Tue, 24 Jun 2008 16:00:14 -0700
6718676: putback for 6604014 is incomplete
Reviewed-by: kvn, jrose
1 /*
2 * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 // Implementation of all inlined member functions defined in oop.hpp
26 // We need a separate file to avoid circular references
28 inline void oopDesc::release_set_mark(markOop m) {
29 OrderAccess::release_store_ptr(&_mark, m);
30 }
32 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) {
33 return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark);
34 }
36 inline klassOop oopDesc::klass() const {
37 if (UseCompressedOops) {
38 return (klassOop)decode_heap_oop_not_null(_metadata._compressed_klass);
39 } else {
40 return _metadata._klass;
41 }
42 }
44 inline klassOop oopDesc::klass_or_null() const volatile {
45 // can be NULL in CMS
46 if (UseCompressedOops) {
47 return (klassOop)decode_heap_oop(_metadata._compressed_klass);
48 } else {
49 return _metadata._klass;
50 }
51 }
53 inline int oopDesc::klass_gap_offset_in_bytes() {
54 assert(UseCompressedOops, "only applicable to compressed headers");
55 return oopDesc::klass_offset_in_bytes() + sizeof(narrowOop);
56 }
58 inline oop* oopDesc::klass_addr() {
59 // Only used internally and with CMS and will not work with
60 // UseCompressedOops
61 assert(!UseCompressedOops, "only supported with uncompressed oops");
62 return (oop*) &_metadata._klass;
63 }
65 inline narrowOop* oopDesc::compressed_klass_addr() {
66 assert(UseCompressedOops, "only called by compressed oops");
67 return (narrowOop*) &_metadata._compressed_klass;
68 }
70 inline void oopDesc::set_klass(klassOop k) {
71 // since klasses are promoted no store check is needed
72 assert(Universe::is_bootstrapping() || k != NULL, "must be a real klassOop");
73 assert(Universe::is_bootstrapping() || k->is_klass(), "not a klassOop");
74 if (UseCompressedOops) {
75 oop_store_without_check(compressed_klass_addr(), (oop)k);
76 } else {
77 oop_store_without_check(klass_addr(), (oop) k);
78 }
79 }
81 inline int oopDesc::klass_gap() const {
82 return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes());
83 }
85 inline void oopDesc::set_klass_gap(int v) {
86 if (UseCompressedOops) {
87 *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v;
88 }
89 }
91 inline void oopDesc::set_klass_to_list_ptr(oop k) {
92 // This is only to be used during GC, for from-space objects, so no
93 // barrier is needed.
94 if (UseCompressedOops) {
95 _metadata._compressed_klass = encode_heap_oop_not_null(k);
96 } else {
97 _metadata._klass = (klassOop)k;
98 }
99 }
101 inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); }
102 inline Klass* oopDesc::blueprint() const { return klass()->klass_part(); }
104 inline bool oopDesc::is_a(klassOop k) const { return blueprint()->is_subtype_of(k); }
106 inline bool oopDesc::is_instance() const { return blueprint()->oop_is_instance(); }
107 inline bool oopDesc::is_instanceRef() const { return blueprint()->oop_is_instanceRef(); }
108 inline bool oopDesc::is_array() const { return blueprint()->oop_is_array(); }
109 inline bool oopDesc::is_objArray() const { return blueprint()->oop_is_objArray(); }
110 inline bool oopDesc::is_typeArray() const { return blueprint()->oop_is_typeArray(); }
111 inline bool oopDesc::is_javaArray() const { return blueprint()->oop_is_javaArray(); }
112 inline bool oopDesc::is_symbol() const { return blueprint()->oop_is_symbol(); }
113 inline bool oopDesc::is_klass() const { return blueprint()->oop_is_klass(); }
114 inline bool oopDesc::is_thread() const { return blueprint()->oop_is_thread(); }
115 inline bool oopDesc::is_method() const { return blueprint()->oop_is_method(); }
116 inline bool oopDesc::is_constMethod() const { return blueprint()->oop_is_constMethod(); }
117 inline bool oopDesc::is_methodData() const { return blueprint()->oop_is_methodData(); }
118 inline bool oopDesc::is_constantPool() const { return blueprint()->oop_is_constantPool(); }
119 inline bool oopDesc::is_constantPoolCache() const { return blueprint()->oop_is_constantPoolCache(); }
120 inline bool oopDesc::is_compiledICHolder() const { return blueprint()->oop_is_compiledICHolder(); }
122 inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; }
124 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); }
125 inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); }
126 inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); }
127 inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); }
128 inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); }
129 inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); }
130 inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); }
131 inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); }
132 inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); }
133 inline address* oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); }
136 // Functions for getting and setting oops within instance objects.
137 // If the oops are compressed, the type passed to these overloaded functions
138 // is narrowOop. All functions are overloaded so they can be called by
139 // template functions without conditionals (the compiler instantiates via
140 // the right type and inlines the appopriate code).
142 inline bool oopDesc::is_null(oop obj) { return obj == NULL; }
143 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; }
145 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit
146 // offset from the heap base. Saving the check for null can save instructions
147 // in inner GC loops so these are separated.
149 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) {
150 assert(!is_null(v), "oop value can never be zero");
151 address heap_base = Universe::heap_base();
152 uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)heap_base, 1));
153 assert(OopEncodingHeapMax > pd, "change encoding max if new encoding");
154 uint64_t result = pd >> LogMinObjAlignmentInBytes;
155 assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow");
156 return (narrowOop)result;
157 }
159 inline narrowOop oopDesc::encode_heap_oop(oop v) {
160 return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v);
161 }
163 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) {
164 assert(!is_null(v), "narrow oop value can never be zero");
165 address heap_base = Universe::heap_base();
166 return (oop)(void*)((uintptr_t)heap_base + ((uintptr_t)v << LogMinObjAlignmentInBytes));
167 }
169 inline oop oopDesc::decode_heap_oop(narrowOop v) {
170 return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v);
171 }
173 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; }
174 inline oop oopDesc::decode_heap_oop(oop v) { return v; }
176 // Load an oop out of the Java heap as is without decoding.
177 // Called by GC to check for null before decoding.
178 inline oop oopDesc::load_heap_oop(oop* p) { return *p; }
179 inline narrowOop oopDesc::load_heap_oop(narrowOop* p) { return *p; }
181 // Load and decode an oop out of the Java heap into a wide oop.
182 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p) { return *p; }
183 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) {
184 return decode_heap_oop_not_null(*p);
185 }
187 // Load and decode an oop out of the heap accepting null
188 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; }
189 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) {
190 return decode_heap_oop(*p);
191 }
193 // Store already encoded heap oop into the heap.
194 inline void oopDesc::store_heap_oop(oop* p, oop v) { *p = v; }
195 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v) { *p = v; }
197 // Encode and store a heap oop.
198 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) {
199 *p = encode_heap_oop_not_null(v);
200 }
201 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; }
203 // Encode and store a heap oop allowing for null.
204 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) {
205 *p = encode_heap_oop(v);
206 }
207 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; }
209 // Store heap oop as is for volatile fields.
210 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) {
211 OrderAccess::release_store_ptr(p, v);
212 }
213 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p,
214 narrowOop v) {
215 OrderAccess::release_store(p, v);
216 }
218 inline void oopDesc::release_encode_store_heap_oop_not_null(
219 volatile narrowOop* p, oop v) {
220 // heap oop is not pointer sized.
221 OrderAccess::release_store(p, encode_heap_oop_not_null(v));
222 }
224 inline void oopDesc::release_encode_store_heap_oop_not_null(
225 volatile oop* p, oop v) {
226 OrderAccess::release_store_ptr(p, v);
227 }
229 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p,
230 oop v) {
231 OrderAccess::release_store_ptr(p, v);
232 }
233 inline void oopDesc::release_encode_store_heap_oop(
234 volatile narrowOop* p, oop v) {
235 OrderAccess::release_store(p, encode_heap_oop(v));
236 }
239 // These functions are only used to exchange oop fields in instances,
240 // not headers.
241 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) {
242 if (UseCompressedOops) {
243 // encode exchange value from oop to T
244 narrowOop val = encode_heap_oop(exchange_value);
245 narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest);
246 // decode old from T to oop
247 return decode_heap_oop(old);
248 } else {
249 return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest);
250 }
251 }
253 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value,
254 volatile HeapWord *dest,
255 oop compare_value) {
256 if (UseCompressedOops) {
257 // encode exchange and compare value from oop to T
258 narrowOop val = encode_heap_oop(exchange_value);
259 narrowOop cmp = encode_heap_oop(compare_value);
261 narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp);
262 // decode old from T to oop
263 return decode_heap_oop(old);
264 } else {
265 return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value);
266 }
267 }
269 // In order to put or get a field out of an instance, must first check
270 // if the field has been compressed and uncompress it.
271 inline oop oopDesc::obj_field(int offset) const {
272 return UseCompressedOops ?
273 load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) :
274 load_decode_heap_oop(obj_field_addr<oop>(offset));
275 }
276 inline void oopDesc::obj_field_put(int offset, oop value) {
277 UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) :
278 oop_store(obj_field_addr<oop>(offset), value);
279 }
280 inline void oopDesc::obj_field_raw_put(int offset, oop value) {
281 UseCompressedOops ?
282 encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) :
283 encode_store_heap_oop(obj_field_addr<oop>(offset), value);
284 }
286 inline jbyte oopDesc::byte_field(int offset) const { return (jbyte) *byte_field_addr(offset); }
287 inline void oopDesc::byte_field_put(int offset, jbyte contents) { *byte_field_addr(offset) = (jint) contents; }
289 inline jboolean oopDesc::bool_field(int offset) const { return (jboolean) *bool_field_addr(offset); }
290 inline void oopDesc::bool_field_put(int offset, jboolean contents) { *bool_field_addr(offset) = (jint) contents; }
292 inline jchar oopDesc::char_field(int offset) const { return (jchar) *char_field_addr(offset); }
293 inline void oopDesc::char_field_put(int offset, jchar contents) { *char_field_addr(offset) = (jint) contents; }
295 inline jint oopDesc::int_field(int offset) const { return *int_field_addr(offset); }
296 inline void oopDesc::int_field_put(int offset, jint contents) { *int_field_addr(offset) = contents; }
298 inline jshort oopDesc::short_field(int offset) const { return (jshort) *short_field_addr(offset); }
299 inline void oopDesc::short_field_put(int offset, jshort contents) { *short_field_addr(offset) = (jint) contents;}
301 inline jlong oopDesc::long_field(int offset) const { return *long_field_addr(offset); }
302 inline void oopDesc::long_field_put(int offset, jlong contents) { *long_field_addr(offset) = contents; }
304 inline jfloat oopDesc::float_field(int offset) const { return *float_field_addr(offset); }
305 inline void oopDesc::float_field_put(int offset, jfloat contents) { *float_field_addr(offset) = contents; }
307 inline jdouble oopDesc::double_field(int offset) const { return *double_field_addr(offset); }
308 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; }
310 inline address oopDesc::address_field(int offset) const { return *address_field_addr(offset); }
311 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; }
313 inline oop oopDesc::obj_field_acquire(int offset) const {
314 return UseCompressedOops ?
315 decode_heap_oop((narrowOop)
316 OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset)))
317 : decode_heap_oop((oop)
318 OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset)));
319 }
320 inline void oopDesc::release_obj_field_put(int offset, oop value) {
321 UseCompressedOops ?
322 oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) :
323 oop_store((volatile oop*) obj_field_addr<oop>(offset), value);
324 }
326 inline jbyte oopDesc::byte_field_acquire(int offset) const { return OrderAccess::load_acquire(byte_field_addr(offset)); }
327 inline void oopDesc::release_byte_field_put(int offset, jbyte contents) { OrderAccess::release_store(byte_field_addr(offset), contents); }
329 inline jboolean oopDesc::bool_field_acquire(int offset) const { return OrderAccess::load_acquire(bool_field_addr(offset)); }
330 inline void oopDesc::release_bool_field_put(int offset, jboolean contents) { OrderAccess::release_store(bool_field_addr(offset), contents); }
332 inline jchar oopDesc::char_field_acquire(int offset) const { return OrderAccess::load_acquire(char_field_addr(offset)); }
333 inline void oopDesc::release_char_field_put(int offset, jchar contents) { OrderAccess::release_store(char_field_addr(offset), contents); }
335 inline jint oopDesc::int_field_acquire(int offset) const { return OrderAccess::load_acquire(int_field_addr(offset)); }
336 inline void oopDesc::release_int_field_put(int offset, jint contents) { OrderAccess::release_store(int_field_addr(offset), contents); }
338 inline jshort oopDesc::short_field_acquire(int offset) const { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); }
339 inline void oopDesc::release_short_field_put(int offset, jshort contents) { OrderAccess::release_store(short_field_addr(offset), contents); }
341 inline jlong oopDesc::long_field_acquire(int offset) const { return OrderAccess::load_acquire(long_field_addr(offset)); }
342 inline void oopDesc::release_long_field_put(int offset, jlong contents) { OrderAccess::release_store(long_field_addr(offset), contents); }
344 inline jfloat oopDesc::float_field_acquire(int offset) const { return OrderAccess::load_acquire(float_field_addr(offset)); }
345 inline void oopDesc::release_float_field_put(int offset, jfloat contents) { OrderAccess::release_store(float_field_addr(offset), contents); }
347 inline jdouble oopDesc::double_field_acquire(int offset) const { return OrderAccess::load_acquire(double_field_addr(offset)); }
348 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); }
350 inline int oopDesc::size_given_klass(Klass* klass) {
351 int lh = klass->layout_helper();
352 int s = lh >> LogHeapWordSize; // deliver size scaled by wordSize
354 // lh is now a value computed at class initialization that may hint
355 // at the size. For instances, this is positive and equal to the
356 // size. For arrays, this is negative and provides log2 of the
357 // array element size. For other oops, it is zero and thus requires
358 // a virtual call.
359 //
360 // We go to all this trouble because the size computation is at the
361 // heart of phase 2 of mark-compaction, and called for every object,
362 // alive or dead. So the speed here is equal in importance to the
363 // speed of allocation.
365 if (lh <= Klass::_lh_neutral_value) {
366 // The most common case is instances; fall through if so.
367 if (lh < Klass::_lh_neutral_value) {
368 // Second most common case is arrays. We have to fetch the
369 // length of the array, shift (multiply) it appropriately,
370 // up to wordSize, add the header, and align to object size.
371 size_t size_in_bytes;
372 #ifdef _M_IA64
373 // The Windows Itanium Aug 2002 SDK hoists this load above
374 // the check for s < 0. An oop at the end of the heap will
375 // cause an access violation if this load is performed on a non
376 // array oop. Making the reference volatile prohibits this.
377 // (%%% please explain by what magic the length is actually fetched!)
378 volatile int *array_length;
379 array_length = (volatile int *)( (intptr_t)this +
380 arrayOopDesc::length_offset_in_bytes() );
381 assert(array_length > 0, "Integer arithmetic problem somewhere");
382 // Put into size_t to avoid overflow.
383 size_in_bytes = (size_t) array_length;
384 size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh);
385 #else
386 size_t array_length = (size_t) ((arrayOop)this)->length();
387 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh);
388 #endif
389 size_in_bytes += Klass::layout_helper_header_size(lh);
391 // This code could be simplified, but by keeping array_header_in_bytes
392 // in units of bytes and doing it this way we can round up just once,
393 // skipping the intermediate round to HeapWordSize. Cast the result
394 // of round_to to size_t to guarantee unsigned division == right shift.
395 s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) /
396 HeapWordSize);
398 // UseParNewGC can change the length field of an "old copy" of an object
399 // array in the young gen so it indicates the stealable portion of
400 // an already copied array. This will cause the first disjunct below
401 // to fail if the sizes are computed across such a concurrent change.
402 // UseParNewGC also runs with promotion labs (which look like int
403 // filler arrays) which are subject to changing their declared size
404 // when finally retiring a PLAB; this also can cause the first disjunct
405 // to fail for another worker thread that is concurrently walking the block
406 // offset table. Both these invariant failures are benign for their
407 // current uses; we relax the assertion checking to cover these two cases below:
408 // is_objArray() && is_forwarded() // covers first scenario above
409 // || is_typeArray() // covers second scenario above
410 // If and when UseParallelGC uses the same obj array oop stealing/chunking
411 // technique, or when G1 is integrated (and currently uses this array chunking
412 // technique) we will need to suitably modify the assertion.
413 assert((s == klass->oop_size(this)) ||
414 (((UseParNewGC || UseParallelGC) &&
415 Universe::heap()->is_gc_active()) &&
416 (is_typeArray() ||
417 (is_objArray() && is_forwarded()))),
418 "wrong array object size");
419 } else {
420 // Must be zero, so bite the bullet and take the virtual call.
421 s = klass->oop_size(this);
422 }
423 }
425 assert(s % MinObjAlignment == 0, "alignment check");
426 assert(s > 0, "Bad size calculated");
427 return s;
428 }
431 inline int oopDesc::size() {
432 return size_given_klass(blueprint());
433 }
435 inline bool oopDesc::is_parsable() {
436 return blueprint()->oop_is_parsable(this);
437 }
439 inline void update_barrier_set(void* p, oop v) {
440 assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!");
441 oopDesc::bs()->write_ref_field(p, v);
442 }
444 template <class T> inline void oop_store(T* p, oop v) {
445 if (always_do_update_barrier) {
446 oop_store((volatile T*)p, v);
447 } else {
448 oopDesc::encode_store_heap_oop(p, v);
449 update_barrier_set(p, v);
450 }
451 }
453 template <class T> inline void oop_store(volatile T* p, oop v) {
454 // Used by release_obj_field_put, so use release_store_ptr.
455 oopDesc::release_encode_store_heap_oop(p, v);
456 update_barrier_set((void*)p, v);
457 }
459 template <class T> inline void oop_store_without_check(T* p, oop v) {
460 // XXX YSR FIX ME!!!
461 if (always_do_update_barrier) {
462 oop_store(p, v);
463 } else {
464 assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier(p, v),
465 "oop store without store check failed");
466 oopDesc::encode_store_heap_oop(p, v);
467 }
468 }
470 // When it absolutely has to get there.
471 template <class T> inline void oop_store_without_check(volatile T* p, oop v) {
472 // XXX YSR FIX ME!!!
473 if (always_do_update_barrier) {
474 oop_store(p, v);
475 } else {
476 assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier((T*)p, v),
477 "oop store without store check failed");
478 oopDesc::release_encode_store_heap_oop(p, v);
479 }
480 }
482 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops
483 // (without having to remember the function name this calls).
484 inline void oop_store_raw(HeapWord* addr, oop value) {
485 if (UseCompressedOops) {
486 oopDesc::encode_store_heap_oop((narrowOop*)addr, value);
487 } else {
488 oopDesc::encode_store_heap_oop((oop*)addr, value);
489 }
490 }
492 // Used only for markSweep, scavenging
493 inline bool oopDesc::is_gc_marked() const {
494 return mark()->is_marked();
495 }
497 inline bool oopDesc::is_locked() const {
498 return mark()->is_locked();
499 }
501 inline bool oopDesc::is_unlocked() const {
502 return mark()->is_unlocked();
503 }
505 inline bool oopDesc::has_bias_pattern() const {
506 return mark()->has_bias_pattern();
507 }
509 inline bool check_obj_alignment(oop obj) {
510 return (intptr_t)obj % MinObjAlignmentInBytes == 0;
511 }
514 // used only for asserts
515 inline bool oopDesc::is_oop(bool ignore_mark_word) const {
516 oop obj = (oop) this;
517 if (!check_obj_alignment(obj)) return false;
518 if (!Universe::heap()->is_in_reserved(obj)) return false;
519 // obj is aligned and accessible in heap
520 // try to find metaclass cycle safely without seg faulting on bad input
521 // we should reach klassKlassObj by following klass link at most 3 times
522 for (int i = 0; i < 3; i++) {
523 obj = obj->klass_or_null();
524 // klass should be aligned and in permspace
525 if (!check_obj_alignment(obj)) return false;
526 if (!Universe::heap()->is_in_permanent(obj)) return false;
527 }
528 if (obj != Universe::klassKlassObj()) {
529 // During a dump, the _klassKlassObj moved to a shared space.
530 if (DumpSharedSpaces && Universe::klassKlassObj()->is_shared()) {
531 return true;
532 }
533 return false;
534 }
536 // Header verification: the mark is typically non-NULL. If we're
537 // at a safepoint, it must not be null.
538 // Outside of a safepoint, the header could be changing (for example,
539 // another thread could be inflating a lock on this object).
540 if (ignore_mark_word) {
541 return true;
542 }
543 if (mark() != NULL) {
544 return true;
545 }
546 return !SafepointSynchronize::is_at_safepoint();
547 }
550 // used only for asserts
551 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const {
552 return this == NULL ? true : is_oop(ignore_mark_word);
553 }
555 #ifndef PRODUCT
556 // used only for asserts
557 inline bool oopDesc::is_unlocked_oop() const {
558 if (!Universe::heap()->is_in_reserved(this)) return false;
559 return mark()->is_unlocked();
560 }
561 #endif // PRODUCT
563 inline void oopDesc::follow_header() {
564 if (UseCompressedOops) {
565 MarkSweep::mark_and_push(compressed_klass_addr());
566 } else {
567 MarkSweep::mark_and_push(klass_addr());
568 }
569 }
571 inline void oopDesc::follow_contents(void) {
572 assert (is_gc_marked(), "should be marked");
573 blueprint()->oop_follow_contents(this);
574 }
577 // Used by scavengers
579 inline bool oopDesc::is_forwarded() const {
580 // The extra heap check is needed since the obj might be locked, in which case the
581 // mark would point to a stack location and have the sentinel bit cleared
582 return mark()->is_marked();
583 }
585 // Used by scavengers
586 inline void oopDesc::forward_to(oop p) {
587 assert(Universe::heap()->is_in_reserved(p),
588 "forwarding to something not in heap");
589 markOop m = markOopDesc::encode_pointer_as_mark(p);
590 assert(m->decode_pointer() == p, "encoding must be reversable");
591 set_mark(m);
592 }
594 // Used by parallel scavengers
595 inline bool oopDesc::cas_forward_to(oop p, markOop compare) {
596 assert(Universe::heap()->is_in_reserved(p),
597 "forwarding to something not in heap");
598 markOop m = markOopDesc::encode_pointer_as_mark(p);
599 assert(m->decode_pointer() == p, "encoding must be reversable");
600 return cas_set_mark(m, compare) == compare;
601 }
603 // Note that the forwardee is not the same thing as the displaced_mark.
604 // The forwardee is used when copying during scavenge and mark-sweep.
605 // It does need to clear the low two locking- and GC-related bits.
606 inline oop oopDesc::forwardee() const {
607 return (oop) mark()->decode_pointer();
608 }
610 inline bool oopDesc::has_displaced_mark() const {
611 return mark()->has_displaced_mark_helper();
612 }
614 inline markOop oopDesc::displaced_mark() const {
615 return mark()->displaced_mark_helper();
616 }
618 inline void oopDesc::set_displaced_mark(markOop m) {
619 mark()->set_displaced_mark_helper(m);
620 }
622 // The following method needs to be MT safe.
623 inline int oopDesc::age() const {
624 assert(!is_forwarded(), "Attempt to read age from forwarded mark");
625 if (has_displaced_mark()) {
626 return displaced_mark()->age();
627 } else {
628 return mark()->age();
629 }
630 }
632 inline void oopDesc::incr_age() {
633 assert(!is_forwarded(), "Attempt to increment age of forwarded mark");
634 if (has_displaced_mark()) {
635 set_displaced_mark(displaced_mark()->incr_age());
636 } else {
637 set_mark(mark()->incr_age());
638 }
639 }
642 inline intptr_t oopDesc::identity_hash() {
643 // Fast case; if the object is unlocked and the hash value is set, no locking is needed
644 // Note: The mark must be read into local variable to avoid concurrent updates.
645 markOop mrk = mark();
646 if (mrk->is_unlocked() && !mrk->has_no_hash()) {
647 return mrk->hash();
648 } else if (mrk->is_marked()) {
649 return mrk->hash();
650 } else {
651 return slow_identity_hash();
652 }
653 }
655 inline void oopDesc::oop_iterate_header(OopClosure* blk) {
656 if (UseCompressedOops) {
657 blk->do_oop(compressed_klass_addr());
658 } else {
659 blk->do_oop(klass_addr());
660 }
661 }
663 inline void oopDesc::oop_iterate_header(OopClosure* blk, MemRegion mr) {
664 if (UseCompressedOops) {
665 if (mr.contains(compressed_klass_addr())) {
666 blk->do_oop(compressed_klass_addr());
667 }
668 } else {
669 if (mr.contains(klass_addr())) blk->do_oop(klass_addr());
670 }
671 }
673 inline int oopDesc::adjust_pointers() {
674 debug_only(int check_size = size());
675 int s = blueprint()->oop_adjust_pointers(this);
676 assert(s == check_size, "should be the same");
677 return s;
678 }
680 inline void oopDesc::adjust_header() {
681 if (UseCompressedOops) {
682 MarkSweep::adjust_pointer(compressed_klass_addr());
683 } else {
684 MarkSweep::adjust_pointer(klass_addr());
685 }
686 }
688 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \
689 \
690 inline int oopDesc::oop_iterate(OopClosureType* blk) { \
691 SpecializationStats::record_call(); \
692 return blueprint()->oop_oop_iterate##nv_suffix(this, blk); \
693 } \
694 \
695 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \
696 SpecializationStats::record_call(); \
697 return blueprint()->oop_oop_iterate##nv_suffix##_m(this, blk, mr); \
698 }
700 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN)
701 ALL_OOP_OOP_ITERATE_CLOSURES_3(OOP_ITERATE_DEFN)
704 inline bool oopDesc::is_shared() const {
705 return CompactingPermGenGen::is_shared(this);
706 }
708 inline bool oopDesc::is_shared_readonly() const {
709 return CompactingPermGenGen::is_shared_readonly(this);
710 }
712 inline bool oopDesc::is_shared_readwrite() const {
713 return CompactingPermGenGen::is_shared_readwrite(this);
714 }