genOopClosures.inline.hpp revision 8413:92457dfb91bd 
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24
25#ifndef SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP
26#define SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP
27
28#include "gc/serial/defNewGeneration.hpp"
29#include "gc/shared/cardTableRS.hpp"
30#include "gc/shared/genCollectedHeap.hpp"
31#include "gc/shared/genOopClosures.hpp"
32#include "gc/shared/genRemSet.hpp"
33#include "gc/shared/generation.hpp"
34#include "gc/shared/space.hpp"
35
36inline OopsInGenClosure::OopsInGenClosure(Generation* gen) :
37  ExtendedOopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) {
38  set_generation(gen);
39}
40
41inline void OopsInGenClosure::set_generation(Generation* gen) {
42  _gen = gen;
43  _gen_boundary = _gen->reserved().start();
44  // Barrier set for the heap, must be set after heap is initialized
45  if (_rs == NULL) {
46    GenRemSet* rs = GenCollectedHeap::heap()->rem_set();
47    _rs = (CardTableRS*)rs;
48  }
49}
50
51template <class T> inline void OopsInGenClosure::do_barrier(T* p) {
52  assert(generation()->is_in_reserved(p), "expected ref in generation");
53  T heap_oop = oopDesc::load_heap_oop(p);
54  assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
55  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
56  // If p points to a younger generation, mark the card.
57  if ((HeapWord*)obj < _gen_boundary) {
58    _rs->inline_write_ref_field_gc(p, obj);
59  }
60}
61
62template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) {
63  assert(generation()->is_in_reserved(p), "expected ref in generation");
64  T heap_oop = oopDesc::load_heap_oop(p);
65  assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
66  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
67  // If p points to a younger generation, mark the card.
68  if ((HeapWord*)obj < gen_boundary()) {
69    rs()->write_ref_field_gc_par(p, obj);
70  }
71}
72
73inline void OopsInKlassOrGenClosure::do_klass_barrier() {
74  assert(_scanned_klass != NULL, "Must be");
75  _scanned_klass->record_modified_oops();
76}
77
78// NOTE! Any changes made here should also be made
79// in FastScanClosure::do_oop_work()
80template <class T> inline void ScanClosure::do_oop_work(T* p) {
81  T heap_oop = oopDesc::load_heap_oop(p);
82  // Should we copy the obj?
83  if (!oopDesc::is_null(heap_oop)) {
84    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
85    if ((HeapWord*)obj < _boundary) {
86      assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
87      oop new_obj = obj->is_forwarded() ? obj->forwardee()
88                                        : _g->copy_to_survivor_space(obj);
89      oopDesc::encode_store_heap_oop_not_null(p, new_obj);
90    }
91
92    if (is_scanning_a_klass()) {
93      do_klass_barrier();
94    } else if (_gc_barrier) {
95      // Now call parent closure
96      do_barrier(p);
97    }
98  }
99}
100
101inline void ScanClosure::do_oop_nv(oop* p)       { ScanClosure::do_oop_work(p); }
102inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); }
103
104// NOTE! Any changes made here should also be made
105// in ScanClosure::do_oop_work()
106template <class T> inline void FastScanClosure::do_oop_work(T* p) {
107  T heap_oop = oopDesc::load_heap_oop(p);
108  // Should we copy the obj?
109  if (!oopDesc::is_null(heap_oop)) {
110    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
111    if ((HeapWord*)obj < _boundary) {
112      assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
113      oop new_obj = obj->is_forwarded() ? obj->forwardee()
114                                        : _g->copy_to_survivor_space(obj);
115      oopDesc::encode_store_heap_oop_not_null(p, new_obj);
116      if (is_scanning_a_klass()) {
117        do_klass_barrier();
118      } else if (_gc_barrier) {
119        // Now call parent closure
120        do_barrier(p);
121      }
122    }
123  }
124}
125
126inline void FastScanClosure::do_oop_nv(oop* p)       { FastScanClosure::do_oop_work(p); }
127inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); }
128
129// Note similarity to ScanClosure; the difference is that
130// the barrier set is taken care of outside this closure.
131template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) {
132  assert(!oopDesc::is_null(*p), "null weak reference?");
133  oop obj = oopDesc::load_decode_heap_oop_not_null(p);
134  // weak references are sometimes scanned twice; must check
135  // that to-space doesn't already contain this object
136  if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
137    oop new_obj = obj->is_forwarded() ? obj->forwardee()
138                                      : _g->copy_to_survivor_space(obj);
139    oopDesc::encode_store_heap_oop_not_null(p, new_obj);
140  }
141}
142
143inline void ScanWeakRefClosure::do_oop_nv(oop* p)       { ScanWeakRefClosure::do_oop_work(p); }
144inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); }
145
146#endif // SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP
147