1 /*
2 * Copyright (c) 1997, 2013, 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 */
24
25 #ifndef SHARE_VM_OOPS_OOP_INLINE_HPP
26 #define SHARE_VM_OOPS_OOP_INLINE_HPP
27
28 #include "gc_implementation/shared/ageTable.hpp"
29 #include "gc_implementation/shared/markSweep.inline.hpp"
30 #include "gc_interface/collectedHeap.inline.hpp"
31 #include "memory/barrierSet.inline.hpp"
32 #include "memory/cardTableModRefBS.hpp"
33 #include "memory/genCollectedHeap.hpp"
34 #include "memory/generation.hpp"
35 #include "memory/specialized_oop_closures.hpp"
36 #include "oops/arrayKlass.hpp"
37 #include "oops/arrayOop.hpp"
38 #include "oops/klass.inline.hpp"
39 #include "oops/markOop.inline.hpp"
40 #include "oops/oop.hpp"
41 #include "runtime/atomic.hpp"
42 #include "runtime/os.hpp"
43 #include "utilities/macros.hpp"
44 #ifdef TARGET_ARCH_x86
45 # include "bytes_x86.hpp"
46 #endif
47 #ifdef TARGET_ARCH_sparc
48 # include "bytes_sparc.hpp"
49 #endif
50 #ifdef TARGET_ARCH_zero
51 # include "bytes_zero.hpp"
52 #endif
53 #ifdef TARGET_ARCH_arm
54 # include "bytes_arm.hpp"
55 #endif
56 #ifdef TARGET_ARCH_ppc
57 # include "bytes_ppc.hpp"
58 #endif
59
60 // Implementation of all inlined member functions defined in oop.hpp
61 // We need a separate file to avoid circular references
62
63 inline void oopDesc::release_set_mark(markOop m) {
64 OrderAccess::release_store_ptr(&_mark, m);
65 }
66
67 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
68 return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
69 }
70
71 inline Klass* oopDesc::klass() const {
72 if (UseCompressedClassPointers) {
73 return Klass::decode_klass_not_null(_metadata._compressed_klass);
74 } else {
75 return _metadata._klass;
76 }
77 }
78
79 inline Klass* oopDesc::klass_or_null() const volatile {
80 // can be NULL in CMS
81 if (UseCompressedClassPointers) {
82 return Klass::decode_klass(_metadata._compressed_klass);
83 } else {
84 return _metadata._klass;
85 }
86 }
87
88 inline int oopDesc::klass_gap_offset_in_bytes() {
89 assert(UseCompressedClassPointers, "only applicable to compressed klass pointers");
90 return oopDesc::klass_offset_in_bytes() + sizeof(narrowKlass);
91 }
92
93 inline Klass** oopDesc::klass_addr() {
94 // Only used internally and with CMS and will not work with
95 // UseCompressedOops
96 assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
97 return (Klass**) &_metadata._klass;
98 }
99
100 inline narrowKlass* oopDesc::compressed_klass_addr() {
101 assert(UseCompressedClassPointers, "only called by compressed klass pointers");
102 return &_metadata._compressed_klass;
103 }
104
105 inline void oopDesc::set_klass(Klass* k) {
106 // since klasses are promoted no store check is needed
107 assert(Universe::is_bootstrapping() || k != NULL, "must be a real Klass*");
108 assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass*");
109 if (UseCompressedClassPointers) {
110 *compressed_klass_addr() = Klass::encode_klass_not_null(k);
111 } else {
112 *klass_addr() = k;
113 }
114 }
115
116 inline int oopDesc::klass_gap() const {
117 return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
118 }
119
120 inline void oopDesc::set_klass_gap(int v) {
121 if (UseCompressedClassPointers) {
122 *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
123 }
124 }
125
126 inline void oopDesc::set_klass_to_list_ptr(oop k) {
127 // This is only to be used during GC, for from-space objects, so no
128 // barrier is needed.
129 if (UseCompressedClassPointers) {
130 _metadata._compressed_klass = (narrowKlass)encode_heap_oop(k); // may be null (parnew overflow handling)
131 } else {
132 _metadata._klass = (Klass*)(address)k;
133 }
134 }
135
136 inline oop oopDesc::list_ptr_from_klass() {
137 // This is only to be used during GC, for from-space objects.
138 if (UseCompressedClassPointers) {
139 return decode_heap_oop((narrowOop)_metadata._compressed_klass);
140 } else {
141 // Special case for GC
142 return (oop)(address)_metadata._klass;
143 }
144 }
145
146 inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); }
147
148 inline bool oopDesc::is_a(Klass* k) const { return klass()->is_subtype_of(k); }
149
150 inline bool oopDesc::is_instance() const { return klass()->oop_is_instance(); }
151 inline bool oopDesc::is_instanceClassLoader() const { return klass()->oop_is_instanceClassLoader(); }
152 inline bool oopDesc::is_instanceMirror() const { return klass()->oop_is_instanceMirror(); }
153 inline bool oopDesc::is_instanceRef() const { return klass()->oop_is_instanceRef(); }
154 inline bool oopDesc::is_array() const { return klass()->oop_is_array(); }
155 inline bool oopDesc::is_objArray() const { return klass()->oop_is_objArray(); }
156 inline bool oopDesc::is_typeArray() const { return klass()->oop_is_typeArray(); }
157
158 inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; }
159
160 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
161 inline Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); }
162 inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); }
163 inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); }
164 inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); }
165 inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); }
166 inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); }
167 inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); }
168 inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); }
169 inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
170 inline address* oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
171
172
173 // Functions for getting and setting oops within instance objects.
174 // If the oops are compressed, the type passed to these overloaded functions
175 // is narrowOop. All functions are overloaded so they can be called by
176 // template functions without conditionals (the compiler instantiates via
177 // the right type and inlines the appopriate code).
178
179 inline bool oopDesc::is_null(oop obj) { return obj == NULL; }
180 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
181
182 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
183 // offset from the heap base. Saving the check for null can save instructions
184 // in inner GC loops so these are separated.
185
186 inline bool check_obj_alignment(oop obj) {
187 return cast_from_oop<intptr_t>(obj) % MinObjAlignmentInBytes == 0;
188 }
189
190 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
191 assert(!is_null(v), "oop value can never be zero");
192 assert(check_obj_alignment(v), "Address not aligned");
193 assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
194 address base = Universe::narrow_oop_base();
195 int shift = Universe::narrow_oop_shift();
196 uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
197 assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
198 uint64_t result = pd >> shift;
199 assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
200 assert(decode_heap_oop(result) == v, "reversibility");
201 return (narrowOop)result;
202 }
203
204 inline narrowOop oopDesc::encode_heap_oop(oop v) {
205 return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
206 }
207
208 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
209 assert(!is_null(v), "narrow oop value can never be zero");
210 address base = Universe::narrow_oop_base();
211 int shift = Universe::narrow_oop_shift();
212 oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
213 assert(check_obj_alignment(result), err_msg("address not aligned: " PTR_FORMAT, (void*) result));
214 return result;
215 }
216
217 inline oop oopDesc::decode_heap_oop(narrowOop v) {
218 return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
219 }
220
221 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
222 inline oop oopDesc::decode_heap_oop(oop v) { return v; }
223
224 // Load an oop out of the Java heap as is without decoding.
225 // Called by GC to check for null before decoding.
226 inline oop oopDesc::load_heap_oop(oop* p) { return *p; }
227 inline narrowOop oopDesc::load_heap_oop(narrowOop* p) { return *p; }
228
229 // Load and decode an oop out of the Java heap into a wide oop.
230 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p) { return *p; }
231 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
232 return decode_heap_oop_not_null(*p);
233 }
234
235 // Load and decode an oop out of the heap accepting null
236 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
237 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
238 return decode_heap_oop(*p);
239 }
240
241 // Store already encoded heap oop into the heap.
242 inline void oopDesc::store_heap_oop(oop* p, oop v) { *p = v; }
243 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v) { *p = v; }
244
245 // Encode and store a heap oop.
246 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
247 *p = encode_heap_oop_not_null(v);
248 }
249 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
250
251 // Encode and store a heap oop allowing for null.
252 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
253 *p = encode_heap_oop(v);
254 }
255 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
256
257 // Store heap oop as is for volatile fields.
258 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
259 OrderAccess::release_store_ptr(p, v);
260 }
261 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
262 narrowOop v) {
263 OrderAccess::release_store(p, v);
264 }
265
266 inline void oopDesc::release_encode_store_heap_oop_not_null(
267 volatile narrowOop* p, oop v) {
268 // heap oop is not pointer sized.
269 OrderAccess::release_store(p, encode_heap_oop_not_null(v));
270 }
271
272 inline void oopDesc::release_encode_store_heap_oop_not_null(
273 volatile oop* p, oop v) {
274 OrderAccess::release_store_ptr(p, v);
275 }
276
277 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
278 oop v) {
279 OrderAccess::release_store_ptr(p, v);
280 }
281 inline void oopDesc::release_encode_store_heap_oop(
282 volatile narrowOop* p, oop v) {
283 OrderAccess::release_store(p, encode_heap_oop(v));
284 }
285
286
287 // These functions are only used to exchange oop fields in instances,
288 // not headers.
289 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
290 if (UseCompressedOops) {
291 // encode exchange value from oop to T
292 narrowOop val = encode_heap_oop(exchange_value);
293 narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
294 // decode old from T to oop
295 return decode_heap_oop(old);
296 } else {
297 return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
298 }
299 }
300
301 // In order to put or get a field out of an instance, must first check
302 // if the field has been compressed and uncompress it.
303 inline oop oopDesc::obj_field(int offset) const {
304 return UseCompressedOops ?
305 load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :
306 load_decode_heap_oop(obj_field_addr<oop>(offset));
307 }
308 inline volatile oop oopDesc::obj_field_volatile(int offset) const {
309 volatile oop value = obj_field(offset);
310 OrderAccess::acquire();
311 return value;
312 }
313 inline void oopDesc::obj_field_put(int offset, oop value) {
314 UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
315 oop_store(obj_field_addr<oop>(offset), value);
316 }
317
318 inline Metadata* oopDesc::metadata_field(int offset) const {
319 return *metadata_field_addr(offset);
320 }
321
322 inline void oopDesc::metadata_field_put(int offset, Metadata* value) {
323 *metadata_field_addr(offset) = value;
324 }
325
326 inline void oopDesc::obj_field_put_raw(int offset, oop value) {
327 UseCompressedOops ?
328 encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
329 encode_store_heap_oop(obj_field_addr<oop>(offset), value);
330 }
331 inline void oopDesc::obj_field_put_volatile(int offset, oop value) {
332 OrderAccess::release();
333 obj_field_put(offset, value);
334 OrderAccess::fence();
335 }
336
337 inline jbyte oopDesc::byte_field(int offset) const { return (jbyte) *byte_field_addr(offset); }
338 inline void oopDesc::byte_field_put(int offset, jbyte contents) { *byte_field_addr(offset) = (jint) contents; }
339
340 inline jboolean oopDesc::bool_field(int offset) const { return (jboolean) *bool_field_addr(offset); }
341 inline void oopDesc::bool_field_put(int offset, jboolean contents) { *bool_field_addr(offset) = (jint) contents; }
342
343 inline jchar oopDesc::char_field(int offset) const { return (jchar) *char_field_addr(offset); }
344 inline void oopDesc::char_field_put(int offset, jchar contents) { *char_field_addr(offset) = (jint) contents; }
345
346 inline jint oopDesc::int_field(int offset) const { return *int_field_addr(offset); }
347 inline void oopDesc::int_field_put(int offset, jint contents) { *int_field_addr(offset) = contents; }
348
349 inline jshort oopDesc::short_field(int offset) const { return (jshort) *short_field_addr(offset); }
350 inline void oopDesc::short_field_put(int offset, jshort contents) { *short_field_addr(offset) = (jint) contents;}
351
352 inline jlong oopDesc::long_field(int offset) const { return *long_field_addr(offset); }
353 inline void oopDesc::long_field_put(int offset, jlong contents) { *long_field_addr(offset) = contents; }
354
355 inline jfloat oopDesc::float_field(int offset) const { return *float_field_addr(offset); }
356 inline void oopDesc::float_field_put(int offset, jfloat contents) { *float_field_addr(offset) = contents; }
357
358 inline jdouble oopDesc::double_field(int offset) const { return *double_field_addr(offset); }
359 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
360
361 inline address oopDesc::address_field(int offset) const { return *address_field_addr(offset); }
362 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
363
364 inline oop oopDesc::obj_field_acquire(int offset) const {
365 return UseCompressedOops ?
366 decode_heap_oop((narrowOop)
367 OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
368 : decode_heap_oop((oop)
369 OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
370 }
371 inline void oopDesc::release_obj_field_put(int offset, oop value) {
372 UseCompressedOops ?
373 oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
374 oop_store((volatile oop*) obj_field_addr<oop>(offset), value);
375 }
376
377 inline jbyte oopDesc::byte_field_acquire(int offset) const { return OrderAccess::load_acquire(byte_field_addr(offset)); }
378 inline void oopDesc::release_byte_field_put(int offset, jbyte contents) { OrderAccess::release_store(byte_field_addr(offset), contents); }
379
380 inline jboolean oopDesc::bool_field_acquire(int offset) const { return OrderAccess::load_acquire(bool_field_addr(offset)); }
381 inline void oopDesc::release_bool_field_put(int offset, jboolean contents) { OrderAccess::release_store(bool_field_addr(offset), contents); }
382
383 inline jchar oopDesc::char_field_acquire(int offset) const { return OrderAccess::load_acquire(char_field_addr(offset)); }
384 inline void oopDesc::release_char_field_put(int offset, jchar contents) { OrderAccess::release_store(char_field_addr(offset), contents); }
385
386 inline jint oopDesc::int_field_acquire(int offset) const { return OrderAccess::load_acquire(int_field_addr(offset)); }
387 inline void oopDesc::release_int_field_put(int offset, jint contents) { OrderAccess::release_store(int_field_addr(offset), contents); }
388
389 inline jshort oopDesc::short_field_acquire(int offset) const { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
390 inline void oopDesc::release_short_field_put(int offset, jshort contents) { OrderAccess::release_store(short_field_addr(offset), contents); }
391
392 inline jlong oopDesc::long_field_acquire(int offset) const { return OrderAccess::load_acquire(long_field_addr(offset)); }
393 inline void oopDesc::release_long_field_put(int offset, jlong contents) { OrderAccess::release_store(long_field_addr(offset), contents); }
394
395 inline jfloat oopDesc::float_field_acquire(int offset) const { return OrderAccess::load_acquire(float_field_addr(offset)); }
396 inline void oopDesc::release_float_field_put(int offset, jfloat contents) { OrderAccess::release_store(float_field_addr(offset), contents); }
397
398 inline jdouble oopDesc::double_field_acquire(int offset) const { return OrderAccess::load_acquire(double_field_addr(offset)); }
399 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
400
401 inline address oopDesc::address_field_acquire(int offset) const { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); }
402 inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); }
403
404 inline int oopDesc::size_given_klass(Klass* klass) {
405 int lh = klass->layout_helper();
406 int s;
407
408 // lh is now a value computed at class initialization that may hint
409 // at the size. For instances, this is positive and equal to the
410 // size. For arrays, this is negative and provides log2 of the
411 // array element size. For other oops, it is zero and thus requires
412 // a virtual call.
413 //
414 // We go to all this trouble because the size computation is at the
415 // heart of phase 2 of mark-compaction, and called for every object,
416 // alive or dead. So the speed here is equal in importance to the
417 // speed of allocation.
418
419 if (lh > Klass::_lh_neutral_value) {
420 if (!Klass::layout_helper_needs_slow_path(lh)) {
421 s = lh >> LogHeapWordSize; // deliver size scaled by wordSize
422 } else {
423 s = klass->oop_size(this);
424 }
425 } else if (lh <= Klass::_lh_neutral_value) {
426 // The most common case is instances; fall through if so.
427 if (lh < Klass::_lh_neutral_value) {
428 // Second most common case is arrays. We have to fetch the
429 // length of the array, shift (multiply) it appropriately,
430 // up to wordSize, add the header, and align to object size.
431 size_t size_in_bytes;
432 #ifdef _M_IA64
433 // The Windows Itanium Aug 2002 SDK hoists this load above
434 // the check for s < 0. An oop at the end of the heap will
435 // cause an access violation if this load is performed on a non
436 // array oop. Making the reference volatile prohibits this.
437 // (%%% please explain by what magic the length is actually fetched!)
438 volatile int *array_length;
439 array_length = (volatile int *)( (intptr_t)this +
440 arrayOopDesc::length_offset_in_bytes() );
441 assert(array_length > 0, "Integer arithmetic problem somewhere");
442 // Put into size_t to avoid overflow.
443 size_in_bytes = (size_t) array_length;
444 size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
445 #else
446 size_t array_length = (size_t) ((arrayOop)this)->length();
447 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
448 #endif
449 size_in_bytes += Klass::layout_helper_header_size(lh);
450
451 // This code could be simplified, but by keeping array_header_in_bytes
452 // in units of bytes and doing it this way we can round up just once,
453 // skipping the intermediate round to HeapWordSize. Cast the result
454 // of round_to to size_t to guarantee unsigned division == right shift.
455 s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
456 HeapWordSize);
457
458 // UseParNewGC, UseParallelGC and UseG1GC can change the length field
459 // of an "old copy" of an object array in the young gen so it indicates
460 // the grey portion of an already copied array. This will cause the first
461 // disjunct below to fail if the two comparands are computed across such
462 // a concurrent change.
463 // UseParNewGC also runs with promotion labs (which look like int
464 // filler arrays) which are subject to changing their declared size
465 // when finally retiring a PLAB; this also can cause the first disjunct
466 // to fail for another worker thread that is concurrently walking the block
467 // offset table. Both these invariant failures are benign for their
468 // current uses; we relax the assertion checking to cover these two cases below:
469 // is_objArray() && is_forwarded() // covers first scenario above
470 // || is_typeArray() // covers second scenario above
471 // If and when UseParallelGC uses the same obj array oop stealing/chunking
472 // technique, we will need to suitably modify the assertion.
473 assert((s == klass->oop_size(this)) ||
474 (Universe::heap()->is_gc_active() &&
475 ((is_typeArray() && UseParNewGC) ||
476 (is_objArray() && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))),
477 "wrong array object size");
478 } else {
479 // Must be zero, so bite the bullet and take the virtual call.
480 s = klass->oop_size(this);
481 }
482 }
483
484 assert(s % MinObjAlignment == 0, "alignment check");
485 assert(s > 0, "Bad size calculated");
486 return s;
487 }
488
489
490 inline int oopDesc::size() {
491 return size_given_klass(klass());
492 }
493
494 inline void update_barrier_set(void* p, oop v) {
495 assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
496 oopDesc::bs()->write_ref_field(p, v);
497 }
498
499 template <class T> inline void update_barrier_set_pre(T* p, oop v) {
500 oopDesc::bs()->write_ref_field_pre(p, v);
501 }
502
503 template <class T> inline void oop_store(T* p, oop v) {
504 if (always_do_update_barrier) {
505 oop_store((volatile T*)p, v);
506 } else {
507 update_barrier_set_pre(p, v);
508 oopDesc::encode_store_heap_oop(p, v);
509 update_barrier_set((void*)p, v); // cast away type
510 }
511 }
512
513 template <class T> inline void oop_store(volatile T* p, oop v) {
514 update_barrier_set_pre((T*)p, v); // cast away volatile
515 // Used by release_obj_field_put, so use release_store_ptr.
516 oopDesc::release_encode_store_heap_oop(p, v);
517 update_barrier_set((void*)p, v); // cast away type
518 }
519
520 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
521 // (without having to remember the function name this calls).
522 inline void oop_store_raw(HeapWord* addr, oop value) {
523 if (UseCompressedOops) {
524 oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
525 } else {
526 oopDesc::encode_store_heap_oop((oop*)addr, value);
527 }
528 }
529
530 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
531 volatile HeapWord *dest,
532 oop compare_value,
533 bool prebarrier) {
534 if (UseCompressedOops) {
535 if (prebarrier) {
536 update_barrier_set_pre((narrowOop*)dest, exchange_value);
537 }
538 // encode exchange and compare value from oop to T
539 narrowOop val = encode_heap_oop(exchange_value);
540 narrowOop cmp = encode_heap_oop(compare_value);
541
542 narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
543 // decode old from T to oop
544 return decode_heap_oop(old);
545 } else {
546 if (prebarrier) {
547 update_barrier_set_pre((oop*)dest, exchange_value);
548 }
549 return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
550 }
551 }
552
553 // Used only for markSweep, scavenging
554 inline bool oopDesc::is_gc_marked() const {
555 return mark()->is_marked();
556 }
557
558 inline bool oopDesc::is_locked() const {
559 return mark()->is_locked();
560 }
561
562 inline bool oopDesc::is_unlocked() const {
563 return mark()->is_unlocked();
564 }
565
566 inline bool oopDesc::has_bias_pattern() const {
567 return mark()->has_bias_pattern();
568 }
569
570
571 // used only for asserts
572 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
573 oop obj = (oop) this;
574 if (!check_obj_alignment(obj)) return false;
575 if (!Universe::heap()->is_in_reserved(obj)) return false;
576 // obj is aligned and accessible in heap
577 if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
578
579 // Header verification: the mark is typically non-NULL. If we're
580 // at a safepoint, it must not be null.
581 // Outside of a safepoint, the header could be changing (for example,
582 // another thread could be inflating a lock on this object).
583 if (ignore_mark_word) {
584 return true;
585 }
586 if (mark() != NULL) {
587 return true;
588 }
589 return !SafepointSynchronize::is_at_safepoint();
590 }
591
592
593 // used only for asserts
594 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
595 return this == NULL ? true : is_oop(ignore_mark_word);
596 }
597
598 #ifndef PRODUCT
599 // used only for asserts
600 inline bool oopDesc::is_unlocked_oop() const {
601 if (!Universe::heap()->is_in_reserved(this)) return false;
602 return mark()->is_unlocked();
603 }
604 #endif // PRODUCT
605
606 inline void oopDesc::follow_contents(void) {
607 assert (is_gc_marked(), "should be marked");
608 klass()->oop_follow_contents(this);
609 }
610
611 // Used by scavengers
612
613 inline bool oopDesc::is_forwarded() const {
614 // The extra heap check is needed since the obj might be locked, in which case the
615 // mark would point to a stack location and have the sentinel bit cleared
616 return mark()->is_marked();
617 }
618
619 // Used by scavengers
620 inline void oopDesc::forward_to(oop p) {
621 assert(check_obj_alignment(p),
622 "forwarding to something not aligned");
623 assert(Universe::heap()->is_in_reserved(p),
624 "forwarding to something not in heap");
625 markOop m = markOopDesc::encode_pointer_as_mark(p);
626 assert(m->decode_pointer() == p, "encoding must be reversable");
627 set_mark(m);
628 }
629
630 // Used by parallel scavengers
631 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
632 assert(check_obj_alignment(p),
633 "forwarding to something not aligned");
634 assert(Universe::heap()->is_in_reserved(p),
635 "forwarding to something not in heap");
636 markOop m = markOopDesc::encode_pointer_as_mark(p);
637 assert(m->decode_pointer() == p, "encoding must be reversable");
638 return cas_set_mark(m, compare) == compare;
639 }
640
641 // Note that the forwardee is not the same thing as the displaced_mark.
642 // The forwardee is used when copying during scavenge and mark-sweep.
643 // It does need to clear the low two locking- and GC-related bits.
644 inline oop oopDesc::forwardee() const {
645 return (oop) mark()->decode_pointer();
646 }
647
648 inline bool oopDesc::has_displaced_mark() const {
649 return mark()->has_displaced_mark_helper();
650 }
651
652 inline markOop oopDesc::displaced_mark() const {
653 return mark()->displaced_mark_helper();
654 }
655
656 inline void oopDesc::set_displaced_mark(markOop m) {
657 mark()->set_displaced_mark_helper(m);
658 }
659
660 // The following method needs to be MT safe.
661 inline uint oopDesc::age() const {
662 assert(!is_forwarded(), "Attempt to read age from forwarded mark");
663 if (has_displaced_mark()) {
664 return displaced_mark()->age();
665 } else {
666 return mark()->age();
667 }
668 }
669
670 inline void oopDesc::incr_age() {
671 assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
672 if (has_displaced_mark()) {
673 set_displaced_mark(displaced_mark()->incr_age());
674 } else {
675 set_mark(mark()->incr_age());
676 }
677 }
678
679
680 inline intptr_t oopDesc::identity_hash() {
681 // Fast case; if the object is unlocked and the hash value is set, no locking is needed
682 // Note: The mark must be read into local variable to avoid concurrent updates.
683 markOop mrk = mark();
684 if (mrk->is_unlocked() && !mrk->has_no_hash()) {
685 return mrk->hash();
686 } else if (mrk->is_marked()) {
687 return mrk->hash();
688 } else {
689 return slow_identity_hash();
690 }
691 }
692
693 inline int oopDesc::adjust_pointers() {
694 debug_only(int check_size = size());
695 int s = klass()->oop_adjust_pointers(this);
696 assert(s == check_size, "should be the same");
697 return s;
698 }
699
700 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
701 \
702 inline int oopDesc::oop_iterate(OopClosureType* blk) { \
703 SpecializationStats::record_call(); \
704 return klass()->oop_oop_iterate##nv_suffix(this, blk); \
705 } \
706 \
707 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \
708 SpecializationStats::record_call(); \
709 return klass()->oop_oop_iterate##nv_suffix##_m(this, blk, mr); \
710 }
711
712
713 inline int oopDesc::oop_iterate_no_header(OopClosure* blk) {
714 // The NoHeaderExtendedOopClosure wraps the OopClosure and proxies all
715 // the do_oop calls, but turns off all other features in ExtendedOopClosure.
716 NoHeaderExtendedOopClosure cl(blk);
717 return oop_iterate(&cl);
718 }
719
720 inline int oopDesc::oop_iterate_no_header(OopClosure* blk, MemRegion mr) {
721 NoHeaderExtendedOopClosure cl(blk);
722 return oop_iterate(&cl, mr);
723 }
724
725 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
726 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN)
727
728 #if INCLUDE_ALL_GCS
729 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
730 \
731 inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) { \
732 SpecializationStats::record_call(); \
733 return klass()->oop_oop_iterate_backwards##nv_suffix(this, blk); \
734 }
735
736 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN)
737 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN)
738 #endif // INCLUDE_ALL_GCS
739
740 #endif // SHARE_VM_OOPS_OOP_INLINE_HPP