Wed, 06 Jan 2010 22:21:39 -0800
Merge
1 /*
2 * Copyright 1997-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 // oopDesc is the top baseclass for objects classes. The {name}Desc classes describe
26 // the format of Java objects so the fields can be accessed from C++.
27 // oopDesc is abstract.
28 // (see oopHierarchy for complete oop class hierarchy)
29 //
30 // no virtual functions allowed
32 // store into oop with store check
33 template <class T> inline void oop_store(T* p, oop v);
34 template <class T> inline void oop_store(volatile T* p, oop v);
36 // store into oop without store check
37 template <class T> inline void oop_store_without_check(T* p, oop v);
38 template <class T> inline void oop_store_without_check(volatile T* p, oop v);
40 extern bool always_do_update_barrier;
42 // Forward declarations.
43 class OopClosure;
44 class ScanClosure;
45 class FastScanClosure;
46 class FilteringClosure;
47 class BarrierSet;
48 class CMSIsAliveClosure;
50 class PSPromotionManager;
51 class ParCompactionManager;
53 class oopDesc {
54 friend class VMStructs;
55 private:
56 volatile markOop _mark;
57 union _metadata {
58 wideKlassOop _klass;
59 narrowOop _compressed_klass;
60 } _metadata;
62 // Fast access to barrier set. Must be initialized.
63 static BarrierSet* _bs;
65 public:
66 markOop mark() const { return _mark; }
67 markOop* mark_addr() const { return (markOop*) &_mark; }
69 void set_mark(volatile markOop m) { _mark = m; }
71 void release_set_mark(markOop m);
72 markOop cas_set_mark(markOop new_mark, markOop old_mark);
74 // Used only to re-initialize the mark word (e.g., of promoted
75 // objects during a GC) -- requires a valid klass pointer
76 void init_mark();
78 klassOop klass() const;
79 klassOop klass_or_null() const volatile;
80 oop* klass_addr();
81 narrowOop* compressed_klass_addr();
83 void set_klass(klassOop k);
85 // For klass field compression
86 int klass_gap() const;
87 void set_klass_gap(int z);
88 // For when the klass pointer is being used as a linked list "next" field.
89 void set_klass_to_list_ptr(oop k);
91 // size of object header, aligned to platform wordSize
92 static int header_size() { return sizeof(oopDesc)/HeapWordSize; }
94 Klass* blueprint() const;
96 // Returns whether this is an instance of k or an instance of a subclass of k
97 bool is_a(klassOop k) const;
99 // Returns the actual oop size of the object
100 int size();
102 // Sometimes (for complicated concurrency-related reasons), it is useful
103 // to be able to figure out the size of an object knowing its klass.
104 int size_given_klass(Klass* klass);
106 // Some perm gen objects are not parseble immediately after
107 // installation of their klass pointer.
108 bool is_parsable();
110 // Some perm gen objects that have been allocated and initialized
111 // can be changed by the VM when not at a safe point (class rededfinition
112 // is an example). Such objects should not be examined by the
113 // concurrent processing of a garbage collector if is_conc_safe()
114 // returns false.
115 bool is_conc_safe();
117 // type test operations (inlined in oop.inline.h)
118 bool is_instance() const;
119 bool is_instanceRef() const;
120 bool is_array() const;
121 bool is_objArray() const;
122 bool is_symbol() const;
123 bool is_klass() const;
124 bool is_thread() const;
125 bool is_method() const;
126 bool is_constMethod() const;
127 bool is_methodData() const;
128 bool is_constantPool() const;
129 bool is_constantPoolCache() const;
130 bool is_typeArray() const;
131 bool is_javaArray() const;
132 bool is_compiledICHolder() const;
134 private:
135 // field addresses in oop
136 void* field_base(int offset) const;
138 jbyte* byte_field_addr(int offset) const;
139 jchar* char_field_addr(int offset) const;
140 jboolean* bool_field_addr(int offset) const;
141 jint* int_field_addr(int offset) const;
142 jshort* short_field_addr(int offset) const;
143 jlong* long_field_addr(int offset) const;
144 jfloat* float_field_addr(int offset) const;
145 jdouble* double_field_addr(int offset) const;
146 address* address_field_addr(int offset) const;
148 public:
149 // Need this as public for garbage collection.
150 template <class T> T* obj_field_addr(int offset) const;
152 // Oop encoding heap max
153 static const uint64_t OopEncodingHeapMax =
154 (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
156 static bool is_null(oop obj);
157 static bool is_null(narrowOop obj);
159 // Decode an oop pointer from a narrowOop if compressed.
160 // These are overloaded for oop and narrowOop as are the other functions
161 // below so that they can be called in template functions.
162 static oop decode_heap_oop_not_null(oop v);
163 static oop decode_heap_oop_not_null(narrowOop v);
164 static oop decode_heap_oop(oop v);
165 static oop decode_heap_oop(narrowOop v);
167 // Encode an oop pointer to a narrow oop. The or_null versions accept
168 // null oop pointer, others do not in order to eliminate the
169 // null checking branches.
170 static narrowOop encode_heap_oop_not_null(oop v);
171 static narrowOop encode_heap_oop(oop v);
173 // Load an oop out of the Java heap
174 static narrowOop load_heap_oop(narrowOop* p);
175 static oop load_heap_oop(oop* p);
177 // Load an oop out of Java heap and decode it to an uncompressed oop.
178 static oop load_decode_heap_oop_not_null(narrowOop* p);
179 static oop load_decode_heap_oop_not_null(oop* p);
180 static oop load_decode_heap_oop(narrowOop* p);
181 static oop load_decode_heap_oop(oop* p);
183 // Store an oop into the heap.
184 static void store_heap_oop(narrowOop* p, narrowOop v);
185 static void store_heap_oop(oop* p, oop v);
187 // Encode oop if UseCompressedOops and store into the heap.
188 static void encode_store_heap_oop_not_null(narrowOop* p, oop v);
189 static void encode_store_heap_oop_not_null(oop* p, oop v);
190 static void encode_store_heap_oop(narrowOop* p, oop v);
191 static void encode_store_heap_oop(oop* p, oop v);
193 static void release_store_heap_oop(volatile narrowOop* p, narrowOop v);
194 static void release_store_heap_oop(volatile oop* p, oop v);
196 static void release_encode_store_heap_oop_not_null(volatile narrowOop* p, oop v);
197 static void release_encode_store_heap_oop_not_null(volatile oop* p, oop v);
198 static void release_encode_store_heap_oop(volatile narrowOop* p, oop v);
199 static void release_encode_store_heap_oop(volatile oop* p, oop v);
201 static oop atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest);
202 static oop atomic_compare_exchange_oop(oop exchange_value,
203 volatile HeapWord *dest,
204 oop compare_value);
206 // Access to fields in a instanceOop through these methods.
207 oop obj_field(int offset) const;
208 void obj_field_put(int offset, oop value);
209 void obj_field_raw_put(int offset, oop value);
211 jbyte byte_field(int offset) const;
212 void byte_field_put(int offset, jbyte contents);
214 jchar char_field(int offset) const;
215 void char_field_put(int offset, jchar contents);
217 jboolean bool_field(int offset) const;
218 void bool_field_put(int offset, jboolean contents);
220 jint int_field(int offset) const;
221 void int_field_put(int offset, jint contents);
223 jshort short_field(int offset) const;
224 void short_field_put(int offset, jshort contents);
226 jlong long_field(int offset) const;
227 void long_field_put(int offset, jlong contents);
229 jfloat float_field(int offset) const;
230 void float_field_put(int offset, jfloat contents);
232 jdouble double_field(int offset) const;
233 void double_field_put(int offset, jdouble contents);
235 address address_field(int offset) const;
236 void address_field_put(int offset, address contents);
238 oop obj_field_acquire(int offset) const;
239 void release_obj_field_put(int offset, oop value);
241 jbyte byte_field_acquire(int offset) const;
242 void release_byte_field_put(int offset, jbyte contents);
244 jchar char_field_acquire(int offset) const;
245 void release_char_field_put(int offset, jchar contents);
247 jboolean bool_field_acquire(int offset) const;
248 void release_bool_field_put(int offset, jboolean contents);
250 jint int_field_acquire(int offset) const;
251 void release_int_field_put(int offset, jint contents);
253 jshort short_field_acquire(int offset) const;
254 void release_short_field_put(int offset, jshort contents);
256 jlong long_field_acquire(int offset) const;
257 void release_long_field_put(int offset, jlong contents);
259 jfloat float_field_acquire(int offset) const;
260 void release_float_field_put(int offset, jfloat contents);
262 jdouble double_field_acquire(int offset) const;
263 void release_double_field_put(int offset, jdouble contents);
265 address address_field_acquire(int offset) const;
266 void release_address_field_put(int offset, address contents);
268 // printing functions for VM debugging
269 void print_on(outputStream* st) const; // First level print
270 void print_value_on(outputStream* st) const; // Second level print.
271 void print_address_on(outputStream* st) const; // Address printing
273 // printing on default output stream
274 void print();
275 void print_value();
276 void print_address();
278 // return the print strings
279 char* print_string();
280 char* print_value_string();
282 // verification operations
283 void verify_on(outputStream* st);
284 void verify();
285 void verify_old_oop(oop* p, bool allow_dirty);
286 void verify_old_oop(narrowOop* p, bool allow_dirty);
288 // tells whether this oop is partially constructed (gc during class loading)
289 bool partially_loaded();
290 void set_partially_loaded();
292 // locking operations
293 bool is_locked() const;
294 bool is_unlocked() const;
295 bool has_bias_pattern() const;
297 // asserts
298 bool is_oop(bool ignore_mark_word = false) const;
299 bool is_oop_or_null(bool ignore_mark_word = false) const;
300 #ifndef PRODUCT
301 bool is_unlocked_oop() const;
302 #endif
304 // garbage collection
305 bool is_gc_marked() const;
306 // Apply "MarkSweep::mark_and_push" to (the address of) every non-NULL
307 // reference field in "this".
308 void follow_contents(void);
309 void follow_header(void);
311 #ifndef SERIALGC
312 // Parallel Scavenge
313 void copy_contents(PSPromotionManager* pm);
314 void push_contents(PSPromotionManager* pm);
316 // Parallel Old
317 void update_contents(ParCompactionManager* cm);
318 void update_contents(ParCompactionManager* cm,
319 HeapWord* begin_limit,
320 HeapWord* end_limit);
321 void update_contents(ParCompactionManager* cm,
322 klassOop old_klass,
323 HeapWord* begin_limit,
324 HeapWord* end_limit);
326 void follow_contents(ParCompactionManager* cm);
327 void follow_header(ParCompactionManager* cm);
328 #endif // SERIALGC
330 bool is_perm() const;
331 bool is_perm_or_null() const;
332 bool is_scavengable() const;
333 bool is_shared() const;
334 bool is_shared_readonly() const;
335 bool is_shared_readwrite() const;
337 // Forward pointer operations for scavenge
338 bool is_forwarded() const;
340 void forward_to(oop p);
341 bool cas_forward_to(oop p, markOop compare);
343 #ifndef SERIALGC
344 // Like "forward_to", but inserts the forwarding pointer atomically.
345 // Exactly one thread succeeds in inserting the forwarding pointer, and
346 // this call returns "NULL" for that thread; any other thread has the
347 // value of the forwarding pointer returned and does not modify "this".
348 oop forward_to_atomic(oop p);
349 #endif // SERIALGC
351 oop forwardee() const;
353 // Age of object during scavenge
354 int age() const;
355 void incr_age();
357 // Adjust all pointers in this object to point at it's forwarded location and
358 // return the size of this oop. This is used by the MarkSweep collector.
359 int adjust_pointers();
360 void adjust_header();
362 #ifndef SERIALGC
363 // Parallel old
364 void update_header();
365 void update_header(HeapWord* beg_addr, HeapWord* end_addr);
366 #endif // SERIALGC
368 // mark-sweep support
369 void follow_body(int begin, int end);
371 // Fast access to barrier set
372 static BarrierSet* bs() { return _bs; }
373 static void set_bs(BarrierSet* bs) { _bs = bs; }
375 // iterators, returns size of object
376 #define OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
377 int oop_iterate(OopClosureType* blk); \
378 int oop_iterate(OopClosureType* blk, MemRegion mr); // Only in mr.
380 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DECL)
381 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DECL)
383 #ifndef SERIALGC
385 #define OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
386 int oop_iterate_backwards(OopClosureType* blk);
388 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DECL)
389 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DECL)
390 #endif
392 void oop_iterate_header(OopClosure* blk);
393 void oop_iterate_header(OopClosure* blk, MemRegion mr);
395 // identity hash; returns the identity hash key (computes it if necessary)
396 // NOTE with the introduction of UseBiasedLocking that identity_hash() might reach a
397 // safepoint if called on a biased object. Calling code must be aware of that.
398 intptr_t identity_hash();
399 intptr_t slow_identity_hash();
401 // marks are forwarded to stack when object is locked
402 bool has_displaced_mark() const;
403 markOop displaced_mark() const;
404 void set_displaced_mark(markOop m);
406 // for code generation
407 static int mark_offset_in_bytes() { return offset_of(oopDesc, _mark); }
408 static int klass_offset_in_bytes() { return offset_of(oopDesc, _metadata._klass); }
409 static int klass_gap_offset_in_bytes();
410 };