src/share/vm/utilities/preserveException.hpp

Thu, 20 Nov 2008 16:56:09 -0800

author
ysr
date
Thu, 20 Nov 2008 16:56:09 -0800
changeset 888
c96030fff130
parent 435
a61af66fc99e
child 1907
c18cbe5936b8
permissions
-rw-r--r--

6684579: SoftReference processing can be made more efficient
Summary: For current soft-ref clearing policies, we can decide at marking time if a soft-reference will definitely not be cleared, postponing the decision of whether it will definitely be cleared to the final reference processing phase. This can be especially beneficial in the case of concurrent collectors where the marking is usually concurrent but reference processing is usually not.
Reviewed-by: jmasa

duke@435 1 /*
duke@435 2 * Copyright 1998-2006 Sun Microsystems, Inc. All Rights Reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
duke@435 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435 20 * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435 21 * have any questions.
duke@435 22 *
duke@435 23 */
duke@435 24
duke@435 25 // This file provides more support for exception handling; see also exceptions.hpp
duke@435 26 class PreserveExceptionMark {
duke@435 27 private:
duke@435 28 Thread* _thread;
duke@435 29 Handle _preserved_exception_oop;
duke@435 30 int _preserved_exception_line;
duke@435 31 const char* _preserved_exception_file;
duke@435 32
duke@435 33 public:
duke@435 34 PreserveExceptionMark(Thread*& thread);
duke@435 35 ~PreserveExceptionMark();
duke@435 36 };
duke@435 37
duke@435 38
duke@435 39 // This is a clone of PreserveExceptionMark which asserts instead
duke@435 40 // of failing when what it wraps generates a pending exception.
duke@435 41 // It also addresses bug 6431341.
duke@435 42 class CautiouslyPreserveExceptionMark {
duke@435 43 private:
duke@435 44 Thread* _thread;
duke@435 45 Handle _preserved_exception_oop;
duke@435 46 int _preserved_exception_line;
duke@435 47 const char* _preserved_exception_file;
duke@435 48
duke@435 49 public:
duke@435 50 CautiouslyPreserveExceptionMark(Thread* thread);
duke@435 51 ~CautiouslyPreserveExceptionMark();
duke@435 52 };
duke@435 53
duke@435 54
duke@435 55 // Like PreserveExceptionMark but allows new exceptions to be generated in
duke@435 56 // the body of the mark. If a new exception is generated then the original one
duke@435 57 // is discarded.
duke@435 58 class WeakPreserveExceptionMark {
duke@435 59 private:
duke@435 60 Thread* _thread;
duke@435 61 Handle _preserved_exception_oop;
duke@435 62 int _preserved_exception_line;
duke@435 63 const char* _preserved_exception_file;
duke@435 64
duke@435 65 void preserve();
duke@435 66 void restore();
duke@435 67
duke@435 68 public:
duke@435 69 WeakPreserveExceptionMark(Thread* pThread) : _thread(pThread), _preserved_exception_oop() {
duke@435 70 if (pThread->has_pending_exception()) {
duke@435 71 preserve();
duke@435 72 }
duke@435 73 }
duke@435 74 ~WeakPreserveExceptionMark() {
duke@435 75 if (_preserved_exception_oop.not_null()) {
duke@435 76 restore();
duke@435 77 }
duke@435 78 }
duke@435 79 };
duke@435 80
duke@435 81
duke@435 82
duke@435 83 // use global exception mark when allowing pending exception to be set and
duke@435 84 // saving and restoring them
duke@435 85 #define PRESERVE_EXCEPTION_MARK Thread* THREAD; PreserveExceptionMark __em(THREAD);

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