blob: da13d579604b55ca33d040617adfb09cab863681 [file] [log] [blame]
//===----------------------------------------------------------------------===//
//
// 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_NOOP_COROUTINE_HANDLE_H
#define _LIBCPP___COROUTINE_NOOP_COROUTINE_HANDLE_H
#include <__config>
#include <__coroutine/coroutine_handle.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
#if _LIBCPP_STD_VER >= 20
_LIBCPP_BEGIN_NAMESPACE_STD
# if __has_builtin(__builtin_coro_noop) || defined(_LIBCPP_COMPILER_GCC)
// [coroutine.noop]
// [coroutine.promise.noop]
struct noop_coroutine_promise {};
// [coroutine.handle.noop]
template <>
struct _LIBCPP_TEMPLATE_VIS coroutine_handle<noop_coroutine_promise> {
public:
// [coroutine.handle.noop.conv], conversion
_LIBCPP_HIDE_FROM_ABI constexpr operator coroutine_handle<>() const noexcept {
return coroutine_handle<>::from_address(address());
}
// [coroutine.handle.noop.observers], observers
_LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return true; }
_LIBCPP_HIDE_FROM_ABI constexpr bool done() const noexcept { return false; }
// [coroutine.handle.noop.resumption], resumption
_LIBCPP_HIDE_FROM_ABI constexpr void operator()() const noexcept {}
_LIBCPP_HIDE_FROM_ABI constexpr void resume() const noexcept {}
_LIBCPP_HIDE_FROM_ABI constexpr void destroy() const noexcept {}
// [coroutine.handle.noop.promise], promise access
_LIBCPP_HIDE_FROM_ABI noop_coroutine_promise& promise() const noexcept {
return *static_cast<noop_coroutine_promise*>(
__builtin_coro_promise(this->__handle_, alignof(noop_coroutine_promise), false));
}
// [coroutine.handle.noop.address], address
_LIBCPP_HIDE_FROM_ABI constexpr void* address() const noexcept { return __handle_; }
private:
_LIBCPP_HIDE_FROM_ABI friend coroutine_handle<noop_coroutine_promise> noop_coroutine() noexcept;
# if __has_builtin(__builtin_coro_noop)
_LIBCPP_HIDE_FROM_ABI coroutine_handle() noexcept { this->__handle_ = __builtin_coro_noop(); }
void* __handle_ = nullptr;
# elif defined(_LIBCPP_COMPILER_GCC)
// GCC doesn't implement __builtin_coro_noop().
// Construct the coroutine frame manually instead.
struct __noop_coroutine_frame_ty_ {
static void __dummy_resume_destroy_func() {}
void (*__resume_)() = __dummy_resume_destroy_func;
void (*__destroy_)() = __dummy_resume_destroy_func;
struct noop_coroutine_promise __promise_;
};
static __noop_coroutine_frame_ty_ __noop_coroutine_frame_;
void* __handle_ = &__noop_coroutine_frame_;
_LIBCPP_HIDE_FROM_ABI coroutine_handle() noexcept = default;
# endif // __has_builtin(__builtin_coro_noop)
};
using noop_coroutine_handle = coroutine_handle<noop_coroutine_promise>;
# if defined(_LIBCPP_COMPILER_GCC)
inline noop_coroutine_handle::__noop_coroutine_frame_ty_ noop_coroutine_handle::__noop_coroutine_frame_{};
# endif
// [coroutine.noop.coroutine]
inline _LIBCPP_HIDE_FROM_ABI noop_coroutine_handle noop_coroutine() noexcept { return noop_coroutine_handle(); }
# endif // __has_builtin(__builtin_coro_noop) || defined(_LIBCPP_COMPILER_GCC)
_LIBCPP_END_NAMESPACE_STD
#endif // __LIBCPP_STD_VER >= 20
#endif // _LIBCPP___COROUTINE_NOOP_COROUTINE_HANDLE_H