1 /* 2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_OOPS_OOP_INLINE_HPP 26 #define SHARE_VM_OOPS_OOP_INLINE_HPP 27 28 #include "gc_implementation/shared/ageTable.hpp" 29 #include "gc_implementation/shared/markSweep.inline.hpp" 30 #include "gc_interface/collectedHeap.inline.hpp" 31 #include "memory/barrierSet.inline.hpp" 32 #include "memory/cardTableModRefBS.hpp" 33 #include "memory/genCollectedHeap.hpp" 34 #include "memory/generation.hpp" 35 #include "memory/specialized_oop_closures.hpp" 36 #include "oops/arrayKlass.hpp" 37 #include "oops/arrayOop.hpp" 38 #include "oops/klass.inline.hpp" 39 #include "oops/markOop.inline.hpp" 40 #include "oops/oop.hpp" 41 #include "runtime/atomic.hpp" 42 #include "runtime/os.hpp" 43 #include "utilities/macros.hpp" 44 #ifdef TARGET_ARCH_x86 45 # include "bytes_x86.hpp" 46 #endif 47 #ifdef TARGET_ARCH_sparc 48 # include "bytes_sparc.hpp" 49 #endif 50 #ifdef TARGET_ARCH_zero 51 # include "bytes_zero.hpp" 52 #endif 53 #ifdef TARGET_ARCH_arm 54 # include "bytes_arm.hpp" 55 #endif 56 #ifdef TARGET_ARCH_ppc 57 # include "bytes_ppc.hpp" 58 #endif 59 60 // Implementation of all inlined member functions defined in oop.hpp 61 // We need a separate file to avoid circular references 62 63 inline void oopDesc::release_set_mark(markOop m) { 64 OrderAccess::release_store_ptr(&_mark, m); 65 } 66 67 inline markOop oopDesc::cas_set_mark(markOop new_mark, markOop old_mark) { 68 return (markOop) Atomic::cmpxchg_ptr(new_mark, &_mark, old_mark); 69 } 70 71 inline Klass* oopDesc::klass() const { 72 if (UseCompressedClassPointers) { 73 return Klass::decode_klass_not_null(_metadata._compressed_klass); 74 } else { 75 return _metadata._klass; 76 } 77 } 78 79 inline Klass* oopDesc::klass_or_null() const volatile { 80 // can be NULL in CMS 81 if (UseCompressedClassPointers) { 82 return Klass::decode_klass(_metadata._compressed_klass); 83 } else { 84 return _metadata._klass; 85 } 86 } 87 88 inline int oopDesc::klass_gap_offset_in_bytes() { 89 assert(UseCompressedClassPointers, "only applicable to compressed klass pointers"); 90 return oopDesc::klass_offset_in_bytes() + sizeof(narrowKlass); 91 } 92 93 inline Klass** oopDesc::klass_addr() { 94 // Only used internally and with CMS and will not work with 95 // UseCompressedOops 96 assert(!UseCompressedClassPointers, "only supported with uncompressed klass pointers"); 97 return (Klass**) &_metadata._klass; 98 } 99 100 inline narrowKlass* oopDesc::compressed_klass_addr() { 101 assert(UseCompressedClassPointers, "only called by compressed klass pointers"); 102 return &_metadata._compressed_klass; 103 } 104 105 inline void oopDesc::set_klass(Klass* k) { 106 // since klasses are promoted no store check is needed 107 assert(Universe::is_bootstrapping() || k != NULL, "must be a real Klass*"); 108 assert(Universe::is_bootstrapping() || k->is_klass(), "not a Klass*"); 109 if (UseCompressedClassPointers) { 110 *compressed_klass_addr() = Klass::encode_klass_not_null(k); 111 } else { 112 *klass_addr() = k; 113 } 114 } 115 116 inline int oopDesc::klass_gap() const { 117 return *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()); 118 } 119 120 inline void oopDesc::set_klass_gap(int v) { 121 if (UseCompressedClassPointers) { 122 *(int*)(((intptr_t)this) + klass_gap_offset_in_bytes()) = v; 123 } 124 } 125 126 inline void oopDesc::set_klass_to_list_ptr(oop k) { 127 // This is only to be used during GC, for from-space objects, so no 128 // barrier is needed. 129 if (UseCompressedClassPointers) { 130 _metadata._compressed_klass = (narrowKlass)encode_heap_oop(k); // may be null (parnew overflow handling) 131 } else { 132 _metadata._klass = (Klass*)(address)k; 133 } 134 } 135 136 inline oop oopDesc::list_ptr_from_klass() { 137 // This is only to be used during GC, for from-space objects. 138 if (UseCompressedClassPointers) { 139 return decode_heap_oop((narrowOop)_metadata._compressed_klass); 140 } else { 141 // Special case for GC 142 return (oop)(address)_metadata._klass; 143 } 144 } 145 146 inline void oopDesc::init_mark() { set_mark(markOopDesc::prototype_for_object(this)); } 147 148 inline bool oopDesc::is_a(Klass* k) const { return klass()->is_subtype_of(k); } 149 150 inline bool oopDesc::is_instance() const { return klass()->oop_is_instance(); } 151 inline bool oopDesc::is_instanceClassLoader() const { return klass()->oop_is_instanceClassLoader(); } 152 inline bool oopDesc::is_instanceMirror() const { return klass()->oop_is_instanceMirror(); } 153 inline bool oopDesc::is_instanceRef() const { return klass()->oop_is_instanceRef(); } 154 inline bool oopDesc::is_array() const { return klass()->oop_is_array(); } 155 inline bool oopDesc::is_objArray() const { return klass()->oop_is_objArray(); } 156 inline bool oopDesc::is_typeArray() const { return klass()->oop_is_typeArray(); } 157 158 inline void* oopDesc::field_base(int offset) const { return (void*)&((char*)this)[offset]; } 159 160 template <class T> inline T* oopDesc::obj_field_addr(int offset) const { return (T*)field_base(offset); } 161 inline Metadata** oopDesc::metadata_field_addr(int offset) const { return (Metadata**)field_base(offset); } 162 inline jbyte* oopDesc::byte_field_addr(int offset) const { return (jbyte*) field_base(offset); } 163 inline jchar* oopDesc::char_field_addr(int offset) const { return (jchar*) field_base(offset); } 164 inline jboolean* oopDesc::bool_field_addr(int offset) const { return (jboolean*)field_base(offset); } 165 inline jint* oopDesc::int_field_addr(int offset) const { return (jint*) field_base(offset); } 166 inline jshort* oopDesc::short_field_addr(int offset) const { return (jshort*) field_base(offset); } 167 inline jlong* oopDesc::long_field_addr(int offset) const { return (jlong*) field_base(offset); } 168 inline jfloat* oopDesc::float_field_addr(int offset) const { return (jfloat*) field_base(offset); } 169 inline jdouble* oopDesc::double_field_addr(int offset) const { return (jdouble*) field_base(offset); } 170 inline address* oopDesc::address_field_addr(int offset) const { return (address*) field_base(offset); } 171 172 173 // Functions for getting and setting oops within instance objects. 174 // If the oops are compressed, the type passed to these overloaded functions 175 // is narrowOop. All functions are overloaded so they can be called by 176 // template functions without conditionals (the compiler instantiates via 177 // the right type and inlines the appopriate code). 178 179 inline bool oopDesc::is_null(oop obj) { return obj == NULL; } 180 inline bool oopDesc::is_null(narrowOop obj) { return obj == 0; } 181 182 // Algorithm for encoding and decoding oops from 64 bit pointers to 32 bit 183 // offset from the heap base. Saving the check for null can save instructions 184 // in inner GC loops so these are separated. 185 186 inline bool check_obj_alignment(oop obj) { 187 return cast_from_oop<intptr_t>(obj) % MinObjAlignmentInBytes == 0; 188 } 189 190 inline narrowOop oopDesc::encode_heap_oop_not_null(oop v) { 191 assert(!is_null(v), "oop value can never be zero"); 192 assert(check_obj_alignment(v), "Address not aligned"); 193 assert(Universe::heap()->is_in_reserved(v), "Address not in heap"); 194 address base = Universe::narrow_oop_base(); 195 int shift = Universe::narrow_oop_shift(); 196 uint64_t pd = (uint64_t)(pointer_delta((void*)v, (void*)base, 1)); 197 assert(OopEncodingHeapMax > pd, "change encoding max if new encoding"); 198 uint64_t result = pd >> shift; 199 assert((result & CONST64(0xffffffff00000000)) == 0, "narrow oop overflow"); 200 assert(decode_heap_oop(result) == v, "reversibility"); 201 return (narrowOop)result; 202 } 203 204 inline narrowOop oopDesc::encode_heap_oop(oop v) { 205 return (is_null(v)) ? (narrowOop)0 : encode_heap_oop_not_null(v); 206 } 207 208 inline oop oopDesc::decode_heap_oop_not_null(narrowOop v) { 209 assert(!is_null(v), "narrow oop value can never be zero"); 210 address base = Universe::narrow_oop_base(); 211 int shift = Universe::narrow_oop_shift(); 212 oop result = (oop)(void*)((uintptr_t)base + ((uintptr_t)v << shift)); 213 assert(check_obj_alignment(result), err_msg("address not aligned: " PTR_FORMAT, p2i((void*) result))); 214 return result; 215 } 216 217 inline oop oopDesc::decode_heap_oop(narrowOop v) { 218 return is_null(v) ? (oop)NULL : decode_heap_oop_not_null(v); 219 } 220 221 inline oop oopDesc::decode_heap_oop_not_null(oop v) { return v; } 222 inline oop oopDesc::decode_heap_oop(oop v) { return v; } 223 224 // Load an oop out of the Java heap as is without decoding. 225 // Called by GC to check for null before decoding. 226 inline oop oopDesc::load_heap_oop(oop* p) { return *p; } 227 inline narrowOop oopDesc::load_heap_oop(narrowOop* p) { return *p; } 228 229 // Load and decode an oop out of the Java heap into a wide oop. 230 inline oop oopDesc::load_decode_heap_oop_not_null(oop* p) { return *p; } 231 inline oop oopDesc::load_decode_heap_oop_not_null(narrowOop* p) { 232 return decode_heap_oop_not_null(*p); 233 } 234 235 // Load and decode an oop out of the heap accepting null 236 inline oop oopDesc::load_decode_heap_oop(oop* p) { return *p; } 237 inline oop oopDesc::load_decode_heap_oop(narrowOop* p) { 238 return decode_heap_oop(*p); 239 } 240 241 // Store already encoded heap oop into the heap. 242 inline void oopDesc::store_heap_oop(oop* p, oop v) { *p = v; } 243 inline void oopDesc::store_heap_oop(narrowOop* p, narrowOop v) { *p = v; } 244 245 // Encode and store a heap oop. 246 inline void oopDesc::encode_store_heap_oop_not_null(narrowOop* p, oop v) { 247 *p = encode_heap_oop_not_null(v); 248 } 249 inline void oopDesc::encode_store_heap_oop_not_null(oop* p, oop v) { *p = v; } 250 251 // Encode and store a heap oop allowing for null. 252 inline void oopDesc::encode_store_heap_oop(narrowOop* p, oop v) { 253 *p = encode_heap_oop(v); 254 } 255 inline void oopDesc::encode_store_heap_oop(oop* p, oop v) { *p = v; } 256 257 // Store heap oop as is for volatile fields. 258 inline void oopDesc::release_store_heap_oop(volatile oop* p, oop v) { 259 OrderAccess::release_store_ptr(p, v); 260 } 261 inline void oopDesc::release_store_heap_oop(volatile narrowOop* p, 262 narrowOop v) { 263 OrderAccess::release_store(p, v); 264 } 265 266 inline void oopDesc::release_encode_store_heap_oop_not_null( 267 volatile narrowOop* p, oop v) { 268 // heap oop is not pointer sized. 269 OrderAccess::release_store(p, encode_heap_oop_not_null(v)); 270 } 271 272 inline void oopDesc::release_encode_store_heap_oop_not_null( 273 volatile oop* p, oop v) { 274 OrderAccess::release_store_ptr(p, v); 275 } 276 277 inline void oopDesc::release_encode_store_heap_oop(volatile oop* p, 278 oop v) { 279 OrderAccess::release_store_ptr(p, v); 280 } 281 inline void oopDesc::release_encode_store_heap_oop( 282 volatile narrowOop* p, oop v) { 283 OrderAccess::release_store(p, encode_heap_oop(v)); 284 } 285 286 287 // These functions are only used to exchange oop fields in instances, 288 // not headers. 289 inline oop oopDesc::atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest) { 290 if (UseCompressedOops) { 291 // encode exchange value from oop to T 292 narrowOop val = encode_heap_oop(exchange_value); 293 narrowOop old = (narrowOop)Atomic::xchg(val, (narrowOop*)dest); 294 // decode old from T to oop 295 return decode_heap_oop(old); 296 } else { 297 return (oop)Atomic::xchg_ptr(exchange_value, (oop*)dest); 298 } 299 } 300 301 // In order to put or get a field out of an instance, must first check 302 // if the field has been compressed and uncompress it. 303 inline oop oopDesc::obj_field(int offset) const { 304 return UseCompressedOops ? 305 load_decode_heap_oop(obj_field_addr<narrowOop>(offset)) : 306 load_decode_heap_oop(obj_field_addr<oop>(offset)); 307 } 308 inline volatile oop oopDesc::obj_field_volatile(int offset) const { 309 volatile oop value = obj_field(offset); 310 OrderAccess::acquire(); 311 return value; 312 } 313 inline void oopDesc::obj_field_put(int offset, oop value) { 314 UseCompressedOops ? oop_store(obj_field_addr<narrowOop>(offset), value) : 315 oop_store(obj_field_addr<oop>(offset), value); 316 } 317 318 inline Metadata* oopDesc::metadata_field(int offset) const { 319 return *metadata_field_addr(offset); 320 } 321 322 inline void oopDesc::metadata_field_put(int offset, Metadata* value) { 323 *metadata_field_addr(offset) = value; 324 } 325 326 inline void oopDesc::obj_field_put_raw(int offset, oop value) { 327 UseCompressedOops ? 328 encode_store_heap_oop(obj_field_addr<narrowOop>(offset), value) : 329 encode_store_heap_oop(obj_field_addr<oop>(offset), value); 330 } 331 inline void oopDesc::obj_field_put_volatile(int offset, oop value) { 332 OrderAccess::release(); 333 obj_field_put(offset, value); 334 OrderAccess::fence(); 335 } 336 337 inline jbyte oopDesc::byte_field(int offset) const { return (jbyte) *byte_field_addr(offset); } 338 inline void oopDesc::byte_field_put(int offset, jbyte contents) { *byte_field_addr(offset) = (jint) contents; } 339 340 inline jboolean oopDesc::bool_field(int offset) const { return (jboolean) *bool_field_addr(offset); } 341 inline void oopDesc::bool_field_put(int offset, jboolean contents) { *bool_field_addr(offset) = (jint) contents; } 342 343 inline jchar oopDesc::char_field(int offset) const { return (jchar) *char_field_addr(offset); } 344 inline void oopDesc::char_field_put(int offset, jchar contents) { *char_field_addr(offset) = (jint) contents; } 345 346 inline jint oopDesc::int_field(int offset) const { return *int_field_addr(offset); } 347 inline void oopDesc::int_field_put(int offset, jint contents) { *int_field_addr(offset) = contents; } 348 349 inline jshort oopDesc::short_field(int offset) const { return (jshort) *short_field_addr(offset); } 350 inline void oopDesc::short_field_put(int offset, jshort contents) { *short_field_addr(offset) = (jint) contents;} 351 352 inline jlong oopDesc::long_field(int offset) const { return *long_field_addr(offset); } 353 inline void oopDesc::long_field_put(int offset, jlong contents) { *long_field_addr(offset) = contents; } 354 355 inline jfloat oopDesc::float_field(int offset) const { return *float_field_addr(offset); } 356 inline void oopDesc::float_field_put(int offset, jfloat contents) { *float_field_addr(offset) = contents; } 357 358 inline jdouble oopDesc::double_field(int offset) const { return *double_field_addr(offset); } 359 inline void oopDesc::double_field_put(int offset, jdouble contents) { *double_field_addr(offset) = contents; } 360 361 inline address oopDesc::address_field(int offset) const { return *address_field_addr(offset); } 362 inline void oopDesc::address_field_put(int offset, address contents) { *address_field_addr(offset) = contents; } 363 364 inline oop oopDesc::obj_field_acquire(int offset) const { 365 return UseCompressedOops ? 366 decode_heap_oop((narrowOop) 367 OrderAccess::load_acquire(obj_field_addr<narrowOop>(offset))) 368 : decode_heap_oop((oop) 369 OrderAccess::load_ptr_acquire(obj_field_addr<oop>(offset))); 370 } 371 inline void oopDesc::release_obj_field_put(int offset, oop value) { 372 UseCompressedOops ? 373 oop_store((volatile narrowOop*)obj_field_addr<narrowOop>(offset), value) : 374 oop_store((volatile oop*) obj_field_addr<oop>(offset), value); 375 } 376 377 inline jbyte oopDesc::byte_field_acquire(int offset) const { return OrderAccess::load_acquire(byte_field_addr(offset)); } 378 inline void oopDesc::release_byte_field_put(int offset, jbyte contents) { OrderAccess::release_store(byte_field_addr(offset), contents); } 379 380 inline jboolean oopDesc::bool_field_acquire(int offset) const { return OrderAccess::load_acquire(bool_field_addr(offset)); } 381 inline void oopDesc::release_bool_field_put(int offset, jboolean contents) { OrderAccess::release_store(bool_field_addr(offset), contents); } 382 383 inline jchar oopDesc::char_field_acquire(int offset) const { return OrderAccess::load_acquire(char_field_addr(offset)); } 384 inline void oopDesc::release_char_field_put(int offset, jchar contents) { OrderAccess::release_store(char_field_addr(offset), contents); } 385 386 inline jint oopDesc::int_field_acquire(int offset) const { return OrderAccess::load_acquire(int_field_addr(offset)); } 387 inline void oopDesc::release_int_field_put(int offset, jint contents) { OrderAccess::release_store(int_field_addr(offset), contents); } 388 389 inline jshort oopDesc::short_field_acquire(int offset) const { return (jshort)OrderAccess::load_acquire(short_field_addr(offset)); } 390 inline void oopDesc::release_short_field_put(int offset, jshort contents) { OrderAccess::release_store(short_field_addr(offset), contents); } 391 392 inline jlong oopDesc::long_field_acquire(int offset) const { return OrderAccess::load_acquire(long_field_addr(offset)); } 393 inline void oopDesc::release_long_field_put(int offset, jlong contents) { OrderAccess::release_store(long_field_addr(offset), contents); } 394 395 inline jfloat oopDesc::float_field_acquire(int offset) const { return OrderAccess::load_acquire(float_field_addr(offset)); } 396 inline void oopDesc::release_float_field_put(int offset, jfloat contents) { OrderAccess::release_store(float_field_addr(offset), contents); } 397 398 inline jdouble oopDesc::double_field_acquire(int offset) const { return OrderAccess::load_acquire(double_field_addr(offset)); } 399 inline void oopDesc::release_double_field_put(int offset, jdouble contents) { OrderAccess::release_store(double_field_addr(offset), contents); } 400 401 inline address oopDesc::address_field_acquire(int offset) const { return (address) OrderAccess::load_ptr_acquire(address_field_addr(offset)); } 402 inline void oopDesc::release_address_field_put(int offset, address contents) { OrderAccess::release_store_ptr(address_field_addr(offset), contents); } 403 404 inline int oopDesc::size_given_klass(Klass* klass) { 405 int lh = klass->layout_helper(); 406 int s; 407 408 // lh is now a value computed at class initialization that may hint 409 // at the size. For instances, this is positive and equal to the 410 // size. For arrays, this is negative and provides log2 of the 411 // array element size. For other oops, it is zero and thus requires 412 // a virtual call. 413 // 414 // We go to all this trouble because the size computation is at the 415 // heart of phase 2 of mark-compaction, and called for every object, 416 // alive or dead. So the speed here is equal in importance to the 417 // speed of allocation. 418 419 if (lh > Klass::_lh_neutral_value) { 420 if (!Klass::layout_helper_needs_slow_path(lh)) { 421 s = lh >> LogHeapWordSize; // deliver size scaled by wordSize 422 } else { 423 s = klass->oop_size(this); 424 } 425 } else if (lh <= Klass::_lh_neutral_value) { 426 // The most common case is instances; fall through if so. 427 if (lh < Klass::_lh_neutral_value) { 428 // Second most common case is arrays. We have to fetch the 429 // length of the array, shift (multiply) it appropriately, 430 // up to wordSize, add the header, and align to object size. 431 size_t size_in_bytes; 432 #ifdef _M_IA64 433 // The Windows Itanium Aug 2002 SDK hoists this load above 434 // the check for s < 0. An oop at the end of the heap will 435 // cause an access violation if this load is performed on a non 436 // array oop. Making the reference volatile prohibits this. 437 // (%%% please explain by what magic the length is actually fetched!) 438 volatile int *array_length; 439 array_length = (volatile int *)( (intptr_t)this + 440 arrayOopDesc::length_offset_in_bytes() ); 441 assert(array_length > 0, "Integer arithmetic problem somewhere"); 442 // Put into size_t to avoid overflow. 443 size_in_bytes = (size_t) array_length; 444 size_in_bytes = size_in_bytes << Klass::layout_helper_log2_element_size(lh); 445 #else 446 size_t array_length = (size_t) ((arrayOop)this)->length(); 447 size_in_bytes = array_length << Klass::layout_helper_log2_element_size(lh); 448 #endif 449 size_in_bytes += Klass::layout_helper_header_size(lh); 450 451 // This code could be simplified, but by keeping array_header_in_bytes 452 // in units of bytes and doing it this way we can round up just once, 453 // skipping the intermediate round to HeapWordSize. Cast the result 454 // of round_to to size_t to guarantee unsigned division == right shift. 455 s = (int)((size_t)round_to(size_in_bytes, MinObjAlignmentInBytes) / 456 HeapWordSize); 457 458 // UseParNewGC, UseParallelGC and UseG1GC can change the length field 459 // of an "old copy" of an object array in the young gen so it indicates 460 // the grey portion of an already copied array. This will cause the first 461 // disjunct below to fail if the two comparands are computed across such 462 // a concurrent change. 463 // UseParNewGC also runs with promotion labs (which look like int 464 // filler arrays) which are subject to changing their declared size 465 // when finally retiring a PLAB; this also can cause the first disjunct 466 // to fail for another worker thread that is concurrently walking the block 467 // offset table. Both these invariant failures are benign for their 468 // current uses; we relax the assertion checking to cover these two cases below: 469 // is_objArray() && is_forwarded() // covers first scenario above 470 // || is_typeArray() // covers second scenario above 471 // If and when UseParallelGC uses the same obj array oop stealing/chunking 472 // technique, we will need to suitably modify the assertion. 473 assert((s == klass->oop_size(this)) || 474 (Universe::heap()->is_gc_active() && 475 ((is_typeArray() && UseParNewGC) || 476 (is_objArray() && is_forwarded() && (UseParNewGC || UseParallelGC || UseG1GC)))), 477 "wrong array object size"); 478 } else { 479 // Must be zero, so bite the bullet and take the virtual call. 480 s = klass->oop_size(this); 481 } 482 } 483 484 assert(s % MinObjAlignment == 0, "alignment check"); 485 assert(s > 0, "Bad size calculated"); 486 return s; 487 } 488 489 490 inline int oopDesc::size() { 491 return size_given_klass(klass()); 492 } 493 494 inline void update_barrier_set(void* p, oop v, bool release = false) { 495 assert(oopDesc::bs() != NULL, "Uninitialized bs in oop!"); 496 oopDesc::bs()->write_ref_field(p, v, release); 497 } 498 499 template <class T> inline void update_barrier_set_pre(T* p, oop v) { 500 oopDesc::bs()->write_ref_field_pre(p, v); 501 } 502 503 template <class T> inline void oop_store(T* p, oop v) { 504 if (always_do_update_barrier) { 505 oop_store((volatile T*)p, v); 506 } else { 507 update_barrier_set_pre(p, v); 508 oopDesc::encode_store_heap_oop(p, v); 509 // always_do_update_barrier == false => 510 // Either we are at a safepoint (in GC) or CMS is not used. In both 511 // cases it's unnecessary to mark the card as dirty with release sematics. 512 update_barrier_set((void*)p, v, false /* release */); // cast away type 513 } 514 } 515 516 template <class T> inline void oop_store(volatile T* p, oop v) { 517 update_barrier_set_pre((T*)p, v); // cast away volatile 518 // Used by release_obj_field_put, so use release_store_ptr. 519 oopDesc::release_encode_store_heap_oop(p, v); 520 // When using CMS we must mark the card corresponding to p as dirty 521 // with release sematics to prevent that CMS sees the dirty card but 522 // not the new value v at p due to reordering of the two 523 // stores. Note that CMS has a concurrent precleaning phase, where 524 // it reads the card table while the Java threads are running. 525 update_barrier_set((void*)p, v, true /* release */); // cast away type 526 } 527 528 // Should replace *addr = oop assignments where addr type depends on UseCompressedOops 529 // (without having to remember the function name this calls). 530 inline void oop_store_raw(HeapWord* addr, oop value) { 531 if (UseCompressedOops) { 532 oopDesc::encode_store_heap_oop((narrowOop*)addr, value); 533 } else { 534 oopDesc::encode_store_heap_oop((oop*)addr, value); 535 } 536 } 537 538 inline oop oopDesc::atomic_compare_exchange_oop(oop exchange_value, 539 volatile HeapWord *dest, 540 oop compare_value, 541 bool prebarrier) { 542 if (UseCompressedOops) { 543 if (prebarrier) { 544 update_barrier_set_pre((narrowOop*)dest, exchange_value); 545 } 546 // encode exchange and compare value from oop to T 547 narrowOop val = encode_heap_oop(exchange_value); 548 narrowOop cmp = encode_heap_oop(compare_value); 549 550 narrowOop old = (narrowOop) Atomic::cmpxchg(val, (narrowOop*)dest, cmp); 551 // decode old from T to oop 552 return decode_heap_oop(old); 553 } else { 554 if (prebarrier) { 555 update_barrier_set_pre((oop*)dest, exchange_value); 556 } 557 return (oop)Atomic::cmpxchg_ptr(exchange_value, (oop*)dest, compare_value); 558 } 559 } 560 561 // Used only for markSweep, scavenging 562 inline bool oopDesc::is_gc_marked() const { 563 return mark()->is_marked(); 564 } 565 566 inline bool oopDesc::is_locked() const { 567 return mark()->is_locked(); 568 } 569 570 inline bool oopDesc::is_unlocked() const { 571 return mark()->is_unlocked(); 572 } 573 574 inline bool oopDesc::has_bias_pattern() const { 575 return mark()->has_bias_pattern(); 576 } 577 578 579 // used only for asserts 580 inline bool oopDesc::is_oop(bool ignore_mark_word) const { 581 oop obj = (oop) this; 582 if (!check_obj_alignment(obj)) return false; 583 if (!Universe::heap()->is_in_reserved(obj)) return false; 584 // obj is aligned and accessible in heap 585 if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false; 586 587 // Header verification: the mark is typically non-NULL. If we're 588 // at a safepoint, it must not be null. 589 // Outside of a safepoint, the header could be changing (for example, 590 // another thread could be inflating a lock on this object). 591 if (ignore_mark_word) { 592 return true; 593 } 594 if (mark() != NULL) { 595 return true; 596 } 597 return !SafepointSynchronize::is_at_safepoint(); 598 } 599 600 601 // used only for asserts 602 inline bool oopDesc::is_oop_or_null(bool ignore_mark_word) const { 603 return this == NULL ? true : is_oop(ignore_mark_word); 604 } 605 606 #ifndef PRODUCT 607 // used only for asserts 608 inline bool oopDesc::is_unlocked_oop() const { 609 if (!Universe::heap()->is_in_reserved(this)) return false; 610 return mark()->is_unlocked(); 611 } 612 #endif // PRODUCT 613 614 inline void oopDesc::follow_contents(void) { 615 assert (is_gc_marked(), "should be marked"); 616 klass()->oop_follow_contents(this); 617 } 618 619 // Used by scavengers 620 621 inline bool oopDesc::is_forwarded() const { 622 // The extra heap check is needed since the obj might be locked, in which case the 623 // mark would point to a stack location and have the sentinel bit cleared 624 return mark()->is_marked(); 625 } 626 627 // Used by scavengers 628 inline void oopDesc::forward_to(oop p) { 629 assert(check_obj_alignment(p), 630 "forwarding to something not aligned"); 631 assert(Universe::heap()->is_in_reserved(p), 632 "forwarding to something not in heap"); 633 markOop m = markOopDesc::encode_pointer_as_mark(p); 634 assert(m->decode_pointer() == p, "encoding must be reversable"); 635 set_mark(m); 636 } 637 638 // Used by parallel scavengers 639 inline bool oopDesc::cas_forward_to(oop p, markOop compare) { 640 assert(check_obj_alignment(p), 641 "forwarding to something not aligned"); 642 assert(Universe::heap()->is_in_reserved(p), 643 "forwarding to something not in heap"); 644 markOop m = markOopDesc::encode_pointer_as_mark(p); 645 assert(m->decode_pointer() == p, "encoding must be reversable"); 646 return cas_set_mark(m, compare) == compare; 647 } 648 649 // Note that the forwardee is not the same thing as the displaced_mark. 650 // The forwardee is used when copying during scavenge and mark-sweep. 651 // It does need to clear the low two locking- and GC-related bits. 652 inline oop oopDesc::forwardee() const { 653 return (oop) mark()->decode_pointer(); 654 } 655 656 inline bool oopDesc::has_displaced_mark() const { 657 return mark()->has_displaced_mark_helper(); 658 } 659 660 inline markOop oopDesc::displaced_mark() const { 661 return mark()->displaced_mark_helper(); 662 } 663 664 inline void oopDesc::set_displaced_mark(markOop m) { 665 mark()->set_displaced_mark_helper(m); 666 } 667 668 // The following method needs to be MT safe. 669 inline uint oopDesc::age() const { 670 assert(!is_forwarded(), "Attempt to read age from forwarded mark"); 671 if (has_displaced_mark()) { 672 return displaced_mark()->age(); 673 } else { 674 return mark()->age(); 675 } 676 } 677 678 inline void oopDesc::incr_age() { 679 assert(!is_forwarded(), "Attempt to increment age of forwarded mark"); 680 if (has_displaced_mark()) { 681 set_displaced_mark(displaced_mark()->incr_age()); 682 } else { 683 set_mark(mark()->incr_age()); 684 } 685 } 686 687 688 inline intptr_t oopDesc::identity_hash() { 689 // Fast case; if the object is unlocked and the hash value is set, no locking is needed 690 // Note: The mark must be read into local variable to avoid concurrent updates. 691 markOop mrk = mark(); 692 if (mrk->is_unlocked() && !mrk->has_no_hash()) { 693 return mrk->hash(); 694 } else if (mrk->is_marked()) { 695 return mrk->hash(); 696 } else { 697 return slow_identity_hash(); 698 } 699 } 700 701 inline int oopDesc::adjust_pointers() { 702 debug_only(int check_size = size()); 703 int s = klass()->oop_adjust_pointers(this); 704 assert(s == check_size, "should be the same"); 705 return s; 706 } 707 708 #define OOP_ITERATE_DEFN(OopClosureType, nv_suffix) \ 709 \ 710 inline int oopDesc::oop_iterate(OopClosureType* blk) { \ 711 SpecializationStats::record_call(); \ 712 return klass()->oop_oop_iterate##nv_suffix(this, blk); \ 713 } \ 714 \ 715 inline int oopDesc::oop_iterate(OopClosureType* blk, MemRegion mr) { \ 716 SpecializationStats::record_call(); \ 717 return klass()->oop_oop_iterate##nv_suffix##_m(this, blk, mr); \ 718 } 719 720 721 inline int oopDesc::oop_iterate_no_header(OopClosure* blk) { 722 // The NoHeaderExtendedOopClosure wraps the OopClosure and proxies all 723 // the do_oop calls, but turns off all other features in ExtendedOopClosure. 724 NoHeaderExtendedOopClosure cl(blk); 725 return oop_iterate(&cl); 726 } 727 728 inline int oopDesc::oop_iterate_no_header(OopClosure* blk, MemRegion mr) { 729 NoHeaderExtendedOopClosure cl(blk); 730 return oop_iterate(&cl, mr); 731 } 732 733 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DEFN) 734 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DEFN) 735 736 #if INCLUDE_ALL_GCS 737 #define OOP_ITERATE_BACKWARDS_DEFN(OopClosureType, nv_suffix) \ 738 \ 739 inline int oopDesc::oop_iterate_backwards(OopClosureType* blk) { \ 740 SpecializationStats::record_call(); \ 741 return klass()->oop_oop_iterate_backwards##nv_suffix(this, blk); \ 742 } 743 744 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DEFN) 745 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DEFN) 746 #endif // INCLUDE_ALL_GCS 747 748 #endif // SHARE_VM_OOPS_OOP_INLINE_HPP