Fix LWG issue 2469 - Use piecewise construction in map::operator[].
map's allocator may only be used to construct objects of 'value_type',
or in this case 'pair<const Key, Value>'. In order to respect this requirement
in operator[], which requires default constructing the 'mapped_type', we have
to use pair's piecewise constructor with '(tuple<Kep>, tuple<>)'.
Unfortunately we still need to provide a fallback implementation for C++03
since we don't have <tuple>. Even worse this fallback is the last remaining
user of '__hash_map_node_destructor' and '__construct_node_with_key'.
This patch also switches try_emplace over to __tree.__emplace_unique_key_args.
llvm-svn: 264989
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 54f0cda625d0fee9b357fc98d4036cbf7b98a424
diff --git a/include/map b/include/map
index a459146..29d068a 100644
--- a/include/map
+++ b/include/map
@@ -1026,7 +1026,7 @@
size_type max_size() const _NOEXCEPT {return __tree_.max_size();}
mapped_type& operator[](const key_type& __k);
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#ifndef _LIBCPP_CXX03_LANG
mapped_type& operator[](key_type&& __k);
#endif
@@ -1105,62 +1105,45 @@
#endif // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
#if _LIBCPP_STD_VER > 14
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
-#ifndef _LIBCPP_HAS_NO_VARIADICS
+
template <class... _Args>
_LIBCPP_INLINE_VISIBILITY
pair<iterator, bool> try_emplace(const key_type& __k, _Args&&... __args)
{
- iterator __p = lower_bound(__k);
- if ( __p != end() && !key_comp()(__k, __p->first))
- return _VSTD::make_pair(__p, false);
- else
- return _VSTD::make_pair(
- emplace_hint(__p,
- _VSTD::piecewise_construct, _VSTD::forward_as_tuple(__k),
- _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)),
- true);
+ return __tree_.__emplace_unique_key_args(__k,
+ _VSTD::piecewise_construct,
+ _VSTD::forward_as_tuple(__k),
+ _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
}
template <class... _Args>
_LIBCPP_INLINE_VISIBILITY
pair<iterator, bool> try_emplace(key_type&& __k, _Args&&... __args)
{
- iterator __p = lower_bound(__k);
- if ( __p != end() && !key_comp()(__k, __p->first))
- return _VSTD::make_pair(__p, false);
- else
- return _VSTD::make_pair(
- emplace_hint(__p,
- _VSTD::piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__k)),
- _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)),
- true);
+ return __tree_.__emplace_unique_key_args(__k,
+ _VSTD::piecewise_construct,
+ _VSTD::forward_as_tuple(_VSTD::move(__k)),
+ _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
}
template <class... _Args>
_LIBCPP_INLINE_VISIBILITY
iterator try_emplace(const_iterator __h, const key_type& __k, _Args&&... __args)
{
- iterator __p = lower_bound(__k);
- if ( __p != end() && !key_comp()(__k, __p->first))
- return __p;
- else
- return emplace_hint(__p,
- _VSTD::piecewise_construct, _VSTD::forward_as_tuple(__k),
- _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
+ return __tree_.__emplace_hint_unique_key_args(__h.__i_, __k,
+ _VSTD::piecewise_construct,
+ _VSTD::forward_as_tuple(__k),
+ _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
}
template <class... _Args>
_LIBCPP_INLINE_VISIBILITY
iterator try_emplace(const_iterator __h, key_type&& __k, _Args&&... __args)
{
- iterator __p = lower_bound(__k);
- if ( __p != end() && !key_comp()(__k, __p->first))
- return __p;
- else
- return emplace_hint(__p,
- _VSTD::piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__k)),
- _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
+ return __tree_.__emplace_hint_unique_key_args(__h.__i_, __k,
+ _VSTD::piecewise_construct,
+ _VSTD::forward_as_tuple(_VSTD::move(__k)),
+ _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
}
template <class _Vp>
@@ -1175,7 +1158,7 @@
}
return _VSTD::make_pair(emplace_hint(__p, __k, _VSTD::forward<_Vp>(__v)), true);
}
-
+
template <class _Vp>
_LIBCPP_INLINE_VISIBILITY
pair<iterator, bool> insert_or_assign(key_type&& __k, _Vp&& __v)
@@ -1214,8 +1197,7 @@
}
return emplace_hint(__h, _VSTD::move(__k), _VSTD::forward<_Vp>(__v));
}
-#endif
-#endif
+
#endif
_LIBCPP_INLINE_VISIBILITY
@@ -1321,11 +1303,9 @@
typedef __map_node_destructor<__node_allocator> _Dp;
typedef unique_ptr<__node, _Dp> __node_holder;
-#ifndef _LIBCPP_CXX03_LANG
- __node_holder __construct_node_with_key(key_type&& __k);
-#endif
-
+#ifdef _LIBCPP_CXX03_LANG
__node_holder __construct_node_with_key(const key_type& __k);
+#endif
__node_base_pointer const&
__find_equal_key(__node_base_pointer& __parent, const key_type& __k) const;
@@ -1400,22 +1380,11 @@
}
}
-
-template <class _Key, class _Tp, class _Compare, class _Allocator>
-typename map<_Key, _Tp, _Compare, _Allocator>::__node_holder
-map<_Key, _Tp, _Compare, _Allocator>::__construct_node_with_key(key_type&& __k)
-{
- __node_allocator& __na = __tree_.__node_alloc();
- __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
- __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.first), _VSTD::move(__k));
- __h.get_deleter().__first_constructed = true;
- __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__cc.second));
- __h.get_deleter().__second_constructed = true;
- return __h;
-}
-
#endif // !_LIBCPP_CXX03_LANG
+
+#ifdef _LIBCPP_CXX03_LANG
+
template <class _Key, class _Tp, class _Compare, class _Allocator>
typename map<_Key, _Tp, _Compare, _Allocator>::__node_holder
map<_Key, _Tp, _Compare, _Allocator>::__construct_node_with_key(const key_type& __k)
@@ -1445,25 +1414,29 @@
return __r->__value_.__cc.second;
}
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#else
+
+template <class _Key, class _Tp, class _Compare, class _Allocator>
+_Tp&
+map<_Key, _Tp, _Compare, _Allocator>::operator[](const key_type& __k)
+{
+ return __tree_.__emplace_unique_key_args(__k,
+ _VSTD::piecewise_construct,
+ _VSTD::forward_as_tuple(__k),
+ _VSTD::forward_as_tuple()).first->__cc.second;
+}
template <class _Key, class _Tp, class _Compare, class _Allocator>
_Tp&
map<_Key, _Tp, _Compare, _Allocator>::operator[](key_type&& __k)
{
- __node_base_pointer __parent;
- __node_base_pointer& __child = __find_equal_key(__parent, __k);
- __node_pointer __r = static_cast<__node_pointer>(__child);
- if (__child == nullptr)
- {
- __node_holder __h = __construct_node_with_key(_VSTD::move(__k));
- __tree_.__insert_node_at(__parent, __child, static_cast<__node_base_pointer>(__h.get()));
- __r = __h.release();
- }
- return __r->__value_.__cc.second;
+ return __tree_.__emplace_unique_key_args(__k,
+ _VSTD::piecewise_construct,
+ _VSTD::forward_as_tuple(_VSTD::move(__k)),
+ _VSTD::forward_as_tuple()).first->__cc.second;
}
-#endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#endif // !_LIBCPP_CXX03_LANG
template <class _Key, class _Tp, class _Compare, class _Allocator>
_Tp&