universe.hpp revision 2062:3582bf76420e
1/* 2 * Copyright (c) 1997, 2010, 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_MEMORY_UNIVERSE_HPP 26#define SHARE_VM_MEMORY_UNIVERSE_HPP 27 28#include "runtime/handles.hpp" 29#include "utilities/growableArray.hpp" 30 31// Universe is a name space holding known system classes and objects in the VM. 32// 33// Loaded classes are accessible through the SystemDictionary. 34// 35// The object heap is allocated and accessed through Universe, and various allocation 36// support is provided. Allocation by the interpreter and compiled code is done inline 37// and bails out to Scavenge::invoke_and_allocate. 38 39class CollectedHeap; 40class DeferredObjAllocEvent; 41 42 43// Common parts of a methodOop cache. This cache safely interacts with 44// the RedefineClasses API. 45// 46class CommonMethodOopCache : public CHeapObj { 47 // We save the klassOop and the idnum of methodOop in order to get 48 // the current cached methodOop. 49 private: 50 klassOop _klass; 51 int _method_idnum; 52 53 public: 54 CommonMethodOopCache() { _klass = NULL; _method_idnum = -1; } 55 ~CommonMethodOopCache() { _klass = NULL; _method_idnum = -1; } 56 57 void init(klassOop k, methodOop m, TRAPS); 58 klassOop klass() const { return _klass; } 59 int method_idnum() const { return _method_idnum; } 60 61 // GC support 62 void oops_do(OopClosure* f) { f->do_oop((oop*)&_klass); } 63}; 64 65 66// A helper class for caching a methodOop when the user of the cache 67// cares about all versions of the methodOop. 68// 69class ActiveMethodOopsCache : public CommonMethodOopCache { 70 // This subclass adds weak references to older versions of the 71 // methodOop and a query method for a methodOop. 72 73 private: 74 // If the cached methodOop has not been redefined, then 75 // _prev_methods will be NULL. If all of the previous 76 // versions of the method have been collected, then 77 // _prev_methods can have a length of zero. 78 GrowableArray<jweak>* _prev_methods; 79 80 public: 81 ActiveMethodOopsCache() { _prev_methods = NULL; } 82 ~ActiveMethodOopsCache(); 83 84 void add_previous_version(const methodOop method); 85 bool is_same_method(const methodOop method) const; 86}; 87 88 89// A helper class for caching a methodOop when the user of the cache 90// only cares about the latest version of the methodOop. 91// 92class LatestMethodOopCache : public CommonMethodOopCache { 93 // This subclass adds a getter method for the latest methodOop. 94 95 public: 96 methodOop get_methodOop(); 97}; 98 99// For UseCompressedOops. 100struct NarrowOopStruct { 101 // Base address for oop-within-java-object materialization. 102 // NULL if using wide oops or zero based narrow oops. 103 address _base; 104 // Number of shift bits for encoding/decoding narrow oops. 105 // 0 if using wide oops or zero based unscaled narrow oops, 106 // LogMinObjAlignmentInBytes otherwise. 107 int _shift; 108 // Generate code with implicit null checks for narrow oops. 109 bool _use_implicit_null_checks; 110}; 111 112 113class Universe: AllStatic { 114 // Ugh. Universe is much too friendly. 115 friend class MarkSweep; 116 friend class oopDesc; 117 friend class ClassLoader; 118 friend class Arguments; 119 friend class SystemDictionary; 120 friend class VMStructs; 121 friend class CompactingPermGenGen; 122 friend class VM_PopulateDumpSharedSpace; 123 124 friend jint universe_init(); 125 friend void universe2_init(); 126 friend bool universe_post_init(); 127 128 private: 129 // Known classes in the VM 130 static klassOop _boolArrayKlassObj; 131 static klassOop _byteArrayKlassObj; 132 static klassOop _charArrayKlassObj; 133 static klassOop _intArrayKlassObj; 134 static klassOop _shortArrayKlassObj; 135 static klassOop _longArrayKlassObj; 136 static klassOop _singleArrayKlassObj; 137 static klassOop _doubleArrayKlassObj; 138 static klassOop _typeArrayKlassObjs[T_VOID+1]; 139 140 static klassOop _objectArrayKlassObj; 141 142 static klassOop _methodKlassObj; 143 static klassOop _constMethodKlassObj; 144 static klassOop _methodDataKlassObj; 145 static klassOop _klassKlassObj; 146 static klassOop _arrayKlassKlassObj; 147 static klassOop _objArrayKlassKlassObj; 148 static klassOop _typeArrayKlassKlassObj; 149 static klassOop _instanceKlassKlassObj; 150 static klassOop _constantPoolKlassObj; 151 static klassOop _constantPoolCacheKlassObj; 152 static klassOop _compiledICHolderKlassObj; 153 static klassOop _systemObjArrayKlassObj; 154 155 // Known objects in the VM 156 157 // Primitive objects 158 static oop _int_mirror; 159 static oop _float_mirror; 160 static oop _double_mirror; 161 static oop _byte_mirror; 162 static oop _bool_mirror; 163 static oop _char_mirror; 164 static oop _long_mirror; 165 static oop _short_mirror; 166 static oop _void_mirror; 167 168 static oop _main_thread_group; // Reference to the main thread group object 169 static oop _system_thread_group; // Reference to the system thread group object 170 171 static typeArrayOop _the_empty_byte_array; // Canonicalized byte array 172 static typeArrayOop _the_empty_short_array; // Canonicalized short array 173 static typeArrayOop _the_empty_int_array; // Canonicalized int array 174 static objArrayOop _the_empty_system_obj_array; // Canonicalized system obj array 175 static objArrayOop _the_empty_class_klass_array; // Canonicalized obj array of type java.lang.Class 176 static objArrayOop _the_array_interfaces_array; // Canonicalized 2-array of cloneable & serializable klasses 177 static oop _the_null_string; // A cache of "null" as a Java string 178 static oop _the_min_jint_string; // A cache of "-2147483648" as a Java string 179 static LatestMethodOopCache* _finalizer_register_cache; // static method for registering finalizable objects 180 static LatestMethodOopCache* _loader_addClass_cache; // method for registering loaded classes in class loader vector 181 static ActiveMethodOopsCache* _reflect_invoke_cache; // method for security checks 182 static oop _out_of_memory_error_java_heap; // preallocated error object (no backtrace) 183 static oop _out_of_memory_error_perm_gen; // preallocated error object (no backtrace) 184 static oop _out_of_memory_error_array_size;// preallocated error object (no backtrace) 185 static oop _out_of_memory_error_gc_overhead_limit; // preallocated error object (no backtrace) 186 187 // array of preallocated error objects with backtrace 188 static objArrayOop _preallocated_out_of_memory_error_array; 189 190 // number of preallocated error objects available for use 191 static volatile jint _preallocated_out_of_memory_error_avail_count; 192 193 static oop _null_ptr_exception_instance; // preallocated exception object 194 static oop _arithmetic_exception_instance; // preallocated exception object 195 static oop _virtual_machine_error_instance; // preallocated exception object 196 // The object used as an exception dummy when exceptions are thrown for 197 // the vm thread. 198 static oop _vm_exception; 199 200 // The particular choice of collected heap. 201 static CollectedHeap* _collectedHeap; 202 203 // For UseCompressedOops. 204 static struct NarrowOopStruct _narrow_oop; 205 206 // array of dummy objects used with +FullGCAlot 207 debug_only(static objArrayOop _fullgc_alot_dummy_array;) 208 // index of next entry to clear 209 debug_only(static int _fullgc_alot_dummy_next;) 210 211 // Compiler/dispatch support 212 static int _base_vtable_size; // Java vtbl size of klass Object (in words) 213 214 // Initialization 215 static bool _bootstrapping; // true during genesis 216 static bool _fully_initialized; // true after universe_init and initialize_vtables called 217 218 // the array of preallocated errors with backtraces 219 static objArrayOop preallocated_out_of_memory_errors() { return _preallocated_out_of_memory_error_array; } 220 221 // generate an out of memory error; if possible using an error with preallocated backtrace; 222 // otherwise return the given default error. 223 static oop gen_out_of_memory_error(oop default_err); 224 225 // Historic gc information 226 static size_t _heap_capacity_at_last_gc; 227 static size_t _heap_used_at_last_gc; 228 229 static jint initialize_heap(); 230 static void initialize_basic_type_mirrors(TRAPS); 231 static void fixup_mirrors(TRAPS); 232 233 static void reinitialize_vtable_of(KlassHandle h_k, TRAPS); 234 static void reinitialize_itables(TRAPS); 235 static void compute_base_vtable_size(); // compute vtable size of class Object 236 237 static void genesis(TRAPS); // Create the initial world 238 239 // Mirrors for primitive classes (created eagerly) 240 static oop check_mirror(oop m) { 241 assert(m != NULL, "mirror not initialized"); 242 return m; 243 } 244 245 // Debugging 246 static int _verify_count; // number of verifies done 247 // True during call to verify(). Should only be set/cleared in verify(). 248 static bool _verify_in_progress; 249 250 static void compute_verify_oop_data(); 251 252 public: 253 // Known classes in the VM 254 static klassOop boolArrayKlassObj() { return _boolArrayKlassObj; } 255 static klassOop byteArrayKlassObj() { return _byteArrayKlassObj; } 256 static klassOop charArrayKlassObj() { return _charArrayKlassObj; } 257 static klassOop intArrayKlassObj() { return _intArrayKlassObj; } 258 static klassOop shortArrayKlassObj() { return _shortArrayKlassObj; } 259 static klassOop longArrayKlassObj() { return _longArrayKlassObj; } 260 static klassOop singleArrayKlassObj() { return _singleArrayKlassObj; } 261 static klassOop doubleArrayKlassObj() { return _doubleArrayKlassObj; } 262 263 static klassOop objectArrayKlassObj() { 264 return _objectArrayKlassObj; 265 } 266 267 static klassOop typeArrayKlassObj(BasicType t) { 268 assert((uint)t < T_VOID+1, "range check"); 269 assert(_typeArrayKlassObjs[t] != NULL, "domain check"); 270 return _typeArrayKlassObjs[t]; 271 } 272 273 static klassOop methodKlassObj() { return _methodKlassObj; } 274 static klassOop constMethodKlassObj() { return _constMethodKlassObj; } 275 static klassOop methodDataKlassObj() { return _methodDataKlassObj; } 276 static klassOop klassKlassObj() { return _klassKlassObj; } 277 static klassOop arrayKlassKlassObj() { return _arrayKlassKlassObj; } 278 static klassOop objArrayKlassKlassObj() { return _objArrayKlassKlassObj; } 279 static klassOop typeArrayKlassKlassObj() { return _typeArrayKlassKlassObj; } 280 static klassOop instanceKlassKlassObj() { return _instanceKlassKlassObj; } 281 static klassOop constantPoolKlassObj() { return _constantPoolKlassObj; } 282 static klassOop constantPoolCacheKlassObj() { return _constantPoolCacheKlassObj; } 283 static klassOop compiledICHolderKlassObj() { return _compiledICHolderKlassObj; } 284 static klassOop systemObjArrayKlassObj() { return _systemObjArrayKlassObj; } 285 286 // Known objects in the VM 287 static oop int_mirror() { return check_mirror(_int_mirror); } 288 static oop float_mirror() { return check_mirror(_float_mirror); } 289 static oop double_mirror() { return check_mirror(_double_mirror); } 290 static oop byte_mirror() { return check_mirror(_byte_mirror); } 291 static oop bool_mirror() { return check_mirror(_bool_mirror); } 292 static oop char_mirror() { return check_mirror(_char_mirror); } 293 static oop long_mirror() { return check_mirror(_long_mirror); } 294 static oop short_mirror() { return check_mirror(_short_mirror); } 295 static oop void_mirror() { return check_mirror(_void_mirror); } 296 297 // table of same 298 static oop _mirrors[T_VOID+1]; 299 300 static oop java_mirror(BasicType t) { 301 assert((uint)t < T_VOID+1, "range check"); 302 return check_mirror(_mirrors[t]); 303 } 304 static oop main_thread_group() { return _main_thread_group; } 305 static void set_main_thread_group(oop group) { _main_thread_group = group;} 306 307 static oop system_thread_group() { return _system_thread_group; } 308 static void set_system_thread_group(oop group) { _system_thread_group = group;} 309 310 static typeArrayOop the_empty_byte_array() { return _the_empty_byte_array; } 311 static typeArrayOop the_empty_short_array() { return _the_empty_short_array; } 312 static typeArrayOop the_empty_int_array() { return _the_empty_int_array; } 313 static objArrayOop the_empty_system_obj_array () { return _the_empty_system_obj_array; } 314 static objArrayOop the_empty_class_klass_array () { return _the_empty_class_klass_array; } 315 static objArrayOop the_array_interfaces_array() { return _the_array_interfaces_array; } 316 static oop the_null_string() { return _the_null_string; } 317 static oop the_min_jint_string() { return _the_min_jint_string; } 318 static methodOop finalizer_register_method() { return _finalizer_register_cache->get_methodOop(); } 319 static methodOop loader_addClass_method() { return _loader_addClass_cache->get_methodOop(); } 320 static ActiveMethodOopsCache* reflect_invoke_cache() { return _reflect_invoke_cache; } 321 static oop null_ptr_exception_instance() { return _null_ptr_exception_instance; } 322 static oop arithmetic_exception_instance() { return _arithmetic_exception_instance; } 323 static oop virtual_machine_error_instance() { return _virtual_machine_error_instance; } 324 static oop vm_exception() { return _vm_exception; } 325 326 // OutOfMemoryError support. Returns an error with the required message. The returned error 327 // may or may not have a backtrace. If error has a backtrace then the stack trace is already 328 // filled in. 329 static oop out_of_memory_error_java_heap() { return gen_out_of_memory_error(_out_of_memory_error_java_heap); } 330 static oop out_of_memory_error_perm_gen() { return gen_out_of_memory_error(_out_of_memory_error_perm_gen); } 331 static oop out_of_memory_error_array_size() { return gen_out_of_memory_error(_out_of_memory_error_array_size); } 332 static oop out_of_memory_error_gc_overhead_limit() { return gen_out_of_memory_error(_out_of_memory_error_gc_overhead_limit); } 333 334 // Accessors needed for fast allocation 335 static klassOop* boolArrayKlassObj_addr() { return &_boolArrayKlassObj; } 336 static klassOop* byteArrayKlassObj_addr() { return &_byteArrayKlassObj; } 337 static klassOop* charArrayKlassObj_addr() { return &_charArrayKlassObj; } 338 static klassOop* intArrayKlassObj_addr() { return &_intArrayKlassObj; } 339 static klassOop* shortArrayKlassObj_addr() { return &_shortArrayKlassObj; } 340 static klassOop* longArrayKlassObj_addr() { return &_longArrayKlassObj; } 341 static klassOop* singleArrayKlassObj_addr() { return &_singleArrayKlassObj; } 342 static klassOop* doubleArrayKlassObj_addr() { return &_doubleArrayKlassObj; } 343 static klassOop* systemObjArrayKlassObj_addr() { return &_systemObjArrayKlassObj; } 344 345 // The particular choice of collected heap. 346 static CollectedHeap* heap() { return _collectedHeap; } 347 348 // For UseCompressedOops 349 static address* narrow_oop_base_addr() { return &_narrow_oop._base; } 350 static address narrow_oop_base() { return _narrow_oop._base; } 351 static bool is_narrow_oop_base(void* addr) { return (narrow_oop_base() == (address)addr); } 352 static int narrow_oop_shift() { return _narrow_oop._shift; } 353 static void set_narrow_oop_base(address base) { _narrow_oop._base = base; } 354 static void set_narrow_oop_shift(int shift) { _narrow_oop._shift = shift; } 355 static bool narrow_oop_use_implicit_null_checks() { return _narrow_oop._use_implicit_null_checks; } 356 static void set_narrow_oop_use_implicit_null_checks(bool use) { _narrow_oop._use_implicit_null_checks = use; } 357 // Narrow Oop encoding mode: 358 // 0 - Use 32-bits oops without encoding when 359 // NarrowOopHeapBaseMin + heap_size < 4Gb 360 // 1 - Use zero based compressed oops with encoding when 361 // NarrowOopHeapBaseMin + heap_size < 32Gb 362 // 2 - Use compressed oops with heap base + encoding. 363 enum NARROW_OOP_MODE { 364 UnscaledNarrowOop = 0, 365 ZeroBasedNarrowOop = 1, 366 HeapBasedNarrowOop = 2 367 }; 368 static char* preferred_heap_base(size_t heap_size, NARROW_OOP_MODE mode); 369 370 // Historic gc information 371 static size_t get_heap_capacity_at_last_gc() { return _heap_capacity_at_last_gc; } 372 static size_t get_heap_free_at_last_gc() { return _heap_capacity_at_last_gc - _heap_used_at_last_gc; } 373 static size_t get_heap_used_at_last_gc() { return _heap_used_at_last_gc; } 374 static void update_heap_info_at_gc(); 375 376 // Testers 377 static bool is_bootstrapping() { return _bootstrapping; } 378 static bool is_fully_initialized() { return _fully_initialized; } 379 380 static inline bool element_type_should_be_aligned(BasicType type); 381 static inline bool field_type_should_be_aligned(BasicType type); 382 static bool on_page_boundary(void* addr); 383 static bool should_fill_in_stack_trace(Handle throwable); 384 static void check_alignment(uintx size, uintx alignment, const char* name); 385 386 // Finalizer support. 387 static void run_finalizers_on_exit(); 388 389 // Iteration 390 391 // Apply "f" to the addresses of all the direct heap pointers maintained 392 // as static fields of "Universe". 393 static void oops_do(OopClosure* f, bool do_all = false); 394 395 // Apply "f" to all klasses for basic types (classes not present in 396 // SystemDictionary). 397 static void basic_type_classes_do(void f(klassOop)); 398 399 // Apply "f" to all system klasses (classes not present in SystemDictionary). 400 static void system_classes_do(void f(klassOop)); 401 402 // For sharing -- fill in a list of known vtable pointers. 403 static void init_self_patching_vtbl_list(void** list, int count); 404 405 // Debugging 406 static bool verify_in_progress() { return _verify_in_progress; } 407 static void verify(bool allow_dirty = true, bool silent = false, bool option = true); 408 static int verify_count() { return _verify_count; } 409 static void print(); 410 static void print_on(outputStream* st); 411 static void print_heap_at_SIGBREAK(); 412 static void print_heap_before_gc() { print_heap_before_gc(gclog_or_tty); } 413 static void print_heap_after_gc() { print_heap_after_gc(gclog_or_tty); } 414 static void print_heap_before_gc(outputStream* st); 415 static void print_heap_after_gc(outputStream* st); 416 417 // Change the number of dummy objects kept reachable by the full gc dummy 418 // array; this should trigger relocation in a sliding compaction collector. 419 debug_only(static bool release_fullgc_alot_dummy();) 420 // The non-oop pattern (see compiledIC.hpp, etc) 421 static void* non_oop_word(); 422 423 // Oop verification (see MacroAssembler::verify_oop) 424 static uintptr_t verify_oop_mask() PRODUCT_RETURN0; 425 static uintptr_t verify_oop_bits() PRODUCT_RETURN0; 426 static uintptr_t verify_mark_bits() PRODUCT_RETURN0; 427 static uintptr_t verify_mark_mask() PRODUCT_RETURN0; 428 static uintptr_t verify_klass_mask() PRODUCT_RETURN0; 429 static uintptr_t verify_klass_bits() PRODUCT_RETURN0; 430 431 // Flushing and deoptimization 432 static void flush_dependents_on(instanceKlassHandle dependee); 433#ifdef HOTSWAP 434 // Flushing and deoptimization in case of evolution 435 static void flush_evol_dependents_on(instanceKlassHandle dependee); 436#endif // HOTSWAP 437 // Support for fullspeed debugging 438 static void flush_dependents_on_method(methodHandle dependee); 439 440 // Compiler support 441 static int base_vtable_size() { return _base_vtable_size; } 442}; 443 444class DeferredObjAllocEvent : public CHeapObj { 445 private: 446 oop _oop; 447 size_t _bytesize; 448 jint _arena_id; 449 450 public: 451 DeferredObjAllocEvent(const oop o, const size_t s, const jint id) { 452 _oop = o; 453 _bytesize = s; 454 _arena_id = id; 455 } 456 457 ~DeferredObjAllocEvent() { 458 } 459 460 jint arena_id() { return _arena_id; } 461 size_t bytesize() { return _bytesize; } 462 oop get_oop() { return _oop; } 463}; 464 465#endif // SHARE_VM_MEMORY_UNIVERSE_HPP 466