Coverage Report

Created: 2020-02-25 14:32

/Users/buildslave/jenkins/workspace/coverage/llvm-project/libcxx/include/thread
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// -*- C++ -*-
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//===--------------------------- thread -----------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef _LIBCPP_THREAD
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#define _LIBCPP_THREAD
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/*
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    thread synopsis
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namespace std
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{
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class thread
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{
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public:
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    class id;
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    typedef pthread_t native_handle_type;
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    thread() noexcept;
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    template <class F, class ...Args> explicit thread(F&& f, Args&&... args);
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    ~thread();
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    thread(const thread&) = delete;
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    thread(thread&& t) noexcept;
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    thread& operator=(const thread&) = delete;
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    thread& operator=(thread&& t) noexcept;
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    void swap(thread& t) noexcept;
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    bool joinable() const noexcept;
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    void join();
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    void detach();
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    id get_id() const noexcept;
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    native_handle_type native_handle();
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    static unsigned hardware_concurrency() noexcept;
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};
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void swap(thread& x, thread& y) noexcept;
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class thread::id
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{
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public:
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    id() noexcept;
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};
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bool operator==(thread::id x, thread::id y) noexcept;
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bool operator!=(thread::id x, thread::id y) noexcept;
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bool operator< (thread::id x, thread::id y) noexcept;
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bool operator<=(thread::id x, thread::id y) noexcept;
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bool operator> (thread::id x, thread::id y) noexcept;
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bool operator>=(thread::id x, thread::id y) noexcept;
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template<class charT, class traits>
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basic_ostream<charT, traits>&
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operator<<(basic_ostream<charT, traits>& out, thread::id id);
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namespace this_thread
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{
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thread::id get_id() noexcept;
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void yield() noexcept;
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template <class Clock, class Duration>
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void sleep_until(const chrono::time_point<Clock, Duration>& abs_time);
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template <class Rep, class Period>
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void sleep_for(const chrono::duration<Rep, Period>& rel_time);
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}  // this_thread
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}  // std
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*/
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#include <__config>
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#include <iosfwd>
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#include <__functional_base>
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#include <type_traits>
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#include <cstddef>
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#include <functional>
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#include <memory>
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#include <system_error>
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#include <chrono>
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#include <__mutex_base>
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#ifndef _LIBCPP_CXX03_LANG
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#include <tuple>
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#endif
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#include <__threading_support>
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#include <__debug>
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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
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#pragma GCC system_header
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#endif
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_LIBCPP_PUSH_MACROS
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#include <__undef_macros>
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#ifdef _LIBCPP_HAS_NO_THREADS
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#error <thread> is not supported on this single threaded system
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#else // !_LIBCPP_HAS_NO_THREADS
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_LIBCPP_BEGIN_NAMESPACE_STD
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template <class _Tp> class __thread_specific_ptr;
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class _LIBCPP_TYPE_VIS __thread_struct;
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class _LIBCPP_HIDDEN __thread_struct_imp;
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class __assoc_sub_state;
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_LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data();
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class _LIBCPP_TYPE_VIS __thread_struct
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{
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    __thread_struct_imp* __p_;
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    __thread_struct(const __thread_struct&);
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    __thread_struct& operator=(const __thread_struct&);
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public:
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    __thread_struct();
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    ~__thread_struct();
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    void notify_all_at_thread_exit(condition_variable*, mutex*);
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    void __make_ready_at_thread_exit(__assoc_sub_state*);
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};
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template <class _Tp>
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class __thread_specific_ptr
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{
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    __libcpp_tls_key __key_;
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     // Only __thread_local_data() may construct a __thread_specific_ptr
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     // and only with _Tp == __thread_struct.
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    static_assert((is_same<_Tp, __thread_struct>::value), "");
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    __thread_specific_ptr();
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    friend _LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data();
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    __thread_specific_ptr(const __thread_specific_ptr&);
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    __thread_specific_ptr& operator=(const __thread_specific_ptr&);
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    _LIBCPP_HIDDEN static void _LIBCPP_TLS_DESTRUCTOR_CC __at_thread_exit(void*);
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public:
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    typedef _Tp* pointer;
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    ~__thread_specific_ptr();
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    _LIBCPP_INLINE_VISIBILITY
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    pointer get() const {return static_cast<_Tp*>(__libcpp_tls_get(__key_));}
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    _LIBCPP_INLINE_VISIBILITY
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    pointer operator*() const {return *get();}
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    _LIBCPP_INLINE_VISIBILITY
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    pointer operator->() const {return get();}
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    void set_pointer(pointer __p);
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};
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template <class _Tp>
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void _LIBCPP_TLS_DESTRUCTOR_CC
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__thread_specific_ptr<_Tp>::__at_thread_exit(void* __p)
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{
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    delete static_cast<pointer>(__p);
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}
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template <class _Tp>
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__thread_specific_ptr<_Tp>::__thread_specific_ptr()
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{
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  int __ec =
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      __libcpp_tls_create(&__key_, &__thread_specific_ptr::__at_thread_exit);
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  if (__ec)
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    __throw_system_error(__ec, "__thread_specific_ptr construction failed");
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}
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template <class _Tp>
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__thread_specific_ptr<_Tp>::~__thread_specific_ptr()
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{
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    // __thread_specific_ptr is only created with a static storage duration
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    // so this destructor is only invoked during program termination. Invoking
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    // pthread_key_delete(__key_) may prevent other threads from deleting their
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    // thread local data. For this reason we leak the key.
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}
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template <class _Tp>
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void
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__thread_specific_ptr<_Tp>::set_pointer(pointer __p)
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{
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    _LIBCPP_ASSERT(get() == nullptr,
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                   "Attempting to overwrite thread local data");
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    __libcpp_tls_set(__key_, __p);
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}
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template<>
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struct _LIBCPP_TEMPLATE_VIS hash<__thread_id>
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    : public unary_function<__thread_id, size_t>
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{
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    _LIBCPP_INLINE_VISIBILITY
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    size_t operator()(__thread_id __v) const _NOEXCEPT
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    {
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        return hash<__libcpp_thread_id>()(__v.__id_);
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    }
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};
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template<class _CharT, class _Traits>
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_LIBCPP_INLINE_VISIBILITY
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basic_ostream<_CharT, _Traits>&
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operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id)
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{return __os << __id.__id_;}
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class _LIBCPP_TYPE_VIS thread
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{
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    __libcpp_thread_t __t_;
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    thread(const thread&);
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    thread& operator=(const thread&);
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public:
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    typedef __thread_id id;
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    typedef __libcpp_thread_t native_handle_type;
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    _LIBCPP_INLINE_VISIBILITY
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    thread() _NOEXCEPT : __t_(_LIBCPP_NULL_THREAD) {}
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#ifndef _LIBCPP_CXX03_LANG
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    template <class _Fp, class ..._Args,
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              class = typename enable_if
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              <
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                   !is_same<typename __uncvref<_Fp>::type, thread>::value
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              >::type
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             >
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        _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
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        explicit thread(_Fp&& __f, _Args&&... __args);
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#else  // _LIBCPP_CXX03_LANG
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    template <class _Fp>
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    _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
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    explicit thread(_Fp __f);
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#endif
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    ~thread();
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#ifndef _LIBCPP_CXX03_LANG
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    _LIBCPP_INLINE_VISIBILITY
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    thread(thread&& __t) _NOEXCEPT : __t_(__t.__t_) {__t.__t_ = _LIBCPP_NULL_THREAD;}
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    _LIBCPP_INLINE_VISIBILITY
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    thread& operator=(thread&& __t) _NOEXCEPT;
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#endif  // _LIBCPP_CXX03_LANG
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    _LIBCPP_INLINE_VISIBILITY
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    void swap(thread& __t) _NOEXCEPT {_VSTD::swap(__t_, __t.__t_);}
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    _LIBCPP_INLINE_VISIBILITY
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    bool joinable() const _NOEXCEPT {return !__libcpp_thread_isnull(&__t_);}
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    void join();
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    void detach();
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    _LIBCPP_INLINE_VISIBILITY
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    id get_id() const _NOEXCEPT {return __libcpp_thread_get_id(&__t_);}
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    _LIBCPP_INLINE_VISIBILITY
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    native_handle_type native_handle() _NOEXCEPT {return __t_;}
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    static unsigned hardware_concurrency() _NOEXCEPT;
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};
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#ifndef _LIBCPP_CXX03_LANG
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template <class _TSp, class _Fp, class ..._Args, size_t ..._Indices>
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inline _LIBCPP_INLINE_VISIBILITY
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void
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__thread_execute(tuple<_TSp, _Fp, _Args...>& __t, __tuple_indices<_Indices...>)
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{
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    __invoke(_VSTD::move(_VSTD::get<1>(__t)), _VSTD::move(_VSTD::get<_Indices>(__t))...);
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}
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template <class _Fp>
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_LIBCPP_INLINE_VISIBILITY
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void* __thread_proxy(void* __vp)
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{
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    // _Fp = std::tuple< unique_ptr<__thread_struct>, Functor, Args...>
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    std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
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    __thread_local_data().set_pointer(_VSTD::get<0>(*__p).release());
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    typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 2>::type _Index;
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    __thread_execute(*__p, _Index());
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    return nullptr;
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}
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template <class _Fp, class ..._Args,
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          class
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         >
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thread::thread(_Fp&& __f, _Args&&... __args)
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{
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    typedef unique_ptr<__thread_struct> _TSPtr;
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    _TSPtr __tsp(new __thread_struct);
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    typedef tuple<_TSPtr, typename decay<_Fp>::type, typename decay<_Args>::type...> _Gp;
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    _VSTD::unique_ptr<_Gp> __p(
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            new _Gp(std::move(__tsp),
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                    __decay_copy(_VSTD::forward<_Fp>(__f)),
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                    __decay_copy(_VSTD::forward<_Args>(__args))...));
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    int __ec = __libcpp_thread_create(&__t_, &__thread_proxy<_Gp>, __p.get());
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    if (__ec == 0)
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        __p.release();
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    else
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        __throw_system_error(__ec, "thread constructor failed");
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}
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inline
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thread&
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thread::operator=(thread&& __t) _NOEXCEPT
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{
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    if (!__libcpp_thread_isnull(&__t_))
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        terminate();
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    __t_ = __t.__t_;
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    __t.__t_ = _LIBCPP_NULL_THREAD;
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    return *this;
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}
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#else  // _LIBCPP_CXX03_LANG
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template <class _Fp>
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struct __thread_invoke_pair {
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    // This type is used to pass memory for thread local storage and a functor
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    // to a newly created thread because std::pair doesn't work with
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    // std::unique_ptr in C++03.
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    __thread_invoke_pair(_Fp& __f) : __tsp_(new __thread_struct), __fn_(__f) {}
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    unique_ptr<__thread_struct> __tsp_;
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    _Fp __fn_;
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};
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template <class _Fp>
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void* __thread_proxy_cxx03(void* __vp)
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{
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    std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));
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    __thread_local_data().set_pointer(__p->__tsp_.release());
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    (__p->__fn_)();
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    return nullptr;
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}
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template <class _Fp>
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thread::thread(_Fp __f)
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{
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    typedef __thread_invoke_pair<_Fp> _InvokePair;
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    typedef std::unique_ptr<_InvokePair> _PairPtr;
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    _PairPtr __pp(new _InvokePair(__f));
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    int __ec = __libcpp_thread_create(&__t_, &__thread_proxy_cxx03<_InvokePair>, __pp.get());
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    if (__ec == 0)
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        __pp.release();
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    else
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        __throw_system_error(__ec, "thread constructor failed");
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}
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#endif  // _LIBCPP_CXX03_LANG
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inline _LIBCPP_INLINE_VISIBILITY
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void swap(thread& __x, thread& __y) _NOEXCEPT {__x.swap(__y);}
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namespace this_thread
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{
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_LIBCPP_FUNC_VIS void sleep_for(const chrono::nanoseconds& __ns);
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template <class _Rep, class _Period>
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void
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sleep_for(const chrono::duration<_Rep, _Period>& __d)
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{
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    using namespace chrono;
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    if (__d > duration<_Rep, _Period>::zero())
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    {
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#if defined(_LIBCPP_COMPILER_GCC) && (__powerpc__ || __POWERPC__)
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    //  GCC's long double const folding is incomplete for IBM128 long doubles.
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        _LIBCPP_CONSTEXPR duration<long double> _Max = nanoseconds::max();
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#else
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        _LIBCPP_CONSTEXPR duration<long double> _Max = duration<long double>(ULLONG_MAX/1000000000ULL) ;
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#endif
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        nanoseconds __ns;
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        if (__d < _Max)
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        {
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            __ns = duration_cast<nanoseconds>(__d);
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            if (__ns < __d)
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                ++__ns;
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        }
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        else
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            __ns = nanoseconds::max();
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        sleep_for(__ns);
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    }
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}
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template <class _Clock, class _Duration>
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void
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sleep_until(const chrono::time_point<_Clock, _Duration>& __t)
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{
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    using namespace chrono;
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    mutex __mut;
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    condition_variable __cv;
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    unique_lock<mutex> __lk(__mut);
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    while (_Clock::now() < __t)
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        __cv.wait_until(__lk, __t);
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}
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template <class _Duration>
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inline _LIBCPP_INLINE_VISIBILITY
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void
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sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t)
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{
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    using namespace chrono;
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    sleep_for(__t - steady_clock::now());
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}
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inline _LIBCPP_INLINE_VISIBILITY
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void yield() _NOEXCEPT {__libcpp_thread_yield();}
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}  // this_thread
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_LIBCPP_END_NAMESPACE_STD
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#endif // !_LIBCPP_HAS_NO_THREADS
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_LIBCPP_POP_MACROS
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#endif  // _LIBCPP_THREAD