locknode.cpp revision 1879:f95d63e2154a 
1/*
2 * Copyright (c) 1999, 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 */
24
25#include "precompiled.hpp"
26#include "opto/locknode.hpp"
27#include "opto/parse.hpp"
28#include "opto/rootnode.hpp"
29#include "opto/runtime.hpp"
30
31//=============================================================================
32const RegMask &BoxLockNode::in_RegMask(uint i) const {
33  return _inmask;
34}
35
36const RegMask &BoxLockNode::out_RegMask() const {
37  return *Matcher::idealreg2regmask[Op_RegP];
38}
39
40uint BoxLockNode::size_of() const { return sizeof(*this); }
41
42BoxLockNode::BoxLockNode( int slot ) : Node( Compile::current()->root() ),
43                                       _slot(slot), _is_eliminated(false) {
44  init_class_id(Class_BoxLock);
45  init_flags(Flag_rematerialize);
46  OptoReg::Name reg = OptoReg::stack2reg(_slot);
47  _inmask.Insert(reg);
48}
49
50//-----------------------------hash--------------------------------------------
51uint BoxLockNode::hash() const {
52  return Node::hash() + _slot + (_is_eliminated ? Compile::current()->fixed_slots() : 0);
53}
54
55//------------------------------cmp--------------------------------------------
56uint BoxLockNode::cmp( const Node &n ) const {
57  const BoxLockNode &bn = (const BoxLockNode &)n;
58  return bn._slot == _slot && bn._is_eliminated == _is_eliminated;
59}
60
61OptoReg::Name BoxLockNode::stack_slot(Node* box_node) {
62  // Chase down the BoxNode
63  while (!box_node->is_BoxLock()) {
64    //    if (box_node->is_SpillCopy()) {
65    //      Node *m = box_node->in(1);
66    //      if (m->is_Mach() && m->as_Mach()->ideal_Opcode() == Op_StoreP) {
67    //        box_node = m->in(m->as_Mach()->operand_index(2));
68    //        continue;
69    //      }
70    //    }
71    assert(box_node->is_SpillCopy() || box_node->is_Phi(), "Bad spill of Lock.");
72    box_node = box_node->in(1);
73  }
74  return box_node->in_RegMask(0).find_first_elem();
75}
76
77//=============================================================================
78//-----------------------------hash--------------------------------------------
79uint FastLockNode::hash() const { return NO_HASH; }
80
81//------------------------------cmp--------------------------------------------
82uint FastLockNode::cmp( const Node &n ) const {
83  return (&n == this);                // Always fail except on self
84}
85
86//=============================================================================
87//-----------------------------hash--------------------------------------------
88uint FastUnlockNode::hash() const { return NO_HASH; }
89
90//------------------------------cmp--------------------------------------------
91uint FastUnlockNode::cmp( const Node &n ) const {
92  return (&n == this);                // Always fail except on self
93}
94
95//
96// Create a counter which counts the number of times this lock is acquired
97//
98void FastLockNode::create_lock_counter(JVMState* state) {
99  BiasedLockingNamedCounter* blnc = (BiasedLockingNamedCounter*)
100           OptoRuntime::new_named_counter(state, NamedCounter::BiasedLockingCounter);
101  _counters = blnc->counters();
102}
103
104//=============================================================================
105//------------------------------do_monitor_enter-------------------------------
106void Parse::do_monitor_enter() {
107  kill_dead_locals();
108
109  // Null check; get casted pointer.
110  Node *obj = do_null_check(peek(), T_OBJECT);
111  // Check for locking null object
112  if (stopped()) return;
113
114  // the monitor object is not part of debug info expression stack
115  pop();
116
117  // Insert a FastLockNode which takes as arguments the current thread pointer,
118  // the obj pointer & the address of the stack slot pair used for the lock.
119  shared_lock(obj);
120}
121
122//------------------------------do_monitor_exit--------------------------------
123void Parse::do_monitor_exit() {
124  kill_dead_locals();
125
126  pop();                        // Pop oop to unlock
127  // Because monitors are guaranteed paired (else we bail out), we know
128  // the matching Lock for this Unlock.  Hence we know there is no need
129  // for a null check on Unlock.
130  shared_unlock(map()->peek_monitor_box(), map()->peek_monitor_obj());
131}
132