Thu, 15 Apr 2010 02:40:12 -0700
6941224: Improved stack overflow handling for Zero
Summary: Adding stack overflow checking to Shark brought to light a bunch of deficiencies in Zero's stack overflow code.
Reviewed-by: twisti
Contributed-by: Gary Benson <gbenson@redhat.com>
never@1445 | 1 | /* |
never@1445 | 2 | * Copyright 2003-2005 Sun Microsystems, Inc. All Rights Reserved. |
never@1445 | 3 | * Copyright 2007, 2008 Red Hat, Inc. |
never@1445 | 4 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
never@1445 | 5 | * |
never@1445 | 6 | * This code is free software; you can redistribute it and/or modify it |
never@1445 | 7 | * under the terms of the GNU General Public License version 2 only, as |
never@1445 | 8 | * published by the Free Software Foundation. |
never@1445 | 9 | * |
never@1445 | 10 | * This code is distributed in the hope that it will be useful, but WITHOUT |
never@1445 | 11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
never@1445 | 12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
never@1445 | 13 | * version 2 for more details (a copy is included in the LICENSE file that |
never@1445 | 14 | * accompanied this code). |
never@1445 | 15 | * |
never@1445 | 16 | * You should have received a copy of the GNU General Public License version |
never@1445 | 17 | * 2 along with this work; if not, write to the Free Software Foundation, |
never@1445 | 18 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
never@1445 | 19 | * |
never@1445 | 20 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
never@1445 | 21 | * CA 95054 USA or visit www.sun.com if you need additional information or |
never@1445 | 22 | * have any questions. |
never@1445 | 23 | * |
never@1445 | 24 | */ |
never@1445 | 25 | |
never@1445 | 26 | public: |
never@1445 | 27 | // Each arch must define reset, save, restore |
never@1445 | 28 | // These are used by objects that only care about: |
never@1445 | 29 | // 1 - initializing a new state (thread creation, javaCalls) |
never@1445 | 30 | // 2 - saving a current state (javaCalls) |
never@1445 | 31 | // 3 - restoring an old state (javaCalls) |
never@1445 | 32 | |
never@1445 | 33 | void clear() { |
never@1445 | 34 | // clearing _last_Java_sp must be first |
never@1445 | 35 | _last_Java_sp = NULL; |
never@1445 | 36 | // fence? |
never@1445 | 37 | _last_Java_pc = NULL; |
never@1445 | 38 | } |
never@1445 | 39 | |
never@1445 | 40 | void copy(JavaFrameAnchor* src) { |
never@1445 | 41 | // In order to make sure the transition state is valid for "this" |
never@1445 | 42 | // We must clear _last_Java_sp before copying the rest of the new |
never@1445 | 43 | // data |
never@1445 | 44 | // |
never@1445 | 45 | // Hack Alert: Temporary bugfix for 4717480/4721647 To act like |
never@1445 | 46 | // previous version (pd_cache_state) don't NULL _last_Java_sp |
never@1445 | 47 | // unless the value is changing |
never@1445 | 48 | // |
never@1445 | 49 | if (_last_Java_sp != src->_last_Java_sp) |
never@1445 | 50 | _last_Java_sp = NULL; |
never@1445 | 51 | |
never@1445 | 52 | _last_Java_pc = src->_last_Java_pc; |
never@1445 | 53 | // Must be last so profiler will always see valid frame if |
never@1445 | 54 | // has_last_frame() is true |
never@1445 | 55 | _last_Java_sp = src->_last_Java_sp; |
never@1445 | 56 | } |
never@1445 | 57 | |
never@1445 | 58 | bool walkable() { |
never@1445 | 59 | return true; |
never@1445 | 60 | } |
never@1445 | 61 | |
never@1445 | 62 | void make_walkable(JavaThread* thread) { |
never@1445 | 63 | // nothing to do |
never@1445 | 64 | } |
never@1445 | 65 | |
never@1445 | 66 | intptr_t* last_Java_sp() const { |
never@1445 | 67 | return _last_Java_sp; |
never@1445 | 68 | } |
never@1445 | 69 | |
never@1445 | 70 | void set_last_Java_sp(intptr_t* sp) { |
never@1445 | 71 | _last_Java_sp = sp; |
never@1445 | 72 | } |