1 /*
  2  * Copyright (c) 2017, 2019, 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 #include "precompiled.hpp"
 25 #include "gc/z/zLock.inline.hpp"
 26 #include "gc/z/zNMethodData.hpp"
 27 #include "memory/allocation.hpp"
 28 #include "runtime/atomic.hpp"
 29 #include "runtime/orderAccess.hpp"
 30 #include "utilities/align.hpp"
 31 #include "utilities/debug.hpp"
 32 #include "utilities/globalCounter.inline.hpp"
 33 #include "utilities/growableArray.hpp"
 34 
 35 size_t ZNMethodDataOops::header_size() {
 36   const size_t size = sizeof(ZNMethodDataOops);
 37   assert(is_aligned(size, sizeof(oop*)), "Header misaligned");
 38   return size;
 39 }
 40 
 41 ZNMethodDataOops* ZNMethodDataOops::create(const GrowableArray<oop*>& immediates, bool has_non_immediates) {
 42   // Allocate memory for the ZNMethodDataOops object
 43   // plus the immediate oop* array that follows right after.
 44   const size_t size = ZNMethodDataOops::header_size() + (sizeof(oop*) * immediates.length());
 45   void* const mem = NEW_C_HEAP_ARRAY(uint8_t, size, mtGC);
 46   return ::new (mem) ZNMethodDataOops(immediates, has_non_immediates);
 47 }
 48 
 49 void ZNMethodDataOops::destroy(ZNMethodDataOops* oops) {
 50   FREE_C_HEAP_ARRAY(uint8_t, oops);
 51 }
 52 
 53 ZNMethodDataOops::ZNMethodDataOops(const GrowableArray<oop*>& immediates, bool has_non_immediates) :
 54     _nimmediates(immediates.length()),
 55     _has_non_immediates(has_non_immediates) {
 56   // Save all immediate oops
 57   for (size_t i = 0; i < _nimmediates; i++) {
 58     immediates_begin()[i] = immediates.at(i);
 59   }
 60 }
 61 
 62 size_t ZNMethodDataOops::immediates_count() const {
 63   return _nimmediates;
 64 }
 65 
 66 oop** ZNMethodDataOops::immediates_begin() const {
 67   // The immediate oop* array starts immediately after this object
 68   return (oop**)((uintptr_t)this + header_size());
 69 }
 70 
 71 oop** ZNMethodDataOops::immediates_end() const {
 72   return immediates_begin() + immediates_count();
 73 }
 74 
 75 bool ZNMethodDataOops::has_non_immediates() const {
 76   return _has_non_immediates;
 77 }
 78 
 79 ZNMethodData::ZNMethodData() :
 80     _lock(),
 81     _oops(NULL) {}
 82 
 83 ZNMethodData::~ZNMethodData() {
 84   ZNMethodDataOops::destroy(_oops);
 85 }
 86 
 87 ZReentrantLock* ZNMethodData::lock() {
 88   return &_lock;
 89 }
 90 
 91 ZNMethodDataOops* ZNMethodData::oops() const {
 92   return OrderAccess::load_acquire(&_oops);
 93 }
 94 
 95 ZNMethodDataOops* ZNMethodData::swap_oops(ZNMethodDataOops* new_oops) {
 96   ZNMethodDataOops* const oops = Atomic::xchg(new_oops, &_oops);
 97   if (oops != NULL) {
 98     GlobalCounter::write_synchronize();
 99   }
100   return oops;
101 }