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@@ -1,503 +0,0 @@
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-// -*- C++ -*-
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-//===------------------------------- task ---------------------------------===//
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-//
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-// The LLVM Compiler Infrastructure
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-//
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-// This file is distributed under the University of Illinois Open Source
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-// License. See LICENSE.TXT for details.
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-//
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-//===----------------------------------------------------------------------===//
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-
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-#ifndef _LIBCPP_EXPERIMENTAL_TASK
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-#define _LIBCPP_EXPERIMENTAL_TASK
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-
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-#include <experimental/__config>
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-#include <experimental/__memory>
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-#include <experimental/coroutine>
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-
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-#include <exception>
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-#include <type_traits>
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-#include <utility>
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-
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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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-
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-#ifdef _LIBCPP_HAS_NO_COROUTINES
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-#if defined(_LIBCPP_WARNING)
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-_LIBCPP_WARNING("<experimental/task> cannot be used with this compiler")
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-#else
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-#warning <experimental/task> cannot be used with this compiler
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-#endif
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-#endif
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-
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-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_COROUTINES
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-
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-////// task<T>
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-
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-template <typename _Tp = void>
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-class task;
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-
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-struct __task_promise_final_awaitable {
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- _LIBCPP_INLINE_VISIBILITY
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- _LIBCPP_CONSTEXPR bool await_ready() const _NOEXCEPT { return false; }
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-
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- template <typename _TaskPromise>
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- _LIBCPP_INLINE_VISIBILITY coroutine_handle<>
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- await_suspend(coroutine_handle<_TaskPromise> __coro) const _NOEXCEPT {
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- _LIBCPP_ASSERT(
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- __coro.promise().__continuation_,
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- "Coroutine completed without a valid continuation attached.");
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- return __coro.promise().__continuation_;
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- }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- void await_resume() const _NOEXCEPT {}
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-};
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-
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-class _LIBCPP_TYPE_VIS __task_promise_base {
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- using _DeallocFunc = void(void* __ptr, size_t __size) _NOEXCEPT;
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-
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- template <typename _Alloc>
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- static constexpr bool __allocator_needs_to_be_stored =
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- !allocator_traits<_Alloc>::is_always_equal::value ||
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- !is_default_constructible_v<_Alloc>;
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-
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- static _LIBCPP_CONSTEXPR size_t
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- __get_dealloc_func_offset(size_t __frameSize) _NOEXCEPT {
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- return _VSTD_LFTS::__aligned_allocation_size(__frameSize,
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- alignof(_DeallocFunc*));
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- }
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-
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- static _LIBCPP_CONSTEXPR size_t
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- __get_padded_frame_size(size_t __frameSize) _NOEXCEPT {
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- return __get_dealloc_func_offset(__frameSize) + sizeof(_DeallocFunc*);
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- }
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-
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- template <typename _Alloc>
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- static _LIBCPP_CONSTEXPR size_t
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- __get_allocator_offset(size_t __frameSize) _NOEXCEPT {
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- return _VSTD_LFTS::__aligned_allocation_size(
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- __get_padded_frame_size(__frameSize), alignof(_Alloc));
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- }
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-
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- template <typename _Alloc>
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- static _LIBCPP_CONSTEXPR size_t
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- __get_padded_frame_size_with_allocator(size_t __frameSize) _NOEXCEPT {
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- if constexpr (__allocator_needs_to_be_stored<_Alloc>) {
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- return __get_allocator_offset<_Alloc>(__frameSize) + sizeof(_Alloc);
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- } else {
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- return __get_padded_frame_size(__frameSize);
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- }
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- }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- static _DeallocFunc*& __get_dealloc_func(void* __frameStart,
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- size_t __frameSize) _NOEXCEPT {
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- return *reinterpret_cast<_DeallocFunc**>(
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- static_cast<char*>(__frameStart) +
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- __get_dealloc_func_offset(__frameSize));
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- }
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-
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- template <typename _Alloc>
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- _LIBCPP_INLINE_VISIBILITY static _Alloc&
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- __get_allocator(void* __frameStart, size_t __frameSize) _NOEXCEPT {
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- return *reinterpret_cast<_Alloc*>(
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- static_cast<char*>(__frameStart) +
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- __get_allocator_offset<_Alloc>(__frameSize));
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- }
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-
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-public:
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- __task_promise_base() _NOEXCEPT = default;
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-
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- // Explicitly disable special member functions.
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- __task_promise_base(const __task_promise_base&) = delete;
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- __task_promise_base(__task_promise_base&&) = delete;
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- __task_promise_base& operator=(const __task_promise_base&) = delete;
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- __task_promise_base& operator=(__task_promise_base&&) = delete;
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-
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- static void* operator new(size_t __size) {
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- // Allocate space for an extra pointer immediately after __size that holds
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- // the type-erased deallocation function.
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- void* __pointer = ::operator new(__get_padded_frame_size(__size));
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-
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- _DeallocFunc*& __deallocFunc = __get_dealloc_func(__pointer, __size);
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- __deallocFunc = [](void* __pointer, size_t __size) _NOEXCEPT {
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- ::operator delete(__pointer, __get_padded_frame_size(__size));
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- };
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-
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- return __pointer;
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- }
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-
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- template <typename _Alloc, typename... _Args>
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- static void* operator new(size_t __size, allocator_arg_t, _Alloc& __alloc,
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- _Args&...) {
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- using _CharAlloc =
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- typename allocator_traits<_Alloc>::template rebind_alloc<char>;
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-
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- _CharAlloc __charAllocator{__alloc};
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-
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- void* __pointer = __charAllocator.allocate(
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- __get_padded_frame_size_with_allocator<_CharAlloc>(__size));
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-
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- _DeallocFunc*& __deallocFunc = __get_dealloc_func(__pointer, __size);
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- __deallocFunc = [](void* __pointer, size_t __size) _NOEXCEPT {
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- // Allocators are required to not throw from their move constructors
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- // however they aren't required to be declared noexcept so we can't
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- // actually check this with a static_assert.
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- //
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- // static_assert(is_nothrow_move_constructible<_Alloc>::value,
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- // "task<T> coroutine custom allocator requires a noexcept "
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- // "move constructor");
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-
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- size_t __paddedSize =
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- __get_padded_frame_size_with_allocator<_CharAlloc>(__size);
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-
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- if constexpr (__allocator_needs_to_be_stored<_CharAlloc>) {
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- _CharAlloc& __allocatorInFrame =
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- __get_allocator<_CharAlloc>(__pointer, __size);
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- _CharAlloc __allocatorOnStack = _VSTD::move(__allocatorInFrame);
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- __allocatorInFrame.~_CharAlloc();
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- // Allocator requirements state that deallocate() must not throw.
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- // See [allocator.requirements] from C++ standard.
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- // We are relying on that here.
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- __allocatorOnStack.deallocate(static_cast<char*>(__pointer),
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- __paddedSize);
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- } else {
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- _CharAlloc __alloc;
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- __alloc.deallocate(static_cast<char*>(__pointer), __paddedSize);
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- }
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- };
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-
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- // Copy the allocator into the heap frame (if required)
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- if constexpr (__allocator_needs_to_be_stored<_CharAlloc>) {
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- // task<T> coroutine custom allocation requires the copy constructor to
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- // not throw but we can't rely on it being declared noexcept.
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- // If it did throw we'd leak the allocation here.
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- ::new (static_cast<void*>(
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- _VSTD::addressof(__get_allocator<_CharAlloc>(__pointer, __size))))
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- _CharAlloc(_VSTD::move(__charAllocator));
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- }
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-
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- return __pointer;
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- }
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-
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- template <typename _This, typename _Alloc, typename... _Args>
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- static void* operator new(size_t __size, _This&, allocator_arg_t __allocArg, _Alloc& __alloc,
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- _Args&...) {
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- return __task_promise_base::operator new(__size, __allocArg, __alloc);
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- }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- static void operator delete(void* __pointer, size_t __size)_NOEXCEPT {
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- __get_dealloc_func(__pointer, __size)(__pointer, __size);
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- }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- suspend_always initial_suspend() const _NOEXCEPT { return {}; }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- __task_promise_final_awaitable final_suspend() _NOEXCEPT { return {}; }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- void __set_continuation(coroutine_handle<> __continuation) {
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- _LIBCPP_ASSERT(!__continuation_, "task already has a continuation");
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- __continuation_ = __continuation;
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- }
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-
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-private:
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- friend struct __task_promise_final_awaitable;
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-
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- coroutine_handle<> __continuation_;
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-};
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-
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-template <typename _Tp>
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-class _LIBCPP_TEMPLATE_VIS __task_promise final : public __task_promise_base {
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- using _Handle = coroutine_handle<__task_promise>;
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-
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-public:
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- __task_promise() _NOEXCEPT : __state_(_State::__no_value) {}
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-
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- ~__task_promise() {
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- switch (__state_) {
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- case _State::__value:
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- __value_.~_Tp();
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- break;
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-#ifndef _LIBCPP_NO_EXCEPTIONS
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- case _State::__exception:
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- __exception_.~exception_ptr();
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- break;
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-#endif
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- case _State::__no_value:
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- break;
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- };
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- }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- task<_Tp> get_return_object() _NOEXCEPT;
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-
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- void unhandled_exception() _NOEXCEPT {
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-#ifndef _LIBCPP_NO_EXCEPTIONS
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- ::new (static_cast<void*>(&__exception_))
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- exception_ptr(current_exception());
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- __state_ = _State::__exception;
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-#else
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- _LIBCPP_ASSERT(
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- false, "task<T> coroutine unexpectedly called unhandled_exception()");
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-#endif
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- }
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-
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- // Only enable return_value() overload if _Tp is implicitly constructible from
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- // _Value
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- template <typename _Value,
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- enable_if_t<is_convertible<_Value, _Tp>::value, int> = 0>
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- void return_value(_Value&& __value)
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- _NOEXCEPT_((is_nothrow_constructible_v<_Tp, _Value>)) {
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- __construct_value(static_cast<_Value&&>(__value));
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- }
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-
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- template <typename _Value>
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- auto return_value(std::initializer_list<_Value> __initializer) _NOEXCEPT_(
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- (is_nothrow_constructible_v<_Tp, std::initializer_list<_Value>>))
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- -> std::enable_if_t<
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- std::is_constructible_v<_Tp, std::initializer_list<_Value>>> {
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- __construct_value(_VSTD::move(__initializer));
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- }
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-
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- auto return_value(_Tp&& __value)
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- _NOEXCEPT_((is_nothrow_move_constructible_v<_Tp>))
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- -> std::enable_if_t<std::is_move_constructible_v<_Tp>> {
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- __construct_value(static_cast<_Tp&&>(__value));
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- }
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-
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- _Tp& __lvalue_result() {
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- __throw_if_exception();
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- return __value_;
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- }
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-
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- _Tp __rvalue_result() {
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- __throw_if_exception();
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- return static_cast<_Tp&&>(__value_);
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- }
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-
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-private:
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- template <typename... _Args>
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- void __construct_value(_Args&&... __args) {
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- ::new (static_cast<void*>(_VSTD::addressof(__value_)))
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- _Tp(static_cast<_Args&&>(__args)...);
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-
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- // Only set __state_ after successfully constructing the value.
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- // If constructor throws then state will be updated by
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- // unhandled_exception().
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- __state_ = _State::__value;
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- }
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-
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- void __throw_if_exception() {
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-#ifndef _LIBCPP_NO_EXCEPTIONS
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- if (__state_ == _State::__exception) {
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- rethrow_exception(__exception_);
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- }
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-#endif
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- }
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-
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- enum class _State { __no_value, __value, __exception };
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-
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- _State __state_ = _State::__no_value;
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- union {
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- char __empty_;
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- _Tp __value_;
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- exception_ptr __exception_;
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- };
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-};
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-
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-template <typename _Tp>
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-class __task_promise<_Tp&> final : public __task_promise_base {
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- using _Ptr = _Tp*;
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- using _Handle = coroutine_handle<__task_promise>;
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-
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-public:
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- __task_promise() _NOEXCEPT = default;
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-
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- ~__task_promise() {
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-#ifndef _LIBCPP_NO_EXCEPTIONS
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- if (__has_exception_) {
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- __exception_.~exception_ptr();
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- }
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-#endif
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- }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- task<_Tp&> get_return_object() _NOEXCEPT;
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-
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- void unhandled_exception() _NOEXCEPT {
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-#ifndef _LIBCPP_NO_EXCEPTIONS
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- ::new (static_cast<void*>(&__exception_))
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- exception_ptr(current_exception());
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- __has_exception_ = true;
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-#else
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- _LIBCPP_ASSERT(
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- false, "task<T> coroutine unexpectedly called unhandled_exception()");
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-#endif
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- }
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-
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- void return_value(_Tp& __value) _NOEXCEPT {
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- ::new (static_cast<void*>(&__pointer_)) _Ptr(_VSTD::addressof(__value));
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- }
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-
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- _Tp& __lvalue_result() {
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- __throw_if_exception();
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- return *__pointer_;
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- }
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-
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- _Tp& __rvalue_result() { return __lvalue_result(); }
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-
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-private:
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- void __throw_if_exception() {
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-#ifndef _LIBCPP_NO_EXCEPTIONS
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- if (__has_exception_) {
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- rethrow_exception(__exception_);
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- }
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-#endif
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- }
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-
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- union {
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- char __empty_;
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- _Ptr __pointer_;
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- exception_ptr __exception_;
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- };
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- bool __has_exception_ = false;
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-};
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-
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-template <>
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-class __task_promise<void> final : public __task_promise_base {
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- using _Handle = coroutine_handle<__task_promise>;
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-
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-public:
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- task<void> get_return_object() _NOEXCEPT;
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-
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- void return_void() _NOEXCEPT {}
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-
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- void unhandled_exception() _NOEXCEPT {
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-#ifndef _LIBCPP_NO_EXCEPTIONS
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- __exception_ = current_exception();
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-#endif
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- }
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-
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- void __lvalue_result() { __throw_if_exception(); }
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-
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- void __rvalue_result() { __throw_if_exception(); }
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-
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-private:
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- void __throw_if_exception() {
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-#ifndef _LIBCPP_NO_EXCEPTIONS
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- if (__exception_) {
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- rethrow_exception(__exception_);
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- }
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-#endif
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- }
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-
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- exception_ptr __exception_;
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-};
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-
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-template <typename _Tp>
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-class _LIBCPP_TEMPLATE_VIS _LIBCPP_NODISCARD_AFTER_CXX17 task {
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-public:
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- using promise_type = __task_promise<_Tp>;
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-
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-private:
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- using _Handle = coroutine_handle<__task_promise<_Tp>>;
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-
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- class _AwaiterBase {
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- public:
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- _AwaiterBase(_Handle __coro) _NOEXCEPT : __coro_(__coro) {}
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-
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- _LIBCPP_INLINE_VISIBILITY
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- bool await_ready() const { return __coro_.done(); }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- _Handle await_suspend(coroutine_handle<> __continuation) const {
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- __coro_.promise().__set_continuation(__continuation);
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- return __coro_;
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- }
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-
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- protected:
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- _Handle __coro_;
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- };
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-
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-public:
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- _LIBCPP_INLINE_VISIBILITY
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- task(task&& __other) _NOEXCEPT
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- : __coro_(_VSTD::exchange(__other.__coro_, {})) {}
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-
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- task(const task&) = delete;
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- task& operator=(const task&) = delete;
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-
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- _LIBCPP_INLINE_VISIBILITY
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- ~task() {
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- if (__coro_)
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- __coro_.destroy();
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- }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- void swap(task& __other) _NOEXCEPT { _VSTD::swap(__coro_, __other.__coro_); }
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-
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- _LIBCPP_INLINE_VISIBILITY
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- auto operator co_await() & {
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- class _Awaiter : public _AwaiterBase {
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- public:
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- using _AwaiterBase::_AwaiterBase;
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-
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- _LIBCPP_INLINE_VISIBILITY
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- decltype(auto) await_resume() {
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- return this->__coro_.promise().__lvalue_result();
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- }
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- };
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-
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- _LIBCPP_ASSERT(__coro_,
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- "Undefined behaviour to co_await an invalid task<T>");
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- return _Awaiter{__coro_};
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- }
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-
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- _LIBCPP_INLINE_VISIBILITY
|
|
|
- auto operator co_await() && {
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|
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- class _Awaiter : public _AwaiterBase {
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- public:
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- using _AwaiterBase::_AwaiterBase;
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-
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- _LIBCPP_INLINE_VISIBILITY
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- decltype(auto) await_resume() {
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- return this->__coro_.promise().__rvalue_result();
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- }
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- };
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-
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- _LIBCPP_ASSERT(__coro_,
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|
- "Undefined behaviour to co_await an invalid task<T>");
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- return _Awaiter{__coro_};
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- }
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-
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-private:
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- friend class __task_promise<_Tp>;
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-
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- _LIBCPP_INLINE_VISIBILITY
|
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- task(_Handle __coro) _NOEXCEPT : __coro_(__coro) {}
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-
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- _Handle __coro_;
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-};
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-
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-template <typename _Tp>
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-task<_Tp> __task_promise<_Tp>::get_return_object() _NOEXCEPT {
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- return task<_Tp>{_Handle::from_promise(*this)};
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-}
|
|
|
-
|
|
|
-template <typename _Tp>
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|
|
-task<_Tp&> __task_promise<_Tp&>::get_return_object() _NOEXCEPT {
|
|
|
- return task<_Tp&>{_Handle::from_promise(*this)};
|
|
|
-}
|
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-
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|
|
-task<void> __task_promise<void>::get_return_object() _NOEXCEPT {
|
|
|
- return task<void>{_Handle::from_promise(*this)};
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|
|
-}
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-
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-_LIBCPP_END_NAMESPACE_EXPERIMENTAL_COROUTINES
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-
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-#endif
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