1 #ifdef USE_PRAGMA_IDENT_HDR
2 #pragma ident "@(#)universe.hpp 1.183 07/08/09 09:12:00 JVM"
3 #endif
4 /*
5 * Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved.
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7 *
8 * This code is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 only, as
10 * published by the Free Software Foundation.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
24 * have any questions.
25 *
26 */
27
28 // Universe is a name space holding known system classes and objects in the VM.
29 //
30 // Loaded classes are accessible through the SystemDictionary.
31 //
32 // The object heap is allocated and accessed through Universe, and various allocation
33 // support is provided. Allocation by the interpreter and compiled code is done inline
34 // and bails out to Scavenge::invoke_and_allocate.
35
36 class CollectedHeap;
37 class DeferredObjAllocEvent;
38
39
40 // Common parts of a methodOop cache. This cache safely interacts with
41 // the RedefineClasses API.
42 //
43 class CommonMethodOopCache : public CHeapObj {
44 // We save the klassOop and the idnum of methodOop in order to get
45 // the current cached methodOop.
46 private:
47 klassOop _klass;
48 int _method_idnum;
49
50 public:
51 CommonMethodOopCache() { _klass = NULL; _method_idnum = -1; }
52 ~CommonMethodOopCache() { _klass = NULL; _method_idnum = -1; }
53
54 void init(klassOop k, methodOop m, TRAPS);
55 klassOop klass() const { return _klass; }
56 int method_idnum() const { return _method_idnum; }
57
58 // GC support
59 void oops_do(OopClosure* f) { f->do_oop((oop*)&_klass); }
60 };
61
62
63 // A helper class for caching a methodOop when the user of the cache
64 // cares about all versions of the methodOop.
65 //
66 class ActiveMethodOopsCache : public CommonMethodOopCache {
67 // This subclass adds weak references to older versions of the
68 // methodOop and a query method for a methodOop.
69
70 private:
71 // If the cached methodOop has not been redefined, then
72 // _prev_methods will be NULL. If all of the previous
73 // versions of the method have been collected, then
74 // _prev_methods can have a length of zero.
75 GrowableArray<jweak>* _prev_methods;
76
77 public:
78 ActiveMethodOopsCache() { _prev_methods = NULL; }
79 ~ActiveMethodOopsCache();
80
81 void add_previous_version(const methodOop method);
82 bool is_same_method(const methodOop method) const;
83 };
84
85
86 // A helper class for caching a methodOop when the user of the cache
87 // only cares about the latest version of the methodOop.
88 //
89 class LatestMethodOopCache : public CommonMethodOopCache {
90 // This subclass adds a getter method for the latest methodOop.
91
92 public:
93 methodOop get_methodOop();
94 };
95
96
97 class Universe: AllStatic {
98 friend class MarkSweep;
99 friend class oopDesc;
100 friend class ClassLoader;
101 friend class Arguments;
102 friend class SystemDictionary;
103 friend class VMStructs;
104 friend class CompactingPermGenGen;
105 friend class VM_PopulateDumpSharedSpace;
106
107 friend jint universe_init();
108 friend void universe2_init();
109 friend bool universe_post_init();
110
111 private:
112 // Known classes in the VM
113 static klassOop _boolArrayKlassObj;
114 static klassOop _byteArrayKlassObj;
115 static klassOop _charArrayKlassObj;
116 static klassOop _intArrayKlassObj;
117 static klassOop _shortArrayKlassObj;
118 static klassOop _longArrayKlassObj;
119 static klassOop _singleArrayKlassObj;
120 static klassOop _doubleArrayKlassObj;
121 static klassOop _typeArrayKlassObjs[T_VOID+1];
122
123 static klassOop _objectArrayKlassObj;
124
125 static klassOop _symbolKlassObj;
126 static klassOop _methodKlassObj;
127 static klassOop _constMethodKlassObj;
128 static klassOop _methodDataKlassObj;
129 static klassOop _klassKlassObj;
130 static klassOop _arrayKlassKlassObj;
131 static klassOop _objArrayKlassKlassObj;
132 static klassOop _typeArrayKlassKlassObj;
133 static klassOop _instanceKlassKlassObj;
134 static klassOop _constantPoolKlassObj;
135 static klassOop _constantPoolCacheKlassObj;
136 static klassOop _compiledICHolderKlassObj;
137 static klassOop _systemObjArrayKlassObj;
138
139 // Known objects in the VM
140
141 // Primitive objects
142 static oop _int_mirror;
143 static oop _float_mirror;
144 static oop _double_mirror;
145 static oop _byte_mirror;
146 static oop _bool_mirror;
147 static oop _char_mirror;
148 static oop _long_mirror;
149 static oop _short_mirror;
150 static oop _void_mirror;
151
152 static oop _main_thread_group; // Reference to the main thread group object
153 static oop _system_thread_group; // Reference to the system thread group object
154
155 static typeArrayOop _the_empty_byte_array; // Canonicalized byte array
156 static typeArrayOop _the_empty_short_array; // Canonicalized short array
157 static typeArrayOop _the_empty_int_array; // Canonicalized int array
158 static objArrayOop _the_empty_system_obj_array; // Canonicalized system obj array
159 static objArrayOop _the_empty_class_klass_array; // Canonicalized obj array of type java.lang.Class
160 static objArrayOop _the_array_interfaces_array; // Canonicalized 2-array of cloneable & serializable klasses
161 static LatestMethodOopCache* _finalizer_register_cache; // static method for registering finalizable objects
162 static LatestMethodOopCache* _loader_addClass_cache; // method for registering loaded classes in class loader vector
163 static ActiveMethodOopsCache* _reflect_invoke_cache; // method for security checks
164 static oop _out_of_memory_error_java_heap; // preallocated error object (no backtrace)
165 static oop _out_of_memory_error_perm_gen; // preallocated error object (no backtrace)
166 static oop _out_of_memory_error_array_size;// preallocated error object (no backtrace)
167 static oop _out_of_memory_error_gc_overhead_limit; // preallocated error object (no backtrace)
168
169 // array of preallocated error objects with backtrace
170 static objArrayOop _preallocated_out_of_memory_error_array;
171
172 // number of preallocated error objects available for use
173 static volatile jint _preallocated_out_of_memory_error_avail_count;
174
175 static oop _null_ptr_exception_instance; // preallocated exception object
176 static oop _arithmetic_exception_instance; // preallocated exception object
177 static oop _virtual_machine_error_instance; // preallocated exception object
178 // The object used as an exception dummy when exceptions are thrown for
179 // the vm thread.
180 static oop _vm_exception;
181
182 static oop _emptySymbol; // Canonical empty string ("") symbol
183
184 // The particular choice of collected heap.
185 static CollectedHeap* _collectedHeap;
186
187 // array of dummy objects used with +FullGCAlot
188 debug_only(static objArrayOop _fullgc_alot_dummy_array;)
189 // index of next entry to clear
190 debug_only(static int _fullgc_alot_dummy_next;)
191
192 // Compiler/dispatch support
193 static int _base_vtable_size; // Java vtbl size of klass Object (in words)
194
195 // Initialization
196 static bool _bootstrapping; // true during genesis
197 static bool _fully_initialized; // true after universe_init and initialize_vtables called
198
199 // the array of preallocated errors with backtraces
200 static objArrayOop preallocated_out_of_memory_errors() { return _preallocated_out_of_memory_error_array; }
201
202 // generate an out of memory error; if possible using an error with preallocated backtrace;
203 // otherwise return the given default error.
204 static oop gen_out_of_memory_error(oop default_err);
205
206 // Historic gc information
207 static size_t _heap_capacity_at_last_gc;
208 static size_t _heap_used_at_last_gc;
209
210 static jint initialize_heap();
211 static void initialize_basic_type_mirrors(TRAPS);
212 static void fixup_mirrors(TRAPS);
213
214 static void reinitialize_vtable_of(KlassHandle h_k, TRAPS);
215 static void reinitialize_itables(TRAPS);
216 static void compute_base_vtable_size(); // compute vtable size of class Object
217
218 static void genesis(TRAPS); // Create the initial world
219
220 // Mirrors for primitive classes (created eagerly)
221 static oop check_mirror(oop m) {
222 assert(m != NULL, "mirror not initialized");
223 return m;
224 }
225
226 // Debugging
227 static int _verify_count; // number of verifies done
228 // True during call to verify(). Should only be set/cleared in verify().
229 static bool _verify_in_progress;
230
231 static void compute_verify_oop_data();
232
233 public:
234 // Known classes in the VM
235 static klassOop boolArrayKlassObj() { return _boolArrayKlassObj; }
236 static klassOop byteArrayKlassObj() { return _byteArrayKlassObj; }
237 static klassOop charArrayKlassObj() { return _charArrayKlassObj; }
238 static klassOop intArrayKlassObj() { return _intArrayKlassObj; }
239 static klassOop shortArrayKlassObj() { return _shortArrayKlassObj; }
240 static klassOop longArrayKlassObj() { return _longArrayKlassObj; }
241 static klassOop singleArrayKlassObj() { return _singleArrayKlassObj; }
242 static klassOop doubleArrayKlassObj() { return _doubleArrayKlassObj; }
243
244 static klassOop objectArrayKlassObj() {
245 return _objectArrayKlassObj;
246 }
247
248 static klassOop typeArrayKlassObj(BasicType t) {
249 assert((uint)t < T_VOID+1, "range check");
250 assert(_typeArrayKlassObjs[t] != NULL, "domain check");
251 return _typeArrayKlassObjs[t];
252 }
253
254 static klassOop symbolKlassObj() { return _symbolKlassObj; }
255 static klassOop methodKlassObj() { return _methodKlassObj; }
256 static klassOop constMethodKlassObj() { return _constMethodKlassObj; }
257 static klassOop methodDataKlassObj() { return _methodDataKlassObj; }
258 static klassOop klassKlassObj() { return _klassKlassObj; }
259 static klassOop arrayKlassKlassObj() { return _arrayKlassKlassObj; }
260 static klassOop objArrayKlassKlassObj() { return _objArrayKlassKlassObj; }
261 static klassOop typeArrayKlassKlassObj() { return _typeArrayKlassKlassObj; }
262 static klassOop instanceKlassKlassObj() { return _instanceKlassKlassObj; }
263 static klassOop constantPoolKlassObj() { return _constantPoolKlassObj; }
264 static klassOop constantPoolCacheKlassObj() { return _constantPoolCacheKlassObj; }
265 static klassOop compiledICHolderKlassObj() { return _compiledICHolderKlassObj; }
266 static klassOop systemObjArrayKlassObj() { return _systemObjArrayKlassObj; }
267
268 // Known objects in tbe VM
269 static oop int_mirror() { return check_mirror(_int_mirror);
270 }
271 static oop float_mirror() { return check_mirror(_float_mirror); }
272 static oop double_mirror() { return check_mirror(_double_mirror); }
273 static oop byte_mirror() { return check_mirror(_byte_mirror); }
274 static oop bool_mirror() { return check_mirror(_bool_mirror); }
275 static oop char_mirror() { return check_mirror(_char_mirror); }
276 static oop long_mirror() { return check_mirror(_long_mirror); }
277 static oop short_mirror() { return check_mirror(_short_mirror); }
278 static oop void_mirror() { return check_mirror(_void_mirror); }
279
280 // table of same
281 static oop _mirrors[T_VOID+1];
282
283 static oop java_mirror(BasicType t) {
284 assert((uint)t < T_VOID+1, "range check");
285 return check_mirror(_mirrors[t]);
286 }
287 static oop main_thread_group() { return _main_thread_group; }
288 static void set_main_thread_group(oop group) { _main_thread_group = group;}
289
290 static oop system_thread_group() { return _system_thread_group; }
291 static void set_system_thread_group(oop group) { _system_thread_group = group;}
292
293 static typeArrayOop the_empty_byte_array() { return _the_empty_byte_array; }
294 static typeArrayOop the_empty_short_array() { return _the_empty_short_array; }
295 static typeArrayOop the_empty_int_array() { return _the_empty_int_array; }
296 static objArrayOop the_empty_system_obj_array () { return _the_empty_system_obj_array; }
297 static objArrayOop the_empty_class_klass_array () { return _the_empty_class_klass_array; }
298 static objArrayOop the_array_interfaces_array() { return _the_array_interfaces_array; }
299 static methodOop finalizer_register_method() { return _finalizer_register_cache->get_methodOop(); }
300 static methodOop loader_addClass_method() { return _loader_addClass_cache->get_methodOop(); }
301 static ActiveMethodOopsCache* reflect_invoke_cache() { return _reflect_invoke_cache; }
302 static oop null_ptr_exception_instance() { return _null_ptr_exception_instance; }
303 static oop arithmetic_exception_instance() { return _arithmetic_exception_instance; }
304 static oop virtual_machine_error_instance() { return _virtual_machine_error_instance; }
305 static oop vm_exception() { return _vm_exception; }
306 static oop emptySymbol() { return _emptySymbol; }
307
308 // OutOfMemoryError support. Returns an error with the required message. The returned error
309 // may or may not have a backtrace. If error has a backtrace then the stack trace is already
310 // filled in.
311 static oop out_of_memory_error_java_heap() { return gen_out_of_memory_error(_out_of_memory_error_java_heap); }
312 static oop out_of_memory_error_perm_gen() { return gen_out_of_memory_error(_out_of_memory_error_perm_gen); }
313 static oop out_of_memory_error_array_size() { return gen_out_of_memory_error(_out_of_memory_error_array_size); }
314 static oop out_of_memory_error_gc_overhead_limit() { return gen_out_of_memory_error(_out_of_memory_error_gc_overhead_limit); }
315
316 // Accessors needed for fast allocation
317 static klassOop* boolArrayKlassObj_addr() { return &_boolArrayKlassObj; }
318 static klassOop* byteArrayKlassObj_addr() { return &_byteArrayKlassObj; }
319 static klassOop* charArrayKlassObj_addr() { return &_charArrayKlassObj; }
320 static klassOop* intArrayKlassObj_addr() { return &_intArrayKlassObj; }
321 static klassOop* shortArrayKlassObj_addr() { return &_shortArrayKlassObj; }
322 static klassOop* longArrayKlassObj_addr() { return &_longArrayKlassObj; }
323 static klassOop* singleArrayKlassObj_addr() { return &_singleArrayKlassObj; }
324 static klassOop* doubleArrayKlassObj_addr() { return &_doubleArrayKlassObj; }
325
326 // The particular choice of collected heap.
327 static CollectedHeap* heap() { return _collectedHeap; }
328
329 // Historic gc information
330 static size_t get_heap_capacity_at_last_gc() { return _heap_capacity_at_last_gc; }
331 static size_t get_heap_free_at_last_gc() { return _heap_capacity_at_last_gc - _heap_used_at_last_gc; }
332 static size_t get_heap_used_at_last_gc() { return _heap_used_at_last_gc; }
333 static void update_heap_info_at_gc();
334
335 // Testers
336 static bool is_bootstrapping() { return _bootstrapping; }
337 static bool is_fully_initialized() { return _fully_initialized; }
338
339 static inline bool element_type_should_be_aligned(BasicType type);
340 static inline bool field_type_should_be_aligned(BasicType type);
341 static bool on_page_boundary(void* addr);
342 static bool should_fill_in_stack_trace(Handle throwable);
343 static void check_alignment(uintx size, uintx alignment, const char* name);
344
345 // Finalizer support.
346 static void run_finalizers_on_exit();
347
348 // Iteration
349
350 // Apply "f" to the addresses of all the direct heap pointers maintained
351 // as static fields of "Universe".
352 static void oops_do(OopClosure* f, bool do_all = false);
353
354 // Apply "f" to all klasses for basic types (classes not present in
355 // SystemDictionary).
356 static void basic_type_classes_do(void f(klassOop));
357
358 // Apply "f" to all system klasses (classes not present in SystemDictionary).
359 static void system_classes_do(void f(klassOop));
360
361 // For sharing -- fill in a list of known vtable pointers.
362 static void init_self_patching_vtbl_list(void** list, int count);
363
364 // Debugging
365 static bool verify_in_progress() { return _verify_in_progress; }
366 static void verify(bool allow_dirty = true, bool silent = false);
367 static int verify_count() { return _verify_count; }
368 static void print();
369 static void print_on(outputStream* st);
370 static void print_heap_at_SIGBREAK();
371 static void print_heap_before_gc() { print_heap_before_gc(gclog_or_tty); }
372 static void print_heap_after_gc() { print_heap_after_gc(gclog_or_tty); }
373 static void print_heap_before_gc(outputStream* st);
374 static void print_heap_after_gc(outputStream* st);
375
376 // Change the number of dummy objects kept reachable by the full gc dummy
377 // array; this should trigger relocation in a sliding compaction collector.
378 debug_only(static bool release_fullgc_alot_dummy();)
379 // The non-oop pattern (see compiledIC.hpp, etc)
380 static void* non_oop_word();
381
382 // Oop verification (see MacroAssembler::verify_oop)
383 static uintptr_t verify_oop_mask() PRODUCT_RETURN0;
384 static uintptr_t verify_oop_bits() PRODUCT_RETURN0;
385 static uintptr_t verify_mark_bits() PRODUCT_RETURN0;
386 static uintptr_t verify_mark_mask() PRODUCT_RETURN0;
387 static uintptr_t verify_klass_mask() PRODUCT_RETURN0;
388 static uintptr_t verify_klass_bits() PRODUCT_RETURN0;
389
390 // Flushing and deoptimization
391 static void flush_dependents_on(instanceKlassHandle dependee);
392 #ifdef HOTSWAP
393 // Flushing and deoptimization in case of evolution
394 static void flush_evol_dependents_on(instanceKlassHandle dependee);
395 #endif // HOTSWAP
396 // Support for fullspeed debugging
397 static void flush_dependents_on_method(methodHandle dependee);
398
399 // Compiler support
400 static int base_vtable_size() { return _base_vtable_size; }
401 };
402
403 class DeferredObjAllocEvent : public CHeapObj {
404 private:
405 oop _oop;
406 size_t _bytesize;
407 jint _arena_id;
408
409 public:
410 DeferredObjAllocEvent(const oop o, const size_t s, const jint id) {
411 _oop = o;
412 _bytesize = s;
413 _arena_id = id;
414 }
415
416 ~DeferredObjAllocEvent() {
417 }
418
419 jint arena_id() { return _arena_id; }
420 size_t bytesize() { return _bytesize; }
421 oop get_oop() { return _oop; }
422 };