1349cc55cSDimitry Andric //===----------------------------------------------------------------------===// 2349cc55cSDimitry Andric // 3349cc55cSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4349cc55cSDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 5349cc55cSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6349cc55cSDimitry Andric // 7349cc55cSDimitry Andric //===----------------------------------------------------------------------===// 8349cc55cSDimitry Andric 9349cc55cSDimitry Andric #ifndef _LIBCPP___COROUTINE_NOOP_COROUTINE_HANDLE_H 10349cc55cSDimitry Andric #define _LIBCPP___COROUTINE_NOOP_COROUTINE_HANDLE_H 11349cc55cSDimitry Andric 12349cc55cSDimitry Andric #include <__config> 13349cc55cSDimitry Andric #include <__coroutine/coroutine_handle.h> 14349cc55cSDimitry Andric 15349cc55cSDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 16349cc55cSDimitry Andric # pragma GCC system_header 17349cc55cSDimitry Andric #endif 18349cc55cSDimitry Andric 1906c3fb27SDimitry Andric #if _LIBCPP_STD_VER >= 20 20349cc55cSDimitry Andric 21349cc55cSDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 22349cc55cSDimitry Andric 2304eeddc0SDimitry Andric # if __has_builtin(__builtin_coro_noop) || defined(_LIBCPP_COMPILER_GCC) 2404eeddc0SDimitry Andric 25349cc55cSDimitry Andric // [coroutine.noop] 26349cc55cSDimitry Andric // [coroutine.promise.noop] 27349cc55cSDimitry Andric struct noop_coroutine_promise {}; 28349cc55cSDimitry Andric 29349cc55cSDimitry Andric // [coroutine.handle.noop] 30349cc55cSDimitry Andric template <> 31349cc55cSDimitry Andric struct _LIBCPP_TEMPLATE_VIS coroutine_handle<noop_coroutine_promise> { 32349cc55cSDimitry Andric public: 33349cc55cSDimitry Andric // [coroutine.handle.noop.conv], conversion 34*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr operator coroutine_handle<>() const noexcept { 35349cc55cSDimitry Andric return coroutine_handle<>::from_address(address()); 36349cc55cSDimitry Andric } 37349cc55cSDimitry Andric 38349cc55cSDimitry Andric // [coroutine.handle.noop.observers], observers 39*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return true; } 40*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr bool done() const noexcept { return false; } 41349cc55cSDimitry Andric 42349cc55cSDimitry Andric // [coroutine.handle.noop.resumption], resumption 43*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr void operator()() const noexcept {} 44*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr void resume() const noexcept {} 45*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr void destroy() const noexcept {} 46349cc55cSDimitry Andric 47349cc55cSDimitry Andric // [coroutine.handle.noop.promise], promise access 48*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI noop_coroutine_promise& promise() const noexcept { 49349cc55cSDimitry Andric return *static_cast<noop_coroutine_promise*>( 50349cc55cSDimitry Andric __builtin_coro_promise(this->__handle_, alignof(noop_coroutine_promise), false)); 51349cc55cSDimitry Andric } 52349cc55cSDimitry Andric 53349cc55cSDimitry Andric // [coroutine.handle.noop.address], address 54*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr void* address() const noexcept { return __handle_; } 55349cc55cSDimitry Andric 56349cc55cSDimitry Andric private: 57*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI friend coroutine_handle<noop_coroutine_promise> noop_coroutine() noexcept; 58349cc55cSDimitry Andric 5904eeddc0SDimitry Andric # if __has_builtin(__builtin_coro_noop) 60*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI coroutine_handle() noexcept { this->__handle_ = __builtin_coro_noop(); } 61349cc55cSDimitry Andric 62349cc55cSDimitry Andric void* __handle_ = nullptr; 6304eeddc0SDimitry Andric 6404eeddc0SDimitry Andric # elif defined(_LIBCPP_COMPILER_GCC) 6504eeddc0SDimitry Andric // GCC doesn't implement __builtin_coro_noop(). 6604eeddc0SDimitry Andric // Construct the coroutine frame manually instead. 6704eeddc0SDimitry Andric struct __noop_coroutine_frame_ty_ { 6804eeddc0SDimitry Andric static void __dummy_resume_destroy_func() {} 6904eeddc0SDimitry Andric 7004eeddc0SDimitry Andric void (*__resume_)() = __dummy_resume_destroy_func; 7104eeddc0SDimitry Andric void (*__destroy_)() = __dummy_resume_destroy_func; 7204eeddc0SDimitry Andric struct noop_coroutine_promise __promise_; 7304eeddc0SDimitry Andric }; 7404eeddc0SDimitry Andric 7504eeddc0SDimitry Andric static __noop_coroutine_frame_ty_ __noop_coroutine_frame_; 7604eeddc0SDimitry Andric 7704eeddc0SDimitry Andric void* __handle_ = &__noop_coroutine_frame_; 7804eeddc0SDimitry Andric 7904eeddc0SDimitry Andric _LIBCPP_HIDE_FROM_ABI coroutine_handle() noexcept = default; 8004eeddc0SDimitry Andric 8104eeddc0SDimitry Andric # endif // __has_builtin(__builtin_coro_noop) 82349cc55cSDimitry Andric }; 83349cc55cSDimitry Andric 84349cc55cSDimitry Andric using noop_coroutine_handle = coroutine_handle<noop_coroutine_promise>; 85349cc55cSDimitry Andric 8604eeddc0SDimitry Andric # if defined(_LIBCPP_COMPILER_GCC) 87*cb14a3feSDimitry Andric inline noop_coroutine_handle::__noop_coroutine_frame_ty_ noop_coroutine_handle::__noop_coroutine_frame_{}; 8804eeddc0SDimitry Andric # endif 8904eeddc0SDimitry Andric 90349cc55cSDimitry Andric // [coroutine.noop.coroutine] 91*cb14a3feSDimitry Andric inline _LIBCPP_HIDE_FROM_ABI noop_coroutine_handle noop_coroutine() noexcept { return noop_coroutine_handle(); } 92349cc55cSDimitry Andric 9304eeddc0SDimitry Andric # endif // __has_builtin(__builtin_coro_noop) || defined(_LIBCPP_COMPILER_GCC) 94349cc55cSDimitry Andric 95349cc55cSDimitry Andric _LIBCPP_END_NAMESPACE_STD 96349cc55cSDimitry Andric 9706c3fb27SDimitry Andric #endif // __LIBCPP_STD_VER >= 20 98349cc55cSDimitry Andric 99349cc55cSDimitry Andric #endif // _LIBCPP___COROUTINE_NOOP_COROUTINE_HANDLE_H 100