auto node = CommonAccess::Construct<node_type>(this->get_allocator(), + std::forward<Args>(args)...); + return this->tree_.insert_hint_multi(iterator(hint), + CommonAccess::GetSlot(node)); } iterator insert(node_type &&node) { if (!node) return this->end(); @@ -666,6 +682,7 @@ template <typename Tree> class btree_multimap_container : public btree_multiset_container<Tree> { using super_type = btree_multiset_container<Tree>; using params_type = typename Tree::params_type; + friend class BtreeNodePeer; public: using mapped_type = typename params_type::mapped_type; diff --git a/absl/container/internal/common.h b/absl/container/internal/common.h index 030e9d4a..416d9aa3 100644 --- a/absl/container/internal/common.h +++ b/absl/container/internal/common.h @@ -84,10 +84,11 @@ class node_handle_base { PolicyTraits::transfer(alloc(), slot(), s); } - struct move_tag_t {}; - node_handle_base(move_tag_t, const allocator_type& a, slot_type* s) + struct construct_tag_t {}; + template <typename... Args> + node_handle_base(construct_tag_t, const allocator_type& a, Args&&... args) : alloc_(a) { - PolicyTraits::construct(alloc(), slot(), s); + PolicyTraits::construct(alloc(), slot(), std::forward<Args>(args)...); } void destroy() { @@ -186,8 +187,8 @@ struct CommonAccess { } template <typename T, typename... Args> - static T Move(Args&&... args) { - return T(typename T::move_tag_t{}, std::forward<Args>(args)...); + static T Construct(Args&&... args) { + return T(typename T::construct_tag_t{}, std::forward<Args>(args)...); } }; diff --git a/absl/container/internal/compressed_tuple_test.cc b/absl/container/internal/compressed_tuple_test.cc index 62a7483e..74111f97 100644 --- a/absl/container/internal/compressed_tuple_test.cc +++ b/absl/container/internal/compressed_tuple_test.cc @@ -403,6 +403,16 @@ TEST(CompressedTupleTest, EmptyFinalClass) { } #endif +// TODO(b/214288561): enable this test. +TEST(CompressedTupleTest, DISABLED_NestedEbo) { + struct Empty1 {}; + struct Empty2 {}; + CompressedTuple<Empty1, CompressedTuple<Empty2>, int> x; + CompressedTuple<Empty1, Empty2, int> y; + // Currently fails with sizeof(x) == 8, sizeof(y) == 4. + EXPECT_EQ(sizeof(x), sizeof(y)); +} + } // namespace } // namespace container_internal ABSL_NAMESPACE_END diff --git a/absl/container/internal/container_memory.h b/absl/container/internal/container_memory.h index e67529ec..00e9f6d7 100644 --- a/absl/container/internal/container_memory.h +++ b/absl/container/internal/container_memory.h @@ -174,7 +174,7 @@ decltype(std::declval<F>()(std::declval<T>())) WithConstructed( // // 2. auto a = PairArgs(args...); // std::pair<F, S> p(std::piecewise_construct, -// std::move(p.first), std::move(p.second)); +// std::move(a.first), std::move(a.second)); inline std::pair<std::tuple<>, std::tuple<>> PairArgs() { return {}; } template <class F, class S> std::pair<std::tuple<F&&>, std::tuple<S&&>> PairArgs(F&& f, S&& s) { @@ -402,6 +402,15 @@ struct map_slot_policy { } } + // Construct this slot by copying from another slot. + template <class Allocator> + static void construct(Allocator* alloc, slot_type* slot, + const slot_type* other) { + emplace(slot); + absl::allocator_traits<Allocator>::construct(*alloc, &slot->value, + other->value); + } + template <class Allocator> static void destroy(Allocator* alloc, slot_type* slot) { if (kMutableKeys::value) { @@ -424,33 +433,6 @@ struct map_slot_policy { } destroy(alloc, old_slot); } - - template <class Allocator> - static void swap(Allocator* alloc, slot_type* a, slot_type* b) { - if (kMutableKeys::value) { - using std::swap; - swap(a->mutable_value, b->mutable_value); - } else { - value_type tmp = std::move(a->value); - absl::allocator_traits<Allocator>::destroy(*alloc, &a->value); - absl::allocator_traits<Allocator>::construct(*alloc, &a->value, - std::move(b->value)); - absl::allocator_traits<Allocator>::destroy(*alloc, &b->value); - absl::allocator_traits<Allocator>::construct(*alloc, &b->value, - std::move(tmp)); - } - } - - template <class Allocator> - static void move(Allocator* alloc, slot_type* src, slot_type* dest) { - if (kMutableKeys::value) { - dest->mutable_value = std::move(src->mutable_value); - } else { - absl::allocator_traits<Allocator>::destroy(*alloc, &dest->value); - absl::allocator_traits<Allocator>::construct(*alloc, &dest->value, - std::move(src->value)); - } - } }; } // namespace container_internal diff --git a/absl/container/internal/counting_allocator.h b/absl/container/internal/counting_allocator.h index 927cf082..66068a5a 100644 --- a/absl/container/internal/counting_allocator.h +++ b/absl/container/internal/counting_allocator.h @@ -80,7 +80,15 @@ class CountingAllocator { template <typename U> void destroy(U* p) { Allocator allocator; + // Ignore GCC warning bug. +#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0) +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wuse-after-free" +#endif AllocatorTraits::destroy(allocator, p); +#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0) +#pragma GCC diagnostic pop +#endif if (instance_count_ != nullptr) { *instance_count_ -= 1; } diff --git a/absl/container/internal/hash_function_defaults.h b/absl/container/internal/hash_function_defaults.h index 0683422a..250e662c 100644 --- a/absl/container/internal/hash_function_defaults.h +++ b/absl/container/internal/hash_function_defaults.h @@ -78,24 +78,26 @@ struct StringHash { } }; +struct StringEq { + using is_transparent = void; + bool operator()(absl::string_view lhs, absl::string_view rhs) const { + return lhs == rhs; + } + bool operator()(const absl::Cord& lhs, const absl::Cord& rhs) const { + return lhs == rhs; + } + bool operator()(const absl::Cord& lhs, absl::string_view rhs) const { + return lhs == rhs; + } + bool operator()(absl::string_view lhs, const absl::Cord& rhs) const { + return lhs == rhs; + } +}; + // Supports heterogeneous lookup for string-like elements. struct StringHashEq { using Hash = StringHash; - struct Eq { - using is_transparent = void; - bool operator()(absl::string_view lhs, absl::string_view rhs) const { - return lhs == rhs; - } - bool operator()(const absl::Cord& lhs, const absl::Cord& rhs) const { - return lhs == rhs; - } - bool operator()(const absl::Cord& lhs, absl::string_view rhs) const { - return lhs == rhs; - } - bool operator()(absl::string_view lhs, const absl::Cord& rhs) const { - return lhs == rhs; - } - }; + using Eq = StringEq; }; template <> diff --git a/absl/container/internal/hash_function_defaults_test.cc b/absl/container/internal/hash_function_defaults_test.cc index 59576b8e..9f0a4c72 100644 --- a/absl/container/internal/hash_function_defaults_test.cc +++ b/absl/container/internal/hash_function_defaults_test.cc @@ -310,7 +310,7 @@ struct StringLikeTest : public ::testing::Test { hash_default_hash<typename T::first_type> hash; }; -TYPED_TEST_CASE_P(StringLikeTest); +TYPED_TEST_SUITE_P(StringLikeTest); TYPED_TEST_P(StringLikeTest, Eq) { EXPECT_TRUE(this->eq(this->a1, this->b1)); diff --git a/absl/container/internal/hash_generator_testing.h b/absl/container/internal/hash_generator_testing.h index 6869fe45..f1f555a5 100644 --- a/absl/container/internal/hash_generator_testing.h +++ b/absl/container/internal/hash_generator_testing.h @@ -21,11 +21,13 @@ #include <stdint.h> #include <algorithm> +#include <cassert> #include <iosfwd> #include <random> #include <tuple> #include <type_traits> #include <utility> +#include <vector> #include "absl/container/internal/hash_policy_testing.h" #include "absl/memory/memory.h" @@ -153,6 +155,25 @@ using GeneratedType = decltype( typename Container::value_type, typename Container::key_type>::type>&>()()); +// Naive wrapper that performs a linear search of previous values. +// Beware this is O(SQR), which is reasonable for smaller kMaxValues. +template <class T, size_t kMaxValues = 64, class E = void> +struct UniqueGenerator { + Generator<T, E> gen; + std::vector<T> values; + + T operator()() { + assert(values.size() < kMaxValues); + for (;;) { + T value = gen(); + if (std::find(values.begin(), values.end(), value) == values.end()) { + values.push_back(value); + return value; + } + } + } +}; + } // namespace hash_internal } // namespace container_internal ABSL_NAMESPACE_END diff --git a/absl/container/internal/hashtablez_sampler.cc b/absl/container/internal/hashtablez_sampler.cc index 5a29bed7..efc1be58 100644 --- a/absl/container/internal/hashtablez_sampler.cc +++ b/absl/container/internal/hashtablez_sampler.cc @@ -21,49 +21,55 @@ #include <limits> #include "absl/base/attributes.h" -#include "absl/base/internal/exponential_biased.h" -#include "absl/container/internal/have_sse.h" +#include "absl/base/config.h" #include "absl/debugging/stacktrace.h" #include "absl/memory/memory.h" +#include "absl/profiling/internal/exponential_biased.h" +#include "absl/profiling/internal/sample_recorder.h" #include "absl/synchronization/mutex.h" +#include "absl/utility/utility.h" namespace absl { ABSL_NAMESPACE_BEGIN namespace container_internal { + +#ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL constexpr int HashtablezInfo::kMaxStackDepth; +#endif namespace { ABSL_CONST_INIT std::atomic<bool> g_hashtablez_enabled{ false }; ABSL_CONST_INIT std::atomic<int32_t> g_hashtablez_sample_parameter{1 << 10}; -ABSL_CONST_INIT std::atomic<int32_t> g_hashtablez_max_samples{1 << 20}; +std::atomic<HashtablezConfigListener> g_hashtablez_config_listener{nullptr}; #if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) -ABSL_PER_THREAD_TLS_KEYWORD absl::base_internal::ExponentialBiased +ABSL_PER_THREAD_TLS_KEYWORD absl::profiling_internal::ExponentialBiased g_exponential_biased_generator; #endif +void TriggerHashtablezConfigListener() { + auto* listener = g_hashtablez_config_listener.load(std::memory_order_acquire); + if (listener != nullptr) listener(); +} + } // namespace #if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) -ABSL_PER_THREAD_TLS_KEYWORD int64_t global_next_sample = 0; +ABSL_PER_THREAD_TLS_KEYWORD SamplingState global_next_sample = {0, 0}; #endif // defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) -HashtablezSampler& HashtablezSampler::Global() { +HashtablezSampler& GlobalHashtablezSampler() { static auto* sampler = new HashtablezSampler(); return *sampler; } -HashtablezSampler::DisposeCallback HashtablezSampler::SetDisposeCallback( - DisposeCallback f) { - return dispose_.exchange(f, std::memory_order_relaxed); -} - -HashtablezInfo::HashtablezInfo() { PrepareForSampling(); } +HashtablezInfo::HashtablezInfo() = default; HashtablezInfo::~HashtablezInfo() = default; -void HashtablezInfo::PrepareForSampling() { +void HashtablezInfo::PrepareForSampling(int64_t stride, + size_t inline_element_size_value) { capacity.store(0, std::memory_order_relaxed); size.store(0, std::memory_order_relaxed); num_erases.store(0, std::memory_order_relaxed); @@ -73,100 +79,16 @@ void HashtablezInfo::PrepareForSampling() { hashes_bitwise_or.store(0, std::memory_order_relaxed); hashes_bitwise_and.store(~size_t{}, std::memory_order_relaxed); hashes_bitwise_xor.store(0, std::memory_order_relaxed); + max_reserve.store(0, std::memory_order_relaxed); create_time = absl::Now(); + weight = stride; // The inliner makes hardcoded skip_count difficult (especially when combined // with LTO). We use the ability to exclude stacks by regex when encoding // instead. depth = absl::GetStackTrace(stack, HashtablezInfo::kMaxStackDepth, /* skip_count= */ 0); - dead = nullptr; -} - -HashtablezSampler::HashtablezSampler() - : dropped_samples_(0), size_estimate_(0), all_(nullptr), dispose_(nullptr) { - absl::MutexLock l(&graveyard_.init_mu); - graveyard_.dead = &graveyard_; -} - -HashtablezSampler::~HashtablezSampler() { - HashtablezInfo* s = all_.load(std::memory_order_acquire); - while (s != nullptr) { - HashtablezInfo* next = s->next; - delete s; - s = next; - } -} - -void HashtablezSampler::PushNew(HashtablezInfo* sample) { - sample->next = all_.load(std::memory_order_relaxed); - while (!all_.compare_exchange_weak(sample->next, sample, - std::memory_order_release, - std::memory_order_relaxed)) { - } -} - -void HashtablezSampler::PushDead(HashtablezInfo* sample) { - if (auto* dispose = dispose_.load(std::memory_order_relaxed)) { - dispose(*sample); - } - - absl::MutexLock graveyard_lock(&graveyard_.init_mu); - absl::MutexLock sample_lock(&sample->init_mu); - sample->dead = graveyard_.dead; - graveyard_.dead = sample; -} - -HashtablezInfo* HashtablezSampler::PopDead() { - absl::MutexLock graveyard_lock(&graveyard_.init_mu); - - // The list is circular, so eventually it collapses down to - // graveyard_.dead == &graveyard_ - // when it is empty. - HashtablezInfo* sample = graveyard_.dead; - if (sample == &graveyard_) return nullptr; - - absl::MutexLock sample_lock(&sample->init_mu); - graveyard_.dead = sample->dead; - sample->PrepareForSampling(); - return sample; -} - -HashtablezInfo* HashtablezSampler::Register() { - int64_t size = size_estimate_.fetch_add(1, std::memory_order_relaxed); - if (size > g_hashtablez_max_samples.load(std::memory_order_relaxed)) { - size_estimate_.fetch_sub(1, std::memory_order_relaxed); - dropped_samples_.fetch_add(1, std::memory_order_relaxed); - return nullptr; - } - - HashtablezInfo* sample = PopDead(); - if (sample == nullptr) { - // Resurrection failed. Hire a new warlock. - sample = new HashtablezInfo(); - PushNew(sample); - } - - return sample; -} - -void HashtablezSampler::Unregister(HashtablezInfo* sample) { - PushDead(sample); - size_estimate_.fetch_sub(1, std::memory_order_relaxed); -} - -int64_t HashtablezSampler::Iterate( - const std::function<void(const HashtablezInfo& stack)>& f) { - HashtablezInfo* s = all_.load(std::memory_order_acquire); - while (s != nullptr) { - absl::MutexLock l(&s->init_mu); - if (s->dead == nullptr) { - f(*s); - } - s = s->next; - } - - return dropped_samples_.load(std::memory_order_relaxed); + inline_element_size = inline_element_size_value; } static bool ShouldForceSampling() { @@ -189,21 +111,32 @@ static bool ShouldForceSampling() { return state == kForce; } -HashtablezInfo* SampleSlow(int64_t* next_sample) { +HashtablezInfo* SampleSlow(SamplingState& next_sample, + size_t inline_element_size) { if (ABSL_PREDICT_FALSE(ShouldForceSampling())) { - *next_sample = 1; - return HashtablezSampler::Global().Register(); + next_sample.next_sample = 1; + const int64_t old_stride = exchange(next_sample.sample_stride, 1); + HashtablezInfo* result = + GlobalHashtablezSampler().Register(old_stride, inline_element_size); + return result; } #if !defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) - *next_sample = std::numeric_limits<int64_t>::max(); + next_sample = { + std::numeric_limits<int64_t>::max(), + std::numeric_limits<int64_t>::max(), + }; return nullptr; #else - bool first = *next_sample < 0; - *next_sample = g_exponential_biased_generator.GetStride( + bool first = next_sample.next_sample < 0; + + const int64_t next_stride = g_exponential_biased_generator.GetStride( g_hashtablez_sample_parameter.load(std::memory_order_relaxed)); + + next_sample.next_sample = next_stride; + const int64_t old_stride = exchange(next_sample.sample_stride, next_stride); // Small values of interval are equivalent to just sampling next time. - ABSL_ASSERT(*next_sample >= 1); + ABSL_ASSERT(next_stride >= 1); // g_hashtablez_enabled can be dynamically flipped, we need to set a threshold // low enough that we will start sampling in a reasonable time, so we just use @@ -213,16 +146,16 @@ HashtablezInfo* SampleSlow(int64_t* next_sample) { // We will only be negative on our first count, so we should just retry in // that case. if (first) { - if (ABSL_PREDICT_TRUE(--*next_sample > 0)) return nullptr; - return SampleSlow(next_sample); + if (ABSL_PREDICT_TRUE(--next_sample.next_sample > 0)) return nullptr; + return SampleSlow(next_sample, inline_element_size); } - return HashtablezSampler::Global().Register(); + return GlobalHashtablezSampler().Register(old_stride, inline_element_size); #endif } void UnsampleSlow(HashtablezInfo* info) { - HashtablezSampler::Global().Unregister(info); + GlobalHashtablezSampler().Unregister(info); } void RecordInsertSlow(HashtablezInfo* info, size_t hash, @@ -230,7 +163,7 @@ void RecordInsertSlow(HashtablezInfo* info, size_t hash, // SwissTables probe in groups of 16, so scale this to count items probes and // not offset from desired. size_t probe_length = distance_from_desired; -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 +#ifdef ABSL_INTERNAL_HAVE_SSE2 probe_length /= 16; #else probe_length /= 8; @@ -247,11 +180,33 @@ void RecordInsertSlow(HashtablezInfo* info, size_t hash, info->size.fetch_add(1, std::memory_order_relaxed); } +void SetHashtablezConfigListener(HashtablezConfigListener l) { + g_hashtablez_config_listener.store(l, std::memory_order_release); +} + +bool IsHashtablezEnabled() { + return g_hashtablez_enabled.load(std::memory_order_acquire); +} + void SetHashtablezEnabled(bool enabled) { + SetHashtablezEnabledInternal(enabled); + TriggerHashtablezConfigListener(); +} + +void SetHashtablezEnabledInternal(bool enabled) { g_hashtablez_enabled.store(enabled, std::memory_order_release); } +int32_t GetHashtablezSampleParameter() { + return g_hashtablez_sample_parameter.load(std::memory_order_acquire); +} + void SetHashtablezSampleParameter(int32_t rate) { + SetHashtablezSampleParameterInternal(rate); + TriggerHashtablezConfigListener(); +} + +void SetHashtablezSampleParameterInternal(int32_t rate) { if (rate > 0) { g_hashtablez_sample_parameter.store(rate, std::memory_order_release); } else { @@ -260,9 +215,18 @@ void SetHashtablezSampleParameter(int32_t rate) { } } +int32_t GetHashtablezMaxSamples() { + return GlobalHashtablezSampler().GetMaxSamples(); +} + void SetHashtablezMaxSamples(int32_t max) { + SetHashtablezMaxSamplesInternal(max); + TriggerHashtablezConfigListener(); +} + +void SetHashtablezMaxSamplesInternal(int32_t max) { if (max > 0) { - g_hashtablez_max_samples.store(max, std::memory_order_release); + GlobalHashtablezSampler().SetMaxSamples(max); } else { ABSL_RAW_LOG(ERROR, "Invalid hashtablez max samples: %lld", static_cast<long long>(max)); // NOLINT(runtime/int) diff --git a/absl/container/internal/hashtablez_sampler.h b/absl/container/internal/hashtablez_sampler.h index 85685f72..d4016d8a 100644 --- a/absl/container/internal/hashtablez_sampler.h +++ b/absl/container/internal/hashtablez_sampler.h @@ -44,9 +44,10 @@ #include <memory> #include <vector> +#include "absl/base/config.h" #include "absl/base/internal/per_thread_tls.h" #include "absl/base/optimization.h" -#include "absl/container/internal/have_sse.h" +#include "absl/profiling/internal/sample_recorder.h" #include "absl/synchronization/mutex.h" #include "absl/utility/utility.h" @@ -57,7 +58,7 @@ namespace container_internal { // Stores information about a sampled hashtable. All mutations to this *must* // be made through `Record*` functions below. All reads from this *must* only // occur in the callback to `HashtablezSampler::Iterate`. -struct HashtablezInfo { +struct HashtablezInfo : public profiling_internal::Sample<HashtablezInfo> { // Constructs the object but does not fill in any fields. HashtablezInfo(); ~HashtablezInfo(); @@ -66,7 +67,8 @@ struct HashtablezInfo { // Puts the object into a clean state, fills in the logically `const` members, // blocking for any readers that are currently sampling the object. - void PrepareForSampling() ABSL_EXCLUSIVE_LOCKS_REQUIRED(init_mu); + void PrepareForSampling(int64_t stride, size_t inline_element_size_value) + ABSL_EXCLUSIVE_LOCKS_REQUIRED(init_mu); // These fields are mutated by the various Record* APIs and need to be // thread-safe. @@ -79,28 +81,22 @@ struct HashtablezInfo { std::atomic<size_t> hashes_bitwise_or; std::atomic<size_t> hashes_bitwise_and; std::atomic<size_t> hashes_bitwise_xor; - - // `HashtablezSampler` maintains intrusive linked lists for all samples. See - // comments on `HashtablezSampler::all_` for details on these. `init_mu` - // guards the ability to restore the sample to a pristine state. This - // prevents races with sampling and resurrecting an object. - absl::Mutex init_mu; - HashtablezInfo* next; - HashtablezInfo* dead ABSL_GUARDED_BY(init_mu); + std::atomic<size_t> max_reserve; // All of the fields below are set by `PrepareForSampling`, they must not be // mutated in `Record*` functions. They are logically `const` in that sense. - // These are guarded by init_mu, but that is not externalized to clients, who - // can only read them during `HashtablezSampler::Iterate` which will hold the - // lock. + // These are guarded by init_mu, but that is not externalized to clients, + // which can read them only during `SampleRecorder::Iterate` which will hold + // the lock. static constexpr int kMaxStackDepth = 64; absl::Time create_time; int32_t depth; void* stack[kMaxStackDepth]; + size_t inline_element_size; // How big is the slot? }; inline void RecordRehashSlow(HashtablezInfo* info, size_t total_probe_length) { -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 +#ifdef ABSL_INTERNAL_HAVE_SSE2 total_probe_length /= 16; #else total_probe_length /= 8; @@ -114,6 +110,18 @@ inline void RecordRehashSlow(HashtablezInfo* info, size_t total_probe_length) { std::memory_order_relaxed); } +inline void RecordReservationSlow(HashtablezInfo* info, + size_t target_capacity) { + info->max_reserve.store( + (std::max)(info->max_reserve.load(std::memory_order_relaxed), + target_capacity), + std::memory_order_relaxed); +} + +inline void RecordClearedReservationSlow(HashtablezInfo* info) { + info->max_reserve.store(0, std::memory_order_relaxed); +} + inline void RecordStorageChangedSlow(HashtablezInfo* info, size_t size, size_t capacity) { info->size.store(size, std::memory_order_relaxed); @@ -137,7 +145,15 @@ inline void RecordEraseSlow(HashtablezInfo* info) { std::memory_order_relaxed); } -HashtablezInfo* SampleSlow(int64_t* next_sample); +struct SamplingState { + int64_t next_sample; + // When we make a sampling decision, we record that distance so we can weight + // each sample. + int64_t sample_stride; +}; + +HashtablezInfo* SampleSlow(SamplingState& next_sample, + size_t inline_element_size); void UnsampleSlow(HashtablezInfo* info); #if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) @@ -177,6 +193,16 @@ class HashtablezInfoHandle { RecordRehashSlow(info_, total_probe_length); } + inline void RecordReservation(size_t target_capacity) { + if (ABSL_PREDICT_TRUE(info_ == nullptr)) return; + RecordReservationSlow(info_, target_capacity); + } + + inline void RecordClearedReservation() { + if (ABSL_PREDICT_TRUE(info_ == nullptr)) return; + RecordClearedReservationSlow(info_); + } + inline void RecordInsert(size_t hash, size_t distance_from_desired) { if (ABSL_PREDICT_TRUE(info_ == nullptr)) return; RecordInsertSlow(info_, hash, distance_from_desired); @@ -206,6 +232,8 @@ class HashtablezInfoHandle { inline void RecordStorageChanged(size_t /*size*/, size_t /*capacity*/) {} inline void RecordRehash(size_t /*total_probe_length*/) {} + inline void RecordReservation(size_t /*target_capacity*/) {} + inline void RecordClearedReservation() {} inline void RecordInsert(size_t /*hash*/, size_t /*distance_from_desired*/) {} inline void RecordErase() {} @@ -215,98 +243,47 @@ class HashtablezInfoHandle { #endif // defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) #if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) -extern ABSL_PER_THREAD_TLS_KEYWORD int64_t global_next_sample; +extern ABSL_PER_THREAD_TLS_KEYWORD SamplingState global_next_sample; #endif // defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) // Returns an RAII sampling handle that manages registration and unregistation // with the global sampler. -inline HashtablezInfoHandle Sample() { +inline HashtablezInfoHandle Sample( + size_t inline_element_size ABSL_ATTRIBUTE_UNUSED) { #if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) - if (ABSL_PREDICT_TRUE(--global_next_sample > 0)) { + if (ABSL_PREDICT_TRUE(--global_next_sample.next_sample > 0)) { return HashtablezInfoHandle(nullptr); } - return HashtablezInfoHandle(SampleSlow(&global_next_sample)); + return HashtablezInfoHandle( + SampleSlow(global_next_sample, inline_element_size)); #else return HashtablezInfoHandle(nullptr); #endif // !ABSL_PER_THREAD_TLS } -// Holds samples and their associated stack traces with a soft limit of -// `SetHashtablezMaxSamples()`. -// -// Thread safe. -class HashtablezSampler { - public: - // Returns a global Sampler. - static HashtablezSampler& Global(); - - HashtablezSampler(); - ~HashtablezSampler(); +using HashtablezSampler = + ::absl::profiling_internal::SampleRecorder<HashtablezInfo>; - // Registers for sampling. Returns an opaque registration info. - HashtablezInfo* Register(); +// Returns a global Sampler. +HashtablezSampler& GlobalHashtablezSampler(); - // Unregisters the sample. - void Unregister(HashtablezInfo* sample); - - // The dispose callback will be called on all samples the moment they are - // being unregistered. Only affects samples that are unregistered after the - // callback has been set. - // Returns the previous callback. - using DisposeCallback = void (*)(const HashtablezInfo&); - DisposeCallback SetDisposeCallback(DisposeCallback f); - - // Iterates over all the registered `StackInfo`s. Returning the number of - // samples that have been dropped. - int64_t Iterate(const std::function<void(const HashtablezInfo& stack)>& f); - - private: - void PushNew(HashtablezInfo* sample); - void PushDead(HashtablezInfo* sample); - HashtablezInfo* PopDead(); - - std::atomic<size_t> dropped_samples_; - std::atomic<size_t> size_estimate_; - - // Intrusive lock free linked lists for tracking samples. - // - // `all_` records all samples (they are never removed from this list) and is - // terminated with a `nullptr`. - // - // `graveyard_.dead` is a circular linked list. When it is empty, - // `graveyard_.dead == &graveyard`. The list is circular so that - // every item on it (even the last) has a non-null dead pointer. This allows - // `Iterate` to determine if a given sample is live or dead using only - // information on the sample itself. - // - // For example, nodes [A, B, C, D, E] with [A, C, E] alive and [B, D] dead - // looks like this (G is the Graveyard): - // - // +---+ +---+ +---+ +---+ +---+ - // all -->| A |--->| B |--->| C |--->| D |--->| E | - // | | | | | | | | | | - // +---+ | | +->| |-+ | | +->| |-+ | | - // | G | +---+ | +---+ | +---+ | +---+ | +---+ - // | | | | | | - // | | --------+ +--------+ | - // +---+ | - // ^ | - // +--------------------------------------+ - // - std::atomic<HashtablezInfo*> all_; - HashtablezInfo graveyard_; - - std::atomic<DisposeCallback> dispose_; -}; +using HashtablezConfigListener = void (*)(); +void SetHashtablezConfigListener(HashtablezConfigListener l); // Enables or disables sampling for Swiss tables. +bool IsHashtablezEnabled(); void SetHashtablezEnabled(bool enabled); +void SetHashtablezEnabledInternal(bool enabled); // Sets the rate at which Swiss tables will be sampled. +int32_t GetHashtablezSampleParameter(); void SetHashtablezSampleParameter(int32_t rate); +void SetHashtablezSampleParameterInternal(int32_t rate); // Sets a soft max for the number of samples that will be kept. +int32_t GetHashtablezMaxSamples(); void SetHashtablezMaxSamples(int32_t max); +void SetHashtablezMaxSamplesInternal(int32_t max); // Configuration override. // This allows process-wide sampling without depending on order of diff --git a/absl/container/internal/hashtablez_sampler_test.cc b/absl/container/internal/hashtablez_sampler_test.cc index 5f4c83b7..665d518f 100644 --- a/absl/container/internal/hashtablez_sampler_test.cc +++ b/absl/container/internal/hashtablez_sampler_test.cc @@ -21,7 +21,8 @@ #include "gmock/gmock.h" #include "gtest/gtest.h" #include "absl/base/attributes.h" -#include "absl/container/internal/have_sse.h" +#include "absl/base/config.h" +#include "absl/profiling/internal/sample_recorder.h" #include "absl/synchronization/blocking_counter.h" #include "absl/synchronization/internal/thread_pool.h" #include "absl/synchronization/mutex.h" @@ -29,7 +30,7 @@ #include "absl/time/clock.h" #include "absl/time/time.h" -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 +#ifdef ABSL_INTERNAL_HAVE_SSE2 constexpr int kProbeLength = 16; #else constexpr int kProbeLength = 8; @@ -69,7 +70,9 @@ std::vector<size_t> GetSizes(HashtablezSampler* s) { } HashtablezInfo* Register(HashtablezSampler* s, size_t size) { - auto* info = s->Register(); + const int64_t test_stride = 123; + const size_t test_element_size = 17; + auto* info = s->Register(test_stride, test_element_size); assert(info != nullptr); info->size.store(size); return info; @@ -77,9 +80,11 @@ HashtablezInfo* Register(HashtablezSampler* s, size_t size) { TEST(HashtablezInfoTest, PrepareForSampling) { absl::Time test_start = absl::Now(); + const int64_t test_stride = 123; + const size_t test_element_size = 17; HashtablezInfo info; absl::MutexLock l(&info.init_mu); - info.PrepareForSampling(); + info.PrepareForSampling(test_stride, test_element_size); EXPECT_EQ(info.capacity.load(), 0); EXPECT_EQ(info.size.load(), 0); @@ -90,7 +95,10 @@ TEST(HashtablezInfoTest, PrepareForSampling) { EXPECT_EQ(info.hashes_bitwise_or.load(), 0); EXPECT_EQ(info.hashes_bitwise_and.load(), ~size_t{}); EXPECT_EQ(info.hashes_bitwise_xor.load(), 0); + EXPECT_EQ(info.max_reserve.load(), 0); EXPECT_GE(info.create_time, test_start); + EXPECT_EQ(info.weight, test_stride); + EXPECT_EQ(info.inline_element_size, test_element_size); info.capacity.store(1, std::memory_order_relaxed); info.size.store(1, std::memory_order_relaxed); @@ -100,9 +108,10 @@ TEST(HashtablezInfoTest, PrepareForSampling) { info.hashes_bitwise_or.store(1, std::memory_order_relaxed); info.hashes_bitwise_and.store(1, std::memory_order_relaxed); info.hashes_bitwise_xor.store(1, std::memory_order_relaxed); + info.max_reserve.store(1, std::memory_order_relaxed); info.create_time = test_start - absl::Hours(20); - info.PrepareForSampling(); + info.PrepareForSampling(test_stride * 2, test_element_size); EXPECT_EQ(info.capacity.load(), 0); EXPECT_EQ(info.size.load(), 0); EXPECT_EQ(info.num_erases.load(), 0); @@ -112,13 +121,18 @@ TEST(HashtablezInfoTest, PrepareForSampling) { EXPECT_EQ(info.hashes_bitwise_or.load(), 0); EXPECT_EQ(info.hashes_bitwise_and.load(), ~size_t{}); EXPECT_EQ(info.hashes_bitwise_xor.load(), 0); + EXPECT_EQ(info.max_reserve.load(), 0); + EXPECT_EQ(info.weight, 2 * test_stride); + EXPECT_EQ(info.inline_element_size, test_element_size); EXPECT_GE(info.create_time, test_start); } TEST(HashtablezInfoTest, RecordStorageChanged) { HashtablezInfo info; absl::MutexLock l(&info.init_mu); - info.PrepareForSampling(); + const int64_t test_stride = 21; + const size_t test_element_size = 19; + info.PrepareForSampling(test_stride, test_element_size); RecordStorageChangedSlow(&info, 17, 47); EXPECT_EQ(info.size.load(), 17); EXPECT_EQ(info.capacity.load(), 47); @@ -130,7 +144,9 @@ TEST(HashtablezInfoTest, RecordStorageChanged) { TEST(HashtablezInfoTest, RecordInsert) { HashtablezInfo info; absl::MutexLock l(&info.init_mu); - info.PrepareForSampling(); + const int64_t test_stride = 25; + const size_t test_element_size = 23; + info.PrepareForSampling(test_stride, test_element_size); EXPECT_EQ(info.max_probe_length.load(), 0); RecordInsertSlow(&info, 0x0000FF00, 6 * kProbeLength); EXPECT_EQ(info.max_probe_length.load(), 6); @@ -150,9 +166,11 @@ TEST(HashtablezInfoTest, RecordInsert) { } TEST(HashtablezInfoTest, RecordErase) { + const int64_t test_stride = 31; + const size_t test_element_size = 29; HashtablezInfo info; absl::MutexLock l(&info.init_mu); - info.PrepareForSampling(); + info.PrepareForSampling(test_stride, test_element_size); EXPECT_EQ(info.num_erases.load(), 0); EXPECT_EQ(info.size.load(), 0); RecordInsertSlow(&info, 0x0000FF00, 6 * kProbeLength); @@ -160,12 +178,15 @@ TEST(HashtablezInfoTest, RecordErase) { RecordEraseSlow(&info); EXPECT_EQ(info.size.load(), 0); EXPECT_EQ(info.num_erases.load(), 1); + EXPECT_EQ(info.inline_element_size, test_element_size); } TEST(HashtablezInfoTest, RecordRehash) { + const int64_t test_stride = 33; + const size_t test_element_size = 31; HashtablezInfo info; absl::MutexLock l(&info.init_mu); - info.PrepareForSampling(); + info.PrepareForSampling(test_stride, test_element_size); RecordInsertSlow(&info, 0x1, 0); RecordInsertSlow(&info, 0x2, kProbeLength); RecordInsertSlow(&info, 0x4, kProbeLength); @@ -184,43 +205,67 @@ TEST(HashtablezInfoTest, RecordRehash) { EXPECT_EQ(info.total_probe_length.load(), 3); EXPECT_EQ(info.num_erases.load(), 0); EXPECT_EQ(info.num_rehashes.load(), 1); + EXPECT_EQ(info.inline_element_size, test_element_size); +} + +TEST(HashtablezInfoTest, RecordReservation) { + HashtablezInfo info; + absl::MutexLock l(&info.init_mu); + const int64_t test_stride = 35; + const size_t test_element_size = 33; + info.PrepareForSampling(test_stride, test_element_size); + RecordReservationSlow(&info, 3); + EXPECT_EQ(info.max_reserve.load(), 3); + + RecordReservationSlow(&info, 2); + // High watermark does not change + EXPECT_EQ(info.max_reserve.load(), 3); + + RecordReservationSlow(&info, 10); + // High watermark does change + EXPECT_EQ(info.max_reserve.load(), 10); } #if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE) TEST(HashtablezSamplerTest, SmallSampleParameter) { + const size_t test_element_size = 31; SetHashtablezEnabled(true); SetHashtablezSampleParameter(100); for (int i = 0; i < 1000; ++i) { - int64_t next_sample = 0; - HashtablezInfo* sample = SampleSlow(&next_sample); - EXPECT_GT(next_sample, 0); + SamplingState next_sample = {0, 0}; + HashtablezInfo* sample = SampleSlow(next_sample, test_element_size); + EXPECT_GT(next_sample.next_sample, 0); + EXPECT_EQ(next_sample.next_sample, next_sample.sample_stride); EXPECT_NE(sample, nullptr); UnsampleSlow(sample); } } TEST(HashtablezSamplerTest, LargeSampleParameter) { + const size_t test_element_size = 31; SetHashtablezEnabled(true); SetHashtablezSampleParameter(std::numeric_limits<int32_t>::max()); for (int i = 0; i < 1000; ++i) { - int64_t next_sample = 0; - HashtablezInfo* sample = SampleSlow(&next_sample); - EXPECT_GT(next_sample, 0); + SamplingState next_sample = {0, 0}; + HashtablezInfo* sample = SampleSlow(next_sample, test_element_size); + EXPECT_GT(next_sample.next_sample, 0); + EXPECT_EQ(next_sample.next_sample, next_sample.sample_stride); EXPECT_NE(sample, nullptr); UnsampleSlow(sample); } } TEST(HashtablezSamplerTest, Sample) { + const size_t test_element_size = 31; SetHashtablezEnabled(true); SetHashtablezSampleParameter(100); int64_t num_sampled = 0; int64_t total = 0; double sample_rate = 0.0; for (int i = 0; i < 1000000; ++i) { - HashtablezInfoHandle h = Sample(); + HashtablezInfoHandle h = Sample(test_element_size); ++total; if (HashtablezInfoHandlePeer::IsSampled(h)) { ++num_sampled; @@ -232,14 +277,17 @@ TEST(HashtablezSamplerTest, Sample) { } TEST(HashtablezSamplerTest, Handle) { - auto& sampler = HashtablezSampler::Global(); - HashtablezInfoHandle h(sampler.Register()); + auto& sampler = GlobalHashtablezSampler(); + const int64_t test_stride = 41; + const size_t test_element_size = 39; + HashtablezInfoHandle h(sampler.Register(test_stride, test_element_size)); auto* info = HashtablezInfoHandlePeer::GetInfo(&h); info->hashes_bitwise_and.store(0x12345678, std::memory_order_relaxed); bool found = false; sampler.Iterate([&](const HashtablezInfo& h) { if (&h == info) { + EXPECT_EQ(h.weight, test_stride); EXPECT_EQ(h.hashes_bitwise_and.load(), 0x12345678); found = true; } @@ -305,18 +353,20 @@ TEST(HashtablezSamplerTest, MultiThreaded) { ThreadPool pool(10); for (int i = 0; i < 10; ++i) { - pool.Schedule([&sampler, &stop]() { + const int64_t sampling_stride = 11 + i % 3; + const size_t elt_size = 10 + i % 2; + pool.Schedule([&sampler, &stop, sampling_stride, elt_size]() { std::random_device rd; std::mt19937 gen(rd()); std::vector<HashtablezInfo*> infoz; while (!stop.HasBeenNotified()) { if (infoz.empty()) { - infoz.push_back(sampler.Register()); + infoz.push_back(sampler.Register(sampling_stride, elt_size)); } switch (std::uniform_int_distribution<>(0, 2)(gen)) { case 0: { - infoz.push_back(sampler.Register()); + infoz.push_back(sampler.Register(sampling_stride, elt_size)); break; } case 1: { @@ -325,6 +375,7 @@ TEST(HashtablezSamplerTest, MultiThreaded) { HashtablezInfo* info = infoz[p]; infoz[p] = infoz.back(); infoz.pop_back(); + EXPECT_EQ(info->weight, sampling_stride); sampler.Unregister(info); break; } diff --git a/absl/container/internal/have_sse.h b/absl/container/internal/have_sse.h deleted file mode 100644 index e75e1a16..00000000 --- a/absl/container/internal/have_sse.h +++ /dev/null @@ -1,50 +0,0 @@ -// 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 -// -// https://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. -// -// Shared config probing for SSE instructions used in Swiss tables. -#ifndef ABSL_CONTAINER_INTERNAL_HAVE_SSE_H_ -#define ABSL_CONTAINER_INTERNAL_HAVE_SSE_H_ - -#ifndef ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 -#if defined(__SSE2__) || \ - (defined(_MSC_VER) && \ - (defined(_M_X64) || (defined(_M_IX86) && _M_IX86_FP >= 2))) -#define ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 1 -#else -#define ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 0 -#endif -#endif - -#ifndef ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSSE3 -#ifdef __SSSE3__ -#define ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSSE3 1 -#else -#define ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSSE3 0 -#endif -#endif - -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSSE3 && \ - !ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 -#error "Bad configuration!" -#endif - -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 -#include <emmintrin.h> -#endif - -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSSE3 -#include <tmmintrin.h> -#endif - -#endif // ABSL_CONTAINER_INTERNAL_HAVE_SSE_H_ diff --git a/absl/container/internal/inlined_vector.h b/absl/container/internal/inlined_vector.h index b8aec45b..54c92a01 100644 --- a/absl/container/internal/inlined_vector.h +++ b/absl/container/internal/inlined_vector.h @@ -21,8 +21,11 @@ #include <iterator> #include <limits> #include <memory> +#include <new> +#include <type_traits> #include <utility> +#include "absl/base/attributes.h" #include "absl/base/macros.h" #include "absl/container/internal/compressed_tuple.h" #include "absl/memory/memory.h" @@ -36,116 +39,145 @@ namespace inlined_vector_internal { // GCC does not deal very well with the below code #if !defined(__clang__) && defined(__GNUC__) #pragma GCC diagnostic push -#pragma GCC diagnostic ignored "-Wmaybe-uninitialized" +#pragma GCC diagnostic ignored "-Warray-bounds" #endif +template <typename A> +using AllocatorTraits = std::allocator_traits<A>; +template <typename A> +using ValueType = typename AllocatorTraits<A>::value_type; +template <typename A> +using SizeType = typename AllocatorTraits<A>::size_type; +template <typename A> +using Pointer = typename AllocatorTraits<A>::pointer; +template <typename A> +using ConstPointer = typename AllocatorTraits<A>::const_pointer; +template <typename A> +using SizeType = typename AllocatorTraits<A>::size_type; +template <typename A> +using DifferenceType = typename AllocatorTraits<A>::difference_type; +template <typename A> +using Reference = ValueType<A>&; +template <typename A> +using ConstReference = const ValueType<A>&; +template <typename A> +using Iterator = Pointer<A>; +template <typename A> +using ConstIterator = ConstPointer<A>; +template <typename A> +using ReverseIterator = typename std::reverse_iterator<Iterator<A>>; +template <typename A> +using ConstReverseIterator = typename std::reverse_iterator<ConstIterator<A>>; +template <typename A> +using MoveIterator = typename std::move_iterator<Iterator<A>>; + template <typename Iterator> using IsAtLeastForwardIterator = std::is_convertible< typename std::iterator_traits<Iterator>::iterator_category, std::forward_iterator_tag>; -template <typename AllocatorType, - typename ValueType = - typename absl::allocator_traits<AllocatorType>::value_type> +template <typename A> using IsMemcpyOk = - absl::conjunction<std::is_same<AllocatorType, std::allocator<ValueType>>, - absl::is_trivially_copy_constructible<ValueType>, - absl::is_trivially_copy_assignable<ValueType>, - absl::is_trivially_destructible<ValueType>>; - -template <typename AllocatorType, typename Pointer, typename SizeType> -void DestroyElements(AllocatorType* alloc_ptr, Pointer destroy_first, - SizeType destroy_size) { - using AllocatorTraits = absl::allocator_traits<AllocatorType>; - - if (destroy_first != nullptr) { - for (auto i = destroy_size; i != 0;) { + absl::conjunction<std::is_same<A, std::allocator<ValueType<A>>>, + absl::is_trivially_copy_constructible<ValueType<A>>, + absl::is_trivially_copy_assignable<ValueType<A>>, + absl::is_trivially_destructible<ValueType<A>>>; + +template <typename T> +struct TypeIdentity { + using type = T; +}; + +// Used for function arguments in template functions to prevent ADL by forcing +// callers to explicitly specify the template parameter. +template <typename T> +using NoTypeDeduction = typename TypeIdentity<T>::type; + +template <typename A, bool IsTriviallyDestructible = + absl::is_trivially_destructible<ValueType<A>>::value> +struct DestroyAdapter; + +template <typename A> +struct DestroyAdapter<A, /* IsTriviallyDestructible */ false> { + static void DestroyElements(A& allocator, Pointer<A> destroy_first, + SizeType<A> destroy_size) { + for (SizeType<A> i = destroy_size; i != 0;) { --i; - AllocatorTraits::destroy(*alloc_ptr, destroy_first + i); + AllocatorTraits<A>::destroy(allocator, destroy_first + i); } + } +}; -#if !defined(NDEBUG) - { - using ValueType = typename AllocatorTraits::value_type; - - // Overwrite unused memory with `0xab` so we can catch uninitialized - // usage. - // - // Cast to `void*` to tell the compiler that we don't care that we might - // be scribbling on a vtable pointer. - void* memory_ptr = destroy_first; - auto memory_size = destroy_size * sizeof(ValueType); - std::memset(memory_ptr, 0xab, memory_size); - } -#endif // !defined(NDEBUG) +template <typename A> +struct DestroyAdapter<A, /* IsTriviallyDestructible */ true> { + static void DestroyElements(A& allocator, Pointer<A> destroy_first, + SizeType<A> destroy_size) { + static_cast<void>(allocator); + static_cast<void>(destroy_first); + static_cast<void>(destroy_size); } -} +}; -// If kUseMemcpy is true, memcpy(dst, src, n); else do nothing. -// Useful to avoid compiler warnings when memcpy() is used for T values -// that are not trivially copyable in non-reachable code. -template <bool kUseMemcpy> -inline void MemcpyIfAllowed(void* dst, const void* src, size_t n); +template <typename A> +struct Allocation { + Pointer<A> data; + SizeType<A> capacity; +}; -// memcpy when allowed. -template <> -inline void MemcpyIfAllowed<true>(void* dst, const void* src, size_t n) { - memcpy(dst, src, n); -} +template <typename A, + bool IsOverAligned = + (alignof(ValueType<A>) > ABSL_INTERNAL_DEFAULT_NEW_ALIGNMENT)> +struct MallocAdapter { + static Allocation<A> Allocate(A& allocator, SizeType<A> requested_capacity) { + return {AllocatorTraits<A>::allocate(allocator, requested_capacity), + requested_capacity}; + } -// Do nothing for types that are not memcpy-able. This function is only -// called from non-reachable branches. -template <> -inline void MemcpyIfAllowed<false>(void*, const void*, size_t) {} + static void Deallocate(A& allocator, Pointer<A> pointer, + SizeType<A> capacity) { + AllocatorTraits<A>::deallocate(allocator, pointer, capacity); + } +}; -template <typename AllocatorType, typename Pointer, typename ValueAdapter, - typename SizeType> -void ConstructElements(AllocatorType* alloc_ptr, Pointer construct_first, - ValueAdapter* values_ptr, SizeType construct_size) { - for (SizeType i = 0; i < construct_size; ++i) { - ABSL_INTERNAL_TRY { - values_ptr->ConstructNext(alloc_ptr, construct_first + i); - } +template <typename A, typename ValueAdapter> +void ConstructElements(NoTypeDeduction<A>& allocator, + Pointer<A> construct_first, ValueAdapter& values, + SizeType<A> construct_size) { + for (SizeType<A> i = 0; i < construct_size; ++i) { + ABSL_INTERNAL_TRY { values.ConstructNext(allocator, construct_first + i); } ABSL_INTERNAL_CATCH_ANY { - inlined_vector_internal::DestroyElements(alloc_ptr, construct_first, i); + DestroyAdapter<A>::DestroyElements(allocator, construct_first, i); ABSL_INTERNAL_RETHROW; } } } -template <typename Pointer, typename ValueAdapter, typename SizeType> -void AssignElements(Pointer assign_first, ValueAdapter* values_ptr, - SizeType assign_size) { - for (SizeType i = 0; i < assign_size; ++i) { - values_ptr->AssignNext(assign_first + i); +template <typename A, typename ValueAdapter> +void AssignElements(Pointer<A> assign_first, ValueAdapter& values, + SizeType<A> assign_size) { + for (SizeType<A> i = 0; i < assign_size; ++i) { + values.AssignNext(assign_first + i); } } -template <typename AllocatorType> +template <typename A> struct StorageView { - using AllocatorTraits = absl::allocator_traits<AllocatorType>; - using Pointer = typename AllocatorTraits::pointer; - using SizeType = typename AllocatorTraits::size_type; - - Pointer data; - SizeType size; - SizeType capacity; + Pointer<A> data; + SizeType<A> size; + SizeType<A> capacity; }; -template <typename AllocatorType, typename Iterator> +template <typename A, typename Iterator> class IteratorValueAdapter { - using AllocatorTraits = absl::allocator_traits<AllocatorType>; - using Pointer = typename AllocatorTraits::pointer; - public: explicit IteratorValueAdapter(const Iterator& it) : it_(it) {} - void ConstructNext(AllocatorType* alloc_ptr, Pointer construct_at) { - AllocatorTraits::construct(*alloc_ptr, construct_at, *it_); + void ConstructNext(A& allocator, Pointer<A> construct_at) { + AllocatorTraits<A>::construct(allocator, construct_at, *it_); ++it_; } - void AssignNext(Pointer assign_at) { + void AssignNext(Pointer<A> assign_at) { *assign_at = *it_; ++it_; } @@ -154,166 +186,123 @@ class IteratorValueAdapter { Iterator it_; }; -template <typename AllocatorType> +template <typename A> class CopyValueAdapter { - using AllocatorTraits = absl::allocator_traits<AllocatorType>; - using ValueType = typename AllocatorTraits::value_type; - using Pointer = typename AllocatorTraits::pointer; - using ConstPointer = typename AllocatorTraits::const_pointer; - public: - explicit CopyValueAdapter(const ValueType& v) : ptr_(std::addressof(v)) {} + explicit CopyValueAdapter(ConstPointer<A> p) : ptr_(p) {} - void ConstructNext(AllocatorType* alloc_ptr, Pointer construct_at) { - AllocatorTraits::construct(*alloc_ptr, construct_at, *ptr_); + void ConstructNext(A& allocator, Pointer<A> construct_at) { + AllocatorTraits<A>::construct(allocator, construct_at, *ptr_); } - void AssignNext(Pointer assign_at) { *assign_at = *ptr_; } + void AssignNext(Pointer<A> assign_at) { *assign_at = *ptr_; } private: - ConstPointer ptr_; + ConstPointer<A> ptr_; }; -template <typename AllocatorType> +template <typename A> class DefaultValueAdapter { - using AllocatorTraits = absl::allocator_traits<AllocatorType>; - using ValueType = typename AllocatorTraits::value_type; - using Pointer = typename AllocatorTraits::pointer; - public: explicit DefaultValueAdapter() {} - void ConstructNext(AllocatorType* alloc_ptr, Pointer construct_at) { - AllocatorTraits::construct(*alloc_ptr, construct_at); + void ConstructNext(A& allocator, Pointer<A> construct_at) { + AllocatorTraits<A>::construct(allocator, construct_at); } - void AssignNext(Pointer assign_at) { *assign_at = ValueType(); } + void AssignNext(Pointer<A> assign_at) { *assign_at = ValueType<A>(); } }; -template <typename AllocatorType> +template <typename A> class AllocationTransaction { - using AllocatorTraits = absl::allocator_traits<AllocatorType>; - using Pointer = typename AllocatorTraits::pointer; - using SizeType = typename AllocatorTraits::size_type; - public: - explicit AllocationTransaction(AllocatorType* alloc_ptr) - : alloc_data_(*alloc_ptr, nullptr) {} + explicit AllocationTransaction(A& allocator) + : allocator_data_(allocator, nullptr), capacity_(0) {} ~AllocationTransaction() { if (DidAllocate()) { - AllocatorTraits::deallocate(GetAllocator(), GetData(), GetCapacity()); + MallocAdapter<A>::Deallocate(GetAllocator(), GetData(), GetCapacity()); } } AllocationTransaction(const AllocationTransaction&) = delete; void operator=(const AllocationTransaction&) = delete; - AllocatorType& GetAllocator() { return alloc_data_.template get<0>(); } - Pointer& GetData() { return alloc_data_.template get<1>(); } - SizeType& GetCapacity() { return capacity_; } + A& GetAllocator() { return allocator_data_.template get<0>(); } + Pointer<A>& GetData() { return allocator_data_.template get<1>(); } + SizeType<A>& GetCapacity() { return capacity_; } bool DidAllocate() { return GetData() != nullptr; } - Pointer Allocate(SizeType capacity) { - GetData() = AllocatorTraits::allocate(GetAllocator(), capacity); - GetCapacity() = capacity; - return GetData(); + + Pointer<A> Allocate(SizeType<A> requested_capacity) { + Allocation<A> result = + MallocAdapter<A>::Allocate(GetAllocator(), requested_capacity); + GetData() = result.data; + GetCapacity() = result.capacity; + return result.data; } + ABSL_MUST_USE_RESULT Allocation<A> Release() && { + Allocation<A> result = {GetData(), GetCapacity()}; + Reset(); + return result; + } + + private: void Reset() { GetData() = nullptr; GetCapacity() = 0; } - private: - container_internal::CompressedTuple<AllocatorType, Pointer> alloc_data_; - SizeType capacity_ = 0; + container_internal::CompressedTuple<A, Pointer<A>> allocator_data_; + SizeType<A> capacity_; }; -template <typename AllocatorType> +template <typename A> class ConstructionTransaction { - using AllocatorTraits = absl::allocator_traits<AllocatorType>; - using Pointer = typename AllocatorTraits::pointer; - using SizeType = typename AllocatorTraits::size_type; - public: - explicit ConstructionTransaction(AllocatorType* alloc_ptr) - : alloc_data_(*alloc_ptr, nullptr) {} + explicit ConstructionTransaction(A& allocator) + : allocator_data_(allocator, nullptr), size_(0) {} ~ConstructionTransaction() { if (DidConstruct()) { - inlined_vector_internal::DestroyElements(std::addressof(GetAllocator()), - GetData(), GetSize()); + DestroyAdapter<A>::DestroyElements(GetAllocator(), GetData(), GetSize()); } } ConstructionTransaction(const ConstructionTransaction&) = delete; void operator=(const ConstructionTransaction&) = delete; - AllocatorType& GetAllocator() { return alloc_data_.template get<0>(); } - Pointer& GetData() { return alloc_data_.template get<1>(); } - SizeType& GetSize() { return size_; } + A& GetAllocator() { return allocator_data_.template get<0>(); } + Pointer<A>& GetData() { return allocator_data_.template get<1>(); } + SizeType<A>& GetSize() { return size_; } bool DidConstruct() { return GetData() != nullptr; } template <typename ValueAdapter> - void Construct(Pointer data, ValueAdapter* values_ptr, SizeType size) { - inlined_vector_internal::ConstructElements(std::addressof(GetAllocator()), - data, values_ptr, size); + void Construct(Pointer<A> data, ValueAdapter& values, SizeType<A> size) { + ConstructElements<A>(GetAllocator(), data, values, size); GetData() = data; GetSize() = size; } - void Commit() { + void Commit() && { GetData() = nullptr; GetSize() = 0; } private: - container_internal::CompressedTuple<AllocatorType, Pointer> alloc_data_; - SizeType size_ = 0; + container_internal::CompressedTuple<A, Pointer<A>> allocator_data_; + SizeType<A> size_; }; template <typename T, size_t N, typename A> class Storage { public: - using AllocatorTraits = absl::allocator_traits<A>; - using allocator_type = typename AllocatorTraits::allocator_type; - using value_type = typename AllocatorTraits::value_type; - using pointer = typename AllocatorTraits::pointer; - using const_pointer = typename AllocatorTraits::const_pointer; - using size_type = typename AllocatorTraits::size_type; - using difference_type = typename AllocatorTraits::difference_type; - - using reference = value_type&; - using const_reference = const value_type&; - using RValueReference = value_type&&; - using iterator = pointer; - using const_iterator = const_pointer; - using reverse_iterator = std::reverse_iterator<iterator>; - using const_reverse_iterator = std::reverse_iterator<const_iterator>; - using MoveIterator = std::move_iterator<iterator>; - using IsMemcpyOk = inlined_vector_internal::IsMemcpyOk<allocator_type>; - - using StorageView = inlined_vector_internal::StorageView<allocator_type>; - - template <typename Iterator> - using IteratorValueAdapter = - inlined_vector_internal::IteratorValueAdapter<allocator_type, Iterator>; - using CopyValueAdapter = - inlined_vector_internal::CopyValueAdapter<allocator_type>; - using DefaultValueAdapter = - inlined_vector_internal::DefaultValueAdapter<allocator_type>; - - using AllocationTransaction = - inlined_vector_internal::AllocationTransaction<allocator_type>; - using ConstructionTransaction = - inlined_vector_internal::ConstructionTransaction<allocator_type>; - - static size_type NextCapacity(size_type current_capacity) { + static SizeType<A> NextCapacity(SizeType<A> current_capacity) { return current_capacity * 2; } - static size_type ComputeCapacity(size_type current_capacity, - size_type requested_capacity) { + static SizeType<A> ComputeCapacity(SizeType<A> current_capacity, + SizeType<A> requested_capacity) { return (std::max)(NextCapacity(current_capacity), requested_capacity); } @@ -321,15 +310,15 @@ class Storage { // Storage Constructors and Destructor // --------------------------------------------------------------------------- - Storage() : metadata_(allocator_type(), /* size and is_allocated */ 0) {} + Storage() : metadata_(A(), /* size and is_allocated */ 0u) {} - explicit Storage(const allocator_type& alloc) - : metadata_(alloc, /* size and is_allocated */ 0) {} + explicit Storage(const A& allocator) + : metadata_(allocator, /* size and is_allocated */ 0u) {} ~Storage() { if (GetSizeAndIsAllocated() == 0) { // Empty and not allocated; nothing to do. - } else if (IsMemcpyOk::value) { + } else if (IsMemcpyOk<A>::value) { // No destructors need to be run; just deallocate if necessary. DeallocateIfAllocated(); } else { @@ -341,52 +330,48 @@ class Storage { // Storage Member Accessors // --------------------------------------------------------------------------- - size_type& GetSizeAndIsAllocated() { return metadata_.template get<1>(); } + SizeType<A>& GetSizeAndIsAllocated() { return metadata_.template get<1>(); } - const size_type& GetSizeAndIsAllocated() const { + const SizeType<A>& GetSizeAndIsAllocated() const { return metadata_.template get<1>(); } - size_type GetSize() const { return GetSizeAndIsAllocated() >> 1; } + SizeType<A> GetSize() const { return GetSizeAndIsAllocated() >> 1; } bool GetIsAllocated() const { return GetSizeAndIsAllocated() & 1; } - pointer GetAllocatedData() { return data_.allocated.allocated_data; } + Pointer<A> GetAllocatedData() { return data_.allocated.allocated_data; } - const_pointer GetAllocatedData() const { + ConstPointer<A> GetAllocatedData() const { return data_.allocated.allocated_data; } - pointer GetInlinedData() { - return reinterpret_cast<pointer>( + Pointer<A> GetInlinedData() { + return reinterpret_cast<Pointer<A>>( std::addressof(data_.inlined.inlined_data[0])); } - const_pointer GetInlinedData() const { - return reinterpret_cast<const_pointer>( + ConstPointer<A> GetInlinedData() const { + return reinterpret_cast<ConstPointer<A>>( std::addressof(data_.inlined.inlined_data[0])); } - size_type GetAllocatedCapacity() const { + SizeType<A> GetAllocatedCapacity() const { return data_.allocated.allocated_capacity; } - size_type GetInlinedCapacity() const { return static_cast<size_type>(N); } + SizeType<A> GetInlinedCapacity() const { return static_cast<SizeType<A>>(N); } - StorageView MakeStorageView() { - return GetIsAllocated() - ? StorageView{GetAllocatedData(), GetSize(), - GetAllocatedCapacity()} - : StorageView{GetInlinedData(), GetSize(), GetInlinedCapacity()}; + StorageView<A> MakeStorageView() { + return GetIsAllocated() ? StorageView<A>{GetAllocatedData(), GetSize(), + GetAllocatedCapacity()} + : StorageView<A>{GetInlinedData(), GetSize(), + GetInlinedCapacity()}; } - allocator_type* GetAllocPtr() { - return std::addressof(metadata_.template get<0>()); - } + A& GetAllocator() { return metadata_.template get<0>(); } - const allocator_type* GetAllocPtr() const { - return std::addressof(metadata_.template get<0>()); - } + const A& GetAllocator() const { return metadata_.template get<0>(); } // --------------------------------------------------------------------------- // Storage Member Mutators @@ -395,74 +380,68 @@ class Storage { ABSL_ATTRIBUTE_NOINLINE void InitFrom(const Storage& other); template <typename ValueAdapter> - void Initialize(ValueAdapter values, size_type new_size); + void Initialize(ValueAdapter values, SizeType<A> new_size); template <typename ValueAdapter> - void Assign(ValueAdapter values, size_type new_size); + void Assign(ValueAdapter values, SizeType<A> new_size); template <typename ValueAdapter> - void Resize(ValueAdapter values, size_type new_size); + void Resize(ValueAdapter values, SizeType<A> new_size); template <typename ValueAdapter> - iterator Insert(const_iterator pos, ValueAdapter values, - size_type insert_count); + Iterator<A> Insert(ConstIterator<A> pos, ValueAdapter values, + SizeType<A> insert_count); template <typename... Args> - reference EmplaceBack(Args&&... args); + Reference<A> EmplaceBack(Args&&... args); - iterator Erase(const_iterator from, const_iterator to); + Iterator<A> Erase(ConstIterator<A> from, ConstIterator<A> to); - void Reserve(size_type requested_capacity); + void Reserve(SizeType<A> requested_capacity); void ShrinkToFit(); void Swap(Storage* other_storage_ptr); void SetIsAllocated() { - GetSizeAndIsAllocated() |= static_cast<size_type>(1); + GetSizeAndIsAllocated() |= static_cast<SizeType<A>>(1); } void UnsetIsAllocated() { - GetSizeAndIsAllocated() &= ((std::numeric_limits<size_type>::max)() - 1); + GetSizeAndIsAllocated() &= ((std::numeric_limits<SizeType<A>>::max)() - 1); } - void SetSize(size_type size) { + void SetSize(SizeType<A> size) { GetSizeAndIsAllocated() = - (size << 1) | static_cast<size_type>(GetIsAllocated()); + (size << 1) | static_cast<SizeType<A>>(GetIsAllocated()); } - void SetAllocatedSize(size_type size) { - GetSizeAndIsAllocated() = (size << 1) | static_cast<size_type>(1); + void SetAllocatedSize(SizeType<A> size) { + GetSizeAndIsAllocated() = (size << 1) | static_cast<SizeType<A>>(1); } - void SetInlinedSize(size_type size) { - GetSizeAndIsAllocated() = size << static_cast<size_type>(1); + void SetInlinedSize(SizeType<A> size) { + GetSizeAndIsAllocated() = size << static_cast<SizeType<A>>(1); } - void AddSize(size_type count) { - GetSizeAndIsAllocated() += count << static_cast<size_type>(1); + void AddSize(SizeType<A> count) { + GetSizeAndIsAllocated() += count << static_cast<SizeType<A>>(1); } - void SubtractSize(size_type count) { - assert(count <= GetSize()); + void SubtractSize(SizeType<A> count) { + ABSL_HARDENING_ASSERT(count <= GetSize()); - GetSizeAndIsAllocated() -= count << static_cast<size_type>(1); + GetSizeAndIsAllocated() -= count << static_cast<SizeType<A>>(1); } - void SetAllocatedData(pointer data, size_type capacity) { - data_.allocated.allocated_data = data; - data_.allocated.allocated_capacity = capacity; - } - - void AcquireAllocatedData(AllocationTransaction* allocation_tx_ptr) { - SetAllocatedData(allocation_tx_ptr->GetData(), - allocation_tx_ptr->GetCapacity()); - - allocation_tx_ptr->Reset(); + void SetAllocation(Allocation<A> allocation) { + data_.allocated.allocated_data = allocation.data; + data_.allocated.allocated_capacity = allocation.capacity; } void MemcpyFrom(const Storage& other_storage) { - assert(IsMemcpyOk::value || other_storage.GetIsAllocated()); + ABSL_HARDENING_ASSERT(IsMemcpyOk<A>::value || + other_storage.GetIsAllocated()); GetSizeAndIsAllocated() = other_storage.GetSizeAndIsAllocated(); data_ = other_storage.data_; @@ -470,24 +449,23 @@ class Storage { void DeallocateIfAllocated() { if (GetIsAllocated()) { - AllocatorTraits::deallocate(*GetAllocPtr(), GetAllocatedData(), - GetAllocatedCapacity()); + MallocAdapter<A>::Deallocate(GetAllocator(), GetAllocatedData(), + GetAllocatedCapacity()); } } private: ABSL_ATTRIBUTE_NOINLINE void DestroyContents(); - using Metadata = - container_internal::CompressedTuple<allocator_type, size_type>; + using Metadata = container_internal::CompressedTuple<A, SizeType<A>>; struct Allocated { - pointer allocated_data; - size_type allocated_capacity; + Pointer<A> allocated_data; + SizeType<A> allocated_capacity; }; struct Inlined { - alignas(value_type) char inlined_data[sizeof(value_type[N])]; + alignas(ValueType<A>) char inlined_data[sizeof(ValueType<A>[N])]; }; union Data { @@ -496,7 +474,7 @@ class Storage { }; template <typename... Args> - ABSL_ATTRIBUTE_NOINLINE reference EmplaceBackSlow(Args&&... args); + ABSL_ATTRIBUTE_NOINLINE Reference<A> EmplaceBackSlow(Args&&... args); Metadata metadata_; Data data_; @@ -504,17 +482,17 @@ class Storage { template <typename T, size_t N, typename A> void Storage<T, N, A>::DestroyContents() { - pointer data = GetIsAllocated() ? GetAllocatedData() : GetInlinedData(); - inlined_vector_internal::DestroyElements(GetAllocPtr(), data, GetSize()); + Pointer<A> data = GetIsAllocated() ? GetAllocatedData() : GetInlinedData(); + DestroyAdapter<A>::DestroyElements(GetAllocator(), data, GetSize()); DeallocateIfAllocated(); } template <typename T, size_t N, typename A> void Storage<T, N, A>::InitFrom(const Storage& other) { - const auto n = other.GetSize(); - assert(n > 0); // Empty sources handled handled in caller. - const_pointer src; - pointer dst; + const SizeType<A> n = other.GetSize(); + ABSL_HARDENING_ASSERT(n > 0); // Empty sources handled handled in caller. + ConstPointer<A> src; + Pointer<A> dst; if (!other.GetIsAllocated()) { dst = GetInlinedData(); src = other.GetInlinedData(); @@ -522,43 +500,48 @@ void Storage<T, N, A>::InitFrom(const Storage& other) { // Because this is only called from the `InlinedVector` constructors, it's // safe to take on the allocation with size `0`. If `ConstructElements(...)` // throws, deallocation will be automatically handled by `~Storage()`. - size_type new_capacity = ComputeCapacity(GetInlinedCapacity(), n); - dst = AllocatorTraits::allocate(*GetAllocPtr(), new_capacity); - SetAllocatedData(dst, new_capacity); + SizeType<A> requested_capacity = ComputeCapacity(GetInlinedCapacity(), n); + Allocation<A> allocation = + MallocAdapter<A>::Allocate(GetAllocator(), requested_capacity); + SetAllocation(allocation); + dst = allocation.data; src = other.GetAllocatedData(); } - if (IsMemcpyOk::value) { - MemcpyIfAllowed<IsMemcpyOk::value>(dst, src, sizeof(dst[0]) * n); + if (IsMemcpyOk<A>::value) { + std::memcpy(reinterpret_cast<char*>(dst), + reinterpret_cast<const char*>(src), n * sizeof(ValueType<A>)); } else { - auto values = IteratorValueAdapter<const_pointer>(src); - inlined_vector_internal::ConstructElements(GetAllocPtr(), dst, &values, n); + auto values = IteratorValueAdapter<A, ConstPointer<A>>(src); + ConstructElements<A>(GetAllocator(), dst, values, n); } GetSizeAndIsAllocated() = other.GetSizeAndIsAllocated(); } template <typename T, size_t N, typename A> template <typename ValueAdapter> -auto Storage<T, N, A>::Initialize(ValueAdapter values, size_type new_size) +auto Storage<T, N, A>::Initialize(ValueAdapter values, SizeType<A> new_size) -> void { // Only callable from constructors! - assert(!GetIsAllocated()); - assert(GetSize() == 0); + ABSL_HARDENING_ASSERT(!GetIsAllocated()); + ABSL_HARDENING_ASSERT(GetSize() == 0); - pointer construct_data; + Pointer<A> construct_data; if (new_size > GetInlinedCapacity()) { // Because this is only called from the `InlinedVector` constructors, it's // safe to take on the allocation with size `0`. If `ConstructElements(...)` // throws, deallocation will be automatically handled by `~Storage()`. - size_type new_capacity = ComputeCapacity(GetInlinedCapacity(), new_size); - construct_data = AllocatorTraits::allocate(*GetAllocPtr(), new_capacity); - SetAllocatedData(construct_data, new_capacity); + SizeType<A> requested_capacity = + ComputeCapacity(GetInlinedCapacity(), new_size); + Allocation<A> allocation = + MallocAdapter<A>::Allocate(GetAllocator(), requested_capacity); + construct_data = allocation.data; + SetAllocation(allocation); SetIsAllocated(); } else { construct_data = GetInlinedData(); } - inlined_vector_internal::ConstructElements(GetAllocPtr(), construct_data, - &values, new_size); + ConstructElements<A>(GetAllocator(), construct_data, values, new_size); // Since the initial size was guaranteed to be `0` and the allocated bit is // already correct for either case, *adding* `new_size` gives us the correct @@ -568,18 +551,20 @@ auto Storage<T, N, A>::Initialize(ValueAdapter values, size_type new_size) template <typename T, size_t N, typename A> template <typename ValueAdapter> -auto Storage<T, N, A>::Assign(ValueAdapter values, size_type new_size) -> void { - StorageView storage_view = MakeStorageView(); +auto Storage<T, N, A>::Assign(ValueAdapter values, SizeType<A> new_size) + -> void { + StorageView<A> storage_view = MakeStorageView(); - AllocationTransaction allocation_tx(GetAllocPtr()); + AllocationTransaction<A> allocation_tx(GetAllocator()); - absl::Span<value_type> assign_loop; - absl::Span<value_type> construct_loop; - absl::Span<value_type> destroy_loop; + absl::Span<ValueType<A>> assign_loop; + absl::Span<ValueType<A>> construct_loop; + absl::Span<ValueType<A>> destroy_loop; if (new_size > storage_view.capacity) { - size_type new_capacity = ComputeCapacity(storage_view.capacity, new_size); - construct_loop = {allocation_tx.Allocate(new_capacity), new_size}; + SizeType<A> requested_capacity = + ComputeCapacity(storage_view.capacity, new_size); + construct_loop = {allocation_tx.Allocate(requested_capacity), new_size}; destroy_loop = {storage_view.data, storage_view.size}; } else if (new_size > storage_view.size) { assign_loop = {storage_view.data, storage_view.size}; @@ -590,18 +575,17 @@ auto Storage<T, N, A>::Assign(ValueAdapter values, size_type new_size) -> void { destroy_loop = {storage_view.data + new_size, storage_view.size - new_size}; } - inlined_vector_internal::AssignElements(assign_loop.data(), &values, - assign_loop.size()); + AssignElements<A>(assign_loop.data(), values, assign_loop.size()); - inlined_vector_internal::ConstructElements( - GetAllocPtr(), construct_loop.data(), &values, construct_loop.size()); + ConstructElements<A>(GetAllocator(), construct_loop.data(), values, + construct_loop.size()); - inlined_vector_internal::DestroyElements(GetAllocPtr(), destroy_loop.data(), - destroy_loop.size()); + DestroyAdapter<A>::DestroyElements(GetAllocator(), destroy_loop.data(), + destroy_loop.size()); if (allocation_tx.DidAllocate()) { DeallocateIfAllocated(); - AcquireAllocatedData(&allocation_tx); + SetAllocation(std::move(allocation_tx).Release()); SetIsAllocated(); } @@ -610,42 +594,42 @@ auto Storage<T, N, A>::Assign(ValueAdapter values, size_type new_size) -> void { template <typename T, size_t N, typename A> template <typename ValueAdapter> -auto Storage<T, N, A>::Resize(ValueAdapter values, size_type new_size) -> void { - StorageView storage_view = MakeStorageView(); - auto* const base = storage_view.data; - const size_type size = storage_view.size; - auto* alloc = GetAllocPtr(); +auto Storage<T, N, A>::Resize(ValueAdapter values, SizeType<A> new_size) + -> void { + StorageView<A> storage_view = MakeStorageView(); + Pointer<A> const base = storage_view.data; + const SizeType<A> size = storage_view.size; + A& alloc = GetAllocator(); if (new_size <= size) { // Destroy extra old elements. - inlined_vector_internal::DestroyElements(alloc, base + new_size, - size - new_size); + DestroyAdapter<A>::DestroyElements(alloc, base + new_size, size - new_size); } else if (new_size <= storage_view.capacity) { // Construct new elements in place. - inlined_vector_internal::ConstructElements(alloc, base + size, &values, - new_size - size); + ConstructElements<A>(alloc, base + size, values, new_size - size); } else { // Steps: // a. Allocate new backing store. // b. Construct new elements in new backing store. - // c. Move existing elements from old backing store to now. + // c. Move existing elements from old backing store to new backing store. // d. Destroy all elements in old backing store. // Use transactional wrappers for the first two steps so we can roll // back if necessary due to exceptions. - AllocationTransaction allocation_tx(alloc); - size_type new_capacity = ComputeCapacity(storage_view.capacity, new_size); - pointer new_data = allocation_tx.Allocate(new_capacity); + AllocationTransaction<A> allocation_tx(alloc); + SizeType<A> requested_capacity = + ComputeCapacity(storage_view.capacity, new_size); + Pointer<A> new_data = allocation_tx.Allocate(requested_capacity); - ConstructionTransaction construction_tx(alloc); - construction_tx.Construct(new_data + size, &values, new_size - size); + ConstructionTransaction<A> construction_tx(alloc); + construction_tx.Construct(new_data + size, values, new_size - size); - IteratorValueAdapter<MoveIterator> move_values((MoveIterator(base))); - inlined_vector_internal::ConstructElements(alloc, new_data, &move_values, - size); + IteratorValueAdapter<A, MoveIterator<A>> move_values( + (MoveIterator<A>(base))); + ConstructElements<A>(alloc, new_data, move_values, size); - inlined_vector_internal::DestroyElements(alloc, base, size); - construction_tx.Commit(); + DestroyAdapter<A>::DestroyElements(alloc, base, size); + std::move(construction_tx).Commit(); DeallocateIfAllocated(); - AcquireAllocatedData(&allocation_tx); + SetAllocation(std::move(allocation_tx).Release()); SetIsAllocated(); } SetSize(new_size); @@ -653,76 +637,77 @@ auto Storage<T, N, A>::Resize(ValueAdapter values, size_type new_size) -> void { template <typename T, size_t N, typename A> template <typename ValueAdapter> -auto Storage<T, N, A>::Insert(const_iterator pos, ValueAdapter values, - size_type insert_count) -> iterator { - StorageView storage_view = MakeStorageView(); +auto Storage<T, N, A>::Insert(ConstIterator<A> pos, ValueAdapter values, + SizeType<A> insert_count) -> Iterator<A> { + StorageView<A> storage_view = MakeStorageView(); - size_type insert_index = - std::distance(const_iterator(storage_view.data), pos); - size_type insert_end_index = insert_index + insert_count; - size_type new_size = storage_view.size + insert_count; + SizeType<A> insert_index = + std::distance(ConstIterator<A>(storage_view.data), pos); + SizeType<A> insert_end_index = insert_index + insert_count; + SizeType<A> new_size = storage_view.size + insert_count; if (new_size > storage_view.capacity) { - AllocationTransaction allocation_tx(GetAllocPtr()); - ConstructionTransaction construction_tx(GetAllocPtr()); - ConstructionTransaction move_construciton_tx(GetAllocPtr()); + AllocationTransaction<A> allocation_tx(GetAllocator()); + ConstructionTransaction<A> construction_tx(GetAllocator()); + ConstructionTransaction<A> move_construction_tx(GetAllocator()); - IteratorValueAdapter<MoveIterator> move_values( - MoveIterator(storage_view.data)); + IteratorValueAdapter<A, MoveIterator<A>> move_values( + MoveIterator<A>(storage_view.data)); - size_type new_capacity = ComputeCapacity(storage_view.capacity, new_size); - pointer new_data = allocation_tx.Allocate(new_capacity); + SizeType<A> requested_capacity = + ComputeCapacity(storage_view.capacity, new_size); + Pointer<A> new_data = allocation_tx.Allocate(requested_capacity); - construction_tx.Construct(new_data + insert_index, &values, insert_count); + construction_tx.Construct(new_data + insert_index, values, insert_count); - move_construciton_tx.Construct(new_data, &move_values, insert_index); + move_construction_tx.Construct(new_data, move_values, insert_index); - inlined_vector_internal::ConstructElements( - GetAllocPtr(), new_data + insert_end_index, &move_values, - storage_view.size - insert_index); + ConstructElements<A>(GetAllocator(), new_data + insert_end_index, + move_values, storage_view.size - insert_index); - inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data, - storage_view.size); + DestroyAdapter<A>::DestroyElements(GetAllocator(), storage_view.data, + storage_view.size); - construction_tx.Commit(); - move_construciton_tx.Commit(); + std::move(construction_tx).Commit(); + std::move(move_construction_tx).Commit(); DeallocateIfAllocated(); - AcquireAllocatedData(&allocation_tx); + SetAllocation(std::move(allocation_tx).Release()); SetAllocatedSize(new_size); - return iterator(new_data + insert_index); + return Iterator<A>(new_data + insert_index); } else { - size_type move_construction_destination_index = + SizeType<A> move_construction_destination_index = (std::max)(insert_end_index, storage_view.size); - ConstructionTransaction move_construction_tx(GetAllocPtr()); + ConstructionTransaction<A> move_construction_tx(GetAllocator()); - IteratorValueAdapter<MoveIterator> move_construction_values( - MoveIterator(storage_view.data + - (move_construction_destination_index - insert_count))); - absl::Span<value_type> move_construction = { + IteratorValueAdapter<A, MoveIterator<A>> move_construction_values( + MoveIterator<A>(storage_view.data + + (move_construction_destination_index - insert_count))); + absl::Span<ValueType<A>> move_construction = { storage_view.data + move_construction_destination_index, new_size - move_construction_destination_index}; - pointer move_assignment_values = storage_view.data + insert_index; - absl::Span<value_type> move_assignment = { + Pointer<A> move_assignment_values = storage_view.data + insert_index; + absl::Span<ValueType<A>> move_assignment = { storage_view.data + insert_end_index, move_construction_destination_index - insert_end_index}; - absl::Span<value_type> insert_assignment = {move_assignment_values, - move_construction.size()}; + absl::Span<ValueType<A>> insert_assignment = {move_assignment_values, + move_construction.size()}; - absl::Span<value_type> insert_construction = { + absl::Span<ValueType<A>> insert_construction = { insert_assignment.data() + insert_assignment.size(), insert_count - insert_assignment.size()}; move_construction_tx.Construct(move_construction.data(), - &move_construction_values, + move_construction_values, move_construction.size()); - for (pointer destination = move_assignment.data() + move_assignment.size(), - last_destination = move_assignment.data(), - source = move_assignment_values + move_assignment.size(); + for (Pointer<A> + destination = move_assignment.data() + move_assignment.size(), + last_destination = move_assignment.data(), + source = move_assignment_values + move_assignment.size(); ;) { --destination; --source; @@ -730,30 +715,29 @@ auto Storage<T, N, A>::Insert(const_iterator pos, ValueAdapter values, *destination = std::move(*source); } - inlined_vector_internal::AssignElements(insert_assignment.data(), &values, - insert_assignment.size()); + AssignElements<A>(insert_assignment.data(), values, + insert_assignment.size()); - inlined_vector_internal::ConstructElements( - GetAllocPtr(), insert_construction.data(), &values, - insert_construction.size()); + ConstructElements<A>(GetAllocator(), insert_construction.data(), values, + insert_construction.size()); - move_construction_tx.Commit(); + std::move(move_construction_tx).Commit(); AddSize(insert_count); - return iterator(storage_view.data + insert_index); + return Iterator<A>(storage_view.data + insert_index); } } template <typename T, size_t N, typename A> template <typename... Args> -auto Storage<T, N, A>::EmplaceBack(Args&&... args) -> reference { - StorageView storage_view = MakeStorageView(); - const auto n = storage_view.size; +auto Storage<T, N, A>::EmplaceBack(Args&&... args) -> Reference<A> { + StorageView<A> storage_view = MakeStorageView(); + const SizeType<A> n = storage_view.size; if (ABSL_PREDICT_TRUE(n != storage_view.capacity)) { // Fast path; new element fits. - pointer last_ptr = storage_view.data + n; - AllocatorTraits::construct(*GetAllocPtr(), last_ptr, - std::forward<Args>(args)...); + Pointer<A> last_ptr = storage_view.data + n; + AllocatorTraits<A>::construct(GetAllocator(), last_ptr, + std::forward<Args>(args)...); AddSize(1); return *last_ptr; } @@ -763,130 +747,132 @@ auto Storage<T, N, A>::EmplaceBack(Args&&... args) -> reference { template <typename T, size_t N, typename A> template <typename... Args> -auto Storage<T, N, A>::EmplaceBackSlow(Args&&... args) -> reference { - StorageView storage_view = MakeStorageView(); - AllocationTransaction allocation_tx(GetAllocPtr()); - IteratorValueAdapter<MoveIterator> move_values( - MoveIterator(storage_view.data)); - size_type new_capacity = NextCapacity(storage_view.capacity); - pointer construct_data = allocation_tx.Allocate(new_capacity); - pointer last_ptr = construct_data + storage_view.size; +auto Storage<T, N, A>::EmplaceBackSlow(Args&&... args) -> Reference<A> { + StorageView<A> storage_view = MakeStorageView(); + AllocationTransaction<A> allocation_tx(GetAllocator()); + IteratorValueAdapter<A, MoveIterator<A>> move_values( + MoveIterator<A>(storage_view.data)); + SizeType<A> requested_capacity = NextCapacity(storage_view.capacity); + Pointer<A> construct_data = allocation_tx.Allocate(requested_capacity); + Pointer<A> last_ptr = construct_data + storage_view.size; // Construct new element. - AllocatorTraits::construct(*GetAllocPtr(), last_ptr, - std::forward<Args>(args)...); + AllocatorTraits<A>::construct(GetAllocator(), last_ptr, + std::forward<Args>(args)...); // Move elements from old backing store to new backing store. ABSL_INTERNAL_TRY { - inlined_vector_internal::ConstructElements( - GetAllocPtr(), allocation_tx.GetData(), &move_values, - storage_view.size); + ConstructElements<A>(GetAllocator(), allocation_tx.GetData(), move_values, + storage_view.size); } ABSL_INTERNAL_CATCH_ANY { - AllocatorTraits::destroy(*GetAllocPtr(), last_ptr); + AllocatorTraits<A>::destroy(GetAllocator(), last_ptr); ABSL_INTERNAL_RETHROW; } // Destroy elements in old backing store. - inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data, - storage_view.size); + DestroyAdapter<A>::DestroyElements(GetAllocator(), storage_view.data, + storage_view.size); DeallocateIfAllocated(); - AcquireAllocatedData(&allocation_tx); + SetAllocation(std::move(allocation_tx).Release()); SetIsAllocated(); AddSize(1); return *last_ptr; } template <typename T, size_t N, typename A> -auto Storage<T, N, A>::Erase(const_iterator from, const_iterator to) - -> iterator { - StorageView storage_view = MakeStorageView(); +auto Storage<T, N, A>::Erase(ConstIterator<A> from, ConstIterator<A> to) + -> Iterator<A> { + StorageView<A> storage_view = MakeStorageView(); - size_type erase_size = std::distance(from, to); - size_type erase_index = - std::distance(const_iterator(storage_view.data), from); - size_type erase_end_index = erase_index + erase_size; + SizeType<A> erase_size = std::distance(from, to); + SizeType<A> erase_index = + std::distance(ConstIterator<A>(storage_view.data), from); + SizeType<A> erase_end_index = erase_index + erase_size; - IteratorValueAdapter<MoveIterator> move_values( - MoveIterator(storage_view.data + erase_end_index)); + IteratorValueAdapter<A, MoveIterator<A>> move_values( + MoveIterator<A>(storage_view.data + erase_end_index)); - inlined_vector_internal::AssignElements(storage_view.data + erase_index, - &move_values, - storage_view.size - erase_end_index); + AssignElements<A>(storage_view.data + erase_index, move_values, + storage_view.size - erase_end_index); - inlined_vector_internal::DestroyElements( - GetAllocPtr(), storage_view.data + (storage_view.size - erase_size), + DestroyAdapter<A>::DestroyElements( + GetAllocator(), storage_view.data + (storage_view.size - erase_size), erase_size); SubtractSize(erase_size); - return iterator(storage_view.data + erase_index); + return Iterator<A>(storage_view.data + erase_index); } template <typename T, size_t N, typename A> -auto Storage<T, N, A>::Reserve(size_type requested_capacity) -> void { - StorageView storage_view = MakeStorageView(); +auto Storage<T, N, A>::Reserve(SizeType<A> requested_capacity) -> void { + StorageView<A> storage_view = MakeStorageView(); if (ABSL_PREDICT_FALSE(requested_capacity <= storage_view.capacity)) return; - AllocationTransaction allocation_tx(GetAllocPtr()); + AllocationTransaction<A> allocation_tx(GetAllocator()); - IteratorValueAdapter<MoveIterator> move_values( - MoveIterator(storage_view.data)); + IteratorValueAdapter<A, MoveIterator<A>> move_values( + MoveIterator<A>(storage_view.data)); - size_type new_capacity = + SizeType<A> new_requested_capacity = ComputeCapacity(storage_view.capacity, requested_capacity); - pointer new_data = allocation_tx.Allocate(new_capacity); + Pointer<A> new_data = allocation_tx.Allocate(new_requested_capacity); - inlined_vector_internal::ConstructElements(GetAllocPtr(), new_data, - &move_values, storage_view.size); + ConstructElements<A>(GetAllocator(), new_data, move_values, + storage_view.size); - inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data, - storage_view.size); + DestroyAdapter<A>::DestroyElements(GetAllocator(), storage_view.data, + storage_view.size); DeallocateIfAllocated(); - AcquireAllocatedData(&allocation_tx); + SetAllocation(std::move(allocation_tx).Release()); SetIsAllocated(); } template <typename T, size_t N, typename A> auto Storage<T, N, A>::ShrinkToFit() -> void { // May only be called on allocated instances! - assert(GetIsAllocated()); + ABSL_HARDENING_ASSERT(GetIsAllocated()); - StorageView storage_view{GetAllocatedData(), GetSize(), - GetAllocatedCapacity()}; + StorageView<A> storage_view{GetAllocatedData(), GetSize(), + GetAllocatedCapacity()}; if (ABSL_PREDICT_FALSE(storage_view.size == storage_view.capacity)) return; - AllocationTransaction allocation_tx(GetAllocPtr()); + AllocationTransaction<A> allocation_tx(GetAllocator()); - IteratorValueAdapter<MoveIterator> move_values( - MoveIterator(storage_view.data)); + IteratorValueAdapter<A, MoveIterator<A>> move_values( + MoveIterator<A>(storage_view.data)); - pointer construct_data; + Pointer<A> construct_data; if (storage_view.size > GetInlinedCapacity()) { - size_type new_capacity = storage_view.size; - construct_data = allocation_tx.Allocate(new_capacity); + SizeType<A> requested_capacity = storage_view.size; + construct_data = allocation_tx.Allocate(requested_capacity); + if (allocation_tx.GetCapacity() >= storage_view.capacity) { + // Already using the smallest available heap allocation. + return; + } } else { construct_data = GetInlinedData(); } ABSL_INTERNAL_TRY { - inlined_vector_internal::ConstructElements(GetAllocPtr(), construct_data, - &move_values, storage_view.size); + ConstructElements<A>(GetAllocator(), construct_data, move_values, + storage_view.size); } ABSL_INTERNAL_CATCH_ANY { - SetAllocatedData(storage_view.data, storage_view.capacity); + SetAllocation({storage_view.data, storage_view.capacity}); ABSL_INTERNAL_RETHROW; } - inlined_vector_internal::DestroyElements(GetAllocPtr(), storage_view.data, - storage_view.size); + DestroyAdapter<A>::DestroyElements(GetAllocator(), storage_view.data, + storage_view.size); - AllocatorTraits::deallocate(*GetAllocPtr(), storage_view.data, - storage_view.capacity); + MallocAdapter<A>::Deallocate(GetAllocator(), storage_view.data, + storage_view.capacity); if (allocation_tx.DidAllocate()) { - AcquireAllocatedData(&allocation_tx); + SetAllocation(std::move(allocation_tx).Release()); } else { UnsetIsAllocated(); } @@ -895,7 +881,7 @@ auto Storage<T, N, A>::ShrinkToFit() -> void { template <typename T, size_t N, typename A> auto Storage<T, N, A>::Swap(Storage* other_storage_ptr) -> void { using std::swap; - assert(this != other_storage_ptr); + ABSL_HARDENING_ASSERT(this != other_storage_ptr); if (GetIsAllocated() && other_storage_ptr->GetIsAllocated()) { swap(data_.allocated, other_storage_ptr->data_.allocated); @@ -904,20 +890,20 @@ auto Storage<T, N, A>::Swap(Storage* other_storage_ptr) -> void { Storage* large_ptr = other_storage_ptr; if (small_ptr->GetSize() > large_ptr->GetSize()) swap(small_ptr, large_ptr); - for (size_type i = 0; i < small_ptr->GetSize(); ++i) { + for (SizeType<A> i = 0; i < small_ptr->GetSize(); ++i) { swap(small_ptr->GetInlinedData()[i], large_ptr->GetInlinedData()[i]); } - IteratorValueAdapter<MoveIterator> move_values( - MoveIterator(large_ptr->GetInlinedData() + small_ptr->GetSize())); + IteratorValueAdapter<A, MoveIterator<A>> move_values( + MoveIterator<A>(large_ptr->GetInlinedData() + small_ptr->GetSize())); - inlined_vector_internal::ConstructElements( - large_ptr->GetAllocPtr(), - small_ptr->GetInlinedData() + small_ptr->GetSize(), &move_values, - large_ptr->GetSize() - small_ptr->GetSize()); + ConstructElements<A>(large_ptr->GetAllocator(), + small_ptr->GetInlinedData() + small_ptr->GetSize(), + move_values, + large_ptr->GetSize() - small_ptr->GetSize()); - inlined_vector_internal::DestroyElements( - large_ptr->GetAllocPtr(), + DestroyAdapter<A>::DestroyElements( + large_ptr->GetAllocator(), large_ptr->GetInlinedData() + small_ptr->GetSize(), large_ptr->GetSize() - small_ptr->GetSize()); } else { @@ -925,37 +911,37 @@ auto Storage<T, N, A>::Swap(Storage* other_storage_ptr) -> void { Storage* inlined_ptr = other_storage_ptr; if (!allocated_ptr->GetIsAllocated()) swap(allocated_ptr, inlined_ptr); - StorageView allocated_storage_view{allocated_ptr->GetAllocatedData(), - allocated_ptr->GetSize(), - allocated_ptr->GetAllocatedCapacity()}; + StorageView<A> allocated_storage_view{ + allocated_ptr->GetAllocatedData(), allocated_ptr->GetSize(), + allocated_ptr->GetAllocatedCapacity()}; - IteratorValueAdapter<MoveIterator> move_values( - MoveIterator(inlined_ptr->GetInlinedData())); + IteratorValueAdapter<A, MoveIterator<A>> move_values( + MoveIterator<A>(inlined_ptr->GetInlinedData())); ABSL_INTERNAL_TRY { - inlined_vector_internal::ConstructElements( - inlined_ptr->GetAllocPtr(), allocated_ptr->GetInlinedData(), - &move_values, inlined_ptr->GetSize()); + ConstructElements<A>(inlined_ptr->GetAllocator(), + allocated_ptr->GetInlinedData(), move_values, + inlined_ptr->GetSize()); } ABSL_INTERNAL_CATCH_ANY { - allocated_ptr->SetAllocatedData(allocated_storage_view.data, - allocated_storage_view.capacity); + allocated_ptr->SetAllocation(Allocation<A>{ + allocated_storage_view.data, allocated_storage_view.capacity}); ABSL_INTERNAL_RETHROW; } - inlined_vector_internal::DestroyElements(inlined_ptr->GetAllocPtr(), - inlined_ptr->GetInlinedData(), - inlined_ptr->GetSize()); + DestroyAdapter<A>::DestroyElements(inlined_ptr->GetAllocator(), + inlined_ptr->GetInlinedData(), + inlined_ptr->GetSize()); - inlined_ptr->SetAllocatedData(allocated_storage_view.data, - allocated_storage_view.capacity); + inlined_ptr->SetAllocation(Allocation<A>{allocated_storage_view.data, + allocated_storage_view.capacity}); } swap(GetSizeAndIsAllocated(), other_storage_ptr->GetSizeAndIsAllocated()); - swap(*GetAllocPtr(), *other_storage_ptr->GetAllocPtr()); + swap(GetAllocator(), other_storage_ptr->GetAllocator()); } -// End ignore "maybe-uninitialized" +// End ignore "array-bounds" #if !defined(__clang__) && defined(__GNUC__) #pragma GCC diagnostic pop #endif diff --git a/absl/container/internal/layout_test.cc b/absl/container/internal/layout_test.cc index 1d7158ff..54e5d5bb 100644 --- a/absl/container/internal/layout_test.cc +++ b/absl/container/internal/layout_test.cc @@ -1350,7 +1350,13 @@ TEST(Layout, CustomAlignment) { TEST(Layout, OverAligned) { constexpr size_t M = alignof(max_align_t); constexpr Layout<unsigned char, Aligned<unsigned char, 2 * M>> x(1, 3); +#ifdef __GNUC__ + // Using __attribute__ ((aligned ())) instead of alignas to bypass a gcc bug: + // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89357 + __attribute__((aligned(2 * M))) unsigned char p[x.AllocSize()]; +#else alignas(2 * M) unsigned char p[x.AllocSize()]; +#endif EXPECT_EQ(2 * M + 3, x.AllocSize()); EXPECT_THAT(x.Pointers(p), Tuple(p + 0, p + 2 * M)); } diff --git a/absl/container/internal/node_hash_policy.h b/absl/container/internal/node_slot_policy.h index 4617162f..baba5743 100644 --- a/absl/container/internal/node_hash_policy.h +++ b/absl/container/internal/node_slot_policy.h @@ -30,8 +30,8 @@ // It may also optionally define `value()` and `apply()`. For documentation on // these, see hash_policy_traits.h. -#ifndef ABSL_CONTAINER_INTERNAL_NODE_HASH_POLICY_H_ -#define ABSL_CONTAINER_INTERNAL_NODE_HASH_POLICY_H_ +#ifndef ABSL_CONTAINER_INTERNAL_NODE_SLOT_POLICY_H_ +#define ABSL_CONTAINER_INTERNAL_NODE_SLOT_POLICY_H_ #include <cassert> #include <cstddef> @@ -46,7 +46,7 @@ ABSL_NAMESPACE_BEGIN namespace container_internal { template <class Reference, class Policy> -struct node_hash_policy { +struct node_slot_policy { static_assert(std::is_lvalue_reference<Reference>::value, ""); using slot_type = typename std::remove_cv< @@ -89,4 +89,4 @@ struct node_hash_policy { ABSL_NAMESPACE_END } // namespace absl -#endif // ABSL_CONTAINER_INTERNAL_NODE_HASH_POLICY_H_ +#endif // ABSL_CONTAINER_INTERNAL_NODE_SLOT_POLICY_H_ diff --git a/absl/container/internal/node_hash_policy_test.cc b/absl/container/internal/node_slot_policy_test.cc index 84aabba9..51b7467b 100644 --- a/absl/container/internal/node_hash_policy_test.cc +++ b/absl/container/internal/node_slot_policy_test.cc @@ -12,7 +12,7 @@ // See the License for the specific language governing permissions and // limitations under the License. -#include "absl/container/internal/node_hash_policy.h" +#include "absl/container/internal/node_slot_policy.h" #include <memory> @@ -27,7 +27,7 @@ namespace { using ::testing::Pointee; -struct Policy : node_hash_policy<int&, Policy> { +struct Policy : node_slot_policy<int&, Policy> { using key_type = int; using init_type = int; diff --git a/absl/container/internal/raw_hash_map.h b/absl/container/internal/raw_hash_map.h index 0a02757d..c7df2efc 100644 --- a/absl/container/internal/raw_hash_map.h +++ b/absl/container/internal/raw_hash_map.h @@ -51,8 +51,9 @@ class raw_hash_map : public raw_hash_set<Policy, Hash, Eq, Alloc> { using key_arg = typename KeyArgImpl::template type<K, key_type>; static_assert(!std::is_reference<key_type>::value, ""); - // TODO(alkis): remove this assertion and verify that reference mapped_type is - // supported. + + // TODO(b/187807849): Evaluate whether to support reference mapped_type and + // remove this assertion if/when it is supported. static_assert(!std::is_reference<mapped_type>::value, ""); using iterator = typename raw_hash_map::raw_hash_set::iterator; diff --git a/absl/container/internal/raw_hash_set.cc b/absl/container/internal/raw_hash_set.cc index bfef071f..c63a2e02 100644 --- a/absl/container/internal/raw_hash_set.cc +++ b/absl/container/internal/raw_hash_set.cc @@ -23,7 +23,17 @@ namespace absl { ABSL_NAMESPACE_BEGIN namespace container_internal { +// A single block of empty control bytes for tables without any slots allocated. +// This enables removing a branch in the hot path of find(). +alignas(16) ABSL_CONST_INIT ABSL_DLL const ctrl_t kEmptyGroup[16] = { + ctrl_t::kSentinel, ctrl_t::kEmpty, ctrl_t::kEmpty, ctrl_t::kEmpty, + ctrl_t::kEmpty, ctrl_t::kEmpty, ctrl_t::kEmpty, ctrl_t::kEmpty, + ctrl_t::kEmpty, ctrl_t::kEmpty, ctrl_t::kEmpty, ctrl_t::kEmpty, + ctrl_t::kEmpty, ctrl_t::kEmpty, ctrl_t::kEmpty, ctrl_t::kEmpty}; + +#ifdef ABSL_INTERNAL_NEED_REDUNDANT_CONSTEXPR_DECL constexpr size_t Group::kWidth; +#endif // Returns "random" seed. inline size_t RandomSeed() { @@ -37,24 +47,24 @@ inline size_t RandomSeed() { return value ^ static_cast<size_t>(reinterpret_cast<uintptr_t>(&counter)); } -bool ShouldInsertBackwards(size_t hash, ctrl_t* ctrl) { +bool ShouldInsertBackwards(size_t hash, const ctrl_t* ctrl) { // To avoid problems with weak hashes and single bit tests, we use % 13. // TODO(kfm,sbenza): revisit after we do unconditional mixing return (H1(hash, ctrl) ^ RandomSeed()) % 13 > 6; } -void ConvertDeletedToEmptyAndFullToDeleted( - ctrl_t* ctrl, size_t capacity) { - assert(ctrl[capacity] == kSentinel); +void ConvertDeletedToEmptyAndFullToDeleted(ctrl_t* ctrl, size_t capacity) { + assert(ctrl[capacity] == ctrl_t::kSentinel); assert(IsValidCapacity(capacity)); - for (ctrl_t* pos = ctrl; pos != ctrl + capacity + 1; pos += Group::kWidth) { + for (ctrl_t* pos = ctrl; pos < ctrl + capacity; pos += Group::kWidth) { Group{pos}.ConvertSpecialToEmptyAndFullToDeleted(pos); } // Copy the cloned ctrl bytes. - std::memcpy(ctrl + capacity + 1, ctrl, Group::kWidth); - ctrl[capacity] = kSentinel; + std::memcpy(ctrl + capacity + 1, ctrl, NumClonedBytes()); + ctrl[capacity] = ctrl_t::kSentinel; } - +// Extern template instantiotion for inline function. +template FindInfo find_first_non_full(const ctrl_t*, size_t, size_t); } // namespace container_internal ABSL_NAMESPACE_END diff --git a/absl/container/internal/raw_hash_set.h b/absl/container/internal/raw_hash_set.h index 8615de8b..ea912f83 100644 --- a/absl/container/internal/raw_hash_set.h +++ b/absl/container/internal/raw_hash_set.h @@ -53,40 +53,121 @@ // // IMPLEMENTATION DETAILS // -// The table stores elements inline in a slot array. In addition to the slot -// array the table maintains some control state per slot. The extra state is one -// byte per slot and stores empty or deleted marks, or alternatively 7 bits from -// the hash of an occupied slot. The table is split into logical groups of -// slots, like so: +// # Table Layout +// +// A raw_hash_set's backing array consists of control bytes followed by slots +// that may or may not contain objects. +// +// The layout of the backing array, for `capacity` slots, is thus, as a +// pseudo-struct: +// +// struct BackingArray { +// // Control bytes for the "real" slots. +// ctrl_t ctrl[capacity]; +// // Always `ctrl_t::kSentinel`. This is used by iterators to find when to +// // stop and serves no other purpose. +// ctrl_t sentinel; +// // A copy of the first `kWidth - 1` elements of `ctrl`. This is used so +// // that if a probe sequence picks a value near the end of `ctrl`, +// // `Group` will have valid control bytes to look at. +// ctrl_t clones[kWidth - 1]; +// // The actual slot data. +// slot_type slots[capacity]; +// }; +// +// The length of this array is computed by `AllocSize()` below. +// +// Control bytes (`ctrl_t`) are bytes (collected into groups of a +// platform-specific size) that define the state of the corresponding slot in +// the slot array. Group manipulation is tightly optimized to be as efficient +// as possible: SSE and friends on x86, clever bit operations on other arches. // // Group 1 Group 2 Group 3 // +---------------+---------------+---------------+ // | | | | | | | | | | | | | | | | | | | | | | | | | // +---------------+---------------+---------------+ // -// On lookup the hash is split into two parts: -// - H2: 7 bits (those stored in the control bytes) -// - H1: the rest of the bits -// The groups are probed using H1. For each group the slots are matched to H2 in -// parallel. Because H2 is 7 bits (128 states) and the number of slots per group -// is low (8 or 16) in almost all cases a match in H2 is also a lookup hit. +// Each control byte is either a special value for empty slots, deleted slots +// (sometimes called *tombstones*), and a special end-of-table marker used by +// iterators, or, if occupied, seven bits (H2) from the hash of the value in the +// corresponding slot. +// +// Storing control bytes in a separate array also has beneficial cache effects, +// since more logical slots will fit into a cache line. +// +// # Hashing +// +// We compute two separate hashes, `H1` and `H2`, from the hash of an object. +// `H1(hash(x))` is an index into `slots`, and essentially the starting point +// for the probe sequence. `H2(hash(x))` is a 7-bit value used to filter out +// objects that cannot possibly be the one we are looking for. +// +// # Table operations. +// +// The key operations are `insert`, `find`, and `erase`. +// +// Since `insert` and `erase` are implemented in terms of `find`, we describe +// `find` first. To `find` a value `x`, we compute `hash(x)`. From +// `H1(hash(x))` and the capacity, we construct a `probe_seq` that visits every +// group of slots in some interesting order. // -// On insert, once the right group is found (as in lookup), its slots are -// filled in order. +// We now walk through these indices. At each index, we select the entire group +// starting with that index and extract potential candidates: occupied slots +// with a control byte equal to `H2(hash(x))`. If we find an empty slot in the +// group, we stop and return an error. Each candidate slot `y` is compared with +// `x`; if `x == y`, we are done and return `&y`; otherwise we contine to the +// next probe index. Tombstones effectively behave like full slots that never +// match the value we're looking for. // -// On erase a slot is cleared. In case the group did not have any empty slots -// before the erase, the erased slot is marked as deleted. +// The `H2` bits ensure when we compare a slot to an object with `==`, we are +// likely to have actually found the object. That is, the chance is low that +// `==` is called and returns `false`. Thus, when we search for an object, we +// are unlikely to call `==` many times. This likelyhood can be analyzed as +// follows (assuming that H2 is a random enough hash function). // -// Groups without empty slots (but maybe with deleted slots) extend the probe -// sequence. The probing algorithm is quadratic. Given N the number of groups, -// the probing function for the i'th probe is: +// Let's assume that there are `k` "wrong" objects that must be examined in a +// probe sequence. For example, when doing a `find` on an object that is in the +// table, `k` is the number of objects between the start of the probe sequence +// and the final found object (not including the final found object). The +// expected number of objects with an H2 match is then `k/128`. Measurements +// and analysis indicate that even at high load factors, `k` is less than 32, +// meaning that the number of "false positive" comparisons we must perform is +// less than 1/8 per `find`. + +// `insert` is implemented in terms of `unchecked_insert`, which inserts a +// value presumed to not be in the table (violating this requirement will cause +// the table to behave erratically). Given `x` and its hash `hash(x)`, to insert +// it, we construct a `probe_seq` once again, and use it to find the first +// group with an unoccupied (empty *or* deleted) slot. We place `x` into the +// first such slot in the group and mark it as full with `x`'s H2. // -// P(0) = H1 % N +// To `insert`, we compose `unchecked_insert` with `find`. We compute `h(x)` and +// perform a `find` to see if it's already present; if it is, we're done. If +// it's not, we may decide the table is getting overcrowded (i.e. the load +// factor is greater than 7/8 for big tables; `is_small()` tables use a max load +// factor of 1); in this case, we allocate a bigger array, `unchecked_insert` +// each element of the table into the new array (we know that no insertion here +// will insert an already-present value), and discard the old backing array. At +// this point, we may `unchecked_insert` the value `x`. // -// P(i) = (P(i - 1) + i) % N +// Below, `unchecked_insert` is partly implemented by `prepare_insert`, which +// presents a viable, initialized slot pointee to the caller. // -// This probing function guarantees that after N probes, all the groups of the -// table will be probed exactly once. +// `erase` is implemented in terms of `erase_at`, which takes an index to a +// slot. Given an offset, we simply create a tombstone and destroy its contents. +// If we can prove that the slot would not appear in a probe sequence, we can +// make the slot as empty, instead. We can prove this by observing that if a +// group has any empty slots, it has never been full (assuming we never create +// an empty slot in a group with no empties, which this heuristic guarantees we +// never do) and find would stop at this group anyways (since it does not probe +// beyond groups with empties). +// +// `erase` is `erase_at` composed with `find`: if we +// have a value `x`, we can perform a `find`, and then `erase_at` the resulting +// slot. +// +// To iterate, we simply traverse the array, skipping empty and deleted slots +// and stopping when we hit a `kSentinel`. #ifndef ABSL_CONTAINER_INTERNAL_RAW_HASH_SET_H_ #define ABSL_CONTAINER_INTERNAL_RAW_HASH_SET_H_ @@ -102,7 +183,9 @@ #include <type_traits> #include <utility> +#include "absl/base/config.h" #include "absl/base/internal/endian.h" +#include "absl/base/internal/prefetch.h" #include "absl/base/optimization.h" #include "absl/base/port.h" #include "absl/container/internal/common.h" @@ -111,13 +194,27 @@ #include "absl/container/internal/hash_policy_traits.h" #include "absl/container/internal/hashtable_debug_hooks.h" #include "absl/container/internal/hashtablez_sampler.h" -#include "absl/container/internal/have_sse.h" -#include "absl/container/internal/layout.h" #include "absl/memory/memory.h" #include "absl/meta/type_traits.h" #include "absl/numeric/bits.h" #include "absl/utility/utility.h" +#ifdef ABSL_INTERNAL_HAVE_SSE2 +#include <emmintrin.h> +#endif + +#ifdef ABSL_INTERNAL_HAVE_SSSE3 +#include <tmmintrin.h> +#endif + +#ifdef _MSC_VER +#include <intrin.h> +#endif + +#ifdef ABSL_INTERNAL_HAVE_ARM_NEON +#include <arm_neon.h> +#endif + namespace absl { ABSL_NAMESPACE_BEGIN namespace container_internal { @@ -132,14 +229,40 @@ template <typename AllocType> void SwapAlloc(AllocType& /*lhs*/, AllocType& /*rhs*/, std::false_type /* propagate_on_container_swap */) {} +// The state for a probe sequence. +// +// Currently, the sequence is a triangular progression of the form +// +// p(i) := Width * (i^2 + i)/2 + hash (mod mask + 1) +// +// The use of `Width` ensures that each probe step does not overlap groups; +// the sequence effectively outputs the addresses of *groups* (although not +// necessarily aligned to any boundary). The `Group` machinery allows us +// to check an entire group with minimal branching. +// +// Wrapping around at `mask + 1` is important, but not for the obvious reason. +// As described above, the first few entries of the control byte array +// are mirrored at the end of the array, which `Group` will find and use +// for selecting candidates. However, when those candidates' slots are +// actually inspected, there are no corresponding slots for the cloned bytes, +// so we need to make sure we've treated those offsets as "wrapping around". +// +// It turns out that this probe sequence visits every group exactly once if the +// number of groups is a power of two, since (i^2+i)/2 is a bijection in +// Z/(2^m). See https://en.wikipedia.org/wiki/Quadratic_probing template <size_t Width> class probe_seq { public: + // Creates a new probe sequence using `hash` as the initial value of the + // sequence and `mask` (usually the capacity of the table) as the mask to + // apply to each value in the progression. probe_seq(size_t hash, size_t mask) { assert(((mask + 1) & mask) == 0 && "not a mask"); mask_ = mask; offset_ = hash & mask_; } + + // The offset within the table, i.e., the value `p(i)` above. size_t offset() const { return offset_; } size_t offset(size_t i) const { return (offset_ + i) & mask_; } @@ -148,7 +271,7 @@ class probe_seq { offset_ += index_; offset_ &= mask_; } - // 0-based probe index. The i-th probe in the probe sequence. + // 0-based probe index, a multiple of `Width`. size_t index() const { return index_; } private: @@ -172,9 +295,9 @@ struct IsDecomposable : std::false_type {}; template <class Policy, class Hash, class Eq, class... Ts> struct IsDecomposable< - absl::void_t<decltype( - Policy::apply(RequireUsableKey<typename Policy::key_type, Hash, Eq>(), - std::declval<Ts>()...))>, + absl::void_t<decltype(Policy::apply( + RequireUsableKey<typename Policy::key_type, Hash, Eq>(), + std::declval<Ts>()...))>, Policy, Hash, Eq, Ts...> : std::true_type {}; // TODO(alkis): Switch to std::is_nothrow_swappable when gcc/clang supports it. @@ -190,57 +313,84 @@ constexpr bool IsNoThrowSwappable(std::false_type /* is_swappable */) { template <typename T> uint32_t TrailingZeros(T x) { - ABSL_INTERNAL_ASSUME(x != 0); - return countr_zero(x); + ABSL_ASSUME(x != 0); + return static_cast<uint32_t>(countr_zero(x)); } -// An abstraction over a bitmask. It provides an easy way to iterate through the -// indexes of the set bits of a bitmask. When Shift=0 (platforms with SSE), -// this is a true bitmask. On non-SSE, platforms the arithematic used to -// emulate the SSE behavior works in bytes (Shift=3) and leaves each bytes as -// either 0x00 or 0x80. +// An abstract bitmask, such as that emitted by a SIMD instruction. // -// For example: -// for (int i : BitMask<uint32_t, 16>(0x5)) -> yields 0, 2 -// for (int i : BitMask<uint64_t, 8, 3>(0x0000000080800000)) -> yields 2, 3 +// Specifically, this type implements a simple bitset whose representation is +// controlled by `SignificantBits` and `Shift`. `SignificantBits` is the number +// of abstract bits in the bitset, while `Shift` is the log-base-two of the +// width of an abstract bit in the representation. +// This mask provides operations for any number of real bits set in an abstract +// bit. To add iteration on top of that, implementation must guarantee no more +// than one real bit is set in an abstract bit. template <class T, int SignificantBits, int Shift = 0> -class BitMask { - static_assert(std::is_unsigned<T>::value, ""); - static_assert(Shift == 0 || Shift == 3, ""); - +class NonIterableBitMask { public: - // These are useful for unit tests (gunit). - using value_type = int; - using iterator = BitMask; - using const_iterator = BitMask; + explicit NonIterableBitMask(T mask) : mask_(mask) {} - explicit BitMask(T mask) : mask_(mask) {} - BitMask& operator++() { - mask_ &= (mask_ - 1); - return *this; - } - explicit operator bool() const { return mask_ != 0; } - int operator*() const { return LowestBitSet(); } + explicit operator bool() const { return this->mask_ != 0; } + + // Returns the index of the lowest *abstract* bit set in `self`. uint32_t LowestBitSet() const { return container_internal::TrailingZeros(mask_) >> Shift; } + + // Returns the index of the highest *abstract* bit set in `self`. uint32_t HighestBitSet() const { return static_cast<uint32_t>((bit_width(mask_) - 1) >> Shift); } - BitMask begin() const { return *this; } - BitMask end() const { return BitMask(0); } - + // Return the number of trailing zero *abstract* bits. uint32_t TrailingZeros() const { return container_internal::TrailingZeros(mask_) >> Shift; } + // Return the number of leading zero *abstract* bits. uint32_t LeadingZeros() const { constexpr int total_significant_bits = SignificantBits << Shift; constexpr int extra_bits = sizeof(T) * 8 - total_significant_bits; - return countl_zero(mask_ << extra_bits) >> Shift; + return static_cast<uint32_t>(countl_zero(mask_ << extra_bits)) >> Shift; } + T mask_; +}; + +// Mask that can be iterable +// +// For example, when `SignificantBits` is 16 and `Shift` is zero, this is just +// an ordinary 16-bit bitset occupying the low 16 bits of `mask`. When +// `SignificantBits` is 8 and `Shift` is 3, abstract bits are represented as +// the bytes `0x00` and `0x80`, and it occupies all 64 bits of the bitmask. +// +// For example: +// for (int i : BitMask<uint32_t, 16>(0b101)) -> yields 0, 2 +// for (int i : BitMask<uint64_t, 8, 3>(0x0000000080800000)) -> yields 2, 3 +template <class T, int SignificantBits, int Shift = 0> +class BitMask : public NonIterableBitMask<T, SignificantBits, Shift> { + using Base = NonIterableBitMask<T, SignificantBits, Shift>; + static_assert(std::is_unsigned<T>::value, ""); + static_assert(Shift == 0 || Shift == 3, ""); + + public: + explicit BitMask(T mask) : Base(mask) {} + // BitMask is an iterator over the indices of its abstract bits. + using value_type = int; + using iterator = BitMask; + using const_iterator = BitMask; + + BitMask& operator++() { + this->mask_ &= (this->mask_ - 1); + return *this; + } + + uint32_t operator*() const { return Base::LowestBitSet(); } + + BitMask begin() const { return *this; } + BitMask end() const { return BitMask(0); } + private: friend bool operator==(const BitMask& a, const BitMask& b) { return a.mask_ == b.mask_; @@ -248,75 +398,127 @@ class BitMask { friend bool operator!=(const BitMask& a, const BitMask& b) { return a.mask_ != b.mask_; } - - T mask_; }; -using ctrl_t = signed char; using h2_t = uint8_t; // The values here are selected for maximum performance. See the static asserts // below for details. -enum Ctrl : ctrl_t { + +// A `ctrl_t` is a single control byte, which can have one of four +// states: empty, deleted, full (which has an associated seven-bit h2_t value) +// and the sentinel. They have the following bit patterns: +// +// empty: 1 0 0 0 0 0 0 0 +// deleted: 1 1 1 1 1 1 1 0 +// full: 0 h h h h h h h // h represents the hash bits. +// sentinel: 1 1 1 1 1 1 1 1 +// +// These values are specifically tuned for SSE-flavored SIMD. +// The static_asserts below detail the source of these choices. +// +// We use an enum class so that when strict aliasing is enabled, the compiler +// knows ctrl_t doesn't alias other types. +enum class ctrl_t : int8_t { kEmpty = -128, // 0b10000000 kDeleted = -2, // 0b11111110 kSentinel = -1, // 0b11111111 }; static_assert( - kEmpty & kDeleted & kSentinel & 0x80, + (static_cast<int8_t>(ctrl_t::kEmpty) & + static_cast<int8_t>(ctrl_t::kDeleted) & + static_cast<int8_t>(ctrl_t::kSentinel) & 0x80) != 0, "Special markers need to have the MSB to make checking for them efficient"); -static_assert(kEmpty < kSentinel && kDeleted < kSentinel, - "kEmpty and kDeleted must be smaller than kSentinel to make the " - "SIMD test of IsEmptyOrDeleted() efficient"); -static_assert(kSentinel == -1, - "kSentinel must be -1 to elide loading it from memory into SIMD " - "registers (pcmpeqd xmm, xmm)"); -static_assert(kEmpty == -128, - "kEmpty must be -128 to make the SIMD check for its " +static_assert( + ctrl_t::kEmpty < ctrl_t::kSentinel && ctrl_t::kDeleted < ctrl_t::kSentinel, + "ctrl_t::kEmpty and ctrl_t::kDeleted must be smaller than " + "ctrl_t::kSentinel to make the SIMD test of IsEmptyOrDeleted() efficient"); +static_assert( + ctrl_t::kSentinel == static_cast<ctrl_t>(-1), + "ctrl_t::kSentinel must be -1 to elide loading it from memory into SIMD " + "registers (pcmpeqd xmm, xmm)"); +static_assert(ctrl_t::kEmpty == static_cast<ctrl_t>(-128), + "ctrl_t::kEmpty must be -128 to make the SIMD check for its " "existence efficient (psignb xmm, xmm)"); -static_assert(~kEmpty & ~kDeleted & kSentinel & 0x7F, - "kEmpty and kDeleted must share an unset bit that is not shared " - "by kSentinel to make the scalar test for MatchEmptyOrDeleted() " - "efficient"); -static_assert(kDeleted == -2, - "kDeleted must be -2 to make the implementation of " +static_assert( + (~static_cast<int8_t>(ctrl_t::kEmpty) & + ~static_cast<int8_t>(ctrl_t::kDeleted) & + static_cast<int8_t>(ctrl_t::kSentinel) & 0x7F) != 0, + "ctrl_t::kEmpty and ctrl_t::kDeleted must share an unset bit that is not " + "shared by ctrl_t::kSentinel to make the scalar test for " + "MaskEmptyOrDeleted() efficient"); +static_assert(ctrl_t::kDeleted == static_cast<ctrl_t>(-2), + "ctrl_t::kDeleted must be -2 to make the implementation of " "ConvertSpecialToEmptyAndFullToDeleted efficient"); -// A single block of empty control bytes for tables without any slots allocated. -// This enables removing a branch in the hot path of find(). +ABSL_DLL extern const ctrl_t kEmptyGroup[16]; + +// Returns a pointer to a control byte group that can be used by empty tables. inline ctrl_t* EmptyGroup() { - alignas(16) static constexpr ctrl_t empty_group[] = { - kSentinel, kEmpty, kEmpty, kEmpty, kEmpty, kEmpty, kEmpty, kEmpty, - kEmpty, kEmpty, kEmpty, kEmpty, kEmpty, kEmpty, kEmpty, kEmpty}; - return const_cast<ctrl_t*>(empty_group); + // Const must be cast away here; no uses of this function will actually write + // to it, because it is only used for empty tables. + return const_cast<ctrl_t*>(kEmptyGroup); } // Mixes a randomly generated per-process seed with `hash` and `ctrl` to // randomize insertion order within groups. -bool ShouldInsertBackwards(size_t hash, ctrl_t* ctrl); +bool ShouldInsertBackwards(size_t hash, const ctrl_t* ctrl); -// Returns a hash seed. +// Returns a per-table, hash salt, which changes on resize. This gets mixed into +// H1 to randomize iteration order per-table. // // The seed consists of the ctrl_ pointer, which adds enough entropy to ensure // non-determinism of iteration order in most cases. -inline size_t HashSeed(const ctrl_t* ctrl) { +inline size_t PerTableSalt(const ctrl_t* ctrl) { // The low bits of the pointer have little or no entropy because of // alignment. We shift the pointer to try to use higher entropy bits. A // good number seems to be 12 bits, because that aligns with page size. return reinterpret_cast<uintptr_t>(ctrl) >> 12; } - +// Extracts the H1 portion of a hash: 57 bits mixed with a per-table salt. inline size_t H1(size_t hash, const ctrl_t* ctrl) { - return (hash >> 7) ^ HashSeed(ctrl); + return (hash >> 7) ^ PerTableSalt(ctrl); } -inline ctrl_t H2(size_t hash) { return hash & 0x7F; } -inline bool IsEmpty(ctrl_t c) { return c == kEmpty; } -inline bool IsFull(ctrl_t c) { return c >= 0; } -inline bool IsDeleted(ctrl_t c) { return c == kDeleted; } -inline bool IsEmptyOrDeleted(ctrl_t c) { return c < kSentinel; } +// Extracts the H2 portion of a hash: the 7 bits not used for H1. +// +// These are used as an occupied control byte. +inline h2_t H2(size_t hash) { return hash & 0x7F; } -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 +// Helpers for checking the state of a control byte. +inline bool IsEmpty(ctrl_t c) { return c == ctrl_t::kEmpty; } +inline bool IsFull(ctrl_t c) { return c >= static_cast<ctrl_t>(0); } +inline bool IsDeleted(ctrl_t c) { return c == ctrl_t::kDeleted; } +inline bool IsEmptyOrDeleted(ctrl_t c) { return c < ctrl_t::kSentinel; } + +#ifdef ABSL_INTERNAL_HAVE_SSE2 +// Quick reference guide for intrinsics used below: +// +// * __m128i: An XMM (128-bit) word. +// +// * _mm_setzero_si128: Returns a zero vector. +// * _mm_set1_epi8: Returns a vector with the same i8 in each lane. +// +// * _mm_subs_epi8: Saturating-subtracts two i8 vectors. +// * _mm_and_si128: Ands two i128s together. +// * _mm_or_si128: Ors two i128s together. +// * _mm_andnot_si128: And-nots two i128s together. +// +// * _mm_cmpeq_epi8: Component-wise compares two i8 vectors for equality, +// filling each lane with 0x00 or 0xff. +// * _mm_cmpgt_epi8: Same as above, but using > rather than ==. +// +// * _mm_loadu_si128: Performs an unaligned load of an i128. +// * _mm_storeu_si128: Performs an unaligned store of an i128. +// +// * _mm_sign_epi8: Retains, negates, or zeroes each i8 lane of the first +// argument if the corresponding lane of the second +// argument is positive, negative, or zero, respectively. +// * _mm_movemask_epi8: Selects the sign bit out of each i8 lane and produces a +// bitmask consisting of those bits. +// * _mm_shuffle_epi8: Selects i8s from the first argument, using the low +// four bits of each i8 lane in the second argument as +// indices. // https://github.com/abseil/abseil-cpp/issues/209 // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87853 @@ -345,30 +547,32 @@ struct GroupSse2Impl { BitMask<uint32_t, kWidth> Match(h2_t hash) const { auto match = _mm_set1_epi8(hash); return BitMask<uint32_t, kWidth>( - _mm_movemask_epi8(_mm_cmpeq_epi8(match, ctrl))); + static_cast<uint32_t>(_mm_movemask_epi8(_mm_cmpeq_epi8(match, ctrl)))); } // Returns a bitmask representing the positions of empty slots. - BitMask<uint32_t, kWidth> MatchEmpty() const { -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSSE3 - // This only works because kEmpty is -128. - return BitMask<uint32_t, kWidth>( - _mm_movemask_epi8(_mm_sign_epi8(ctrl, ctrl))); + NonIterableBitMask<uint32_t, kWidth> MaskEmpty() const { +#ifdef ABSL_INTERNAL_HAVE_SSSE3 + // This only works because ctrl_t::kEmpty is -128. + return NonIterableBitMask<uint32_t, kWidth>( + static_cast<uint32_t>(_mm_movemask_epi8(_mm_sign_epi8(ctrl, ctrl)))); #else - return Match(static_cast<h2_t>(kEmpty)); + auto match = _mm_set1_epi8(static_cast<h2_t>(ctrl_t::kEmpty)); + return NonIterableBitMask<uint32_t, kWidth>( + static_cast<uint32_t>(_mm_movemask_epi8(_mm_cmpeq_epi8(match, ctrl)))); #endif } // Returns a bitmask representing the positions of empty or deleted slots. - BitMask<uint32_t, kWidth> MatchEmptyOrDeleted() const { - auto special = _mm_set1_epi8(kSentinel); - return BitMask<uint32_t, kWidth>( - _mm_movemask_epi8(_mm_cmpgt_epi8_fixed(special, ctrl))); + NonIterableBitMask<uint32_t, kWidth> MaskEmptyOrDeleted() const { + auto special = _mm_set1_epi8(static_cast<uint8_t>(ctrl_t::kSentinel)); + return NonIterableBitMask<uint32_t, kWidth>(static_cast<uint32_t>( + _mm_movemask_epi8(_mm_cmpgt_epi8_fixed(special, ctrl)))); } // Returns the number of trailing empty or deleted elements in the group. uint32_t CountLeadingEmptyOrDeleted() const { - auto special = _mm_set1_epi8(kSentinel); + auto special = _mm_set1_epi8(static_cast<uint8_t>(ctrl_t::kSentinel)); return TrailingZeros(static_cast<uint32_t>( _mm_movemask_epi8(_mm_cmpgt_epi8_fixed(special, ctrl)) + 1)); } @@ -376,7 +580,7 @@ struct GroupSse2Impl { void ConvertSpecialToEmptyAndFullToDeleted(ctrl_t* dst) const { auto msbs = _mm_set1_epi8(static_cast<char>(-128)); auto x126 = _mm_set1_epi8(126); -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSSE3 +#ifdef ABSL_INTERNAL_HAVE_SSSE3 auto res = _mm_or_si128(_mm_shuffle_epi8(x126, ctrl), msbs); #else auto zero = _mm_setzero_si128(); @@ -390,6 +594,63 @@ struct GroupSse2Impl { }; #endif // ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 +#if defined(ABSL_INTERNAL_HAVE_ARM_NEON) && defined(ABSL_IS_LITTLE_ENDIAN) +struct GroupAArch64Impl { + static constexpr size_t kWidth = 8; + + explicit GroupAArch64Impl(const ctrl_t* pos) { + ctrl = vld1_u8(reinterpret_cast<const uint8_t*>(pos)); + } + + BitMask<uint64_t, kWidth, 3> Match(h2_t hash) const { + uint8x8_t dup = vdup_n_u8(hash); + auto mask = vceq_u8(ctrl, dup); + constexpr uint64_t msbs = 0x8080808080808080ULL; + return BitMask<uint64_t, kWidth, 3>( + vget_lane_u64(vreinterpret_u64_u8(mask), 0) & msbs); + } + + NonIterableBitMask<uint64_t, kWidth, 3> MaskEmpty() const { + uint64_t mask = + vget_lane_u64(vreinterpret_u64_u8( + vceq_s8(vdup_n_s8(static_cast<h2_t>(ctrl_t::kEmpty)), + vreinterpret_s8_u8(ctrl))), + 0); + return NonIterableBitMask<uint64_t, kWidth, 3>(mask); + } + + NonIterableBitMask<uint64_t, kWidth, 3> MaskEmptyOrDeleted() const { + uint64_t mask = + vget_lane_u64(vreinterpret_u64_u8(vcgt_s8( + vdup_n_s8(static_cast<int8_t>(ctrl_t::kSentinel)), + vreinterpret_s8_u8(ctrl))), + 0); + return NonIterableBitMask<uint64_t, kWidth, 3>(mask); + } + + uint32_t CountLeadingEmptyOrDeleted() const { + uint64_t mask = vget_lane_u64(vreinterpret_u64_u8(ctrl), 0); + // ctrl | ~(ctrl >> 7) will have the lowest bit set to zero for kEmpty and + // kDeleted. We lower all other bits and count number of trailing zeros. + // Clang and GCC optimize countr_zero to rbit+clz without any check for 0, + // so we should be fine. + constexpr uint64_t bits = 0x0101010101010101ULL; + return countr_zero((mask | ~(mask >> 7)) & bits) >> 3; + } + + void ConvertSpecialToEmptyAndFullToDeleted(ctrl_t* dst) const { + uint64_t mask = vget_lane_u64(vreinterpret_u64_u8(ctrl), 0); + constexpr uint64_t msbs = 0x8080808080808080ULL; + constexpr uint64_t lsbs = 0x0101010101010101ULL; + auto x = mask & msbs; + auto res = (~x + (x >> 7)) & ~lsbs; + little_endian::Store64(dst, res); + } + + uint8x8_t ctrl; +}; +#endif // ABSL_INTERNAL_HAVE_ARM_NEON && ABSL_IS_LITTLE_ENDIAN + struct GroupPortableImpl { static constexpr size_t kWidth = 8; @@ -403,7 +664,7 @@ struct GroupPortableImpl { // // Caveat: there are false positives but: // - they only occur if there is a real match - // - they never occur on kEmpty, kDeleted, kSentinel + // - they never occur on ctrl_t::kEmpty, ctrl_t::kDeleted, ctrl_t::kSentinel // - they will be handled gracefully by subsequent checks in code // // Example: @@ -416,19 +677,23 @@ struct GroupPortableImpl { return BitMask<uint64_t, kWidth, 3>((x - lsbs) & ~x & msbs); } - BitMask<uint64_t, kWidth, 3> MatchEmpty() const { + NonIterableBitMask<uint64_t, kWidth, 3> MaskEmpty() const { constexpr uint64_t msbs = 0x8080808080808080ULL; - return BitMask<uint64_t, kWidth, 3>((ctrl & (~ctrl << 6)) & msbs); + return NonIterableBitMask<uint64_t, kWidth, 3>((ctrl & (~ctrl << 6)) & + msbs); } - BitMask<uint64_t, kWidth, 3> MatchEmptyOrDeleted() const { + NonIterableBitMask<uint64_t, kWidth, 3> MaskEmptyOrDeleted() const { constexpr uint64_t msbs = 0x8080808080808080ULL; - return BitMask<uint64_t, kWidth, 3>((ctrl & (~ctrl << 7)) & msbs); + return NonIterableBitMask<uint64_t, kWidth, 3>((ctrl & (~ctrl << 7)) & + msbs); } uint32_t CountLeadingEmptyOrDeleted() const { - constexpr uint64_t gaps = 0x00FEFEFEFEFEFEFEULL; - return (TrailingZeros(((~ctrl & (ctrl >> 7)) | gaps) + 1) + 7) >> 3; + // ctrl | ~(ctrl >> 7) will have the lowest bit set to zero for kEmpty and + // kDeleted. We lower all other bits and count number of trailing zeros. + constexpr uint64_t bits = 0x0101010101010101ULL; + return countr_zero((ctrl | ~(ctrl >> 7)) & bits) >> 3; } void ConvertSpecialToEmptyAndFullToDeleted(ctrl_t* dst) const { @@ -442,28 +707,40 @@ struct GroupPortableImpl { uint64_t ctrl; }; -#if ABSL_INTERNAL_RAW_HASH_SET_HAVE_SSE2 +#ifdef ABSL_INTERNAL_HAVE_SSE2 using Group = GroupSse2Impl; +#elif defined(ABSL_INTERNAL_HAVE_ARM_NEON) && defined(ABSL_IS_LITTLE_ENDIAN) +using Group = GroupAArch64Impl; #else using Group = GroupPortableImpl; #endif +// Returns he number of "cloned control bytes". +// +// This is the number of control bytes that are present both at the beginning +// of the control byte array and at the end, such that we can create a +// `Group::kWidth`-width probe window starting from any control byte. +constexpr size_t NumClonedBytes() { return Group::kWidth - 1; } + template <class Policy, class Hash, class Eq, class Alloc> class raw_hash_set; +// Returns whether `n` is a valid capacity (i.e., number of slots). +// +// A valid capacity is a non-zero integer `2^m - 1`. inline bool IsValidCapacity(size_t n) { return ((n + 1) & n) == 0 && n > 0; } +// Applies the following mapping to every byte in the control array: +// * kDeleted -> kEmpty +// * kEmpty -> kEmpty +// * _ -> kDeleted // PRECONDITION: // IsValidCapacity(capacity) -// ctrl[capacity] == kSentinel -// ctrl[i] != kSentinel for all i < capacity -// Applies mapping for every byte in ctrl: -// DELETED -> EMPTY -// EMPTY -> EMPTY -// FULL -> DELETED +// ctrl[capacity] == ctrl_t::kSentinel +// ctrl[i] != ctrl_t::kSentinel for all i < capacity void ConvertDeletedToEmptyAndFullToDeleted(ctrl_t* ctrl, size_t capacity); -// Rounds up the capacity to the next power of 2 minus 1, with a minimum of 1. +// Converts `n` into the next valid capacity, per `IsValidCapacity`. inline size_t NormalizeCapacity(size_t n) { return n ? ~size_t{} >> countl_zero(n) : 1; } @@ -476,8 +753,8 @@ inline size_t NormalizeCapacity(size_t n) { // never need to probe (the whole table fits in one group) so we don't need a // load factor less than 1. -// Given `capacity` of the table, returns the size (i.e. number of full slots) -// at which we should grow the capacity. +// Given `capacity`, applies the load factor; i.e., it returns the maximum +// number of values we should put into the table before a resizing rehash. inline size_t CapacityToGrowth(size_t capacity) { assert(IsValidCapacity(capacity)); // `capacity*7/8` @@ -487,8 +764,12 @@ inline size_t CapacityToGrowth(size_t capacity) { } return capacity - capacity / 8; } -// From desired "growth" to a lowerbound of the necessary capacity. -// Might not be a valid one and requires NormalizeCapacity(). + +// Given `growth`, "unapplies" the load factor to find how large the capacity +// should be to stay within the load factor. +// +// This might not be a valid capacity and `NormalizeCapacity()` should be +// called on this. inline size_t GrowthToLowerboundCapacity(size_t growth) { // `growth*8/7` if (Group::kWidth == 8 && growth == 7) { @@ -498,16 +779,31 @@ inline size_t GrowthToLowerboundCapacity(size_t growth) { return growth + static_cast<size_t>((static_cast<int64_t>(growth) - 1) / 7); } -inline void AssertIsFull(ctrl_t* ctrl) { - ABSL_HARDENING_ASSERT((ctrl != nullptr && IsFull(*ctrl)) && - "Invalid operation on iterator. The element might have " - "been erased, or the table might have rehashed."); +template <class InputIter> +size_t SelectBucketCountForIterRange(InputIter first, InputIter last, + size_t bucket_count) { + if (bucket_count != 0) { + return bucket_count; + } + using InputIterCategory = + typename std::iterator_traits<InputIter>::iterator_category; + if (std::is_base_of<std::random_access_iterator_tag, + InputIterCategory>::value) { + return GrowthToLowerboundCapacity( + static_cast<size_t>(std::distance(first, last))); + } + return 0; } +#define ABSL_INTERNAL_ASSERT_IS_FULL(ctrl, msg) \ + ABSL_HARDENING_ASSERT((ctrl != nullptr && IsFull(*ctrl)) && msg) + inline void AssertIsValid(ctrl_t* ctrl) { - ABSL_HARDENING_ASSERT((ctrl == nullptr || IsFull(*ctrl)) && - "Invalid operation on iterator. The element might have " - "been erased, or the table might have rehashed."); + ABSL_HARDENING_ASSERT( + (ctrl == nullptr || IsFull(*ctrl)) && + "Invalid operation on iterator. The element might have " + "been erased, the table might have rehashed, or this may " + "be an end() iterator."); } struct FindInfo { @@ -515,42 +811,40 @@ struct FindInfo { size_t probe_length; }; -// The representation of the object has two modes: -// - small: For capacities < kWidth-1 -// - large: For the rest. +// Whether a table is "small". A small table fits entirely into a probing +// group, i.e., has a capacity < `Group::kWidth`. // -// Differences: -// - In small mode we are able to use the whole capacity. The extra control -// bytes give us at least one "empty" control byte to stop the iteration. -// This is important to make 1 a valid capacity. +// In small mode we are able to use the whole capacity. The extra control +// bytes give us at least one "empty" control byte to stop the iteration. +// This is important to make 1 a valid capacity. // -// - In small mode only the first `capacity()` control bytes after the -// sentinel are valid. The rest contain dummy kEmpty values that do not -// represent a real slot. This is important to take into account on -// find_first_non_full(), where we never try ShouldInsertBackwards() for -// small tables. +// In small mode only the first `capacity` control bytes after the sentinel +// are valid. The rest contain dummy ctrl_t::kEmpty values that do not +// represent a real slot. This is important to take into account on +// `find_first_non_full()`, where we never try +// `ShouldInsertBackwards()` for small tables. inline bool is_small(size_t capacity) { return capacity < Group::kWidth - 1; } -inline probe_seq<Group::kWidth> probe(ctrl_t* ctrl, size_t hash, +// Begins a probing operation on `ctrl`, using `hash`. +inline probe_seq<Group::kWidth> probe(const ctrl_t* ctrl, size_t hash, size_t capacity) { return probe_seq<Group::kWidth>(H1(hash, ctrl), capacity); } -// Probes the raw_hash_set with the probe sequence for hash and returns the -// pointer to the first empty or deleted slot. -// NOTE: this function must work with tables having both kEmpty and kDelete -// in one group. Such tables appears during drop_deletes_without_resize. +// Probes an array of control bits using a probe sequence derived from `hash`, +// and returns the offset corresponding to the first deleted or empty slot. +// +// Behavior when the entire table is full is undefined. // -// This function is very useful when insertions happen and: -// - the input is already a set -// - there are enough slots -// - the element with the hash is not in the table -inline FindInfo find_first_non_full(ctrl_t* ctrl, size_t hash, +// NOTE: this function must work with tables having both empty and deleted +// slots in the same group. Such tables appear during `erase()`. +template <typename = void> +inline FindInfo find_first_non_full(const ctrl_t* ctrl, size_t hash, size_t capacity) { auto seq = probe(ctrl, hash, capacity); while (true) { Group g{ctrl + seq.offset()}; - auto mask = g.MatchEmptyOrDeleted(); + auto mask = g.MaskEmptyOrDeleted(); if (mask) { #if !defined(NDEBUG) // We want to add entropy even when ASLR is not enabled. @@ -564,10 +858,66 @@ inline FindInfo find_first_non_full(ctrl_t* ctrl, size_t hash, return {seq.offset(mask.LowestBitSet()), seq.index()}; } seq.next(); - assert(seq.index() < capacity && "full table!"); + assert(seq.index() <= capacity && "full table!"); + } +} + +// Extern template for inline function keep possibility of inlining. +// When compiler decided to not inline, no symbols will be added to the +// corresponding translation unit. +extern template FindInfo find_first_non_full(const ctrl_t*, size_t, size_t); + +// Sets `ctrl` to `{kEmpty, kSentinel, ..., kEmpty}`, marking the entire +// array as marked as empty. +inline void ResetCtrl(size_t capacity, ctrl_t* ctrl, const void* slot, + size_t slot_size) { + std::memset(ctrl, static_cast<int8_t>(ctrl_t::kEmpty), + capacity + 1 + NumClonedBytes()); + ctrl[capacity] = ctrl_t::kSentinel; + SanitizerPoisonMemoryRegion(slot, slot_size * capacity); +} + +// Sets `ctrl[i]` to `h`. +// +// Unlike setting it directly, this function will perform bounds checks and +// mirror the value to the cloned tail if necessary. +inline void SetCtrl(size_t i, ctrl_t h, size_t capacity, ctrl_t* ctrl, + const void* slot, size_t slot_size) { + assert(i < capacity); + + auto* slot_i = static_cast<const char*>(slot) + i * slot_size; + if (IsFull(h)) { + SanitizerUnpoisonMemoryRegion(slot_i, slot_size); + } else { + SanitizerPoisonMemoryRegion(slot_i, slot_size); } + + ctrl[i] = h; + ctrl[((i - NumClonedBytes()) & capacity) + (NumClonedBytes() & capacity)] = h; } +// Overload for setting to an occupied `h2_t` rather than a special `ctrl_t`. +inline void SetCtrl(size_t i, h2_t h, size_t capacity, ctrl_t* ctrl, + const void* slot, size_t slot_size) { + SetCtrl(i, static_cast<ctrl_t>(h), capacity, ctrl, slot, slot_size); +} + +// Given the capacity of a table, computes the offset (from the start of the +// backing allocation) at which the slots begin. +inline size_t SlotOffset(size_t capacity, size_t slot_align) { + assert(IsValidCapacity(capacity)); + const size_t num_control_bytes = capacity + 1 + NumClonedBytes(); + return (num_control_bytes + slot_align - 1) & (~slot_align + 1); +} + +// Given the capacity of a table, computes the total size of the backing +// array. +inline size_t AllocSize(size_t capacity, size_t slot_size, size_t slot_align) { + return SlotOffset(capacity, slot_align) + capacity * slot_size; +} + +// A SwissTable. +// // Policy: a policy defines how to perform different operations on // the slots of the hashtable (see hash_policy_traits.h for the full interface // of policy). @@ -624,13 +974,6 @@ class raw_hash_set { auto KeyTypeCanBeHashed(const Hash& h, const key_type& k) -> decltype(h(k)); auto KeyTypeCanBeEq(const Eq& eq, const key_type& k) -> decltype(eq(k, k)); - using Layout = absl::container_internal::Layout<ctrl_t, slot_type>; - - static Layout MakeLayout(size_t capacity) { - assert(IsValidCapacity(capacity)); - return Layout(capacity + Group::kWidth + 1, capacity); - } - using AllocTraits = absl::allocator_traits<allocator_type>; using SlotAlloc = typename absl::allocator_traits< allocator_type>::template rebind_alloc<slot_type>; @@ -689,16 +1032,22 @@ class raw_hash_set { // PRECONDITION: not an end() iterator. reference operator*() const { - AssertIsFull(ctrl_); + ABSL_INTERNAL_ASSERT_IS_FULL(ctrl_, + "operator*() called on invalid iterator."); return PolicyTraits::element(slot_); } // PRECONDITION: not an end() iterator. - pointer operator->() const { return &operator*(); } + pointer operator->() const { + ABSL_INTERNAL_ASSERT_IS_FULL(ctrl_, + "operator-> called on invalid iterator."); + return &operator*(); + } // PRECONDITION: not an end() iterator. iterator& operator++() { - AssertIsFull(ctrl_); + ABSL_INTERNAL_ASSERT_IS_FULL(ctrl_, + "operator++ called on invalid iterator."); ++ctrl_; ++slot_; skip_empty_or_deleted(); @@ -724,16 +1073,20 @@ class raw_hash_set { iterator(ctrl_t* ctrl, slot_type* slot) : ctrl_(ctrl), slot_(slot) { // This assumption helps the compiler know that any non-end iterator is // not equal to any end iterator. - ABSL_INTERNAL_ASSUME(ctrl != nullptr); + ABSL_ASSUME(ctrl != nullptr); } + // Fixes up `ctrl_` to point to a full by advancing it and `slot_` until + // they reach one. + // + // If a sentinel is reached, we null both of them out instead. void skip_empty_or_deleted() { while (IsEmptyOrDeleted(*ctrl_)) { uint32_t shift = Group{ctrl_}.CountLeadingEmptyOrDeleted(); ctrl_ += shift; slot_ += shift; } - if (ABSL_PREDICT_FALSE(*ctrl_ == kSentinel)) ctrl_ = nullptr; + if (ABSL_PREDICT_FALSE(*ctrl_ == ctrl_t::kSentinel)) ctrl_ = nullptr; } ctrl_t* ctrl_ = nullptr; @@ -814,7 +1167,8 @@ class raw_hash_set { raw_hash_set(InputIter first, InputIter last, size_t bucket_count = 0, const hasher& hash = hasher(), const key_equal& eq = key_equal(), const allocator_type& alloc = allocator_type()) - : raw_hash_set(bucket_count, hash, eq, alloc) { + : raw_hash_set(SelectBucketCountForIterRange(first, last, bucket_count), + hash, eq, alloc) { insert(first, last); } @@ -902,7 +1256,8 @@ class raw_hash_set { for (const auto& v : that) { const size_t hash = PolicyTraits::apply(HashElement{hash_ref()}, v); auto target = find_first_non_full(ctrl_, hash, capacity_); - set_ctrl(target.offset, H2(hash)); + SetCtrl(target.offset, H2(hash), capacity_, ctrl_, slots_, + sizeof(slot_type)); emplace_at(target.offset, v); infoz().RecordInsert(hash, target.probe_length); } @@ -998,6 +1353,8 @@ class raw_hash_set { // past that we simply deallocate the array. if (capacity_ > 127) { destroy_slots(); + + infoz().RecordClearedReservation(); } else if (capacity_) { for (size_t i = 0; i != capacity_; ++i) { if (IsFull(ctrl_[i])) { @@ -1005,7 +1362,7 @@ class raw_hash_set { } } size_ = 0; - reset_ctrl(); + ResetCtrl(capacity_, ctrl_, slots_, sizeof(slot_type)); reset_growth_left(); } assert(empty()); @@ -1019,8 +1376,7 @@ class raw_hash_set { // m.insert(std::make_pair("abc", 42)); // TODO(cheshire): A type alias T2 is introduced as a workaround for the nvcc // bug. - template <class T, RequiresInsertable<T> = 0, - class T2 = T, + template <class T, RequiresInsertable<T> = 0, class T2 = T, typename std::enable_if<IsDecomposable<T2>::value, int>::type = 0, T* = nullptr> std::pair<iterator, bool> insert(T&& value) { @@ -1240,7 +1596,8 @@ class raw_hash_set { // This overload is necessary because otherwise erase<K>(const K&) would be // a better match if non-const iterator is passed as an argument. void erase(iterator it) { - AssertIsFull(it.ctrl_); + ABSL_INTERNAL_ASSERT_IS_FULL(it.ctrl_, + "erase() called on invalid iterator."); PolicyTraits::destroy(&alloc_ref(), it.slot_); erase_meta_only(it); } @@ -1274,7 +1631,8 @@ class raw_hash_set { } node_type extract(const_iterator position) { - AssertIsFull(position.inner_.ctrl_); + ABSL_INTERNAL_ASSERT_IS_FULL(position.inner_.ctrl_, + "extract() called on invalid iterator."); auto node = CommonAccess::Transfer<node_type>(alloc_ref(), position.inner_.slot_); erase_meta_only(position); @@ -1311,21 +1669,31 @@ class raw_hash_set { if (n == 0 && size_ == 0) { destroy_slots(); infoz().RecordStorageChanged(0, 0); + infoz().RecordClearedReservation(); return; } + // bitor is a faster way of doing `max` here. We will round up to the next // power-of-2-minus-1, so bitor is good enough. auto m = NormalizeCapacity(n | GrowthToLowerboundCapacity(size())); // n == 0 unconditionally rehashes as per the standard. if (n == 0 || m > capacity_) { resize(m); + + // This is after resize, to ensure that we have completed the allocation + // and have potentially sampled the hashtable. + infoz().RecordReservation(n); } } void reserve(size_t n) { - size_t m = GrowthToLowerboundCapacity(n); - if (m > capacity_) { + if (n > size() + growth_left()) { + size_t m = GrowthToLowerboundCapacity(n); resize(NormalizeCapacity(m)); + + // This is after resize, to ensure that we have completed the allocation + // and have potentially sampled the hashtable. + infoz().RecordReservation(n); } } @@ -1351,11 +1719,13 @@ class raw_hash_set { template <class K = key_type> void prefetch(const key_arg<K>& key) const { (void)key; -#if defined(__GNUC__) + // Avoid probing if we won't be able to prefetch the addresses received. +#ifdef ABSL_INTERNAL_HAVE_PREFETCH + prefetch_heap_block(); auto seq = probe(ctrl_, hash_ref()(key), capacity_); - __builtin_prefetch(static_cast<const void*>(ctrl_ + seq.offset())); - __builtin_prefetch(static_cast<const void*>(slots_ + seq.offset())); -#endif // __GNUC__ + base_internal::PrefetchT0(ctrl_ + seq.offset()); + base_internal::PrefetchT0(slots_ + seq.offset()); +#endif // ABSL_INTERNAL_HAVE_PREFETCH } // The API of find() has two extensions. @@ -1370,19 +1740,20 @@ class raw_hash_set { auto seq = probe(ctrl_, hash, capacity_); while (true) { Group g{ctrl_ + seq.offset()}; - for (int i : g.Match(H2(hash))) { + for (uint32_t i : g.Match(H2(hash))) { if (ABSL_PREDICT_TRUE(PolicyTraits::apply( EqualElement<K>{key, eq_ref()}, PolicyTraits::element(slots_ + seq.offset(i))))) return iterator_at(seq.offset(i)); } - if (ABSL_PREDICT_TRUE(g.MatchEmpty())) return end(); + if (ABSL_PREDICT_TRUE(g.MaskEmpty())) return end(); seq.next(); - assert(seq.index() < capacity_ && "full table!"); + assert(seq.index() <= capacity_ && "full table!"); } } template <class K = key_type> iterator find(const key_arg<K>& key) { + prefetch_heap_block(); return find(key, hash_ref()(key)); } @@ -1392,6 +1763,7 @@ class raw_hash_set { } template <class K = key_type> const_iterator find(const key_arg<K>& key) const { + prefetch_heap_block(); return find(key, hash_ref()(key)); } @@ -1441,6 +1813,14 @@ class raw_hash_set { return !(a == b); } + template <typename H> + friend typename std::enable_if<H::template is_hashable<value_type>::value, + H>::type + AbslHashValue(H h, const raw_hash_set& s) { + return H::combine(H::combine_unordered(std::move(h), s.begin(), s.end()), + s.size()); + } + friend void swap(raw_hash_set& a, raw_hash_set& b) noexcept(noexcept(a.swap(b))) { a.swap(b); @@ -1506,17 +1886,17 @@ class raw_hash_set { slot_type&& slot; }; - // "erases" the object from the container, except that it doesn't actually - // destroy the object. It only updates all the metadata of the class. - // This can be used in conjunction with Policy::transfer to move the object to - // another place. + // Erases, but does not destroy, the value pointed to by `it`. + // + // This merely updates the pertinent control byte. This can be used in + // conjunction with Policy::transfer to move the object to another place. void erase_meta_only(const_iterator it) { assert(IsFull(*it.inner_.ctrl_) && "erasing a dangling iterator"); --size_; - const size_t index = it.inner_.ctrl_ - ctrl_; + const size_t index = static_cast<size_t>(it.inner_.ctrl_ - ctrl_); const size_t index_before = (index - Group::kWidth) & capacity_; - const auto empty_after = Group(it.inner_.ctrl_).MatchEmpty(); - const auto empty_before = Group(ctrl_ + index_before).MatchEmpty(); + const auto empty_after = Group(it.inner_.ctrl_).MaskEmpty(); + const auto empty_before = Group(ctrl_ + index_before).MaskEmpty(); // We count how many consecutive non empties we have to the right and to the // left of `it`. If the sum is >= kWidth then there is at least one probe @@ -1526,11 +1906,17 @@ class raw_hash_set { static_cast<size_t>(empty_after.TrailingZeros() + empty_before.LeadingZeros()) < Group::kWidth; - set_ctrl(index, was_never_full ? kEmpty : kDeleted); + SetCtrl(index, was_never_full ? ctrl_t::kEmpty : ctrl_t::kDeleted, + capacity_, ctrl_, slots_, sizeof(slot_type)); growth_left() += was_never_full; infoz().RecordErase(); } + // Allocates a backing array for `self` and initializes its control bytes. + // This reads `capacity_` and updates all other fields based on the result of + // the allocation. + // + // This does not free the currently held array; `capacity_` must be nonzero. void initialize_slots() { assert(capacity_); // Folks with custom allocators often make unwarranted assumptions about the @@ -1545,19 +1931,24 @@ class raw_hash_set { // bound more carefully. if (std::is_same<SlotAlloc, std::allocator<slot_type>>::value && slots_ == nullptr) { - infoz() = Sample(); + infoz() = Sample(sizeof(slot_type)); } - auto layout = MakeLayout(capacity_); - char* mem = static_cast<char*>( - Allocate<Layout::Alignment()>(&alloc_ref(), layout.AllocSize())); - ctrl_ = reinterpret_cast<ctrl_t*>(layout.template Pointer<0>(mem)); - slots_ = layout.template Pointer<1>(mem); - reset_ctrl(); + char* mem = static_cast<char*>(Allocate<alignof(slot_type)>( + &alloc_ref(), + AllocSize(capacity_, sizeof(slot_type), alignof(slot_type)))); + ctrl_ = reinterpret_cast<ctrl_t*>(mem); + slots_ = reinterpret_cast<slot_type*>( + mem + SlotOffset(capacity_, alignof(slot_type))); + ResetCtrl(capacity_, ctrl_, slots_, sizeof(slot_type)); reset_growth_left(); infoz().RecordStorageChanged(size_, capacity_); } + // Destroys all slots in the backing array, frees the backing array, and + // clears all top-level book-keeping data. + // + // This essentially implements `map = raw_hash_set();`. void destroy_slots() { if (!capacity_) return; for (size_t i = 0; i != capacity_; ++i) { @@ -1565,10 +1956,12 @@ class raw_hash_set { PolicyTraits::destroy(&alloc_ref(), slots_ + i); } } - auto layout = MakeLayout(capacity_); + // Unpoison before returning the memory to the allocator. SanitizerUnpoisonMemoryRegion(slots_, sizeof(slot_type) * capacity_); - Deallocate<Layout::Alignment()>(&alloc_ref(), ctrl_, layout.AllocSize()); + Deallocate<alignof(slot_type)>( + &alloc_ref(), ctrl_, + AllocSize(capacity_, sizeof(slot_type), alignof(slot_type))); ctrl_ = EmptyGroup(); slots_ = nullptr; size_ = 0; @@ -1592,20 +1985,23 @@ class raw_hash_set { auto target = find_first_non_full(ctrl_, hash, capacity_); size_t new_i = target.offset; total_probe_length += target.probe_length; - set_ctrl(new_i, H2(hash)); + SetCtrl(new_i, H2(hash), capacity_, ctrl_, slots_, sizeof(slot_type)); PolicyTraits::transfer(&alloc_ref(), slots_ + new_i, old_slots + i); } } if (old_capacity) { SanitizerUnpoisonMemoryRegion(old_slots, sizeof(slot_type) * old_capacity); - auto layout = MakeLayout(old_capacity); - Deallocate<Layout::Alignment()>(&alloc_ref(), old_ctrl, - layout.AllocSize()); + Deallocate<alignof(slot_type)>( + &alloc_ref(), old_ctrl, + AllocSize(old_capacity, sizeof(slot_type), alignof(slot_type))); } infoz().RecordRehash(total_probe_length); } + // Prunes control bytes to remove as many tombstones as possible. + // + // See the comment on `rehash_and_grow_if_necessary()`. void drop_deletes_without_resize() ABSL_ATTRIBUTE_NOINLINE { assert(IsValidCapacity(capacity_)); assert(!is_small(capacity_)); @@ -1631,35 +2027,35 @@ class raw_hash_set { slot_type* slot = reinterpret_cast<slot_type*>(&raw); for (size_t i = 0; i != capacity_; ++i) { if (!IsDeleted(ctrl_[i])) continue; - size_t hash = PolicyTraits::apply(HashElement{hash_ref()}, - PolicyTraits::element(slots_ + i)); - auto target = find_first_non_full(ctrl_, hash, capacity_); - size_t new_i = target.offset; + const size_t hash = PolicyTraits::apply( + HashElement{hash_ref()}, PolicyTraits::element(slots_ + i)); + const FindInfo target = find_first_non_full(ctrl_, hash, capacity_); + const size_t new_i = target.offset; total_probe_length += target.probe_length; // Verify if the old and new i fall within the same group wrt the hash. // If they do, we don't need to move the object as it falls already in the // best probe we can. - const auto probe_index = [&](size_t pos) { - return ((pos - probe(ctrl_, hash, capacity_).offset()) & capacity_) / - Group::kWidth; + const size_t probe_offset = probe(ctrl_, hash, capacity_).offset(); + const auto probe_index = [probe_offset, this](size_t pos) { + return ((pos - probe_offset) & capacity_) / Group::kWidth; }; // Element doesn't move. if (ABSL_PREDICT_TRUE(probe_index(new_i) == probe_index(i))) { - set_ctrl(i, H2(hash)); + SetCtrl(i, H2(hash), capacity_, ctrl_, slots_, sizeof(slot_type)); continue; } if (IsEmpty(ctrl_[new_i])) { // Transfer element to the empty spot. - // set_ctrl poisons/unpoisons the slots so we have to call it at the + // SetCtrl poisons/unpoisons the slots so we have to call it at the // right time. - set_ctrl(new_i, H2(hash)); + SetCtrl(new_i, H2(hash), capacity_, ctrl_, slots_, sizeof(slot_type)); PolicyTraits::transfer(&alloc_ref(), slots_ + new_i, slots_ + i); - set_ctrl(i, kEmpty); + SetCtrl(i, ctrl_t::kEmpty, capacity_, ctrl_, slots_, sizeof(slot_type)); } else { assert(IsDeleted(ctrl_[new_i])); - set_ctrl(new_i, H2(hash)); + SetCtrl(new_i, H2(hash), capacity_, ctrl_, slots_, sizeof(slot_type)); // Until we are done rehashing, DELETED marks previously FULL slots. // Swap i and new_i elements. PolicyTraits::transfer(&alloc_ref(), slot, slots_ + i); @@ -1672,11 +2068,58 @@ class raw_hash_set { infoz().RecordRehash(total_probe_length); } + // Called whenever the table *might* need to conditionally grow. + // + // This function is an optimization opportunity to perform a rehash even when + // growth is unnecessary, because vacating tombstones is beneficial for + // performance in the long-run. void rehash_and_grow_if_necessary() { if (capacity_ == 0) { resize(1); - } else if (size() <= CapacityToGrowth(capacity()) / 2) { + } else if (capacity_ > Group::kWidth && + // Do these calcuations in 64-bit to avoid overflow. + size() * uint64_t{32} <= capacity_ * uint64_t{25}) { // Squash DELETED without growing if there is enough capacity. + // + // Rehash in place if the current size is <= 25/32 of capacity_. + // Rationale for such a high factor: 1) drop_deletes_without_resize() is + // faster than resize, and 2) it takes quite a bit of work to add + // tombstones. In the worst case, seems to take approximately 4 + // insert/erase pairs to create a single tombstone and so if we are + // rehashing because of tombstones, we can afford to rehash-in-place as + // long as we are reclaiming at least 1/8 the capacity without doing more + // than 2X the work. (Where "work" is defined to be size() for rehashing + // or rehashing in place, and 1 for an insert or erase.) But rehashing in + // place is faster per operation than inserting or even doubling the size + // of the table, so we actually afford to reclaim even less space from a + // resize-in-place. The decision is to rehash in place if we can reclaim + // at about 1/8th of the usable capacity (specifically 3/28 of the + // capacity) which means that the total cost of rehashing will be a small + // fraction of the total work. + // + // Here is output of an experiment using the BM_CacheInSteadyState + // benchmark running the old case (where we rehash-in-place only if we can + // reclaim at least 7/16*capacity_) vs. this code (which rehashes in place + // if we can recover 3/32*capacity_). + // + // Note that although in the worst-case number of rehashes jumped up from + // 15 to 190, but the number of operations per second is almost the same. + // + // Abridged output of running BM_CacheInSteadyState benchmark from + // raw_hash_set_benchmark. N is the number of insert/erase operations. + // + // | OLD (recover >= 7/16 | NEW (recover >= 3/32) + // size | N/s LoadFactor NRehashes | N/s LoadFactor NRehashes + // 448 | 145284 0.44 18 | 140118 0.44 19 + // 493 | 152546 0.24 11 | 151417 0.48 28 + // 538 | 151439 0.26 11 | 151152 0.53 38 + // 583 | 151765 0.28 11 | 150572 0.57 50 + // 628 | 150241 0.31 11 | 150853 0.61 66 + // 672 | 149602 0.33 12 | 150110 0.66 90 + // 717 | 149998 0.35 12 | 149531 0.70 129 + // 762 | 149836 0.37 13 | 148559 0.74 190 + // 807 | 149736 0.39 14 | 151107 0.39 14 + // 852 | 150204 0.42 15 | 151019 0.42 15 drop_deletes_without_resize(); } else { // Otherwise grow the container. @@ -1689,14 +2132,14 @@ class raw_hash_set { auto seq = probe(ctrl_, hash, capacity_); while (true) { Group g{ctrl_ + seq.offset()}; - for (int i : g.Match(H2(hash))) { + for (uint32_t i : g.Match(H2(hash))) { if (ABSL_PREDICT_TRUE(PolicyTraits::element(slots_ + seq.offset(i)) == elem)) return true; } - if (ABSL_PREDICT_TRUE(g.MatchEmpty())) return false; + if (ABSL_PREDICT_TRUE(g.MaskEmpty())) return false; seq.next(); - assert(seq.index() < capacity_ && "full table!"); + assert(seq.index() <= capacity_ && "full table!"); } return false; } @@ -1714,25 +2157,33 @@ class raw_hash_set { } protected: + // Attempts to find `key` in the table; if it isn't found, returns a slot that + // the value can be inserted into, with the control byte already set to + // `key`'s H2. template <class K> std::pair<size_t, bool> find_or_prepare_insert(const K& key) { + prefetch_heap_block(); auto hash = hash_ref()(key); auto seq = probe(ctrl_, hash, capacity_); while (true) { Group g{ctrl_ + seq.offset()}; - for (int i : g.Match(H2(hash))) { + for (uint32_t i : g.Match(H2(hash))) { if (ABSL_PREDICT_TRUE(PolicyTraits::apply( EqualElement<K>{key, eq_ref()}, PolicyTraits::element(slots_ + seq.offset(i))))) return {seq.offset(i), false}; } - if (ABSL_PREDICT_TRUE(g.MatchEmpty())) break; + if (ABSL_PREDICT_TRUE(g.MaskEmpty())) break; seq.next(); - assert(seq.index() < capacity_ && "full table!"); + assert(seq.index() <= capacity_ && "full table!"); } return {prepare_insert(hash), true}; } + // Given the hash of a value not currently in the table, finds the next + // viable slot index to insert it at. + // + // REQUIRES: At least one non-full slot available. size_t prepare_insert(size_t hash) ABSL_ATTRIBUTE_NOINLINE { auto target = find_first_non_full(ctrl_, hash, capacity_); if (ABSL_PREDICT_FALSE(growth_left() == 0 && @@ -1742,7 +2193,8 @@ class raw_hash_set { } ++size_; growth_left() -= IsEmpty(ctrl_[target.offset]); - set_ctrl(target.offset, H2(hash)); + SetCtrl(target.offset, H2(hash), capacity_, ctrl_, slots_, + sizeof(slot_type)); infoz().RecordInsert(hash, target.probe_length); return target.offset; } @@ -1771,35 +2223,29 @@ class raw_hash_set { private: friend struct RawHashSetTestOnlyAccess; - // Reset all ctrl bytes back to kEmpty, except the sentinel. - void reset_ctrl() { - std::memset(ctrl_, kEmpty, capacity_ + Group::kWidth); - ctrl_[capacity_] = kSentinel; - SanitizerPoisonMemoryRegion(slots_, sizeof(slot_type) * capacity_); - } - void reset_growth_left() { growth_left() = CapacityToGrowth(capacity()) - size_; } - // Sets the control byte, and if `i < Group::kWidth`, set the cloned byte at - // the end too. - void set_ctrl(size_t i, ctrl_t h) { - assert(i < capacity_); - - if (IsFull(h)) { - SanitizerUnpoisonObject(slots_ + i); - } else { - SanitizerPoisonObject(slots_ + i); - } + // The number of slots we can still fill without needing to rehash. + // + // This is stored separately due to tombstones: we do not include tombstones + // in the growth capacity, because we'd like to rehash when the table is + // otherwise filled with tombstones: otherwise, probe sequences might get + // unacceptably long without triggering a rehash. Callers can also force a + // rehash via the standard `rehash(0)`, which will recompute this value as a + // side-effect. + // + // See `CapacityToGrowth()`. + size_t& growth_left() { return settings_.template get<0>(); } - ctrl_[i] = h; - ctrl_[((i - Group::kWidth) & capacity_) + 1 + - ((Group::kWidth - 1) & capacity_)] = h; + // Prefetch the heap-allocated memory region to resolve potential TLB misses. + // This is intended to overlap with execution of calculating the hash for a + // key. + void prefetch_heap_block() const { + base_internal::PrefetchT2(ctrl_); } - size_t& growth_left() { return settings_.template get<0>(); } - HashtablezInfoHandle& infoz() { return settings_.template get<1>(); } hasher& hash_ref() { return settings_.template get<2>(); } @@ -1814,26 +2260,41 @@ class raw_hash_set { // TODO(alkis): Investigate removing some of these fields: // - ctrl/slots can be derived from each other // - size can be moved into the slot array - ctrl_t* ctrl_ = EmptyGroup(); // [(capacity + 1) * ctrl_t] - slot_type* slots_ = nullptr; // [capacity * slot_type] - size_t size_ = 0; // number of full slots - size_t capacity_ = 0; // total number of slots + + // The control bytes (and, also, a pointer to the base of the backing array). + // + // This contains `capacity_ + 1 + NumClonedBytes()` entries, even + // when the table is empty (hence EmptyGroup). + ctrl_t* ctrl_ = EmptyGroup(); + // The beginning of the slots, located at `SlotOffset()` bytes after + // `ctrl_`. May be null for empty tables. + slot_type* slots_ = nullptr; + + // The number of filled slots. + size_t size_ = 0; + + // The total number of available slots. + size_t capacity_ = 0; absl::container_internal::CompressedTuple<size_t /* growth_left */, HashtablezInfoHandle, hasher, key_equal, allocator_type> - settings_{0, HashtablezInfoHandle{}, hasher{}, key_equal{}, + settings_{0u, HashtablezInfoHandle{}, hasher{}, key_equal{}, allocator_type{}}; }; // Erases all elements that satisfy the predicate `pred` from the container `c`. template <typename P, typename H, typename E, typename A, typename Predicate> -void EraseIf(Predicate pred, raw_hash_set<P, H, E, A>* c) { +typename raw_hash_set<P, H, E, A>::size_type EraseIf( + Predicate& pred, raw_hash_set<P, H, E, A>* c) { + const auto initial_size = c->size(); for (auto it = c->begin(), last = c->end(); it != last;) { - auto copy_it = it++; - if (pred(*copy_it)) { - c->erase(copy_it); + if (pred(*it)) { + c->erase(it++); + } else { + ++it; } } + return initial_size - c->size(); } namespace hashtable_debug_internal { @@ -1849,7 +2310,7 @@ struct HashtableDebugAccess<Set, absl::void_t<typename Set::raw_hash_set>> { auto seq = probe(set.ctrl_, hash, set.capacity_); while (true) { container_internal::Group g{set.ctrl_ + seq.offset()}; - for (int i : g.Match(container_internal::H2(hash))) { + for (uint32_t i : g.Match(container_internal::H2(hash))) { if (Traits::apply( typename Set::template EqualElement<typename Set::key_type>{ key, set.eq_ref()}, @@ -1857,7 +2318,7 @@ struct HashtableDebugAccess<Set, absl::void_t<typename Set::raw_hash_set>> { return num_probes; ++num_probes; } - if (g.MatchEmpty()) return num_probes; + if (g.MaskEmpty()) return num_probes; seq.next(); ++num_probes; } @@ -1866,8 +2327,7 @@ struct HashtableDebugAccess<Set, absl::void_t<typename Set::raw_hash_set>> { static size_t AllocatedByteSize(const Set& c) { size_t capacity = c.capacity_; if (capacity == 0) return 0; - auto layout = Set::MakeLayout(capacity); - size_t m = layout.AllocSize(); + size_t m = AllocSize(capacity, sizeof(Slot), alignof(Slot)); size_t per_slot = Traits::space_used(static_cast<const Slot*>(nullptr)); if (per_slot != ~size_t{}) { @@ -1885,8 +2345,8 @@ struct HashtableDebugAccess<Set, absl::void_t<typename Set::raw_hash_set>> { static size_t LowerBoundAllocatedByteSize(size_t size) { size_t capacity = GrowthToLowerboundCapacity(size); if (capacity == 0) return 0; - auto layout = Set::MakeLayout(NormalizeCapacity(capacity)); - size_t m = layout.AllocSize(); + size_t m = + AllocSize(NormalizeCapacity(capacity), sizeof(Slot), alignof(Slot)); size_t per_slot = Traits::space_used(static_cast<const Slot*>(nullptr)); if (per_slot != ~size_t{}) { m += per_slot * size; @@ -1900,4 +2360,6 @@ struct HashtableDebugAccess<Set, absl::void_t<typename Set::raw_hash_set>> { ABSL_NAMESPACE_END } // namespace absl +#undef ABSL_INTERNAL_ASSERT_IS_FULL + #endif // ABSL_CONTAINER_INTERNAL_RAW_HASH_SET_H_ diff --git a/absl/container/internal/raw_hash_set_benchmark.cc b/absl/container/internal/raw_hash_set_benchmark.cc index f9be2c5a..47dc9048 100644 --- a/absl/container/internal/raw_hash_set_benchmark.cc +++ b/absl/container/internal/raw_hash_set_benchmark.cc @@ -254,6 +254,23 @@ void BM_CopyAssign(benchmark::State& state) { } BENCHMARK(BM_CopyAssign)->Range(128, 4096); +void BM_RangeCtor(benchmark::State& state) { + std::random_device rd; + std::mt19937 rng(rd()); + std::uniform_int_distribution<uint64_t> dist(0, ~uint64_t{}); + std::vector<int> values; + const size_t desired_size = state.range(0); + while (values.size() < desired_size) { + values.emplace_back(dist(rng)); + } + + for (auto unused : state) { + IntTable t{values.begin(), values.end()}; + benchmark::DoNotOptimize(t); + } +} +BENCHMARK(BM_RangeCtor)->Range(128, 65536); + void BM_NoOpReserveIntTable(benchmark::State& state) { IntTable t; t.reserve(100000); @@ -298,56 +315,79 @@ void BM_ReserveStringTable(benchmark::State& state) { } BENCHMARK(BM_ReserveStringTable)->Range(128, 4096); +// Like std::iota, except that ctrl_t doesn't support operator++. +template <typename CtrlIter> +void Iota(CtrlIter begin, CtrlIter end, int value) { + for (; begin != end; ++begin, ++value) { + *begin = static_cast<ctrl_t>(value); + } +} + void BM_Group_Match(benchmark::State& state) { std::array<ctrl_t, Group::kWidth> group; - std::iota(group.begin(), group.end(), -4); + Iota(group.begin(), group.end(), -4); Group g{group.data()}; h2_t h = 1; for (auto _ : state) { ::benchmark::DoNotOptimize(h); + ::benchmark::DoNotOptimize(g); ::benchmark::DoNotOptimize(g.Match(h)); } } BENCHMARK(BM_Group_Match); -void BM_Group_MatchEmpty(benchmark::State& state) { +void BM_Group_MaskEmpty(benchmark::State& state) { std::array<ctrl_t, Group::kWidth> group; - std::iota(group.begin(), group.end(), -4); + Iota(group.begin(), group.end(), -4); Group g{group.data()}; - for (auto _ : state) ::benchmark::DoNotOptimize(g.MatchEmpty()); + for (auto _ : state) { + ::benchmark::DoNotOptimize(g); + ::benchmark::DoNotOptimize(g.MaskEmpty()); + } } -BENCHMARK(BM_Group_MatchEmpty); +BENCHMARK(BM_Group_MaskEmpty); -void BM_Group_MatchEmptyOrDeleted(benchmark::State& state) { +void BM_Group_MaskEmptyOrDeleted(benchmark::State& state) { std::array<ctrl_t, Group::kWidth> group; - std::iota(group.begin(), group.end(), -4); + Iota(group.begin(), group.end(), -4); Group g{group.data()}; - for (auto _ : state) ::benchmark::DoNotOptimize(g.MatchEmptyOrDeleted()); + for (auto _ : state) { + ::benchmark::DoNotOptimize(g); + ::benchmark::DoNotOptimize(g.MaskEmptyOrDeleted()); + } } -BENCHMARK(BM_Group_MatchEmptyOrDeleted); +BENCHMARK(BM_Group_MaskEmptyOrDeleted); void BM_Group_CountLeadingEmptyOrDeleted(benchmark::State& state) { std::array<ctrl_t, Group::kWidth> group; - std::iota(group.begin(), group.end(), -2); + Iota(group.begin(), group.end(), -2); Group g{group.data()}; - for (auto _ : state) + for (auto _ : state) { + ::benchmark::DoNotOptimize(g); ::benchmark::DoNotOptimize(g.CountLeadingEmptyOrDeleted()); + } } BENCHMARK(BM_Group_CountLeadingEmptyOrDeleted); void BM_Group_MatchFirstEmptyOrDeleted(benchmark::State& state) { std::array<ctrl_t, Group::kWidth> group; - std::iota(group.begin(), group.end(), -2); + Iota(group.begin(), group.end(), -2); Group g{group.data()}; - for (auto _ : state) ::benchmark::DoNotOptimize(*g.MatchEmptyOrDeleted()); + for (auto _ : state) { + ::benchmark::DoNotOptimize(g); + ::benchmark::DoNotOptimize(g.MaskEmptyOrDeleted().LowestBitSet()); + } } BENCHMARK(BM_Group_MatchFirstEmptyOrDeleted); void BM_DropDeletes(benchmark::State& state) { constexpr size_t capacity = (1 << 20) - 1; std::vector<ctrl_t> ctrl(capacity + 1 + Group::kWidth); - ctrl[capacity] = kSentinel; - std::vector<ctrl_t> pattern = {kEmpty, 2, kDeleted, 2, kEmpty, 1, kDeleted}; + ctrl[capacity] = ctrl_t::kSentinel; + std::vector<ctrl_t> pattern = {ctrl_t::kEmpty, static_cast<ctrl_t>(2), + ctrl_t::kDeleted, static_cast<ctrl_t>(2), + ctrl_t::kEmpty, static_cast<ctrl_t>(1), + ctrl_t::kDeleted}; for (size_t i = 0; i != capacity; ++i) { ctrl[i] = pattern[i % pattern.size()]; } @@ -378,6 +418,12 @@ bool CodegenAbslRawHashSetInt64FindNeEnd( return table->find(key) != table->end(); } +auto CodegenAbslRawHashSetInt64Insert(absl::container_internal::IntTable* table, + int64_t key) + -> decltype(table->insert(key)) { + return table->insert(key); +} + bool CodegenAbslRawHashSetInt64Contains( absl::container_internal::IntTable* table, int64_t key) { return table->contains(key); @@ -391,6 +437,7 @@ void CodegenAbslRawHashSetInt64Iterate( int odr = (::benchmark::DoNotOptimize(std::make_tuple( &CodegenAbslRawHashSetInt64Find, &CodegenAbslRawHashSetInt64FindNeEnd, + &CodegenAbslRawHashSetInt64Insert, &CodegenAbslRawHashSetInt64Contains, &CodegenAbslRawHashSetInt64Iterate)), 1); diff --git a/absl/container/internal/raw_hash_set_test.cc b/absl/container/internal/raw_hash_set_test.cc index 7dac65a0..f77ffbc1 100644 --- a/absl/container/internal/raw_hash_set_test.cc +++ b/absl/container/internal/raw_hash_set_test.cc @@ -31,6 +31,7 @@ #include "absl/base/attributes.h" #include "absl/base/config.h" #include "absl/base/internal/cycleclock.h" +#include "absl/base/internal/prefetch.h" #include "absl/base/internal/raw_logging.h" #include "absl/container/internal/container_memory.h" #include "absl/container/internal/hash_function_defaults.h" @@ -58,6 +59,9 @@ using ::testing::Lt; using ::testing::Pair; using ::testing::UnorderedElementsAre; +// Convenience function to static cast to ctrl_t. +ctrl_t CtrlT(int i) { return static_cast<ctrl_t>(i); } + TEST(Util, NormalizeCapacity) { EXPECT_EQ(1, NormalizeCapacity(0)); EXPECT_EQ(1, NormalizeCapacity(1)); @@ -170,15 +174,19 @@ TEST(Group, EmptyGroup) { TEST(Group, Match) { if (Group::kWidth == 16) { - ctrl_t group[] = {kEmpty, 1, kDeleted, 3, kEmpty, 5, kSentinel, 7, - 7, 5, 3, 1, 1, 1, 1, 1}; + ctrl_t group[] = {ctrl_t::kEmpty, CtrlT(1), ctrl_t::kDeleted, CtrlT(3), + ctrl_t::kEmpty, CtrlT(5), ctrl_t::kSentinel, CtrlT(7), + CtrlT(7), CtrlT(5), CtrlT(3), CtrlT(1), + CtrlT(1), CtrlT(1), CtrlT(1), CtrlT(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)); } else if (Group::kWidth == 8) { - ctrl_t group[] = {kEmpty, 1, 2, kDeleted, 2, 1, kSentinel, 1}; + ctrl_t group[] = {ctrl_t::kEmpty, CtrlT(1), CtrlT(2), + ctrl_t::kDeleted, CtrlT(2), CtrlT(1), + ctrl_t::kSentinel, CtrlT(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)); @@ -187,27 +195,39 @@ TEST(Group, Match) { } } -TEST(Group, MatchEmpty) { +TEST(Group, MaskEmpty) { if (Group::kWidth == 16) { - 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)); + ctrl_t group[] = {ctrl_t::kEmpty, CtrlT(1), ctrl_t::kDeleted, CtrlT(3), + ctrl_t::kEmpty, CtrlT(5), ctrl_t::kSentinel, CtrlT(7), + CtrlT(7), CtrlT(5), CtrlT(3), CtrlT(1), + CtrlT(1), CtrlT(1), CtrlT(1), CtrlT(1)}; + EXPECT_THAT(Group{group}.MaskEmpty().LowestBitSet(), 0); + EXPECT_THAT(Group{group}.MaskEmpty().HighestBitSet(), 4); } else if (Group::kWidth == 8) { - ctrl_t group[] = {kEmpty, 1, 2, kDeleted, 2, 1, kSentinel, 1}; - EXPECT_THAT(Group{group}.MatchEmpty(), ElementsAre(0)); + ctrl_t group[] = {ctrl_t::kEmpty, CtrlT(1), CtrlT(2), + ctrl_t::kDeleted, CtrlT(2), CtrlT(1), + ctrl_t::kSentinel, CtrlT(1)}; + EXPECT_THAT(Group{group}.MaskEmpty().LowestBitSet(), 0); + EXPECT_THAT(Group{group}.MaskEmpty().HighestBitSet(), 0); } else { FAIL() << "No test coverage for Group::kWidth==" << Group::kWidth; } } -TEST(Group, MatchEmptyOrDeleted) { +TEST(Group, MaskEmptyOrDeleted) { if (Group::kWidth == 16) { - 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)); + ctrl_t group[] = {ctrl_t::kEmpty, CtrlT(1), ctrl_t::kEmpty, CtrlT(3), + ctrl_t::kDeleted, CtrlT(5), ctrl_t::kSentinel, CtrlT(7), + CtrlT(7), CtrlT(5), CtrlT(3), CtrlT(1), + CtrlT(1), CtrlT(1), CtrlT(1), CtrlT(1)}; + EXPECT_THAT(Group{group}.MaskEmptyOrDeleted().LowestBitSet(), 0); + EXPECT_THAT(Group{group}.MaskEmptyOrDeleted().HighestBitSet(), 4); } else if (Group::kWidth == 8) { - ctrl_t group[] = {kEmpty, 1, 2, kDeleted, 2, 1, kSentinel, 1}; - EXPECT_THAT(Group{group}.MatchEmptyOrDeleted(), ElementsAre(0, 3)); + ctrl_t group[] = {ctrl_t::kEmpty, CtrlT(1), CtrlT(2), + ctrl_t::kDeleted, CtrlT(2), CtrlT(1), + ctrl_t::kSentinel, CtrlT(1)}; + EXPECT_THAT(Group{group}.MaskEmptyOrDeleted().LowestBitSet(), 0); + EXPECT_THAT(Group{group}.MaskEmptyOrDeleted().HighestBitSet(), 3); } else { FAIL() << "No test coverage for Group::kWidth==" << Group::kWidth; } @@ -217,28 +237,32 @@ 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}; + ctrl[kCapacity] = ctrl_t::kSentinel; + std::vector<ctrl_t> pattern = { + ctrl_t::kEmpty, CtrlT(2), ctrl_t::kDeleted, CtrlT(2), + ctrl_t::kEmpty, CtrlT(1), ctrl_t::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) { + ASSERT_EQ(ctrl[kCapacity], ctrl_t::kSentinel); + for (size_t i = 0; i < kCapacity + 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; + if (i == kCapacity) expected = ctrl_t::kSentinel; + if (expected == ctrl_t::kDeleted) expected = ctrl_t::kEmpty; + if (IsFull(expected)) expected = ctrl_t::kDeleted; EXPECT_EQ(ctrl[i], expected) - << i << " " << int{pattern[i % pattern.size()]}; + << i << " " << static_cast<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}; + const std::vector<ctrl_t> empty_examples = {ctrl_t::kEmpty, ctrl_t::kDeleted}; + const std::vector<ctrl_t> full_examples = { + CtrlT(0), CtrlT(1), CtrlT(2), CtrlT(3), + CtrlT(5), CtrlT(9), CtrlT(127), ctrl_t::kSentinel}; for (ctrl_t empty : empty_examples) { std::vector<ctrl_t> e(Group::kWidth, empty); @@ -294,6 +318,7 @@ struct ValuePolicy { }; using IntPolicy = ValuePolicy<int64_t>; +using Uint8Policy = ValuePolicy<uint8_t>; class StringPolicy { template <class F, class K, class V, @@ -374,6 +399,13 @@ struct IntTable using Base::Base; }; +struct Uint8Table + : raw_hash_set<Uint8Policy, container_internal::hash_default_hash<uint8_t>, + std::equal_to<uint8_t>, std::allocator<uint8_t>> { + using Base = typename Uint8Table::raw_hash_set; + using Base::Base; +}; + template <typename T> struct CustomAlloc : std::allocator<T> { CustomAlloc() {} @@ -541,6 +573,37 @@ TEST(Table, InsertCollisionAndFindAfterDelete) { EXPECT_TRUE(t.empty()); } +TEST(Table, InsertWithinCapacity) { + IntTable t; + t.reserve(10); + const size_t original_capacity = t.capacity(); + const auto addr = [&](int i) { + return reinterpret_cast<uintptr_t>(&*t.find(i)); + }; + // Inserting an element does not change capacity. + t.insert(0); + EXPECT_THAT(t.capacity(), original_capacity); + const uintptr_t original_addr_0 = addr(0); + // Inserting another element does not rehash. + t.insert(1); + EXPECT_THAT(t.capacity(), original_capacity); + EXPECT_THAT(addr(0), original_addr_0); + // Inserting lots of duplicate elements does not rehash. + for (int i = 0; i < 100; ++i) { + t.insert(i % 10); + } + EXPECT_THAT(t.capacity(), original_capacity); + EXPECT_THAT(addr(0), original_addr_0); + // Inserting a range of duplicate elements does not rehash. + std::vector<int> dup_range; + for (int i = 0; i < 100; ++i) { + dup_range.push_back(i % 10); + } + t.insert(dup_range.begin(), dup_range.end()); + EXPECT_THAT(t.capacity(), original_capacity); + EXPECT_THAT(addr(0), original_addr_0); +} + TEST(Table, LazyEmplace) { StringTable t; bool called = false; @@ -588,28 +651,53 @@ TEST(Table, Contains2) { } int decompose_constructed; +int decompose_copy_constructed; +int decompose_copy_assigned; +int decompose_move_constructed; +int decompose_move_assigned; struct DecomposeType { - DecomposeType(int i) : i(i) { // NOLINT + DecomposeType(int i = 0) : i(i) { // NOLINT ++decompose_constructed; } explicit DecomposeType(const char* d) : DecomposeType(*d) {} + DecomposeType(const DecomposeType& other) : i(other.i) { + ++decompose_copy_constructed; + } + DecomposeType& operator=(const DecomposeType& other) { + ++decompose_copy_assigned; + i = other.i; + return *this; + } + DecomposeType(DecomposeType&& other) : i(other.i) { + ++decompose_move_constructed; + } + DecomposeType& operator=(DecomposeType&& other) { + ++decompose_move_assigned; + i = other.i; + return *this; + } + int i; }; struct DecomposeHash { using is_transparent = void; - size_t operator()(DecomposeType a) const { return a.i; } + size_t operator()(const 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; } + bool operator()(const DecomposeType& a, const DecomposeType& b) const { + return a.i == b.i; + } + bool operator()(const DecomposeType& a, int b) const { return a.i == b; } + bool operator()(const DecomposeType& a, const char* b) const { + return a.i == *b; + } }; struct DecomposePolicy { @@ -619,9 +707,9 @@ struct DecomposePolicy { template <typename T> static void construct(void*, DecomposeType* slot, T&& v) { - *slot = DecomposeType(std::forward<T>(v)); + ::new (slot) DecomposeType(std::forward<T>(v)); } - static void destroy(void*, DecomposeType*) {} + static void destroy(void*, DecomposeType* slot) { slot->~DecomposeType(); } static DecomposeType& element(slot_type* slot) { return *slot; } template <class F, class T> @@ -636,8 +724,13 @@ void TestDecompose(bool construct_three) { const int one = 1; const char* three_p = "3"; const auto& three = three_p; + const int elem_vector_count = 256; + std::vector<DecomposeType> elem_vector(elem_vector_count, DecomposeType{0}); + std::iota(elem_vector.begin(), elem_vector.end(), 0); - raw_hash_set<DecomposePolicy, Hash, Eq, std::allocator<int>> set1; + using DecomposeSet = + raw_hash_set<DecomposePolicy, Hash, Eq, std::allocator<int>>; + DecomposeSet set1; decompose_constructed = 0; int expected_constructed = 0; @@ -695,20 +788,72 @@ void TestDecompose(bool construct_three) { expected_constructed += construct_three; EXPECT_EQ(expected_constructed, decompose_constructed); } + + decompose_copy_constructed = 0; + decompose_copy_assigned = 0; + decompose_move_constructed = 0; + decompose_move_assigned = 0; + int expected_copy_constructed = 0; + int expected_move_constructed = 0; + { // raw_hash_set(first, last) with random-access iterators + DecomposeSet set2(elem_vector.begin(), elem_vector.end()); + // Expect exactly one copy-constructor call for each element if no + // rehashing is done. + expected_copy_constructed += elem_vector_count; + EXPECT_EQ(expected_copy_constructed, decompose_copy_constructed); + EXPECT_EQ(expected_move_constructed, decompose_move_constructed); + EXPECT_EQ(0, decompose_move_assigned); + EXPECT_EQ(0, decompose_copy_assigned); + } + + { // raw_hash_set(first, last) with forward iterators + std::list<DecomposeType> elem_list(elem_vector.begin(), elem_vector.end()); + expected_copy_constructed = decompose_copy_constructed; + DecomposeSet set2(elem_list.begin(), elem_list.end()); + // Expect exactly N elements copied into set, expect at most 2*N elements + // moving internally for all resizing needed (for a growth factor of 2). + expected_copy_constructed += elem_vector_count; + EXPECT_EQ(expected_copy_constructed, decompose_copy_constructed); + expected_move_constructed += elem_vector_count; + EXPECT_LT(expected_move_constructed, decompose_move_constructed); + expected_move_constructed += elem_vector_count; + EXPECT_GE(expected_move_constructed, decompose_move_constructed); + EXPECT_EQ(0, decompose_move_assigned); + EXPECT_EQ(0, decompose_copy_assigned); + expected_copy_constructed = decompose_copy_constructed; + expected_move_constructed = decompose_move_constructed; + } + + { // insert(first, last) + DecomposeSet set2; + set2.insert(elem_vector.begin(), elem_vector.end()); + // Expect exactly N elements copied into set, expect at most 2*N elements + // moving internally for all resizing needed (for a growth factor of 2). + const int expected_new_elements = elem_vector_count; + const int expected_max_element_moves = 2 * elem_vector_count; + expected_copy_constructed += expected_new_elements; + EXPECT_EQ(expected_copy_constructed, decompose_copy_constructed); + expected_move_constructed += expected_max_element_moves; + EXPECT_GE(expected_move_constructed, decompose_move_constructed); + EXPECT_EQ(0, decompose_move_assigned); + EXPECT_EQ(0, decompose_copy_assigned); + expected_copy_constructed = decompose_copy_constructed; + expected_move_constructed = decompose_move_constructed; + } } TEST(Table, Decompose) { TestDecompose<DecomposeHash, DecomposeEq>(false); struct TransparentHashIntOverload { - size_t operator()(DecomposeType a) const { return a.i; } + size_t operator()(const DecomposeType& a) const { return a.i; } size_t operator()(int a) const { return a; } }; struct TransparentEqIntOverload { - bool operator()(DecomposeType a, DecomposeType b) const { + bool operator()(const DecomposeType& a, const DecomposeType& b) const { return a.i == b.i; } - bool operator()(DecomposeType a, int b) const { return a.i == b; } + bool operator()(const DecomposeType& a, int b) const { return a.i == b; } }; TestDecompose<TransparentHashIntOverload, DecomposeEq>(true); TestDecompose<TransparentHashIntOverload, TransparentEqIntOverload>(true); @@ -750,7 +895,7 @@ TEST(Table, RehashWithNoResize) { 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. + // All elements removed from full groups will be marked as ctrl_t::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) { @@ -1104,7 +1249,7 @@ ExpectedStats XorSeedExpectedStats() { case 16: if (kRandomizesInserts) { return {0.1, - 1.0, + 2.0, {{0.95, 0.1}}, {{0.95, 0}, {0.99, 1}, {0.999, 8}, {0.9999, 15}}}; } else { @@ -1118,6 +1263,7 @@ ExpectedStats XorSeedExpectedStats() { return {}; } +// TODO(b/80415403): Figure out why this test is so flaky, esp. on MSVC TEST(Table, DISABLED_EnsureNonQuadraticTopNXorSeedByProbeSeqLength) { ProbeStatsPerSize stats; std::vector<size_t> sizes = {Group::kWidth << 5, Group::kWidth << 10}; @@ -1190,17 +1336,17 @@ ExpectedStats LinearTransformExpectedStats() { {{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}}}; + return {0.4, + 0.6, + {{0.95, 0.5}}, + {{0.95, 1}, {0.99, 14}, {0.999, 23}, {0.9999, 26}}}; } 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}}}; + {{0.95, 1}, {0.99, 2}, {0.999, 9}, {0.9999, 15}}}; } else { return {0.05, 0.2, @@ -1212,6 +1358,7 @@ ExpectedStats LinearTransformExpectedStats() { return {}; } +// TODO(b/80415403): Figure out why this test is so flaky. TEST(Table, DISABLED_EnsureNonQuadraticTopNLinearTransformByProbeSeqLength) { ProbeStatsPerSize stats; std::vector<size_t> sizes = {Group::kWidth << 5, Group::kWidth << 10}; @@ -1888,7 +2035,7 @@ TEST(TableDeathTest, EraseOfEndAsserts) { IntTable t; // Extra simple "regexp" as regexp support is highly varied across platforms. - constexpr char kDeathMsg[] = "Invalid operation on iterator"; + constexpr char kDeathMsg[] = "erase.. called on invalid iterator"; EXPECT_DEATH_IF_SUPPORTED(t.erase(t.end()), kDeathMsg); } @@ -1898,7 +2045,7 @@ TEST(RawHashSamplerTest, Sample) { SetHashtablezEnabled(true); SetHashtablezSampleParameter(100); - auto& sampler = HashtablezSampler::Global(); + auto& sampler = GlobalHashtablezSampler(); size_t start_size = 0; std::unordered_set<const HashtablezInfo*> preexisting_info; start_size += sampler.Iterate([&](const HashtablezInfo& info) { @@ -1909,16 +2056,33 @@ TEST(RawHashSamplerTest, Sample) { std::vector<IntTable> tables; for (int i = 0; i < 1000000; ++i) { tables.emplace_back(); + + const bool do_reserve = (i % 10 > 5); + const bool do_rehash = !do_reserve && (i % 10 > 0); + + if (do_reserve) { + // Don't reserve on all tables. + tables.back().reserve(10 * (i % 10)); + } + tables.back().insert(1); tables.back().insert(i % 5); + + if (do_rehash) { + // Rehash some other tables. + tables.back().rehash(10 * (i % 10)); + } } size_t end_size = 0; std::unordered_map<size_t, int> observed_checksums; + std::unordered_map<ssize_t, int> reservations; end_size += sampler.Iterate([&](const HashtablezInfo& info) { if (preexisting_info.count(&info) == 0) { observed_checksums[info.hashes_bitwise_xor.load( std::memory_order_relaxed)]++; + reservations[info.max_reserve.load(std::memory_order_relaxed)]++; } + EXPECT_EQ(info.inline_element_size, sizeof(int64_t)); ++end_size; }); @@ -1928,6 +2092,15 @@ TEST(RawHashSamplerTest, Sample) { for (const auto& [_, count] : observed_checksums) { EXPECT_NEAR((100 * count) / static_cast<double>(tables.size()), 0.2, 0.05); } + + EXPECT_EQ(reservations.size(), 10); + for (const auto& [reservation, count] : reservations) { + EXPECT_GE(reservation, 0); + EXPECT_LT(reservation, 100); + + EXPECT_NEAR((100 * count) / static_cast<double>(tables.size()), 0.1, 0.05) + << reservation; + } } #endif // ABSL_INTERNAL_HASHTABLEZ_SAMPLE @@ -1936,7 +2109,7 @@ TEST(RawHashSamplerTest, DoNotSampleCustomAllocators) { SetHashtablezEnabled(true); SetHashtablezSampleParameter(100); - auto& sampler = HashtablezSampler::Global(); + auto& sampler = GlobalHashtablezSampler(); size_t start_size = 0; start_size += sampler.Iterate([&](const HashtablezInfo&) { ++start_size; }); @@ -1978,6 +2151,36 @@ TEST(Sanitizer, PoisoningOnErase) { } #endif // ABSL_HAVE_ADDRESS_SANITIZER +TEST(Table, AlignOne) { + // We previously had a bug in which we were copying a control byte over the + // first slot when alignof(value_type) is 1. We test repeated + // insertions/erases and verify that the behavior is correct. + Uint8Table t; + std::unordered_set<uint8_t> verifier; // NOLINT + + // Do repeated insertions/erases from the table. + for (int64_t i = 0; i < 100000; ++i) { + SCOPED_TRACE(i); + const uint8_t u = (i * -i) & 0xFF; + auto it = t.find(u); + auto verifier_it = verifier.find(u); + if (it == t.end()) { + ASSERT_EQ(verifier_it, verifier.end()); + t.insert(u); + verifier.insert(u); + } else { + ASSERT_NE(verifier_it, verifier.end()); + t.erase(it); + verifier.erase(verifier_it); + } + } + + EXPECT_EQ(t.size(), verifier.size()); + for (uint8_t u : t) { + EXPECT_EQ(verifier.count(u), 1); + } +} + } // namespace } // namespace container_internal ABSL_NAMESPACE_END diff --git a/absl/container/internal/unordered_map_constructor_test.h b/absl/container/internal/unordered_map_constructor_test.h index 3f90ad7c..7e84dc25 100644 --- a/absl/container/internal/unordered_map_constructor_test.h +++ b/absl/container/internal/unordered_map_constructor_test.h @@ -179,7 +179,7 @@ TYPED_TEST_P(ConstructorTest, InputIteratorBucketHashEqualAlloc) { A alloc(0); std::vector<T> values; std::generate_n(std::back_inserter(values), 10, - hash_internal::Generator<T>()); + hash_internal::UniqueGenerator<T>()); TypeParam m(values.begin(), values.end(), 123, hasher, equal, alloc); EXPECT_EQ(m.hash_function(), hasher); EXPECT_EQ(m.key_eq(), equal); @@ -198,7 +198,7 @@ void InputIteratorBucketAllocTest(std::true_type) { A alloc(0); std::vector<T> values; std::generate_n(std::back_inserter(values), 10, - hash_internal::Generator<T>()); + hash_internal::UniqueGenerator<T>()); TypeParam m(values.begin(), values.end(), 123, alloc); EXPECT_EQ(m.get_allocator(), alloc); EXPECT_THAT(items(m), ::testing::UnorderedElementsAreArray(values)); @@ -221,7 +221,7 @@ void InputIteratorBucketHashAllocTest(std::true_type) { A alloc(0); std::vector<T> values; std::generate_n(std::back_inserter(values), 10, - hash_internal::Generator<T>()); + hash_internal::UniqueGenerator<T>()); TypeParam m(values.begin(), values.end(), 123, hasher, alloc); EXPECT_EQ(m.hash_function(), hasher); EXPECT_EQ(m.get_allocator(), alloc); @@ -241,8 +241,9 @@ TYPED_TEST_P(ConstructorTest, CopyConstructor) { H hasher; E equal; A alloc(0); + hash_internal::UniqueGenerator<T> gen; TypeParam m(123, hasher, equal, alloc); - for (size_t i = 0; i != 10; ++i) m.insert(hash_internal::Generator<T>()()); + for (size_t i = 0; i != 10; ++i) m.insert(gen()); TypeParam n(m); EXPECT_EQ(m.hash_function(), n.hash_function()); EXPECT_EQ(m.key_eq(), n.key_eq()); @@ -262,8 +263,9 @@ void CopyConstructorAllocTest(std::true_type) { H hasher; E equal; A alloc(0); + hash_internal::UniqueGenerator<T> gen; TypeParam m(123, hasher, equal, alloc); - for (size_t i = 0; i != 10; ++i) m.insert(hash_internal::Generator<T>()()); + for (size_t i = 0; i != 10; ++i) m.insert(gen()); TypeParam n(m, A(11)); EXPECT_EQ(m.hash_function(), n.hash_function()); EXPECT_EQ(m.key_eq(), n.key_eq()); @@ -285,8 +287,9 @@ TYPED_TEST_P(ConstructorTest, MoveConstructor) { H hasher; E equal; A alloc(0); + hash_internal::UniqueGenerator<T> gen; TypeParam m(123, hasher, equal, alloc); - for (size_t i = 0; i != 10; ++i) m.insert(hash_internal::Generator<T>()()); + for (size_t i = 0; i != 10; ++i) m.insert(gen()); TypeParam t(m); TypeParam n(std::move(t)); EXPECT_EQ(m.hash_function(), n.hash_function()); @@ -307,8 +310,9 @@ void MoveConstructorAllocTest(std::true_type) { H hasher; E equal; A alloc(0); + hash_internal::UniqueGenerator<T> gen; TypeParam m(123, hasher, equal, alloc); - for (size_t i = 0; i != 10; ++i) m.insert(hash_internal::Generator<T>()()); + for (size_t i = 0; i != 10; ++i) m.insert(gen()); TypeParam t(m); TypeParam n(std::move(t), A(1)); EXPECT_EQ(m.hash_function(), n.hash_function()); @@ -325,7 +329,7 @@ TYPED_TEST_P(ConstructorTest, MoveConstructorAlloc) { TYPED_TEST_P(ConstructorTest, InitializerListBucketHashEqualAlloc) { using T = hash_internal::GeneratedType<TypeParam>; - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()}; using H = typename TypeParam::hasher; using E = typename TypeParam::key_equal; @@ -348,7 +352,7 @@ template <typename TypeParam> void InitializerListBucketAllocTest(std::true_type) { using T = hash_internal::GeneratedType<TypeParam>; using A = typename TypeParam::allocator_type; - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()}; A alloc(0); TypeParam m(values, 123, alloc); @@ -371,7 +375,7 @@ void InitializerListBucketHashAllocTest(std::true_type) { using A = typename TypeParam::allocator_type; H hasher; A alloc(0); - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()}; TypeParam m(values, 123, hasher, alloc); EXPECT_EQ(m.hash_function(), hasher); @@ -392,7 +396,7 @@ TYPED_TEST_P(ConstructorTest, Assignment) { H hasher; E equal; A alloc(0); - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; TypeParam m({gen(), gen(), gen()}, 123, hasher, equal, alloc); TypeParam n; n = m; @@ -412,7 +416,7 @@ TYPED_TEST_P(ConstructorTest, MoveAssignment) { H hasher; E equal; A alloc(0); - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; TypeParam m({gen(), gen(), gen()}, 123, hasher, equal, alloc); TypeParam t(m); TypeParam n; @@ -424,7 +428,7 @@ TYPED_TEST_P(ConstructorTest, MoveAssignment) { TYPED_TEST_P(ConstructorTest, AssignmentFromInitializerList) { using T = hash_internal::GeneratedType<TypeParam>; - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()}; TypeParam m; m = values; @@ -433,7 +437,7 @@ TYPED_TEST_P(ConstructorTest, AssignmentFromInitializerList) { TYPED_TEST_P(ConstructorTest, AssignmentOverwritesExisting) { using T = hash_internal::GeneratedType<TypeParam>; - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; TypeParam m({gen(), gen(), gen()}); TypeParam n({gen()}); n = m; @@ -442,7 +446,7 @@ TYPED_TEST_P(ConstructorTest, AssignmentOverwritesExisting) { TYPED_TEST_P(ConstructorTest, MoveAssignmentOverwritesExisting) { using T = hash_internal::GeneratedType<TypeParam>; - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; TypeParam m({gen(), gen(), gen()}); TypeParam t(m); TypeParam n({gen()}); @@ -452,7 +456,7 @@ TYPED_TEST_P(ConstructorTest, MoveAssignmentOverwritesExisting) { TYPED_TEST_P(ConstructorTest, AssignmentFromInitializerListOverwritesExisting) { using T = hash_internal::GeneratedType<TypeParam>; - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()}; TypeParam m; m = values; @@ -461,7 +465,7 @@ TYPED_TEST_P(ConstructorTest, AssignmentFromInitializerListOverwritesExisting) { TYPED_TEST_P(ConstructorTest, AssignmentOnSelf) { using T = hash_internal::GeneratedType<TypeParam>; - hash_internal::Generator<T> gen; + hash_internal::UniqueGenerator<T> gen; std::initializer_list<T> values = {gen(), gen(), gen(), gen(), gen()}; TypeParam m(values); m = *&m; // Avoid -Wself-assign @@ -472,7 +476,7 @@ TYPED_TEST_P(ConstructorTest, AssignmentOnSelf) { // containers in unspecified state (and in practice in causes memory-leak // according to heap-checker!). -REGISTER_TYPED_TEST_CASE_P( +REGISTER_TYPED_TEST_SUITE_P( ConstructorTest, NoArgs, BucketCount, BucketCountHash, BucketCountHashEqual, BucketCountHashEqualAlloc, BucketCountAlloc, BucketCountHashAlloc, Alloc, InputIteratorBucketHashEqualAlloc, InputIteratorBucketAlloc, diff --git a/absl/container/internal/unordered_map_lookup_test.h b/absl/container/internal/unordered_map_lookup_test.h index e76421e5..3713cd9a 100644 --- a/absl/container/internal/unordered_map_lookup_test.h +++ b/absl/container/internal/unordered_map_lookup_test.h @@ -107,8 +107,8 @@ TYPED_TEST_P(LookupTest, EqualRange) { } } -REGISTER_TYPED_TEST_CASE_P(LookupTest, At, OperatorBracket, Count, Find, - EqualRange); +REGISTER_TYPED_TEST_SUITE_P(LookupTest, At, OperatorBracket, Count, Find, + EqualRange); } // namespace container_internal ABSL_NAMESPACE_END diff --git a/absl/container/internal/unordered_map_modifiers_test.h b/absl/container/internal/unordered_map_modifiers_test.h index 8c9ca779..4d9ab30f 100644 --- a/absl/container/internal/unordered_map_modifiers_test.h +++ b/absl/container/internal/unordered_map_modifiers_test.h @@ -81,6 +81,38 @@ TYPED_TEST_P(ModifiersTest, InsertRange) { ASSERT_THAT(items(m), ::testing::UnorderedElementsAreArray(values)); } +TYPED_TEST_P(ModifiersTest, InsertWithinCapacity) { + using T = hash_internal::GeneratedType<TypeParam>; + using V = typename TypeParam::mapped_type; + T val = hash_internal::Generator<T>()(); + TypeParam m; + m.reserve(10); + const size_t original_capacity = m.bucket_count(); + m.insert(val); + EXPECT_EQ(m.bucket_count(), original_capacity); + T val2 = {val.first, hash_internal::Generator<V>()()}; + m.insert(val2); + EXPECT_EQ(m.bucket_count(), original_capacity); +} + +TYPED_TEST_P(ModifiersTest, InsertRangeWithinCapacity) { +#if !defined(__GLIBCXX__) + using T = hash_internal::GeneratedType<TypeParam>; + std::vector<T> base_values; + std::generate_n(std::back_inserter(base_values), 10, + hash_internal::Generator<T>()); + std::vector<T> values; + while (values.size() != 100) { + std::copy_n(base_values.begin(), 10, std::back_inserter(values)); + } + TypeParam m; + m.reserve(10); + const size_t original_capacity = m.bucket_count(); + m.insert(values.begin(), values.end()); + EXPECT_EQ(m.bucket_count(), original_capacity); +#endif +} + TYPED_TEST_P(ModifiersTest, InsertOrAssign) { #ifdef UNORDERED_MAP_CXX17 using std::get; @@ -265,10 +297,12 @@ TYPED_TEST_P(ModifiersTest, Swap) { // TODO(alkis): Write tests for extract. // TODO(alkis): Write tests for merge. -REGISTER_TYPED_TEST_CASE_P(ModifiersTest, Clear, Insert, InsertHint, - InsertRange, InsertOrAssign, InsertOrAssignHint, - Emplace, EmplaceHint, TryEmplace, TryEmplaceHint, - Erase, EraseRange, EraseKey, Swap); +REGISTER_TYPED_TEST_SUITE_P(ModifiersTest, Clear, Insert, InsertHint, + InsertRange, InsertWithinCapacity, + InsertRangeWithinCapacity, InsertOrAssign, + InsertOrAssignHint, Emplace, EmplaceHint, + TryEmplace, TryEmplaceHint, Erase, EraseRange, + EraseKey, Swap); template <typename Type> struct is_unique_ptr : std::false_type {}; diff --git a/absl/container/internal/unordered_set_constructor_test.h b/absl/container/internal/unordered_set_constructor_test.h index 41165b05..af1116e6 100644 --- a/absl/container/internal/unordered_set_constructor_test.h +++ b/absl/container/internal/unordered_set_constructor_test.h @@ -478,7 +478,7 @@ TYPED_TEST_P(ConstructorTest, AssignmentOnSelf) { EXPECT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values)); } -REGISTER_TYPED_TEST_CASE_P( +REGISTER_TYPED_TEST_SUITE_P( ConstructorTest, NoArgs, BucketCount, BucketCountHash, BucketCountHashEqual, BucketCountHashEqualAlloc, BucketCountAlloc, BucketCountHashAlloc, Alloc, InputIteratorBucketHashEqualAlloc, InputIteratorBucketAlloc, diff --git a/absl/container/internal/unordered_set_lookup_test.h b/absl/container/internal/unordered_set_lookup_test.h index 8f2f4b20..b35f766e 100644 --- a/absl/container/internal/unordered_set_lookup_test.h +++ b/absl/container/internal/unordered_set_lookup_test.h @@ -82,7 +82,7 @@ TYPED_TEST_P(LookupTest, EqualRange) { } } -REGISTER_TYPED_TEST_CASE_P(LookupTest, Count, Find, EqualRange); +REGISTER_TYPED_TEST_SUITE_P(LookupTest, Count, Find, EqualRange); } // namespace container_internal ABSL_NAMESPACE_END diff --git a/absl/container/internal/unordered_set_modifiers_test.h b/absl/container/internal/unordered_set_modifiers_test.h index 26be58d9..d8864bb2 100644 --- a/absl/container/internal/unordered_set_modifiers_test.h +++ b/absl/container/internal/unordered_set_modifiers_test.h @@ -74,6 +74,36 @@ TYPED_TEST_P(ModifiersTest, InsertRange) { ASSERT_THAT(keys(m), ::testing::UnorderedElementsAreArray(values)); } +TYPED_TEST_P(ModifiersTest, InsertWithinCapacity) { + using T = hash_internal::GeneratedType<TypeParam>; + T val = hash_internal::Generator<T>()(); + TypeParam m; + m.reserve(10); + const size_t original_capacity = m.bucket_count(); + m.insert(val); + EXPECT_EQ(m.bucket_count(), original_capacity); + m.insert(val); + EXPECT_EQ(m.bucket_count(), original_capacity); +} + +TYPED_TEST_P(ModifiersTest, InsertRangeWithinCapacity) { +#if !defined(__GLIBCXX__) + using T = hash_internal::GeneratedType<TypeParam>; + std::vector<T> base_values; + std::generate_n(std::back_inserter(base_values), 10, + hash_internal::Generator<T>()); + std::vector<T> values; + while (values.size() != 100) { + values.insert(values.end(), base_values.begin(), base_values.end()); + } + TypeParam m; + m.reserve(10); + const size_t original_capacity = m.bucket_count(); + m.insert(values.begin(), values.end()); + EXPECT_EQ(m.bucket_count(), original_capacity); +#endif +} + TYPED_TEST_P(ModifiersTest, Emplace) { using T = hash_internal::GeneratedType<TypeParam>; T val = hash_internal::Generator<T>()(); @@ -179,9 +209,10 @@ TYPED_TEST_P(ModifiersTest, Swap) { // TODO(alkis): Write tests for extract. // TODO(alkis): Write tests for merge. -REGISTER_TYPED_TEST_CASE_P(ModifiersTest, Clear, Insert, InsertHint, - InsertRange, Emplace, EmplaceHint, Erase, EraseRange, - EraseKey, Swap); +REGISTER_TYPED_TEST_SUITE_P(ModifiersTest, Clear, Insert, InsertHint, + InsertRange, InsertWithinCapacity, + InsertRangeWithinCapacity, Emplace, EmplaceHint, + Erase, EraseRange, EraseKey, Swap); } // namespace container_internal ABSL_NAMESPACE_END |