1 /*
2 * Copyright (c) 1997, 2012, 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 #include "precompiled.hpp"
26 #include "classfile/classLoader.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/symbolTable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmSymbols.hpp"
31 #include "code/codeCache.hpp"
32 #include "code/dependencies.hpp"
33 #include "gc_interface/collectedHeap.inline.hpp"
34 #include "interpreter/interpreter.hpp"
35 #include "memory/cardTableModRefBS.hpp"
36 #include "memory/filemap.hpp"
37 #include "memory/gcLocker.inline.hpp"
38 #include "memory/genCollectedHeap.hpp"
39 #include "memory/genRemSet.hpp"
40 #include "memory/generation.hpp"
41 #include "memory/oopFactory.hpp"
42 #include "memory/permGen.hpp"
43 #include "memory/space.hpp"
44 #include "memory/universe.hpp"
45 #include "memory/universe.inline.hpp"
46 #include "oops/arrayKlassKlass.hpp"
47 #include "oops/compiledICHolderKlass.hpp"
48 #include "oops/constMethodKlass.hpp"
49 #include "oops/constantPoolKlass.hpp"
50 #include "oops/constantPoolOop.hpp"
51 #include "oops/cpCacheKlass.hpp"
52 #include "oops/cpCacheOop.hpp"
53 #include "oops/instanceKlass.hpp"
54 #include "oops/instanceMirrorKlass.hpp"
55 #include "oops/instanceKlassKlass.hpp"
56 #include "oops/instanceRefKlass.hpp"
57 #include "oops/klassKlass.hpp"
58 #include "oops/klassOop.hpp"
59 #include "oops/methodDataKlass.hpp"
60 #include "oops/methodKlass.hpp"
61 #include "oops/objArrayKlassKlass.hpp"
62 #include "oops/oop.inline.hpp"
63 #include "oops/typeArrayKlass.hpp"
64 #include "oops/typeArrayKlassKlass.hpp"
65 #include "prims/jvmtiRedefineClassesTrace.hpp"
66 #include "runtime/aprofiler.hpp"
67 #include "runtime/arguments.hpp"
68 #include "runtime/deoptimization.hpp"
69 #include "runtime/fprofiler.hpp"
70 #include "runtime/handles.inline.hpp"
71 #include "runtime/init.hpp"
72 #include "runtime/java.hpp"
73 #include "runtime/javaCalls.hpp"
74 #include "runtime/sharedRuntime.hpp"
75 #include "runtime/synchronizer.hpp"
76 #include "runtime/timer.hpp"
77 #include "runtime/vm_operations.hpp"
78 #include "services/memoryService.hpp"
79 #include "utilities/copy.hpp"
80 #include "utilities/events.hpp"
81 #include "utilities/hashtable.inline.hpp"
82 #include "utilities/preserveException.hpp"
83 #ifdef TARGET_OS_FAMILY_linux
84 # include "thread_linux.inline.hpp"
85 #endif
86 #ifdef TARGET_OS_FAMILY_solaris
87 # include "thread_solaris.inline.hpp"
88 #endif
89 #ifdef TARGET_OS_FAMILY_windows
90 # include "thread_windows.inline.hpp"
91 #endif
92 #ifdef TARGET_OS_FAMILY_bsd
93 # include "thread_bsd.inline.hpp"
94 #endif
95 #ifndef SERIALGC
96 #include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp"
97 #include "gc_implementation/concurrentMarkSweep/cmsCollectorPolicy.hpp"
98 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
99 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
100 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
101 #endif
102
103 // Known objects
104 klassOop Universe::_boolArrayKlassObj = NULL;
105 klassOop Universe::_byteArrayKlassObj = NULL;
106 klassOop Universe::_charArrayKlassObj = NULL;
107 klassOop Universe::_intArrayKlassObj = NULL;
108 klassOop Universe::_shortArrayKlassObj = NULL;
109 klassOop Universe::_longArrayKlassObj = NULL;
110 klassOop Universe::_singleArrayKlassObj = NULL;
111 klassOop Universe::_doubleArrayKlassObj = NULL;
112 klassOop Universe::_typeArrayKlassObjs[T_VOID+1] = { NULL /*, NULL...*/ };
113 klassOop Universe::_objectArrayKlassObj = NULL;
114 klassOop Universe::_methodKlassObj = NULL;
115 klassOop Universe::_constMethodKlassObj = NULL;
116 klassOop Universe::_methodDataKlassObj = NULL;
117 klassOop Universe::_klassKlassObj = NULL;
118 klassOop Universe::_arrayKlassKlassObj = NULL;
119 klassOop Universe::_objArrayKlassKlassObj = NULL;
120 klassOop Universe::_typeArrayKlassKlassObj = NULL;
121 klassOop Universe::_instanceKlassKlassObj = NULL;
122 klassOop Universe::_constantPoolKlassObj = NULL;
123 klassOop Universe::_constantPoolCacheKlassObj = NULL;
124 klassOop Universe::_compiledICHolderKlassObj = NULL;
125 klassOop Universe::_systemObjArrayKlassObj = NULL;
126 oop Universe::_int_mirror = NULL;
127 oop Universe::_float_mirror = NULL;
128 oop Universe::_double_mirror = NULL;
129 oop Universe::_byte_mirror = NULL;
130 oop Universe::_bool_mirror = NULL;
131 oop Universe::_char_mirror = NULL;
132 oop Universe::_long_mirror = NULL;
133 oop Universe::_short_mirror = NULL;
134 oop Universe::_void_mirror = NULL;
135 oop Universe::_mirrors[T_VOID+1] = { NULL /*, NULL...*/ };
136 oop Universe::_main_thread_group = NULL;
137 oop Universe::_system_thread_group = NULL;
138 typeArrayOop Universe::_the_empty_byte_array = NULL;
139 typeArrayOop Universe::_the_empty_short_array = NULL;
140 typeArrayOop Universe::_the_empty_int_array = NULL;
141 objArrayOop Universe::_the_empty_system_obj_array = NULL;
142 objArrayOop Universe::_the_empty_class_klass_array = NULL;
143 objArrayOop Universe::_the_array_interfaces_array = NULL;
144 oop Universe::_the_null_string = NULL;
145 oop Universe::_the_min_jint_string = NULL;
146 LatestMethodOopCache* Universe::_finalizer_register_cache = NULL;
147 LatestMethodOopCache* Universe::_loader_addClass_cache = NULL;
148 ActiveMethodOopsCache* Universe::_reflect_invoke_cache = NULL;
149 oop Universe::_out_of_memory_error_java_heap = NULL;
150 oop Universe::_out_of_memory_error_perm_gen = NULL;
151 oop Universe::_out_of_memory_error_array_size = NULL;
152 oop Universe::_out_of_memory_error_gc_overhead_limit = NULL;
153 objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL;
154 volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
155 bool Universe::_verify_in_progress = false;
156 oop Universe::_null_ptr_exception_instance = NULL;
157 oop Universe::_arithmetic_exception_instance = NULL;
158 oop Universe::_virtual_machine_error_instance = NULL;
159 oop Universe::_vm_exception = NULL;
160
161 // These variables are guarded by FullGCALot_lock.
162 debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;)
163 debug_only(int Universe::_fullgc_alot_dummy_next = 0;)
164
165
166 // Heap
167 int Universe::_verify_count = 0;
168
169 int Universe::_base_vtable_size = 0;
170 bool Universe::_bootstrapping = false;
171 bool Universe::_fully_initialized = false;
172
173 size_t Universe::_heap_capacity_at_last_gc;
174 size_t Universe::_heap_used_at_last_gc = 0;
175
176 CollectedHeap* Universe::_collectedHeap = NULL;
177
178 NarrowOopStruct Universe::_narrow_oop = { NULL, 0, true };
179
180
181 void Universe::basic_type_classes_do(void f(klassOop)) {
182 f(boolArrayKlassObj());
183 f(byteArrayKlassObj());
184 f(charArrayKlassObj());
185 f(intArrayKlassObj());
186 f(shortArrayKlassObj());
187 f(longArrayKlassObj());
188 f(singleArrayKlassObj());
189 f(doubleArrayKlassObj());
190 }
191
192
193 void Universe::system_classes_do(void f(klassOop)) {
194 f(methodKlassObj());
195 f(constMethodKlassObj());
196 f(methodDataKlassObj());
197 f(klassKlassObj());
198 f(arrayKlassKlassObj());
199 f(objArrayKlassKlassObj());
200 f(typeArrayKlassKlassObj());
201 f(instanceKlassKlassObj());
202 f(constantPoolKlassObj());
203 f(systemObjArrayKlassObj());
204 }
205
206 void Universe::oops_do(OopClosure* f, bool do_all) {
207
208 f->do_oop((oop*) &_int_mirror);
209 f->do_oop((oop*) &_float_mirror);
210 f->do_oop((oop*) &_double_mirror);
211 f->do_oop((oop*) &_byte_mirror);
212 f->do_oop((oop*) &_bool_mirror);
213 f->do_oop((oop*) &_char_mirror);
214 f->do_oop((oop*) &_long_mirror);
215 f->do_oop((oop*) &_short_mirror);
216 f->do_oop((oop*) &_void_mirror);
217
218 // It's important to iterate over these guys even if they are null,
219 // since that's how shared heaps are restored.
220 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
221 f->do_oop((oop*) &_mirrors[i]);
222 }
223 assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking");
224
225 // %%% Consider moving those "shared oops" over here with the others.
226 f->do_oop((oop*)&_boolArrayKlassObj);
227 f->do_oop((oop*)&_byteArrayKlassObj);
228 f->do_oop((oop*)&_charArrayKlassObj);
229 f->do_oop((oop*)&_intArrayKlassObj);
230 f->do_oop((oop*)&_shortArrayKlassObj);
231 f->do_oop((oop*)&_longArrayKlassObj);
232 f->do_oop((oop*)&_singleArrayKlassObj);
233 f->do_oop((oop*)&_doubleArrayKlassObj);
234 f->do_oop((oop*)&_objectArrayKlassObj);
235 {
236 for (int i = 0; i < T_VOID+1; i++) {
237 if (_typeArrayKlassObjs[i] != NULL) {
238 assert(i >= T_BOOLEAN, "checking");
239 f->do_oop((oop*)&_typeArrayKlassObjs[i]);
240 } else if (do_all) {
241 f->do_oop((oop*)&_typeArrayKlassObjs[i]);
242 }
243 }
244 }
245 f->do_oop((oop*)&_methodKlassObj);
246 f->do_oop((oop*)&_constMethodKlassObj);
247 f->do_oop((oop*)&_methodDataKlassObj);
248 f->do_oop((oop*)&_klassKlassObj);
249 f->do_oop((oop*)&_arrayKlassKlassObj);
250 f->do_oop((oop*)&_objArrayKlassKlassObj);
251 f->do_oop((oop*)&_typeArrayKlassKlassObj);
252 f->do_oop((oop*)&_instanceKlassKlassObj);
253 f->do_oop((oop*)&_constantPoolKlassObj);
254 f->do_oop((oop*)&_constantPoolCacheKlassObj);
255 f->do_oop((oop*)&_compiledICHolderKlassObj);
256 f->do_oop((oop*)&_systemObjArrayKlassObj);
257 f->do_oop((oop*)&_the_empty_byte_array);
258 f->do_oop((oop*)&_the_empty_short_array);
259 f->do_oop((oop*)&_the_empty_int_array);
260 f->do_oop((oop*)&_the_empty_system_obj_array);
261 f->do_oop((oop*)&_the_empty_class_klass_array);
262 f->do_oop((oop*)&_the_array_interfaces_array);
263 f->do_oop((oop*)&_the_null_string);
264 f->do_oop((oop*)&_the_min_jint_string);
265 _finalizer_register_cache->oops_do(f);
266 _loader_addClass_cache->oops_do(f);
267 _reflect_invoke_cache->oops_do(f);
268 f->do_oop((oop*)&_out_of_memory_error_java_heap);
269 f->do_oop((oop*)&_out_of_memory_error_perm_gen);
270 f->do_oop((oop*)&_out_of_memory_error_array_size);
271 f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit);
272 if (_preallocated_out_of_memory_error_array != (oop)NULL) { // NULL when DumpSharedSpaces
273 f->do_oop((oop*)&_preallocated_out_of_memory_error_array);
274 }
275 f->do_oop((oop*)&_null_ptr_exception_instance);
276 f->do_oop((oop*)&_arithmetic_exception_instance);
277 f->do_oop((oop*)&_virtual_machine_error_instance);
278 f->do_oop((oop*)&_main_thread_group);
279 f->do_oop((oop*)&_system_thread_group);
280 f->do_oop((oop*)&_vm_exception);
281 debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);)
282 }
283
284
285 void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
286 if (size < alignment || size % alignment != 0) {
287 ResourceMark rm;
288 stringStream st;
289 st.print("Size of %s (%ld bytes) must be aligned to %ld bytes", name, size, alignment);
290 char* error = st.as_string();
291 vm_exit_during_initialization(error);
292 }
293 }
294
295
296 void Universe::genesis(TRAPS) {
297 ResourceMark rm;
298 { FlagSetting fs(_bootstrapping, true);
299
300 { MutexLocker mc(Compile_lock);
301
302 // determine base vtable size; without that we cannot create the array klasses
303 compute_base_vtable_size();
304
305 if (!UseSharedSpaces) {
306 _klassKlassObj = klassKlass::create_klass(CHECK);
307 _arrayKlassKlassObj = arrayKlassKlass::create_klass(CHECK);
308
309 _objArrayKlassKlassObj = objArrayKlassKlass::create_klass(CHECK);
310 _instanceKlassKlassObj = instanceKlassKlass::create_klass(CHECK);
311 _typeArrayKlassKlassObj = typeArrayKlassKlass::create_klass(CHECK);
312
313 _boolArrayKlassObj = typeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK);
314 _charArrayKlassObj = typeArrayKlass::create_klass(T_CHAR, sizeof(jchar), CHECK);
315 _singleArrayKlassObj = typeArrayKlass::create_klass(T_FLOAT, sizeof(jfloat), CHECK);
316 _doubleArrayKlassObj = typeArrayKlass::create_klass(T_DOUBLE, sizeof(jdouble), CHECK);
317 _byteArrayKlassObj = typeArrayKlass::create_klass(T_BYTE, sizeof(jbyte), CHECK);
318 _shortArrayKlassObj = typeArrayKlass::create_klass(T_SHORT, sizeof(jshort), CHECK);
319 _intArrayKlassObj = typeArrayKlass::create_klass(T_INT, sizeof(jint), CHECK);
320 _longArrayKlassObj = typeArrayKlass::create_klass(T_LONG, sizeof(jlong), CHECK);
321
322 _typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj;
323 _typeArrayKlassObjs[T_CHAR] = _charArrayKlassObj;
324 _typeArrayKlassObjs[T_FLOAT] = _singleArrayKlassObj;
325 _typeArrayKlassObjs[T_DOUBLE] = _doubleArrayKlassObj;
326 _typeArrayKlassObjs[T_BYTE] = _byteArrayKlassObj;
327 _typeArrayKlassObjs[T_SHORT] = _shortArrayKlassObj;
328 _typeArrayKlassObjs[T_INT] = _intArrayKlassObj;
329 _typeArrayKlassObjs[T_LONG] = _longArrayKlassObj;
330
331 _methodKlassObj = methodKlass::create_klass(CHECK);
332 _constMethodKlassObj = constMethodKlass::create_klass(CHECK);
333 _methodDataKlassObj = methodDataKlass::create_klass(CHECK);
334 _constantPoolKlassObj = constantPoolKlass::create_klass(CHECK);
335 _constantPoolCacheKlassObj = constantPoolCacheKlass::create_klass(CHECK);
336
337 _compiledICHolderKlassObj = compiledICHolderKlass::create_klass(CHECK);
338 _systemObjArrayKlassObj = objArrayKlassKlass::cast(objArrayKlassKlassObj())->allocate_system_objArray_klass(CHECK);
339
340 _the_empty_byte_array = oopFactory::new_permanent_byteArray(0, CHECK);
341 _the_empty_short_array = oopFactory::new_permanent_shortArray(0, CHECK);
342 _the_empty_int_array = oopFactory::new_permanent_intArray(0, CHECK);
343 _the_empty_system_obj_array = oopFactory::new_system_objArray(0, CHECK);
344
345 _the_array_interfaces_array = oopFactory::new_system_objArray(2, CHECK);
346 }
347 }
348
349 vmSymbols::initialize(CHECK);
350
351 SystemDictionary::initialize(CHECK);
352
353 klassOop ok = SystemDictionary::Object_klass();
354
355 _the_null_string = StringTable::intern("null", CHECK);
356 _the_min_jint_string = StringTable::intern("-2147483648", CHECK);
357
358 if (UseSharedSpaces) {
359 // Verify shared interfaces array.
360 assert(_the_array_interfaces_array->obj_at(0) ==
361 SystemDictionary::Cloneable_klass(), "u3");
362 assert(_the_array_interfaces_array->obj_at(1) ==
363 SystemDictionary::Serializable_klass(), "u3");
364
365 // Verify element klass for system obj array klass
366 assert(objArrayKlass::cast(_systemObjArrayKlassObj)->element_klass() == ok, "u1");
367 assert(objArrayKlass::cast(_systemObjArrayKlassObj)->bottom_klass() == ok, "u2");
368
369 // Verify super class for the classes created above
370 assert(Klass::cast(boolArrayKlassObj() )->super() == ok, "u3");
371 assert(Klass::cast(charArrayKlassObj() )->super() == ok, "u3");
372 assert(Klass::cast(singleArrayKlassObj() )->super() == ok, "u3");
373 assert(Klass::cast(doubleArrayKlassObj() )->super() == ok, "u3");
374 assert(Klass::cast(byteArrayKlassObj() )->super() == ok, "u3");
375 assert(Klass::cast(shortArrayKlassObj() )->super() == ok, "u3");
376 assert(Klass::cast(intArrayKlassObj() )->super() == ok, "u3");
377 assert(Klass::cast(longArrayKlassObj() )->super() == ok, "u3");
378 assert(Klass::cast(constantPoolKlassObj() )->super() == ok, "u3");
379 assert(Klass::cast(systemObjArrayKlassObj())->super() == ok, "u3");
380 } else {
381 // Set up shared interfaces array. (Do this before supers are set up.)
382 _the_array_interfaces_array->obj_at_put(0, SystemDictionary::Cloneable_klass());
383 _the_array_interfaces_array->obj_at_put(1, SystemDictionary::Serializable_klass());
384
385 // Set element klass for system obj array klass
386 objArrayKlass::cast(_systemObjArrayKlassObj)->set_element_klass(ok);
387 objArrayKlass::cast(_systemObjArrayKlassObj)->set_bottom_klass(ok);
388
389 // Set super class for the classes created above
390 Klass::cast(boolArrayKlassObj() )->initialize_supers(ok, CHECK);
391 Klass::cast(charArrayKlassObj() )->initialize_supers(ok, CHECK);
392 Klass::cast(singleArrayKlassObj() )->initialize_supers(ok, CHECK);
393 Klass::cast(doubleArrayKlassObj() )->initialize_supers(ok, CHECK);
394 Klass::cast(byteArrayKlassObj() )->initialize_supers(ok, CHECK);
395 Klass::cast(shortArrayKlassObj() )->initialize_supers(ok, CHECK);
396 Klass::cast(intArrayKlassObj() )->initialize_supers(ok, CHECK);
397 Klass::cast(longArrayKlassObj() )->initialize_supers(ok, CHECK);
398 Klass::cast(constantPoolKlassObj() )->initialize_supers(ok, CHECK);
399 Klass::cast(systemObjArrayKlassObj())->initialize_supers(ok, CHECK);
400 Klass::cast(boolArrayKlassObj() )->set_super(ok);
401 Klass::cast(charArrayKlassObj() )->set_super(ok);
402 Klass::cast(singleArrayKlassObj() )->set_super(ok);
403 Klass::cast(doubleArrayKlassObj() )->set_super(ok);
404 Klass::cast(byteArrayKlassObj() )->set_super(ok);
405 Klass::cast(shortArrayKlassObj() )->set_super(ok);
406 Klass::cast(intArrayKlassObj() )->set_super(ok);
407 Klass::cast(longArrayKlassObj() )->set_super(ok);
408 Klass::cast(constantPoolKlassObj() )->set_super(ok);
409 Klass::cast(systemObjArrayKlassObj())->set_super(ok);
410 }
411
412 Klass::cast(boolArrayKlassObj() )->append_to_sibling_list();
413 Klass::cast(charArrayKlassObj() )->append_to_sibling_list();
414 Klass::cast(singleArrayKlassObj() )->append_to_sibling_list();
415 Klass::cast(doubleArrayKlassObj() )->append_to_sibling_list();
416 Klass::cast(byteArrayKlassObj() )->append_to_sibling_list();
417 Klass::cast(shortArrayKlassObj() )->append_to_sibling_list();
418 Klass::cast(intArrayKlassObj() )->append_to_sibling_list();
419 Klass::cast(longArrayKlassObj() )->append_to_sibling_list();
420 Klass::cast(constantPoolKlassObj() )->append_to_sibling_list();
421 Klass::cast(systemObjArrayKlassObj())->append_to_sibling_list();
422 } // end of core bootstrapping
423
424 // Initialize _objectArrayKlass after core bootstraping to make
425 // sure the super class is set up properly for _objectArrayKlass.
426 _objectArrayKlassObj = instanceKlass::
427 cast(SystemDictionary::Object_klass())->array_klass(1, CHECK);
428 // Add the class to the class hierarchy manually to make sure that
429 // its vtable is initialized after core bootstrapping is completed.
430 Klass::cast(_objectArrayKlassObj)->append_to_sibling_list();
431
432 // Compute is_jdk version flags.
433 // Only 1.3 or later has the java.lang.Shutdown class.
434 // Only 1.4 or later has the java.lang.CharSequence interface.
435 // Only 1.5 or later has the java.lang.management.MemoryUsage class.
436 if (JDK_Version::is_partially_initialized()) {
437 uint8_t jdk_version;
438 klassOop k = SystemDictionary::resolve_or_null(
439 vmSymbols::java_lang_management_MemoryUsage(), THREAD);
440 CLEAR_PENDING_EXCEPTION; // ignore exceptions
441 if (k == NULL) {
442 k = SystemDictionary::resolve_or_null(
443 vmSymbols::java_lang_CharSequence(), THREAD);
444 CLEAR_PENDING_EXCEPTION; // ignore exceptions
445 if (k == NULL) {
446 k = SystemDictionary::resolve_or_null(
447 vmSymbols::java_lang_Shutdown(), THREAD);
448 CLEAR_PENDING_EXCEPTION; // ignore exceptions
449 if (k == NULL) {
450 jdk_version = 2;
451 } else {
452 jdk_version = 3;
453 }
454 } else {
455 jdk_version = 4;
456 }
457 } else {
458 jdk_version = 5;
459 }
460 JDK_Version::fully_initialize(jdk_version);
461 }
462
463 #ifdef ASSERT
464 if (FullGCALot) {
465 // Allocate an array of dummy objects.
466 // We'd like these to be at the bottom of the old generation,
467 // so that when we free one and then collect,
468 // (almost) the whole heap moves
469 // and we find out if we actually update all the oops correctly.
470 // But we can't allocate directly in the old generation,
471 // so we allocate wherever, and hope that the first collection
472 // moves these objects to the bottom of the old generation.
473 // We can allocate directly in the permanent generation, so we do.
474 int size;
475 if (UseConcMarkSweepGC) {
476 warning("Using +FullGCALot with concurrent mark sweep gc "
477 "will not force all objects to relocate");
478 size = FullGCALotDummies;
479 } else {
480 size = FullGCALotDummies * 2;
481 }
482 objArrayOop naked_array = oopFactory::new_system_objArray(size, CHECK);
483 objArrayHandle dummy_array(THREAD, naked_array);
484 int i = 0;
485 while (i < size) {
486 if (!UseConcMarkSweepGC) {
487 // Allocate dummy in old generation
488 oop dummy = instanceKlass::cast(SystemDictionary::Object_klass())->allocate_instance(CHECK);
489 dummy_array->obj_at_put(i++, dummy);
490 }
491 // Allocate dummy in permanent generation
492 oop dummy = instanceKlass::cast(SystemDictionary::Object_klass())->allocate_permanent_instance(CHECK);
493 dummy_array->obj_at_put(i++, dummy);
494 }
495 {
496 // Only modify the global variable inside the mutex.
497 // If we had a race to here, the other dummy_array instances
498 // and their elements just get dropped on the floor, which is fine.
499 MutexLocker ml(FullGCALot_lock);
500 if (_fullgc_alot_dummy_array == NULL) {
501 _fullgc_alot_dummy_array = dummy_array();
502 }
503 }
504 assert(i == _fullgc_alot_dummy_array->length(), "just checking");
505 }
506 #endif
507 }
508
509
510 static inline void* dereference(void* addr) {
511 return *(void**)addr;
512 }
513
514 static inline void add_vtable(void** list, int* n, void* o, int count) {
515 guarantee((*n) < count, "vtable list too small");
516 void* vtable = dereference(o);
517 assert(dereference(vtable) != NULL, "invalid vtable");
518 list[(*n)++] = vtable;
519 }
520
521 void Universe::init_self_patching_vtbl_list(void** list, int count) {
522 int n = 0;
523 { klassKlass o; add_vtable(list, &n, &o, count); }
524 { arrayKlassKlass o; add_vtable(list, &n, &o, count); }
525 { objArrayKlassKlass o; add_vtable(list, &n, &o, count); }
526 { instanceKlassKlass o; add_vtable(list, &n, &o, count); }
527 { instanceKlass o; add_vtable(list, &n, &o, count); }
528 { instanceMirrorKlass o; add_vtable(list, &n, &o, count); }
529 { instanceRefKlass o; add_vtable(list, &n, &o, count); }
530 { typeArrayKlassKlass o; add_vtable(list, &n, &o, count); }
531 { typeArrayKlass o; add_vtable(list, &n, &o, count); }
532 { methodKlass o; add_vtable(list, &n, &o, count); }
533 { constMethodKlass o; add_vtable(list, &n, &o, count); }
534 { constantPoolKlass o; add_vtable(list, &n, &o, count); }
535 { constantPoolCacheKlass o; add_vtable(list, &n, &o, count); }
536 { objArrayKlass o; add_vtable(list, &n, &o, count); }
537 { methodDataKlass o; add_vtable(list, &n, &o, count); }
538 { compiledICHolderKlass o; add_vtable(list, &n, &o, count); }
539 #ifndef PRODUCT
540 // In non-product builds CHeapObj is derived from AllocatedObj,
541 // so symbols in CDS archive should have their vtable pointer patched.
542 { Symbol o; add_vtable(list, &n, &o, count); }
543 #endif
544 }
545
546
547 class FixupMirrorClosure: public ObjectClosure {
548 public:
549 virtual void do_object(oop obj) {
550 if (obj->is_klass()) {
551 EXCEPTION_MARK;
552 KlassHandle k(THREAD, klassOop(obj));
553 // We will never reach the CATCH below since Exceptions::_throw will cause
554 // the VM to exit if an exception is thrown during initialization
555 java_lang_Class::fixup_mirror(k, CATCH);
556 // This call unconditionally creates a new mirror for k,
557 // and links in k's component_mirror field if k is an array.
558 // If k is an objArray, k's element type must already have
559 // a mirror. In other words, this closure must process
560 // the component type of an objArray k before it processes k.
561 // This works because the permgen iterator presents arrays
562 // and their component types in order of creation.
563 }
564 }
565 };
566
567 void Universe::initialize_basic_type_mirrors(TRAPS) {
568 if (UseSharedSpaces) {
569 assert(_int_mirror != NULL, "already loaded");
570 assert(_void_mirror == _mirrors[T_VOID], "consistently loaded");
571 } else {
572
573 assert(_int_mirror==NULL, "basic type mirrors already initialized");
574 _int_mirror =
575 java_lang_Class::create_basic_type_mirror("int", T_INT, CHECK);
576 _float_mirror =
577 java_lang_Class::create_basic_type_mirror("float", T_FLOAT, CHECK);
578 _double_mirror =
579 java_lang_Class::create_basic_type_mirror("double", T_DOUBLE, CHECK);
580 _byte_mirror =
581 java_lang_Class::create_basic_type_mirror("byte", T_BYTE, CHECK);
582 _bool_mirror =
583 java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK);
584 _char_mirror =
585 java_lang_Class::create_basic_type_mirror("char", T_CHAR, CHECK);
586 _long_mirror =
587 java_lang_Class::create_basic_type_mirror("long", T_LONG, CHECK);
588 _short_mirror =
589 java_lang_Class::create_basic_type_mirror("short", T_SHORT, CHECK);
590 _void_mirror =
591 java_lang_Class::create_basic_type_mirror("void", T_VOID, CHECK);
592
593 _mirrors[T_INT] = _int_mirror;
594 _mirrors[T_FLOAT] = _float_mirror;
595 _mirrors[T_DOUBLE] = _double_mirror;
596 _mirrors[T_BYTE] = _byte_mirror;
597 _mirrors[T_BOOLEAN] = _bool_mirror;
598 _mirrors[T_CHAR] = _char_mirror;
599 _mirrors[T_LONG] = _long_mirror;
600 _mirrors[T_SHORT] = _short_mirror;
601 _mirrors[T_VOID] = _void_mirror;
602 //_mirrors[T_OBJECT] = instanceKlass::cast(_object_klass)->java_mirror();
603 //_mirrors[T_ARRAY] = instanceKlass::cast(_object_klass)->java_mirror();
604 }
605 }
606
607 void Universe::fixup_mirrors(TRAPS) {
608 // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly,
609 // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply
610 // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note
611 // that the number of objects allocated at this point is very small.
612 assert(SystemDictionary::Class_klass_loaded(), "java.lang.Class should be loaded");
613
614 // Cache the start of the static fields
615 instanceMirrorKlass::init_offset_of_static_fields();
616
617 FixupMirrorClosure blk;
618 Universe::heap()->permanent_object_iterate(&blk);
619 }
620
621
622 static bool has_run_finalizers_on_exit = false;
623
624 void Universe::run_finalizers_on_exit() {
625 if (has_run_finalizers_on_exit) return;
626 has_run_finalizers_on_exit = true;
627
628 // Called on VM exit. This ought to be run in a separate thread.
629 if (TraceReferenceGC) tty->print_cr("Callback to run finalizers on exit");
630 {
631 PRESERVE_EXCEPTION_MARK;
632 KlassHandle finalizer_klass(THREAD, SystemDictionary::Finalizer_klass());
633 JavaValue result(T_VOID);
634 JavaCalls::call_static(
635 &result,
636 finalizer_klass,
637 vmSymbols::run_finalizers_on_exit_name(),
638 vmSymbols::void_method_signature(),
639 THREAD
640 );
641 // Ignore any pending exceptions
642 CLEAR_PENDING_EXCEPTION;
643 }
644 }
645
646
647 // initialize_vtable could cause gc if
648 // 1) we specified true to initialize_vtable and
649 // 2) this ran after gc was enabled
650 // In case those ever change we use handles for oops
651 void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) {
652 // init vtable of k and all subclasses
653 Klass* ko = k_h()->klass_part();
654 klassVtable* vt = ko->vtable();
655 if (vt) vt->initialize_vtable(false, CHECK);
656 if (ko->oop_is_instance()) {
657 instanceKlass* ik = (instanceKlass*)ko;
658 for (KlassHandle s_h(THREAD, ik->subklass()); s_h() != NULL; s_h = (THREAD, s_h()->klass_part()->next_sibling())) {
659 reinitialize_vtable_of(s_h, CHECK);
660 }
661 }
662 }
663
664
665 void initialize_itable_for_klass(klassOop k, TRAPS) {
666 instanceKlass::cast(k)->itable()->initialize_itable(false, CHECK);
667 }
668
669
670 void Universe::reinitialize_itables(TRAPS) {
671 SystemDictionary::classes_do(initialize_itable_for_klass, CHECK);
672
673 }
674
675
676 bool Universe::on_page_boundary(void* addr) {
677 return ((uintptr_t) addr) % os::vm_page_size() == 0;
678 }
679
680
681 bool Universe::should_fill_in_stack_trace(Handle throwable) {
682 // never attempt to fill in the stack trace of preallocated errors that do not have
683 // backtrace. These errors are kept alive forever and may be "re-used" when all
684 // preallocated errors with backtrace have been consumed. Also need to avoid
685 // a potential loop which could happen if an out of memory occurs when attempting
686 // to allocate the backtrace.
687 return ((throwable() != Universe::_out_of_memory_error_java_heap) &&
688 (throwable() != Universe::_out_of_memory_error_perm_gen) &&
689 (throwable() != Universe::_out_of_memory_error_array_size) &&
690 (throwable() != Universe::_out_of_memory_error_gc_overhead_limit));
691 }
692
693
694 oop Universe::gen_out_of_memory_error(oop default_err) {
695 // generate an out of memory error:
696 // - if there is a preallocated error with backtrace available then return it wth
697 // a filled in stack trace.
698 // - if there are no preallocated errors with backtrace available then return
699 // an error without backtrace.
700 int next;
701 if (_preallocated_out_of_memory_error_avail_count > 0) {
702 next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count);
703 assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt");
704 } else {
705 next = -1;
706 }
707 if (next < 0) {
708 // all preallocated errors have been used.
709 // return default
710 return default_err;
711 } else {
712 // get the error object at the slot and set set it to NULL so that the
713 // array isn't keeping it alive anymore.
714 oop exc = preallocated_out_of_memory_errors()->obj_at(next);
715 assert(exc != NULL, "slot has been used already");
716 preallocated_out_of_memory_errors()->obj_at_put(next, NULL);
717
718 // use the message from the default error
719 oop msg = java_lang_Throwable::message(default_err);
720 assert(msg != NULL, "no message");
721 java_lang_Throwable::set_message(exc, msg);
722
723 // populate the stack trace and return it.
724 java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc);
725 return exc;
726 }
727 }
728
729 static intptr_t non_oop_bits = 0;
730
731 void* Universe::non_oop_word() {
732 // Neither the high bits nor the low bits of this value is allowed
733 // to look like (respectively) the high or low bits of a real oop.
734 //
735 // High and low are CPU-specific notions, but low always includes
736 // the low-order bit. Since oops are always aligned at least mod 4,
737 // setting the low-order bit will ensure that the low half of the
738 // word will never look like that of a real oop.
739 //
740 // Using the OS-supplied non-memory-address word (usually 0 or -1)
741 // will take care of the high bits, however many there are.
742
743 if (non_oop_bits == 0) {
744 non_oop_bits = (intptr_t)os::non_memory_address_word() | 1;
745 }
746
747 return (void*)non_oop_bits;
748 }
749
750 jint universe_init() {
751 assert(!Universe::_fully_initialized, "called after initialize_vtables");
752 guarantee(1 << LogHeapWordSize == sizeof(HeapWord),
753 "LogHeapWordSize is incorrect.");
754 guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?");
755 guarantee(sizeof(oop) % sizeof(HeapWord) == 0,
756 "oop size is not not a multiple of HeapWord size");
757 TraceTime timer("Genesis", TraceStartupTime);
758 GC_locker::lock(); // do not allow gc during bootstrapping
759 JavaClasses::compute_hard_coded_offsets();
760
761 // Get map info from shared archive file.
762 if (DumpSharedSpaces)
763 UseSharedSpaces = false;
764
765 FileMapInfo* mapinfo = NULL;
766 if (UseSharedSpaces) {
767 mapinfo = NEW_C_HEAP_OBJ(FileMapInfo, mtInternal);
768 memset(mapinfo, 0, sizeof(FileMapInfo));
769
770 // Open the shared archive file, read and validate the header. If
771 // initialization files, shared spaces [UseSharedSpaces] are
772 // disabled and the file is closed.
773
774 if (mapinfo->initialize()) {
775 FileMapInfo::set_current_info(mapinfo);
776 } else {
777 assert(!mapinfo->is_open() && !UseSharedSpaces,
778 "archive file not closed or shared spaces not disabled.");
779 }
780 }
781
782 jint status = Universe::initialize_heap();
783 if (status != JNI_OK) {
784 return status;
785 }
786
787 // We have a heap so create the methodOop caches before
788 // CompactingPermGenGen::initialize_oops() tries to populate them.
789 Universe::_finalizer_register_cache = new LatestMethodOopCache();
790 Universe::_loader_addClass_cache = new LatestMethodOopCache();
791 Universe::_reflect_invoke_cache = new ActiveMethodOopsCache();
792
793 if (UseSharedSpaces) {
794
795 // Read the data structures supporting the shared spaces (shared
796 // system dictionary, symbol table, etc.). After that, access to
797 // the file (other than the mapped regions) is no longer needed, and
798 // the file is closed. Closing the file does not affect the
799 // currently mapped regions.
800
801 CompactingPermGenGen::initialize_oops();
802 mapinfo->close();
803
804 } else {
805 SymbolTable::create_table();
806 StringTable::create_table();
807 ClassLoader::create_package_info_table();
808 }
809
810 return JNI_OK;
811 }
812
813 // Choose the heap base address and oop encoding mode
814 // when compressed oops are used:
815 // Unscaled - Use 32-bits oops without encoding when
816 // NarrowOopHeapBaseMin + heap_size < 4Gb
817 // ZeroBased - Use zero based compressed oops with encoding when
818 // NarrowOopHeapBaseMin + heap_size < 32Gb
819 // HeapBased - Use compressed oops with heap base + encoding.
820
821 // 4Gb
822 static const uint64_t NarrowOopHeapMax = (uint64_t(max_juint) + 1);
823 // 32Gb
824 // OopEncodingHeapMax == NarrowOopHeapMax << LogMinObjAlignmentInBytes;
825
826 char* Universe::preferred_heap_base(size_t heap_size, NARROW_OOP_MODE mode) {
827 size_t base = 0;
828 #ifdef _LP64
829 if (UseCompressedOops) {
830 assert(mode == UnscaledNarrowOop ||
831 mode == ZeroBasedNarrowOop ||
832 mode == HeapBasedNarrowOop, "mode is invalid");
833 const size_t total_size = heap_size + HeapBaseMinAddress;
834 // Return specified base for the first request.
835 if (!FLAG_IS_DEFAULT(HeapBaseMinAddress) && (mode == UnscaledNarrowOop)) {
836 base = HeapBaseMinAddress;
837 } else if (total_size <= OopEncodingHeapMax && (mode != HeapBasedNarrowOop)) {
838 if (total_size <= NarrowOopHeapMax && (mode == UnscaledNarrowOop) &&
839 (Universe::narrow_oop_shift() == 0)) {
840 // Use 32-bits oops without encoding and
841 // place heap's top on the 4Gb boundary
842 base = (NarrowOopHeapMax - heap_size);
843 } else {
844 // Can't reserve with NarrowOopShift == 0
845 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
846 if (mode == UnscaledNarrowOop ||
847 mode == ZeroBasedNarrowOop && total_size <= NarrowOopHeapMax) {
848 // Use zero based compressed oops with encoding and
849 // place heap's top on the 32Gb boundary in case
850 // total_size > 4Gb or failed to reserve below 4Gb.
851 base = (OopEncodingHeapMax - heap_size);
852 }
853 }
854 } else {
855 // Can't reserve below 32Gb.
856 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
857 }
858 // Set narrow_oop_base and narrow_oop_use_implicit_null_checks
859 // used in ReservedHeapSpace() constructors.
860 // The final values will be set in initialize_heap() below.
861 if (base != 0 && (base + heap_size) <= OopEncodingHeapMax) {
862 // Use zero based compressed oops
863 Universe::set_narrow_oop_base(NULL);
864 // Don't need guard page for implicit checks in indexed
865 // addressing mode with zero based Compressed Oops.
866 Universe::set_narrow_oop_use_implicit_null_checks(true);
867 } else {
868 // Set to a non-NULL value so the ReservedSpace ctor computes
869 // the correct no-access prefix.
870 // The final value will be set in initialize_heap() below.
871 Universe::set_narrow_oop_base((address)NarrowOopHeapMax);
872 #ifdef _WIN64
873 if (UseLargePages) {
874 // Cannot allocate guard pages for implicit checks in indexed
875 // addressing mode when large pages are specified on windows.
876 Universe::set_narrow_oop_use_implicit_null_checks(false);
877 }
878 #endif // _WIN64
879 }
880 }
881 #endif
882 return (char*)base; // also return NULL (don't care) for 32-bit VM
883 }
884
885 jint Universe::initialize_heap() {
886
887 if (UseParallelGC) {
888 #ifndef SERIALGC
889 Universe::_collectedHeap = new ParallelScavengeHeap();
890 #else // SERIALGC
891 fatal("UseParallelGC not supported in java kernel vm.");
892 #endif // SERIALGC
893
894 } else if (UseG1GC) {
895 #ifndef SERIALGC
896 G1CollectorPolicy* g1p = new G1CollectorPolicy();
897 G1CollectedHeap* g1h = new G1CollectedHeap(g1p);
898 Universe::_collectedHeap = g1h;
899 #else // SERIALGC
900 fatal("UseG1GC not supported in java kernel vm.");
901 #endif // SERIALGC
902
903 } else {
904 GenCollectorPolicy *gc_policy;
905
906 if (UseSerialGC) {
907 gc_policy = new MarkSweepPolicy();
908 } else if (UseConcMarkSweepGC) {
909 #ifndef SERIALGC
910 if (UseAdaptiveSizePolicy) {
911 gc_policy = new ASConcurrentMarkSweepPolicy();
912 } else {
913 gc_policy = new ConcurrentMarkSweepPolicy();
914 }
915 #else // SERIALGC
916 fatal("UseConcMarkSweepGC not supported in java kernel vm.");
917 #endif // SERIALGC
918 } else { // default old generation
919 gc_policy = new MarkSweepPolicy();
920 }
921
922 Universe::_collectedHeap = new GenCollectedHeap(gc_policy);
923 }
924
925 jint status = Universe::heap()->initialize();
926 if (status != JNI_OK) {
927 return status;
928 }
929
930 #ifdef _LP64
931 if (UseCompressedOops) {
932 // Subtract a page because something can get allocated at heap base.
933 // This also makes implicit null checking work, because the
934 // memory+1 page below heap_base needs to cause a signal.
935 // See needs_explicit_null_check.
936 // Only set the heap base for compressed oops because it indicates
937 // compressed oops for pstack code.
938 bool verbose = PrintCompressedOopsMode || (PrintMiscellaneous && Verbose);
939 if (verbose) {
940 tty->cr();
941 tty->print("heap address: " PTR_FORMAT ", size: " SIZE_FORMAT " MB",
942 Universe::heap()->base(), Universe::heap()->reserved_region().byte_size()/M);
943 }
944 if ((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax) {
945 // Can't reserve heap below 32Gb.
946 Universe::set_narrow_oop_base(Universe::heap()->base() - os::vm_page_size());
947 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
948 if (verbose) {
949 tty->print(", %s: "PTR_FORMAT,
950 narrow_oop_mode_to_string(HeapBasedNarrowOop),
951 Universe::narrow_oop_base());
952 }
953 } else {
954 Universe::set_narrow_oop_base(0);
955 if (verbose) {
956 tty->print(", %s", narrow_oop_mode_to_string(ZeroBasedNarrowOop));
957 }
958 #ifdef _WIN64
959 if (!Universe::narrow_oop_use_implicit_null_checks()) {
960 // Don't need guard page for implicit checks in indexed addressing
961 // mode with zero based Compressed Oops.
962 Universe::set_narrow_oop_use_implicit_null_checks(true);
963 }
964 #endif // _WIN64
965 if((uint64_t)Universe::heap()->reserved_region().end() > NarrowOopHeapMax) {
966 // Can't reserve heap below 4Gb.
967 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
968 } else {
969 Universe::set_narrow_oop_shift(0);
970 if (verbose) {
971 tty->print(", %s", narrow_oop_mode_to_string(UnscaledNarrowOop));
972 }
973 }
974 }
975 if (verbose) {
976 tty->cr();
977 tty->cr();
978 }
979 }
980 assert(Universe::narrow_oop_base() == (Universe::heap()->base() - os::vm_page_size()) ||
981 Universe::narrow_oop_base() == NULL, "invalid value");
982 assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes ||
983 Universe::narrow_oop_shift() == 0, "invalid value");
984 #endif
985
986 // We will never reach the CATCH below since Exceptions::_throw will cause
987 // the VM to exit if an exception is thrown during initialization
988
989 if (UseTLAB) {
990 assert(Universe::heap()->supports_tlab_allocation(),
991 "Should support thread-local allocation buffers");
992 ThreadLocalAllocBuffer::startup_initialization();
993 }
994 return JNI_OK;
995 }
996
997 // It's the caller's repsonsibility to ensure glitch-freedom
998 // (if required).
999 void Universe::update_heap_info_at_gc() {
1000 _heap_capacity_at_last_gc = heap()->capacity();
1001 _heap_used_at_last_gc = heap()->used();
1002 }
1003
1004
1005 const char* Universe::narrow_oop_mode_to_string(Universe::NARROW_OOP_MODE mode) {
1006 switch (mode) {
1007 case UnscaledNarrowOop:
1008 return "32-bits Oops";
1009 case ZeroBasedNarrowOop:
1010 return "zero based Compressed Oops";
1011 case HeapBasedNarrowOop:
1012 return "Compressed Oops with base";
1013 }
1014
1015 ShouldNotReachHere();
1016 return "";
1017 }
1018
1019
1020 Universe::NARROW_OOP_MODE Universe::narrow_oop_mode() {
1021 if (narrow_oop_base() != 0) {
1022 return HeapBasedNarrowOop;
1023 }
1024
1025 if (narrow_oop_shift() != 0) {
1026 return ZeroBasedNarrowOop;
1027 }
1028
1029 return UnscaledNarrowOop;
1030 }
1031
1032
1033 void universe2_init() {
1034 EXCEPTION_MARK;
1035 Universe::genesis(CATCH);
1036 }
1037
1038
1039 // This function is defined in JVM.cpp
1040 extern void initialize_converter_functions();
1041
1042 bool universe_post_init() {
1043 assert(!is_init_completed(), "Error: initialization not yet completed!");
1044 Universe::_fully_initialized = true;
1045 EXCEPTION_MARK;
1046 { ResourceMark rm;
1047 Interpreter::initialize(); // needed for interpreter entry points
1048 if (!UseSharedSpaces) {
1049 KlassHandle ok_h(THREAD, SystemDictionary::Object_klass());
1050 Universe::reinitialize_vtable_of(ok_h, CHECK_false);
1051 Universe::reinitialize_itables(CHECK_false);
1052 }
1053 }
1054
1055 klassOop k;
1056 instanceKlassHandle k_h;
1057 if (!UseSharedSpaces) {
1058 // Setup preallocated empty java.lang.Class array
1059 Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_false);
1060 // Setup preallocated OutOfMemoryError errors
1061 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_OutOfMemoryError(), true, CHECK_false);
1062 k_h = instanceKlassHandle(THREAD, k);
1063 Universe::_out_of_memory_error_java_heap = k_h->allocate_permanent_instance(CHECK_false);
1064 Universe::_out_of_memory_error_perm_gen = k_h->allocate_permanent_instance(CHECK_false);
1065 Universe::_out_of_memory_error_array_size = k_h->allocate_permanent_instance(CHECK_false);
1066 Universe::_out_of_memory_error_gc_overhead_limit =
1067 k_h->allocate_permanent_instance(CHECK_false);
1068
1069 // Setup preallocated NullPointerException
1070 // (this is currently used for a cheap & dirty solution in compiler exception handling)
1071 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_NullPointerException(), true, CHECK_false);
1072 Universe::_null_ptr_exception_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false);
1073 // Setup preallocated ArithmeticException
1074 // (this is currently used for a cheap & dirty solution in compiler exception handling)
1075 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ArithmeticException(), true, CHECK_false);
1076 Universe::_arithmetic_exception_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false);
1077 // Virtual Machine Error for when we get into a situation we can't resolve
1078 k = SystemDictionary::resolve_or_fail(
1079 vmSymbols::java_lang_VirtualMachineError(), true, CHECK_false);
1080 bool linked = instanceKlass::cast(k)->link_class_or_fail(CHECK_false);
1081 if (!linked) {
1082 tty->print_cr("Unable to link/verify VirtualMachineError class");
1083 return false; // initialization failed
1084 }
1085 Universe::_virtual_machine_error_instance =
1086 instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false);
1087
1088 Universe::_vm_exception = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false);
1089
1090 }
1091 if (!DumpSharedSpaces) {
1092 // These are the only Java fields that are currently set during shared space dumping.
1093 // We prefer to not handle this generally, so we always reinitialize these detail messages.
1094 Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false);
1095 java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg());
1096
1097 msg = java_lang_String::create_from_str("PermGen space", CHECK_false);
1098 java_lang_Throwable::set_message(Universe::_out_of_memory_error_perm_gen, msg());
1099
1100 msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false);
1101 java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg());
1102
1103 msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false);
1104 java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg());
1105
1106 msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
1107 java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg());
1108
1109 // Setup the array of errors that have preallocated backtrace
1110 k = Universe::_out_of_memory_error_java_heap->klass();
1111 assert(k->klass_part()->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error");
1112 k_h = instanceKlassHandle(THREAD, k);
1113
1114 int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
1115 Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false);
1116 for (int i=0; i<len; i++) {
1117 oop err = k_h->allocate_permanent_instance(CHECK_false);
1118 Handle err_h = Handle(THREAD, err);
1119 java_lang_Throwable::allocate_backtrace(err_h, CHECK_false);
1120 Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h());
1121 }
1122 Universe::_preallocated_out_of_memory_error_avail_count = (jint)len;
1123 }
1124
1125
1126 // Setup static method for registering finalizers
1127 // The finalizer klass must be linked before looking up the method, in
1128 // case it needs to get rewritten.
1129 instanceKlass::cast(SystemDictionary::Finalizer_klass())->link_class(CHECK_false);
1130 methodOop m = instanceKlass::cast(SystemDictionary::Finalizer_klass())->find_method(
1131 vmSymbols::register_method_name(),
1132 vmSymbols::register_method_signature());
1133 if (m == NULL || !m->is_static()) {
1134 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
1135 "java.lang.ref.Finalizer.register", false);
1136 }
1137 Universe::_finalizer_register_cache->init(
1138 SystemDictionary::Finalizer_klass(), m, CHECK_false);
1139
1140 // Resolve on first use and initialize class.
1141 // Note: No race-condition here, since a resolve will always return the same result
1142
1143 // Setup method for security checks
1144 k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_reflect_Method(), true, CHECK_false);
1145 k_h = instanceKlassHandle(THREAD, k);
1146 k_h->link_class(CHECK_false);
1147 m = k_h->find_method(vmSymbols::invoke_name(), vmSymbols::object_object_array_object_signature());
1148 if (m == NULL || m->is_static()) {
1149 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
1150 "java.lang.reflect.Method.invoke", false);
1151 }
1152 Universe::_reflect_invoke_cache->init(k_h(), m, CHECK_false);
1153
1154 // Setup method for registering loaded classes in class loader vector
1155 instanceKlass::cast(SystemDictionary::ClassLoader_klass())->link_class(CHECK_false);
1156 m = instanceKlass::cast(SystemDictionary::ClassLoader_klass())->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature());
1157 if (m == NULL || m->is_static()) {
1158 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
1159 "java.lang.ClassLoader.addClass", false);
1160 }
1161 Universe::_loader_addClass_cache->init(
1162 SystemDictionary::ClassLoader_klass(), m, CHECK_false);
1163
1164 // The folowing is initializing converter functions for serialization in
1165 // JVM.cpp. If we clean up the StrictMath code above we may want to find
1166 // a better solution for this as well.
1167 initialize_converter_functions();
1168
1169 // This needs to be done before the first scavenge/gc, since
1170 // it's an input to soft ref clearing policy.
1171 {
1172 MutexLocker x(Heap_lock);
1173 Universe::update_heap_info_at_gc();
1174 }
1175
1176 // ("weak") refs processing infrastructure initialization
1177 Universe::heap()->post_initialize();
1178
1179 GC_locker::unlock(); // allow gc after bootstrapping
1180
1181 MemoryService::set_universe_heap(Universe::_collectedHeap);
1182 return true;
1183 }
1184
1185
1186 void Universe::compute_base_vtable_size() {
1187 _base_vtable_size = ClassLoader::compute_Object_vtable();
1188 }
1189
1190
1191 // %%% The Universe::flush_foo methods belong in CodeCache.
1192
1193 // Flushes compiled methods dependent on dependee.
1194 void Universe::flush_dependents_on(instanceKlassHandle dependee) {
1195 assert_lock_strong(Compile_lock);
1196
1197 if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
1198
1199 // CodeCache can only be updated by a thread_in_VM and they will all be
1200 // stopped dring the safepoint so CodeCache will be safe to update without
1201 // holding the CodeCache_lock.
1202
1203 KlassDepChange changes(dependee);
1204
1205 // Compute the dependent nmethods
1206 if (CodeCache::mark_for_deoptimization(changes) > 0) {
1207 // At least one nmethod has been marked for deoptimization
1208 VM_Deoptimize op;
1209 VMThread::execute(&op);
1210 }
1211 }
1212
1213 // Flushes compiled methods dependent on a particular CallSite
1214 // instance when its target is different than the given MethodHandle.
1215 void Universe::flush_dependents_on(Handle call_site, Handle method_handle) {
1216 assert_lock_strong(Compile_lock);
1217
1218 if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
1219
1220 // CodeCache can only be updated by a thread_in_VM and they will all be
1221 // stopped dring the safepoint so CodeCache will be safe to update without
1222 // holding the CodeCache_lock.
1223
1224 CallSiteDepChange changes(call_site(), method_handle());
1225
1226 // Compute the dependent nmethods that have a reference to a
1227 // CallSite object. We use instanceKlass::mark_dependent_nmethod
1228 // directly instead of CodeCache::mark_for_deoptimization because we
1229 // want dependents on the call site class only not all classes in
1230 // the ContextStream.
1231 int marked = 0;
1232 {
1233 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1234 instanceKlass* call_site_klass = instanceKlass::cast(call_site->klass());
1235 marked = call_site_klass->mark_dependent_nmethods(changes);
1236 }
1237 if (marked > 0) {
1238 // At least one nmethod has been marked for deoptimization
1239 VM_Deoptimize op;
1240 VMThread::execute(&op);
1241 }
1242 }
1243
1244 #ifdef HOTSWAP
1245 // Flushes compiled methods dependent on dependee in the evolutionary sense
1246 void Universe::flush_evol_dependents_on(instanceKlassHandle ev_k_h) {
1247 // --- Compile_lock is not held. However we are at a safepoint.
1248 assert_locked_or_safepoint(Compile_lock);
1249 if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
1250
1251 // CodeCache can only be updated by a thread_in_VM and they will all be
1252 // stopped dring the safepoint so CodeCache will be safe to update without
1253 // holding the CodeCache_lock.
1254
1255 // Compute the dependent nmethods
1256 if (CodeCache::mark_for_evol_deoptimization(ev_k_h) > 0) {
1257 // At least one nmethod has been marked for deoptimization
1258
1259 // All this already happens inside a VM_Operation, so we'll do all the work here.
1260 // Stuff copied from VM_Deoptimize and modified slightly.
1261
1262 // We do not want any GCs to happen while we are in the middle of this VM operation
1263 ResourceMark rm;
1264 DeoptimizationMarker dm;
1265
1266 // Deoptimize all activations depending on marked nmethods
1267 Deoptimization::deoptimize_dependents();
1268
1269 // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
1270 CodeCache::make_marked_nmethods_not_entrant();
1271 }
1272 }
1273 #endif // HOTSWAP
1274
1275
1276 // Flushes compiled methods dependent on dependee
1277 void Universe::flush_dependents_on_method(methodHandle m_h) {
1278 // --- Compile_lock is not held. However we are at a safepoint.
1279 assert_locked_or_safepoint(Compile_lock);
1280
1281 // CodeCache can only be updated by a thread_in_VM and they will all be
1282 // stopped dring the safepoint so CodeCache will be safe to update without
1283 // holding the CodeCache_lock.
1284
1285 // Compute the dependent nmethods
1286 if (CodeCache::mark_for_deoptimization(m_h()) > 0) {
1287 // At least one nmethod has been marked for deoptimization
1288
1289 // All this already happens inside a VM_Operation, so we'll do all the work here.
1290 // Stuff copied from VM_Deoptimize and modified slightly.
1291
1292 // We do not want any GCs to happen while we are in the middle of this VM operation
1293 ResourceMark rm;
1294 DeoptimizationMarker dm;
1295
1296 // Deoptimize all activations depending on marked nmethods
1297 Deoptimization::deoptimize_dependents();
1298
1299 // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
1300 CodeCache::make_marked_nmethods_not_entrant();
1301 }
1302 }
1303
1304 void Universe::print() {
1305 print_on(gclog_or_tty);
1306 }
1307
1308 void Universe::print_on(outputStream* st, bool extended) {
1309 st->print_cr("Heap");
1310 if (!extended) {
1311 heap()->print_on(st);
1312 } else {
1313 heap()->print_extended_on(st);
1314 }
1315 }
1316
1317 void Universe::print_heap_at_SIGBREAK() {
1318 if (PrintHeapAtSIGBREAK) {
1319 MutexLocker hl(Heap_lock);
1320 print_on(tty);
1321 tty->cr();
1322 tty->flush();
1323 }
1324 }
1325
1326 void Universe::print_heap_before_gc(outputStream* st, bool ignore_extended) {
1327 st->print_cr("{Heap before GC invocations=%u (full %u):",
1328 heap()->total_collections(),
1329 heap()->total_full_collections());
1330 if (!PrintHeapAtGCExtended || ignore_extended) {
1331 heap()->print_on(st);
1332 } else {
1333 heap()->print_extended_on(st);
1334 }
1335 }
1336
1337 void Universe::print_heap_after_gc(outputStream* st, bool ignore_extended) {
1338 st->print_cr("Heap after GC invocations=%u (full %u):",
1339 heap()->total_collections(),
1340 heap()->total_full_collections());
1341 if (!PrintHeapAtGCExtended || ignore_extended) {
1342 heap()->print_on(st);
1343 } else {
1344 heap()->print_extended_on(st);
1345 }
1346 st->print_cr("}");
1347 }
1348
1349 void Universe::verify(bool silent, VerifyOption option) {
1350 if (SharedSkipVerify) {
1351 return;
1352 }
1353
1354 // The use of _verify_in_progress is a temporary work around for
1355 // 6320749. Don't bother with a creating a class to set and clear
1356 // it since it is only used in this method and the control flow is
1357 // straight forward.
1358 _verify_in_progress = true;
1359
1360 COMPILER2_PRESENT(
1361 assert(!DerivedPointerTable::is_active(),
1362 "DPT should not be active during verification "
1363 "(of thread stacks below)");
1364 )
1365
1366 ResourceMark rm;
1367 HandleMark hm; // Handles created during verification can be zapped
1368 _verify_count++;
1369
1370 if (!silent) gclog_or_tty->print("[Verifying ");
1371 if (!silent) gclog_or_tty->print("threads ");
1372 Threads::verify();
1373 heap()->verify(silent, option);
1374
1375 if (!silent) gclog_or_tty->print("syms ");
1376 SymbolTable::verify();
1377 if (!silent) gclog_or_tty->print("strs ");
1378 StringTable::verify();
1379 {
1380 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1381 if (!silent) gclog_or_tty->print("zone ");
1382 CodeCache::verify();
1383 }
1384 if (!silent) gclog_or_tty->print("dict ");
1385 SystemDictionary::verify();
1386 if (!silent) gclog_or_tty->print("hand ");
1387 JNIHandles::verify();
1388 if (!silent) gclog_or_tty->print("C-heap ");
1389 os::check_heap();
1390 if (!silent) gclog_or_tty->print("code cache ");
1391 CodeCache::verify_oops();
1392 if (!silent) gclog_or_tty->print_cr("]");
1393
1394 _verify_in_progress = false;
1395 }
1396
1397 // Oop verification (see MacroAssembler::verify_oop)
1398
1399 static uintptr_t _verify_oop_data[2] = {0, (uintptr_t)-1};
1400 static uintptr_t _verify_klass_data[2] = {0, (uintptr_t)-1};
1401
1402
1403 static void calculate_verify_data(uintptr_t verify_data[2],
1404 HeapWord* low_boundary,
1405 HeapWord* high_boundary) {
1406 assert(low_boundary < high_boundary, "bad interval");
1407
1408 // decide which low-order bits we require to be clear:
1409 size_t alignSize = MinObjAlignmentInBytes;
1410 size_t min_object_size = CollectedHeap::min_fill_size();
1411
1412 // make an inclusive limit:
1413 uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize;
1414 uintptr_t min = (uintptr_t)low_boundary;
1415 assert(min < max, "bad interval");
1416 uintptr_t diff = max ^ min;
1417
1418 // throw away enough low-order bits to make the diff vanish
1419 uintptr_t mask = (uintptr_t)(-1);
1420 while ((mask & diff) != 0)
1421 mask <<= 1;
1422 uintptr_t bits = (min & mask);
1423 assert(bits == (max & mask), "correct mask");
1424 // check an intermediate value between min and max, just to make sure:
1425 assert(bits == ((min + (max-min)/2) & mask), "correct mask");
1426
1427 // require address alignment, too:
1428 mask |= (alignSize - 1);
1429
1430 if (!(verify_data[0] == 0 && verify_data[1] == (uintptr_t)-1)) {
1431 assert(verify_data[0] == mask && verify_data[1] == bits, "mask stability");
1432 }
1433 verify_data[0] = mask;
1434 verify_data[1] = bits;
1435 }
1436
1437
1438 // Oop verification (see MacroAssembler::verify_oop)
1439 #ifndef PRODUCT
1440
1441 uintptr_t Universe::verify_oop_mask() {
1442 MemRegion m = heap()->reserved_region();
1443 calculate_verify_data(_verify_oop_data,
1444 m.start(),
1445 m.end());
1446 return _verify_oop_data[0];
1447 }
1448
1449
1450
1451 uintptr_t Universe::verify_oop_bits() {
1452 verify_oop_mask();
1453 return _verify_oop_data[1];
1454 }
1455
1456
1457 uintptr_t Universe::verify_klass_mask() {
1458 /* $$$
1459 // A klass can never live in the new space. Since the new and old
1460 // spaces can change size, we must settle for bounds-checking against
1461 // the bottom of the world, plus the smallest possible new and old
1462 // space sizes that may arise during execution.
1463 size_t min_new_size = Universe::new_size(); // in bytes
1464 size_t min_old_size = Universe::old_size(); // in bytes
1465 calculate_verify_data(_verify_klass_data,
1466 (HeapWord*)((uintptr_t)_new_gen->low_boundary + min_new_size + min_old_size),
1467 _perm_gen->high_boundary);
1468 */
1469 // Why doesn't the above just say that klass's always live in the perm
1470 // gen? I'll see if that seems to work...
1471 MemRegion permanent_reserved;
1472 switch (Universe::heap()->kind()) {
1473 default:
1474 // ???: What if a CollectedHeap doesn't have a permanent generation?
1475 ShouldNotReachHere();
1476 break;
1477 case CollectedHeap::GenCollectedHeap:
1478 case CollectedHeap::G1CollectedHeap: {
1479 SharedHeap* sh = (SharedHeap*) Universe::heap();
1480 permanent_reserved = sh->perm_gen()->reserved();
1481 break;
1482 }
1483 #ifndef SERIALGC
1484 case CollectedHeap::ParallelScavengeHeap: {
1485 ParallelScavengeHeap* psh = (ParallelScavengeHeap*) Universe::heap();
1486 permanent_reserved = psh->perm_gen()->reserved();
1487 break;
1488 }
1489 #endif // SERIALGC
1490 }
1491 calculate_verify_data(_verify_klass_data,
1492 permanent_reserved.start(),
1493 permanent_reserved.end());
1494
1495 return _verify_klass_data[0];
1496 }
1497
1498
1499
1500 uintptr_t Universe::verify_klass_bits() {
1501 verify_klass_mask();
1502 return _verify_klass_data[1];
1503 }
1504
1505
1506 uintptr_t Universe::verify_mark_mask() {
1507 return markOopDesc::lock_mask_in_place;
1508 }
1509
1510
1511
1512 uintptr_t Universe::verify_mark_bits() {
1513 intptr_t mask = verify_mark_mask();
1514 intptr_t bits = (intptr_t)markOopDesc::prototype();
1515 assert((bits & ~mask) == 0, "no stray header bits");
1516 return bits;
1517 }
1518 #endif // PRODUCT
1519
1520
1521 void Universe::compute_verify_oop_data() {
1522 verify_oop_mask();
1523 verify_oop_bits();
1524 verify_mark_mask();
1525 verify_mark_bits();
1526 verify_klass_mask();
1527 verify_klass_bits();
1528 }
1529
1530
1531 void CommonMethodOopCache::init(klassOop k, methodOop m, TRAPS) {
1532 if (!UseSharedSpaces) {
1533 _klass = k;
1534 }
1535 #ifndef PRODUCT
1536 else {
1537 // sharing initilization should have already set up _klass
1538 assert(_klass != NULL, "just checking");
1539 }
1540 #endif
1541
1542 _method_idnum = m->method_idnum();
1543 assert(_method_idnum >= 0, "sanity check");
1544 }
1545
1546
1547 ActiveMethodOopsCache::~ActiveMethodOopsCache() {
1548 if (_prev_methods != NULL) {
1549 for (int i = _prev_methods->length() - 1; i >= 0; i--) {
1550 jweak method_ref = _prev_methods->at(i);
1551 if (method_ref != NULL) {
1552 JNIHandles::destroy_weak_global(method_ref);
1553 }
1554 }
1555 delete _prev_methods;
1556 _prev_methods = NULL;
1557 }
1558 }
1559
1560
1561 void ActiveMethodOopsCache::add_previous_version(const methodOop method) {
1562 assert(Thread::current()->is_VM_thread(),
1563 "only VMThread can add previous versions");
1564
1565 if (_prev_methods == NULL) {
1566 // This is the first previous version so make some space.
1567 // Start with 2 elements under the assumption that the class
1568 // won't be redefined much.
1569 _prev_methods = new (ResourceObj::C_HEAP, mtClass) GrowableArray<jweak>(2, true);
1570 }
1571
1572 // RC_TRACE macro has an embedded ResourceMark
1573 RC_TRACE(0x00000100,
1574 ("add: %s(%s): adding prev version ref for cached method @%d",
1575 method->name()->as_C_string(), method->signature()->as_C_string(),
1576 _prev_methods->length()));
1577
1578 methodHandle method_h(method);
1579 jweak method_ref = JNIHandles::make_weak_global(method_h);
1580 _prev_methods->append(method_ref);
1581
1582 // Using weak references allows previous versions of the cached
1583 // method to be GC'ed when they are no longer needed. Since the
1584 // caller is the VMThread and we are at a safepoint, this is a good
1585 // time to clear out unused weak references.
1586
1587 for (int i = _prev_methods->length() - 1; i >= 0; i--) {
1588 jweak method_ref = _prev_methods->at(i);
1589 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
1590 if (method_ref == NULL) {
1591 _prev_methods->remove_at(i);
1592 // Since we are traversing the array backwards, we don't have to
1593 // do anything special with the index.
1594 continue; // robustness
1595 }
1596
1597 methodOop m = (methodOop)JNIHandles::resolve(method_ref);
1598 if (m == NULL) {
1599 // this method entry has been GC'ed so remove it
1600 JNIHandles::destroy_weak_global(method_ref);
1601 _prev_methods->remove_at(i);
1602 } else {
1603 // RC_TRACE macro has an embedded ResourceMark
1604 RC_TRACE(0x00000400, ("add: %s(%s): previous cached method @%d is alive",
1605 m->name()->as_C_string(), m->signature()->as_C_string(), i));
1606 }
1607 }
1608 } // end add_previous_version()
1609
1610
1611 bool ActiveMethodOopsCache::is_same_method(const methodOop method) const {
1612 instanceKlass* ik = instanceKlass::cast(klass());
1613 methodOop check_method = ik->method_with_idnum(method_idnum());
1614 assert(check_method != NULL, "sanity check");
1615 if (check_method == method) {
1616 // done with the easy case
1617 return true;
1618 }
1619
1620 if (_prev_methods != NULL) {
1621 // The cached method has been redefined at least once so search
1622 // the previous versions for a match.
1623 for (int i = 0; i < _prev_methods->length(); i++) {
1624 jweak method_ref = _prev_methods->at(i);
1625 assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
1626 if (method_ref == NULL) {
1627 continue; // robustness
1628 }
1629
1630 check_method = (methodOop)JNIHandles::resolve(method_ref);
1631 if (check_method == method) {
1632 // a previous version matches
1633 return true;
1634 }
1635 }
1636 }
1637
1638 // either no previous versions or no previous version matched
1639 return false;
1640 }
1641
1642
1643 methodOop LatestMethodOopCache::get_methodOop() {
1644 instanceKlass* ik = instanceKlass::cast(klass());
1645 methodOop m = ik->method_with_idnum(method_idnum());
1646 assert(m != NULL, "sanity check");
1647 return m;
1648 }
1649
1650
1651 #ifdef ASSERT
1652 // Release dummy object(s) at bottom of heap
1653 bool Universe::release_fullgc_alot_dummy() {
1654 MutexLocker ml(FullGCALot_lock);
1655 if (_fullgc_alot_dummy_array != NULL) {
1656 if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) {
1657 // No more dummies to release, release entire array instead
1658 _fullgc_alot_dummy_array = NULL;
1659 return false;
1660 }
1661 if (!UseConcMarkSweepGC) {
1662 // Release dummy at bottom of old generation
1663 _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
1664 }
1665 // Release dummy at bottom of permanent generation
1666 _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
1667 }
1668 return true;
1669 }
1670
1671 #endif // ASSERT