[libcxx] r264989 - Fix LWG issue 2469 - Use piecewise construction in map::operator[].
Eric Fiselier via cfe-commits
cfe-commits at lists.llvm.org
Wed Mar 30 20:13:37 PDT 2016
Author: ericwf
Date: Wed Mar 30 22:13:37 2016
New Revision: 264989
URL: http://llvm.org/viewvc/llvm-project?rev=264989&view=rev
Log:
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.
Modified:
libcxx/trunk/include/map
libcxx/trunk/test/std/containers/associative/map/map.access/index_key.pass.cpp
libcxx/trunk/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp
Modified: libcxx/trunk/include/map
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/map?rev=264989&r1=264988&r2=264989&view=diff
==============================================================================
--- libcxx/trunk/include/map (original)
+++ libcxx/trunk/include/map Wed Mar 30 22:13:37 2016
@@ -1026,7 +1026,7 @@ public:
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 @@ public:
#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 @@ public:
}
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 @@ public:
}
return emplace_hint(__h, _VSTD::move(__k), _VSTD::forward<_Vp>(__v));
}
-#endif
-#endif
+
#endif
_LIBCPP_INLINE_VISIBILITY
@@ -1321,11 +1303,9 @@ private:
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;
@@ -1400,21 +1380,10 @@ map<_Key, _Tp, _Compare, _Allocator>::ma
}
}
+#endif // !_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(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
@@ -1445,25 +1414,29 @@ map<_Key, _Tp, _Compare, _Allocator>::op
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&
Modified: libcxx/trunk/test/std/containers/associative/map/map.access/index_key.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/containers/associative/map/map.access/index_key.pass.cpp?rev=264989&r1=264988&r2=264989&view=diff
==============================================================================
--- libcxx/trunk/test/std/containers/associative/map/map.access/index_key.pass.cpp (original)
+++ libcxx/trunk/test/std/containers/associative/map/map.access/index_key.pass.cpp Wed Mar 30 22:13:37 2016
@@ -16,8 +16,13 @@
#include <map>
#include <cassert>
+#include "test_macros.h"
+#include "count_new.hpp"
#include "min_allocator.h"
#include "private_constructor.hpp"
+#if TEST_STD_VER >= 11
+#include "container_test_types.h"
+#endif
int main()
{
@@ -46,7 +51,7 @@ int main()
assert(m[6] == 6.5);
assert(m.size() == 8);
}
-#if __cplusplus >= 201103L
+#if TEST_STD_VER >= 11
{
typedef std::pair<const int, double> V;
V ar[] =
@@ -73,8 +78,42 @@ int main()
assert(m[6] == 6.5);
assert(m.size() == 8);
}
+ {
+ // Use "container_test_types.h" to check what arguments get passed
+ // to the allocator for operator[]
+ using Container = TCT::map<>;
+ using Key = Container::key_type;
+ using MappedType = Container::mapped_type;
+ using ValueTp = Container::value_type;
+ ConstructController* cc = getConstructController();
+ cc->reset();
+ {
+ Container c;
+ const Key k(1);
+ cc->expect<std::piecewise_construct_t const&, std::tuple<Key const&>&&, std::tuple<>&&>();
+ MappedType& mref = c[k];
+ assert(!cc->unchecked());
+ {
+ DisableAllocationGuard g;
+ MappedType& mref2 = c[k];
+ assert(&mref == &mref2);
+ }
+ }
+ {
+ Container c;
+ Key k(1);
+ cc->expect<std::piecewise_construct_t const&, std::tuple<Key const&>&&, std::tuple<>&&>();
+ MappedType& mref = c[k];
+ assert(!cc->unchecked());
+ {
+ DisableAllocationGuard g;
+ MappedType& mref2 = c[k];
+ assert(&mref == &mref2);
+ }
+ }
+ }
#endif
-#if _LIBCPP_STD_VER > 11
+#if TEST_STD_VER > 11
{
typedef std::pair<const int, double> V;
V ar[] =
Modified: libcxx/trunk/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp?rev=264989&r1=264988&r2=264989&view=diff
==============================================================================
--- libcxx/trunk/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp (original)
+++ libcxx/trunk/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp Wed Mar 30 22:13:37 2016
@@ -7,6 +7,8 @@
//
//===----------------------------------------------------------------------===//
+// UNSUPPORTED: c++98, c++03
+
// <map>
// class map
@@ -17,12 +19,13 @@
#include <cassert>
#include "test_macros.h"
+#include "count_new.hpp"
#include "MoveOnly.h"
#include "min_allocator.h"
+#include "container_test_types.h"
int main()
{
-#if TEST_STD_VER >= 11
{
std::map<MoveOnly, double> m;
assert(m.size() == 0);
@@ -52,5 +55,27 @@ int main()
assert(m[6] == 6.5);
assert(m.size() == 2);
}
-#endif
+ {
+ // Use "container_test_types.h" to check what arguments get passed
+ // to the allocator for operator[]
+ using Container = TCT::map<>;
+ using Key = Container::key_type;
+ using MappedType = Container::mapped_type;
+ using ValueTp = Container::value_type;
+ ConstructController* cc = getConstructController();
+ cc->reset();
+ {
+ Container c;
+ Key k(1);
+ cc->expect<std::piecewise_construct_t const&, std::tuple<Key &&>&&, std::tuple<>&&>();
+ MappedType& mref = c[std::move(k)];
+ assert(!cc->unchecked());
+ {
+ Key k2(1);
+ DisableAllocationGuard g;
+ MappedType& mref2 = c[std::move(k2)];
+ assert(&mref == &mref2);
+ }
+ }
+ }
}
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