Mon, 07 Jul 2014 10:12:40 +0200
8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com
1 /*
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #include "precompiled.hpp"
26 #include "ci/ciCallSite.hpp"
27 #include "ci/ciInstance.hpp"
28 #include "ci/ciInstanceKlass.hpp"
29 #include "ci/ciMemberName.hpp"
30 #include "ci/ciMethod.hpp"
31 #include "ci/ciMethodData.hpp"
32 #include "ci/ciMethodHandle.hpp"
33 #include "ci/ciMethodType.hpp"
34 #include "ci/ciNullObject.hpp"
35 #include "ci/ciObjArray.hpp"
36 #include "ci/ciObjArrayKlass.hpp"
37 #include "ci/ciObject.hpp"
38 #include "ci/ciObjectFactory.hpp"
39 #include "ci/ciSymbol.hpp"
40 #include "ci/ciTypeArray.hpp"
41 #include "ci/ciTypeArrayKlass.hpp"
42 #include "ci/ciUtilities.hpp"
43 #include "classfile/systemDictionary.hpp"
44 #include "gc_interface/collectedHeap.inline.hpp"
45 #include "memory/allocation.inline.hpp"
46 #include "oops/oop.inline.hpp"
47 #include "oops/oop.inline2.hpp"
48 #include "runtime/fieldType.hpp"
49 #if INCLUDE_ALL_GCS
50 # include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
51 #endif
53 // ciObjectFactory
54 //
55 // This class handles requests for the creation of new instances
56 // of ciObject and its subclasses. It contains a caching mechanism
57 // which ensures that for each oop, at most one ciObject is created.
58 // This invariant allows more efficient implementation of ciObject.
59 //
60 // Implementation note: the oop->ciObject mapping is represented as
61 // a table stored in an array. Even though objects are moved
62 // by the garbage collector, the compactor preserves their relative
63 // order; address comparison of oops (in perm space) is safe so long
64 // as we prohibit GC during our comparisons. We currently use binary
65 // search to find the oop in the table, and inserting a new oop
66 // into the table may be costly. If this cost ends up being
67 // problematic the underlying data structure can be switched to some
68 // sort of balanced binary tree.
70 GrowableArray<ciMetadata*>* ciObjectFactory::_shared_ci_metadata = NULL;
71 ciSymbol* ciObjectFactory::_shared_ci_symbols[vmSymbols::SID_LIMIT];
72 int ciObjectFactory::_shared_ident_limit = 0;
73 volatile bool ciObjectFactory::_initialized = false;
76 // ------------------------------------------------------------------
77 // ciObjectFactory::ciObjectFactory
78 ciObjectFactory::ciObjectFactory(Arena* arena,
79 int expected_size) {
81 for (int i = 0; i < NON_PERM_BUCKETS; i++) {
82 _non_perm_bucket[i] = NULL;
83 }
84 _non_perm_count = 0;
86 _next_ident = _shared_ident_limit;
87 _arena = arena;
88 _ci_metadata = new (arena) GrowableArray<ciMetadata*>(arena, expected_size, 0, NULL);
90 // If the shared ci objects exist append them to this factory's objects
92 if (_shared_ci_metadata != NULL) {
93 _ci_metadata->appendAll(_shared_ci_metadata);
94 }
96 _unloaded_methods = new (arena) GrowableArray<ciMethod*>(arena, 4, 0, NULL);
97 _unloaded_klasses = new (arena) GrowableArray<ciKlass*>(arena, 8, 0, NULL);
98 _unloaded_instances = new (arena) GrowableArray<ciInstance*>(arena, 4, 0, NULL);
99 _return_addresses =
100 new (arena) GrowableArray<ciReturnAddress*>(arena, 8, 0, NULL);
102 _symbols = new (arena) GrowableArray<ciSymbol*>(arena, 100, 0, NULL);
103 }
105 // ------------------------------------------------------------------
106 // ciObjectFactory::ciObjectFactory
107 void ciObjectFactory::initialize() {
108 ASSERT_IN_VM;
109 JavaThread* thread = JavaThread::current();
110 HandleMark handle_mark(thread);
112 // This Arena is long lived and exists in the resource mark of the
113 // compiler thread that initializes the initial ciObjectFactory which
114 // creates the shared ciObjects that all later ciObjectFactories use.
115 Arena* arena = new (mtCompiler) Arena();
116 ciEnv initial(arena);
117 ciEnv* env = ciEnv::current();
118 env->_factory->init_shared_objects();
120 _initialized = true;
122 }
124 void ciObjectFactory::init_shared_objects() {
126 _next_ident = 1; // start numbering CI objects at 1
128 {
129 // Create the shared symbols, but not in _shared_ci_metadata.
130 int i;
131 for (i = vmSymbols::FIRST_SID; i < vmSymbols::SID_LIMIT; i++) {
132 Symbol* vmsym = vmSymbols::symbol_at((vmSymbols::SID) i);
133 assert(vmSymbols::find_sid(vmsym) == i, "1-1 mapping");
134 ciSymbol* sym = new (_arena) ciSymbol(vmsym, (vmSymbols::SID) i);
135 init_ident_of(sym);
136 _shared_ci_symbols[i] = sym;
137 }
138 #ifdef ASSERT
139 for (i = vmSymbols::FIRST_SID; i < vmSymbols::SID_LIMIT; i++) {
140 Symbol* vmsym = vmSymbols::symbol_at((vmSymbols::SID) i);
141 ciSymbol* sym = vm_symbol_at((vmSymbols::SID) i);
142 assert(sym->get_symbol() == vmsym, "oop must match");
143 }
144 assert(ciSymbol::void_class_signature()->get_symbol() == vmSymbols::void_class_signature(), "spot check");
145 #endif
146 }
148 _ci_metadata = new (_arena) GrowableArray<ciMetadata*>(_arena, 64, 0, NULL);
150 for (int i = T_BOOLEAN; i <= T_CONFLICT; i++) {
151 BasicType t = (BasicType)i;
152 if (type2name(t) != NULL && t != T_OBJECT && t != T_ARRAY && t != T_NARROWOOP && t != T_NARROWKLASS) {
153 ciType::_basic_types[t] = new (_arena) ciType(t);
154 init_ident_of(ciType::_basic_types[t]);
155 }
156 }
158 ciEnv::_null_object_instance = new (_arena) ciNullObject();
159 init_ident_of(ciEnv::_null_object_instance);
161 #define WK_KLASS_DEFN(name, ignore_s, opt) \
162 if (SystemDictionary::name() != NULL) \
163 ciEnv::_##name = get_metadata(SystemDictionary::name())->as_instance_klass();
165 WK_KLASSES_DO(WK_KLASS_DEFN)
166 #undef WK_KLASS_DEFN
168 for (int len = -1; len != _ci_metadata->length(); ) {
169 len = _ci_metadata->length();
170 for (int i2 = 0; i2 < len; i2++) {
171 ciMetadata* obj = _ci_metadata->at(i2);
172 assert (obj->is_metadata(), "what else would it be?");
173 if (obj->is_loaded() && obj->is_instance_klass()) {
174 obj->as_instance_klass()->compute_nonstatic_fields();
175 }
176 }
177 }
179 ciEnv::_unloaded_cisymbol = ciObjectFactory::get_symbol(vmSymbols::dummy_symbol());
180 // Create dummy InstanceKlass and ObjArrayKlass object and assign them idents
181 ciEnv::_unloaded_ciinstance_klass = new (_arena) ciInstanceKlass(ciEnv::_unloaded_cisymbol, NULL, NULL);
182 init_ident_of(ciEnv::_unloaded_ciinstance_klass);
183 ciEnv::_unloaded_ciobjarrayklass = new (_arena) ciObjArrayKlass(ciEnv::_unloaded_cisymbol, ciEnv::_unloaded_ciinstance_klass, 1);
184 init_ident_of(ciEnv::_unloaded_ciobjarrayklass);
185 assert(ciEnv::_unloaded_ciobjarrayklass->is_obj_array_klass(), "just checking");
187 get_metadata(Universe::boolArrayKlassObj());
188 get_metadata(Universe::charArrayKlassObj());
189 get_metadata(Universe::singleArrayKlassObj());
190 get_metadata(Universe::doubleArrayKlassObj());
191 get_metadata(Universe::byteArrayKlassObj());
192 get_metadata(Universe::shortArrayKlassObj());
193 get_metadata(Universe::intArrayKlassObj());
194 get_metadata(Universe::longArrayKlassObj());
198 assert(_non_perm_count == 0, "no shared non-perm objects");
200 // The shared_ident_limit is the first ident number that will
201 // be used for non-shared objects. That is, numbers less than
202 // this limit are permanently assigned to shared CI objects,
203 // while the higher numbers are recycled afresh by each new ciEnv.
205 _shared_ident_limit = _next_ident;
206 _shared_ci_metadata = _ci_metadata;
207 }
210 ciSymbol* ciObjectFactory::get_symbol(Symbol* key) {
211 vmSymbols::SID sid = vmSymbols::find_sid(key);
212 if (sid != vmSymbols::NO_SID) {
213 // do not pollute the main cache with it
214 return vm_symbol_at(sid);
215 }
217 assert(vmSymbols::find_sid(key) == vmSymbols::NO_SID, "");
218 ciSymbol* s = new (arena()) ciSymbol(key, vmSymbols::NO_SID);
219 _symbols->push(s);
220 return s;
221 }
223 // Decrement the refcount when done on symbols referenced by this compilation.
224 void ciObjectFactory::remove_symbols() {
225 for (int i = 0; i < _symbols->length(); i++) {
226 ciSymbol* s = _symbols->at(i);
227 s->get_symbol()->decrement_refcount();
228 }
229 // Since _symbols is resource allocated we're not allowed to delete it
230 // but it'll go away just the same.
231 }
233 // ------------------------------------------------------------------
234 // ciObjectFactory::get
235 //
236 // Get the ciObject corresponding to some oop. If the ciObject has
237 // already been created, it is returned. Otherwise, a new ciObject
238 // is created.
239 ciObject* ciObjectFactory::get(oop key) {
240 ASSERT_IN_VM;
242 assert(key == NULL || Universe::heap()->is_in_reserved(key), "must be");
244 NonPermObject* &bucket = find_non_perm(key);
245 if (bucket != NULL) {
246 return bucket->object();
247 }
249 // The ciObject does not yet exist. Create it and insert it
250 // into the cache.
251 Handle keyHandle(key);
252 ciObject* new_object = create_new_object(keyHandle());
253 assert(keyHandle() == new_object->get_oop(), "must be properly recorded");
254 init_ident_of(new_object);
255 assert(Universe::heap()->is_in_reserved(new_object->get_oop()), "must be");
257 // Not a perm-space object.
258 insert_non_perm(bucket, keyHandle(), new_object);
259 return new_object;
260 }
262 // ------------------------------------------------------------------
263 // ciObjectFactory::get
264 //
265 // Get the ciObject corresponding to some oop. If the ciObject has
266 // already been created, it is returned. Otherwise, a new ciObject
267 // is created.
268 ciMetadata* ciObjectFactory::get_metadata(Metadata* key) {
269 ASSERT_IN_VM;
271 #ifdef ASSERT
272 if (CIObjectFactoryVerify) {
273 Metadata* last = NULL;
274 for (int j = 0; j< _ci_metadata->length(); j++) {
275 Metadata* o = _ci_metadata->at(j)->constant_encoding();
276 assert(last < o, "out of order");
277 last = o;
278 }
279 }
280 #endif // ASSERT
281 int len = _ci_metadata->length();
282 int index = find(key, _ci_metadata);
283 #ifdef ASSERT
284 if (CIObjectFactoryVerify) {
285 for (int i=0; i<_ci_metadata->length(); i++) {
286 if (_ci_metadata->at(i)->constant_encoding() == key) {
287 assert(index == i, " bad lookup");
288 }
289 }
290 }
291 #endif
292 if (!is_found_at(index, key, _ci_metadata)) {
293 // The ciObject does not yet exist. Create it and insert it
294 // into the cache.
295 ciMetadata* new_object = create_new_object(key);
296 init_ident_of(new_object);
297 assert(new_object->is_metadata(), "must be");
299 if (len != _ci_metadata->length()) {
300 // creating the new object has recursively entered new objects
301 // into the table. We need to recompute our index.
302 index = find(key, _ci_metadata);
303 }
304 assert(!is_found_at(index, key, _ci_metadata), "no double insert");
305 insert(index, new_object, _ci_metadata);
306 return new_object;
307 }
308 return _ci_metadata->at(index)->as_metadata();
309 }
311 // ------------------------------------------------------------------
312 // ciObjectFactory::create_new_object
313 //
314 // Create a new ciObject from an oop.
315 //
316 // Implementation note: this functionality could be virtual behavior
317 // of the oop itself. For now, we explicitly marshal the object.
318 ciObject* ciObjectFactory::create_new_object(oop o) {
319 EXCEPTION_CONTEXT;
321 if (o->is_instance()) {
322 instanceHandle h_i(THREAD, (instanceOop)o);
323 if (java_lang_invoke_CallSite::is_instance(o))
324 return new (arena()) ciCallSite(h_i);
325 else if (java_lang_invoke_MemberName::is_instance(o))
326 return new (arena()) ciMemberName(h_i);
327 else if (java_lang_invoke_MethodHandle::is_instance(o))
328 return new (arena()) ciMethodHandle(h_i);
329 else if (java_lang_invoke_MethodType::is_instance(o))
330 return new (arena()) ciMethodType(h_i);
331 else
332 return new (arena()) ciInstance(h_i);
333 } else if (o->is_objArray()) {
334 objArrayHandle h_oa(THREAD, (objArrayOop)o);
335 return new (arena()) ciObjArray(h_oa);
336 } else if (o->is_typeArray()) {
337 typeArrayHandle h_ta(THREAD, (typeArrayOop)o);
338 return new (arena()) ciTypeArray(h_ta);
339 }
341 // The oop is of some type not supported by the compiler interface.
342 ShouldNotReachHere();
343 return NULL;
344 }
346 // ------------------------------------------------------------------
347 // ciObjectFactory::create_new_object
348 //
349 // Create a new ciObject from a Metadata*.
350 //
351 // Implementation note: this functionality could be virtual behavior
352 // of the oop itself. For now, we explicitly marshal the object.
353 ciMetadata* ciObjectFactory::create_new_object(Metadata* o) {
354 EXCEPTION_CONTEXT;
356 if (o->is_klass()) {
357 KlassHandle h_k(THREAD, (Klass*)o);
358 Klass* k = (Klass*)o;
359 if (k->oop_is_instance()) {
360 return new (arena()) ciInstanceKlass(h_k);
361 } else if (k->oop_is_objArray()) {
362 return new (arena()) ciObjArrayKlass(h_k);
363 } else if (k->oop_is_typeArray()) {
364 return new (arena()) ciTypeArrayKlass(h_k);
365 }
366 } else if (o->is_method()) {
367 methodHandle h_m(THREAD, (Method*)o);
368 return new (arena()) ciMethod(h_m);
369 } else if (o->is_methodData()) {
370 // Hold methodHandle alive - might not be necessary ???
371 methodHandle h_m(THREAD, ((MethodData*)o)->method());
372 return new (arena()) ciMethodData((MethodData*)o);
373 }
375 // The oop is of some type not supported by the compiler interface.
376 ShouldNotReachHere();
377 return NULL;
378 }
380 // ------------------------------------------------------------------
381 // ciObjectFactory::ensure_metadata_alive
382 //
383 // Ensure that the metadata wrapped by the ciMetadata is kept alive by GC.
384 // This is primarily useful for metadata which is considered as weak roots
385 // by the GC but need to be strong roots if reachable from a current compilation.
386 //
387 void ciObjectFactory::ensure_metadata_alive(ciMetadata* m) {
388 ASSERT_IN_VM; // We're handling raw oops here.
390 #if INCLUDE_ALL_GCS
391 if (!UseG1GC) {
392 return;
393 }
394 Klass* metadata_owner_klass;
395 if (m->is_klass()) {
396 metadata_owner_klass = m->as_klass()->get_Klass();
397 } else if (m->is_method()) {
398 metadata_owner_klass = m->as_method()->get_Method()->constants()->pool_holder();
399 } else {
400 fatal("Not implemented for other types of metadata");
401 }
403 oop metadata_holder = metadata_owner_klass->klass_holder();
404 if (metadata_holder != NULL) {
405 G1SATBCardTableModRefBS::enqueue(metadata_holder);
406 }
408 #endif
409 }
411 //------------------------------------------------------------------
412 // ciObjectFactory::get_unloaded_method
413 //
414 // Get the ciMethod representing an unloaded/unfound method.
415 //
416 // Implementation note: unloaded methods are currently stored in
417 // an unordered array, requiring a linear-time lookup for each
418 // unloaded method. This may need to change.
419 ciMethod* ciObjectFactory::get_unloaded_method(ciInstanceKlass* holder,
420 ciSymbol* name,
421 ciSymbol* signature,
422 ciInstanceKlass* accessor) {
423 ciSignature* that = NULL;
424 for (int i = 0; i < _unloaded_methods->length(); i++) {
425 ciMethod* entry = _unloaded_methods->at(i);
426 if (entry->holder()->equals(holder) &&
427 entry->name()->equals(name) &&
428 entry->signature()->as_symbol()->equals(signature)) {
429 // Short-circuit slow resolve.
430 if (entry->signature()->accessing_klass() == accessor) {
431 // We've found a match.
432 return entry;
433 } else {
434 // Lazily create ciSignature
435 if (that == NULL) that = new (arena()) ciSignature(accessor, constantPoolHandle(), signature);
436 if (entry->signature()->equals(that)) {
437 // We've found a match.
438 return entry;
439 }
440 }
441 }
442 }
444 // This is a new unloaded method. Create it and stick it in
445 // the cache.
446 ciMethod* new_method = new (arena()) ciMethod(holder, name, signature, accessor);
448 init_ident_of(new_method);
449 _unloaded_methods->append(new_method);
451 return new_method;
452 }
454 //------------------------------------------------------------------
455 // ciObjectFactory::get_unloaded_klass
456 //
457 // Get a ciKlass representing an unloaded klass.
458 //
459 // Implementation note: unloaded klasses are currently stored in
460 // an unordered array, requiring a linear-time lookup for each
461 // unloaded klass. This may need to change.
462 ciKlass* ciObjectFactory::get_unloaded_klass(ciKlass* accessing_klass,
463 ciSymbol* name,
464 bool create_if_not_found) {
465 EXCEPTION_CONTEXT;
466 oop loader = NULL;
467 oop domain = NULL;
468 if (accessing_klass != NULL) {
469 loader = accessing_klass->loader();
470 domain = accessing_klass->protection_domain();
471 }
472 for (int i=0; i<_unloaded_klasses->length(); i++) {
473 ciKlass* entry = _unloaded_klasses->at(i);
474 if (entry->name()->equals(name) &&
475 entry->loader() == loader &&
476 entry->protection_domain() == domain) {
477 // We've found a match.
478 return entry;
479 }
480 }
482 if (!create_if_not_found)
483 return NULL;
485 // This is a new unloaded klass. Create it and stick it in
486 // the cache.
487 ciKlass* new_klass = NULL;
489 // Two cases: this is an unloaded ObjArrayKlass or an
490 // unloaded InstanceKlass. Deal with both.
491 if (name->byte_at(0) == '[') {
492 // Decompose the name.'
493 FieldArrayInfo fd;
494 BasicType element_type = FieldType::get_array_info(name->get_symbol(),
495 fd, THREAD);
496 if (HAS_PENDING_EXCEPTION) {
497 CLEAR_PENDING_EXCEPTION;
498 CURRENT_THREAD_ENV->record_out_of_memory_failure();
499 return ciEnv::_unloaded_ciobjarrayklass;
500 }
501 int dimension = fd.dimension();
502 assert(element_type != T_ARRAY, "unsuccessful decomposition");
503 ciKlass* element_klass = NULL;
504 if (element_type == T_OBJECT) {
505 ciEnv *env = CURRENT_THREAD_ENV;
506 ciSymbol* ci_name = env->get_symbol(fd.object_key());
507 element_klass =
508 env->get_klass_by_name(accessing_klass, ci_name, false)->as_instance_klass();
509 } else {
510 assert(dimension > 1, "one dimensional type arrays are always loaded.");
512 // The type array itself takes care of one of the dimensions.
513 dimension--;
515 // The element klass is a TypeArrayKlass.
516 element_klass = ciTypeArrayKlass::make(element_type);
517 }
518 new_klass = new (arena()) ciObjArrayKlass(name, element_klass, dimension);
519 } else {
520 jobject loader_handle = NULL;
521 jobject domain_handle = NULL;
522 if (accessing_klass != NULL) {
523 loader_handle = accessing_klass->loader_handle();
524 domain_handle = accessing_klass->protection_domain_handle();
525 }
526 new_klass = new (arena()) ciInstanceKlass(name, loader_handle, domain_handle);
527 }
528 init_ident_of(new_klass);
529 _unloaded_klasses->append(new_klass);
531 return new_klass;
532 }
535 //------------------------------------------------------------------
536 // ciObjectFactory::get_unloaded_instance
537 //
538 // Get a ciInstance representing an as-yet undetermined instance of a given class.
539 //
540 ciInstance* ciObjectFactory::get_unloaded_instance(ciInstanceKlass* instance_klass) {
541 for (int i=0; i<_unloaded_instances->length(); i++) {
542 ciInstance* entry = _unloaded_instances->at(i);
543 if (entry->klass()->equals(instance_klass)) {
544 // We've found a match.
545 return entry;
546 }
547 }
549 // This is a new unloaded instance. Create it and stick it in
550 // the cache.
551 ciInstance* new_instance = new (arena()) ciInstance(instance_klass);
553 init_ident_of(new_instance);
554 _unloaded_instances->append(new_instance);
556 // make sure it looks the way we want:
557 assert(!new_instance->is_loaded(), "");
558 assert(new_instance->klass() == instance_klass, "");
560 return new_instance;
561 }
564 //------------------------------------------------------------------
565 // ciObjectFactory::get_unloaded_klass_mirror
566 //
567 // Get a ciInstance representing an unresolved klass mirror.
568 //
569 // Currently, this ignores the parameters and returns a unique unloaded instance.
570 ciInstance* ciObjectFactory::get_unloaded_klass_mirror(ciKlass* type) {
571 assert(ciEnv::_Class_klass != NULL, "");
572 return get_unloaded_instance(ciEnv::_Class_klass->as_instance_klass());
573 }
575 //------------------------------------------------------------------
576 // ciObjectFactory::get_unloaded_method_handle_constant
577 //
578 // Get a ciInstance representing an unresolved method handle constant.
579 //
580 // Currently, this ignores the parameters and returns a unique unloaded instance.
581 ciInstance* ciObjectFactory::get_unloaded_method_handle_constant(ciKlass* holder,
582 ciSymbol* name,
583 ciSymbol* signature,
584 int ref_kind) {
585 if (ciEnv::_MethodHandle_klass == NULL) return NULL;
586 return get_unloaded_instance(ciEnv::_MethodHandle_klass->as_instance_klass());
587 }
589 //------------------------------------------------------------------
590 // ciObjectFactory::get_unloaded_method_type_constant
591 //
592 // Get a ciInstance representing an unresolved method type constant.
593 //
594 // Currently, this ignores the parameters and returns a unique unloaded instance.
595 ciInstance* ciObjectFactory::get_unloaded_method_type_constant(ciSymbol* signature) {
596 if (ciEnv::_MethodType_klass == NULL) return NULL;
597 return get_unloaded_instance(ciEnv::_MethodType_klass->as_instance_klass());
598 }
600 ciInstance* ciObjectFactory::get_unloaded_object_constant() {
601 if (ciEnv::_Object_klass == NULL) return NULL;
602 return get_unloaded_instance(ciEnv::_Object_klass->as_instance_klass());
603 }
605 //------------------------------------------------------------------
606 // ciObjectFactory::get_empty_methodData
607 //
608 // Get the ciMethodData representing the methodData for a method with
609 // none.
610 ciMethodData* ciObjectFactory::get_empty_methodData() {
611 ciMethodData* new_methodData = new (arena()) ciMethodData();
612 init_ident_of(new_methodData);
613 return new_methodData;
614 }
616 //------------------------------------------------------------------
617 // ciObjectFactory::get_return_address
618 //
619 // Get a ciReturnAddress for a specified bci.
620 ciReturnAddress* ciObjectFactory::get_return_address(int bci) {
621 for (int i=0; i<_return_addresses->length(); i++) {
622 ciReturnAddress* entry = _return_addresses->at(i);
623 if (entry->bci() == bci) {
624 // We've found a match.
625 return entry;
626 }
627 }
629 ciReturnAddress* new_ret_addr = new (arena()) ciReturnAddress(bci);
630 init_ident_of(new_ret_addr);
631 _return_addresses->append(new_ret_addr);
632 return new_ret_addr;
633 }
635 // ------------------------------------------------------------------
636 // ciObjectFactory::init_ident_of
637 void ciObjectFactory::init_ident_of(ciBaseObject* obj) {
638 obj->set_ident(_next_ident++);
639 }
641 // ------------------------------------------------------------------
642 // ciObjectFactory::find
643 //
644 // Use binary search to find the position of this oop in the cache.
645 // If there is no entry in the cache corresponding to this oop, return
646 // the position at which the oop should be inserted.
647 int ciObjectFactory::find(Metadata* key, GrowableArray<ciMetadata*>* objects) {
648 int min = 0;
649 int max = objects->length()-1;
651 // print_contents();
653 while (max >= min) {
654 int mid = (max + min) / 2;
655 Metadata* value = objects->at(mid)->constant_encoding();
656 if (value < key) {
657 min = mid + 1;
658 } else if (value > key) {
659 max = mid - 1;
660 } else {
661 return mid;
662 }
663 }
664 return min;
665 }
667 // ------------------------------------------------------------------
668 // ciObjectFactory::is_found_at
669 //
670 // Verify that the binary seach found the given key.
671 bool ciObjectFactory::is_found_at(int index, Metadata* key, GrowableArray<ciMetadata*>* objects) {
672 return (index < objects->length() &&
673 objects->at(index)->constant_encoding() == key);
674 }
677 // ------------------------------------------------------------------
678 // ciObjectFactory::insert
679 //
680 // Insert a ciObject into the table at some index.
681 void ciObjectFactory::insert(int index, ciMetadata* obj, GrowableArray<ciMetadata*>* objects) {
682 int len = objects->length();
683 if (len == index) {
684 objects->append(obj);
685 } else {
686 objects->append(objects->at(len-1));
687 int pos;
688 for (pos = len-2; pos >= index; pos--) {
689 objects->at_put(pos+1,objects->at(pos));
690 }
691 objects->at_put(index, obj);
692 }
693 }
695 static ciObjectFactory::NonPermObject* emptyBucket = NULL;
697 // ------------------------------------------------------------------
698 // ciObjectFactory::find_non_perm
699 //
700 // Use a small hash table, hashed on the klass of the key.
701 // If there is no entry in the cache corresponding to this oop, return
702 // the null tail of the bucket into which the oop should be inserted.
703 ciObjectFactory::NonPermObject* &ciObjectFactory::find_non_perm(oop key) {
704 assert(Universe::heap()->is_in_reserved_or_null(key), "must be");
705 ciMetadata* klass = get_metadata(key->klass());
706 NonPermObject* *bp = &_non_perm_bucket[(unsigned) klass->hash() % NON_PERM_BUCKETS];
707 for (NonPermObject* p; (p = (*bp)) != NULL; bp = &p->next()) {
708 if (is_equal(p, key)) break;
709 }
710 return (*bp);
711 }
715 // ------------------------------------------------------------------
716 // Code for for NonPermObject
717 //
718 inline ciObjectFactory::NonPermObject::NonPermObject(ciObjectFactory::NonPermObject* &bucket, oop key, ciObject* object) {
719 assert(ciObjectFactory::is_initialized(), "");
720 _object = object;
721 _next = bucket;
722 bucket = this;
723 }
727 // ------------------------------------------------------------------
728 // ciObjectFactory::insert_non_perm
729 //
730 // Insert a ciObject into the non-perm table.
731 void ciObjectFactory::insert_non_perm(ciObjectFactory::NonPermObject* &where, oop key, ciObject* obj) {
732 assert(Universe::heap()->is_in_reserved_or_null(key), "must be");
733 assert(&where != &emptyBucket, "must not try to fill empty bucket");
734 NonPermObject* p = new (arena()) NonPermObject(where, key, obj);
735 assert(where == p && is_equal(p, key) && p->object() == obj, "entry must match");
736 assert(find_non_perm(key) == p, "must find the same spot");
737 ++_non_perm_count;
738 }
740 // ------------------------------------------------------------------
741 // ciObjectFactory::vm_symbol_at
742 // Get the ciSymbol corresponding to some index in vmSymbols.
743 ciSymbol* ciObjectFactory::vm_symbol_at(int index) {
744 assert(index >= vmSymbols::FIRST_SID && index < vmSymbols::SID_LIMIT, "oob");
745 return _shared_ci_symbols[index];
746 }
748 // ------------------------------------------------------------------
749 // ciObjectFactory::metadata_do
750 void ciObjectFactory::metadata_do(void f(Metadata*)) {
751 if (_ci_metadata == NULL) return;
752 for (int j = 0; j< _ci_metadata->length(); j++) {
753 Metadata* o = _ci_metadata->at(j)->constant_encoding();
754 f(o);
755 }
756 }
758 // ------------------------------------------------------------------
759 // ciObjectFactory::print_contents_impl
760 void ciObjectFactory::print_contents_impl() {
761 int len = _ci_metadata->length();
762 tty->print_cr("ciObjectFactory (%d) meta data contents:", len);
763 for (int i=0; i<len; i++) {
764 _ci_metadata->at(i)->print();
765 tty->cr();
766 }
767 }
769 // ------------------------------------------------------------------
770 // ciObjectFactory::print_contents
771 void ciObjectFactory::print_contents() {
772 print();
773 tty->cr();
774 GUARDED_VM_ENTRY(print_contents_impl();)
775 }
777 // ------------------------------------------------------------------
778 // ciObjectFactory::print
779 //
780 // Print debugging information about the object factory
781 void ciObjectFactory::print() {
782 tty->print("<ciObjectFactory oops=%d metadata=%d unloaded_methods=%d unloaded_instances=%d unloaded_klasses=%d>",
783 _non_perm_count, _ci_metadata->length(), _unloaded_methods->length(),
784 _unloaded_instances->length(),
785 _unloaded_klasses->length());
786 }