jdk

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/*
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 * Copyright (c) 2018, 2022, Oracle and/or its affiliates. All rights reserved.
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * This code is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 only, as
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 * published by the Free Software Foundation.
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 *
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * accompanied this code).
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 *
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 * You should have received a copy of the GNU General Public License version
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 *
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * or visit www.oracle.com if you need additional information or have any
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 * questions.
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 */
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#include "precompiled.hpp"
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#include "code/nmethod.hpp"
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#include "gc/x/xBarrierSetNMethod.hpp"
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#include "gc/x/xGlobals.hpp"
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#include "gc/x/xLock.inline.hpp"
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#include "gc/x/xNMethod.hpp"
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#include "gc/x/xThreadLocalData.hpp"
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#include "logging/log.hpp"
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#include "runtime/threadWXSetters.inline.hpp"
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bool XBarrierSetNMethod::nmethod_entry_barrier(nmethod* nm) {
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  if (!is_armed(nm)) {
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    // Some other thread got here first and healed the oops
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    // and disarmed the nmethod. No need to continue.
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    return true;
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  }
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  XLocker<XReentrantLock> locker(XNMethod::lock_for_nmethod(nm));
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  log_trace(nmethod, barrier)("Entered critical zone for %p", nm);
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  if (!is_armed(nm)) {
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    // Some other thread managed to complete while we were
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    // waiting for lock. No need to continue.
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    return true;
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  }
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  MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, Thread::current()));
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  if (nm->is_unloading()) {
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    // We don't need to take the lock when unlinking nmethods from
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    // the Method, because it is only concurrently unlinked by
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    // the entry barrier, which acquires the per nmethod lock.
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    nm->unlink_from_method();
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    // We can end up calling nmethods that are unloading
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    // since we clear compiled ICs lazily. Returning false
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    // will re-resovle the call and update the compiled IC.
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    return false;
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  }
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  // Heal oops
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  XNMethod::nmethod_oops_barrier(nm);
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  // CodeCache unloading support
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  nm->mark_as_maybe_on_stack();
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  // Disarm
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  disarm(nm);
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  return true;
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}
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int* XBarrierSetNMethod::disarmed_guard_value_address() const {
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  return (int*)XAddressBadMaskHighOrderBitsAddr;
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}
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ByteSize XBarrierSetNMethod::thread_disarmed_guard_value_offset() const {
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  return XThreadLocalData::nmethod_disarmed_offset();
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}
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