1 /*
2 * Copyright (c) 1997, 2016, 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_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.inline.hpp"
42 #include "runtime/orderAccess.inline.hpp"
43 #include "runtime/os.hpp"
44 #include "utilities/macros.hpp"
45 #ifdef TARGET_ARCH_x86
46 # include "bytes_x86.hpp"
47 #endif
48 #ifdef TARGET_ARCH_aarch64
49 # include "bytes_aarch64.hpp"
50 #endif
51 #ifdef TARGET_ARCH_sparc
52 # include "bytes_sparc.hpp"
53 #endif
54 #ifdef TARGET_ARCH_zero
55 # include "bytes_zero.hpp"
56 #endif
57 #ifdef TARGET_ARCH_arm
58 # include "bytes_arm.hpp"
59 #endif
60 #ifdef TARGET_ARCH_ppc
61 # include "bytes_ppc.hpp"
62 #endif
63
64 #if INCLUDE_ALL_GCS
65 #include "gc_implementation/shenandoah/shenandoahBarrierSet.hpp"
66 #endif
67
68 // Implementation of all inlined member functions defined in oop.hpp
69 // We need a separate file to avoid circular references
70
71 inline void oopDesc::release_set_mark(markOop m) {
72 OrderAccess::release_store_ptr(&_mark, m);
73 }
74
75 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
76 return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
77 }
78
79 inline Klass* oopDesc::klass() const {
80 if (UseCompressedClassPointers) {
81 return Klass::decode_klass_not_null(_metadata._compressed_klass);
82 } else {
83 return _metadata._klass;
84 }
85 }
86
87 inline Klass* oopDesc::klass_or_null() const volatile {
88 if (UseCompressedClassPointers) {
89 return Klass::decode_klass(_metadata._compressed_klass);
90 } else {
91 return _metadata._klass;
92 }
93 }
94
95 inline Klass* oopDesc::klass_or_null_acquire() const volatile {
96 if (UseCompressedClassPointers) {
97 // Workaround for non-const load_acquire parameter.
98 const volatile narrowKlass* addr = &_metadata._compressed_klass;
99 volatile narrowKlass* xaddr = const_cast<volatile narrowKlass*>(addr);
100 return Klass::decode_klass(OrderAccess::load_acquire(xaddr));
101 } else {
102 return (Klass*)OrderAccess::load_ptr_acquire(&_metadata._klass);
103 }
104 }
105
106 inline int oopDesc::klass_gap_offset_in_bytes() {
107 assert(UseCompressedClassPointers, "only applicable to compressed klass pointers");
108 return oopDesc::klass_offset_in_bytes() + sizeof(narrowKlass);
109 }
110
111 inline Klass** oopDesc::klass_addr() {
112 // Only used internally and with CMS and will not work with
113 // UseCompressedOops
114 assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
115 return (Klass**) &_metadata._klass;
116 }
117
118 inline narrowKlass* oopDesc::compressed_klass_addr() {
119 assert(UseCompressedClassPointers, "only called by compressed klass pointers");
120 return &_metadata._compressed_klass;
121 }
122
123 #define CHECK_SET_KLASS(k) \
124 do { \
125 assert(Universe::is_bootstrapping() || k != NULL, "NULL Klass"); \
126 assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass"); \
127 } while (0)
128
129 inline void oopDesc::set_klass(Klass* k) {
130 CHECK_SET_KLASS(k);
131 if (UseCompressedClassPointers) {
132 *compressed_klass_addr() = Klass::encode_klass_not_null(k);
133 } else {
134 *klass_addr() = k;
135 }
136 }
137
138 inline void oopDesc::release_set_klass(Klass* k) {
139 CHECK_SET_KLASS(k);
140 if (UseCompressedClassPointers) {
141 OrderAccess::release_store(compressed_klass_addr(),
142 Klass::encode_klass_not_null(k));
143 } else {
144 OrderAccess::release_store_ptr(klass_addr(), k);
145 }
146 }
147
148 #undef CHECK_SET_KLASS
149
150 inline int oopDesc::klass_gap() const {
151 return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
152 }
153
154 inline void oopDesc::set_klass_gap(int v) {
155 if (UseCompressedClassPointers) {
156 *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
157 }
158 }
159
160 inline void oopDesc::set_klass_to_list_ptr(oop k) {
161 // This is only to be used during GC, for from-space objects, so no
162 // barrier is needed.
163 if (UseCompressedClassPointers) {
164 _metadata._compressed_klass = (narrowKlass)encode_heap_oop(k); // may be null (parnew overflow handling)
165 } else {
166 _metadata._klass = (Klass*)(address)k;
167 }
168 }
169
170 inline oop oopDesc::list_ptr_from_klass() {
171 // This is only to be used during GC, for from-space objects.
172 if (UseCompressedClassPointers) {
173 return decode_heap_oop((narrowOop)_metadata._compressed_klass);
174 } else {
175 // Special case for GC
176 return (oop)(address)_metadata._klass;
177 }
178 }
179
180 inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); }
181
182 inline bool oopDesc::is_a(Klass* k) const { return klass()->is_subtype_of(k); }
183
184 inline bool oopDesc::is_instance() const { return klass()->oop_is_instance(); }
185 inline bool oopDesc::is_instanceClassLoader() const { return klass()->oop_is_instanceClassLoader(); }
186 inline bool oopDesc::is_instanceMirror() const { return klass()->oop_is_instanceMirror(); }
187 inline bool oopDesc::is_instanceRef() const { return klass()->oop_is_instanceRef(); }
188 inline bool oopDesc::is_array() const { return klass()->oop_is_array(); }
189 inline bool oopDesc::is_objArray() const { return klass()->oop_is_objArray(); }
190 inline bool oopDesc::is_typeArray() const { return klass()->oop_is_typeArray(); }
191
192 inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; }
193
194 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
195 inline Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); }
196 inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); }
197 inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); }
198 inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); }
199 inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); }
200 inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); }
201 inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); }
202 inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); }
203 inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
204 inline address* oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
205
206
207 // Functions for getting and setting oops within instance objects.
208 // If the oops are compressed, the type passed to these overloaded functions
209 // is narrowOop. All functions are overloaded so they can be called by
210 // template functions without conditionals (the compiler instantiates via
211 // the right type and inlines the appopriate code).
212
213 inline bool oopDesc::is_null(oop obj) { return obj == NULL; }
214 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
215
216 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
217 // offset from the heap base. Saving the check for null can save instructions
218 // in inner GC loops so these are separated.
219
220 inline bool check_obj_alignment(oop obj) {
221 return cast_from_oop<intptr_t>(obj) % MinObjAlignmentInBytes == 0;
222 }
223
224 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
225 assert(!is_null(v), "oop value can never be zero");
226 assert(check_obj_alignment(v), "Address not aligned");
227 assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
228 address base = Universe::narrow_oop_base();
229 int shift = Universe::narrow_oop_shift();
230 uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
231 assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
232 uint64_t result = pd >> shift;
233 assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
234 assert(decode_heap_oop(result) == v, "reversibility");
235 return (narrowOop)result;
236 }
237
238 inline narrowOop oopDesc::encode_heap_oop(oop v) {
239 return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
240 }
241
242 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
243 assert(!is_null(v), "narrow oop value can never be zero");
244 address base = Universe::narrow_oop_base();
245 int shift = Universe::narrow_oop_shift();
246 oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
247 assert(check_obj_alignment(result), err_msg("address not aligned: " INTPTR_FORMAT, p2i((void*) result)));
248 return result;
249 }
250
251 inline oop oopDesc::decode_heap_oop(narrowOop v) {
252 return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
253 }
254
255 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
256 inline oop oopDesc::decode_heap_oop(oop v) { return v; }
257
258 // Load an oop out of the Java heap as is without decoding.
259 // Called by GC to check for null before decoding.
260 inline oop oopDesc::load_heap_oop(oop* p) { return *p; }
261 inline narrowOop oopDesc::load_heap_oop(narrowOop* p) { return *p; }
262
263 // Load and decode an oop out of the Java heap into a wide oop.
264 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p) { return *p; }
265 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
266 return decode_heap_oop_not_null(*p);
267 }
268
269 // Load and decode an oop out of the heap accepting null
270 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
271 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
272 return decode_heap_oop(*p);
273 }
274
275 // Store already encoded heap oop into the heap.
276 inline void oopDesc::store_heap_oop(oop* p, oop v) { *p = v; }
277 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v) { *p = v; }
278
279 // Encode and store a heap oop.
280 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
281 *p = encode_heap_oop_not_null(v);
282 }
283 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
284
285 // Encode and store a heap oop allowing for null.
286 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
287 *p = encode_heap_oop(v);
288 }
289 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
290
291 // Store heap oop as is for volatile fields.
292 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
293 OrderAccess::release_store_ptr(p, v);
294 }
295 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
296 narrowOop v) {
297 OrderAccess::release_store(p, v);
298 }
299
300 inline void oopDesc::release_encode_store_heap_oop_not_null(
301 volatile narrowOop* p, oop v) {
302 // heap oop is not pointer sized.
303 OrderAccess::release_store(p, encode_heap_oop_not_null(v));
304 }
305
306 inline void oopDesc::release_encode_store_heap_oop_not_null(
307 volatile oop* p, oop v) {
308 OrderAccess::release_store_ptr(p, v);
309 }
310
311 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
312 oop v) {
313 OrderAccess::release_store_ptr(p, v);
314 }
315 inline void oopDesc::release_encode_store_heap_oop(
316 volatile narrowOop* p, oop v) {
317 OrderAccess::release_store(p, encode_heap_oop(v));
318 }
319
320
321 // These functions are only used to exchange oop fields in instances,
322 // not headers.
323 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
324 oop result;
325 if (UseCompressedOops) {
326 // encode exchange value from oop to T
327 narrowOop val = encode_heap_oop(exchange_value);
328 narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
329 // decode old from T to oop
330 result = decode_heap_oop(old);
331 } else {
332 result = (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
333 }
334 #if INCLUDE_ALL_GCS
335 if (UseShenandoahGC) {
336 if (exchange_value != NULL) {
337 ShenandoahBarrierSet::barrier_set()->storeval_barrier(exchange_value);
338 }
339 result = ShenandoahBarrierSet::barrier_set()->load_reference_barrier(result);
340 }
341 #endif
342 return result;
343 }
344
345 // In order to put or get a field out of an instance, must first check
346 // if the field has been compressed and uncompress it.
347 inline oop oopDesc::obj_field(int offset) const {
348 oop obj = UseCompressedOops ?
349 load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :
350 load_decode_heap_oop(obj_field_addr<oop>(offset));
351 #if INCLUDE_ALL_GCS
352 if (UseShenandoahGC) {
353 obj = ShenandoahBarrierSet::barrier_set()->load_reference_barrier(obj);
354 }
355 #endif
356 return obj;
357 }
358 inline volatile oop oopDesc::obj_field_volatile(int offset) const {
359 volatile oop value = obj_field(offset);
360 OrderAccess::acquire();
361 return value;
362 }
363 inline void oopDesc::obj_field_put(int offset, oop value) {
364 UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
365 oop_store(obj_field_addr<oop>(offset), value);
366 }
367
368 inline Metadata* oopDesc::metadata_field(int offset) const {
369 return *metadata_field_addr(offset);
370 }
371
372 inline void oopDesc::metadata_field_put(int offset, Metadata* value) {
373 *metadata_field_addr(offset) = value;
374 }
375
376 inline void oopDesc::obj_field_put_raw(int offset, oop value) {
377 UseCompressedOops ?
378 encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
379 encode_store_heap_oop(obj_field_addr<oop>(offset), value);
380 }
381 inline void oopDesc::obj_field_put_volatile(int offset, oop value) {
382 OrderAccess::release();
383 obj_field_put(offset, value);
384 OrderAccess::fence();
385 }
386
387 inline jbyte oopDesc::byte_field(int offset) const { return (jbyte) *byte_field_addr(offset); }
388 inline void oopDesc::byte_field_put(int offset, jbyte contents) { *byte_field_addr(offset) = (jint) contents; }
389
390 inline jboolean oopDesc::bool_field(int offset) const { return (jboolean) *bool_field_addr(offset); }
391 inline void oopDesc::bool_field_put(int offset, jboolean contents) { *bool_field_addr(offset) = (( (jint) contents) & 1); }
392
393 inline jchar oopDesc::char_field(int offset) const { return (jchar) *char_field_addr(offset); }
394 inline void oopDesc::char_field_put(int offset, jchar contents) { *char_field_addr(offset) = (jint) contents; }
395
396 inline jint oopDesc::int_field(int offset) const { return *int_field_addr(offset); }
397 inline void oopDesc::int_field_put(int offset, jint contents) { *int_field_addr(offset) = contents; }
398
399 inline jshort oopDesc::short_field(int offset) const { return (jshort) *short_field_addr(offset); }
400 inline void oopDesc::short_field_put(int offset, jshort contents) { *short_field_addr(offset) = (jint) contents;}
401
402 inline jlong oopDesc::long_field(int offset) const { return *long_field_addr(offset); }
403 inline void oopDesc::long_field_put(int offset, jlong contents) { *long_field_addr(offset) = contents; }
404
405 inline jfloat oopDesc::float_field(int offset) const { return *float_field_addr(offset); }
406 inline void oopDesc::float_field_put(int offset, jfloat contents) { *float_field_addr(offset) = contents; }
407
408 inline jdouble oopDesc::double_field(int offset) const { return *double_field_addr(offset); }
409 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
410
411 inline address oopDesc::address_field(int offset) const { return *address_field_addr(offset); }
412 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
413
414 inline oop oopDesc::obj_field_acquire(int offset) const {
415 oop obj = UseCompressedOops ?
416 decode_heap_oop((narrowOop)
417 OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
418 : decode_heap_oop((oop)
419 OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
420 #if INCLUDE_ALL_GCS
421 if (UseShenandoahGC) {
422 obj = ShenandoahBarrierSet::barrier_set()->load_reference_barrier(obj);
423 }
424 #endif
425 return obj;
426 }
427 inline void oopDesc::release_obj_field_put(int offset, oop value) {
428 UseCompressedOops ?
429 oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
430 oop_store((volatile oop*) obj_field_addr<oop>(offset), value);
431 }
432
433 inline jbyte oopDesc::byte_field_acquire(int offset) const { return OrderAccess::load_acquire(byte_field_addr(offset)); }
434 inline void oopDesc::release_byte_field_put(int offset, jbyte contents) { OrderAccess::release_store(byte_field_addr(offset), contents); }
435
436 inline jboolean oopDesc::bool_field_acquire(int offset) const { return OrderAccess::load_acquire(bool_field_addr(offset)); }
437 inline void oopDesc::release_bool_field_put(int offset, jboolean contents) { OrderAccess::release_store(bool_field_addr(offset), (contents & 1)); }
438
439 inline jchar oopDesc::char_field_acquire(int offset) const { return OrderAccess::load_acquire(char_field_addr(offset)); }
440 inline void oopDesc::release_char_field_put(int offset, jchar contents) { OrderAccess::release_store(char_field_addr(offset), contents); }
441
442 inline jint oopDesc::int_field_acquire(int offset) const { return OrderAccess::load_acquire(int_field_addr(offset)); }
443 inline void oopDesc::release_int_field_put(int offset, jint contents) { OrderAccess::release_store(int_field_addr(offset), contents); }
444
445 inline jshort oopDesc::short_field_acquire(int offset) const { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
446 inline void oopDesc::release_short_field_put(int offset, jshort contents) { OrderAccess::release_store(short_field_addr(offset), contents); }
447
448 inline jlong oopDesc::long_field_acquire(int offset) const { return OrderAccess::load_acquire(long_field_addr(offset)); }
449 inline void oopDesc::release_long_field_put(int offset, jlong contents) { OrderAccess::release_store(long_field_addr(offset), contents); }
450
451 inline jfloat oopDesc::float_field_acquire(int offset) const { return OrderAccess::load_acquire(float_field_addr(offset)); }
452 inline void oopDesc::release_float_field_put(int offset, jfloat contents) { OrderAccess::release_store(float_field_addr(offset), contents); }
453
454 inline jdouble oopDesc::double_field_acquire(int offset) const { return OrderAccess::load_acquire(double_field_addr(offset)); }
455 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
456
457 inline address oopDesc::address_field_acquire(int offset) const { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); }
458 inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); }
459
460 inline int oopDesc::size_given_klass(Klass* klass) {
461 int lh = klass->layout_helper();
462 int s;
463
464 // lh is now a value computed at class initialization that may hint
465 // at the size. For instances, this is positive and equal to the
466 // size. For arrays, this is negative and provides log2 of the
467 // array element size. For other oops, it is zero and thus requires
468 // a virtual call.
469 //
470 // We go to all this trouble because the size computation is at the
471 // heart of phase 2 of mark-compaction, and called for every object,
472 // alive or dead. So the speed here is equal in importance to the
473 // speed of allocation.
474
475 if (lh > Klass::_lh_neutral_value) {
476 if (!Klass::layout_helper_needs_slow_path(lh)) {
477 s = lh >> LogHeapWordSize; // deliver size scaled by wordSize
478 } else {
479 s = klass->oop_size(this);
480 }
481 } else if (lh <= Klass::_lh_neutral_value) {
482 // The most common case is instances; fall through if so.
483 if (lh < Klass::_lh_neutral_value) {
484 // Second most common case is arrays. We have to fetch the
485 // length of the array, shift (multiply) it appropriately,
486 // up to wordSize, add the header, and align to object size.
487 size_t size_in_bytes;
488 #ifdef _M_IA64
489 // The Windows Itanium Aug 2002 SDK hoists this load above
490 // the check for s < 0. An oop at the end of the heap will
491 // cause an access violation if this load is performed on a non
492 // array oop. Making the reference volatile prohibits this.
493 // (%%% please explain by what magic the length is actually fetched!)
494 volatile int *array_length;
495 array_length = (volatile int *)( (intptr_t)this +
496 arrayOopDesc::length_offset_in_bytes() );
497 assert(array_length > 0, "Integer arithmetic problem somewhere");
498 // Put into size_t to avoid overflow.
499 size_in_bytes = (size_t) array_length;
500 size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
501 #else
502 size_t array_length = (size_t) ((arrayOop)this)->length();
503 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
504 #endif
505 size_in_bytes += Klass::layout_helper_header_size(lh);
506
507 // This code could be simplified, but by keeping array_header_in_bytes
508 // in units of bytes and doing it this way we can round up just once,
509 // skipping the intermediate round to HeapWordSize. Cast the result
510 // of round_to to size_t to guarantee unsigned division == right shift.
511 s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
512 HeapWordSize);
513
514 // UseParNewGC, UseParallelGC and UseG1GC can change the length field
515 // of an "old copy" of an object array in the young gen so it indicates
516 // the grey portion of an already copied array. This will cause the first
517 // disjunct below to fail if the two comparands are computed across such
518 // a concurrent change.
519 // UseParNewGC also runs with promotion labs (which look like int
520 // filler arrays) which are subject to changing their declared size
521 // when finally retiring a PLAB; this also can cause the first disjunct
522 // to fail for another worker thread that is concurrently walking the block
523 // offset table. Both these invariant failures are benign for their
524 // current uses; we relax the assertion checking to cover these two cases below:
525 // is_objArray() && is_forwarded() // covers first scenario above
526 // || is_typeArray() // covers second scenario above
527 // If and when UseParallelGC uses the same obj array oop stealing/chunking
528 // technique, we will need to suitably modify the assertion.
529 assert((s == klass->oop_size(this)) ||
530 (Universe::heap()->is_gc_active() &&
531 ((is_typeArray() && UseParNewGC) ||
532 (is_objArray() && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))),
533 "wrong array object size");
534 } else {
535 // Must be zero, so bite the bullet and take the virtual call.
536 s = klass->oop_size(this);
537 }
538 }
539
540 assert(s % MinObjAlignment == 0, "alignment check");
541 assert(s > 0, "Bad size calculated");
542 return s;
543 }
544
545
546 inline int oopDesc::size() {
547 return size_given_klass(klass());
548 }
549
550 inline void update_barrier_set(void* p, oop v, bool release = false) {
551 assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
552 oopDesc::bs()->write_ref_field(p, v, release);
553 }
554
555 template <class T> inline void update_barrier_set_pre(T* p, oop v) {
556 oopDesc::bs()->write_ref_field_pre(p, v);
557 }
558
559 template <class T> inline void oop_store(T* p, oop v) {
560 if (always_do_update_barrier) {
561 oop_store((volatile T*)p, v);
562 } else {
563 update_barrier_set_pre(p, v);
564 oopDesc::encode_store_heap_oop(p, v);
565 // always_do_update_barrier == false =>
566 // Either we are at a safepoint (in GC) or CMS is not used. In both
567 // cases it's unnecessary to mark the card as dirty with release sematics.
568 update_barrier_set((void*)p, v, false /* release */); // cast away type
569 }
570 }
571
572 template <class T> inline void oop_store(volatile T* p, oop v) {
573 update_barrier_set_pre((T*)p, v); // cast away volatile
574 // Used by release_obj_field_put, so use release_store_ptr.
575 oopDesc::release_encode_store_heap_oop(p, v);
576 // When using CMS we must mark the card corresponding to p as dirty
577 // with release sematics to prevent that CMS sees the dirty card but
578 // not the new value v at p due to reordering of the two
579 // stores. Note that CMS has a concurrent precleaning phase, where
580 // it reads the card table while the Java threads are running.
581 update_barrier_set((void*)p, v, true /* release */); // cast away type
582 }
583
584 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
585 // (without having to remember the function name this calls).
586 inline void oop_store_raw(HeapWord* addr, oop value) {
587 if (UseCompressedOops) {
588 oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
589 } else {
590 oopDesc::encode_store_heap_oop((oop*)addr, value);
591 }
592 }
593
594 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
595 volatile HeapWord *dest,
596 oop compare_value,
597 bool prebarrier) {
598 #if INCLUDE_ALL_GCS
599 if (UseShenandoahGC && ShenandoahCASBarrier) {
600 return ShenandoahBarrierSet::barrier_set()->oop_atomic_cmpxchg_in_heap(exchange_value, dest, compare_value);
601 }
602 #endif
603 if (UseCompressedOops) {
604 if (prebarrier) {
605 update_barrier_set_pre((narrowOop*)dest, exchange_value);
606 }
607 // encode exchange and compare value from oop to T
608 narrowOop val = encode_heap_oop(exchange_value);
609 narrowOop cmp = encode_heap_oop(compare_value);
610
611 narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
612 // decode old from T to oop
613 return decode_heap_oop(old);
614 } else {
615 if (prebarrier) {
616 update_barrier_set_pre((oop*)dest, exchange_value);
617 }
618 return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
619 }
620 }
621
622 // Used only for markSweep, scavenging
623 inline bool oopDesc::is_gc_marked() const {
624 return mark()->is_marked();
625 }
626
627 inline bool oopDesc::is_locked() const {
628 return mark()->is_locked();
629 }
630
631 inline bool oopDesc::is_unlocked() const {
632 return mark()->is_unlocked();
633 }
634
635 inline bool oopDesc::has_bias_pattern() const {
636 return mark()->has_bias_pattern();
637 }
638
639
640 // used only for asserts
641 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
642 oop obj = (oop) this;
643 if (!check_obj_alignment(obj)) return false;
644 if (!Universe::heap()->is_in_reserved(obj)) return false;
645 // obj is aligned and accessible in heap
646 if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
647
648 // Header verification: the mark is typically non-NULL. If we're
649 // at a safepoint, it must not be null.
650 // Outside of a safepoint, the header could be changing (for example,
651 // another thread could be inflating a lock on this object).
652 if (ignore_mark_word) {
653 return true;
654 }
655 if (mark() != NULL) {
656 return true;
657 }
658 return !SafepointSynchronize::is_at_safepoint();
659 }
660
661
662 // used only for asserts
663 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
664 return this == NULL ? true : is_oop(ignore_mark_word);
665 }
666
667 #ifndef PRODUCT
668 // used only for asserts
669 inline bool oopDesc::is_unlocked_oop() const {
670 if (!Universe::heap()->is_in_reserved(this)) return false;
671 return mark()->is_unlocked();
672 }
673 #endif // PRODUCT
674
675 inline void oopDesc::follow_contents(void) {
676 assert (is_gc_marked(), "should be marked");
677 klass()->oop_follow_contents(this);
678 }
679
680 // Used by scavengers
681
682 inline bool oopDesc::is_forwarded() const {
683 // The extra heap check is needed since the obj might be locked, in which case the
684 // mark would point to a stack location and have the sentinel bit cleared
685 return mark()->is_marked();
686 }
687
688 // Used by scavengers
689 inline void oopDesc::forward_to(oop p) {
690 assert(check_obj_alignment(p),
691 "forwarding to something not aligned");
692 assert(Universe::heap()->is_in_reserved(p),
693 "forwarding to something not in heap");
694 markOop m = markOopDesc::encode_pointer_as_mark(p);
695 assert(m->decode_pointer() == p, "encoding must be reversable");
696 set_mark(m);
697 }
698
699 // Used by parallel scavengers
700 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
701 assert(check_obj_alignment(p),
702 "forwarding to something not aligned");
703 assert(Universe::heap()->is_in_reserved(p),
704 "forwarding to something not in heap");
705 markOop m = markOopDesc::encode_pointer_as_mark(p);
706 assert(m->decode_pointer() == p, "encoding must be reversable");
707 return cas_set_mark(m, compare) == compare;
708 }
709
710 // Note that the forwardee is not the same thing as the displaced_mark.
711 // The forwardee is used when copying during scavenge and mark-sweep.
712 // It does need to clear the low two locking- and GC-related bits.
713 inline oop oopDesc::forwardee() const {
714 return (oop) mark()->decode_pointer();
715 }
716
717 inline bool oopDesc::has_displaced_mark() const {
718 return mark()->has_displaced_mark_helper();
719 }
720
721 inline markOop oopDesc::displaced_mark() const {
722 return mark()->displaced_mark_helper();
723 }
724
725 inline void oopDesc::set_displaced_mark(markOop m) {
726 mark()->set_displaced_mark_helper(m);
727 }
728
729 // The following method needs to be MT safe.
730 inline uint oopDesc::age() const {
731 assert(!is_forwarded(), "Attempt to read age from forwarded mark");
732 if (has_displaced_mark()) {
733 return displaced_mark()->age();
734 } else {
735 return mark()->age();
736 }
737 }
738
739 inline void oopDesc::incr_age() {
740 assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
741 if (has_displaced_mark()) {
742 set_displaced_mark(displaced_mark()->incr_age());
743 } else {
744 set_mark(mark()->incr_age());
745 }
746 }
747
748
749 inline intptr_t oopDesc::identity_hash() {
750 // Fast case; if the object is unlocked and the hash value is set, no locking is needed
751 // Note: The mark must be read into local variable to avoid concurrent updates.
752 markOop mrk = mark();
753 if (mrk->is_unlocked() && !mrk->has_no_hash()) {
754 return mrk->hash();
755 } else if (mrk->is_marked()) {
756 return mrk->hash();
757 } else {
758 return slow_identity_hash();
759 }
760 }
761
762 inline int oopDesc::adjust_pointers() {
763 debug_only(int check_size = size());
764 int s = klass()->oop_adjust_pointers(this);
765 assert(s == check_size, "should be the same");
766 return s;
767 }
768
769 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
770 \
771 inline int oopDesc::oop_iterate(OopClosureType* blk) { \
772 SpecializationStats::record_call(); \
773 return klass()->oop_oop_iterate##nv_suffix(this, blk); \
774 } \
775 \
776 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \
777 SpecializationStats::record_call(); \
778 return klass()->oop_oop_iterate##nv_suffix##_m(this, blk, mr); \
779 }
780
781
782 inline int oopDesc::oop_iterate_no_header(OopClosure* blk) {
783 // The NoHeaderExtendedOopClosure wraps the OopClosure and proxies all
784 // the do_oop calls, but turns off all other features in ExtendedOopClosure.
785 NoHeaderExtendedOopClosure cl(blk);
786 return oop_iterate(&cl);
787 }
788
789 inline int oopDesc::oop_iterate_no_header(OopClosure* blk, MemRegion mr) {
790 NoHeaderExtendedOopClosure cl(blk);
791 return oop_iterate(&cl, mr);
792 }
793
794 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
795 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN)
796
797 #if INCLUDE_ALL_GCS
798 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
799 \
800 inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) { \
801 SpecializationStats::record_call(); \
802 return klass()->oop_oop_iterate_backwards##nv_suffix(this, blk); \
803 }
804
805 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN)
806 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN)
807 #endif // INCLUDE_ALL_GCS
808
809 #endif // SHARE_VM_OOPS_OOP_INLINE_HPP