1 /*
   2  * Copyright (c) 2000, 2013, 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 #ifndef SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_INLINE_HPP
  26 #define SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_INLINE_HPP
  27 
  28 #include "gc_implementation/shared/markSweep.hpp"
  29 #include "gc_interface/collectedHeap.hpp"
  30 #include "utilities/stack.inline.hpp"
  31 #include "utilities/macros.hpp"
  32 #if INCLUDE_ALL_GCS
  33 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
  34 #endif // INCLUDE_ALL_GCS
  35 
  36 inline void MarkSweep::mark_object(oop obj) {
  37   // some marks may contain information we need to preserve so we store them away
  38   // and overwrite the mark.  We'll restore it at the end of markSweep.
  39   markOop mark = obj->mark();
  40   obj->set_mark(markOopDesc::prototype()->set_marked());
  41 
  42   if (mark->must_be_preserved(obj)) {
  43     preserve_mark(obj, mark);
  44   }
  45 }
  46 
  47 inline void MarkSweep::follow_klass(Klass* klass) {
  48   oop op = klass->klass_holder();
  49   MarkSweep::mark_and_push(&op);
  50 }
  51 
  52 template <class T> inline void MarkSweep::follow_root(T* p) {
  53   assert(!Universe::heap()->is_in_reserved(p),
  54          "roots shouldn't be things within the heap");
  55   T heap_oop = oopDesc::load_heap_oop(p);
  56   if (!oopDesc::is_null(heap_oop)) {
  57     oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
  58     if (!obj->mark()->is_marked()) {
  59       mark_object(obj);
  60       obj->follow_contents();
  61     }
  62   }
  63   follow_stack();
  64 }
  65 
  66 template <class T> inline void MarkSweep::mark_and_push(T* p) {
  67 //  assert(Universe::heap()->is_in_reserved(p), "should be in object space");
  68   T heap_oop = oopDesc::load_heap_oop(p);
  69   if (!oopDesc::is_null(heap_oop)) {
  70     oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
  71     if (!obj->mark()->is_marked()) {
  72       mark_object(obj);
  73       _marking_stack.push(obj);
  74     }
  75   }
  76 }
  77 
  78 void MarkSweep::push_objarray(oop obj, size_t index) {
  79   ObjArrayTask task(obj, index);
  80   assert(task.is_valid(), "bad ObjArrayTask");
  81   _objarray_stack.push(task);
  82 }
  83 
  84 template <class T> inline void MarkSweep::adjust_pointer(T* p) {
  85   T heap_oop = oopDesc::load_heap_oop(p);
  86   if (!oopDesc::is_null(heap_oop)) {
  87     oop obj     = oopDesc::decode_heap_oop_not_null(heap_oop);
  88     oop new_obj = oop(obj->mark()->decode_pointer());
  89     assert(new_obj != NULL ||                         // is forwarding ptr?
  90            obj->mark() == markOopDesc::prototype() || // not gc marked?
  91            (UseBiasedLocking && obj->mark()->has_bias_pattern()),
  92                                                       // not gc marked?
  93            "should be forwarded");
  94     if (new_obj != NULL) {
  95       assert(Universe::heap()->is_in_reserved(new_obj),
  96              "should be in object space");
  97       oopDesc::encode_store_heap_oop_not_null(p, new_obj);
  98     }
  99   }
 100 }
 101 
 102 template <class T> inline void MarkSweep::KeepAliveClosure::do_oop_work(T* p) {
 103   mark_and_push(p);
 104 }
 105 
 106 #endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_INLINE_HPP