oop.inline.hpp revision 1472:c18cbe5936b8
1/* 2 * Copyright (c) 1997, 2009, 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// Implementation of all inlined member functions defined in oop.hpp 26// We need a separate file to avoid circular references 27 28inline void oopDesc::release_set_mark(markOop m) { 29 OrderAccess::release_store_ptr(&_mark, m); 30} 31 32inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) { 33 return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark); 34} 35 36inline 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} 43 44inline 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} 52 53inline 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} 57 58inline 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} 64 65inline narrowOop* oopDesc::compressed_klass_addr() { 66 assert(UseCompressedOops, "only called by compressed oops"); 67 return (narrowOop*) &_metadata._compressed_klass; 68} 69 70inline 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} 80 81inline int oopDesc::klass_gap() const { 82 return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()); 83} 84 85inline void oopDesc::set_klass_gap(int v) { 86 if (UseCompressedOops) { 87 *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v; 88 } 89} 90 91inline 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(k); // may be null (parnew overflow handling) 96 } else { 97 _metadata._klass = (klassOop)k; 98 } 99} 100 101inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); } 102inline Klass* oopDesc::blueprint() const { return klass()->klass_part(); } 103 104inline bool oopDesc::is_a(klassOop k) const { return blueprint()->is_subtype_of(k); } 105 106inline bool oopDesc::is_instance() const { return blueprint()->oop_is_instance(); } 107inline bool oopDesc::is_instanceRef() const { return blueprint()->oop_is_instanceRef(); } 108inline bool oopDesc::is_array() const { return blueprint()->oop_is_array(); } 109inline bool oopDesc::is_objArray() const { return blueprint()->oop_is_objArray(); } 110inline bool oopDesc::is_typeArray() const { return blueprint()->oop_is_typeArray(); } 111inline bool oopDesc::is_javaArray() const { return blueprint()->oop_is_javaArray(); } 112inline bool oopDesc::is_symbol() const { return blueprint()->oop_is_symbol(); } 113inline bool oopDesc::is_klass() const { return blueprint()->oop_is_klass(); } 114inline bool oopDesc::is_thread() const { return blueprint()->oop_is_thread(); } 115inline bool oopDesc::is_method() const { return blueprint()->oop_is_method(); } 116inline bool oopDesc::is_constMethod() const { return blueprint()->oop_is_constMethod(); } 117inline bool oopDesc::is_methodData() const { return blueprint()->oop_is_methodData(); } 118inline bool oopDesc::is_constantPool() const { return blueprint()->oop_is_constantPool(); } 119inline bool oopDesc::is_constantPoolCache() const { return blueprint()->oop_is_constantPoolCache(); } 120inline bool oopDesc::is_compiledICHolder() const { return blueprint()->oop_is_compiledICHolder(); } 121 122inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; } 123 124template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); } 125inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); } 126inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); } 127inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); } 128inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); } 129inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); } 130inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); } 131inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); } 132inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); } 133inline address* oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); } 134 135 136// 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). 141 142inline bool oopDesc::is_null(oop obj) { return obj == NULL; } 143inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; } 144 145// 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. 148 149inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) { 150 assert(!is_null(v), "oop value can never be zero"); 151 assert(Universe::heap()->is_in_reserved(v), "Address not in heap"); 152 address base = Universe::narrow_oop_base(); 153 int shift = Universe::narrow_oop_shift(); 154 uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1)); 155 assert(OopEncodingHeapMax > pd, "change encoding max if new encoding"); 156 uint64_t result = pd >> shift; 157 assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow"); 158 assert(decode_heap_oop(result) == v, "reversibility"); 159 return (narrowOop)result; 160} 161 162inline narrowOop oopDesc::encode_heap_oop(oop v) { 163 return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v); 164} 165 166inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) { 167 assert(!is_null(v), "narrow oop value can never be zero"); 168 address base = Universe::narrow_oop_base(); 169 int shift = Universe::narrow_oop_shift(); 170 return (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift)); 171} 172 173inline oop oopDesc::decode_heap_oop(narrowOop v) { 174 return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v); 175} 176 177inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; } 178inline oop oopDesc::decode_heap_oop(oop v) { return v; } 179 180// Load an oop out of the Java heap as is without decoding. 181// Called by GC to check for null before decoding. 182inline oop oopDesc::load_heap_oop(oop* p) { return *p; } 183inline narrowOop oopDesc::load_heap_oop(narrowOop* p) { return *p; } 184 185// Load and decode an oop out of the Java heap into a wide oop. 186inline oop oopDesc::load_decode_heap_oop_not_null(oop* p) { return *p; } 187inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) { 188 return decode_heap_oop_not_null(*p); 189} 190 191// Load and decode an oop out of the heap accepting null 192inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; } 193inline oop oopDesc::load_decode_heap_oop(narrowOop* p) { 194 return decode_heap_oop(*p); 195} 196 197// Store already encoded heap oop into the heap. 198inline void oopDesc::store_heap_oop(oop* p, oop v) { *p = v; } 199inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v) { *p = v; } 200 201// Encode and store a heap oop. 202inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) { 203 *p = encode_heap_oop_not_null(v); 204} 205inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; } 206 207// Encode and store a heap oop allowing for null. 208inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) { 209 *p = encode_heap_oop(v); 210} 211inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; } 212 213// Store heap oop as is for volatile fields. 214inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) { 215 OrderAccess::release_store_ptr(p, v); 216} 217inline void oopDesc::release_store_heap_oop(volatile narrowOop* p, 218 narrowOop v) { 219 OrderAccess::release_store(p, v); 220} 221 222inline void oopDesc::release_encode_store_heap_oop_not_null( 223 volatile narrowOop* p, oop v) { 224 // heap oop is not pointer sized. 225 OrderAccess::release_store(p, encode_heap_oop_not_null(v)); 226} 227 228inline void oopDesc::release_encode_store_heap_oop_not_null( 229 volatile oop* p, oop v) { 230 OrderAccess::release_store_ptr(p, v); 231} 232 233inline void oopDesc::release_encode_store_heap_oop(volatile oop* p, 234 oop v) { 235 OrderAccess::release_store_ptr(p, v); 236} 237inline void oopDesc::release_encode_store_heap_oop( 238 volatile narrowOop* p, oop v) { 239 OrderAccess::release_store(p, encode_heap_oop(v)); 240} 241 242 243// These functions are only used to exchange oop fields in instances, 244// not headers. 245inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) { 246 if (UseCompressedOops) { 247 // encode exchange value from oop to T 248 narrowOop val = encode_heap_oop(exchange_value); 249 narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest); 250 // decode old from T to oop 251 return decode_heap_oop(old); 252 } else { 253 return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest); 254 } 255} 256 257inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value, 258 volatile HeapWord *dest, 259 oop compare_value) { 260 if (UseCompressedOops) { 261 // encode exchange and compare value from oop to T 262 narrowOop val = encode_heap_oop(exchange_value); 263 narrowOop cmp = encode_heap_oop(compare_value); 264 265 narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp); 266 // decode old from T to oop 267 return decode_heap_oop(old); 268 } else { 269 return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value); 270 } 271} 272 273// In order to put or get a field out of an instance, must first check 274// if the field has been compressed and uncompress it. 275inline oop oopDesc::obj_field(int offset) const { 276 return UseCompressedOops ? 277 load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) : 278 load_decode_heap_oop(obj_field_addr<oop>(offset)); 279} 280inline void oopDesc::obj_field_put(int offset, oop value) { 281 UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) : 282 oop_store(obj_field_addr<oop>(offset), value); 283} 284inline void oopDesc::obj_field_raw_put(int offset, oop value) { 285 UseCompressedOops ? 286 encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) : 287 encode_store_heap_oop(obj_field_addr<oop>(offset), value); 288} 289 290inline jbyte oopDesc::byte_field(int offset) const { return (jbyte) *byte_field_addr(offset); } 291inline void oopDesc::byte_field_put(int offset, jbyte contents) { *byte_field_addr(offset) = (jint) contents; } 292 293inline jboolean oopDesc::bool_field(int offset) const { return (jboolean) *bool_field_addr(offset); } 294inline void oopDesc::bool_field_put(int offset, jboolean contents) { *bool_field_addr(offset) = (jint) contents; } 295 296inline jchar oopDesc::char_field(int offset) const { return (jchar) *char_field_addr(offset); } 297inline void oopDesc::char_field_put(int offset, jchar contents) { *char_field_addr(offset) = (jint) contents; } 298 299inline jint oopDesc::int_field(int offset) const { return *int_field_addr(offset); } 300inline void oopDesc::int_field_put(int offset, jint contents) { *int_field_addr(offset) = contents; } 301 302inline jshort oopDesc::short_field(int offset) const { return (jshort) *short_field_addr(offset); } 303inline void oopDesc::short_field_put(int offset, jshort contents) { *short_field_addr(offset) = (jint) contents;} 304 305inline jlong oopDesc::long_field(int offset) const { return *long_field_addr(offset); } 306inline void oopDesc::long_field_put(int offset, jlong contents) { *long_field_addr(offset) = contents; } 307 308inline jfloat oopDesc::float_field(int offset) const { return *float_field_addr(offset); } 309inline void oopDesc::float_field_put(int offset, jfloat contents) { *float_field_addr(offset) = contents; } 310 311inline jdouble oopDesc::double_field(int offset) const { return *double_field_addr(offset); } 312inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; } 313 314inline address oopDesc::address_field(int offset) const { return *address_field_addr(offset); } 315inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; } 316 317inline oop oopDesc::obj_field_acquire(int offset) const { 318 return UseCompressedOops ? 319 decode_heap_oop((narrowOop) 320 OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset))) 321 : decode_heap_oop((oop) 322 OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset))); 323} 324inline void oopDesc::release_obj_field_put(int offset, oop value) { 325 UseCompressedOops ? 326 oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) : 327 oop_store((volatile oop*) obj_field_addr<oop>(offset), value); 328} 329 330inline jbyte oopDesc::byte_field_acquire(int offset) const { return OrderAccess::load_acquire(byte_field_addr(offset)); } 331inline void oopDesc::release_byte_field_put(int offset, jbyte contents) { OrderAccess::release_store(byte_field_addr(offset), contents); } 332 333inline jboolean oopDesc::bool_field_acquire(int offset) const { return OrderAccess::load_acquire(bool_field_addr(offset)); } 334inline void oopDesc::release_bool_field_put(int offset, jboolean contents) { OrderAccess::release_store(bool_field_addr(offset), contents); } 335 336inline jchar oopDesc::char_field_acquire(int offset) const { return OrderAccess::load_acquire(char_field_addr(offset)); } 337inline void oopDesc::release_char_field_put(int offset, jchar contents) { OrderAccess::release_store(char_field_addr(offset), contents); } 338 339inline jint oopDesc::int_field_acquire(int offset) const { return OrderAccess::load_acquire(int_field_addr(offset)); } 340inline void oopDesc::release_int_field_put(int offset, jint contents) { OrderAccess::release_store(int_field_addr(offset), contents); } 341 342inline jshort oopDesc::short_field_acquire(int offset) const { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); } 343inline void oopDesc::release_short_field_put(int offset, jshort contents) { OrderAccess::release_store(short_field_addr(offset), contents); } 344 345inline jlong oopDesc::long_field_acquire(int offset) const { return OrderAccess::load_acquire(long_field_addr(offset)); } 346inline void oopDesc::release_long_field_put(int offset, jlong contents) { OrderAccess::release_store(long_field_addr(offset), contents); } 347 348inline jfloat oopDesc::float_field_acquire(int offset) const { return OrderAccess::load_acquire(float_field_addr(offset)); } 349inline void oopDesc::release_float_field_put(int offset, jfloat contents) { OrderAccess::release_store(float_field_addr(offset), contents); } 350 351inline jdouble oopDesc::double_field_acquire(int offset) const { return OrderAccess::load_acquire(double_field_addr(offset)); } 352inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); } 353 354inline address oopDesc::address_field_acquire(int offset) const { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); } 355inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); } 356 357inline int oopDesc::size_given_klass(Klass* klass) { 358 int lh = klass->layout_helper(); 359 int s = lh >> LogHeapWordSize; // deliver size scaled by wordSize 360 361 // lh is now a value computed at class initialization that may hint 362 // at the size. For instances, this is positive and equal to the 363 // size. For arrays, this is negative and provides log2 of the 364 // array element size. For other oops, it is zero and thus requires 365 // a virtual call. 366 // 367 // We go to all this trouble because the size computation is at the 368 // heart of phase 2 of mark-compaction, and called for every object, 369 // alive or dead. So the speed here is equal in importance to the 370 // speed of allocation. 371 372 if (lh <= Klass::_lh_neutral_value) { 373 // The most common case is instances; fall through if so. 374 if (lh < Klass::_lh_neutral_value) { 375 // Second most common case is arrays. We have to fetch the 376 // length of the array, shift (multiply) it appropriately, 377 // up to wordSize, add the header, and align to object size. 378 size_t size_in_bytes; 379#ifdef _M_IA64 380 // The Windows Itanium Aug 2002 SDK hoists this load above 381 // the check for s < 0. An oop at the end of the heap will 382 // cause an access violation if this load is performed on a non 383 // array oop. Making the reference volatile prohibits this. 384 // (%%% please explain by what magic the length is actually fetched!) 385 volatile int *array_length; 386 array_length = (volatile int *)( (intptr_t)this + 387 arrayOopDesc::length_offset_in_bytes() ); 388 assert(array_length > 0, "Integer arithmetic problem somewhere"); 389 // Put into size_t to avoid overflow. 390 size_in_bytes = (size_t) array_length; 391 size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh); 392#else 393 size_t array_length = (size_t) ((arrayOop)this)->length(); 394 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh); 395#endif 396 size_in_bytes += Klass::layout_helper_header_size(lh); 397 398 // This code could be simplified, but by keeping array_header_in_bytes 399 // in units of bytes and doing it this way we can round up just once, 400 // skipping the intermediate round to HeapWordSize. Cast the result 401 // of round_to to size_t to guarantee unsigned division == right shift. 402 s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) / 403 HeapWordSize); 404 405 // UseParNewGC, UseParallelGC and UseG1GC can change the length field 406 // of an "old copy" of an object array in the young gen so it indicates 407 // the grey portion of an already copied array. This will cause the first 408 // disjunct below to fail if the two comparands are computed across such 409 // a concurrent change. 410 // UseParNewGC also runs with promotion labs (which look like int 411 // filler arrays) which are subject to changing their declared size 412 // when finally retiring a PLAB; this also can cause the first disjunct 413 // to fail for another worker thread that is concurrently walking the block 414 // offset table. Both these invariant failures are benign for their 415 // current uses; we relax the assertion checking to cover these two cases below: 416 // is_objArray() && is_forwarded() // covers first scenario above 417 // || is_typeArray() // covers second scenario above 418 // If and when UseParallelGC uses the same obj array oop stealing/chunking 419 // technique, we will need to suitably modify the assertion. 420 assert((s == klass->oop_size(this)) || 421 (Universe::heap()->is_gc_active() && 422 ((is_typeArray() && UseParNewGC) || 423 (is_objArray() && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))), 424 "wrong array object size"); 425 } else { 426 // Must be zero, so bite the bullet and take the virtual call. 427 s = klass->oop_size(this); 428 } 429 } 430 431 assert(s % MinObjAlignment == 0, "alignment check"); 432 assert(s > 0, "Bad size calculated"); 433 return s; 434} 435 436 437inline int oopDesc::size() { 438 return size_given_klass(blueprint()); 439} 440 441inline bool oopDesc::is_parsable() { 442 return blueprint()->oop_is_parsable(this); 443} 444 445inline bool oopDesc::is_conc_safe() { 446 return blueprint()->oop_is_conc_safe(this); 447} 448 449inline void update_barrier_set(void* p, oop v) { 450 assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!"); 451 oopDesc::bs()->write_ref_field(p, v); 452} 453 454template <class T> inline void update_barrier_set_pre(T* p, oop v) { 455 oopDesc::bs()->write_ref_field_pre(p, v); 456} 457 458template <class T> inline void oop_store(T* p, oop v) { 459 if (always_do_update_barrier) { 460 oop_store((volatile T*)p, v); 461 } else { 462 update_barrier_set_pre(p, v); 463 oopDesc::encode_store_heap_oop(p, v); 464 update_barrier_set((void*)p, v); // cast away type 465 } 466} 467 468template <class T> inline void oop_store(volatile T* p, oop v) { 469 update_barrier_set_pre((T*)p, v); // cast away volatile 470 // Used by release_obj_field_put, so use release_store_ptr. 471 oopDesc::release_encode_store_heap_oop(p, v); 472 update_barrier_set((void*)p, v); // cast away type 473} 474 475template <class T> inline void oop_store_without_check(T* p, oop v) { 476 // XXX YSR FIX ME!!! 477 if (always_do_update_barrier) { 478 oop_store(p, v); 479 } else { 480 assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier(p, v), 481 "oop store without store check failed"); 482 oopDesc::encode_store_heap_oop(p, v); 483 } 484} 485 486// When it absolutely has to get there. 487template <class T> inline void oop_store_without_check(volatile T* p, oop v) { 488 // XXX YSR FIX ME!!! 489 if (always_do_update_barrier) { 490 oop_store(p, v); 491 } else { 492 assert(!Universe::heap()->barrier_set()->write_ref_needs_barrier((T*)p, v), 493 "oop store without store check failed"); 494 oopDesc::release_encode_store_heap_oop(p, v); 495 } 496} 497 498// Should replace *addr = oop assignments where addr type depends on UseCompressedOops 499// (without having to remember the function name this calls). 500inline void oop_store_raw(HeapWord* addr, oop value) { 501 if (UseCompressedOops) { 502 oopDesc::encode_store_heap_oop((narrowOop*)addr, value); 503 } else { 504 oopDesc::encode_store_heap_oop((oop*)addr, value); 505 } 506} 507 508// Used only for markSweep, scavenging 509inline bool oopDesc::is_gc_marked() const { 510 return mark()->is_marked(); 511} 512 513inline bool oopDesc::is_locked() const { 514 return mark()->is_locked(); 515} 516 517inline bool oopDesc::is_unlocked() const { 518 return mark()->is_unlocked(); 519} 520 521inline bool oopDesc::has_bias_pattern() const { 522 return mark()->has_bias_pattern(); 523} 524 525inline bool check_obj_alignment(oop obj) { 526 return (intptr_t)obj % MinObjAlignmentInBytes == 0; 527} 528 529 530// used only for asserts 531inline bool oopDesc::is_oop(bool ignore_mark_word) const { 532 oop obj = (oop) this; 533 if (!check_obj_alignment(obj)) return false; 534 if (!Universe::heap()->is_in_reserved(obj)) return false; 535 // obj is aligned and accessible in heap 536 // try to find metaclass cycle safely without seg faulting on bad input 537 // we should reach klassKlassObj by following klass link at most 3 times 538 for (int i = 0; i < 3; i++) { 539 obj = obj->klass_or_null(); 540 // klass should be aligned and in permspace 541 if (!check_obj_alignment(obj)) return false; 542 if (!Universe::heap()->is_in_permanent(obj)) return false; 543 } 544 if (obj != Universe::klassKlassObj()) { 545 // During a dump, the _klassKlassObj moved to a shared space. 546 if (DumpSharedSpaces && Universe::klassKlassObj()->is_shared()) { 547 return true; 548 } 549 return false; 550 } 551 552 // Header verification: the mark is typically non-NULL. If we're 553 // at a safepoint, it must not be null. 554 // Outside of a safepoint, the header could be changing (for example, 555 // another thread could be inflating a lock on this object). 556 if (ignore_mark_word) { 557 return true; 558 } 559 if (mark() != NULL) { 560 return true; 561 } 562 return !SafepointSynchronize::is_at_safepoint(); 563} 564 565 566// used only for asserts 567inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const { 568 return this == NULL ? true : is_oop(ignore_mark_word); 569} 570 571#ifndef PRODUCT 572// used only for asserts 573inline bool oopDesc::is_unlocked_oop() const { 574 if (!Universe::heap()->is_in_reserved(this)) return false; 575 return mark()->is_unlocked(); 576} 577#endif // PRODUCT 578 579inline void oopDesc::follow_header() { 580 if (UseCompressedOops) { 581 MarkSweep::mark_and_push(compressed_klass_addr()); 582 } else { 583 MarkSweep::mark_and_push(klass_addr()); 584 } 585} 586 587inline void oopDesc::follow_contents(void) { 588 assert (is_gc_marked(), "should be marked"); 589 blueprint()->oop_follow_contents(this); 590} 591 592 593// Used by scavengers 594 595inline bool oopDesc::is_forwarded() const { 596 // The extra heap check is needed since the obj might be locked, in which case the 597 // mark would point to a stack location and have the sentinel bit cleared 598 return mark()->is_marked(); 599} 600 601// Used by scavengers 602inline void oopDesc::forward_to(oop p) { 603 assert(Universe::heap()->is_in_reserved(p), 604 "forwarding to something not in heap"); 605 markOop m = markOopDesc::encode_pointer_as_mark(p); 606 assert(m->decode_pointer() == p, "encoding must be reversable"); 607 set_mark(m); 608} 609 610// Used by parallel scavengers 611inline bool oopDesc::cas_forward_to(oop p, markOop compare) { 612 assert(Universe::heap()->is_in_reserved(p), 613 "forwarding to something not in heap"); 614 markOop m = markOopDesc::encode_pointer_as_mark(p); 615 assert(m->decode_pointer() == p, "encoding must be reversable"); 616 return cas_set_mark(m, compare) == compare; 617} 618 619// Note that the forwardee is not the same thing as the displaced_mark. 620// The forwardee is used when copying during scavenge and mark-sweep. 621// It does need to clear the low two locking- and GC-related bits. 622inline oop oopDesc::forwardee() const { 623 return (oop) mark()->decode_pointer(); 624} 625 626inline bool oopDesc::has_displaced_mark() const { 627 return mark()->has_displaced_mark_helper(); 628} 629 630inline markOop oopDesc::displaced_mark() const { 631 return mark()->displaced_mark_helper(); 632} 633 634inline void oopDesc::set_displaced_mark(markOop m) { 635 mark()->set_displaced_mark_helper(m); 636} 637 638// The following method needs to be MT safe. 639inline int oopDesc::age() const { 640 assert(!is_forwarded(), "Attempt to read age from forwarded mark"); 641 if (has_displaced_mark()) { 642 return displaced_mark()->age(); 643 } else { 644 return mark()->age(); 645 } 646} 647 648inline void oopDesc::incr_age() { 649 assert(!is_forwarded(), "Attempt to increment age of forwarded mark"); 650 if (has_displaced_mark()) { 651 set_displaced_mark(displaced_mark()->incr_age()); 652 } else { 653 set_mark(mark()->incr_age()); 654 } 655} 656 657 658inline intptr_t oopDesc::identity_hash() { 659 // Fast case; if the object is unlocked and the hash value is set, no locking is needed 660 // Note: The mark must be read into local variable to avoid concurrent updates. 661 markOop mrk = mark(); 662 if (mrk->is_unlocked() && !mrk->has_no_hash()) { 663 return mrk->hash(); 664 } else if (mrk->is_marked()) { 665 return mrk->hash(); 666 } else { 667 return slow_identity_hash(); 668 } 669} 670 671inline void oopDesc::oop_iterate_header(OopClosure* blk) { 672 if (UseCompressedOops) { 673 blk->do_oop(compressed_klass_addr()); 674 } else { 675 blk->do_oop(klass_addr()); 676 } 677} 678 679inline void oopDesc::oop_iterate_header(OopClosure* blk, MemRegion mr) { 680 if (UseCompressedOops) { 681 if (mr.contains(compressed_klass_addr())) { 682 blk->do_oop(compressed_klass_addr()); 683 } 684 } else { 685 if (mr.contains(klass_addr())) blk->do_oop(klass_addr()); 686 } 687} 688 689inline int oopDesc::adjust_pointers() { 690 debug_only(int check_size = size()); 691 int s = blueprint()->oop_adjust_pointers(this); 692 assert(s == check_size, "should be the same"); 693 return s; 694} 695 696inline void oopDesc::adjust_header() { 697 if (UseCompressedOops) { 698 MarkSweep::adjust_pointer(compressed_klass_addr()); 699 } else { 700 MarkSweep::adjust_pointer(klass_addr()); 701 } 702} 703 704#define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \ 705 \ 706inline int oopDesc::oop_iterate(OopClosureType* blk) { \ 707 SpecializationStats::record_call(); \ 708 return blueprint()->oop_oop_iterate##nv_suffix(this, blk); \ 709} \ 710 \ 711inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \ 712 SpecializationStats::record_call(); \ 713 return blueprint()->oop_oop_iterate##nv_suffix##_m(this, blk, mr); \ 714} 715 716ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN) 717ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN) 718 719#ifndef SERIALGC 720#define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \ 721 \ 722inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) { \ 723 SpecializationStats::record_call(); \ 724 return blueprint()->oop_oop_iterate_backwards##nv_suffix(this, blk); \ 725} 726 727ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN) 728ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN) 729#endif // !SERIALGC 730 731inline bool oopDesc::is_shared() const { 732 return CompactingPermGenGen::is_shared(this); 733} 734 735inline bool oopDesc::is_shared_readonly() const { 736 return CompactingPermGenGen::is_shared_readonly(this); 737} 738 739inline bool oopDesc::is_shared_readwrite() const { 740 return CompactingPermGenGen::is_shared_readwrite(this); 741} 742