Thu, 26 Jun 2014 11:36:58 +0200
8047818: G1 HeapRegions can no longer be ContiguousSpaces
Summary: Change parent of G1OffsetTableContigSpace to CompactibleSpace, reimplement missing functionality
Reviewed-by: stefank, jmasa, tschatzl
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25 #ifndef SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP
26 #define SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP
28 #include "memory/cardTableRS.hpp"
29 #include "memory/defNewGeneration.hpp"
30 #include "memory/genCollectedHeap.hpp"
31 #include "memory/genOopClosures.hpp"
32 #include "memory/genRemSet.hpp"
33 #include "memory/generation.hpp"
34 #include "memory/sharedHeap.hpp"
35 #include "memory/space.hpp"
37 inline OopsInGenClosure::OopsInGenClosure(Generation* gen) :
38 ExtendedOopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) {
39 set_generation(gen);
40 }
42 inline void OopsInGenClosure::set_generation(Generation* gen) {
43 _gen = gen;
44 _gen_boundary = _gen->reserved().start();
45 // Barrier set for the heap, must be set after heap is initialized
46 if (_rs == NULL) {
47 GenRemSet* rs = SharedHeap::heap()->rem_set();
48 assert(rs->rs_kind() == GenRemSet::CardTable, "Wrong rem set kind");
49 _rs = (CardTableRS*)rs;
50 }
51 }
53 template <class T> inline void OopsInGenClosure::do_barrier(T* p) {
54 assert(generation()->is_in_reserved(p), "expected ref in generation");
55 T heap_oop = oopDesc::load_heap_oop(p);
56 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
57 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
58 // If p points to a younger generation, mark the card.
59 if ((HeapWord*)obj < _gen_boundary) {
60 _rs->inline_write_ref_field_gc(p, obj);
61 }
62 }
64 template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) {
65 assert(generation()->is_in_reserved(p), "expected ref in generation");
66 T heap_oop = oopDesc::load_heap_oop(p);
67 assert(!oopDesc::is_null(heap_oop), "expected non-null oop");
68 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
69 // If p points to a younger generation, mark the card.
70 if ((HeapWord*)obj < gen_boundary()) {
71 rs()->write_ref_field_gc_par(p, obj);
72 }
73 }
75 inline void OopsInKlassOrGenClosure::do_klass_barrier() {
76 assert(_scanned_klass != NULL, "Must be");
77 _scanned_klass->record_modified_oops();
78 }
80 // NOTE! Any changes made here should also be made
81 // in FastScanClosure::do_oop_work()
82 template <class T> inline void ScanClosure::do_oop_work(T* p) {
83 T heap_oop = oopDesc::load_heap_oop(p);
84 // Should we copy the obj?
85 if (!oopDesc::is_null(heap_oop)) {
86 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
87 if ((HeapWord*)obj < _boundary) {
88 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
89 oop new_obj = obj->is_forwarded() ? obj->forwardee()
90 : _g->copy_to_survivor_space(obj);
91 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
92 }
94 if (is_scanning_a_klass()) {
95 do_klass_barrier();
96 } else if (_gc_barrier) {
97 // Now call parent closure
98 do_barrier(p);
99 }
100 }
101 }
103 inline void ScanClosure::do_oop_nv(oop* p) { ScanClosure::do_oop_work(p); }
104 inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); }
106 // NOTE! Any changes made here should also be made
107 // in ScanClosure::do_oop_work()
108 template <class T> inline void FastScanClosure::do_oop_work(T* p) {
109 T heap_oop = oopDesc::load_heap_oop(p);
110 // Should we copy the obj?
111 if (!oopDesc::is_null(heap_oop)) {
112 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
113 if ((HeapWord*)obj < _boundary) {
114 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
115 oop new_obj = obj->is_forwarded() ? obj->forwardee()
116 : _g->copy_to_survivor_space(obj);
117 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
118 if (is_scanning_a_klass()) {
119 do_klass_barrier();
120 } else if (_gc_barrier) {
121 // Now call parent closure
122 do_barrier(p);
123 }
124 }
125 }
126 }
128 inline void FastScanClosure::do_oop_nv(oop* p) { FastScanClosure::do_oop_work(p); }
129 inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); }
131 // Note similarity to ScanClosure; the difference is that
132 // the barrier set is taken care of outside this closure.
133 template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) {
134 assert(!oopDesc::is_null(*p), "null weak reference?");
135 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
136 // weak references are sometimes scanned twice; must check
137 // that to-space doesn't already contain this object
138 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
139 oop new_obj = obj->is_forwarded() ? obj->forwardee()
140 : _g->copy_to_survivor_space(obj);
141 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
142 }
143 }
145 inline void ScanWeakRefClosure::do_oop_nv(oop* p) { ScanWeakRefClosure::do_oop_work(p); }
146 inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); }
148 #endif // SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP