oop.hpp revision 342:37f87013dfd8
155714Skris/* 255714Skris * Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved. 355714Skris * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 455714Skris * 555714Skris * This code is free software; you can redistribute it and/or modify it 655714Skris * under the terms of the GNU General Public License version 2 only, as 755714Skris * published by the Free Software Foundation. 855714Skris * 955714Skris * This code is distributed in the hope that it will be useful, but WITHOUT 1055714Skris * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1155714Skris * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1255714Skris * version 2 for more details (a copy is included in the LICENSE file that 1355714Skris * accompanied this code). 1455714Skris * 1555714Skris * You should have received a copy of the GNU General Public License version 1655714Skris * 2 along with this work; if not, write to the Free Software Foundation, 1755714Skris * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 1855714Skris * 1955714Skris * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 2055714Skris * CA 95054 USA or visit www.sun.com if you need additional information or 2155714Skris * have any questions. 2255714Skris * 2355714Skris */ 2455714Skris 2555714Skris// oopDesc is the top baseclass for objects classes. The {name}Desc classes describe 2655714Skris// the format of Java objects so the fields can be accessed from C++. 2755714Skris// oopDesc is abstract. 2855714Skris// (see oopHierarchy for complete oop class hierarchy) 2955714Skris// 3055714Skris// no virtual functions allowed 3155714Skris 3255714Skris// store into oop with store check 3355714Skristemplate <class T> void oop_store(T* p, oop v); 3455714Skristemplate <class T> void oop_store(volatile T* p, oop v); 3555714Skris 3655714Skris// store into oop without store check 3755714Skristemplate <class T> void oop_store_without_check(T* p, oop v); 3855714Skristemplate <class T> void oop_store_without_check(volatile T* p, oop v); 3955714Skris 4055714Skris 4155714Skrisextern bool always_do_update_barrier; 4255714Skris 4355714Skris// Forward declarations. 4455714Skrisclass OopClosure; 4555714Skrisclass ScanClosure; 4655714Skrisclass FastScanClosure; 4755714Skrisclass FilteringClosure; 4855714Skrisclass BarrierSet; 4955714Skrisclass CMSIsAliveClosure; 5055714Skris 5155714Skrisclass PSPromotionManager; 5255714Skrisclass ParCompactionManager; 5355714Skris 5455714Skrisclass oopDesc { 5555714Skris friend class VMStructs; 5655714Skris private: 5755714Skris volatile markOop _mark; 5855714Skris union _metadata { 5955714Skris wideKlassOop _klass; 6055714Skris narrowOop _compressed_klass; 6155714Skris } _metadata; 6255714Skris 6355714Skris // Fast access to barrier set. Must be initialized. 6455714Skris static BarrierSet* _bs; 6555714Skris 6655714Skris public: 6755714Skris markOop mark() const { return _mark; } 6855714Skris markOop* mark_addr() const { return (markOop*) &_mark; } 6955714Skris 7055714Skris void set_mark(volatile markOop m) { _mark = m; } 7155714Skris 7255714Skris void release_set_mark(markOop m); 7355714Skris markOop cas_set_mark(markOop new_mark, markOop old_mark); 7455714Skris 7555714Skris // Used only to re-initialize the mark word (e.g., of promoted 7655714Skris // objects during a GC) -- requires a valid klass pointer 7755714Skris void init_mark(); 7855714Skris 7955714Skris klassOop klass() const; 8055714Skris oop* klass_addr(); 8155714Skris narrowOop* compressed_klass_addr(); 8255714Skris 8355714Skris void set_klass(klassOop k); 8455714Skris // For when the klass pointer is being used as a linked list "next" field. 8555714Skris void set_klass_to_list_ptr(oop k); 8655714Skris 8755714Skris // size of object header, aligned to platform wordSize 8855714Skris static int header_size() { return sizeof(oopDesc)/HeapWordSize; } 8955714Skris 9055714Skris Klass* blueprint() const; 9155714Skris 9255714Skris // Returns whether this is an instance of k or an instance of a subclass of k 9355714Skris bool is_a(klassOop k) const; 9455714Skris 9555714Skris // Returns the actual oop size of the object 9655714Skris int size(); 9755714Skris 9855714Skris // Sometimes (for complicated concurrency-related reasons), it is useful 9955714Skris // to be able to figure out the size of an object knowing its klass. 10055714Skris int size_given_klass(Klass* klass); 10155714Skris 10255714Skris // Some perm gen objects are not parseble immediately after 10355714Skris // installation of their klass pointer. 10455714Skris bool is_parsable(); 10555714Skris 10655714Skris // type test operations (inlined in oop.inline.h) 10755714Skris bool is_instance() const; 10855714Skris bool is_instanceRef() const; 10955714Skris bool is_array() const; 11055714Skris bool is_objArray() const; 11155714Skris bool is_symbol() const; 11255714Skris bool is_klass() const; 11355714Skris bool is_thread() const; 11455714Skris bool is_method() const; 115 bool is_constMethod() const; 116 bool is_methodData() const; 117 bool is_constantPool() const; 118 bool is_constantPoolCache() const; 119 bool is_typeArray() const; 120 bool is_javaArray() const; 121 bool is_compiledICHolder() const; 122 123 private: 124 // field addresses in oop 125 void* field_base(int offset) const; 126 127 jbyte* byte_field_addr(int offset) const; 128 jchar* char_field_addr(int offset) const; 129 jboolean* bool_field_addr(int offset) const; 130 jint* int_field_addr(int offset) const; 131 jshort* short_field_addr(int offset) const; 132 jlong* long_field_addr(int offset) const; 133 jfloat* float_field_addr(int offset) const; 134 jdouble* double_field_addr(int offset) const; 135 address* address_field_addr(int offset) const; 136 137 public: 138 // Need this as public for garbage collection. 139 template <class T> T* obj_field_addr(int offset) const; 140 141 // Oop encoding heap max 142 static const uint64_t OopEncodingHeapMax = 143 (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes; 144 145 static bool is_null(oop obj); 146 static bool is_null(narrowOop obj); 147 148 // Decode an oop pointer from a narrowOop if compressed. 149 // These are overloaded for oop and narrowOop as are the other functions 150 // below so that they can be called in template functions. 151 static oop decode_heap_oop_not_null(oop v); 152 static oop decode_heap_oop_not_null(narrowOop v); 153 static oop decode_heap_oop(oop v); 154 static oop decode_heap_oop(narrowOop v); 155 156 // Encode an oop pointer to a narrow oop. The or_null versions accept 157 // null oop pointer, others do not in order to eliminate the 158 // null checking branches. 159 static narrowOop encode_heap_oop_not_null(oop v); 160 static narrowOop encode_heap_oop(oop v); 161 162 // Load an oop out of the Java heap 163 static narrowOop load_heap_oop(narrowOop* p); 164 static oop load_heap_oop(oop* p); 165 166 // Load an oop out of Java heap and decode it to an uncompressed oop. 167 static oop load_decode_heap_oop_not_null(narrowOop* p); 168 static oop load_decode_heap_oop_not_null(oop* p); 169 static oop load_decode_heap_oop(narrowOop* p); 170 static oop load_decode_heap_oop(oop* p); 171 172 // Store an oop into the heap. 173 static void store_heap_oop(narrowOop* p, narrowOop v); 174 static void store_heap_oop(oop* p, oop v); 175 176 // Encode oop if UseCompressedOops and store into the heap. 177 static void encode_store_heap_oop_not_null(narrowOop* p, oop v); 178 static void encode_store_heap_oop_not_null(oop* p, oop v); 179 static void encode_store_heap_oop(narrowOop* p, oop v); 180 static void encode_store_heap_oop(oop* p, oop v); 181 182 static void release_store_heap_oop(volatile narrowOop* p, narrowOop v); 183 static void release_store_heap_oop(volatile oop* p, oop v); 184 185 static void release_encode_store_heap_oop_not_null(volatile narrowOop* p, oop v); 186 static void release_encode_store_heap_oop_not_null(volatile oop* p, oop v); 187 static void release_encode_store_heap_oop(volatile narrowOop* p, oop v); 188 static void release_encode_store_heap_oop(volatile oop* p, oop v); 189 190 static oop atomic_exchange_oop(oop exchange_value, volatile HeapWord *dest); 191 static oop atomic_compare_exchange_oop(oop exchange_value, 192 volatile HeapWord *dest, 193 oop compare_value); 194 195 // Access to fields in a instanceOop through these methods. 196 oop obj_field(int offset) const; 197 void obj_field_put(int offset, oop value); 198 void obj_field_raw_put(int offset, oop value); 199 200 jbyte byte_field(int offset) const; 201 void byte_field_put(int offset, jbyte contents); 202 203 jchar char_field(int offset) const; 204 void char_field_put(int offset, jchar contents); 205 206 jboolean bool_field(int offset) const; 207 void bool_field_put(int offset, jboolean contents); 208 209 jint int_field(int offset) const; 210 void int_field_put(int offset, jint contents); 211 212 jshort short_field(int offset) const; 213 void short_field_put(int offset, jshort contents); 214 215 jlong long_field(int offset) const; 216 void long_field_put(int offset, jlong contents); 217 218 jfloat float_field(int offset) const; 219 void float_field_put(int offset, jfloat contents); 220 221 jdouble double_field(int offset) const; 222 void double_field_put(int offset, jdouble contents); 223 224 address address_field(int offset) const; 225 void address_field_put(int offset, address contents); 226 227 oop obj_field_acquire(int offset) const; 228 void release_obj_field_put(int offset, oop value); 229 230 jbyte byte_field_acquire(int offset) const; 231 void release_byte_field_put(int offset, jbyte contents); 232 233 jchar char_field_acquire(int offset) const; 234 void release_char_field_put(int offset, jchar contents); 235 236 jboolean bool_field_acquire(int offset) const; 237 void release_bool_field_put(int offset, jboolean contents); 238 239 jint int_field_acquire(int offset) const; 240 void release_int_field_put(int offset, jint contents); 241 242 jshort short_field_acquire(int offset) const; 243 void release_short_field_put(int offset, jshort contents); 244 245 jlong long_field_acquire(int offset) const; 246 void release_long_field_put(int offset, jlong contents); 247 248 jfloat float_field_acquire(int offset) const; 249 void release_float_field_put(int offset, jfloat contents); 250 251 jdouble double_field_acquire(int offset) const; 252 void release_double_field_put(int offset, jdouble contents); 253 254 // printing functions for VM debugging 255 void print_on(outputStream* st) const; // First level print 256 void print_value_on(outputStream* st) const; // Second level print. 257 void print_address_on(outputStream* st) const; // Address printing 258 259 // printing on default output stream 260 void print(); 261 void print_value(); 262 void print_address(); 263 264 // return the print strings 265 char* print_string(); 266 char* print_value_string(); 267 268 // verification operations 269 void verify_on(outputStream* st); 270 void verify(); 271 void verify_old_oop(oop* p, bool allow_dirty); 272 void verify_old_oop(narrowOop* p, bool allow_dirty); 273 274 // tells whether this oop is partially constructed (gc during class loading) 275 bool partially_loaded(); 276 void set_partially_loaded(); 277 278 // locking operations 279 bool is_locked() const; 280 bool is_unlocked() const; 281 bool has_bias_pattern() const; 282 283 // asserts 284 bool is_oop(bool ignore_mark_word = false) const; 285 bool is_oop_or_null(bool ignore_mark_word = false) const; 286#ifndef PRODUCT 287 bool is_unlocked_oop() const; 288#endif 289 290 // garbage collection 291 bool is_gc_marked() const; 292 // Apply "MarkSweep::mark_and_push" to (the address of) every non-NULL 293 // reference field in "this". 294 void follow_contents(void); 295 void follow_header(void); 296 297#ifndef SERIALGC 298 // Parallel Scavenge 299 void copy_contents(PSPromotionManager* pm); 300 void push_contents(PSPromotionManager* pm); 301 302 // Parallel Old 303 void update_contents(ParCompactionManager* cm); 304 void update_contents(ParCompactionManager* cm, 305 HeapWord* begin_limit, 306 HeapWord* end_limit); 307 void update_contents(ParCompactionManager* cm, 308 klassOop old_klass, 309 HeapWord* begin_limit, 310 HeapWord* end_limit); 311 312 void follow_contents(ParCompactionManager* cm); 313 void follow_header(ParCompactionManager* cm); 314#endif // SERIALGC 315 316 bool is_perm() const; 317 bool is_perm_or_null() const; 318 bool is_shared() const; 319 bool is_shared_readonly() const; 320 bool is_shared_readwrite() const; 321 322 // Forward pointer operations for scavenge 323 bool is_forwarded() const; 324 325 void forward_to(oop p); 326 bool cas_forward_to(oop p, markOop compare); 327 328#ifndef SERIALGC 329 // Like "forward_to", but inserts the forwarding pointer atomically. 330 // Exactly one thread succeeds in inserting the forwarding pointer, and 331 // this call returns "NULL" for that thread; any other thread has the 332 // value of the forwarding pointer returned and does not modify "this". 333 oop forward_to_atomic(oop p); 334#endif // SERIALGC 335 336 oop forwardee() const; 337 338 // Age of object during scavenge 339 int age() const; 340 void incr_age(); 341 342 // Adjust all pointers in this object to point at it's forwarded location and 343 // return the size of this oop. This is used by the MarkSweep collector. 344 int adjust_pointers(); 345 void adjust_header(); 346 347#ifndef SERIALGC 348 // Parallel old 349 void update_header(); 350 void update_header(HeapWord* beg_addr, HeapWord* end_addr); 351#endif // SERIALGC 352 353 // mark-sweep support 354 void follow_body(int begin, int end); 355 356 // Fast access to barrier set 357 static BarrierSet* bs() { return _bs; } 358 static void set_bs(BarrierSet* bs) { _bs = bs; } 359 360 // iterators, returns size of object 361#define OOP_ITERATE_DECL(OopClosureType, nv_suffix) \ 362 int oop_iterate(OopClosureType* blk); \ 363 int oop_iterate(OopClosureType* blk, MemRegion mr); // Only in mr. 364 365 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_DECL) 366 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_DECL) 367 368#ifndef SERIALGC 369 370#define OOP_ITERATE_BACKWARDS_DECL(OopClosureType, nv_suffix) \ 371 int oop_iterate_backwards(OopClosureType* blk); 372 373 ALL_OOP_OOP_ITERATE_CLOSURES_1(OOP_ITERATE_BACKWARDS_DECL) 374 ALL_OOP_OOP_ITERATE_CLOSURES_2(OOP_ITERATE_BACKWARDS_DECL) 375#endif 376 377 void oop_iterate_header(OopClosure* blk); 378 void oop_iterate_header(OopClosure* blk, MemRegion mr); 379 380 // identity hash; returns the identity hash key (computes it if necessary) 381 // NOTE with the introduction of UseBiasedLocking that identity_hash() might reach a 382 // safepoint if called on a biased object. Calling code must be aware of that. 383 intptr_t identity_hash(); 384 intptr_t slow_identity_hash(); 385 386 // marks are forwarded to stack when object is locked 387 bool has_displaced_mark() const; 388 markOop displaced_mark() const; 389 void set_displaced_mark(markOop m); 390 391 // for code generation 392 static int mark_offset_in_bytes() { return offset_of(oopDesc, _mark); } 393 static int klass_offset_in_bytes() { return offset_of(oopDesc, _metadata._klass); } 394 static int klass_gap_offset_in_bytes(); 395}; 396