Thu, 07 Apr 2011 09:53:20 -0700
7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error
Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.
Reviewed-by: kvn, iveresov, never, tonyp, dholmes
1 /*
2 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #ifndef CPU_SPARC_VM_CPPINTERPRETER_SPARC_HPP
26 #define CPU_SPARC_VM_CPPINTERPRETER_SPARC_HPP
28 // Size of interpreter code. Increase if too small. Interpreter will
29 // fail with a guarantee ("not enough space for interpreter generation");
30 // if too small.
31 // Run with +PrintInterpreter to get the VM to print out the size.
32 // Max size with JVMTI
34 // QQQ this is proably way too large for c++ interpreter
36 #ifdef _LP64
37 // The sethi() instruction generates lots more instructions when shell
38 // stack limit is unlimited, so that's why this is much bigger.
39 const static int InterpreterCodeSize = 210 * K;
40 #else
41 const static int InterpreterCodeSize = 180 * K;
42 #endif
44 #endif // CPU_SPARC_VM_CPPINTERPRETER_SPARC_HPP