Summary:
Hi,
When creating a new thread libc++ performs at least 2 allocations. The first allocates a tuple of args and the functor that will be passed to the new thread. The second allocation is for the thread local storage needed internally by libc++. Currently the second allocation happens in the child thread, meaning that if it throws the program will terminate with an uncaught bad alloc.
The solution to this is to allocate ALL memory in the parent thread and then pass it to the child.
See https://llvm.org/bugs/show_bug.cgi?id=15638
Reviewers: mclow.lists, danalbert, jroelofs, EricWF
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D13748
llvm-svn: 266851
The primary purpose of this patch is to add the 'is_callable' traits.
Since 'is_nothrow_callable' required making 'INVOKE' conditionally noexcept
I also took this oppertunity to implement a constexpr version of INVOKE.
This fixes 'std::experimental::apply' which required constexpr 'INVOKE support'.
This patch will be followed up with some cleanup. Primarly removing most
of "__member_function_traits" since it's no longer used by INVOKE (in C++11 at least).
llvm-svn: 266836
In cases where emplace is called with two arguments and the first one
matches the key_type we can Key to check for duplicates before allocating.
This patch expands on work done by dexonsmith@apple.com.
llvm-svn: 266498
There are two main fixes in this patch.
First the constructor SFINAE was changed so that it's evaluated in two stages
where the first stage evaluates the "safe" SFINAE conditions and the second
evaluates the "dangerous" ones. The key is that the second stage is lazily
evaluated only if the first stage passes. This helps fix PR23256
(https://llvm.org/bugs/show_bug.cgi?id=23256).
The second fix is for PR22806 and LWG issue 2549. This fix applies
the suggested resolution to the LWG issue in order to prevent the construction
of dangling references. The SFINAE for this check is contained within
the _PreferTupleLikeConstructor alias template. The tuple-like constructors
are disabled whenever that trait returns false.
(https://llvm.org/bugs/show_bug.cgi?id=22806)
(http://cplusplus.github.io/LWG/lwg-active.html#2549)
llvm-svn: 266461
Summary:
A default uses-allocator constructor has been added since that overload was previously provided by the extended constructor.
Since Clang does implicit conversion checking after substitution this constructor has to deduce the allocator_arg_t parameter so that it can prevent the evaluation of "is_default_constructible" if the first argument doesn't match. See http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#1391 for more information.
This patch fixes PR24779 (https://llvm.org/bugs/show_bug.cgi?id=24779)
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D19006
llvm-svn: 266409
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
This patch is fairly large and contains a number of changes. The changes all work towards
allowing __tree to properly handle __value_type esspecially when inserting into the __tree.
I chose not to break this change into smaller patches because it wouldn't be possible to
write meaningful standard-compliant tests for each patch.
It is very similar to r260513 "[libcxx] Teach __hash_table how to handle unordered_map's __hash_value_type".
Changes in <map>
* Remove __value_type's constructors because it should never be constructed directly.
* Make map::emplace and multimap::emplace forward to __tree and remove the old definitions
* Remove "__construct_node" map and multimap member functions. Almost all of the construction is done within __tree.
* Fix map's move constructor to access "__value_type.__nc" directly and pass this object to __tree::insert.
Changes in <__tree>
* Add traits to detect, handle, and unwrap, map's "__value_type".
* Convert methods taking "value_type" to take "__container_value_type" instead. Previously these methods caused
unwanted implicit conversions from "std::pair<Key, Value>" to "__value_type<Key, Value>".
* Delete __tree_node and __tree_node_base's constructors and assignment operators. The node types should never be constructed
because the "__value_" member of __tree_node must be constructed directly by the allocator.
* Make the __tree_node_destructor class and "__construct_node" methods unwrap "__node_value_type" into "__container_value_type" before invoking the allocator. The user's allocator can only be used to construct and destroy the container's value_type. Passing it map's "__value_type" was incorrect.
* Cleanup the "__insert" and "__emplace" methods. Have __insert forward to an __emplace function wherever possible to reduce
code duplication. __insert_unique(value_type const&) and __insert_unique(value_type&&) forward to __emplace_unique_key_args.
These functions will not allocate a new node if the value is already in the tree.
* Change the __find* functions to take the "key_type" directly instead of passing in "value_type" and unwrapping the key later.
This change allows the find functions to be used without having to construct a "value_type" first. This allows for a number
of optimizations.
* Teach __move_assign and __assign_multi methods to unwrap map's __value_type.
llvm-svn: 264986
Summary:
This was voted into C++17 at the Jacksonville meeting. The final P0152R1
paper will be in the upcoming post-Jacksonville mailing, and is also
available here:
http://jfbastien.github.io/papers/P0152R1.html
Reviewers: mclow.lists, rsmith
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D17951
llvm-svn: 264413
unordered_set::emplace and unordered_map::emplace construct a node, then
try to insert it. If insertion fails, the node gets deleted.
To avoid this unnecessary malloc traffic, check to see if the argument
to emplace has the appropriate key_type. If so, we can use that key
directly and delay the malloc until we're sure we're inserting something
new.
Test updates by Eric Fiselier, who rewrote the old allocation tests to
include the new cases.
There are two orthogonal future directions:
1. Apply the same optimization to set and map.
2. Extend the optimization to when the argument is not key_type, but can
be converted to it without side effects. Ideally, we could do this
whenever key_type is trivially destructible and the argument is
trivially convertible to key_type, but in practise the relevant type
traits "blow up sometimes". At least, we should catch a few simple
cases (such as when both are primitive types).
llvm-svn: 263746
Commit f49839299a085505eb673544744b61d2d9cdd1db in glibc-2.14 changed the
locales to the currently required format. However, they were again changed in
commit 55bdd2866f23b28422d969060b3518909a12b100 which has been released in 2.17.
That leads to the current situation where Debian and e.g. CentOS 6 have the
pre-2.14 locales, for example Ubuntu 14.04 has pre-2.17 and CentOS 7 on the
other hand has the newest locales in glibc-2.17.
Differential Revision: http://reviews.llvm.org/D18187
llvm-svn: 263554
