1 #ifdef USE_PRAGMA_IDENT_SRC
2 #pragma ident "@(#)ciInstanceKlass.cpp 1.45 07/09/28 10:23:23 JVM"
3 #endif
4 /*
5 * Copyright 1999-2008 Sun Microsystems, Inc. All Rights Reserved.
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7 *
8 * This code is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 only, as
10 * published by the Free Software Foundation.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
24 * have any questions.
25 *
26 */
27
28 #include "incls/_precompiled.incl"
29 #include "incls/_ciInstanceKlass.cpp.incl"
30
31 // ciInstanceKlass
32 //
33 // This class represents a klassOop in the HotSpot virtual machine
34 // whose Klass part in an instanceKlass.
35
36 // ------------------------------------------------------------------
37 // ciInstanceKlass::ciInstanceKlass
38 //
39 // Loaded instance klass.
40 ciInstanceKlass::ciInstanceKlass(KlassHandle h_k) :
41 ciKlass(h_k), _non_static_fields(NULL)
42 {
43 assert(get_Klass()->oop_is_instance(), "wrong type");
44 instanceKlass* ik = get_instanceKlass();
45
46 AccessFlags access_flags = ik->access_flags();
47 _flags = ciFlags(access_flags);
48 _has_finalizer = access_flags.has_finalizer();
49 _has_subklass = ik->subklass() != NULL;
50 _is_initialized = ik->is_initialized();
51 // Next line must follow and use the result of the previous line:
52 _is_linked = _is_initialized || ik->is_linked();
53 _nonstatic_field_size = ik->nonstatic_field_size();
54 _has_nonstatic_fields = ik->has_nonstatic_fields();
55 _nonstatic_fields = NULL; // initialized lazily by compute_nonstatic_fields:
56
57 _nof_implementors = ik->nof_implementors();
58 for (int i = 0; i < implementors_limit; i++) {
59 _implementors[i] = NULL; // we will fill these lazily
60 }
61
62 Thread *thread = Thread::current();
63 if (ciObjectFactory::is_initialized()) {
64 _loader = JNIHandles::make_local(thread, ik->class_loader());
65 _protection_domain = JNIHandles::make_local(thread,
66 ik->protection_domain());
67 _is_shared = false;
68 } else {
69 Handle h_loader(thread, ik->class_loader());
70 Handle h_protection_domain(thread, ik->protection_domain());
71 _loader = JNIHandles::make_global(h_loader);
72 _protection_domain = JNIHandles::make_global(h_protection_domain);
73 _is_shared = true;
74 }
75
76 // Lazy fields get filled in only upon request.
77 _super = NULL;
78 _java_mirror = NULL;
79
80 if (is_shared()) {
81 if (h_k() != SystemDictionary::object_klass()) {
82 super();
83 }
84 java_mirror();
85 //compute_nonstatic_fields(); // done outside of constructor
86 }
87
88 _field_cache = NULL;
89 }
90
91 // Version for unloaded classes:
92 ciInstanceKlass::ciInstanceKlass(ciSymbol* name,
93 jobject loader, jobject protection_domain)
94 : ciKlass(name, ciInstanceKlassKlass::make())
95 {
96 assert(name->byte_at(0) != '[', "not an instance klass");
97 _is_initialized = false;
98 _is_linked = false;
99 _nonstatic_field_size = -1;
100 _has_nonstatic_fields = false;
101 _nonstatic_fields = NULL;
102 _nof_implementors = -1;
103 _loader = loader;
104 _protection_domain = protection_domain;
105 _is_shared = false;
106 _super = NULL;
107 _java_mirror = NULL;
108 _field_cache = NULL;
109 }
110
111
112
113 // ------------------------------------------------------------------
114 // ciInstanceKlass::compute_shared_is_initialized
115 bool ciInstanceKlass::compute_shared_is_initialized() {
116 GUARDED_VM_ENTRY(
117 instanceKlass* ik = get_instanceKlass();
118 _is_initialized = ik->is_initialized();
119 return _is_initialized;
120 )
121 }
122
123 // ------------------------------------------------------------------
124 // ciInstanceKlass::compute_shared_is_linked
125 bool ciInstanceKlass::compute_shared_is_linked() {
126 GUARDED_VM_ENTRY(
127 instanceKlass* ik = get_instanceKlass();
128 _is_linked = ik->is_linked();
129 return _is_linked;
130 )
131 }
132
133 // ------------------------------------------------------------------
134 // ciInstanceKlass::compute_shared_has_subklass
135 bool ciInstanceKlass::compute_shared_has_subklass() {
136 GUARDED_VM_ENTRY(
137 instanceKlass* ik = get_instanceKlass();
138 _has_subklass = ik->subklass() != NULL;
139 return _has_subklass;
140 )
141 }
142
143 // ------------------------------------------------------------------
144 // ciInstanceKlass::compute_shared_nof_implementors
145 int ciInstanceKlass::compute_shared_nof_implementors() {
146 // We requery this property, since it is a very old ciObject.
147 GUARDED_VM_ENTRY(
148 instanceKlass* ik = get_instanceKlass();
149 _nof_implementors = ik->nof_implementors();
150 return _nof_implementors;
151 )
152 }
153
154 // ------------------------------------------------------------------
155 // ciInstanceKlass::loader
156 oop ciInstanceKlass::loader() {
157 ASSERT_IN_VM;
158 return JNIHandles::resolve(_loader);
159 }
160
161 // ------------------------------------------------------------------
162 // ciInstanceKlass::loader_handle
163 jobject ciInstanceKlass::loader_handle() {
164 return _loader;
165 }
166
167 // ------------------------------------------------------------------
168 // ciInstanceKlass::protection_domain
169 oop ciInstanceKlass::protection_domain() {
170 ASSERT_IN_VM;
171 return JNIHandles::resolve(_protection_domain);
172 }
173
174 // ------------------------------------------------------------------
175 // ciInstanceKlass::protection_domain_handle
176 jobject ciInstanceKlass::protection_domain_handle() {
177 return _protection_domain;
178 }
179
180 // ------------------------------------------------------------------
181 // ciInstanceKlass::field_cache
182 //
183 // Get the field cache associated with this klass.
184 ciConstantPoolCache* ciInstanceKlass::field_cache() {
185 if (is_shared()) {
186 return NULL;
187 }
188 if (_field_cache == NULL) {
189 assert(!is_java_lang_Object(), "Object has no fields");
190 Arena* arena = CURRENT_ENV->arena();
191 _field_cache = new (arena) ciConstantPoolCache(arena, 5);
192 }
193 return _field_cache;
194 }
195
196 // ------------------------------------------------------------------
197 // ciInstanceKlass::get_canonical_holder
198 //
199 ciInstanceKlass* ciInstanceKlass::get_canonical_holder(int offset) {
200 #ifdef ASSERT
201 if (!(offset >= 0 && offset < layout_helper())) {
202 tty->print("*** get_canonical_holder(%d) on ", offset);
203 this->print();
204 tty->print_cr(" ***");
205 };
206 assert(offset >= 0 && offset < layout_helper(), "offset must be tame");
207 #endif
208
209 if (offset < instanceOopDesc::base_offset_in_bytes()) {
210 // All header offsets belong properly to java/lang/Object.
211 return CURRENT_ENV->Object_klass();
212 }
213
214 ciInstanceKlass* self = this;
215 for (;;) {
216 assert(self->is_loaded(), "must be loaded to have size");
217 ciInstanceKlass* super = self->super();
218 if (super == NULL || super->nof_nonstatic_fields() == 0 ||
219 !super->contains_field_offset(offset)) {
220 return self;
221 } else {
222 self = super; // return super->get_canonical_holder(offset)
223 }
224 }
225 }
226
227 // ------------------------------------------------------------------
228 // ciInstanceKlass::is_java_lang_Object
229 //
230 // Is this klass java.lang.Object?
231 bool ciInstanceKlass::is_java_lang_Object() {
232 return equals(CURRENT_ENV->Object_klass());
233 }
234
235 // ------------------------------------------------------------------
236 // ciInstanceKlass::uses_default_loader
237 bool ciInstanceKlass::uses_default_loader() {
238 VM_ENTRY_MARK;
239 return loader() == NULL;
240 }
241
242 // ------------------------------------------------------------------
243 // ciInstanceKlass::print_impl
244 //
245 // Implementation of the print method.
246 void ciInstanceKlass::print_impl(outputStream* st) {
247 ciKlass::print_impl(st);
248 GUARDED_VM_ENTRY(st->print(" loader=0x%x", (address)loader());)
249 if (is_loaded()) {
250 st->print(" loaded=true initialized=%s finalized=%s subklass=%s size=%d flags=",
251 bool_to_str(is_initialized()),
252 bool_to_str(has_finalizer()),
253 bool_to_str(has_subklass()),
254 layout_helper());
255
256 _flags.print_klass_flags();
257
258 if (_super) {
259 st->print(" super=");
260 _super->print_name();
261 }
262 if (_java_mirror) {
263 st->print(" mirror=PRESENT");
264 }
265 } else {
266 st->print(" loaded=false");
267 }
268 }
269
270 // ------------------------------------------------------------------
271 // ciInstanceKlass::super
272 //
273 // Get the superklass of this klass.
274 ciInstanceKlass* ciInstanceKlass::super() {
275 assert(is_loaded(), "must be loaded");
276 if (_super == NULL && !is_java_lang_Object()) {
277 GUARDED_VM_ENTRY(
278 klassOop super_klass = get_instanceKlass()->super();
279 _super = CURRENT_ENV->get_object(super_klass)->as_instance_klass();
280 )
281 }
282 return _super;
283 }
284
285 // ------------------------------------------------------------------
286 // ciInstanceKlass::java_mirror
287 //
288 // Get the instance of java.lang.Class corresponding to this klass.
289 ciInstance* ciInstanceKlass::java_mirror() {
290 assert(is_loaded(), "must be loaded");
291 if (_java_mirror == NULL) {
292 _java_mirror = ciKlass::java_mirror();
293 }
294 return _java_mirror;
295 }
296
297 // ------------------------------------------------------------------
298 // ciInstanceKlass::unique_concrete_subklass
299 ciInstanceKlass* ciInstanceKlass::unique_concrete_subklass() {
300 if (!is_loaded()) return NULL; // No change if class is not loaded
301 if (!is_abstract()) return NULL; // Only applies to abstract classes.
302 if (!has_subklass()) return NULL; // Must have at least one subklass.
303 VM_ENTRY_MARK;
304 instanceKlass* ik = get_instanceKlass();
305 Klass* up = ik->up_cast_abstract();
306 assert(up->oop_is_instance(), "must be instanceKlass");
307 if (ik == up) {
308 return NULL;
309 }
310 return CURRENT_THREAD_ENV->get_object(up->as_klassOop())->as_instance_klass();
311 }
312
313 // ------------------------------------------------------------------
314 // ciInstanceKlass::has_finalizable_subclass
315 bool ciInstanceKlass::has_finalizable_subclass() {
316 if (!is_loaded()) return true;
317 VM_ENTRY_MARK;
318 return Dependencies::find_finalizable_subclass(get_instanceKlass()) != NULL;
319 }
320
321 // ------------------------------------------------------------------
322 // ciInstanceKlass::get_field_by_offset
323 ciField* ciInstanceKlass::get_field_by_offset(int field_offset, bool is_static) {
324 if (!is_static) {
325 for (int i = 0, len = nof_nonstatic_fields(); i < len; i++) {
326 ciField* field = _nonstatic_fields->at(i);
327 int field_off = field->offset_in_bytes();
328 if (field_off == field_offset)
329 return field;
330 if (field_off > field_offset)
331 break;
332 // could do binary search or check bins, but probably not worth it
333 }
334 return NULL;
335 }
336 VM_ENTRY_MARK;
337 instanceKlass* k = get_instanceKlass();
338 fieldDescriptor fd;
339 if (!k->find_field_from_offset(field_offset, is_static, &fd)) {
340 return NULL;
341 }
342 ciField* field = new (CURRENT_THREAD_ENV->arena()) ciField(&fd);
343 return field;
344 }
345
346 // ------------------------------------------------------------------
347 // ciInstanceKlass::non_static_fields.
348
349 class NonStaticFieldFiller: public FieldClosure {
350 GrowableArray<ciField*>* _arr;
351 ciEnv* _curEnv;
352 public:
353 NonStaticFieldFiller(ciEnv* curEnv, GrowableArray<ciField*>* arr) :
354 _curEnv(curEnv), _arr(arr)
355 {}
356 void do_field(fieldDescriptor* fd) {
357 ciField* field = new (_curEnv->arena()) ciField(fd);
358 _arr->append(field);
359 }
360 };
361
362 GrowableArray<ciField*>* ciInstanceKlass::non_static_fields() {
363 if (_non_static_fields == NULL) {
364 VM_ENTRY_MARK;
365 ciEnv* curEnv = ciEnv::current();
366 instanceKlass* ik = get_instanceKlass();
367 int max_n_fields = ik->fields()->length()/instanceKlass::next_offset;
368
369 _non_static_fields =
370 new (curEnv->arena()) GrowableArray<ciField*>(max_n_fields);
371 NonStaticFieldFiller filler(curEnv, _non_static_fields);
372 ik->do_nonstatic_fields(&filler);
373 }
374 return _non_static_fields;
375 }
376
377 static int sort_field_by_offset(ciField** a, ciField** b) {
378 return (*a)->offset_in_bytes() - (*b)->offset_in_bytes();
379 // (no worries about 32-bit overflow...)
380 }
381
382 // ------------------------------------------------------------------
383 // ciInstanceKlass::compute_nonstatic_fields
384 int ciInstanceKlass::compute_nonstatic_fields() {
385 assert(is_loaded(), "must be loaded");
386
387 if (_nonstatic_fields != NULL)
388 return _nonstatic_fields->length();
389
390 if (!has_nonstatic_fields()) {
391 Arena* arena = CURRENT_ENV->arena();
392 _nonstatic_fields = new (arena) GrowableArray<ciField*>(arena, 0, 0, NULL);
393 return 0;
394 }
395 assert(!is_java_lang_Object(), "bootstrap OK");
396
397 // Size in bytes of my fields, including inherited fields.
398 int fsize = nonstatic_field_size() * heapOopSize;
399
400 ciInstanceKlass* super = this->super();
401 GrowableArray<ciField*>* super_fields = NULL;
402 if (super != NULL && super->has_nonstatic_fields()) {
403 int super_fsize = super->nonstatic_field_size() * heapOopSize;
404 int super_flen = super->nof_nonstatic_fields();
405 super_fields = super->_nonstatic_fields;
406 assert(super_flen == 0 || super_fields != NULL, "first get nof_fields");
407 // See if I am no larger than my super; if so, I can use his fields.
408 if (fsize == super_fsize) {
409 _nonstatic_fields = super_fields;
410 return super_fields->length();
411 }
412 }
413
414 GrowableArray<ciField*>* fields = NULL;
415 GUARDED_VM_ENTRY({
416 fields = compute_nonstatic_fields_impl(super_fields);
417 });
418
419 if (fields == NULL) {
420 // This can happen if this class (java.lang.Class) has invisible fields.
421 _nonstatic_fields = super_fields;
422 return super_fields->length();
423 }
424
425 int flen = fields->length();
426
427 // Now sort them by offset, ascending.
428 // (In principle, they could mix with superclass fields.)
429 fields->sort(sort_field_by_offset);
430 #ifdef ASSERT
431 int last_offset = instanceOopDesc::base_offset_in_bytes();
432 for (int i = 0; i < fields->length(); i++) {
433 ciField* field = fields->at(i);
434 int offset = field->offset_in_bytes();
435 int size = (field->_type == NULL) ? heapOopSize : field->size_in_bytes();
436 assert(last_offset <= offset, "no field overlap");
437 if (last_offset > (int)sizeof(oopDesc))
438 assert((offset - last_offset) < BytesPerLong, "no big holes");
439 // Note: Two consecutive T_BYTE fields will be separated by wordSize-1
440 // padding bytes if one of them is declared by a superclass.
441 // This is a minor inefficiency classFileParser.cpp.
442 last_offset = offset + size;
443 }
444 assert(last_offset <= (int)instanceOopDesc::base_offset_in_bytes() + fsize, "no overflow");
445 #endif
446
447 _nonstatic_fields = fields;
448 return flen;
449 }
450
451 GrowableArray<ciField*>*
452 ciInstanceKlass::compute_nonstatic_fields_impl(GrowableArray<ciField*>*
453 super_fields) {
454 ASSERT_IN_VM;
455 Arena* arena = CURRENT_ENV->arena();
456 int flen = 0;
457 GrowableArray<ciField*>* fields = NULL;
458 instanceKlass* k = get_instanceKlass();
459 typeArrayOop fields_array = k->fields();
460 for (int pass = 0; pass <= 1; pass++) {
461 for (int i = 0, alen = fields_array->length(); i < alen; i += instanceKlass::next_offset) {
462 fieldDescriptor fd;
463 fd.initialize(k->as_klassOop(), i);
464 if (fd.is_static()) continue;
465 if (pass == 0) {
466 flen += 1;
467 } else {
468 ciField* field = new (arena) ciField(&fd);
469 fields->append(field);
470 }
471 }
472
473 // Between passes, allocate the array:
474 if (pass == 0) {
475 if (flen == 0) {
476 return NULL; // return nothing if none are locally declared
477 }
478 if (super_fields != NULL) {
479 flen += super_fields->length();
480 }
481 fields = new (arena) GrowableArray<ciField*>(arena, flen, 0, NULL);
482 if (super_fields != NULL) {
483 fields->appendAll(super_fields);
484 }
485 }
486 }
487 assert(fields->length() == flen, "sanity");
488 return fields;
489 }
490
491 // ------------------------------------------------------------------
492 // ciInstanceKlass::find_method
493 //
494 // Find a method in this klass.
495 ciMethod* ciInstanceKlass::find_method(ciSymbol* name, ciSymbol* signature) {
496 VM_ENTRY_MARK;
497 instanceKlass* k = get_instanceKlass();
498 symbolOop name_sym = name->get_symbolOop();
499 symbolOop sig_sym= signature->get_symbolOop();
500
501 methodOop m = k->find_method(name_sym, sig_sym);
502 if (m == NULL) return NULL;
503
504 return CURRENT_THREAD_ENV->get_object(m)->as_method();
505 }
506
507 // ------------------------------------------------------------------
508 // ciInstanceKlass::is_leaf_type
509 bool ciInstanceKlass::is_leaf_type() {
510 assert(is_loaded(), "must be loaded");
511 if (is_shared()) {
512 return is_final(); // approximately correct
513 } else {
514 return !_has_subklass && (_nof_implementors == 0);
515 }
516 }
517
518 // ------------------------------------------------------------------
519 // ciInstanceKlass::implementor
520 //
521 // Report an implementor of this interface.
522 // Returns NULL if exact information is not available.
523 // Note that there are various races here, since my copy
524 // of _nof_implementors might be out of date with respect
525 // to results returned by instanceKlass::implementor.
526 // This is OK, since any dependencies we decide to assert
527 // will be checked later under the Compile_lock.
528 ciInstanceKlass* ciInstanceKlass::implementor(int n) {
529 if (n > implementors_limit) {
530 return NULL;
531 }
532 ciInstanceKlass* impl = _implementors[n];
533 if (impl == NULL) {
534 if (_nof_implementors > implementors_limit) {
535 return NULL;
536 }
537 // Go into the VM to fetch the implementor.
538 {
539 VM_ENTRY_MARK;
540 klassOop k = get_instanceKlass()->implementor(n);
541 if (k != NULL) {
542 impl = CURRENT_THREAD_ENV->get_object(k)->as_instance_klass();
543 }
544 }
545 // Memoize this result.
546 if (!is_shared()) {
547 _implementors[n] = (impl == NULL)? this: impl;
548 }
549 } else if (impl == this) {
550 impl = NULL; // memoized null result from a VM query
551 }
552 return impl;
553 }