This patch further decouples libc++ from pthread, allowing libc++ to be built
against other threading systems. There are two main use cases:
- Building libc++ against a thread library other than pthreads.
- Building libc++ with an "external" thread API, allowing a separate library to
provide the implementation of that API.
The two use cases are quite similar, the second one being sligtly more
de-coupled than the first. The cmake option LIBCXX_HAS_EXTERNAL_THREAD_API
enables both kinds of builds. One needs to place an <__external_threading>
header file containing an implementation of the "libc++ thread API" declared
in the <__threading_support> header.
For the second use case, the implementation of the libc++ thread API can
delegate to a custom "external" thread API where the implementation of this
external API is provided in a seperate library. This mechanism allows toolchain
vendors to distribute a build of libc++ with a custom thread-porting-layer API
(which is the "external" API above), platform vendors (recipients of the
toolchain/libc++) are then required to provide their implementation of this API
to be linked with (end-user) C++ programs.
Note that the second use case still requires establishing the basic types that
get passed between the external thread library and the libc++ library
(e.g. __libcpp_mutex_t). These cannot be opaque pointer types (libc++ sources
won't compile otherwise). It should also be noted that the second use case can
have a slight performance penalty; as all the thread constructs need to cross a
library boundary through an additional function call.
When the header <__external_threading> is omitted, libc++ is built with the
"libc++ thread API" (declared in <__threading_support>) as the "external" thread
API (basic types are pthread based). An implementation (pthread based) of this
API is provided in test/support/external_threads.cpp, which is built into a
separate DSO and linked in when running the libc++ test suite. A test run
therefore demonstrates the second use case (less the intermediate custom API).
Differential revision: https://reviews.llvm.org/D21968
Reviewers: bcraig, compnerd, EricWF, mclow.lists
llvm-svn: 281179
This patch fixes PR30260 by using a (void*) cast on the placement argument
to placement new to casts away the const. See also http://llvm.org/PR30260.
As a drive by change this patch also changes the header guard for
<experimental/optional> to _LIBCPP_EXPERIMENTAL_OPTIONAL from _LIBCPP_OPTIONAL.
llvm-svn: 280775
Summary:
This patch allows threads not created using `std::thread` to use `std::notify_all_at_thread_exit` by ensuring the TL state has been initialized within `std::notify_all_at_thread_exit`.
Additionally this patch "fixes" a potential oddity in `__thread_local_pointer::reset(pointer)`, which would previously delete the old thread local data. However there should *never* be old thread local data because pthread *should* null it out on thread exit. Unfortunately it's possible that pthread failed to do this according to the spec:
>
> Upon key creation, the value NULL shall be associated with the new key in all active threads. Upon thread creation, the value NULL shall be associated with all defined keys in the new thread.
>
> An optional destructor function may be associated with each key value. At thread exit, if a key value has a non-NULL destructor pointer, and the thread has a non-NULL value associated with that key, the value of the key is set to NULL, and then the function pointed to is called with the previously associated value as its sole argument. The order of destructor calls is unspecified if more than one destructor exists for a thread when it exits.
>
> If, after all the destructors have been called for all non-NULL values with associated destructors, there are still some non-NULL values with associated destructors, then the process is repeated. If, after at least {PTHREAD_DESTRUCTOR_ITERATIONS} iterations of destructor calls for outstanding non-NULL values, there are still some non-NULL values with associated destructors, implementations may stop calling destructors, or they may continue calling destructors until no non-NULL values with associated destructors exist, even though this might result in an infinite loop.
However if pthread fails to delete the value it is probably incorrect for us to do it. Destroying the value performs all of the "at thread exit" actions registered with it but we are way past "at thread exit".
Reviewers: mclow.lists, bcraig, EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24159
llvm-svn: 280588
Some of the mutex tests fail on machines with high load. This patch implements
the test directive "// FLAKY_TEST" which allows a test to be run 3 times
before it's considered a failure.
llvm-svn: 280050
This assignment operator was previously broken since the SFINAE always resulted
in substitution failure. This caused assignments to turn into
copy construction + assignment.
This patch was originally committed as r279953 but was reverted due to warnings
in the test-suite. This new patch corrects those warnings.
llvm-svn: 279955
This assignment operator was previously broken since the SFINAE always resulted
in substitution failure. This caused assignments to turn into
copy construction + assignment.
llvm-svn: 279953
This patch implements the std::sample function added to C++17 from LFTS. It
also removes the std::experimental::sample implementation which now forwards
to std::sample.
llvm-svn: 279948
Libc++'s implementation of shuffle and sample already support lvalue and rvalue
RNG's. This patch adds tests for both categories and marks the issue as complete.
This patch also contains drive-by change for std::experimental::sample which
improves the diagnostics produced when the correct iterator categories are
not supplied.
llvm-svn: 279947
Summary:
The point of this patch is to have a consistent convention for naming build, check and install targets so that the targets can be constructed from the project name.
This change renames a bunch of CMake components and targets from libcxx to cxx. For each renamed target I've added a convenience target that matches the old target name and depends on the new target. This will preserve function of the old targets so that the change doesn't break the world. We can evaluate if it is worth removing the extra targets later.
Reviewers: EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D23699
llvm-svn: 279675
Some tests uses 'long double' to/from conversions and for some targets
they are provided by compiler runtime (either compiler-rt or libgcc).
However when building libcxx with linunwinder current test configuration
at target_info.py do not include the required libraries, as:
not llvm_unwinder:
"-lc++" "-lm" "-lgcc_s" "-lgcc" "-lpthread" "-lc" "-lgcc_s" "-lgcc"
llvm_unwinder
"-lc++" "-lm" "-lpthread" "-lc" "-lunwind" "-ldl"
This causes some tests build issues with missing symbols on aarch64,
for instance, where 'long double' is a binary float with 128-bits with
mostly of internal operations being provided by software routines.
This patch changes how to define the default linker flags with libunwinder by
adding libgcc regardless.
I checked and aarch64 and x86_64 with libcxx and libunwind (with and without
LIBCXXABI_USE_LLVM_UNWINDER).
llvm-svn: 279552
Summary:
The new LLVM runtimes build directory requires some basic conventions across the runtime projects. These changes make libcxx build under the runtimes subdirectory. The general idea of the changes is that the runtimes subdirectory requires some conventions to be consistent across runtime projects.
I expect to have a few more small patches that build on this to tie up check targets and other things useful in development workflows.
Summary of changes in this patch:
* Renamed variable LLVM_CONFIG -> LLVM_CONFIG_PATH
* Renamed variable LIBCXX_BUILT_STANDALONE -> LIBCXX_STANDALONE_BUILD
* Add an include of AddLLVM in the tests subdirectory for add_lit_testsuite.
Reviewers: EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D23696
llvm-svn: 279151
The expected 'filesystem::path::compare' result states that for different
path only result sign contains the information about passed arguments
(not its integer value). This is due it uses the output of other compare
functions (basic_string_view and char_traits) without further handling and
char_traits uses memcmp for final buffer comparison.
However for GLIBC on AArch64 the code:
int ret = memcmp ("b/a/c", "a/b/c", 1);
Results in '64' where for x86_64 it results in '1'.
This patch fixes the expected 'filesystem::path::compare' by normalizing
all the results before assert comparison.
llvm-svn: 278745
Currently certain tests get killed when compiled with ASAN at -O0 because
they eat all of the systems memory. This doesn't happen at -O1, so enable that
to work around the issue.
llvm-svn: 278722
Some filesystems track atime always. This relaxes the test to accept either a
filesystem which does not accurately track atime or does track the atime
accurately. This allows the test to pass on filesystems mounted with
`strictatime` on Linux or on macOS.
llvm-svn: 278357
Summary:
The synopsis in C++11 subclause 28.8 [re.regex] has:
```
basic_regex(const charT* p, size_t len,
flag_type f = regex_constants::ECMAScript);
```
The default argument is added to libc++ by this change.
Reviewers: mclow.lists, rsmith, hubert.reinterpretcast
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D22702
Reapplies r277966.
Patch by Jason Liu!
llvm-svn: 277968
Summary:
In the synopsis in C++11 subclause 28.8 [re.regex], `basic_regex` is
specified to have member typedefs `traits_type` and `string_type`. This
change adds them to libc++.
Reviewers: mclow.lists, rsmith, hubert.reinterpretcast
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D22698
Patch by Jason Liu!
llvm-svn: 277526
It currently fails because GCC changed the mangling of templates, which affects std::atomic using __attribute__((vector(X))). The bot using GCC 4.9 generates the following message:
In file included from /home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/test/libcxx/atomics/atomics.align/align.pass.sh.cpp:24:0:
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/include/atomic: In instantiation of 'atomic_test<T>::atomic_test() [with T = __vector(2) int]':
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/test/libcxx/atomics/atomics.align/align.pass.sh.cpp:66:3: required from here
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/include/atomic:583:5: error: 'std::__1::__gcc_atomic::__gcc_atomic_t<_Tp>::__gcc_atomic_t() [with _Tp = __vector(2) int]' conflicts with a previous declaration
__gcc_atomic_t() _NOEXCEPT = default;
^
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/include/atomic:583:5: note: previous declaration 'std::__1::__gcc_atomic::__gcc_atomic_t<_Tp>::__gcc_atomic_t() [with _Tp = __vector(1) int]'
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/include/atomic:583:5: note: -fabi-version=6 (or =0) avoids this error with a change in mangling
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/include/atomic:583:5: error: 'std::__1::__gcc_atomic::__gcc_atomic_t<_Tp>::__gcc_atomic_t() [with _Tp = __vector(2) int]' conflicts with a previous declaration
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/include/atomic:583:5: note: previous declaration 'std::__1::__gcc_atomic::__gcc_atomic_t<_Tp>::__gcc_atomic_t() [with _Tp = __vector(1) int]'
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/include/atomic:583:5: note: -fabi-version=6 (or =0) avoids this error with a change in mangling
/home/llvm-builder/llvm-buildslave-root/libcxx-libcxxabi-x86_64-linux-ubuntu-gcc49-cxx11/llvm/projects/libcxx/include/atomic:939:5: note: synthesized method 'std::__1::__gcc_atomic::__gcc_atomic_t<_Tp>::__gcc_atomic_t() [with _Tp = __vector(2) int]' first required here
__atomic_base() _NOEXCEPT = default;
^
GCC's docs say the following about ABI version 6:
Version 6, which first appeared in G++ 4.7, corrects the promotion behavior of C++11 scoped enums and the mangling of template argument packs, const/static_cast, prefix ++ and –, and a class scope function used as a template argument.
llvm-svn: 277380
Summary:
libc++ implements std::atomic<_Tp> using __atomic_base<_Tp> with
`mutable _Atomic(_Tp) __a_`. That member must be suitably aligned on
relevant ISAs for instructions such as cmpxchg to work properly, but
this alignment isn't checked anywhere. __atomic_base's implementation
relies on _Atomic doing "the right thing" since it's under the
compiler's control, and only the compiler knows about lock-freedom and
instruction generation. This test makes sure that the compiler isn't
breaking libc++'s expectations.
I'm looking at a few odd things in the C++ standard, and will have a few
other fixes around this area in the future.
This requires building with `-DLIBCXX_HAS_ATOMIC_LIB=True`, the test
marks the dependency as REQUIRES and won't be run without.
Reviewers: cfe-commits
Subscribers: EricWF, mclow.lists
Differential Revision: http://reviews.llvm.org/D22073
llvm-svn: 277368
Asiri Rathnayake