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Diffstat (limited to 'include/robin_hood.h')
| -rw-r--r-- | include/robin_hood.h | 2544 |
1 files changed, 0 insertions, 2544 deletions
diff --git a/include/robin_hood.h b/include/robin_hood.h deleted file mode 100644 index 0af031f..0000000 --- a/include/robin_hood.h +++ /dev/null @@ -1,2544 +0,0 @@ -// ______ _____ ______ _________ -// ______________ ___ /_ ___(_)_______ ___ /_ ______ ______ ______ / -// __ ___/_ __ \__ __ \__ / __ __ \ __ __ \_ __ \_ __ \_ __ / -// _ / / /_/ /_ /_/ /_ / _ / / / _ / / // /_/ // /_/ // /_/ / -// /_/ \____/ /_.___/ /_/ /_/ /_/ ________/_/ /_/ \____/ \____/ \__,_/ -// _/_____/ -// -// Fast & memory efficient hashtable based on robin hood hashing for C++11/14/17/20 -// https://github.com/martinus/robin-hood-hashing -// -// Licensed under the MIT License <http://opensource.org/licenses/MIT>. -// SPDX-License-Identifier: MIT -// Copyright (c) 2018-2021 Martin Ankerl <http://martin.ankerl.com> -// -// Permission is hereby granted, free of charge, to any person obtaining a copy -// of this software and associated documentation files (the "Software"), to deal -// in the Software without restriction, including without limitation the rights -// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell -// copies of the Software, and to permit persons to whom the Software is -// furnished to do so, subject to the following conditions: -// -// The above copyright notice and this permission notice shall be included in all -// copies or substantial portions of the Software. -// -// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER -// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, -// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE -// SOFTWARE. - -#ifndef ROBIN_HOOD_H_INCLUDED -#define ROBIN_HOOD_H_INCLUDED - -// see https://semver.org/ -#define ROBIN_HOOD_VERSION_MAJOR 3 // for incompatible API changes -#define ROBIN_HOOD_VERSION_MINOR 11 // for adding functionality in a backwards-compatible manner -#define ROBIN_HOOD_VERSION_PATCH 5 // for backwards-compatible bug fixes - -#include <algorithm> -#include <cstdlib> -#include <cstring> -#include <functional> -#include <limits> -#include <memory> // only to support hash of smart pointers -#include <stdexcept> -#include <string> -#include <type_traits> -#include <utility> -#if __cplusplus >= 201703L -# include <string_view> -#endif - -// #define ROBIN_HOOD_LOG_ENABLED -#ifdef ROBIN_HOOD_LOG_ENABLED -# include <iostream> -# define ROBIN_HOOD_LOG(...) \ - std::cout << __FUNCTION__ << "@" << __LINE__ << ": " << __VA_ARGS__ << std::endl; -#else -# define ROBIN_HOOD_LOG(x) -#endif - -// #define ROBIN_HOOD_TRACE_ENABLED -#ifdef ROBIN_HOOD_TRACE_ENABLED -# include <iostream> -# define ROBIN_HOOD_TRACE(...) \ - std::cout << __FUNCTION__ << "@" << __LINE__ << ": " << __VA_ARGS__ << std::endl; -#else -# define ROBIN_HOOD_TRACE(x) -#endif - -// #define ROBIN_HOOD_COUNT_ENABLED -#ifdef ROBIN_HOOD_COUNT_ENABLED -# include <iostream> -# define ROBIN_HOOD_COUNT(x) ++counts().x; -namespace robin_hood { -struct Counts { - uint64_t shiftUp{}; - uint64_t shiftDown{}; -}; -inline std::ostream& operator<<(std::ostream& os, Counts const& c) { - return os << c.shiftUp << " shiftUp" << std::endl << c.shiftDown << " shiftDown" << std::endl; -} - -static Counts& counts() { - static Counts counts{}; - return counts; -} -} // namespace robin_hood -#else -# define ROBIN_HOOD_COUNT(x) -#endif - -// all non-argument macros should use this facility. See -// https://www.fluentcpp.com/2019/05/28/better-macros-better-flags/ -#define ROBIN_HOOD(x) ROBIN_HOOD_PRIVATE_DEFINITION_##x() - -// mark unused members with this macro -#define ROBIN_HOOD_UNUSED(identifier) - -// bitness -#if SIZE_MAX == UINT32_MAX -# define ROBIN_HOOD_PRIVATE_DEFINITION_BITNESS() 32 -#elif SIZE_MAX == UINT64_MAX -# define ROBIN_HOOD_PRIVATE_DEFINITION_BITNESS() 64 -#else -# error Unsupported bitness -#endif - -// endianess -#ifdef _MSC_VER -# define ROBIN_HOOD_PRIVATE_DEFINITION_LITTLE_ENDIAN() 1 -# define ROBIN_HOOD_PRIVATE_DEFINITION_BIG_ENDIAN() 0 -#else -# define ROBIN_HOOD_PRIVATE_DEFINITION_LITTLE_ENDIAN() \ - (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) -# define ROBIN_HOOD_PRIVATE_DEFINITION_BIG_ENDIAN() (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__) -#endif - -// inline -#ifdef _MSC_VER -# define ROBIN_HOOD_PRIVATE_DEFINITION_NOINLINE() __declspec(noinline) -#else -# define ROBIN_HOOD_PRIVATE_DEFINITION_NOINLINE() __attribute__((noinline)) -#endif - -// exceptions -#if !defined(__cpp_exceptions) && !defined(__EXCEPTIONS) && !defined(_CPPUNWIND) -# define ROBIN_HOOD_PRIVATE_DEFINITION_HAS_EXCEPTIONS() 0 -#else -# define ROBIN_HOOD_PRIVATE_DEFINITION_HAS_EXCEPTIONS() 1 -#endif - -// count leading/trailing bits -#if !defined(ROBIN_HOOD_DISABLE_INTRINSICS) -# ifdef _MSC_VER -# if ROBIN_HOOD(BITNESS) == 32 -# define ROBIN_HOOD_PRIVATE_DEFINITION_BITSCANFORWARD() _BitScanForward -# else -# define ROBIN_HOOD_PRIVATE_DEFINITION_BITSCANFORWARD() _BitScanForward64 -# endif -# include <intrin.h> -# pragma intrinsic(ROBIN_HOOD(BITSCANFORWARD)) -# define ROBIN_HOOD_COUNT_TRAILING_ZEROES(x) \ - [](size_t mask) noexcept -> int { \ - unsigned long index; \ - return ROBIN_HOOD(BITSCANFORWARD)(&index, mask) ? static_cast<int>(index) \ - : ROBIN_HOOD(BITNESS); \ - }(x) -# else -# if ROBIN_HOOD(BITNESS) == 32 -# define ROBIN_HOOD_PRIVATE_DEFINITION_CTZ() __builtin_ctzl -# define ROBIN_HOOD_PRIVATE_DEFINITION_CLZ() __builtin_clzl -# else -# define ROBIN_HOOD_PRIVATE_DEFINITION_CTZ() __builtin_ctzll -# define ROBIN_HOOD_PRIVATE_DEFINITION_CLZ() __builtin_clzll -# endif -# define ROBIN_HOOD_COUNT_LEADING_ZEROES(x) ((x) ? ROBIN_HOOD(CLZ)(x) : ROBIN_HOOD(BITNESS)) -# define ROBIN_HOOD_COUNT_TRAILING_ZEROES(x) ((x) ? ROBIN_HOOD(CTZ)(x) : ROBIN_HOOD(BITNESS)) -# endif -#endif - -// fallthrough -#ifndef __has_cpp_attribute // For backwards compatibility -# define __has_cpp_attribute(x) 0 -#endif -#if __has_cpp_attribute(clang::fallthrough) -# define ROBIN_HOOD_PRIVATE_DEFINITION_FALLTHROUGH() [[clang::fallthrough]] -#elif __has_cpp_attribute(gnu::fallthrough) -# define ROBIN_HOOD_PRIVATE_DEFINITION_FALLTHROUGH() [[gnu::fallthrough]] -#else -# define ROBIN_HOOD_PRIVATE_DEFINITION_FALLTHROUGH() -#endif - -// likely/unlikely -#ifdef _MSC_VER -# define ROBIN_HOOD_LIKELY(condition) condition -# define ROBIN_HOOD_UNLIKELY(condition) condition -#else -# define ROBIN_HOOD_LIKELY(condition) __builtin_expect(condition, 1) -# define ROBIN_HOOD_UNLIKELY(condition) __builtin_expect(condition, 0) -#endif - -// detect if native wchar_t type is availiable in MSVC -#ifdef _MSC_VER -# ifdef _NATIVE_WCHAR_T_DEFINED -# define ROBIN_HOOD_PRIVATE_DEFINITION_HAS_NATIVE_WCHART() 1 -# else -# define ROBIN_HOOD_PRIVATE_DEFINITION_HAS_NATIVE_WCHART() 0 -# endif -#else -# define ROBIN_HOOD_PRIVATE_DEFINITION_HAS_NATIVE_WCHART() 1 -#endif - -// detect if MSVC supports the pair(std::piecewise_construct_t,...) consructor being constexpr -#ifdef _MSC_VER -# if _MSC_VER <= 1900 -# define ROBIN_HOOD_PRIVATE_DEFINITION_BROKEN_CONSTEXPR() 1 -# else -# define ROBIN_HOOD_PRIVATE_DEFINITION_BROKEN_CONSTEXPR() 0 -# endif -#else -# define ROBIN_HOOD_PRIVATE_DEFINITION_BROKEN_CONSTEXPR() 0 -#endif - -// workaround missing "is_trivially_copyable" in g++ < 5.0 -// See https://stackoverflow.com/a/31798726/48181 -#if defined(__GNUC__) && __GNUC__ < 5 -# define ROBIN_HOOD_IS_TRIVIALLY_COPYABLE(...) __has_trivial_copy(__VA_ARGS__) -#else -# define ROBIN_HOOD_IS_TRIVIALLY_COPYABLE(...) std::is_trivially_copyable<__VA_ARGS__>::value -#endif - -// helpers for C++ versions, see https://gcc.gnu.org/onlinedocs/cpp/Standard-Predefined-Macros.html -#define ROBIN_HOOD_PRIVATE_DEFINITION_CXX() __cplusplus -#define ROBIN_HOOD_PRIVATE_DEFINITION_CXX98() 199711L -#define ROBIN_HOOD_PRIVATE_DEFINITION_CXX11() 201103L -#define ROBIN_HOOD_PRIVATE_DEFINITION_CXX14() 201402L -#define ROBIN_HOOD_PRIVATE_DEFINITION_CXX17() 201703L - -#if ROBIN_HOOD(CXX) >= ROBIN_HOOD(CXX17) -# define ROBIN_HOOD_PRIVATE_DEFINITION_NODISCARD() [[nodiscard]] -#else -# define ROBIN_HOOD_PRIVATE_DEFINITION_NODISCARD() -#endif - -namespace robin_hood { - -#if ROBIN_HOOD(CXX) >= ROBIN_HOOD(CXX14) -# define ROBIN_HOOD_STD std -#else - -// c++11 compatibility layer -namespace ROBIN_HOOD_STD { -template <class T> -struct alignment_of - : std::integral_constant<std::size_t, alignof(typename std::remove_all_extents<T>::type)> {}; - -template <class T, T... Ints> -class integer_sequence { -public: - using value_type = T; - static_assert(std::is_integral<value_type>::value, "not integral type"); - static constexpr std::size_t size() noexcept { - return sizeof...(Ints); - } -}; -template <std::size_t... Inds> -using index_sequence = integer_sequence<std::size_t, Inds...>; - -namespace detail_ { -template <class T, T Begin, T End, bool> -struct IntSeqImpl { - using TValue = T; - static_assert(std::is_integral<TValue>::value, "not integral type"); - static_assert(Begin >= 0 && Begin < End, "unexpected argument (Begin<0 || Begin<=End)"); - - template <class, class> - struct IntSeqCombiner; - - template <TValue... Inds0, TValue... Inds1> - struct IntSeqCombiner<integer_sequence<TValue, Inds0...>, integer_sequence<TValue, Inds1...>> { - using TResult = integer_sequence<TValue, Inds0..., Inds1...>; - }; - - using TResult = - typename IntSeqCombiner<typename IntSeqImpl<TValue, Begin, Begin + (End - Begin) / 2, - (End - Begin) / 2 == 1>::TResult, - typename IntSeqImpl<TValue, Begin + (End - Begin) / 2, End, - (End - Begin + 1) / 2 == 1>::TResult>::TResult; -}; - -template <class T, T Begin> -struct IntSeqImpl<T, Begin, Begin, false> { - using TValue = T; - static_assert(std::is_integral<TValue>::value, "not integral type"); - static_assert(Begin >= 0, "unexpected argument (Begin<0)"); - using TResult = integer_sequence<TValue>; -}; - -template <class T, T Begin, T End> -struct IntSeqImpl<T, Begin, End, true> { - using TValue = T; - static_assert(std::is_integral<TValue>::value, "not integral type"); - static_assert(Begin >= 0, "unexpected argument (Begin<0)"); - using TResult = integer_sequence<TValue, Begin>; -}; -} // namespace detail_ - -template <class T, T N> -using make_integer_sequence = typename detail_::IntSeqImpl<T, 0, N, (N - 0) == 1>::TResult; - -template <std::size_t N> -using make_index_sequence = make_integer_sequence<std::size_t, N>; - -template <class... T> -using index_sequence_for = make_index_sequence<sizeof...(T)>; - -} // namespace ROBIN_HOOD_STD - -#endif - -namespace detail { - -// make sure we static_cast to the correct type for hash_int -#if ROBIN_HOOD(BITNESS) == 64 -using SizeT = uint64_t; -#else -using SizeT = uint32_t; -#endif - -template <typename T> -T rotr(T x, unsigned k) { - return (x >> k) | (x << (8U * sizeof(T) - k)); -} - -// This cast gets rid of warnings like "cast from 'uint8_t*' {aka 'unsigned char*'} to -// 'uint64_t*' {aka 'long unsigned int*'} increases required alignment of target type". Use with -// care! -template <typename T> -inline T reinterpret_cast_no_cast_align_warning(void* ptr) noexcept { - return reinterpret_cast<T>(ptr); -} - -template <typename T> -inline T reinterpret_cast_no_cast_align_warning(void const* ptr) noexcept { - return reinterpret_cast<T>(ptr); -} - -// make sure this is not inlined as it is slow and dramatically enlarges code, thus making other -// inlinings more difficult. Throws are also generally the slow path. -template <typename E, typename... Args> -[[noreturn]] ROBIN_HOOD(NOINLINE) -#if ROBIN_HOOD(HAS_EXCEPTIONS) - void doThrow(Args&&... args) { - // NOLINTNEXTLINE(cppcoreguidelines-pro-bounds-array-to-pointer-decay) - throw E(std::forward<Args>(args)...); -} -#else - void doThrow(Args&&... ROBIN_HOOD_UNUSED(args) /*unused*/) { - abort(); -} -#endif - -template <typename E, typename T, typename... Args> -T* assertNotNull(T* t, Args&&... args) { - if (ROBIN_HOOD_UNLIKELY(nullptr == t)) { - doThrow<E>(std::forward<Args>(args)...); - } - return t; -} - -template <typename T> -inline T unaligned_load(void const* ptr) noexcept { - // using memcpy so we don't get into unaligned load problems. - // compiler should optimize this very well anyways. - T t; - std::memcpy(&t, ptr, sizeof(T)); - return t; -} - -// Allocates bulks of memory for objects of type T. This deallocates the memory in the destructor, -// and keeps a linked list of the allocated memory around. Overhead per allocation is the size of a -// pointer. -template <typename T, size_t MinNumAllocs = 4, size_t MaxNumAllocs = 256> -class BulkPoolAllocator { -public: - BulkPoolAllocator() noexcept = default; - - // does not copy anything, just creates a new allocator. - BulkPoolAllocator(const BulkPoolAllocator& ROBIN_HOOD_UNUSED(o) /*unused*/) noexcept - : mHead(nullptr) - , mListForFree(nullptr) {} - - BulkPoolAllocator(BulkPoolAllocator&& o) noexcept - : mHead(o.mHead) - , mListForFree(o.mListForFree) { - o.mListForFree = nullptr; - o.mHead = nullptr; - } - - BulkPoolAllocator& operator=(BulkPoolAllocator&& o) noexcept { - reset(); - mHead = o.mHead; - mListForFree = o.mListForFree; - o.mListForFree = nullptr; - o.mHead = nullptr; - return *this; - } - - BulkPoolAllocator& - // NOLINTNEXTLINE(bugprone-unhandled-self-assignment,cert-oop54-cpp) - operator=(const BulkPoolAllocator& ROBIN_HOOD_UNUSED(o) /*unused*/) noexcept { - // does not do anything - return *this; - } - - ~BulkPoolAllocator() noexcept { - reset(); - } - - // Deallocates all allocated memory. - void reset() noexcept { - while (mListForFree) { - T* tmp = *mListForFree; - ROBIN_HOOD_LOG("std::free") - std::free(mListForFree); - mListForFree = reinterpret_cast_no_cast_align_warning<T**>(tmp); - } - mHead = nullptr; - } - - // allocates, but does NOT initialize. Use in-place new constructor, e.g. - // T* obj = pool.allocate(); - // ::new (static_cast<void*>(obj)) T(); - T* allocate() { - T* tmp = mHead; - if (!tmp) { - tmp = performAllocation(); - } - - mHead = *reinterpret_cast_no_cast_align_warning<T**>(tmp); - return tmp; - } - - // does not actually deallocate but puts it in store. - // make sure you have already called the destructor! e.g. with - // obj->~T(); - // pool.deallocate(obj); - void deallocate(T* obj) noexcept { - *reinterpret_cast_no_cast_align_warning<T**>(obj) = mHead; - mHead = obj; - } - - // Adds an already allocated block of memory to the allocator. This allocator is from now on - // responsible for freeing the data (with free()). If the provided data is not large enough to - // make use of, it is immediately freed. Otherwise it is reused and freed in the destructor. - void addOrFree(void* ptr, const size_t numBytes) noexcept { - // calculate number of available elements in ptr - if (numBytes < ALIGNMENT + ALIGNED_SIZE) { - // not enough data for at least one element. Free and return. - ROBIN_HOOD_LOG("std::free") - std::free(ptr); - } else { - ROBIN_HOOD_LOG("add to buffer") - add(ptr, numBytes); - } - } - - void swap(BulkPoolAllocator<T, MinNumAllocs, MaxNumAllocs>& other) noexcept { - using std::swap; - swap(mHead, other.mHead); - swap(mListForFree, other.mListForFree); - } - -private: - // iterates the list of allocated memory to calculate how many to alloc next. - // Recalculating this each time saves us a size_t member. - // This ignores the fact that memory blocks might have been added manually with addOrFree. In - // practice, this should not matter much. - ROBIN_HOOD(NODISCARD) size_t calcNumElementsToAlloc() const noexcept { - auto tmp = mListForFree; - size_t numAllocs = MinNumAllocs; - - while (numAllocs * 2 <= MaxNumAllocs && tmp) { - auto x = reinterpret_cast<T***>(tmp); - tmp = *x; - numAllocs *= 2; - } - - return numAllocs; - } - - // WARNING: Underflow if numBytes < ALIGNMENT! This is guarded in addOrFree(). - void add(void* ptr, const size_t numBytes) noexcept { - const size_t numElements = (numBytes - ALIGNMENT) / ALIGNED_SIZE; - - auto data = reinterpret_cast<T**>(ptr); - - // link free list - auto x = reinterpret_cast<T***>(data); - *x = mListForFree; - mListForFree = data; - - // create linked list for newly allocated data - auto* const headT = - reinterpret_cast_no_cast_align_warning<T*>(reinterpret_cast<char*>(ptr) + ALIGNMENT); - - auto* const head = reinterpret_cast<char*>(headT); - - // Visual Studio compiler automatically unrolls this loop, which is pretty cool - for (size_t i = 0; i < numElements; ++i) { - *reinterpret_cast_no_cast_align_warning<char**>(head + i * ALIGNED_SIZE) = - head + (i + 1) * ALIGNED_SIZE; - } - - // last one points to 0 - *reinterpret_cast_no_cast_align_warning<T**>(head + (numElements - 1) * ALIGNED_SIZE) = - mHead; - mHead = headT; - } - - // Called when no memory is available (mHead == 0). - // Don't inline this slow path. - ROBIN_HOOD(NOINLINE) T* performAllocation() { - size_t const numElementsToAlloc = calcNumElementsToAlloc(); - - // alloc new memory: [prev |T, T, ... T] - size_t const bytes = ALIGNMENT + ALIGNED_SIZE * numElementsToAlloc; - ROBIN_HOOD_LOG("std::malloc " << bytes << " = " << ALIGNMENT << " + " << ALIGNED_SIZE - << " * " << numElementsToAlloc) - add(assertNotNull<std::bad_alloc>(std::malloc(bytes)), bytes); - return mHead; - } - - // enforce byte alignment of the T's -#if ROBIN_HOOD(CXX) >= ROBIN_HOOD(CXX14) - static constexpr size_t ALIGNMENT = - (std::max)(std::alignment_of<T>::value, std::alignment_of<T*>::value); -#else - static const size_t ALIGNMENT = - (ROBIN_HOOD_STD::alignment_of<T>::value > ROBIN_HOOD_STD::alignment_of<T*>::value) - ? ROBIN_HOOD_STD::alignment_of<T>::value - : +ROBIN_HOOD_STD::alignment_of<T*>::value; // the + is for walkarround -#endif - - static constexpr size_t ALIGNED_SIZE = ((sizeof(T) - 1) / ALIGNMENT + 1) * ALIGNMENT; - - static_assert(MinNumAllocs >= 1, "MinNumAllocs"); - static_assert(MaxNumAllocs >= MinNumAllocs, "MaxNumAllocs"); - static_assert(ALIGNED_SIZE >= sizeof(T*), "ALIGNED_SIZE"); - static_assert(0 == (ALIGNED_SIZE % sizeof(T*)), "ALIGNED_SIZE mod"); - static_assert(ALIGNMENT >= sizeof(T*), "ALIGNMENT"); - - T* mHead{nullptr}; - T** mListForFree{nullptr}; -}; - -template <typename T, size_t MinSize, size_t MaxSize, bool IsFlat> -struct NodeAllocator; - -// dummy allocator that does nothing -template <typename T, size_t MinSize, size_t MaxSize> -struct NodeAllocator<T, MinSize, MaxSize, true> { - - // we are not using the data, so just free it. - void addOrFree(void* ptr, size_t ROBIN_HOOD_UNUSED(numBytes) /*unused*/) noexcept { - ROBIN_HOOD_LOG("std::free") - std::free(ptr); - } -}; - -template <typename T, size_t MinSize, size_t MaxSize> -struct NodeAllocator<T, MinSize, MaxSize, false> : public BulkPoolAllocator<T, MinSize, MaxSize> {}; - -// c++14 doesn't have is_nothrow_swappable, and clang++ 6.0.1 doesn't like it either, so I'm making -// my own here. -namespace swappable { -#if ROBIN_HOOD(CXX) < ROBIN_HOOD(CXX17) -using std::swap; -template <typename T> -struct nothrow { - static const bool value = noexcept(swap(std::declval<T&>(), std::declval<T&>())); -}; -#else -template <typename T> -struct nothrow { - static const bool value = std::is_nothrow_swappable<T>::value; -}; -#endif -} // namespace swappable - -} // namespace detail - -struct is_transparent_tag {}; - -// A custom pair implementation is used in the map because std::pair is not is_trivially_copyable, -// which means it would not be allowed to be used in std::memcpy. This struct is copyable, which is -// also tested. -template <typename T1, typename T2> -struct pair { - using first_type = T1; - using second_type = T2; - - template <typename U1 = T1, typename U2 = T2, - typename = typename std::enable_if<std::is_default_constructible<U1>::value && - std::is_default_constructible<U2>::value>::type> - constexpr pair() noexcept(noexcept(U1()) && noexcept(U2())) - : first() - , second() {} - - // pair constructors are explicit so we don't accidentally call this ctor when we don't have to. - explicit constexpr pair(std::pair<T1, T2> const& o) noexcept( - noexcept(T1(std::declval<T1 const&>())) && noexcept(T2(std::declval<T2 const&>()))) - : first(o.first) - , second(o.second) {} - - // pair constructors are explicit so we don't accidentally call this ctor when we don't have to. - explicit constexpr pair(std::pair<T1, T2>&& o) noexcept(noexcept( - T1(std::move(std::declval<T1&&>()))) && noexcept(T2(std::move(std::declval<T2&&>())))) - : first(std::move(o.first)) - , second(std::move(o.second)) {} - - constexpr pair(T1&& a, T2&& b) noexcept(noexcept( - T1(std::move(std::declval<T1&&>()))) && noexcept(T2(std::move(std::declval<T2&&>())))) - : first(std::move(a)) - , second(std::move(b)) {} - - template <typename U1, typename U2> - constexpr pair(U1&& a, U2&& b) noexcept(noexcept(T1(std::forward<U1>( - std::declval<U1&&>()))) && noexcept(T2(std::forward<U2>(std::declval<U2&&>())))) - : first(std::forward<U1>(a)) - , second(std::forward<U2>(b)) {} - - template <typename... U1, typename... U2> - // MSVC 2015 produces error "C2476: ‘constexpr’ constructor does not initialize all members" - // if this constructor is constexpr -#if !ROBIN_HOOD(BROKEN_CONSTEXPR) - constexpr -#endif - pair(std::piecewise_construct_t /*unused*/, std::tuple<U1...> a, - std::tuple<U2...> - b) noexcept(noexcept(pair(std::declval<std::tuple<U1...>&>(), - std::declval<std::tuple<U2...>&>(), - ROBIN_HOOD_STD::index_sequence_for<U1...>(), - ROBIN_HOOD_STD::index_sequence_for<U2...>()))) - : pair(a, b, ROBIN_HOOD_STD::index_sequence_for<U1...>(), - ROBIN_HOOD_STD::index_sequence_for<U2...>()) { - } - - // constructor called from the std::piecewise_construct_t ctor - template <typename... U1, size_t... I1, typename... U2, size_t... I2> - pair(std::tuple<U1...>& a, std::tuple<U2...>& b, ROBIN_HOOD_STD::index_sequence<I1...> /*unused*/, ROBIN_HOOD_STD::index_sequence<I2...> /*unused*/) noexcept( - noexcept(T1(std::forward<U1>(std::get<I1>( - std::declval<std::tuple< - U1...>&>()))...)) && noexcept(T2(std:: - forward<U2>(std::get<I2>( - std::declval<std::tuple<U2...>&>()))...))) - : first(std::forward<U1>(std::get<I1>(a))...) - , second(std::forward<U2>(std::get<I2>(b))...) { - // make visual studio compiler happy about warning about unused a & b. - // Visual studio's pair implementation disables warning 4100. - (void)a; - (void)b; - } - - void swap(pair<T1, T2>& o) noexcept((detail::swappable::nothrow<T1>::value) && - (detail::swappable::nothrow<T2>::value)) { - using std::swap; - swap(first, o.first); - swap(second, o.second); - } - - T1 first; // NOLINT(misc-non-private-member-variables-in-classes) - T2 second; // NOLINT(misc-non-private-member-variables-in-classes) -}; - -template <typename A, typename B> -inline void swap(pair<A, B>& a, pair<A, B>& b) noexcept( - noexcept(std::declval<pair<A, B>&>().swap(std::declval<pair<A, B>&>()))) { - a.swap(b); -} - -template <typename A, typename B> -inline constexpr bool operator==(pair<A, B> const& x, pair<A, B> const& y) { - return (x.first == y.first) && (x.second == y.second); -} -template <typename A, typename B> -inline constexpr bool operator!=(pair<A, B> const& x, pair<A, B> const& y) { - return !(x == y); -} -template <typename A, typename B> -inline constexpr bool operator<(pair<A, B> const& x, pair<A, B> const& y) noexcept(noexcept( - std::declval<A const&>() < std::declval<A const&>()) && noexcept(std::declval<B const&>() < - std::declval<B const&>())) { - return x.first < y.first || (!(y.first < x.first) && x.second < y.second); -} -template <typename A, typename B> -inline constexpr bool operator>(pair<A, B> const& x, pair<A, B> const& y) { - return y < x; -} -template <typename A, typename B> -inline constexpr bool operator<=(pair<A, B> const& x, pair<A, B> const& y) { - return !(x > y); -} -template <typename A, typename B> -inline constexpr bool operator>=(pair<A, B> const& x, pair<A, B> const& y) { - return !(x < y); -} - -inline size_t hash_bytes(void const* ptr, size_t len) noexcept { - static constexpr uint64_t m = UINT64_C(0xc6a4a7935bd1e995); - static constexpr uint64_t seed = UINT64_C(0xe17a1465); - static constexpr unsigned int r = 47; - - auto const* const data64 = static_cast<uint64_t const*>(ptr); - uint64_t h = seed ^ (len * m); - - size_t const n_blocks = len / 8; - for (size_t i = 0; i < n_blocks; ++i) { - auto k = detail::unaligned_load<uint64_t>(data64 + i); - - k *= m; - k ^= k >> r; - k *= m; - - h ^= k; - h *= m; - } - - auto const* const data8 = reinterpret_cast<uint8_t const*>(data64 + n_blocks); - switch (len & 7U) { - case 7: - h ^= static_cast<uint64_t>(data8[6]) << 48U; - ROBIN_HOOD(FALLTHROUGH); // FALLTHROUGH - case 6: - h ^= static_cast<uint64_t>(data8[5]) << 40U; - ROBIN_HOOD(FALLTHROUGH); // FALLTHROUGH - case 5: - h ^= static_cast<uint64_t>(data8[4]) << 32U; - ROBIN_HOOD(FALLTHROUGH); // FALLTHROUGH - case 4: - h ^= static_cast<uint64_t>(data8[3]) << 24U; - ROBIN_HOOD(FALLTHROUGH); // FALLTHROUGH - case 3: - h ^= static_cast<uint64_t>(data8[2]) << 16U; - ROBIN_HOOD(FALLTHROUGH); // FALLTHROUGH - case 2: - h ^= static_cast<uint64_t>(data8[1]) << 8U; - ROBIN_HOOD(FALLTHROUGH); // FALLTHROUGH - case 1: - h ^= static_cast<uint64_t>(data8[0]); - h *= m; - ROBIN_HOOD(FALLTHROUGH); // FALLTHROUGH - default: - break; - } - - h ^= h >> r; - - // not doing the final step here, because this will be done by keyToIdx anyways - // h *= m; - // h ^= h >> r; - return static_cast<size_t>(h); -} - -inline size_t hash_int(uint64_t x) noexcept { - // tried lots of different hashes, let's stick with murmurhash3. It's simple, fast, well tested, - // and doesn't need any special 128bit operations. - x ^= x >> 33U; - x *= UINT64_C(0xff51afd7ed558ccd); - x ^= x >> 33U; - - // not doing the final step here, because this will be done by keyToIdx anyways - // x *= UINT64_C(0xc4ceb9fe1a85ec53); - // x ^= x >> 33U; - return static_cast<size_t>(x); -} - -// A thin wrapper around std::hash, performing an additional simple mixing step of the result. -template <typename T, typename Enable = void> -struct hash : public std::hash<T> { - size_t operator()(T const& obj) const - noexcept(noexcept(std::declval<std::hash<T>>().operator()(std::declval<T const&>()))) { - // call base hash - auto result = std::hash<T>::operator()(obj); - // return mixed of that, to be save against identity has - return hash_int(static_cast<detail::SizeT>(result)); - } -}; - -template <typename CharT> -struct hash<std::basic_string<CharT>> { - size_t operator()(std::basic_string<CharT> const& str) const noexcept { - return hash_bytes(str.data(), sizeof(CharT) * str.size()); - } -}; - -#if ROBIN_HOOD(CXX) >= ROBIN_HOOD(CXX17) -template <typename CharT> -struct hash<std::basic_string_view<CharT>> { - size_t operator()(std::basic_string_view<CharT> const& sv) const noexcept { - return hash_bytes(sv.data(), sizeof(CharT) * sv.size()); - } -}; -#endif - -template <class T> -struct hash<T*> { - size_t operator()(T* ptr) const noexcept { - return hash_int(reinterpret_cast<detail::SizeT>(ptr)); - } -}; - -template <class T> -struct hash<std::unique_ptr<T>> { - size_t operator()(std::unique_ptr<T> const& ptr) const noexcept { - return hash_int(reinterpret_cast<detail::SizeT>(ptr.get())); - } -}; - -template <class T> -struct hash<std::shared_ptr<T>> { - size_t operator()(std::shared_ptr<T> const& ptr) const noexcept { - return hash_int(reinterpret_cast<detail::SizeT>(ptr.get())); - } -}; - -template <typename Enum> -struct hash<Enum, typename std::enable_if<std::is_enum<Enum>::value>::type> { - size_t operator()(Enum e) const noexcept { - using Underlying = typename std::underlying_type<Enum>::type; - return hash<Underlying>{}(static_cast<Underlying>(e)); - } -}; - -#define ROBIN_HOOD_HASH_INT(T) \ - template <> \ - struct hash<T> { \ - size_t operator()(T const& obj) const noexcept { \ - return hash_int(static_cast<uint64_t>(obj)); \ - } \ - } - -#if defined(__GNUC__) && !defined(__clang__) -# pragma GCC diagnostic push -# pragma GCC diagnostic ignored "-Wuseless-cast" -#endif -// see https://en.cppreference.com/w/cpp/utility/hash -ROBIN_HOOD_HASH_INT(bool); -ROBIN_HOOD_HASH_INT(char); -ROBIN_HOOD_HASH_INT(signed char); -ROBIN_HOOD_HASH_INT(unsigned char); -ROBIN_HOOD_HASH_INT(char16_t); -ROBIN_HOOD_HASH_INT(char32_t); -#if ROBIN_HOOD(HAS_NATIVE_WCHART) -ROBIN_HOOD_HASH_INT(wchar_t); -#endif -ROBIN_HOOD_HASH_INT(short); -ROBIN_HOOD_HASH_INT(unsigned short); -ROBIN_HOOD_HASH_INT(int); -ROBIN_HOOD_HASH_INT(unsigned int); -ROBIN_HOOD_HASH_INT(long); -ROBIN_HOOD_HASH_INT(long long); -ROBIN_HOOD_HASH_INT(unsigned long); -ROBIN_HOOD_HASH_INT(unsigned long long); -#if defined(__GNUC__) && !defined(__clang__) -# pragma GCC diagnostic pop -#endif -namespace detail { - -template <typename T> -struct void_type { - using type = void; -}; - -template <typename T, typename = void> -struct has_is_transparent : public std::false_type {}; - -template <typename T> -struct has_is_transparent<T, typename void_type<typename T::is_transparent>::type> - : public std::true_type {}; - -// using wrapper classes for hash and key_equal prevents the diamond problem when the same type -// is used. see https://stackoverflow.com/a/28771920/48181 -template <typename T> -struct WrapHash : public T { - WrapHash() = default; - explicit WrapHash(T const& o) noexcept(noexcept(T(std::declval<T const&>()))) - : T(o) {} -}; - -template <typename T> -struct WrapKeyEqual : public T { - WrapKeyEqual() = default; - explicit WrapKeyEqual(T const& o) noexcept(noexcept(T(std::declval<T const&>()))) - : T(o) {} -}; - -// A highly optimized hashmap implementation, using the Robin Hood algorithm. -// -// In most cases, this map should be usable as a drop-in replacement for std::unordered_map, but -// be about 2x faster in most cases and require much less allocations. -// -// This implementation uses the following memory layout: -// -// [Node, Node, ... Node | info, info, ... infoSentinel ] -// -// * Node: either a DataNode that directly has the std::pair<key, val> as member, -// or a DataNode with a pointer to std::pair<key,val>. Which DataNode representation to use -// depends on how fast the swap() operation is. Heuristically, this is automatically choosen -// based on sizeof(). there are always 2^n Nodes. -// -// * info: Each Node in the map has a corresponding info byte, so there are 2^n info bytes. -// Each byte is initialized to 0, meaning the corresponding Node is empty. Set to 1 means the -// corresponding node contains data. Set to 2 means the corresponding Node is filled, but it -// actually belongs to the previous position and was pushed out because that place is already -// taken. -// -// * infoSentinel: Sentinel byte set to 1, so that iterator's ++ can stop at end() without the -// need for a idx variable. -// -// According to STL, order of templates has effect on throughput. That's why I've moved the -// boolean to the front. -// https://www.reddit.com/r/cpp/comments/ahp6iu/compile_time_binary_size_reductions_and_cs_future/eeguck4/ -template <bool IsFlat, size_t MaxLoadFactor100, typename Key, typename T, typename Hash, - typename KeyEqual> -class Table - : public WrapHash<Hash>, - public WrapKeyEqual<KeyEqual>, - detail::NodeAllocator< - typename std::conditional< - std::is_void<T>::value, Key, - robin_hood::pair<typename std::conditional<IsFlat, Key, Key const>::type, T>>::type, - 4, 16384, IsFlat> { -public: - static constexpr bool is_flat = IsFlat; - static constexpr bool is_map = !std::is_void<T>::value; - static constexpr bool is_set = !is_map; - static constexpr bool is_transparent = - has_is_transparent<Hash>::value && has_is_transparent<KeyEqual>::value; - - using key_type = Key; - using mapped_type = T; - using value_type = typename std::conditional< - is_set, Key, - robin_hood::pair<typename std::conditional<is_flat, Key, Key const>::type, T>>::type; - using size_type = size_t; - using hasher = Hash; - using key_equal = KeyEqual; - using Self = Table<IsFlat, MaxLoadFactor100, key_type, mapped_type, hasher, key_equal>; - -private: - static_assert(MaxLoadFactor100 > 10 && MaxLoadFactor100 < 100, - "MaxLoadFactor100 needs to be >10 && < 100"); - - using WHash = WrapHash<Hash>; - using WKeyEqual = WrapKeyEqual<KeyEqual>; - - // configuration defaults - - // make sure we have 8 elements, needed to quickly rehash mInfo - static constexpr size_t InitialNumElements = sizeof(uint64_t); - static constexpr uint32_t InitialInfoNumBits = 5; - static constexpr uint8_t InitialInfoInc = 1U << InitialInfoNumBits; - static constexpr size_t InfoMask = InitialInfoInc - 1U; - static constexpr uint8_t InitialInfoHashShift = 0; - using DataPool = detail::NodeAllocator<value_type, 4, 16384, IsFlat>; - - // type needs to be wider than uint8_t. - using InfoType = uint32_t; - - // DataNode //////////////////////////////////////////////////////// - - // Primary template for the data node. We have special implementations for small and big - // objects. For large objects it is assumed that swap() is fairly slow, so we allocate these - // on the heap so swap merely swaps a pointer. - template <typename M, bool> - class DataNode { |