The __atomic_base base class is only useful to conditionalize the
operations we provide inside std::atomic. It shouldn't be used directly
from other places in the library which can use std::atomic directly
instead.
Since we've granularized our includes, using std::atomic directly should
not make much of a difference compile-time wise.
This patch starts using std::atomic directly from other classes like
std::barrier and std::latch. Changing this shouldn't be an ABI break
since both classes have the same size and layout.
The benefits of this patch are isolating other parts of the code base
from implementation details of std::atomic and simplifying the mental
model for std::atomic's layers of implementation by making it clear that
__atomic_base is only an implementation detail of std::atomic.
This addresses the issue uncovered by #115361. Previously, we weren't
building benchmarks in many cases due to the following block:
e58949632e/libcxx/CMakeLists.txt (L162-L172)
We need to passthrough the necessary variables into the benchmarks
subbuild and use correct syntax.
In particular, test everything with both a normal and a min_allocator,
add tests for a few corner cases and add tests with types that are
trivially relocatable. Also add tests that count the number of
assignments performed by vector::erase, since that is mandated by the
Standard.
This patch is a preparation for optimizing vector::erase.
The input generating functions for benchmark tests in the GenerateInput.h
file can be slightly improved by invoking vector::reserve before calling
vector::push_back. This slight performance improvement could potentially
speed-up all benchmark tests for containers and algorithms that use these
functions as inputs.
Now that we don't use __compressed_pair anymore inside std::vector, we
can remove some unnecessary accessors. This is a mechanical replacement
of the __alloc() and __end_cap() accessors, and similar for
std::vector<bool>.
Note that I consistently used this->__alloc_ instead of just __alloc_
since most of the code in <vector> uses that pattern to access members.
I don't think this is necessary anymore (and I'm even less certain I
like this), but I went for consistency with surrounding code. If we want
to change that, we can do a follow-up mechanical change.
After a recent Github Actions runner policy change [1], the version of
Xcode included in the macos-14 image went from Xcode 16 to Xcode 15,
breaking our build bots.
This moves the bots to the macos 15 (public preview) image, which
contains Xcode 16.
Also, adjust an UNSUPPORTED annotation that was incorrectly targeting
macos 13.7 when it should have been targeting a version of AppleClang.
[1]: https://github.com/actions/runner-images/issues/10703
This moves the configuration of the CMake features to turn off RTTI,
exceptions and friends to the beginning of the CMake file, where we
configure other optional parts of the library.
This fixes an important bug where we would disable the benchmarks
because these options were not defined yet, leading to the build
thinking they were defined to OFF.
This generalizes the algorithm a bit. Unfortunately, we can't make
the call sites cleaner inside std::vector because the arguments being
passed can all be fancy pointers, which may not be contiguous iterators.
`__shared_count` is used in a few places where `shared_ptr` isn't. This
avoids a bunch of transitive includes needed for the implementation of
`shared_ptr` in these places.
The variables are all `constexpr`, which implies `inline`. Since they
aren't `constexpr` in C++03 they're also not `inline` there. Because of
that we define them out-of-line currently. Instead we can use the C++17
extension of `inline` variables, which results in the same weak
definitions of the variables but without having all the boilerplate.
Related to PR #114423, this PR proposes to unify the naming of the
internal pointer members in `std::vector` and `std::__split_buffer` for
consistency and clarity.
Both `std::vector` and `std::__split_buffer` originally used a
`__compressed_pair<pointer, allocator_type>` member named `__end_cap_`
to store an internal capacity pointer and an allocator. However,
inconsistent naming changes have been made in both classes:
- `std::vector` now uses `__cap_` and `__alloc_` for its internal
pointer and allocator members.
- In contrast, `std::__split_buffer` retains the name `__end_cap_` for
the capacity pointer, along with `__alloc_`.
This inconsistency between the names `__cap_` and `__end_cap_` has
caused confusions (especially to myself when I was working on both
classes). I suggest unifying these names by renaming `__end_cap_` to
`__cap_` in `std::__split_buffer`.
`std::copy` doesn't use the `_AlgPolicy` for anything other than calling
itself with it, so we can just remove the argument. This also removes
the need in a few other algorithms which had an `_AlgPolicy` argument
only to call `copy`.
This introduces a new `__scope_guard` without any fancy features. The
scope guard is used in `<string>` to simplify some of the ASan
annotations (especially by making it harder to forget them where
exceptions are thrown).
Instead of going through the old locale entry points, define the base
localization API for BSD-like platforms (Apple and FreeBSD) from
scratch, using <xlocale.h> as a basis. This doesn't actually change how
that functionality is implemented, it only avoids going through a maze
to do so.
This clean new support is implemented in a separate __locale_dir/support
directory, which mirrors what we do for the threading support API.
Eventually, everything under __locale_dir/locale_base_api will go away.
rdar://131476632
Currently `string::shrink_to_fit()` throws away any allocations which
return more capacity than we requested, even if that allocation is still
smaller than the current capacity. This patch fixes this to compare the
returned allocation against the current capacity of the string instead
of against the requested capacity.
This PR restricts construction to cases where reference types of
source/destination iterators are (`T&`, `T&`) or (`T&`, `const T&`) (
where `T` can be const).
Fixes#50058.
This PR refines the code in `GenerateInput.h` used for benchmark testing
by implementing the following changes:
- Replaced all unqualified usages of `size_t` with `std::size_t`.
- Removed unnecessary curly braces `{}` from for loops that contain
simple single-statement bodies, in accordance with LLVM coding
standards.
This script does not depend on the generated headers since those are
already special-cased in header_information.py. Change the dependency
list to depend on header_information.py instead. While looking at this
code also simplify the assignment to libcxx_root inside this script.
We can't `static_assert` `__libcpp_is_contiguous_iterator` for
`__wrap_iter` currently because `__wrap_iter` is also used for wrapping
user-defined fancy pointers.
Fixes#115002.
Rewriting `__alloc()` and `__dealloc()` template functions to avoid errors when `small_buffer.h` is
included in the modules LIT tests. For example:
```
test-suite-install/include/c++/v1/__utility/small_buffer.h:69:81: error: use of undeclared identifier 'align_val_t'
# | 69 | byte* __allocation = static_cast<byte*>(::operator new[](sizeof(_Stored), align_val_t{alignof(_Stored)}));
# | | ^
```
Currently, libc++ incorrectly rejects heterogeneous comparison of
`unexpected`, because the `operator==` is only a hidden friend of
`unexpected<_Err>` but not of `unexpected<_Err2>`. We need to call the
`error()` member function on `__y`.
Fixes#115326
This patch introduces a new kind of bounded iterator that knows the size
of its valid range at compile-time, as in std::array. This allows computing
the end of the range from the start of the range and the size, which requires
storing only the start of the range in the iterator instead of both the start
and the size (or start and end). The iterator wrapper is otherwise identical
in design to the existing __bounded_iter.
Since this requires changing the type of the iterators returned by
std::array, this new bounded iterator is controlled by an ABI flag.
As a drive-by, centralize the tests for std::array::operator[] and add
missing tests for OOB operator[] on non-empty arrays.
Fixes#70864
Instead of building the benchmarks separately via CMake and running them
separately from the test suite, this patch merges the benchmarks into
the test suite and handles both uniformly.
As a result:
- It is now possible to run individual benchmarks like we run tests
(e.g. using libcxx-lit), which is a huge quality-of-life improvement.
- The benchmarks will be run under exactly the same configuration as
the rest of the tests, which is a nice simplification. This does
mean that one has to be careful to enable the desired optimization
flags when running benchmarks, but that is easy with e.g.
`libcxx-lit <...> --param optimization=speed`.
- Benchmarks can use the same annotations as the rest of the test
suite, such as `// UNSUPPORTED` & friends.
When running the tests via `check-cxx`, we only compile the benchmarks
because running them would be too time consuming. This introduces a bit
of complexity in the testing setup, and instead it would be better to
allow passing a --dry-run flag to GoogleBenchmark executables, which is
the topic of https://github.com/google/benchmark/issues/1827.
I am not really satisfied with the layering violation of adding the
%{benchmark_flags} substitution to cmake-bridge, however I believe
this can be improved in the future.
