These containers type-punned between pair<K, V> and pair<const K, V> as an
optimization. This commit instead provides access to the pair via a pair of
references that assign through to the underlying object. It's still undefined to
mutate a const object, but clang doesn't optimize on this for data members, so
this should be safe.
Differential revision: https://reviews.llvm.org/D47607
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@333948 91177308-0d34-0410-b5e6-96231b3b80d8
The __unordered_map_equal and __unordered_map_hash wrappers
attempt to swap const qualified predicates whenever the predicate
is empty, and is subject to the EBO.
Swapping const values seems blatently incorrect. This patch removes
the const qualifier so the values are swapped as non-const.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@300154 91177308-0d34-0410-b5e6-96231b3b80d8
The name _LIBCPP_TYPE_VIS_ONLY is no longer accurate because both
_LIBCPP_TYPE_VIS and _LIBCPP_TYPE_VIS_ONLY expand to
__attribute__((__type_visibility__)) with Clang. The only remaining difference
is that _LIBCPP_TYPE_VIS_ONLY can be applied to templates whereas
_LIBCPP_TYPE_VIS cannot (due to dllimport/dllexport not being allowed on
templates).
This patch renames _LIBCPP_TYPE_VIS_ONLY to _LIBCPP_TEMPLATE_VIS.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@291035 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This patch fixes a couple of typos that cause compilation errors when application includes <unordered_map> and enables the libc++'s debugging capabilities.
Reviewers: EricWF
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24883
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@282446 91177308-0d34-0410-b5e6-96231b3b80d8
unordered_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'.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@260601 91177308-0d34-0410-b5e6-96231b3b80d8
This patch is fairly large and contains a number of changes. The main change
is teaching '__hash_table' how to handle '__hash_value_type'. Unfortunately
this change is a rampant layering violation, but it's required to make
unordered_map conforming without re-writing all of __hash_table.
After this change 'unordered_map' can delegate to '__hash_table' in almost all cases.
The major changes found in this patch are:
* Teach __hash_table to differentiate between the true container value type
and the node value type by introducing the "__container_value_type" and
"__node_value_type" typedefs. In the case of unordered_map '__container_value_type'
is 'pair<const Key, Value>' and '__node_value_type' is '__hash_value_type'.
* Switch almost all overloads in '__hash_table' previously taking 'value_type'
(AKA '__node_value_type) to take '__container_value_type' instead. Previously
'pair<K, V>' would be implicitly converted to '__hash_value_type<K, V>' because
of the function signature.
* Add '__get_key', '__get_value', '__get_ptr', and '__move' static functions to
'__key_value_types'. These functions allow '__hash_table' to unwrap
'__node_value_type' objects into '__container_value_type' and its sub-parts.
* Pass '__hash_value_type::__value_' to 'a.construct(p, ...)' instead of
'__hash_value_type' itself. The C++14 standard requires that 'a.construct()'
and 'a.destroy()' are only ever instantiated for the containers value type.
* Remove '__hash_value_type's constructors and destructors. We should never
construct an instance of this type.
(TODO this is UB but we already do it in plenty of places).
* Add a generic "try-emplace" function to '__hash_table' called
'__emplace_unique_key_args(Key const&, Args...)'.
The following changes were done as cleanup:
* Introduce the '_LIBCPP_CXX03_LANG' macro to be used in place of
'_LIBCPP_HAS_NO_VARIADICS' or '_LIBCPP_HAS_NO_RVALUE_REFERENCE'.
* Cleanup C++11 only overloads that assume an incomplete C++11 implementation.
For example this patch removes the __construct_node overloads that do
manual pack expansion.
* Forward 'unordered_map::emplace' to '__hash_table' and remove dead code
resulting from the change. This includes almost all
'unordered_map::__construct_node' overloads.
The following changes are planed for future revisions:
* Fix LWG issue #2469 by delegating 'unordered_map::operator[]' to use
'__emplace_unique_key_args'.
* Rewrite 'unordered_map::try_emplace' in terms of '__emplace_unique_key_args'.
* Optimize '__emplace_unique' to call '__emplace_unique_key_args' when possible.
This prevent unneeded allocations when inserting duplicate entries.
The additional follow up work needed after this patch:
* Respect the lifetime rules for '__hash_value_type' by actually constructing it.
* Make '__insert_multi' act similar to '__insert_unique' for objects of type
'T&' and 'T const &&' with 'T = __container_value_type'.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@260514 91177308-0d34-0410-b5e6-96231b3b80d8
This patch is fairly large and contains a number of changes. The main change
is teaching '__hash_table' how to handle '__hash_value_type'. Unfortunately
this change is a rampant layering violation, but it's required to make
unordered_map conforming without re-writing all of __hash_table.
After this change 'unordered_map' can delegate to '__hash_table' in almost all cases.
The major changes found in this patch are:
* Teach __hash_table to differentiate between the true container value type
and the node value type by introducing the "__container_value_type" and
"__node_value_type" typedefs. In the case of unordered_map '__container_value_type'
is 'pair<const Key, Value>' and '__node_value_type' is '__hash_value_type'.
* Switch almost all overloads in '__hash_table' previously taking 'value_type'
(AKA '__node_value_type) to take '__container_value_type' instead. Previously
'pair<K, V>' would be implicitly converted to '__hash_value_type<K, V>' because
of the function signature.
* Add '__get_key', '__get_value', '__get_ptr', and '__move' static functions to
'__key_value_types'. These functions allow '__hash_table' to unwrap
'__node_value_type' objects into '__container_value_type' and its sub-parts.
* Pass '__hash_value_type::__value_' to 'a.construct(p, ...)' instead of
'__hash_value_type' itself. The C++14 standard requires that 'a.construct()'
and 'a.destroy()' are only ever instantiated for the containers value type.
* Remove '__hash_value_type's constructors and destructors. We should never
construct an instance of this type.
(TODO this is UB but we already do it in plenty of places).
* Add a generic "try-emplace" function to '__hash_table' called
'__emplace_unique_key_args(Key const&, Args...)'.
The following changes were done as cleanup:
* Introduce the '_LIBCPP_CXX03_LANG' macro to be used in place of
'_LIBCPP_HAS_NO_VARIADICS' or '_LIBCPP_HAS_NO_RVALUE_REFERENCE'.
* Cleanup C++11 only overloads that assume an incomplete C++11 implementation.
For example this patch removes the __construct_node overloads that do
manual pack expansion.
* Forward 'unordered_map::emplace' to '__hash_table' and remove dead code
resulting from the change. This includes almost all
'unordered_map::__construct_node' overloads.
The following changes are planed for future revisions:
* Fix LWG issue #2469 by delegating 'unordered_map::operator[]' to use
'__emplace_unique_key_args'.
* Rewrite 'unordered_map::try_emplace' in terms of '__emplace_unique_key_args'.
* Optimize '__emplace_unique' to call '__emplace_unique_key_args' when possible.
This prevent unneeded allocations when inserting duplicate entries.
The additional follow up work needed after this patch:
* Respect the lifetime rules for '__hash_value_type' by actually constructing it.
* Make '__insert_multi' act similar to '__insert_unique' for objects of type
'T&' and 'T const &&' with 'T = __container_value_type'.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@260513 91177308-0d34-0410-b5e6-96231b3b80d8
This time I kept <ext/hash_map> working!
This patch is the first in a series of patches that's meant to better
support unordered_map. unordered_map has a special "value_type" that
differs from pair<const Key, Value>. In order to meet the EmplaceConstructible
and CopyInsertable requirements we need to teach __hash_table about this
special value_type.
This patch creates a "__hash_node_types" traits class that contains
all of the typedefs needed by the unordered containers and it's iterators.
These typedefs include ones for each node type and node pointer type,
as well as special typedefs for "unordered_map"'s value type.
As a result of this change all of the unordered containers now all support
incomplete types.
As a drive-by fix I changed the difference_type in __hash_table to always
be ptrdiff_t. There is a corresponding change to size_type but it cannot
take affect until an ABI break.
This patch will be followed up shortly with fixes for various unordered_map
bugs and problems.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@260431 91177308-0d34-0410-b5e6-96231b3b80d8
This patch is the first in a series of patches that's meant to better
support unordered_map. unordered_map has a special "value_type" that
differs from pair<const Key, Value>. In order to meet the EmplaceConstructible
and CopyInsertable requirements we need to teach __hash_table about this
special value_type.
This patch creates a "__hash_node_types" traits class that contains
all of the typedefs needed by the unordered containers and it's iterators.
These typedefs include ones for each node type and node pointer type,
as well as special typedefs for "unordered_map"'s value type.
As a result of this change all of the unordered containers now all support
incomplete types.
As a drive-by fix I changed the difference_type in __hash_table to always
be ptrdiff_t. There is a corresponding change to size_type but it cannot
take affect until an ABI break.
This patch will be followed up shortly with fixes for various unordered_map
fixes.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@260012 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r258575. EricWF sent me an email (no link since it
was off-list) requesting to review this pre-commit instead of
post-commit.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@258625 91177308-0d34-0410-b5e6-96231b3b80d8
An upcoming commit will add an optimization to insert() that avoids
unnecessary mallocs when we can safely extract the key type. This
commit shares code between emplace() and insert():
- if emplace() is given a single argument, and
- value_type is constructible from that argument
so that we have a single code path for the two.
I also updated the debug version of emplace_hint() to defer to
emplace(), like the non-debug version does.
In both cases, there should be NFC here.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@258575 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Throughout the libc++ headers, there are a few instances where
_VSTD::move() is used to return a local variable. Howard commented in
r189039 that these were there "for non-obvious reasons such as to help
things limp along in C++03 language mode".
However, when compiling these headers with warnings on, and in C++11 or
higher mode (like we do in FreeBSD), they cause the following complaints
about pessimizing moves:
In file included from tests.cpp:26:
In file included from tests.hpp:29:
/usr/include/c++/v1/map:1368:12: error: moving a local object in a return statement prevents copy elision [-Werror,-Wpessimizing-move]
return _VSTD::move(__h); // explicitly moved for C++03
^
/usr/include/c++/v1/__config:368:15: note: expanded from macro '_VSTD'
#define _VSTD std::_LIBCPP_NAMESPACE
^
Attempt to fix this by adding a _LIBCPP_EXPLICIT_MOVE() macro to
__config, which gets defined to _VSTD::move for pre-C++11, and to
nothing for C++11 and later.
I am not completely satisfied with the macro name (I also considered
_LIBCPP_COMPAT_MOVE and some other variants), so suggestions are
welcome. :)
Reviewers: mclow.lists, howard.hinnant, EricWF
Subscribers: arthur.j.odwyer, cfe-commits
Differential Revision: http://reviews.llvm.org/D11394
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@245421 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Currently we only enable the use of __is_final(...) with Clang. GCC also provides __is_final(...) since 4.7 in all standard modes. This patch creates the macro _LIBCPP_HAS_IS_FINAL to note the availability of `__is_final`.
Reviewers: danalbert, mclow.lists
Reviewed By: mclow.lists
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D8795
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@239664 91177308-0d34-0410-b5e6-96231b3b80d8
Things done in this patch:
1. Make __debug include __config since it uses macros from it.
2. The current method of defining _LIBCPP_ASSERT is prone to redefinitions. Move
the null _LIBCPP_ASSERT definition into the __debug header to prevent this.
3. Remove external <__debug> include gaurds. <__debug> guards almost all of its
contents internally. There is no reason to be doing it externally.
This patch should not change any functionality.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@215332 91177308-0d34-0410-b5e6-96231b3b80d8
unordered_set, however it is not complete yet for unordered_multiset,
unordered_map or unordered_multimap. There has been a lot of work done
for these other three containers, however that work was done just to
keep all of the tests passing.
You can try this out with -D_LIBCPP_DEBUG2. You will have to link to a
libc++.dylib that has been compiled with src/debug.cpp. So far, vector
(but not vector<bool>), list, and unordered_set are treated. I hope to
get the other three unordered containers up fairly quickly now that
unordered_set is done.
The flag _LIBCPP_DEBUG2 will eventually be changed to _LIBCPP_DEBUG, but
not today. This is my second effort at getting debug mode going for
libc++, and I'm not quite yet ready to throw all of the work under the
first attempt away.
The basic design is that all of the debug information is kept in a
central database, instead of in the containers. This has been done as
an attempt to have debug mode and non-debug mode be ABI compatible with
each other. There are some circumstances where if you construct a
container in an environment without debug mode and pass it into debug
mode, the checking will get confused and let you know with a readable
error message. Passing containers the other way: from debug mode out to
a non-debugging mode container should be 100% safe (at least that is the
goal).
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@186991 91177308-0d34-0410-b5e6-96231b3b80d8
