168492376
/
gnss-sim
1
0
Fork 0
Code Issues 10 Pull Requests Packages Projects Releases Wiki Activity
gnss-sim/3rdparty/boost/unordered/detail/foa/table.hpp

662 lines
20 KiB
C++
Raw Blame History

/* Fast open-addressing hash table.
*
* Copyright 2022-2024 Joaquin M Lopez Munoz.
* Copyright 2023 Christian Mazakas.
* Copyright 2024 Braden Ganetsky.
* Distributed under the Boost Software License, Version 1.0.
* (See accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
*
* See https://www.boost.org/libs/unordered for library home page.
*/
#ifndef BOOST_UNORDERED_DETAIL_FOA_TABLE_HPP
#define BOOST_UNORDERED_DETAIL_FOA_TABLE_HPP
#include <boost/assert.hpp>
#include <boost/config.hpp>
#include <boost/config/workaround.hpp>
#include <boost/core/serialization.hpp>
#include <boost/unordered/detail/foa/core.hpp>
#include <boost/unordered/detail/serialize_tracked_address.hpp>
#include <boost/unordered/detail/type_traits.hpp>
#include <cstddef>
#include <iterator>
#include <memory>
#include <type_traits>
#include <utility>
namespace boost{
namespace unordered{
namespace detail{
namespace foa{
/* use plain integrals for group metadata storage */
template<typename Integral>
struct plain_integral
{
operator Integral()const{return n;}
void operator=(Integral m){n=m;}
#if BOOST_WORKAROUND(BOOST_GCC,>=50000 && BOOST_GCC<60000)
void operator|=(Integral m){n=static_cast<Integral>(n|m);}
void operator&=(Integral m){n=static_cast<Integral>(n&m);}
#else
void operator|=(Integral m){n|=m;}
void operator&=(Integral m){n&=m;}
#endif
Integral n;
};
struct plain_size_control
{
std::size_t ml;
std::size_t size;
};
template<typename,typename,typename,typename>
class table;
/* table_iterator keeps two pointers:
*
* - A pointer p to the element slot.
* - A pointer pc to the n-th byte of the associated group metadata, where n
* is the position of the element in the group.
*
* A simpler solution would have been to keep a pointer p to the element, a
* pointer pg to the group, and the position n, but that would increase
* sizeof(table_iterator) by 4/8 bytes. In order to make this compact
* representation feasible, it is required that group objects are aligned
* to their size, so that we can recover pg and n as
*
* - n = pc%sizeof(group)
* - pg = pc-n
*
* (for explanatory purposes pg and pc are treated above as if they were memory
* addresses rather than pointers).
*
* p = nullptr is conventionally used to mark end() iterators.
*/
/* internal conversion from const_iterator to iterator */
struct const_iterator_cast_tag{};
template<typename TypePolicy,typename GroupPtr,bool Const>
class table_iterator
{
using group_pointer_traits=boost::pointer_traits<GroupPtr>;
using type_policy=TypePolicy;
using table_element_type=typename type_policy::element_type;
using group_type=typename group_pointer_traits::element_type;
using table_element_pointer=
typename group_pointer_traits::template rebind<table_element_type>;
using char_pointer=
typename group_pointer_traits::template rebind<unsigned char>;
static constexpr auto N=group_type::N;
static constexpr auto regular_layout=group_type::regular_layout;
public:
using difference_type=std::ptrdiff_t;
using value_type=typename type_policy::value_type;
using pointer=
typename std::conditional<Const,value_type const*,value_type*>::type;
using reference=
typename std::conditional<Const,value_type const&,value_type&>::type;
using iterator_category=std::forward_iterator_tag;
using element_type=
typename std::conditional<Const,value_type const,value_type>::type;
table_iterator():pc_{nullptr},p_{nullptr}{};
template<bool Const2,typename std::enable_if<!Const2>::type* =nullptr>
table_iterator(const table_iterator<TypePolicy,GroupPtr,Const2>& x):
pc_{x.pc_},p_{x.p_}{}
table_iterator(
const_iterator_cast_tag, const table_iterator<TypePolicy,GroupPtr,true>& x):
pc_{x.pc_},p_{x.p_}{}
inline reference operator*()const noexcept
{return type_policy::value_from(*p());}
inline pointer operator->()const noexcept
{return std::addressof(type_policy::value_from(*p()));}
inline table_iterator& operator++()noexcept{increment();return *this;}
inline table_iterator operator++(int)noexcept
{auto x=*this;increment();return x;}
friend inline bool operator==(
const table_iterator& x,const table_iterator& y)
{return x.p()==y.p();}
friend inline bool operator!=(
const table_iterator& x,const table_iterator& y)
{return !(x==y);}
private:
template<typename,typename,bool> friend class table_iterator;
template<typename> friend class table_erase_return_type;
template<typename,typename,typename,typename> friend class table;
table_iterator(group_type* pg,std::size_t n,const table_element_type* ptet):
pc_{to_pointer<char_pointer>(
reinterpret_cast<unsigned char*>(const_cast<group_type*>(pg))+n)},
p_{to_pointer<table_element_pointer>(const_cast<table_element_type*>(ptet))}
{}
unsigned char* pc()const noexcept{return boost::to_address(pc_);}
table_element_type* p()const noexcept{return boost::to_address(p_);}
inline void increment()noexcept
{
BOOST_ASSERT(p()!=nullptr);
increment(std::integral_constant<bool,regular_layout>{});
}
inline void increment(std::true_type /* regular layout */)noexcept
{
using diff_type=
typename boost::pointer_traits<char_pointer>::difference_type;
for(;;){
++p_;
if(reinterpret_cast<uintptr_t>(pc())%sizeof(group_type)==N-1){
pc_+=static_cast<diff_type>(sizeof(group_type)-(N-1));
break;
}
++pc_;
if(!group_type::is_occupied(pc()))continue;
if(BOOST_UNLIKELY(group_type::is_sentinel(pc())))p_=nullptr;
return;
}
for(;;){
int mask=reinterpret_cast<group_type*>(pc())->match_occupied();
if(mask!=0){
auto n=unchecked_countr_zero(mask);
if(BOOST_UNLIKELY(reinterpret_cast<group_type*>(pc())->is_sentinel(n))){
p_=nullptr;
}
else{
pc_+=static_cast<diff_type>(n);
p_+=static_cast<diff_type>(n);
}
return;
}
pc_+=static_cast<diff_type>(sizeof(group_type));
p_+=static_cast<diff_type>(N);
}
}
inline void increment(std::false_type /* interleaved */)noexcept
{
using diff_type=
typename boost::pointer_traits<char_pointer>::difference_type;
std::size_t n0=reinterpret_cast<uintptr_t>(pc())%sizeof(group_type);
pc_-=static_cast<diff_type>(n0);
int mask=(
reinterpret_cast<group_type*>(pc())->match_occupied()>>(n0+1))<<(n0+1);
if(!mask){
do{
pc_+=sizeof(group_type);
p_+=N;
}
while((mask=reinterpret_cast<group_type*>(pc())->match_occupied())==0);
}
auto n=unchecked_countr_zero(mask);
if(BOOST_UNLIKELY(reinterpret_cast<group_type*>(pc())->is_sentinel(n))){
p_=nullptr;
}
else{
pc_+=static_cast<diff_type>(n);
p_-=static_cast<diff_type>(n0);
p_+=static_cast<diff_type>(n);
}
}
template<typename Archive>
friend void serialization_track(Archive& ar,const table_iterator& x)
{
if(x.p()){
track_address(ar,x.pc_);
track_address(ar,x.p_);
}
}
friend class boost::serialization::access;
template<typename Archive>
void serialize(Archive& ar,unsigned int)
{
if(!p())pc_=nullptr;
serialize_tracked_address(ar,pc_);
serialize_tracked_address(ar,p_);
}
char_pointer pc_=nullptr;
table_element_pointer p_=nullptr;
};
/* Returned by table::erase([const_]iterator) to avoid iterator increment
* if discarded.
*/
template<typename Iterator>
class table_erase_return_type;
template<typename TypePolicy,typename GroupPtr,bool Const>
class table_erase_return_type<table_iterator<TypePolicy,GroupPtr,Const>>
{
using iterator=table_iterator<TypePolicy,GroupPtr,Const>;
using const_iterator=table_iterator<TypePolicy,GroupPtr,true>;
public:
/* can't delete it because VS in pre-C++17 mode needs to see it for RVO */
table_erase_return_type(const table_erase_return_type&);
operator iterator()const noexcept
{
auto it=pos;
it.increment(); /* valid even if *it was erased */
return iterator(const_iterator_cast_tag{},it);
}
template<
bool dependent_value=false,
typename std::enable_if<!Const||dependent_value>::type* =nullptr
>
operator const_iterator()const noexcept{return this->operator iterator();}
private:
template<typename,typename,typename,typename> friend class table;
table_erase_return_type(const_iterator pos_):pos{pos_}{}
table_erase_return_type& operator=(const table_erase_return_type&)=delete;
const_iterator pos;
};
/* foa::table interface departs in a number of ways from that of C++ unordered
* associative containers because it's not for end-user consumption
* (boost::unordered_(flat|node)_(map|set) wrappers complete it as
* appropriate).
*
* The table supports two main modes of operation: flat and node-based. In the
* flat case, buckets directly store elements. For node-based, buckets store
* pointers to individually heap-allocated elements.
*
* For both flat and node-based:
*
* - begin() is not O(1).
* - No bucket API.
* - Load factor is fixed and can't be set by the user.
*
* For flat only:
*
* - value_type must be moveable.
* - Pointer stability is not kept under rehashing.
* - No extract API.
*
* try_emplace, erase and find support heterogeneous lookup by default,
* that is, without checking for any ::is_transparent typedefs --the
* checking is done by boost::unordered_(flat|node)_(map|set).
*/
template<typename,typename,typename,typename>
class concurrent_table; /* concurrent/non-concurrent interop */
template <typename TypePolicy,typename Hash,typename Pred,typename Allocator>
using table_core_impl=
table_core<TypePolicy,group15<plain_integral>,table_arrays,
plain_size_control,Hash,Pred,Allocator>;
#include <boost/unordered/detail/foa/ignore_wshadow.hpp>
#if defined(BOOST_MSVC)
#pragma warning(push)
#pragma warning(disable:4714) /* marked as __forceinline not inlined */
#endif
template<typename TypePolicy,typename Hash,typename Pred,typename Allocator>
class table:table_core_impl<TypePolicy,Hash,Pred,Allocator>
{
using super=table_core_impl<TypePolicy,Hash,Pred,Allocator>;
using type_policy=typename super::type_policy;
using group_type=typename super::group_type;
using super::N;
using prober=typename super::prober;
using arrays_type=typename super::arrays_type;
using size_ctrl_type=typename super::size_ctrl_type;
using locator=typename super::locator;
using compatible_concurrent_table=
concurrent_table<TypePolicy,Hash,Pred,Allocator>;
using group_type_pointer=typename boost::pointer_traits<
typename boost::allocator_pointer<Allocator>::type
>::template rebind<group_type>;
friend compatible_concurrent_table;
public:
using key_type=typename super::key_type;
using init_type=typename super::init_type;
using value_type=typename super::value_type;
using element_type=typename super::element_type;
private:
static constexpr bool has_mutable_iterator=
!std::is_same<key_type,value_type>::value;
public:
using hasher=typename super::hasher;
using key_equal=typename super::key_equal;
using allocator_type=typename super::allocator_type;
using pointer=typename super::pointer;
using const_pointer=typename super::const_pointer;
using reference=typename super::reference;
using const_reference=typename super::const_reference;
using size_type=typename super::size_type;
using difference_type=typename super::difference_type;
using const_iterator=table_iterator<type_policy,group_type_pointer,true>;
using iterator=typename std::conditional<
has_mutable_iterator,
table_iterator<type_policy,group_type_pointer,false>,
const_iterator>::type;
using erase_return_type=table_erase_return_type<iterator>;
#if defined(BOOST_UNORDERED_ENABLE_STATS)
using stats=typename super::stats;
#endif
table(
std::size_t n=default_bucket_count,const Hash& h_=Hash(),
const Pred& pred_=Pred(),const Allocator& al_=Allocator()):
super{n,h_,pred_,al_}
{}
table(const table& x)=default;
table(table&& x)=default;
table(const table& x,const Allocator& al_):super{x,al_}{}
table(table&& x,const Allocator& al_):super{std::move(x),al_}{}
table(compatible_concurrent_table&& x):
table(std::move(x),x.exclusive_access()){}
~table()=default;
table& operator=(const table& x)=default;
table& operator=(table&& x)=default;
using super::get_allocator;
iterator begin()noexcept
{
iterator it{this->arrays.groups(),0,this->arrays.elements()};
if(this->arrays.elements()&&
!(this->arrays.groups()[0].match_occupied()&0x1))++it;
return it;
}
const_iterator begin()const noexcept
{return const_cast<table*>(this)->begin();}
iterator end()noexcept{return {};}
const_iterator end()const noexcept{return const_cast<table*>(this)->end();}
const_iterator cbegin()const noexcept{return begin();}
const_iterator cend()const noexcept{return end();}
using super::empty;
using super::size;
using super::max_size;
template<typename... Args>
BOOST_FORCEINLINE std::pair<iterator,bool> emplace(Args&&... args)
{
alloc_cted_insert_type<type_policy,Allocator,Args...> x(
this->al(),std::forward<Args>(args)...);
return emplace_impl(type_policy::move(x.value()));
}
/* Optimization for value_type and init_type, to avoid constructing twice */
template <typename T>
BOOST_FORCEINLINE typename std::enable_if<
detail::is_similar_to_any<T, value_type, init_type>::value,
std::pair<iterator, bool> >::type
emplace(T&& x)
{
return emplace_impl(std::forward<T>(x));
}
/* Optimizations for maps for (k,v) to avoid eagerly constructing value */
template <typename K, typename V>
BOOST_FORCEINLINE
typename std::enable_if<is_emplace_kv_able<table, K>::value,
std::pair<iterator, bool> >::type
emplace(K&& k, V&& v)
{
alloc_cted_or_fwded_key_type<type_policy, Allocator, K&&> x(
this->al(), std::forward<K>(k));
return emplace_impl(
try_emplace_args_t{}, x.move_or_fwd(), std::forward<V>(v));
}
template<typename Key,typename... Args>
BOOST_FORCEINLINE std::pair<iterator,bool> try_emplace(
Key&& x,Args&&... args)
{
return emplace_impl(
try_emplace_args_t{},std::forward<Key>(x),std::forward<Args>(args)...);
}
BOOST_FORCEINLINE std::pair<iterator,bool>
insert(const init_type& x){return emplace_impl(x);}
BOOST_FORCEINLINE std::pair<iterator,bool>
insert(init_type&& x){return emplace_impl(std::move(x));}
/* template<typename=void> tilts call ambiguities in favor of init_type */
template<typename=void>
BOOST_FORCEINLINE std::pair<iterator,bool>
insert(const value_type& x){return emplace_impl(x);}
template<typename=void>
BOOST_FORCEINLINE std::pair<iterator,bool>
insert(value_type&& x){return emplace_impl(std::move(x));}
template<typename T=element_type>
BOOST_FORCEINLINE
typename std::enable_if<
!std::is_same<T,value_type>::value,
std::pair<iterator,bool>
>::type
insert(element_type&& x){return emplace_impl(std::move(x));}
template<
bool dependent_value=false,
typename std::enable_if<
has_mutable_iterator||dependent_value>::type* =nullptr
>
erase_return_type erase(iterator pos)noexcept
{return erase(const_iterator(pos));}
BOOST_FORCEINLINE
erase_return_type erase(const_iterator pos)noexcept
{
super::erase(pos.pc(),pos.p());
return {pos};
}
template<typename Key>
BOOST_FORCEINLINE
auto erase(Key&& x) -> typename std::enable_if<
!std::is_convertible<Key,iterator>::value&&
!std::is_convertible<Key,const_iterator>::value, std::size_t>::type
{
auto it=find(x);
if(it!=end()){
erase(it);
return 1;
}
else return 0;
}
void swap(table& x)
noexcept(noexcept(std::declval<super&>().swap(std::declval<super&>())))
{
super::swap(x);
}
using super::clear;
element_type extract(const_iterator pos)
{
BOOST_ASSERT(pos!=end());
erase_on_exit e{*this,pos};
(void)e;
return std::move(*pos.p());
}
// TODO: should we accept different allocator too?
template<typename Hash2,typename Pred2>
void merge(table<TypePolicy,Hash2,Pred2,Allocator>& x)
{
x.for_all_elements([&,this](group_type* pg,unsigned int n,element_type* p){
erase_on_exit e{x,{pg,n,p}};
if(!emplace_impl(type_policy::move(*p)).second)e.rollback();
});
}
template<typename Hash2,typename Pred2>
void merge(table<TypePolicy,Hash2,Pred2,Allocator>&& x){merge(x);}
using super::hash_function;
using super::key_eq;
template<typename Key>
BOOST_FORCEINLINE iterator find(const Key& x)
{
return make_iterator(super::find(x));
}
template<typename Key>
BOOST_FORCEINLINE const_iterator find(const Key& x)const
{
return const_cast<table*>(this)->find(x);
}
using super::capacity;
using super::load_factor;
using super::max_load_factor;
using super::max_load;
using super::rehash;
using super::reserve;
#if defined(BOOST_UNORDERED_ENABLE_STATS)
using super::get_stats;
using super::reset_stats;
#endif
template<typename Predicate>
friend std::size_t erase_if(table& x,Predicate& pr)
{
using value_reference=typename std::conditional<
std::is_same<key_type,value_type>::value,
const_reference,
reference
>::type;
std::size_t s=x.size();
x.for_all_elements(
[&](group_type* pg,unsigned int n,element_type* p){
if(pr(const_cast<value_reference>(type_policy::value_from(*p)))){
x.super::erase(pg,n,p);
}
});
return std::size_t(s-x.size());
}
friend bool operator==(const table& x,const table& y)
{
return static_cast<const super&>(x)==static_cast<const super&>(y);
}
friend bool operator!=(const table& x,const table& y){return !(x==y);}
private:
template<typename ArraysType>
table(compatible_concurrent_table&& x,arrays_holder<ArraysType,Allocator>&& ah):
super{
std::move(x.h()),std::move(x.pred()),std::move(x.al()),
[&x]{return arrays_type{
x.arrays.groups_size_index,x.arrays.groups_size_mask,
to_pointer<group_type_pointer>(
reinterpret_cast<group_type*>(x.arrays.groups())),
x.arrays.elements_};},
size_ctrl_type{x.size_ctrl.ml,x.size_ctrl.size}}
{
compatible_concurrent_table::arrays_type::delete_group_access(x.al(),x.arrays);
x.arrays=ah.release();
x.size_ctrl.ml=x.initial_max_load();
x.size_ctrl.size=0;
BOOST_UNORDERED_SWAP_STATS(this->cstats,x.cstats);
}
template<typename ExclusiveLockGuard>
table(compatible_concurrent_table&& x,ExclusiveLockGuard):
table(std::move(x),x.make_empty_arrays())
{}
struct erase_on_exit
{
erase_on_exit(table& x_,const_iterator it_):x(x_),it(it_){}
~erase_on_exit(){if(!rollback_)x.erase(it);}
void rollback(){rollback_=true;}
table& x;
const_iterator it;
bool rollback_=false;
};
static inline iterator make_iterator(const locator& l)noexcept
{
return {l.pg,l.n,l.p};
}
template<typename... Args>
BOOST_FORCEINLINE std::pair<iterator,bool> emplace_impl(Args&&... args)
{
const auto &k=this->key_from(std::forward<Args>(args)...);
auto hash=this->hash_for(k);
auto pos0=this->position_for(hash);
auto loc=super::find(k,pos0,hash);
if(loc){
return {make_iterator(loc),false};
}
if(BOOST_LIKELY(this->size_ctrl.size<this->size_ctrl.ml)){
return {
make_iterator(
this->unchecked_emplace_at(pos0,hash,std::forward<Args>(args)...)),
true
};
}
else{
return {
make_iterator(
this->unchecked_emplace_with_rehash(
hash,std::forward<Args>(args)...)),
true
};
}
}
};
#if defined(BOOST_MSVC)
#pragma warning(pop) /* C4714 */
#endif
#include <boost/unordered/detail/foa/restore_wshadow.hpp>
} /* namespace foa */
} /* namespace detail */
} /* namespace unordered */
} /* namespace boost */
#endif
Reference in New Issue View Git Blame Copy Permalink