| /* |
| * 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 |