duke@435: /*
coleenp@4037:  * Copyright (c) 1998, 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: #ifndef SHARE_VM_OOPS_COMPILEDICHOLDEROOP_HPP
stefank@2314: #define SHARE_VM_OOPS_COMPILEDICHOLDEROOP_HPP
stefank@2314: 
stefank@2314: #include "oops/oop.hpp"
stefank@2314: 
coleenp@4037: // A CompiledICHolder* is a helper object for the inline cache implementation.
duke@435: // It holds an intermediate value (method+klass pair) used when converting from
duke@435: // compiled to an interpreted call.
duke@435: //
coleenp@4037: // These are always allocated in the C heap and are freed during a
coleenp@4037: // safepoint by the ICBuffer logic.  It's unsafe to free them earlier
coleenp@4037: // since they might be in use.
coleenp@4037: //
duke@435: 
duke@435: 
coleenp@4037: class CompiledICHolder : public CHeapObj<mtCompiler> {
duke@435:   friend class VMStructs;
duke@435:  private:
coleenp@4037:   static volatile int _live_count; // allocated
coleenp@4037:   static volatile int _live_not_claimed_count; // allocated but not yet in use so not
coleenp@4037:                                                // reachable by iterating over nmethods
coleenp@4037: 
coleenp@4037:   Method* _holder_method;
coleenp@4037:   Klass*    _holder_klass;    // to avoid name conflict with oopDesc::_klass
coleenp@4037:   CompiledICHolder* _next;
coleenp@4037: 
duke@435:  public:
coleenp@4037:   // Constructor
coleenp@4037:   CompiledICHolder(Method* method, Klass* klass)
coleenp@4037:       : _holder_method(method), _holder_klass(klass) {
coleenp@4037: #ifdef ASSERT
coleenp@4037:     Atomic::inc(&_live_count);
coleenp@4037:     Atomic::inc(&_live_not_claimed_count);
coleenp@4037: #endif
coleenp@4037:   }
coleenp@4037: 
coleenp@4037:   ~CompiledICHolder() {
coleenp@4037: #ifdef ASSERT
coleenp@4037:     assert(_live_count > 0, "underflow");
coleenp@4037:     Atomic::dec(&_live_count);
coleenp@4037: #endif
coleenp@4037:   }
coleenp@4037: 
coleenp@4037:   static int live_count() { return _live_count; }
coleenp@4037:   static int live_not_claimed_count() { return _live_not_claimed_count; }
coleenp@4037: 
duke@435:   // accessors
coleenp@4037:   Method* holder_method() const     { return _holder_method; }
coleenp@4037:   Klass*    holder_klass()  const     { return _holder_klass; }
duke@435: 
coleenp@4037:   void set_holder_method(Method* m) { _holder_method = m; }
coleenp@4037:   void set_holder_klass(Klass* k)   { _holder_klass = k; }
duke@435: 
duke@435:   // interpreter support (offsets in bytes)
coleenp@4037:   static int holder_method_offset()   { return offset_of(CompiledICHolder, _holder_method); }
coleenp@4037:   static int holder_klass_offset()    { return offset_of(CompiledICHolder, _holder_klass); }
duke@435: 
coleenp@4037:   CompiledICHolder* next()     { return _next; }
coleenp@4037:   void set_next(CompiledICHolder* n) { _next = n; }
coleenp@4037: 
coleenp@4037:   // Verify
coleenp@4037:   void verify_on(outputStream* st);
coleenp@4037: 
coleenp@4037:   // Printing
coleenp@4037:   void print_on(outputStream* st) const;
coleenp@4037:   void print_value_on(outputStream* st) const;
coleenp@4037: 
coleenp@4037:   const char* internal_name() const { return "{compiledICHolder}"; }
coleenp@4037: 
coleenp@4037:   void claim() {
coleenp@4037: #ifdef ASSERT
coleenp@4037:     Atomic::dec(&_live_not_claimed_count);
coleenp@4037: #endif
coleenp@4037:   }
duke@435: };
stefank@2314: 
stefank@2314: #endif // SHARE_VM_OOPS_COMPILEDICHOLDEROOP_HPP