1 /*
2 * Copyright (c) 1997, 2015, 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_OOPS_OOP_INLINE_HPP
26 #define SHARE_VM_OOPS_OOP_INLINE_HPP
27
28 #include "gc/shared/ageTable.hpp"
29 #include "gc/shared/barrierSet.inline.hpp"
30 #include "gc/shared/cardTableModRefBS.hpp"
31 #include "gc/shared/collectedHeap.inline.hpp"
32 #include "gc/shared/genCollectedHeap.hpp"
33 #include "gc/shared/generation.hpp"
34 #include "oops/arrayKlass.hpp"
35 #include "oops/arrayOop.hpp"
36 #include "oops/klass.inline.hpp"
37 #include "oops/markOop.inline.hpp"
38 #include "oops/oop.hpp"
39 #include "runtime/atomic.inline.hpp"
40 #include "runtime/orderAccess.inline.hpp"
41 #include "runtime/os.hpp"
42 #include "utilities/macros.hpp"
43
44 // Implementation of all inlined member functions defined in oop.hpp
45 // We need a separate file to avoid circular references
46
47 inline void oopDesc::release_set_mark(markOop m) {
48 OrderAccess::release_store_ptr(&_mark, m);
49 }
50
51 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
52 return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
53 }
54
55 inline Klass* oopDesc::klass() const {
56 if (UseCompressedClassPointers) {
57 return Klass::decode_klass_not_null(_metadata._compressed_klass);
58 } else {
59 return _metadata._klass;
60 }
61 }
62
63 inline Klass* oopDesc::klass_or_null() const volatile {
64 // can be NULL in CMS
65 if (UseCompressedClassPointers) {
66 return Klass::decode_klass(_metadata._compressed_klass);
67 } else {
68 return _metadata._klass;
69 }
70 }
71
72 inline Klass** oopDesc::klass_addr() {
73 // Only used internally and with CMS and will not work with
74 // UseCompressedOops
75 assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
76 return (Klass**) &_metadata._klass;
77 }
78
79 inline narrowKlass* oopDesc::compressed_klass_addr() {
80 assert(UseCompressedClassPointers, "only called by compressed klass pointers");
81 return &_metadata._compressed_klass;
82 }
83
84 inline void oopDesc::set_klass(Klass* k) {
85 // since klasses are promoted no store check is needed
86 assert(Universe::is_bootstrapping() || k != NULL, "must be a real Klass*");
87 assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass*");
88 if (UseCompressedClassPointers) {
89 *compressed_klass_addr() = Klass::encode_klass_not_null(k);
90 } else {
91 *klass_addr() = k;
92 }
93 }
94
95 inline int oopDesc::klass_gap() const {
96 return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
97 }
98
99 inline void oopDesc::set_klass_gap(int v) {
100 if (UseCompressedClassPointers) {
101 *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
102 }
103 }
104
105 inline void oopDesc::set_klass_to_list_ptr(oop k) {
106 // This is only to be used during GC, for from-space objects, so no
107 // barrier is needed.
108 if (UseCompressedClassPointers) {
109 _metadata._compressed_klass = (narrowKlass)encode_heap_oop(k); // may be null (parnew overflow handling)
110 } else {
111 _metadata._klass = (Klass*)(address)k;
112 }
113 }
114
115 inline oop oopDesc::list_ptr_from_klass() {
116 // This is only to be used during GC, for from-space objects.
117 if (UseCompressedClassPointers) {
118 return decode_heap_oop((narrowOop)_metadata._compressed_klass);
119 } else {
120 // Special case for GC
121 return (oop)(address)_metadata._klass;
122 }
123 }
124
125 inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); }
126
127 inline bool oopDesc::is_a(Klass* k) const { return klass()->is_subtype_of(k); }
128
129 inline bool oopDesc::is_instance() const { return klass()->oop_is_instance(); }
130 inline bool oopDesc::is_instanceClassLoader() const { return klass()->oop_is_instanceClassLoader(); }
131 inline bool oopDesc::is_instanceMirror() const { return klass()->oop_is_instanceMirror(); }
132 inline bool oopDesc::is_instanceRef() const { return klass()->oop_is_instanceRef(); }
133 inline bool oopDesc::is_array() const { return klass()->oop_is_array(); }
134 inline bool oopDesc::is_objArray() const { return klass()->oop_is_objArray(); }
135 inline bool oopDesc::is_typeArray() const { return klass()->oop_is_typeArray(); }
136
137 inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; }
138
139 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
140 inline Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); }
141 inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); }
142 inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); }
143 inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); }
144 inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); }
145 inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); }
146 inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); }
147 inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); }
148 inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
149 inline address* oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
150
151
152 // Functions for getting and setting oops within instance objects.
153 // If the oops are compressed, the type passed to these overloaded functions
154 // is narrowOop. All functions are overloaded so they can be called by
155 // template functions without conditionals (the compiler instantiates via
156 // the right type and inlines the appopriate code).
157
158 inline bool oopDesc::is_null(oop obj) { return obj == NULL; }
159 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
160
161 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
162 // offset from the heap base. Saving the check for null can save instructions
163 // in inner GC loops so these are separated.
164
165 inline bool check_obj_alignment(oop obj) {
166 return cast_from_oop<intptr_t>(obj) % MinObjAlignmentInBytes == 0;
167 }
168
169 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
170 assert(!is_null(v), "oop value can never be zero");
171 assert(check_obj_alignment(v), "Address not aligned");
172 assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
173 address base = Universe::narrow_oop_base();
174 int shift = Universe::narrow_oop_shift();
175 uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
176 assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
177 uint64_t result = pd >> shift;
178 assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
179 assert(decode_heap_oop(result) == v, "reversibility");
180 return (narrowOop)result;
181 }
182
183 inline narrowOop oopDesc::encode_heap_oop(oop v) {
184 return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
185 }
186
187 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
188 assert(!is_null(v), "narrow oop value can never be zero");
189 address base = Universe::narrow_oop_base();
190 int shift = Universe::narrow_oop_shift();
191 oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
192 assert(check_obj_alignment(result), err_msg("address not aligned: " INTPTR_FORMAT, p2i((void*) result)));
193 return result;
194 }
195
196 inline oop oopDesc::decode_heap_oop(narrowOop v) {
197 return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
198 }
199
200 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
201 inline oop oopDesc::decode_heap_oop(oop v) { return v; }
202
203 // Load an oop out of the Java heap as is without decoding.
204 // Called by GC to check for null before decoding.
205 inline oop oopDesc::load_heap_oop(oop* p) { return *p; }
206 inline narrowOop oopDesc::load_heap_oop(narrowOop* p) { return *p; }
207
208 // Load and decode an oop out of the Java heap into a wide oop.
209 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p) { return *p; }
210 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
211 return decode_heap_oop_not_null(*p);
212 }
213
214 // Load and decode an oop out of the heap accepting null
215 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
216 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
217 return decode_heap_oop(*p);
218 }
219
220 // Store already encoded heap oop into the heap.
221 inline void oopDesc::store_heap_oop(oop* p, oop v) { *p = v; }
222 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v) { *p = v; }
223
224 // Encode and store a heap oop.
225 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
226 *p = encode_heap_oop_not_null(v);
227 }
228 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
229
230 // Encode and store a heap oop allowing for null.
231 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
232 *p = encode_heap_oop(v);
233 }
234 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
235
236 // Store heap oop as is for volatile fields.
237 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
238 OrderAccess::release_store_ptr(p, v);
239 }
240 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
241 narrowOop v) {
242 OrderAccess::release_store(p, v);
243 }
244
245 inline void oopDesc::release_encode_store_heap_oop_not_null(
246 volatile narrowOop* p, oop v) {
247 // heap oop is not pointer sized.
248 OrderAccess::release_store(p, encode_heap_oop_not_null(v));
249 }
250
251 inline void oopDesc::release_encode_store_heap_oop_not_null(
252 volatile oop* p, oop v) {
253 OrderAccess::release_store_ptr(p, v);
254 }
255
256 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
257 oop v) {
258 OrderAccess::release_store_ptr(p, v);
259 }
260 inline void oopDesc::release_encode_store_heap_oop(
261 volatile narrowOop* p, oop v) {
262 OrderAccess::release_store(p, encode_heap_oop(v));
263 }
264
265
266 // These functions are only used to exchange oop fields in instances,
267 // not headers.
268 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
269 if (UseCompressedOops) {
270 // encode exchange value from oop to T
271 narrowOop val = encode_heap_oop(exchange_value);
272 narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
273 // decode old from T to oop
274 return decode_heap_oop(old);
275 } else {
276 return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
277 }
278 }
279
280 // In order to put or get a field out of an instance, must first check
281 // if the field has been compressed and uncompress it.
282 inline oop oopDesc::obj_field(int offset) const {
283 oop p = bs()->resolve_oop((oop) this);
284 return UseCompressedOops ?
285 load_decode_heap_oop(p->obj_field_addr<narrowOop>(offset)) :
286 load_decode_heap_oop(p->obj_field_addr<oop>(offset));
287 }
288
289 inline void oopDesc::obj_field_put(int offset, oop value) {
290 oop p = bs()->resolve_and_maybe_copy_oop(this);
291 value = bs()->resolve_oop(value);
292 UseCompressedOops ? oop_store(p->obj_field_addr<narrowOop>(offset), value) :
293 oop_store(p->obj_field_addr<oop>(offset), value);
294 }
295
296 inline Metadata* oopDesc::metadata_field(int offset) const {
297 oop p = bs()->resolve_oop((oop) this);
298 return *p->metadata_field_addr(offset);
299 }
300
301 inline void oopDesc::metadata_field_put(int offset, Metadata* value) {
302 oop p = bs()->resolve_and_maybe_copy_oop(this);
303 *p->metadata_field_addr(offset) = value;
304 }
305
306 inline void oopDesc::obj_field_put_raw(int offset, oop value) {
307 oop p = bs()->resolve_and_maybe_copy_oop(this);
308 value = bs()->resolve_oop(value);
309 UseCompressedOops ?
310 encode_store_heap_oop(p->obj_field_addr<narrowOop>(offset), value) :
311 encode_store_heap_oop(p->obj_field_addr<oop>(offset), value);
312 }
313 inline void oopDesc::obj_field_put_volatile(int offset, oop value) {
314 OrderAccess::release();
315 obj_field_put(offset, value);
316 OrderAccess::fence();
317 }
318
319 inline jbyte oopDesc::byte_field(int offset) const {
320 oop p = bs()->resolve_oop((oop) this);
321 return (jbyte) *p->byte_field_addr(offset);
322 }
323 inline void oopDesc::byte_field_put(int offset, jbyte contents) {
324 oop p = bs()->resolve_and_maybe_copy_oop(this);
325 *p->byte_field_addr(offset) = (jint) contents;
326 }
327
328 inline jboolean oopDesc::bool_field(int offset) const {
329 oop p = bs()->resolve_oop((oop) this);
330 return (jboolean) *p->bool_field_addr(offset);
331 }
332 inline void oopDesc::bool_field_put(int offset, jboolean contents) {
333 oop p = bs()->resolve_and_maybe_copy_oop(this);
334 *p->bool_field_addr(offset) = (jint) contents;
335 }
336
337 inline jchar oopDesc::char_field(int offset) const {
338 oop p = bs()->resolve_oop((oop) this);
339 return (jchar) *p->char_field_addr(offset);
340 }
341 inline void oopDesc::char_field_put(int offset, jchar contents) {
342 oop p = bs()->resolve_and_maybe_copy_oop(this);
343 *p->char_field_addr(offset) = (jint) contents;
344 }
345
346 inline jint oopDesc::int_field(int offset) const {
347 oop p = bs()->resolve_oop((oop) this);
348 return *p->int_field_addr(offset);
349 }
350 inline void oopDesc::int_field_put(int offset, jint contents) {
351 oop p = bs()->resolve_and_maybe_copy_oop(this);
352 *p->int_field_addr(offset) = contents;
353 }
354
355 inline jshort oopDesc::short_field(int offset) const {
356 oop p = bs()->resolve_oop((oop) this);
357 return (jshort) *p->short_field_addr(offset);
358 }
359 inline void oopDesc::short_field_put(int offset, jshort contents) {
360 oop p = bs()->resolve_and_maybe_copy_oop(this);
361 *p->short_field_addr(offset) = (jint) contents;
362 }
363
364 inline jlong oopDesc::long_field(int offset) const {
365 oop p = bs()->resolve_oop((oop) this);
366 return *p->long_field_addr(offset);
367 }
368 inline void oopDesc::long_field_put(int offset, jlong contents) {
369 oop p = bs()->resolve_and_maybe_copy_oop(this);
370 *p->long_field_addr(offset) = contents;
371 }
372
373 inline jfloat oopDesc::float_field(int offset) const {
374 oop p = bs()->resolve_oop((oop) this);
375 return *p->float_field_addr(offset);
376 }
377 inline void oopDesc::float_field_put(int offset, jfloat contents) {
378 oop p = bs()->resolve_and_maybe_copy_oop(this);
379 *p->float_field_addr(offset) = contents;
380 }
381
382 inline jdouble oopDesc::double_field(int offset) const {
383 oop p = bs()->resolve_oop((oop) this);
384 return *p->double_field_addr(offset);
385 }
386 inline void oopDesc::double_field_put(int offset, jdouble contents) {
387 oop p = bs()->resolve_and_maybe_copy_oop(this);
388 *p->double_field_addr(offset) = contents;
389 }
390
391 inline address oopDesc::address_field(int offset) const {
392 oop p = bs()->resolve_oop((oop) this);
393 return *p->address_field_addr(offset);
394 }
395 inline void oopDesc::address_field_put(int offset, address contents) {
396 oop p = bs()->resolve_and_maybe_copy_oop(this);
397 *p->address_field_addr(offset) = contents;
398 }
399
400 inline oop oopDesc::obj_field_acquire(int offset) const {
401 oop p = bs()->resolve_oop((oop) this);
402 return UseCompressedOops ?
403 decode_heap_oop((narrowOop)
404 OrderAccess::load_acquire(p->obj_field_addr<narrowOop>(offset)))
405 : decode_heap_oop((oop)
406 OrderAccess::load_ptr_acquire(p->obj_field_addr<oop>(offset)));
407 }
408 inline void oopDesc::release_obj_field_put(int offset, oop value) {
409 oop p = bs()->resolve_and_maybe_copy_oop(this);
410 value = bs()->resolve_oop(value);
411 UseCompressedOops ?
412 oop_store((volatile narrowOop*)p->obj_field_addr<narrowOop>(offset), value) :
413 oop_store((volatile oop*) p->obj_field_addr<oop>(offset), value);
414 }
415
416 inline jbyte oopDesc::byte_field_acquire(int offset) const {
417 oop p = bs()->resolve_oop((oop) this);
418 return OrderAccess::load_acquire(p->byte_field_addr(offset));
419 }
420 inline void oopDesc::release_byte_field_put(int offset, jbyte contents) {
421 oop p = bs()->resolve_and_maybe_copy_oop(this);
422 OrderAccess::release_store(p->byte_field_addr(offset), contents);
423 }
424
425 inline jboolean oopDesc::bool_field_acquire(int offset) const {
426 oop p = bs()->resolve_oop((oop) this);
427 return OrderAccess::load_acquire(p->bool_field_addr(offset));
428 }
429 inline void oopDesc::release_bool_field_put(int offset, jboolean contents) {
430 oop p = bs()->resolve_and_maybe_copy_oop(this);
431 OrderAccess::release_store(p->bool_field_addr(offset), contents);
432 }
433
434 inline jchar oopDesc::char_field_acquire(int offset) const {
435 oop p = bs()->resolve_oop((oop) this);
436 return OrderAccess::load_acquire(p->char_field_addr(offset));
437 }
438 inline void oopDesc::release_char_field_put(int offset, jchar contents) {
439 oop p = bs()->resolve_and_maybe_copy_oop(this);
440 OrderAccess::release_store(p->char_field_addr(offset), contents);
441 }
442
443 inline jint oopDesc::int_field_acquire(int offset) const {
444 oop p = bs()->resolve_oop((oop) this);
445 return OrderAccess::load_acquire(p->int_field_addr(offset));
446 }
447 inline void oopDesc::release_int_field_put(int offset, jint contents) {
448 oop p = bs()->resolve_and_maybe_copy_oop(this);
449 OrderAccess::release_store(p->int_field_addr(offset), contents);
450 }
451
452 inline jshort oopDesc::short_field_acquire(int offset) const {
453 oop p = bs()->resolve_oop((oop) this);
454 return (jshort)OrderAccess::load_acquire(p->short_field_addr(offset));
455 }
456 inline void oopDesc::release_short_field_put(int offset, jshort contents) {
457 oop p = bs()->resolve_and_maybe_copy_oop(this);
458 OrderAccess::release_store(p->short_field_addr(offset), contents);
459 }
460
461 inline jlong oopDesc::long_field_acquire(int offset) const {
462 oop p = bs()->resolve_oop((oop) this);
463 return OrderAccess::load_acquire(p->long_field_addr(offset));
464 }
465 inline void oopDesc::release_long_field_put(int offset, jlong contents) {
466 oop p = bs()->resolve_and_maybe_copy_oop(this);
467 OrderAccess::release_store(p->long_field_addr(offset), contents);
468 }
469
470 inline jfloat oopDesc::float_field_acquire(int offset) const {
471 oop p = bs()->resolve_oop((oop) this);
472 return OrderAccess::load_acquire(p->float_field_addr(offset));
473 }
474 inline void oopDesc::release_float_field_put(int offset, jfloat contents) {
475 oop p = bs()->resolve_and_maybe_copy_oop(this);
476 OrderAccess::release_store(p->float_field_addr(offset), contents);
477 }
478
479 inline jdouble oopDesc::double_field_acquire(int offset) const {
480 oop p = bs()->resolve_oop((oop) this);
481 return OrderAccess::load_acquire(p->double_field_addr(offset));
482 }
483 inline void oopDesc::release_double_field_put(int offset, jdouble contents) {
484 oop p = bs()->resolve_and_maybe_copy_oop(this);
485 OrderAccess::release_store(p->double_field_addr(offset), contents);
486 }
487
488 inline address oopDesc::address_field_acquire(int offset) const {
489 oop p = bs()->resolve_oop((oop) this);
490 return (address) OrderAccess::load_ptr_acquire(p->address_field_addr(offset));
491 }
492 inline void oopDesc::release_address_field_put(int offset, address contents) {
493 oop p = bs()->resolve_and_maybe_copy_oop(this);
494 OrderAccess::release_store_ptr(p->address_field_addr(offset), contents);
495 }
496
497 inline int oopDesc::size_given_klass(Klass* klass) {
498 int lh = klass->layout_helper();
499 int s;
500
501 // lh is now a value computed at class initialization that may hint
502 // at the size. For instances, this is positive and equal to the
503 // size. For arrays, this is negative and provides log2 of the
504 // array element size. For other oops, it is zero and thus requires
505 // a virtual call.
506 //
507 // We go to all this trouble because the size computation is at the
508 // heart of phase 2 of mark-compaction, and called for every object,
509 // alive or dead. So the speed here is equal in importance to the
510 // speed of allocation.
511
512 if (lh > Klass::_lh_neutral_value) {
513 if (!Klass::layout_helper_needs_slow_path(lh)) {
514 s = lh >> LogHeapWordSize; // deliver size scaled by wordSize
515 } else {
516 s = klass->oop_size(this);
517 }
518 } else if (lh <= Klass::_lh_neutral_value) {
519 // The most common case is instances; fall through if so.
520 if (lh < Klass::_lh_neutral_value) {
521 // Second most common case is arrays. We have to fetch the
522 // length of the array, shift (multiply) it appropriately,
523 // up to wordSize, add the header, and align to object size.
524 size_t size_in_bytes;
525 #ifdef _M_IA64
526 // The Windows Itanium Aug 2002 SDK hoists this load above
527 // the check for s < 0. An oop at the end of the heap will
528 // cause an access violation if this load is performed on a non
529 // array oop. Making the reference volatile prohibits this.
530 // (%%% please explain by what magic the length is actually fetched!)
531 volatile int *array_length;
532 array_length = (volatile int *)( (intptr_t)this +
533 arrayOopDesc::length_offset_in_bytes() );
534 assert(array_length > 0, "Integer arithmetic problem somewhere");
535 // Put into size_t to avoid overflow.
536 size_in_bytes = (size_t) array_length;
537 size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
538 #else
539 size_t array_length = (size_t) ((arrayOop)this)->length();
540 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
541 #endif
542 size_in_bytes += Klass::layout_helper_header_size(lh);
543
544 // This code could be simplified, but by keeping array_header_in_bytes
545 // in units of bytes and doing it this way we can round up just once,
546 // skipping the intermediate round to HeapWordSize. Cast the result
547 // of round_to to size_t to guarantee unsigned division == right shift.
548 s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
549 HeapWordSize);
550
551 // ParNew (used by CMS), UseParallelGC and UseG1GC can change the length field
552 // of an "old copy" of an object array in the young gen so it indicates
553 // the grey portion of an already copied array. This will cause the first
554 // disjunct below to fail if the two comparands are computed across such
555 // a concurrent change.
556 // ParNew also runs with promotion labs (which look like int
557 // filler arrays) which are subject to changing their declared size
558 // when finally retiring a PLAB; this also can cause the first disjunct
559 // to fail for another worker thread that is concurrently walking the block
560 // offset table. Both these invariant failures are benign for their
561 // current uses; we relax the assertion checking to cover these two cases below:
562 // is_objArray() && is_forwarded() // covers first scenario above
563 // || is_typeArray() // covers second scenario above
564 // If and when UseParallelGC uses the same obj array oop stealing/chunking
565 // technique, we will need to suitably modify the assertion.
566 assert((s == klass->oop_size(this)) ||
567 (Universe::heap()->is_gc_active() &&
568 ((is_typeArray() && UseConcMarkSweepGC) ||
569 (is_objArray() && is_forwarded() && (UseConcMarkSweepGC || UseParallelGC || UseG1GC)))),
570 "wrong array object size");
571 } else {
572 // Must be zero, so bite the bullet and take the virtual call.
573 s = klass->oop_size(this);
574 }
575 }
576
577 assert(s % MinObjAlignment == 0, "alignment check");
578 assert(s > 0, "Bad size calculated");
579 return s;
580 }
581
582
583 inline int oopDesc::size() {
584 return size_given_klass(klass());
585 }
586
587 inline void update_barrier_set(void* p, oop v, bool release = false) {
588 assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
589 oopDesc::bs()->write_ref_field(p, v, release);
590 }
591
592 template <class T> inline void update_barrier_set_pre(T* p, oop v) {
593 oopDesc::bs()->write_ref_field_pre(p, v);
594 }
595
596 template <class T> inline void oop_store(T* p, oop v) {
597 if (always_do_update_barrier) {
598 oop_store((volatile T*)p, v);
599 } else {
600 update_barrier_set_pre(p, v);
601 oopDesc::encode_store_heap_oop(p, v);
602 // always_do_update_barrier == false =>
603 // Either we are at a safepoint (in GC) or CMS is not used. In both
604 // cases it's unnecessary to mark the card as dirty with release sematics.
605 update_barrier_set((void*)p, v, false /* release */); // cast away type
606 }
607 }
608
609 template <class T> inline void oop_store(volatile T* p, oop v) {
610 update_barrier_set_pre((T*)p, v); // cast away volatile
611 // Used by release_obj_field_put, so use release_store_ptr.
612 oopDesc::release_encode_store_heap_oop(p, v);
613 // When using CMS we must mark the card corresponding to p as dirty
614 // with release sematics to prevent that CMS sees the dirty card but
615 // not the new value v at p due to reordering of the two
616 // stores. Note that CMS has a concurrent precleaning phase, where
617 // it reads the card table while the Java threads are running.
618 update_barrier_set((void*)p, v, true /* release */); // cast away type
619 }
620
621 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
622 // (without having to remember the function name this calls).
623 inline void oop_store_raw(HeapWord* addr, oop value) {
624 if (UseCompressedOops) {
625 oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
626 } else {
627 oopDesc::encode_store_heap_oop((oop*)addr, value);
628 }
629 }
630
631 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
632 volatile HeapWord *dest,
633 oop compare_value,
634 bool prebarrier) {
635 if (UseCompressedOops) {
636 if (prebarrier) {
637 update_barrier_set_pre((narrowOop*)dest, exchange_value);
638 }
639 // encode exchange and compare value from oop to T
640 narrowOop val = encode_heap_oop(exchange_value);
641 narrowOop cmp = encode_heap_oop(compare_value);
642
643 narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
644 // decode old from T to oop
645 return decode_heap_oop(old);
646 } else {
647 if (prebarrier) {
648 update_barrier_set_pre((oop*)dest, exchange_value);
649 }
650 return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
651 }
652 }
653
654 // Used only for markSweep, scavenging
655 inline bool oopDesc::is_gc_marked() const {
656 return mark()->is_marked();
657 }
658
659 inline bool oopDesc::is_locked() const {
660 return mark()->is_locked();
661 }
662
663 inline bool oopDesc::is_unlocked() const {
664 return mark()->is_unlocked();
665 }
666
667 inline bool oopDesc::has_bias_pattern() const {
668 return mark()->has_bias_pattern();
669 }
670
671
672 // used only for asserts
673 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
674 oop obj = (oop) this;
675 if (!check_obj_alignment(obj)) return false;
676 if (!Universe::heap()->is_in_reserved(obj)) return false;
677 // obj is aligned and accessible in heap
678 if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
679
680 // Header verification: the mark is typically non-NULL. If we're
681 // at a safepoint, it must not be null.
682 // Outside of a safepoint, the header could be changing (for example,
683 // another thread could be inflating a lock on this object).
684 if (ignore_mark_word) {
685 return true;
686 }
687 if (mark() != NULL) {
688 return true;
689 }
690 return !SafepointSynchronize::is_at_safepoint();
691 }
692
693
694 // used only for asserts
695 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
696 return this == NULL ? true : is_oop(ignore_mark_word);
697 }
698
699 #ifndef PRODUCT
700 // used only for asserts
701 inline bool oopDesc::is_unlocked_oop() const {
702 if (!Universe::heap()->is_in_reserved(this)) return false;
703 return mark()->is_unlocked();
704 }
705 #endif // PRODUCT
706
707 inline bool oopDesc::is_scavengable() const {
708 return Universe::heap()->is_scavengable(this);
709 }
710
711 // Used by scavengers
712 inline bool oopDesc::is_forwarded() const {
713 // The extra heap check is needed since the obj might be locked, in which case the
714 // mark would point to a stack location and have the sentinel bit cleared
715 return mark()->is_marked();
716 }
717
718 // Used by scavengers
719 inline void oopDesc::forward_to(oop p) {
720 assert(check_obj_alignment(p),
721 "forwarding to something not aligned");
722 assert(Universe::heap()->is_in_reserved(p),
723 "forwarding to something not in heap");
724 markOop m = markOopDesc::encode_pointer_as_mark(p);
725 assert(m->decode_pointer() == p, "encoding must be reversable");
726 set_mark(m);
727 }
728
729 // Used by parallel scavengers
730 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
731 assert(check_obj_alignment(p),
732 "forwarding to something not aligned");
733 assert(Universe::heap()->is_in_reserved(p),
734 "forwarding to something not in heap");
735 markOop m = markOopDesc::encode_pointer_as_mark(p);
736 assert(m->decode_pointer() == p, "encoding must be reversable");
737 return cas_set_mark(m, compare) == compare;
738 }
739
740 #if INCLUDE_ALL_GCS
741 inline oop oopDesc::forward_to_atomic(oop p) {
742 markOop oldMark = mark();
743 markOop forwardPtrMark = markOopDesc::encode_pointer_as_mark(p);
744 markOop curMark;
745
746 assert(forwardPtrMark->decode_pointer() == p, "encoding must be reversable");
747 assert(sizeof(markOop) == sizeof(intptr_t), "CAS below requires this.");
748
749 while (!oldMark->is_marked()) {
750 curMark = (markOop)Atomic::cmpxchg_ptr(forwardPtrMark, &_mark, oldMark);
751 assert(is_forwarded(), "object should have been forwarded");
752 if (curMark == oldMark) {
753 return NULL;
754 }
755 // If the CAS was unsuccessful then curMark->is_marked()
756 // should return true as another thread has CAS'd in another
757 // forwarding pointer.
758 oldMark = curMark;
759 }
760 return forwardee();
761 }
762 #endif
763
764 // Note that the forwardee is not the same thing as the displaced_mark.
765 // The forwardee is used when copying during scavenge and mark-sweep.
766 // It does need to clear the low two locking- and GC-related bits.
767 inline oop oopDesc::forwardee() const {
768 return (oop) mark()->decode_pointer();
769 }
770
771 inline bool oopDesc::has_displaced_mark() const {
772 return mark()->has_displaced_mark_helper();
773 }
774
775 inline markOop oopDesc::displaced_mark() const {
776 return mark()->displaced_mark_helper();
777 }
778
779 inline void oopDesc::set_displaced_mark(markOop m) {
780 mark()->set_displaced_mark_helper(m);
781 }
782
783 // The following method needs to be MT safe.
784 inline uint oopDesc::age() const {
785 assert(!is_forwarded(), "Attempt to read age from forwarded mark");
786 if (has_displaced_mark()) {
787 return displaced_mark()->age();
788 } else {
789 return mark()->age();
790 }
791 }
792
793 inline void oopDesc::incr_age() {
794 assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
795 if (has_displaced_mark()) {
796 set_displaced_mark(displaced_mark()->incr_age());
797 } else {
798 set_mark(mark()->incr_age());
799 }
800 }
801
802
803 inline intptr_t oopDesc::identity_hash() {
804 // Fast case; if the object is unlocked and the hash value is set, no locking is needed
805 // Note: The mark must be read into local variable to avoid concurrent updates.
806 markOop mrk = mark();
807 if (mrk->is_unlocked() && !mrk->has_no_hash()) {
808 return mrk->hash();
809 } else if (mrk->is_marked()) {
810 return mrk->hash();
811 } else {
812 return slow_identity_hash();
813 }
814 }
815
816 inline int oopDesc::ms_adjust_pointers() {
817 debug_only(int check_size = size());
818 int s = klass()->oop_ms_adjust_pointers(this);
819 assert(s == check_size, "should be the same");
820 return s;
821 }
822
823 #if INCLUDE_ALL_GCS
824 inline void oopDesc::pc_follow_contents(ParCompactionManager* cm) {
825 klass()->oop_pc_follow_contents(this, cm);
826 }
827
828 inline void oopDesc::pc_update_contents() {
829 Klass* k = klass();
830 if (!k->oop_is_typeArray()) {
831 // It might contain oops beyond the header, so take the virtual call.
832 k->oop_pc_update_pointers(this);
833 }
834 // Else skip it. The TypeArrayKlass in the header never needs scavenging.
835 }
836
837 inline void oopDesc::ps_push_contents(PSPromotionManager* pm) {
838 Klass* k = klass();
839 if (!k->oop_is_typeArray()) {
840 // It might contain oops beyond the header, so take the virtual call.
841 k->oop_ps_push_contents(this, pm);
842 }
843 // Else skip it. The TypeArrayKlass in the header never needs scavenging.
844 }
845 #endif
846
847 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
848 \
849 inline void oopDesc::oop_iterate(OopClosureType* blk) { \
850 klass()->oop_oop_iterate##nv_suffix(this, blk); \
851 } \
852 \
853 inline void oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \
854 klass()->oop_oop_iterate_bounded##nv_suffix(this, blk, mr); \
855 }
856
857 #define OOP_ITERATE_SIZE_DEFN(OopClosureType, nv_suffix) \
858 \
859 inline int oopDesc::oop_iterate_size(OopClosureType* blk) { \
860 Klass* k = klass(); \
861 int size = size_given_klass(k); \
862 k->oop_oop_iterate##nv_suffix(this, blk); \
863 return size; \
864 } \
865 \
866 inline int oopDesc::oop_iterate_size(OopClosureType* blk, \
867 MemRegion mr) { \
868 Klass* k = klass(); \
869 int size = size_given_klass(k); \
870 k->oop_oop_iterate_bounded##nv_suffix(this, blk, mr); \
871 return size; \
872 }
873
874 inline int oopDesc::oop_iterate_no_header(OopClosure* blk) {
875 // The NoHeaderExtendedOopClosure wraps the OopClosure and proxies all
876 // the do_oop calls, but turns off all other features in ExtendedOopClosure.
877 NoHeaderExtendedOopClosure cl(blk);
878 return oop_iterate_size(&cl);
879 }
880
881 inline int oopDesc::oop_iterate_no_header(OopClosure* blk, MemRegion mr) {
882 NoHeaderExtendedOopClosure cl(blk);
883 return oop_iterate_size(&cl, mr);
884 }
885
886 #if INCLUDE_ALL_GCS
887 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
888 \
889 inline void oopDesc::oop_iterate_backwards(OopClosureType* blk) { \
890 klass()->oop_oop_iterate_backwards##nv_suffix(this, blk); \
891 }
892 #else
893 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix)
894 #endif
895
896 #define ALL_OOPDESC_OOP_ITERATE(OopClosureType, nv_suffix) \
897 OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
898 OOP_ITERATE_SIZE_DEFN(OopClosureType, nv_suffix) \
899 OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix)
900
901 ALL_OOP_OOP_ITERATE_CLOSURES_1(ALL_OOPDESC_OOP_ITERATE)
902 ALL_OOP_OOP_ITERATE_CLOSURES_2(ALL_OOPDESC_OOP_ITERATE)
903
904 #endif // SHARE_VM_OOPS_OOP_INLINE_HPP