| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef _LIBCPP___COROUTINE_COROUTINE_HANDLE_H |
| #define _LIBCPP___COROUTINE_COROUTINE_HANDLE_H |
| |
| #include <__config> |
| #include <__debug> |
| #include <__functional/hash.h> |
| #include <__memory/addressof.h> |
| #include <compare> |
| #include <type_traits> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| #pragma GCC system_header |
| #endif |
| |
| #if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CXX20_COROUTINES) |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| // [coroutine.handle] |
| template <class _Promise = void> |
| struct _LIBCPP_TEMPLATE_VIS coroutine_handle; |
| |
| template <> |
| struct _LIBCPP_TEMPLATE_VIS coroutine_handle<void> { |
| public: |
| // [coroutine.handle.con], construct/reset |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr coroutine_handle() noexcept = default; |
| |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr coroutine_handle(nullptr_t) noexcept {} |
| |
| _LIBCPP_HIDE_FROM_ABI |
| coroutine_handle& operator=(nullptr_t) noexcept { |
| __handle_ = nullptr; |
| return *this; |
| } |
| |
| // [coroutine.handle.export.import], export/import |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr void* address() const noexcept { return __handle_; } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| static constexpr coroutine_handle from_address(void* __addr) noexcept { |
| coroutine_handle __tmp; |
| __tmp.__handle_ = __addr; |
| return __tmp; |
| } |
| |
| // [coroutine.handle.observers], observers |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr explicit operator bool() const noexcept { |
| return __handle_ != nullptr; |
| } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| bool done() const { |
| _LIBCPP_ASSERT(__is_suspended(), "done() can be called only on suspended coroutines"); |
| return __builtin_coro_done(__handle_); |
| } |
| |
| // [coroutine.handle.resumption], resumption |
| _LIBCPP_HIDE_FROM_ABI |
| void operator()() const { resume(); } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| void resume() const { |
| _LIBCPP_ASSERT(__is_suspended(), "resume() can be called only on suspended coroutines"); |
| _LIBCPP_ASSERT(!done(), "resume() has undefined behavior when the coroutine is done"); |
| __builtin_coro_resume(__handle_); |
| } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| void destroy() const { |
| _LIBCPP_ASSERT(__is_suspended(), "destroy() can be called only on suspended coroutines"); |
| __builtin_coro_destroy(__handle_); |
| } |
| |
| private: |
| bool __is_suspended() const { |
| // FIXME actually implement a check for if the coro is suspended. |
| return __handle_ != nullptr; |
| } |
| |
| void* __handle_ = nullptr; |
| }; |
| |
| // [coroutine.handle.compare] |
| inline _LIBCPP_HIDE_FROM_ABI |
| constexpr bool operator==(coroutine_handle<> __x, coroutine_handle<> __y) noexcept { |
| return __x.address() == __y.address(); |
| } |
| inline _LIBCPP_HIDE_FROM_ABI |
| constexpr strong_ordering operator<=>(coroutine_handle<> __x, coroutine_handle<> __y) noexcept { |
| return compare_three_way()(__x.address(), __y.address()); |
| } |
| |
| template <class _Promise> |
| struct _LIBCPP_TEMPLATE_VIS coroutine_handle { |
| public: |
| // [coroutine.handle.con], construct/reset |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr coroutine_handle() noexcept = default; |
| |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr coroutine_handle(nullptr_t) noexcept {} |
| |
| _LIBCPP_HIDE_FROM_ABI |
| static coroutine_handle from_promise(_Promise& __promise) { |
| using _RawPromise = typename remove_cv<_Promise>::type; |
| coroutine_handle __tmp; |
| __tmp.__handle_ = |
| __builtin_coro_promise(_VSTD::addressof(const_cast<_RawPromise&>(__promise)), alignof(_Promise), true); |
| return __tmp; |
| } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| coroutine_handle& operator=(nullptr_t) noexcept { |
| __handle_ = nullptr; |
| return *this; |
| } |
| |
| // [coroutine.handle.export.import], export/import |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr void* address() const noexcept { return __handle_; } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| static constexpr coroutine_handle from_address(void* __addr) noexcept { |
| coroutine_handle __tmp; |
| __tmp.__handle_ = __addr; |
| return __tmp; |
| } |
| |
| // [coroutine.handle.conv], conversion |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr operator coroutine_handle<>() const noexcept { |
| return coroutine_handle<>::from_address(address()); |
| } |
| |
| // [coroutine.handle.observers], observers |
| _LIBCPP_HIDE_FROM_ABI |
| constexpr explicit operator bool() const noexcept { |
| return __handle_ != nullptr; |
| } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| bool done() const { |
| _LIBCPP_ASSERT(__is_suspended(), "done() can be called only on suspended coroutines"); |
| return __builtin_coro_done(__handle_); |
| } |
| |
| // [coroutine.handle.resumption], resumption |
| _LIBCPP_HIDE_FROM_ABI |
| void operator()() const { resume(); } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| void resume() const { |
| _LIBCPP_ASSERT(__is_suspended(), "resume() can be called only on suspended coroutines"); |
| _LIBCPP_ASSERT(!done(), "resume() has undefined behavior when the coroutine is done"); |
| __builtin_coro_resume(__handle_); |
| } |
| |
| _LIBCPP_HIDE_FROM_ABI |
| void destroy() const { |
| _LIBCPP_ASSERT(__is_suspended(), "destroy() can be called only on suspended coroutines"); |
| __builtin_coro_destroy(__handle_); |
| } |
| |
| // [coroutine.handle.promise], promise access |
| _LIBCPP_HIDE_FROM_ABI |
| _Promise& promise() const { |
| return *static_cast<_Promise*>(__builtin_coro_promise(this->__handle_, alignof(_Promise), false)); |
| } |
| |
| private: |
| bool __is_suspended() const { |
| // FIXME actually implement a check for if the coro is suspended. |
| return __handle_ != nullptr; |
| } |
| void* __handle_ = nullptr; |
| }; |
| |
| // [coroutine.handle.hash] |
| template <class _Tp> |
| struct hash<coroutine_handle<_Tp>> { |
| _LIBCPP_HIDE_FROM_ABI |
| size_t operator()(const coroutine_handle<_Tp>& __v) const noexcept { return hash<void*>()(__v.address()); } |
| }; |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // __LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CXX20_COROUTINES) |
| |
| #endif // _LIBCPP___COROUTINE_COROUTINE_HANDLE_H |