duke@435: /*
mikael@4153:  * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
stefank@2314: #include "precompiled.hpp"
stefank@2314: #include "opto/locknode.hpp"
stefank@2314: #include "opto/parse.hpp"
stefank@2314: #include "opto/rootnode.hpp"
stefank@2314: #include "opto/runtime.hpp"
duke@435: 
duke@435: //=============================================================================
duke@435: const RegMask &BoxLockNode::in_RegMask(uint i) const {
duke@435:   return _inmask;
duke@435: }
duke@435: 
duke@435: const RegMask &BoxLockNode::out_RegMask() const {
duke@435:   return *Matcher::idealreg2regmask[Op_RegP];
duke@435: }
duke@435: 
duke@435: uint BoxLockNode::size_of() const { return sizeof(*this); }
duke@435: 
kvn@501: BoxLockNode::BoxLockNode( int slot ) : Node( Compile::current()->root() ),
kvn@501:                                        _slot(slot), _is_eliminated(false) {
duke@435:   init_class_id(Class_BoxLock);
duke@435:   init_flags(Flag_rematerialize);
duke@435:   OptoReg::Name reg = OptoReg::stack2reg(_slot);
duke@435:   _inmask.Insert(reg);
duke@435: }
duke@435: 
kvn@895: //-----------------------------hash--------------------------------------------
kvn@895: uint BoxLockNode::hash() const {
kvn@3406:   if (EliminateNestedLocks)
kvn@3406:     return NO_HASH; // Each locked region has own BoxLock node
kvn@895:   return Node::hash() + _slot + (_is_eliminated ? Compile::current()->fixed_slots() : 0);
kvn@895: }
kvn@895: 
duke@435: //------------------------------cmp--------------------------------------------
duke@435: uint BoxLockNode::cmp( const Node &n ) const {
kvn@3406:   if (EliminateNestedLocks)
kvn@3406:     return (&n == this); // Always fail except on self
duke@435:   const BoxLockNode &bn = (const BoxLockNode &)n;
kvn@895:   return bn._slot == _slot && bn._is_eliminated == _is_eliminated;
duke@435: }
duke@435: 
kvn@3406: BoxLockNode* BoxLockNode::box_node(Node* box) {
kvn@3419:   // Chase down the BoxNode after RA which may spill box nodes.
kvn@3406:   while (!box->is_BoxLock()) {
duke@435:     //    if (box_node->is_SpillCopy()) {
duke@435:     //      Node *m = box_node->in(1);
duke@435:     //      if (m->is_Mach() && m->as_Mach()->ideal_Opcode() == Op_StoreP) {
duke@435:     //        box_node = m->in(m->as_Mach()->operand_index(2));
duke@435:     //        continue;
duke@435:     //      }
duke@435:     //    }
kvn@3406:     assert(box->is_SpillCopy() || box->is_Phi(), "Bad spill of Lock.");
kvn@3406:     // Only BoxLock nodes with the same stack slot are merged.
kvn@3406:     // So it is enough to trace one path to find the slot value.
kvn@3406:     box = box->in(1);
duke@435:   }
kvn@3406:   return box->as_BoxLock();
kvn@3406: }
kvn@3406: 
kvn@3406: OptoReg::Name BoxLockNode::reg(Node* box) {
kvn@3406:   return box_node(box)->in_RegMask(0).find_first_elem();
kvn@3406: }
kvn@3406: 
kvn@3406: // Is BoxLock node used for one simple lock region (same box and obj)?
kvn@3406: bool BoxLockNode::is_simple_lock_region(LockNode** unique_lock, Node* obj) {
kvn@3406:   LockNode* lock = NULL;
kvn@3406:   bool has_one_lock = false;
kvn@3406:   for (uint i = 0; i < this->outcnt(); i++) {
kvn@3406:     Node* n = this->raw_out(i);
kvn@3419:     assert(!n->is_Phi(), "should not merge BoxLock nodes");
kvn@3406:     if (n->is_AbstractLock()) {
kvn@3406:       AbstractLockNode* alock = n->as_AbstractLock();
kvn@3406:       // Check lock's box since box could be referenced by Lock's debug info.
kvn@3406:       if (alock->box_node() == this) {
kvn@3407:         if (alock->obj_node()->eqv_uncast(obj)) {
kvn@3406:           if ((unique_lock != NULL) && alock->is_Lock()) {
kvn@3406:             if (lock == NULL) {
kvn@3406:               lock = alock->as_Lock();
kvn@3406:               has_one_lock = true;
kvn@3406:             } else if (lock != alock->as_Lock()) {
kvn@3406:               has_one_lock = false;
kvn@3406:             }
kvn@3406:           }
kvn@3406:         } else {
kvn@3406:           return false; // Different objects
kvn@3406:         }
kvn@3406:       }
kvn@3406:     }
kvn@3406:   }
kvn@3406: #ifdef ASSERT
kvn@3406:   // Verify that FastLock and Safepoint reference only this lock region.
kvn@3406:   for (uint i = 0; i < this->outcnt(); i++) {
kvn@3406:     Node* n = this->raw_out(i);
kvn@3406:     if (n->is_FastLock()) {
kvn@3406:       FastLockNode* flock = n->as_FastLock();
kvn@3407:       assert((flock->box_node() == this) && flock->obj_node()->eqv_uncast(obj),"");
kvn@3406:     }
kvn@3421:     // Don't check monitor info in safepoints since the referenced object could
kvn@3421:     // be different from the locked object. It could be Phi node of different
kvn@3421:     // cast nodes which point to this locked object.
kvn@3421:     // We assume that no other objects could be referenced in monitor info
kvn@3421:     // associated with this BoxLock node because all associated locks and
kvn@3421:     // unlocks are reference only this one object.
kvn@3406:   }
kvn@3406: #endif
kvn@3406:   if (unique_lock != NULL && has_one_lock) {
kvn@3406:     *unique_lock = lock;
kvn@3406:   }
kvn@3406:   return true;
duke@435: }
duke@435: 
duke@435: //=============================================================================
duke@435: //-----------------------------hash--------------------------------------------
duke@435: uint FastLockNode::hash() const { return NO_HASH; }
duke@435: 
duke@435: //------------------------------cmp--------------------------------------------
duke@435: uint FastLockNode::cmp( const Node &n ) const {
duke@435:   return (&n == this);                // Always fail except on self
duke@435: }
duke@435: 
duke@435: //=============================================================================
duke@435: //-----------------------------hash--------------------------------------------
duke@435: uint FastUnlockNode::hash() const { return NO_HASH; }
duke@435: 
duke@435: //------------------------------cmp--------------------------------------------
duke@435: uint FastUnlockNode::cmp( const Node &n ) const {
duke@435:   return (&n == this);                // Always fail except on self
duke@435: }
duke@435: 
duke@435: //
duke@435: // Create a counter which counts the number of times this lock is acquired
duke@435: //
duke@435: void FastLockNode::create_lock_counter(JVMState* state) {
duke@435:   BiasedLockingNamedCounter* blnc = (BiasedLockingNamedCounter*)
duke@435:            OptoRuntime::new_named_counter(state, NamedCounter::BiasedLockingCounter);
duke@435:   _counters = blnc->counters();
duke@435: }
duke@435: 
duke@435: //=============================================================================
duke@435: //------------------------------do_monitor_enter-------------------------------
duke@435: void Parse::do_monitor_enter() {
duke@435:   kill_dead_locals();
duke@435: 
duke@435:   // Null check; get casted pointer.
twisti@4313:   Node* obj = null_check(peek());
duke@435:   // Check for locking null object
duke@435:   if (stopped()) return;
duke@435: 
duke@435:   // the monitor object is not part of debug info expression stack
duke@435:   pop();
duke@435: 
duke@435:   // Insert a FastLockNode which takes as arguments the current thread pointer,
duke@435:   // the obj pointer & the address of the stack slot pair used for the lock.
duke@435:   shared_lock(obj);
duke@435: }
duke@435: 
duke@435: //------------------------------do_monitor_exit--------------------------------
duke@435: void Parse::do_monitor_exit() {
duke@435:   kill_dead_locals();
duke@435: 
duke@435:   pop();                        // Pop oop to unlock
twisti@1040:   // Because monitors are guaranteed paired (else we bail out), we know
duke@435:   // the matching Lock for this Unlock.  Hence we know there is no need
duke@435:   // for a null check on Unlock.
duke@435:   shared_unlock(map()->peek_monitor_box(), map()->peek_monitor_obj());
duke@435: }