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[libc++] Simplify a bunch of noexcept specifications #166397

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[libc++] Simplify a bunch of noexcept specifications #166397

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60 changes: 17 additions & 43 deletions libcxx/include/__hash_table
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Original file line number Diff line number Diff line change
Expand Up @@ -518,13 +518,13 @@ public:
_LIBCPP_HIDE_FROM_ABI __bucket_list_deallocator() _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
: __size_(0) {}

_LIBCPP_HIDE_FROM_ABI __bucket_list_deallocator(const allocator_type& __a, size_type __size)
_NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
: __size_(__size), __alloc_(__a) {}
_LIBCPP_HIDE_FROM_ABI __bucket_list_deallocator(const allocator_type& __a, size_type __size) _NOEXCEPT
: __size_(__size),
__alloc_(__a) {}

_LIBCPP_HIDE_FROM_ABI __bucket_list_deallocator(__bucket_list_deallocator&& __x)
_NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
: __size_(std::move(__x.__size_)), __alloc_(std::move(__x.__alloc_)) {
_LIBCPP_HIDE_FROM_ABI __bucket_list_deallocator(__bucket_list_deallocator&& __x) _NOEXCEPT
: __size_(std::move(__x.__size_)),
__alloc_(std::move(__x.__alloc_)) {
__x.size() = 0;
}

Expand Down Expand Up @@ -740,17 +740,14 @@ public:
_LIBCPP_HIDE_FROM_ABI __hash_table(const __hash_table& __u, const allocator_type& __a);
_LIBCPP_HIDE_FROM_ABI __hash_table(__hash_table&& __u) _NOEXCEPT_(
is_nothrow_move_constructible<__bucket_list>::value&& is_nothrow_move_constructible<__first_node>::value&&
is_nothrow_move_constructible<__node_allocator>::value&& is_nothrow_move_constructible<hasher>::value&&
is_nothrow_move_constructible<key_equal>::value);
is_nothrow_move_constructible<hasher>::value&& is_nothrow_move_constructible<key_equal>::value);
_LIBCPP_HIDE_FROM_ABI __hash_table(__hash_table&& __u, const allocator_type& __a);
_LIBCPP_HIDE_FROM_ABI ~__hash_table();

_LIBCPP_HIDE_FROM_ABI __hash_table& operator=(const __hash_table& __u);
_LIBCPP_HIDE_FROM_ABI __hash_table& operator=(__hash_table&& __u)
_NOEXCEPT_(is_nothrow_move_assignable<hasher>::value&& is_nothrow_move_assignable<key_equal>::value &&
((__node_traits::propagate_on_container_move_assignment::value &&
is_nothrow_move_assignable<__node_allocator>::value) ||
allocator_traits<__node_allocator>::is_always_equal::value));
_NOEXCEPT_(is_nothrow_move_assignable<hasher>::value&& is_nothrow_move_assignable<key_equal>::value&&
__is_allocator_aware_container_move_nothrow_v<allocator_type>);
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@ldionne ldionne Nov 19, 2025

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Let's add a libc++ specific test for these properties that we were apparently not testing previously.

Or if we're already testing this somehow, there should be a test changing in std::unordered_map and friends.

template <class _InputIterator>
_LIBCPP_HIDE_FROM_ABI void __assign_unique(_InputIterator __first, _InputIterator __last);
template <class _InputIterator>
Expand Down Expand Up @@ -944,14 +941,7 @@ public:
_LIBCPP_HIDE_FROM_ABI pair<const_iterator, const_iterator> __equal_range_multi(const _Key& __k) const;

_LIBCPP_HIDE_FROM_ABI void swap(__hash_table& __u)
#if _LIBCPP_STD_VER <= 11
_NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal> &&
(!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value ||
__is_nothrow_swappable_v<__pointer_allocator>) &&
(!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>));
#else
_NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal>);
#endif

_LIBCPP_HIDE_FROM_ABI size_type max_bucket_count() const _NOEXCEPT { return max_size(); }
_LIBCPP_HIDE_FROM_ABI size_type bucket_size(size_type __n) const;
Expand Down Expand Up @@ -1011,15 +1001,11 @@ private:

_LIBCPP_HIDE_FROM_ABI void __move_assign(__hash_table& __u, false_type);
_LIBCPP_HIDE_FROM_ABI void __move_assign(__hash_table& __u, true_type)
_NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value&& is_nothrow_move_assignable<hasher>::value&&
is_nothrow_move_assignable<key_equal>::value);
_LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__hash_table& __u) _NOEXCEPT_(
!__node_traits::propagate_on_container_move_assignment::value ||
(is_nothrow_move_assignable<__pointer_allocator>::value && is_nothrow_move_assignable<__node_allocator>::value)) {
_NOEXCEPT_(is_nothrow_move_assignable<hasher>::value&& is_nothrow_move_assignable<key_equal>::value);
_LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__hash_table& __u) _NOEXCEPT {
__move_assign_alloc(__u, integral_constant<bool, __node_traits::propagate_on_container_move_assignment::value>());
}
_LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__hash_table& __u, true_type) _NOEXCEPT_(
is_nothrow_move_assignable<__pointer_allocator>::value&& is_nothrow_move_assignable<__node_allocator>::value) {
_LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__hash_table& __u, true_type) _NOEXCEPT {
__bucket_list_.get_deleter().__alloc() = std::move(__u.__bucket_list_.get_deleter().__alloc());
__node_alloc() = std::move(__u.__node_alloc());
}
Expand Down Expand Up @@ -1132,8 +1118,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(const __hash_table& __u,
template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u) _NOEXCEPT_(
is_nothrow_move_constructible<__bucket_list>::value&& is_nothrow_move_constructible<__first_node>::value&&
is_nothrow_move_constructible<__node_allocator>::value&& is_nothrow_move_constructible<hasher>::value&&
is_nothrow_move_constructible<key_equal>::value)
is_nothrow_move_constructible<hasher>::value&& is_nothrow_move_constructible<key_equal>::value)
: __bucket_list_(std::move(__u.__bucket_list_)),
__first_node_(std::move(__u.__first_node_)),
__node_alloc_(std::move(__u.__node_alloc_)),
Expand Down Expand Up @@ -1278,8 +1263,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__detach() _NOEXCEPT {

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(__hash_table& __u, true_type)
_NOEXCEPT_(is_nothrow_move_assignable<__node_allocator>::value&& is_nothrow_move_assignable<hasher>::value&&
is_nothrow_move_assignable<key_equal>::value) {
_NOEXCEPT_(is_nothrow_move_assignable<hasher>::value&& is_nothrow_move_assignable<key_equal>::value) {
clear();
__bucket_list_.reset(__u.__bucket_list_.release());
__bucket_list_.get_deleter().size() = __u.__bucket_list_.get_deleter().size();
Expand Down Expand Up @@ -1324,10 +1308,8 @@ void __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(__hash_table& __u,

template <class _Tp, class _Hash, class _Equal, class _Alloc>
inline __hash_table<_Tp, _Hash, _Equal, _Alloc>& __hash_table<_Tp, _Hash, _Equal, _Alloc>::operator=(__hash_table&& __u)
_NOEXCEPT_(is_nothrow_move_assignable<hasher>::value&& is_nothrow_move_assignable<key_equal>::value &&
((__node_traits::propagate_on_container_move_assignment::value &&
is_nothrow_move_assignable<__node_allocator>::value) ||
allocator_traits<__node_allocator>::is_always_equal::value)) {
_NOEXCEPT_(is_nothrow_move_assignable<hasher>::value&& is_nothrow_move_assignable<key_equal>::value&&
__is_allocator_aware_container_move_nothrow_v<allocator_type>) {
__move_assign(__u, integral_constant<bool, __node_traits::propagate_on_container_move_assignment::value>());
return *this;
}
Expand Down Expand Up @@ -2060,15 +2042,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__equal_range_multi(const _Key& __k) c

template <class _Tp, class _Hash, class _Equal, class _Alloc>
void __hash_table<_Tp, _Hash, _Equal, _Alloc>::swap(__hash_table& __u)
#if _LIBCPP_STD_VER <= 11
_NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal> &&
(!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value ||
__is_nothrow_swappable_v<__pointer_allocator>) &&
(!__node_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__node_allocator>))
#else
_NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal>)
#endif
{
_NOEXCEPT_(__is_nothrow_swappable_v<hasher>&& __is_nothrow_swappable_v<key_equal>) {
_LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(
__node_traits::propagate_on_container_swap::value || this->__node_alloc() == __u.__node_alloc(),
"unordered container::swap: Either propagate_on_container_swap "
Expand Down
4 changes: 4 additions & 0 deletions libcxx/include/__memory/allocator_traits.h
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Original file line number Diff line number Diff line change
Expand Up @@ -374,6 +374,10 @@ inline const bool __is_cpp17_copy_insertable_v =
(!__is_std_allocator_v<_Alloc> &&
__has_construct_v<_Alloc, typename _Alloc::value_type*, const typename _Alloc::value_type&>));

template <typename _Alloc, typename _Traits = allocator_traits<_Alloc> >
inline const bool __is_allocator_aware_container_move_nothrow_v =
_Traits::propagate_on_container_move_assignment::value || _Traits::is_always_equal::value;

_LIBCPP_END_NAMESPACE_STD

_LIBCPP_POP_MACROS
Expand Down
37 changes: 0 additions & 37 deletions libcxx/include/__memory/noexcept_move_assign_container.h
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This file was deleted.

37 changes: 11 additions & 26 deletions libcxx/include/__split_buffer
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -28,8 +28,6 @@
#include <__type_traits/conditional.h>
#include <__type_traits/enable_if.h>
#include <__type_traits/integral_constant.h>
#include <__type_traits/is_nothrow_assignable.h>
#include <__type_traits/is_nothrow_constructible.h>
#include <__type_traits/is_swappable.h>
#include <__type_traits/is_trivially_destructible.h>
#include <__type_traits/is_trivially_relocatable.h>
Expand Down Expand Up @@ -184,8 +182,7 @@ public:
}

_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
__copy_without_alloc(__split_buffer_pointer_layout const& __other)
_NOEXCEPT_(is_nothrow_copy_assignable<pointer>::value) {
__copy_without_alloc(__split_buffer_pointer_layout const& __other) _NOEXCEPT {
__front_cap_ = __other.__front_cap_;
__begin_ = __other.__begin_;
__end_ = __other.__end_;
Expand Down Expand Up @@ -341,8 +338,7 @@ public:
}

_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
__copy_without_alloc(__split_buffer_size_layout const& __other)
_NOEXCEPT_(is_nothrow_copy_assignable<pointer>::value) {
__copy_without_alloc(__split_buffer_size_layout const& __other) _NOEXCEPT {
__front_cap_ = __other.__front_cap_;
__begin_ = __other.__begin_;
__cap_ = __other.__cap_;
Expand Down Expand Up @@ -497,15 +493,11 @@ public:
_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
__split_buffer(size_type __cap, size_type __start, __alloc_rr& __a);

_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c)
_NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c) _NOEXCEPT;

_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer(__split_buffer&& __c, const __alloc_rr& __a);

_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer& operator=(__split_buffer&& __c)
_NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value &&
is_nothrow_move_assignable<allocator_type>::value) ||
!__alloc_traits::propagate_on_container_move_assignment::value);
_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI __split_buffer& operator=(__split_buffer&& __c) _NOEXCEPT;

_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~__split_buffer();

Expand Down Expand Up @@ -559,8 +551,7 @@ public:
_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last, false_type) _NOEXCEPT;
_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __destruct_at_end(pointer __new_last, true_type) _NOEXCEPT;

_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void swap(__split_buffer& __x)
_NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__alloc_rr>);
_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void swap(__split_buffer& __x) _NOEXCEPT;

_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __invariants() const {
if (__front_cap() == nullptr) {
Expand Down Expand Up @@ -594,8 +585,8 @@ public:
}

private:
_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign_alloc(__split_buffer& __c, true_type)
_NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value) {
_LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
__move_assign_alloc(__split_buffer& __c, true_type) _NOEXCEPT {
__get_allocator() = std::move(__c.__get_allocator());
}

Expand Down Expand Up @@ -740,8 +731,7 @@ _LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator, _Layout>::~__split
}

template <class _Tp, class _Allocator, template <class, class, class> class _Layout>
_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator, _Layout>::__split_buffer(__split_buffer&& __c)
_NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator, _Layout>::__split_buffer(__split_buffer&& __c) _NOEXCEPT
: __base_type(std::move(__c)) {
__c.__reset();
}
Expand All @@ -767,10 +757,7 @@ __split_buffer<_Tp, _Allocator, _Layout>::__split_buffer(__split_buffer&& __c, c

template <class _Tp, class _Allocator, template <class, class, class> class _Layout>
_LIBCPP_CONSTEXPR_SINCE_CXX20 __split_buffer<_Tp, _Allocator, _Layout>&
__split_buffer<_Tp, _Allocator, _Layout>::operator=(__split_buffer&& __c)
_NOEXCEPT_((__alloc_traits::propagate_on_container_move_assignment::value &&
is_nothrow_move_assignable<allocator_type>::value) ||
!__alloc_traits::propagate_on_container_move_assignment::value) {
__split_buffer<_Tp, _Allocator, _Layout>::operator=(__split_buffer&& __c) _NOEXCEPT {
clear();
shrink_to_fit();
__copy_without_alloc(__c);
Expand All @@ -780,8 +767,7 @@ __split_buffer<_Tp, _Allocator, _Layout>::operator=(__split_buffer&& __c)
}

template <class _Tp, class _Allocator, template <class, class, class> class _Layout>
_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator, _Layout>::swap(__split_buffer& __x)
_NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value || __is_nothrow_swappable_v<__alloc_rr>) {
_LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator, _Layout>::swap(__split_buffer& __x) _NOEXCEPT {
__base_type::swap(__x);
}

Expand Down Expand Up @@ -852,8 +838,7 @@ _LIBCPP_CONSTEXPR_SINCE_CXX20 void __split_buffer<_Tp, _Allocator, _Layout>::emp

template <class _Tp, class _Allocator, template <class, class, class> class _Layout>
_LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI void
swap(__split_buffer<_Tp, _Allocator, _Layout>& __x, __split_buffer<_Tp, _Allocator, _Layout>& __y)
_NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) {
swap(__split_buffer<_Tp, _Allocator, _Layout>& __x, __split_buffer<_Tp, _Allocator, _Layout>& __y) _NOEXCEPT {
__x.swap(__y);
}

Expand Down
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