From 48cd2c3f351ff188bc85684b84a91b6e6d17d896 Mon Sep 17 00:00:00 2001 From: Abseil Team Date: Thu, 27 Sep 2018 12:24:54 -0700 Subject: Export of internal Abseil changes. -- 4eacae3ff1b14b1d309e8092185bc10e8a6203cf by Derek Mauro : Release SwissTable - a fast, efficient, cache-friendly hash table. https://www.youtube.com/watch?v=ncHmEUmJZf4 PiperOrigin-RevId: 214816527 -- df8c3dfab3cfb2f4365909a84d0683b193cfbb11 by Derek Mauro : Internal change PiperOrigin-RevId: 214785288 -- 1eabd5266bbcebc33eecc91e5309b751856a75c8 by Abseil Team : Internal change PiperOrigin-RevId: 214722931 -- 2ebbfac950f83146b46253038e7dd7dcde9f2951 by Derek Mauro : Internal change PiperOrigin-RevId: 214701684 GitOrigin-RevId: 4eacae3ff1b14b1d309e8092185bc10e8a6203cf Change-Id: I9ba64e395b22ad7863213d157b8019b082adc19d --- absl/container/internal/raw_hash_map.h | 182 +++++++++++++++++++++++++++++++++ 1 file changed, 182 insertions(+) create mode 100644 absl/container/internal/raw_hash_map.h (limited to 'absl/container/internal/raw_hash_map.h') diff --git a/absl/container/internal/raw_hash_map.h b/absl/container/internal/raw_hash_map.h new file mode 100644 index 0000000..1edc007 --- /dev/null +++ b/absl/container/internal/raw_hash_map.h @@ -0,0 +1,182 @@ +// Copyright 2018 The Abseil Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#ifndef ABSL_CONTAINER_INTERNAL_RAW_HASH_MAP_H_ +#define ABSL_CONTAINER_INTERNAL_RAW_HASH_MAP_H_ + +#include +#include +#include + +#include "absl/container/internal/container_memory.h" +#include "absl/container/internal/raw_hash_set.h" // IWYU pragma: export + +namespace absl { +namespace container_internal { + +template +class raw_hash_map : public raw_hash_set { + // P is Policy. It's passed as a template argument to support maps that have + // incomplete types as values, as in unordered_map. + // MappedReference<> may be a non-reference type. + template + using MappedReference = decltype(P::value( + std::addressof(std::declval()))); + + // MappedConstReference<> may be a non-reference type. + template + using MappedConstReference = decltype(P::value( + std::addressof(std::declval()))); + + public: + using key_type = typename Policy::key_type; + using mapped_type = typename Policy::mapped_type; + template + using key_arg = typename raw_hash_map::raw_hash_set::template key_arg; + + static_assert(!std::is_reference::value, ""); + // TODO(alkis): remove this assertion and verify that reference mapped_type is + // supported. + static_assert(!std::is_reference::value, ""); + + using iterator = typename raw_hash_map::raw_hash_set::iterator; + using const_iterator = typename raw_hash_map::raw_hash_set::const_iterator; + + raw_hash_map() {} + using raw_hash_map::raw_hash_set::raw_hash_set; + + // The last two template parameters ensure that both arguments are rvalues + // (lvalue arguments are handled by the overloads below). This is necessary + // for supporting bitfield arguments. + // + // union { int n : 1; }; + // flat_hash_map m; + // m.insert_or_assign(n, n); + template + std::pair insert_or_assign(key_arg&& k, V&& v) { + return insert_or_assign_impl(std::forward(k), std::forward(v)); + } + + template + std::pair insert_or_assign(key_arg&& k, const V& v) { + return insert_or_assign_impl(std::forward(k), v); + } + + template + std::pair insert_or_assign(const key_arg& k, V&& v) { + return insert_or_assign_impl(k, std::forward(v)); + } + + template + std::pair insert_or_assign(const key_arg& k, const V& v) { + return insert_or_assign_impl(k, v); + } + + template + iterator insert_or_assign(const_iterator, key_arg&& k, V&& v) { + return insert_or_assign(std::forward(k), std::forward(v)).first; + } + + template + iterator insert_or_assign(const_iterator, key_arg&& k, const V& v) { + return insert_or_assign(std::forward(k), v).first; + } + + template + iterator insert_or_assign(const_iterator, const key_arg& k, V&& v) { + return insert_or_assign(k, std::forward(v)).first; + } + + template + iterator insert_or_assign(const_iterator, const key_arg& k, const V& v) { + return insert_or_assign(k, v).first; + } + + template ::value, int>::type = 0, + K* = nullptr> + std::pair try_emplace(key_arg&& k, Args&&... args) { + return try_emplace_impl(std::forward(k), std::forward(args)...); + } + + template ::value, int>::type = 0> + std::pair try_emplace(const key_arg& k, Args&&... args) { + return try_emplace_impl(k, std::forward(args)...); + } + + template + iterator try_emplace(const_iterator, key_arg&& k, Args&&... args) { + return try_emplace(std::forward(k), std::forward(args)...).first; + } + + template + iterator try_emplace(const_iterator, const key_arg& k, Args&&... args) { + return try_emplace(k, std::forward(args)...).first; + } + + template + MappedReference

at(const key_arg& key) { + auto it = this->find(key); + if (it == this->end()) std::abort(); + return Policy::value(&*it); + } + + template + MappedConstReference

at(const key_arg& key) const { + auto it = this->find(key); + if (it == this->end()) std::abort(); + return Policy::value(&*it); + } + + template + MappedReference

operator[](key_arg&& key) { + return Policy::value(&*try_emplace(std::forward(key)).first); + } + + template + MappedReference

operator[](const key_arg& key) { + return Policy::value(&*try_emplace(key).first); + } + + private: + template + std::pair insert_or_assign_impl(K&& k, V&& v) { + auto res = this->find_or_prepare_insert(k); + if (res.second) + this->emplace_at(res.first, std::forward(k), std::forward(v)); + else + Policy::value(&*this->iterator_at(res.first)) = std::forward(v); + return {this->iterator_at(res.first), res.second}; + } + + template + std::pair try_emplace_impl(K&& k, Args&&... args) { + auto res = this->find_or_prepare_insert(k); + if (res.second) + this->emplace_at(res.first, std::piecewise_construct, + std::forward_as_tuple(std::forward(k)), + std::forward_as_tuple(std::forward(args)...)); + return {this->iterator_at(res.first), res.second}; + } +}; + +} // namespace container_internal +} // namespace absl + +#endif // ABSL_CONTAINER_INTERNAL_RAW_HASH_MAP_H_ -- cgit v1.2.3