Fri, 16 Nov 2012 09:19:12 -0500
Merge
1 /*
2 * Copyright (c) 1997, 2012, 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.
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23 */
25 #ifndef SHARE_VM_OOPS_OOP_HPP
26 #define SHARE_VM_OOPS_OOP_HPP
28 #include "memory/iterator.hpp"
29 #include "memory/memRegion.hpp"
30 #include "memory/specialized_oop_closures.hpp"
31 #include "oops/metadata.hpp"
32 #include "utilities/top.hpp"
34 // oopDesc is the top baseclass for objects classes. The {name}Desc classes describe
35 // the format of Java objects so the fields can be accessed from C++.
36 // oopDesc is abstract.
37 // (see oopHierarchy for complete oop class hierarchy)
38 //
39 // no virtual functions allowed
41 // store into oop with store check
42 template <class T> void oop_store(T* p, oop v);
43 template <class T> void oop_store(volatile T* p, oop v);
45 extern bool always_do_update_barrier;
47 // Forward declarations.
48 class OopClosure;
49 class ScanClosure;
50 class FastScanClosure;
51 class FilteringClosure;
52 class BarrierSet;
53 class CMSIsAliveClosure;
55 class PSPromotionManager;
56 class ParCompactionManager;
58 class oopDesc {
59 friend class VMStructs;
60 private:
61 volatile markOop _mark;
62 union _metadata {
63 Klass* _klass;
64 narrowOop _compressed_klass;
65 } _metadata;
67 // Fast access to barrier set. Must be initialized.
68 static BarrierSet* _bs;
70 public:
71 markOop mark() const { return _mark; }
72 markOop* mark_addr() const { return (markOop*) &_mark; }
74 void set_mark(volatile markOop m) { _mark = m; }
76 void release_set_mark(markOop m);
77 markOop cas_set_mark(markOop new_mark, markOop old_mark);
79 // Used only to re-initialize the mark word (e.g., of promoted
80 // objects during a GC) -- requires a valid klass pointer
81 void init_mark();
83 Klass* klass() const;
84 Klass* klass_or_null() const volatile;
85 Klass** klass_addr();
86 narrowOop* compressed_klass_addr();
88 void set_klass(Klass* k);
90 // For klass field compression
91 int klass_gap() const;
92 void set_klass_gap(int z);
93 // For when the klass pointer is being used as a linked list "next" field.
94 void set_klass_to_list_ptr(oop k);
95 oop list_ptr_from_klass();
97 // size of object header, aligned to platform wordSize
98 static int header_size() { return sizeof(oopDesc)/HeapWordSize; }
100 // Returns whether this is an instance of k or an instance of a subclass of k
101 bool is_a(Klass* k) const;
103 // Returns the actual oop size of the object
104 int size();
106 // Sometimes (for complicated concurrency-related reasons), it is useful
107 // to be able to figure out the size of an object knowing its klass.
108 int size_given_klass(Klass* klass);
110 // type test operations (inlined in oop.inline.h)
111 bool is_instance() const;
112 bool is_instanceMirror() const;
113 bool is_instanceRef() const;
114 bool is_array() const;
115 bool is_objArray() const;
116 bool is_typeArray() const;
118 private:
119 // field addresses in oop
120 void* field_base(int offset) const;
122 jbyte* byte_field_addr(int offset) const;
123 jchar* char_field_addr(int offset) const;
124 jboolean* bool_field_addr(int offset) const;
125 jint* int_field_addr(int offset) const;
126 jshort* short_field_addr(int offset) const;
127 jlong* long_field_addr(int offset) const;
128 jfloat* float_field_addr(int offset) const;
129 jdouble* double_field_addr(int offset) const;
130 Metadata** metadata_field_addr(int offset) const;
132 public:
133 // Need this as public for garbage collection.
134 template <class T> T* obj_field_addr(int offset) const;
136 // Needed for javaClasses
137 address* address_field_addr(int offset) const;
139 static bool is_null(oop obj);
140 static bool is_null(narrowOop obj);
141 static bool is_null(Klass* obj);
143 // Decode an oop pointer from a narrowOop if compressed.
144 // These are overloaded for oop and narrowOop as are the other functions
145 // below so that they can be called in template functions.
146 static oop decode_heap_oop_not_null(oop v);
147 static oop decode_heap_oop_not_null(narrowOop v);
148 static oop decode_heap_oop(oop v);
149 static oop decode_heap_oop(narrowOop v);
151 // Encode an oop pointer to a narrow oop. The or_null versions accept
152 // null oop pointer, others do not in order to eliminate the
153 // null checking branches.
154 static narrowOop encode_heap_oop_not_null(oop v);
155 static narrowOop encode_heap_oop(oop v);
157 // Load an oop out of the Java heap
158 static narrowOop load_heap_oop(narrowOop* p);
159 static oop load_heap_oop(oop* p);
161 // Load an oop out of Java heap and decode it to an uncompressed oop.
162 static oop load_decode_heap_oop_not_null(narrowOop* p);
163 static oop load_decode_heap_oop_not_null(oop* p);
164 static oop load_decode_heap_oop(narrowOop* p);
165 static oop load_decode_heap_oop(oop* p);
167 // Store an oop into the heap.
168 static void store_heap_oop(narrowOop* p, narrowOop v);
169 static void store_heap_oop(oop* p, oop v);
171 // Encode oop if UseCompressedOops and store into the heap.
172 static void encode_store_heap_oop_not_null(narrowOop* p, oop v);
173 static void encode_store_heap_oop_not_null(oop* p, oop v);
174 static void encode_store_heap_oop(narrowOop* p, oop v);
175 static void encode_store_heap_oop(oop* p, oop v);
177 static void release_store_heap_oop(volatile narrowOop* p, narrowOop v);
178 static void release_store_heap_oop(volatile oop* p, oop v);
180 static void release_encode_store_heap_oop_not_null(volatile narrowOop* p, oop v);
181 static void release_encode_store_heap_oop_not_null(volatile oop* p, oop v);
182 static void release_encode_store_heap_oop(volatile narrowOop* p, oop v);
183 static void release_encode_store_heap_oop(volatile oop* p, oop v);
185 static oop atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest);
186 static oop atomic_compare_exchange_oop(oop exchange_value,
187 volatile HeapWord *dest,
188 oop compare_value,
189 bool prebarrier = false);
191 // klass encoding for klass pointer in objects.
192 static narrowOop encode_klass_not_null(Klass* v);
193 static narrowOop encode_klass(Klass* v);
195 static Klass* decode_klass_not_null(narrowOop v);
196 static Klass* decode_klass(narrowOop v);
198 // Access to fields in a instanceOop through these methods.
199 oop obj_field(int offset) const;
200 volatile oop obj_field_volatile(int offset) const;
201 void obj_field_put(int offset, oop value);
202 void obj_field_put_raw(int offset, oop value);
203 void obj_field_put_volatile(int offset, oop value);
205 Metadata* metadata_field(int offset) const;
206 void metadata_field_put(int offset, Metadata* value);
208 jbyte byte_field(int offset) const;
209 void byte_field_put(int offset, jbyte contents);
211 jchar char_field(int offset) const;
212 void char_field_put(int offset, jchar contents);
214 jboolean bool_field(int offset) const;
215 void bool_field_put(int offset, jboolean contents);
217 jint int_field(int offset) const;
218 void int_field_put(int offset, jint contents);
220 jshort short_field(int offset) const;
221 void short_field_put(int offset, jshort contents);
223 jlong long_field(int offset) const;
224 void long_field_put(int offset, jlong contents);
226 jfloat float_field(int offset) const;
227 void float_field_put(int offset, jfloat contents);
229 jdouble double_field(int offset) const;
230 void double_field_put(int offset, jdouble contents);
232 address address_field(int offset) const;
233 void address_field_put(int offset, address contents);
235 oop obj_field_acquire(int offset) const;
236 void release_obj_field_put(int offset, oop value);
238 jbyte byte_field_acquire(int offset) const;
239 void release_byte_field_put(int offset, jbyte contents);
241 jchar char_field_acquire(int offset) const;
242 void release_char_field_put(int offset, jchar contents);
244 jboolean bool_field_acquire(int offset) const;
245 void release_bool_field_put(int offset, jboolean contents);
247 jint int_field_acquire(int offset) const;
248 void release_int_field_put(int offset, jint contents);
250 jshort short_field_acquire(int offset) const;
251 void release_short_field_put(int offset, jshort contents);
253 jlong long_field_acquire(int offset) const;
254 void release_long_field_put(int offset, jlong contents);
256 jfloat float_field_acquire(int offset) const;
257 void release_float_field_put(int offset, jfloat contents);
259 jdouble double_field_acquire(int offset) const;
260 void release_double_field_put(int offset, jdouble contents);
262 address address_field_acquire(int offset) const;
263 void release_address_field_put(int offset, address contents);
265 // printing functions for VM debugging
266 void print_on(outputStream* st) const; // First level print
267 void print_value_on(outputStream* st) const; // Second level print.
268 void print_address_on(outputStream* st) const; // Address printing
270 // printing on default output stream
271 void print();
272 void print_value();
273 void print_address();
275 // return the print strings
276 char* print_string();
277 char* print_value_string();
279 // verification operations
280 void verify_on(outputStream* st);
281 void verify();
283 // locking operations
284 bool is_locked() const;
285 bool is_unlocked() const;
286 bool has_bias_pattern() const;
288 // asserts
289 bool is_oop(bool ignore_mark_word = false) const;
290 bool is_oop_or_null(bool ignore_mark_word = false) const;
291 #ifndef PRODUCT
292 bool is_unlocked_oop() const;
293 #endif
295 // garbage collection
296 bool is_gc_marked() const;
297 // Apply "MarkSweep::mark_and_push" to (the address of) every non-NULL
298 // reference field in "this".
299 void follow_contents(void);
301 #ifndef SERIALGC
302 // Parallel Scavenge
303 void push_contents(PSPromotionManager* pm);
305 // Parallel Old
306 void update_contents(ParCompactionManager* cm);
308 void follow_contents(ParCompactionManager* cm);
309 #endif // SERIALGC
311 bool is_scavengable() const;
313 // Forward pointer operations for scavenge
314 bool is_forwarded() const;
316 void forward_to(oop p);
317 bool cas_forward_to(oop p, markOop compare);
319 #ifndef SERIALGC
320 // Like "forward_to", but inserts the forwarding pointer atomically.
321 // Exactly one thread succeeds in inserting the forwarding pointer, and
322 // this call returns "NULL" for that thread; any other thread has the
323 // value of the forwarding pointer returned and does not modify "this".
324 oop forward_to_atomic(oop p);
325 #endif // SERIALGC
327 oop forwardee() const;
329 // Age of object during scavenge
330 uint age() const;
331 void incr_age();
333 // Adjust all pointers in this object to point at it's forwarded location and
334 // return the size of this oop. This is used by the MarkSweep collector.
335 int adjust_pointers();
337 #ifndef SERIALGC
338 // Parallel old
339 void update_header(ParCompactionManager* cm);
340 #endif // SERIALGC
342 // mark-sweep support
343 void follow_body(int begin, int end);
345 // Fast access to barrier set
346 static BarrierSet* bs() { return _bs; }
347 static void set_bs(BarrierSet* bs) { _bs = bs; }
349 // iterators, returns size of object
350 #define OOP_ITERATE_DECL(OopClosureType, nv_suffix) \
351 int oop_iterate(OopClosureType* blk); \
352 int oop_iterate(OopClosureType* blk, MemRegion mr); // Only in mr.
354 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DECL)
355 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DECL)
357 #ifndef SERIALGC
359 #define OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \
360 int oop_iterate_backwards(OopClosureType* blk);
362 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DECL)
363 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DECL)
364 #endif
366 int oop_iterate_no_header(OopClosure* bk);
367 int oop_iterate_no_header(OopClosure* bk, MemRegion mr);
369 // identity hash; returns the identity hash key (computes it if necessary)
370 // NOTE with the introduction of UseBiasedLocking that identity_hash() might reach a
371 // safepoint if called on a biased object. Calling code must be aware of that.
372 intptr_t identity_hash();
373 intptr_t slow_identity_hash();
375 // Alternate hashing code if string table is rehashed
376 unsigned int new_hash(jint seed);
378 // marks are forwarded to stack when object is locked
379 bool has_displaced_mark() const;
380 markOop displaced_mark() const;
381 void set_displaced_mark(markOop m);
383 // for code generation
384 static int mark_offset_in_bytes() { return offset_of(oopDesc, _mark); }
385 static int klass_offset_in_bytes() { return offset_of(oopDesc, _metadata._klass); }
386 static int klass_gap_offset_in_bytes();
387 };
389 #endif // SHARE_VM_OOPS_OOP_HPP