zig/lib/libcxx/include/__thread/timed_backoff_policy.h
Andrew Kelley 06ee65af9e libcxx: update to LLVM 18
release/18.x branch, commit 78b99c73ee4b96fe9ce0e294d4632326afb2db42

This adds the flag `-D_LIBCPP_HARDENING_MODE` which is determined based
on the Zig optimization mode.

This commit also fixes libunwind, libcxx, and libcxxabi to properly
report sub compilation errors.
2024-05-08 19:37:29 -07:00

44 lines
1.3 KiB
C++
Vendored

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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___THREAD_TIMED_BACKOFF_POLICY_H
#define _LIBCPP___THREAD_TIMED_BACKOFF_POLICY_H
#include <__config>
#ifndef _LIBCPP_HAS_NO_THREADS
# include <__chrono/duration.h>
# include <__threading_support>
# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
# endif
_LIBCPP_BEGIN_NAMESPACE_STD
struct __libcpp_timed_backoff_policy {
_LIBCPP_HIDE_FROM_ABI bool operator()(chrono::nanoseconds __elapsed) const {
if (__elapsed > chrono::milliseconds(128))
__libcpp_thread_sleep_for(chrono::milliseconds(8));
else if (__elapsed > chrono::microseconds(64))
__libcpp_thread_sleep_for(__elapsed / 2);
else if (__elapsed > chrono::microseconds(4))
__libcpp_thread_yield();
else {
} // poll
return false;
}
};
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP_HAS_NO_THREADS
#endif // _LIBCPP___THREAD_TIMED_BACKOFF_POLICY_H