Thu, 12 Oct 2017 21:27:07 +0800
merge
1 /*
2 * Copyright (c) 1997, 2014, 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 */
25 /*
26 * This file has been modified by Loongson Technology in 2015. These
27 * modifications are Copyright (c) 2015 Loongson Technology, and are made
28 * available on the same license terms set forth above.
29 */
31 #ifndef SHARE_VM_OOPS_OOP_INLINE_HPP
32 #define SHARE_VM_OOPS_OOP_INLINE_HPP
34 #include "gc_implementation/shared/ageTable.hpp"
35 #include "gc_implementation/shared/markSweep.inline.hpp"
36 #include "gc_interface/collectedHeap.inline.hpp"
37 #include "memory/barrierSet.inline.hpp"
38 #include "memory/cardTableModRefBS.hpp"
39 #include "memory/genCollectedHeap.hpp"
40 #include "memory/generation.hpp"
41 #include "memory/specialized_oop_closures.hpp"
42 #include "oops/arrayKlass.hpp"
43 #include "oops/arrayOop.hpp"
44 #include "oops/klass.inline.hpp"
45 #include "oops/markOop.inline.hpp"
46 #include "oops/oop.hpp"
47 #include "runtime/atomic.inline.hpp"
48 #include "runtime/orderAccess.inline.hpp"
49 #include "runtime/os.hpp"
50 #include "utilities/macros.hpp"
51 #ifdef TARGET_ARCH_x86
52 # include "bytes_x86.hpp"
53 #endif
54 #ifdef TARGET_ARCH_sparc
55 # include "bytes_sparc.hpp"
56 #endif
57 #ifdef TARGET_ARCH_zero
58 # include "bytes_zero.hpp"
59 #endif
60 #ifdef TARGET_ARCH_arm
61 # include "bytes_arm.hpp"
62 #endif
63 #ifdef TARGET_ARCH_ppc
64 # include "bytes_ppc.hpp"
65 #endif
66 #ifdef TARGET_ARCH_mips
67 # include "bytes_mips.hpp"
68 #endif
70 // Implementation of all inlined member functions defined in oop.hpp
71 // We need a separate file to avoid circular references
73 inline void oopDesc::release_set_mark(markOop m) {
74 OrderAccess::release_store_ptr(&_mark, m);
75 }
77 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
78 return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
79 }
81 inline Klass* oopDesc::klass() const {
82 if (UseCompressedClassPointers) {
83 return Klass::decode_klass_not_null(_metadata._compressed_klass);
84 } else {
85 return _metadata._klass;
86 }
87 }
89 inline Klass* oopDesc::klass_or_null() const volatile {
90 // can be NULL in CMS
91 if (UseCompressedClassPointers) {
92 return Klass::decode_klass(_metadata._compressed_klass);
93 } else {
94 return _metadata._klass;
95 }
96 }
98 inline int oopDesc::klass_gap_offset_in_bytes() {
99 assert(UseCompressedClassPointers, "only applicable to compressed klass pointers");
100 return oopDesc::klass_offset_in_bytes() + sizeof(narrowKlass);
101 }
103 inline Klass** oopDesc::klass_addr() {
104 // Only used internally and with CMS and will not work with
105 // UseCompressedOops
106 assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers");
107 return (Klass**) &_metadata._klass;
108 }
110 inline narrowKlass* oopDesc::compressed_klass_addr() {
111 assert(UseCompressedClassPointers, "only called by compressed klass pointers");
112 return &_metadata._compressed_klass;
113 }
115 inline void oopDesc::set_klass(Klass* k) {
116 // since klasses are promoted no store check is needed
117 assert(Universe::is_bootstrapping() || k != NULL, "must be a real Klass*");
118 assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass*");
119 if (UseCompressedClassPointers) {
120 *compressed_klass_addr() = Klass::encode_klass_not_null(k);
121 } else {
122 *klass_addr() = k;
123 }
124 }
126 inline int oopDesc::klass_gap() const {
127 return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
128 }
130 inline void oopDesc::set_klass_gap(int v) {
131 if (UseCompressedClassPointers) {
132 *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
133 }
134 }
136 inline void oopDesc::set_klass_to_list_ptr(oop k) {
137 // This is only to be used during GC, for from-space objects, so no
138 // barrier is needed.
139 if (UseCompressedClassPointers) {
140 _metadata._compressed_klass = (narrowKlass)encode_heap_oop(k); // may be null (parnew overflow handling)
141 } else {
142 _metadata._klass = (Klass*)(address)k;
143 }
144 }
146 inline oop oopDesc::list_ptr_from_klass() {
147 // This is only to be used during GC, for from-space objects.
148 if (UseCompressedClassPointers) {
149 return decode_heap_oop((narrowOop)_metadata._compressed_klass);
150 } else {
151 // Special case for GC
152 return (oop)(address)_metadata._klass;
153 }
154 }
156 inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); }
158 inline bool oopDesc::is_a(Klass* k) const { return klass()->is_subtype_of(k); }
160 inline bool oopDesc::is_instance() const { return klass()->oop_is_instance(); }
161 inline bool oopDesc::is_instanceClassLoader() const { return klass()->oop_is_instanceClassLoader(); }
162 inline bool oopDesc::is_instanceMirror() const { return klass()->oop_is_instanceMirror(); }
163 inline bool oopDesc::is_instanceRef() const { return klass()->oop_is_instanceRef(); }
164 inline bool oopDesc::is_array() const { return klass()->oop_is_array(); }
165 inline bool oopDesc::is_objArray() const { return klass()->oop_is_objArray(); }
166 inline bool oopDesc::is_typeArray() const { return klass()->oop_is_typeArray(); }
168 inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; }
170 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
171 inline Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); }
172 inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); }
173 inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); }
174 inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); }
175 inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); }
176 inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); }
177 inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); }
178 inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); }
179 inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
180 inline address* oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
183 // Functions for getting and setting oops within instance objects.
184 // If the oops are compressed, the type passed to these overloaded functions
185 // is narrowOop. All functions are overloaded so they can be called by
186 // template functions without conditionals (the compiler instantiates via
187 // the right type and inlines the appopriate code).
189 inline bool oopDesc::is_null(oop obj) { return obj == NULL; }
190 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
192 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
193 // offset from the heap base. Saving the check for null can save instructions
194 // in inner GC loops so these are separated.
196 inline bool check_obj_alignment(oop obj) {
197 return cast_from_oop<intptr_t>(obj) % MinObjAlignmentInBytes == 0;
198 }
200 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
201 assert(!is_null(v), "oop value can never be zero");
202 assert(check_obj_alignment(v), "Address not aligned");
203 assert(Universe::heap()->is_in_reserved(v), "Address not in heap");
204 address base = Universe::narrow_oop_base();
205 int shift = Universe::narrow_oop_shift();
206 uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1));
207 assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
208 uint64_t result = pd >> shift;
209 assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
210 assert(decode_heap_oop(result) == v, "reversibility");
211 return (narrowOop)result;
212 }
214 inline narrowOop oopDesc::encode_heap_oop(oop v) {
215 return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
216 }
218 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
219 assert(!is_null(v), "narrow oop value can never be zero");
220 address base = Universe::narrow_oop_base();
221 int shift = Universe::narrow_oop_shift();
222 oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift));
223 assert(check_obj_alignment(result), err_msg("address not aligned: " INTPTR_FORMAT, p2i((void*) result)));
224 return result;
225 }
227 inline oop oopDesc::decode_heap_oop(narrowOop v) {
228 return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
229 }
231 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
232 inline oop oopDesc::decode_heap_oop(oop v) { return v; }
234 // Load an oop out of the Java heap as is without decoding.
235 // Called by GC to check for null before decoding.
236 inline oop oopDesc::load_heap_oop(oop* p) { return *p; }
237 inline narrowOop oopDesc::load_heap_oop(narrowOop* p) { return *p; }
239 // Load and decode an oop out of the Java heap into a wide oop.
240 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p) { return *p; }
241 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
242 return decode_heap_oop_not_null(*p);
243 }
245 // Load and decode an oop out of the heap accepting null
246 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
247 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
248 return decode_heap_oop(*p);
249 }
251 // Store already encoded heap oop into the heap.
252 inline void oopDesc::store_heap_oop(oop* p, oop v) { *p = v; }
253 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v) { *p = v; }
255 // Encode and store a heap oop.
256 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
257 *p = encode_heap_oop_not_null(v);
258 }
259 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
261 // Encode and store a heap oop allowing for null.
262 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
263 *p = encode_heap_oop(v);
264 }
265 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
267 // Store heap oop as is for volatile fields.
268 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
269 OrderAccess::release_store_ptr(p, v);
270 }
271 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
272 narrowOop v) {
273 OrderAccess::release_store(p, v);
274 }
276 inline void oopDesc::release_encode_store_heap_oop_not_null(
277 volatile narrowOop* p, oop v) {
278 // heap oop is not pointer sized.
279 OrderAccess::release_store(p, encode_heap_oop_not_null(v));
280 }
282 inline void oopDesc::release_encode_store_heap_oop_not_null(
283 volatile oop* p, oop v) {
284 OrderAccess::release_store_ptr(p, v);
285 }
287 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
288 oop v) {
289 OrderAccess::release_store_ptr(p, v);
290 }
291 inline void oopDesc::release_encode_store_heap_oop(
292 volatile narrowOop* p, oop v) {
293 OrderAccess::release_store(p, encode_heap_oop(v));
294 }
297 // These functions are only used to exchange oop fields in instances,
298 // not headers.
299 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
300 if (UseCompressedOops) {
301 // encode exchange value from oop to T
302 narrowOop val = encode_heap_oop(exchange_value);
303 narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
304 // decode old from T to oop
305 return decode_heap_oop(old);
306 } else {
307 return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
308 }
309 }
311 // In order to put or get a field out of an instance, must first check
312 // if the field has been compressed and uncompress it.
313 inline oop oopDesc::obj_field(int offset) const {
314 return UseCompressedOops ?
315 load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :
316 load_decode_heap_oop(obj_field_addr<oop>(offset));
317 }
318 inline volatile oop oopDesc::obj_field_volatile(int offset) const {
319 volatile oop value = obj_field(offset);
320 OrderAccess::acquire();
321 return value;
322 }
323 inline void oopDesc::obj_field_put(int offset, oop value) {
324 UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
325 oop_store(obj_field_addr<oop>(offset), value);
326 }
328 inline Metadata* oopDesc::metadata_field(int offset) const {
329 return *metadata_field_addr(offset);
330 }
332 inline void oopDesc::metadata_field_put(int offset, Metadata* value) {
333 *metadata_field_addr(offset) = value;
334 }
336 inline void oopDesc::obj_field_put_raw(int offset, oop value) {
337 UseCompressedOops ?
338 encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
339 encode_store_heap_oop(obj_field_addr<oop>(offset), value);
340 }
341 inline void oopDesc::obj_field_put_volatile(int offset, oop value) {
342 OrderAccess::release();
343 obj_field_put(offset, value);
344 OrderAccess::fence();
345 }
347 inline jbyte oopDesc::byte_field(int offset) const { return (jbyte) *byte_field_addr(offset); }
348 inline void oopDesc::byte_field_put(int offset, jbyte contents) { *byte_field_addr(offset) = (jint) contents; }
350 inline jboolean oopDesc::bool_field(int offset) const { return (jboolean) *bool_field_addr(offset); }
351 inline void oopDesc::bool_field_put(int offset, jboolean contents) { *bool_field_addr(offset) = (jint) contents; }
353 inline jchar oopDesc::char_field(int offset) const { return (jchar) *char_field_addr(offset); }
354 inline void oopDesc::char_field_put(int offset, jchar contents) { *char_field_addr(offset) = (jint) contents; }
356 inline jint oopDesc::int_field(int offset) const { return *int_field_addr(offset); }
357 inline void oopDesc::int_field_put(int offset, jint contents) { *int_field_addr(offset) = contents; }
359 inline jshort oopDesc::short_field(int offset) const { return (jshort) *short_field_addr(offset); }
360 inline void oopDesc::short_field_put(int offset, jshort contents) { *short_field_addr(offset) = (jint) contents;}
362 inline jlong oopDesc::long_field(int offset) const { return *long_field_addr(offset); }
363 inline void oopDesc::long_field_put(int offset, jlong contents) { *long_field_addr(offset) = contents; }
365 inline jfloat oopDesc::float_field(int offset) const { return *float_field_addr(offset); }
366 inline void oopDesc::float_field_put(int offset, jfloat contents) { *float_field_addr(offset) = contents; }
368 inline jdouble oopDesc::double_field(int offset) const { return *double_field_addr(offset); }
369 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
371 inline address oopDesc::address_field(int offset) const { return *address_field_addr(offset); }
372 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
374 inline oop oopDesc::obj_field_acquire(int offset) const {
375 return UseCompressedOops ?
376 decode_heap_oop((narrowOop)
377 OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
378 : decode_heap_oop((oop)
379 OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
380 }
381 inline void oopDesc::release_obj_field_put(int offset, oop value) {
382 UseCompressedOops ?
383 oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
384 oop_store((volatile oop*) obj_field_addr<oop>(offset), value);
385 }
387 inline jbyte oopDesc::byte_field_acquire(int offset) const { return OrderAccess::load_acquire(byte_field_addr(offset)); }
388 inline void oopDesc::release_byte_field_put(int offset, jbyte contents) { OrderAccess::release_store(byte_field_addr(offset), contents); }
390 inline jboolean oopDesc::bool_field_acquire(int offset) const { return OrderAccess::load_acquire(bool_field_addr(offset)); }
391 inline void oopDesc::release_bool_field_put(int offset, jboolean contents) { OrderAccess::release_store(bool_field_addr(offset), contents); }
393 inline jchar oopDesc::char_field_acquire(int offset) const { return OrderAccess::load_acquire(char_field_addr(offset)); }
394 inline void oopDesc::release_char_field_put(int offset, jchar contents) { OrderAccess::release_store(char_field_addr(offset), contents); }
396 inline jint oopDesc::int_field_acquire(int offset) const { return OrderAccess::load_acquire(int_field_addr(offset)); }
397 inline void oopDesc::release_int_field_put(int offset, jint contents) { OrderAccess::release_store(int_field_addr(offset), contents); }
399 inline jshort oopDesc::short_field_acquire(int offset) const { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
400 inline void oopDesc::release_short_field_put(int offset, jshort contents) { OrderAccess::release_store(short_field_addr(offset), contents); }
402 inline jlong oopDesc::long_field_acquire(int offset) const { return OrderAccess::load_acquire(long_field_addr(offset)); }
403 inline void oopDesc::release_long_field_put(int offset, jlong contents) { OrderAccess::release_store(long_field_addr(offset), contents); }
405 inline jfloat oopDesc::float_field_acquire(int offset) const { return OrderAccess::load_acquire(float_field_addr(offset)); }
406 inline void oopDesc::release_float_field_put(int offset, jfloat contents) { OrderAccess::release_store(float_field_addr(offset), contents); }
408 inline jdouble oopDesc::double_field_acquire(int offset) const { return OrderAccess::load_acquire(double_field_addr(offset)); }
409 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
411 inline address oopDesc::address_field_acquire(int offset) const { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); }
412 inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); }
414 inline int oopDesc::size_given_klass(Klass* klass) {
415 int lh = klass->layout_helper();
416 int s;
418 // lh is now a value computed at class initialization that may hint
419 // at the size. For instances, this is positive and equal to the
420 // size. For arrays, this is negative and provides log2 of the
421 // array element size. For other oops, it is zero and thus requires
422 // a virtual call.
423 //
424 // We go to all this trouble because the size computation is at the
425 // heart of phase 2 of mark-compaction, and called for every object,
426 // alive or dead. So the speed here is equal in importance to the
427 // speed of allocation.
429 if (lh > Klass::_lh_neutral_value) {
430 if (!Klass::layout_helper_needs_slow_path(lh)) {
431 s = lh >> LogHeapWordSize; // deliver size scaled by wordSize
432 } else {
433 s = klass->oop_size(this);
434 }
435 } else if (lh <= Klass::_lh_neutral_value) {
436 // The most common case is instances; fall through if so.
437 if (lh < Klass::_lh_neutral_value) {
438 // Second most common case is arrays. We have to fetch the
439 // length of the array, shift (multiply) it appropriately,
440 // up to wordSize, add the header, and align to object size.
441 size_t size_in_bytes;
442 #ifdef _M_IA64
443 // The Windows Itanium Aug 2002 SDK hoists this load above
444 // the check for s < 0. An oop at the end of the heap will
445 // cause an access violation if this load is performed on a non
446 // array oop. Making the reference volatile prohibits this.
447 // (%%% please explain by what magic the length is actually fetched!)
448 volatile int *array_length;
449 array_length = (volatile int *)( (intptr_t)this +
450 arrayOopDesc::length_offset_in_bytes() );
451 assert(array_length > 0, "Integer arithmetic problem somewhere");
452 // Put into size_t to avoid overflow.
453 size_in_bytes = (size_t) array_length;
454 size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
455 #else
456 size_t array_length = (size_t) ((arrayOop)this)->length();
457 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
458 #endif
459 size_in_bytes += Klass::layout_helper_header_size(lh);
461 // This code could be simplified, but by keeping array_header_in_bytes
462 // in units of bytes and doing it this way we can round up just once,
463 // skipping the intermediate round to HeapWordSize. Cast the result
464 // of round_to to size_t to guarantee unsigned division == right shift.
465 s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
466 HeapWordSize);
468 // UseParNewGC, UseParallelGC and UseG1GC can change the length field
469 // of an "old copy" of an object array in the young gen so it indicates
470 // the grey portion of an already copied array. This will cause the first
471 // disjunct below to fail if the two comparands are computed across such
472 // a concurrent change.
473 // UseParNewGC also runs with promotion labs (which look like int
474 // filler arrays) which are subject to changing their declared size
475 // when finally retiring a PLAB; this also can cause the first disjunct
476 // to fail for another worker thread that is concurrently walking the block
477 // offset table. Both these invariant failures are benign for their
478 // current uses; we relax the assertion checking to cover these two cases below:
479 // is_objArray() && is_forwarded() // covers first scenario above
480 // || is_typeArray() // covers second scenario above
481 // If and when UseParallelGC uses the same obj array oop stealing/chunking
482 // technique, we will need to suitably modify the assertion.
483 assert((s == klass->oop_size(this)) ||
484 (Universe::heap()->is_gc_active() &&
485 ((is_typeArray() && UseParNewGC) ||
486 (is_objArray() && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))),
487 "wrong array object size");
488 } else {
489 // Must be zero, so bite the bullet and take the virtual call.
490 s = klass->oop_size(this);
491 }
492 }
494 assert(s % MinObjAlignment == 0, "alignment check");
495 assert(s > 0, "Bad size calculated");
496 return s;
497 }
500 inline int oopDesc::size() {
501 return size_given_klass(klass());
502 }
504 inline void update_barrier_set(void* p, oop v, bool release = false) {
505 assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
506 oopDesc::bs()->write_ref_field(p, v, release);
507 }
509 template <class T> inline void update_barrier_set_pre(T* p, oop v) {
510 oopDesc::bs()->write_ref_field_pre(p, v);
511 }
513 template <class T> inline void oop_store(T* p, oop v) {
514 if (always_do_update_barrier) {
515 oop_store((volatile T*)p, v);
516 } else {
517 update_barrier_set_pre(p, v);
518 oopDesc::encode_store_heap_oop(p, v);
519 // always_do_update_barrier == false =>
520 // Either we are at a safepoint (in GC) or CMS is not used. In both
521 // cases it's unnecessary to mark the card as dirty with release sematics.
522 update_barrier_set((void*)p, v, false /* release */); // cast away type
523 }
524 }
526 template <class T> inline void oop_store(volatile T* p, oop v) {
527 update_barrier_set_pre((T*)p, v); // cast away volatile
528 // Used by release_obj_field_put, so use release_store_ptr.
529 oopDesc::release_encode_store_heap_oop(p, v);
530 // When using CMS we must mark the card corresponding to p as dirty
531 // with release sematics to prevent that CMS sees the dirty card but
532 // not the new value v at p due to reordering of the two
533 // stores. Note that CMS has a concurrent precleaning phase, where
534 // it reads the card table while the Java threads are running.
535 update_barrier_set((void*)p, v, true /* release */); // cast away type
536 }
538 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
539 // (without having to remember the function name this calls).
540 inline void oop_store_raw(HeapWord* addr, oop value) {
541 if (UseCompressedOops) {
542 oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
543 } else {
544 oopDesc::encode_store_heap_oop((oop*)addr, value);
545 }
546 }
548 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
549 volatile HeapWord *dest,
550 oop compare_value,
551 bool prebarrier) {
552 if (UseCompressedOops) {
553 if (prebarrier) {
554 update_barrier_set_pre((narrowOop*)dest, exchange_value);
555 }
556 // encode exchange and compare value from oop to T
557 narrowOop val = encode_heap_oop(exchange_value);
558 narrowOop cmp = encode_heap_oop(compare_value);
560 narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
561 // decode old from T to oop
562 return decode_heap_oop(old);
563 } else {
564 if (prebarrier) {
565 update_barrier_set_pre((oop*)dest, exchange_value);
566 }
567 return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
568 }
569 }
571 // Used only for markSweep, scavenging
572 inline bool oopDesc::is_gc_marked() const {
573 return mark()->is_marked();
574 }
576 inline bool oopDesc::is_locked() const {
577 return mark()->is_locked();
578 }
580 inline bool oopDesc::is_unlocked() const {
581 return mark()->is_unlocked();
582 }
584 inline bool oopDesc::has_bias_pattern() const {
585 return mark()->has_bias_pattern();
586 }
589 // used only for asserts
590 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
591 oop obj = (oop) this;
592 if (!check_obj_alignment(obj)) return false;
593 if (!Universe::heap()->is_in_reserved(obj)) return false;
594 // obj is aligned and accessible in heap
595 if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
597 // Header verification: the mark is typically non-NULL. If we're
598 // at a safepoint, it must not be null.
599 // Outside of a safepoint, the header could be changing (for example,
600 // another thread could be inflating a lock on this object).
601 if (ignore_mark_word) {
602 return true;
603 }
604 if (mark() != NULL) {
605 return true;
606 }
607 return !SafepointSynchronize::is_at_safepoint();
608 }
611 // used only for asserts
612 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
613 return this == NULL ? true : is_oop(ignore_mark_word);
614 }
616 #ifndef PRODUCT
617 // used only for asserts
618 inline bool oopDesc::is_unlocked_oop() const {
619 if (!Universe::heap()->is_in_reserved(this)) return false;
620 return mark()->is_unlocked();
621 }
622 #endif // PRODUCT
624 inline void oopDesc::follow_contents(void) {
625 assert (is_gc_marked(), "should be marked");
626 klass()->oop_follow_contents(this);
627 }
629 // Used by scavengers
631 inline bool oopDesc::is_forwarded() const {
632 // The extra heap check is needed since the obj might be locked, in which case the
633 // mark would point to a stack location and have the sentinel bit cleared
634 return mark()->is_marked();
635 }
637 // Used by scavengers
638 inline void oopDesc::forward_to(oop p) {
639 assert(check_obj_alignment(p),
640 "forwarding to something not aligned");
641 assert(Universe::heap()->is_in_reserved(p),
642 "forwarding to something not in heap");
643 markOop m = markOopDesc::encode_pointer_as_mark(p);
644 assert(m->decode_pointer() == p, "encoding must be reversable");
645 set_mark(m);
646 }
648 // Used by parallel scavengers
649 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
650 assert(check_obj_alignment(p),
651 "forwarding to something not aligned");
652 assert(Universe::heap()->is_in_reserved(p),
653 "forwarding to something not in heap");
654 markOop m = markOopDesc::encode_pointer_as_mark(p);
655 assert(m->decode_pointer() == p, "encoding must be reversable");
656 return cas_set_mark(m, compare) == compare;
657 }
659 // Note that the forwardee is not the same thing as the displaced_mark.
660 // The forwardee is used when copying during scavenge and mark-sweep.
661 // It does need to clear the low two locking- and GC-related bits.
662 inline oop oopDesc::forwardee() const {
663 return (oop) mark()->decode_pointer();
664 }
666 inline bool oopDesc::has_displaced_mark() const {
667 return mark()->has_displaced_mark_helper();
668 }
670 inline markOop oopDesc::displaced_mark() const {
671 return mark()->displaced_mark_helper();
672 }
674 inline void oopDesc::set_displaced_mark(markOop m) {
675 mark()->set_displaced_mark_helper(m);
676 }
678 // The following method needs to be MT safe.
679 inline uint oopDesc::age() const {
680 assert(!is_forwarded(), "Attempt to read age from forwarded mark");
681 if (has_displaced_mark()) {
682 return displaced_mark()->age();
683 } else {
684 return mark()->age();
685 }
686 }
688 inline void oopDesc::incr_age() {
689 assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
690 if (has_displaced_mark()) {
691 set_displaced_mark(displaced_mark()->incr_age());
692 } else {
693 set_mark(mark()->incr_age());
694 }
695 }
698 inline intptr_t oopDesc::identity_hash() {
699 // Fast case; if the object is unlocked and the hash value is set, no locking is needed
700 // Note: The mark must be read into local variable to avoid concurrent updates.
701 markOop mrk = mark();
702 if (mrk->is_unlocked() && !mrk->has_no_hash()) {
703 return mrk->hash();
704 } else if (mrk->is_marked()) {
705 return mrk->hash();
706 } else {
707 return slow_identity_hash();
708 }
709 }
711 inline int oopDesc::adjust_pointers() {
712 debug_only(int check_size = size());
713 int s = klass()->oop_adjust_pointers(this);
714 assert(s == check_size, "should be the same");
715 return s;
716 }
718 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
719 \
720 inline int oopDesc::oop_iterate(OopClosureType* blk) { \
721 SpecializationStats::record_call(); \
722 return klass()->oop_oop_iterate##nv_suffix(this, blk); \
723 } \
724 \
725 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \
726 SpecializationStats::record_call(); \
727 return klass()->oop_oop_iterate##nv_suffix##_m(this, blk, mr); \
728 }
731 inline int oopDesc::oop_iterate_no_header(OopClosure* blk) {
732 // The NoHeaderExtendedOopClosure wraps the OopClosure and proxies all
733 // the do_oop calls, but turns off all other features in ExtendedOopClosure.
734 NoHeaderExtendedOopClosure cl(blk);
735 return oop_iterate(&cl);
736 }
738 inline int oopDesc::oop_iterate_no_header(OopClosure* blk, MemRegion mr) {
739 NoHeaderExtendedOopClosure cl(blk);
740 return oop_iterate(&cl, mr);
741 }
743 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
744 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN)
746 #if INCLUDE_ALL_GCS
747 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \
748 \
749 inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) { \
750 SpecializationStats::record_call(); \
751 return klass()->oop_oop_iterate_backwards##nv_suffix(this, blk); \
752 }
754 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN)
755 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN)
756 #endif // INCLUDE_ALL_GCS
758 #endif // SHARE_VM_OOPS_OOP_INLINE_HPP