/*
* Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#ifndef SHARE_VM_RUNTIME_PREFETCH_HPP
#define SHARE_VM_RUNTIME_PREFETCH_HPP
#include "memory/allocation.hpp"
// If calls to prefetch methods are in a loop, the loop should be cloned
// such that if Prefetch{Scan,Copy}Interval and/or PrefetchFieldInterval
// say not to do prefetching, these methods aren't called. At the very
// least, they take up a memory issue slot. They should be implemented
// as inline assembly code: doing an actual call isn't worth the cost.
class Prefetch : AllStatic {
public:
enum style {
do_none, // Do no prefetching
do_read, // Do read prefetching
do_write // Do write prefetching
};
// Prefetch anticipating read; must not fault, semantically a no-op
static void read(void* loc, intx interval);
// Prefetch anticipating write; must not fault, semantically a no-op
static void write(void* loc, intx interval);
};
#endif // SHARE_VM_RUNTIME_PREFETCH_HPP