1 /*
2 * Copyright (c) 1998, 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 */
24
25 #include "precompiled.hpp"
26 #include "gc_implementation/shared/markSweep.inline.hpp"
27 #include "interpreter/interpreter.hpp"
28 #include "interpreter/rewriter.hpp"
29 #include "memory/universe.inline.hpp"
30 #include "oops/cpCache.hpp"
31 #include "oops/objArrayOop.hpp"
32 #include "oops/oop.inline.hpp"
33 #include "prims/jvmtiRedefineClassesTrace.hpp"
34 #include "prims/methodHandles.hpp"
35 #include "runtime/handles.inline.hpp"
36 #include "utilities/macros.hpp"
37 #if INCLUDE_ALL_GCS
38 # include "gc_implementation/parallelScavenge/psPromotionManager.hpp"
39 #endif // INCLUDE_ALL_GCS
40
41
42 // Implememtation of ConstantPoolCacheEntry
43
44 void ConstantPoolCacheEntry::initialize_entry(int index) {
45 assert(0 < index && index < 0x10000, "sanity check");
46 _indices = index;
47 _f1 = NULL;
48 _f2 = _flags = 0;
49 assert(constant_pool_index() == index, "");
50 }
51
52 int ConstantPoolCacheEntry::make_flags(TosState state,
53 int option_bits,
54 int field_index_or_method_params) {
55 assert(state < number_of_states, "Invalid state in make_flags");
56 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
57 // Preserve existing flag bit values
58 // The low bits are a field offset, or else the method parameter size.
59 #ifdef ASSERT
60 TosState old_state = flag_state();
61 assert(old_state == (TosState)0 || old_state == state,
62 "inconsistent cpCache flags state");
63 #endif
64 return (_flags | f) ;
65 }
66
67 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
68 #ifdef ASSERT
69 // Read once.
70 volatile Bytecodes::Code c = bytecode_1();
71 assert(c == 0 || c == code || code == 0, "update must be consistent");
72 #endif
73 // Need to flush pending stores here before bytecode is written.
74 OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << bytecode_1_shift));
75 }
76
77 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
78 #ifdef ASSERT
79 // Read once.
80 volatile Bytecodes::Code c = bytecode_2();
81 assert(c == 0 || c == code || code == 0, "update must be consistent");
82 #endif
83 // Need to flush pending stores here before bytecode is written.
84 OrderAccess::release_store_ptr(&_indices, _indices | ((u_char)code << bytecode_2_shift));
85 }
86
87 // Sets f1, ordering with previous writes.
88 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
89 assert(f1 != NULL, "");
90 OrderAccess::release_store_ptr((HeapWord*) &_f1, f1);
91 }
92
93 // Sets flags, but only if the value was previously zero.
94 bool ConstantPoolCacheEntry::init_flags_atomic(intptr_t flags) {
95 intptr_t result = Atomic::cmpxchg_ptr(flags, &_flags, 0);
96 return (result == 0);
97 }
98
99 // Note that concurrent update of both bytecodes can leave one of them
100 // reset to zero. This is harmless; the interpreter will simply re-resolve
101 // the damaged entry. More seriously, the memory synchronization is needed
102 // to flush other fields (f1, f2) completely to memory before the bytecodes
103 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
104 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
105 Bytecodes::Code put_code,
106 KlassHandle field_holder,
107 int field_index,
108 int field_offset,
109 TosState field_type,
110 bool is_final,
111 bool is_volatile,
112 Klass* root_klass) {
113 set_f1(field_holder());
114 set_f2(field_offset);
115 assert((field_index & field_index_mask) == field_index,
116 "field index does not fit in low flag bits");
117 set_field_flags(field_type,
118 ((is_volatile ? 1 : 0) << is_volatile_shift) |
119 ((is_final ? 1 : 0) << is_final_shift),
120 field_index);
121 set_bytecode_1(get_code);
122 set_bytecode_2(put_code);
123 NOT_PRODUCT(verify(tty));
124 }
125
126 void ConstantPoolCacheEntry::set_parameter_size(int value) {
127 // This routine is called only in corner cases where the CPCE is not yet initialized.
128 // See AbstractInterpreter::deopt_continue_after_entry.
129 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
130 err_msg("size must not change: parameter_size=%d, value=%d", parameter_size(), value));
131 // Setting the parameter size by itself is only safe if the
132 // current value of _flags is 0, otherwise another thread may have
133 // updated it and we don't want to overwrite that value. Don't
134 // bother trying to update it once it's nonzero but always make
135 // sure that the final parameter size agrees with what was passed.
136 if (_flags == 0) {
137 Atomic::cmpxchg_ptr((value & parameter_size_mask), &_flags, 0);
138 }
139 guarantee(parameter_size() == value,
140 err_msg("size must not change: parameter_size=%d, value=%d", parameter_size(), value));
141 }
142
143 void ConstantPoolCacheEntry::set_method(Bytecodes::Code invoke_code,
144 methodHandle method,
145 int vtable_index) {
146 assert(method->interpreter_entry() != NULL, "should have been set at this point");
147 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
148
149 int byte_no = -1;
150 bool change_to_virtual = false;
151
152 switch (invoke_code) {
153 case Bytecodes::_invokeinterface:
154 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
155 // instruction somehow links to a non-interface method (in Object).
156 // In that case, the method has no itable index and must be invoked as a virtual.
157 // Set a flag to keep track of this corner case.
158 change_to_virtual = true;
159
160 // ...and fall through as if we were handling invokevirtual:
161 case Bytecodes::_invokevirtual:
162 {
163 if (method->can_be_statically_bound()) {
164 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
165 set_method_flags(as_TosState(method->result_type()),
166 ( 1 << is_vfinal_shift) |
167 ((method->is_final_method() ? 1 : 0) << is_final_shift) |
168 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
169 method()->size_of_parameters());
170 set_f2_as_vfinal_method(method());
171 } else {
172 assert(vtable_index >= 0, "valid index");
173 assert(!method->is_final_method(), "sanity");
174 set_method_flags(as_TosState(method->result_type()),
175 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
176 method()->size_of_parameters());
177 set_f2(vtable_index);
178 }
179 byte_no = 2;
180 break;
181 }
182
183 case Bytecodes::_invokespecial:
184 case Bytecodes::_invokestatic:
185 // Note: Read and preserve the value of the is_vfinal flag on any
186 // invokevirtual bytecode shared with this constant pool cache entry.
187 // It is cheap and safe to consult is_vfinal() at all times.
188 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
189 set_method_flags(as_TosState(method->result_type()),
190 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
191 ((method->is_final_method() ? 1 : 0) << is_final_shift),
192 method()->size_of_parameters());
193 set_f1(method());
194 byte_no = 1;
195 break;
196 default:
197 ShouldNotReachHere();
198 break;
199 }
200
201 // Note: byte_no also appears in TemplateTable::resolve.
202 if (byte_no == 1) {
203 assert(invoke_code != Bytecodes::_invokevirtual &&
204 invoke_code != Bytecodes::_invokeinterface, "");
205 set_bytecode_1(invoke_code);
206 } else if (byte_no == 2) {
207 if (change_to_virtual) {
208 assert(invoke_code == Bytecodes::_invokeinterface, "");
209 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
210 //
211 // Workaround for the case where we encounter an invokeinterface, but we
212 // should really have an _invokevirtual since the resolved method is a
213 // virtual method in java.lang.Object. This is a corner case in the spec
214 // but is presumably legal. javac does not generate this code.
215 //
216 // We set bytecode_1() to _invokeinterface, because that is the
217 // bytecode # used by the interpreter to see if it is resolved.
218 // We set bytecode_2() to _invokevirtual.
219 // See also interpreterRuntime.cpp. (8/25/2000)
220 // Only set resolved for the invokeinterface case if method is public.
221 // Otherwise, the method needs to be reresolved with caller for each
222 // interface call.
223 if (method->is_public()) set_bytecode_1(invoke_code);
224 } else {
225 assert(invoke_code == Bytecodes::_invokevirtual, "");
226 }
227 // set up for invokevirtual, even if linking for invokeinterface also:
228 set_bytecode_2(Bytecodes::_invokevirtual);
229 } else {
230 ShouldNotReachHere();
231 }
232 NOT_PRODUCT(verify(tty));
233 }
234
235
236 void ConstantPoolCacheEntry::set_interface_call(methodHandle method, int index) {
237 InstanceKlass* interf = method->method_holder();
238 assert(interf->is_interface(), "must be an interface");
239 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
240 set_f1(interf);
241 set_f2(index);
242 set_method_flags(as_TosState(method->result_type()),
243 0, // no option bits
244 method()->size_of_parameters());
245 set_bytecode_1(Bytecodes::_invokeinterface);
246 }
247
248
249 void ConstantPoolCacheEntry::set_method_handle(constantPoolHandle cpool, const CallInfo &call_info) {
250 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
251 }
252
253 void ConstantPoolCacheEntry::set_dynamic_call(constantPoolHandle cpool, const CallInfo &call_info) {
254 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
255 }
256
257 void ConstantPoolCacheEntry::set_method_handle_common(constantPoolHandle cpool,
258 Bytecodes::Code invoke_code,
259 const CallInfo &call_info) {
260 // NOTE: This CPCE can be the subject of data races.
261 // There are three words to update: flags, refs[f2], f1 (in that order).
262 // Writers must store all other values before f1.
263 // Readers must test f1 first for non-null before reading other fields.
264 // Competing writers must acquire exclusive access via a lock.
265 // A losing writer waits on the lock until the winner writes f1 and leaves
266 // the lock, so that when the losing writer returns, he can use the linked
267 // cache entry.
268
269 oop cplock = cpool->lock();
270 ObjectLocker ol(cplock, Thread::current(), cplock != NULL);
271 if (!is_f1_null()) {
272 return;
273 }
274
275 const methodHandle adapter = call_info.resolved_method();
276 const Handle appendix = call_info.resolved_appendix();
277 const Handle method_type = call_info.resolved_method_type();
278 const bool has_appendix = appendix.not_null();
279 const bool has_method_type = method_type.not_null();
280
281 // Write the flags.
282 set_method_flags(as_TosState(adapter->result_type()),
283 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
284 ((has_method_type ? 1 : 0) << has_method_type_shift) |
285 ( 1 << is_final_shift ),
286 adapter->size_of_parameters());
287
288 if (TraceInvokeDynamic) {
289 tty->print_cr("set_method_handle bc=%d appendix="PTR_FORMAT"%s method_type="PTR_FORMAT"%s method="PTR_FORMAT" ",
290 invoke_code,
291 (intptr_t)appendix(), (has_appendix ? "" : " (unused)"),
292 (intptr_t)method_type(), (has_method_type ? "" : " (unused)"),
293 (intptr_t)adapter());
294 adapter->print();
295 if (has_appendix) appendix()->print();
296 }
297
298 // Method handle invokes and invokedynamic sites use both cp cache words.
299 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
300 // In the general case, this could be the call site's MethodType,
301 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
302 // f1 contains the adapter method which manages the actual call.
303 // In the general case, this is a compiled LambdaForm.
304 // (The Java code is free to optimize these calls by binding other
305 // sorts of methods and appendices to call sites.)
306 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
307 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
308 // Even with the appendix, the method will never take more than 255 parameter slots.
309 //
310 // This means that given a call site like (List)mh.invoke("foo"),
311 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
312 // not '(Ljava/lang/String;)Ljava/util/List;'.
313 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
314 // This allows us to create fewer method oops, while keeping type safety.
315 //
316
317 objArrayHandle resolved_references = cpool->resolved_references();
318 // Store appendix, if any.
319 if (has_appendix) {
320 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
321 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
322 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
323 resolved_references->obj_at_put(appendix_index, appendix());
324 }
325
326 // Store MethodType, if any.
327 if (has_method_type) {
328 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
329 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
330 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
331 resolved_references->obj_at_put(method_type_index, method_type());
332 }
333
334 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
335
336 // The interpreter assembly code does not check byte_2,
337 // but it is used by is_resolved, method_if_resolved, etc.
338 set_bytecode_1(invoke_code);
339 NOT_PRODUCT(verify(tty));
340 if (TraceInvokeDynamic) {
341 this->print(tty, 0);
342 }
343 }
344
345 Method* ConstantPoolCacheEntry::method_if_resolved(constantPoolHandle cpool) {
346 // Decode the action of set_method and set_interface_call
347 Bytecodes::Code invoke_code = bytecode_1();
348 if (invoke_code != (Bytecodes::Code)0) {
349 Metadata* f1 = (Metadata*)_f1;
350 if (f1 != NULL) {
351 switch (invoke_code) {
352 case Bytecodes::_invokeinterface:
353 assert(f1->is_klass(), "");
354 return klassItable::method_for_itable_index((Klass*)f1, f2_as_index());
355 case Bytecodes::_invokestatic:
356 case Bytecodes::_invokespecial:
357 assert(!has_appendix(), "");
358 case Bytecodes::_invokehandle:
359 case Bytecodes::_invokedynamic:
360 assert(f1->is_method(), "");
361 return (Method*)f1;
362 }
363 }
364 }
365 invoke_code = bytecode_2();
366 if (invoke_code != (Bytecodes::Code)0) {
367 switch (invoke_code) {
368 case Bytecodes::_invokevirtual:
369 if (is_vfinal()) {
370 // invokevirtual
371 Method* m = f2_as_vfinal_method();
372 assert(m->is_method(), "");
373 return m;
374 } else {
375 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
376 if (cpool->tag_at(holder_index).is_klass()) {
377 Klass* klass = cpool->resolved_klass_at(holder_index);
378 if (!klass->oop_is_instance())
379 klass = SystemDictionary::Object_klass();
380 return InstanceKlass::cast(klass)->method_at_vtable(f2_as_index());
381 }
382 }
383 break;
384 }
385 }
386 return NULL;
387 }
388
389
390 oop ConstantPoolCacheEntry::appendix_if_resolved(constantPoolHandle cpool) {
391 if (is_f1_null() || !has_appendix())
392 return NULL;
393 const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset;
394 objArrayOop resolved_references = cpool->resolved_references();
395 return resolved_references->obj_at(ref_index);
396 }
397
398
399 oop ConstantPoolCacheEntry::method_type_if_resolved(constantPoolHandle cpool) {
400 if (is_f1_null() || !has_method_type())
401 return NULL;
402 const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset;
403 objArrayOop resolved_references = cpool->resolved_references();
404 return resolved_references->obj_at(ref_index);
405 }
406
407
408 #if INCLUDE_JVMTI
409 // RedefineClasses() API support:
410 // If this ConstantPoolCacheEntry refers to old_method then update it
411 // to refer to new_method.
412 bool ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
413 Method* new_method, bool * trace_name_printed) {
414
415 if (is_vfinal()) {
416 // virtual and final so _f2 contains method ptr instead of vtable index
417 if (f2_as_vfinal_method() == old_method) {
418 // match old_method so need an update
419 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
420 _f2 = (intptr_t)new_method;
421 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
422 if (!(*trace_name_printed)) {
423 // RC_TRACE_MESG macro has an embedded ResourceMark
424 RC_TRACE_MESG(("adjust: name=%s",
425 old_method->method_holder()->external_name()));
426 *trace_name_printed = true;
427 }
428 // RC_TRACE macro has an embedded ResourceMark
429 RC_TRACE(0x00400000, ("cpc vf-entry update: %s(%s)",
430 new_method->name()->as_C_string(),
431 new_method->signature()->as_C_string()));
432 }
433
434 return true;
435 }
436
437 // f1() is not used with virtual entries so bail out
438 return false;
439 }
440
441 if (_f1 == NULL) {
442 // NULL f1() means this is a virtual entry so bail out
443 // We are assuming that the vtable index does not need change.
444 return false;
445 }
446
447 if (_f1 == old_method) {
448 _f1 = new_method;
449 if (RC_TRACE_IN_RANGE(0x00100000, 0x00400000)) {
450 if (!(*trace_name_printed)) {
451 // RC_TRACE_MESG macro has an embedded ResourceMark
452 RC_TRACE_MESG(("adjust: name=%s",
453 old_method->method_holder()->external_name()));
454 *trace_name_printed = true;
455 }
456 // RC_TRACE macro has an embedded ResourceMark
457 RC_TRACE(0x00400000, ("cpc entry update: %s(%s)",
458 new_method->name()->as_C_string(),
459 new_method->signature()->as_C_string()));
460 }
461
462 return true;
463 }
464
465 return false;
466 }
467
468 // a constant pool cache entry should never contain old or obsolete methods
469 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
470 if (is_vfinal()) {
471 // virtual and final so _f2 contains method ptr instead of vtable index
472 Metadata* f2 = (Metadata*)_f2;
473 // Return false if _f2 refers to an old or an obsolete method.
474 // _f2 == NULL || !_f2->is_method() are just as unexpected here.
475 return (f2 != NULL NOT_PRODUCT(&& f2->is_valid()) && f2->is_method() &&
476 !((Method*)f2)->is_old() && !((Method*)f2)->is_obsolete());
477 } else if (_f1 == NULL ||
478 (NOT_PRODUCT(_f1->is_valid() &&) !_f1->is_method())) {
479 // _f1 == NULL || !_f1->is_method() are OK here
480 return true;
481 }
482 // return false if _f1 refers to an old or an obsolete method
483 return (NOT_PRODUCT(_f1->is_valid() &&) _f1->is_method() &&
484 !((Method*)_f1)->is_old() && !((Method*)_f1)->is_obsolete());
485 }
486
487 bool ConstantPoolCacheEntry::is_interesting_method_entry(Klass* k) {
488 if (!is_method_entry()) {
489 // not a method entry so not interesting by default
490 return false;
491 }
492
493 Method* m = NULL;
494 if (is_vfinal()) {
495 // virtual and final so _f2 contains method ptr instead of vtable index
496 m = f2_as_vfinal_method();
497 } else if (is_f1_null()) {
498 // NULL _f1 means this is a virtual entry so also not interesting
499 return false;
500 } else {
501 if (!(_f1->is_method())) {
502 // _f1 can also contain a Klass* for an interface
503 return false;
504 }
505 m = f1_as_method();
506 }
507
508 assert(m != NULL && m->is_method(), "sanity check");
509 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
510 // robustness for above sanity checks or method is not in
511 // the interesting class
512 return false;
513 }
514
515 // the method is in the interesting class so the entry is interesting
516 return true;
517 }
518 #endif // INCLUDE_JVMTI
519
520 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
521 // print separator
522 if (index == 0) st->print_cr(" -------------");
523 // print entry
524 st->print("%3d ("PTR_FORMAT") ", index, (intptr_t)this);
525 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
526 constant_pool_index());
527 st->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_f1);
528 st->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_f2);
529 st->print_cr(" [ "PTR_FORMAT"]", (intptr_t)_flags);
530 st->print_cr(" -------------");
531 }
532
533 void ConstantPoolCacheEntry::verify(outputStream* st) const {
534 // not implemented yet
535 }
536
537 // Implementation of ConstantPoolCache
538
539 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
540 int length,
541 const intStack& index_map,
542 const intStack& invokedynamic_map, TRAPS) {
543 int size = ConstantPoolCache::size(length);
544
545 return new (loader_data, size, false, MetaspaceObj::ConstantPoolCacheType, THREAD)
546 ConstantPoolCache(length, index_map, invokedynamic_map);
547 }
548
549 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
550 const intArray& invokedynamic_references_map) {
551 assert(inverse_index_map.length() == length(), "inverse index map must have same length as cache");
552 for (int i = 0; i < length(); i++) {
553 ConstantPoolCacheEntry* e = entry_at(i);
554 int original_index = inverse_index_map[i];
555 e->initialize_entry(original_index);
556 assert(entry_at(i) == e, "sanity");
557 }
558 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
559 const int cpci = invokedynamic_references_map[ref];
560 if (cpci >= 0) {
561 #ifdef ASSERT
562 // invokedynamic and invokehandle have more entries; check if they
563 // all point to the same constant pool cache entry.
564 for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
565 const int cpci_next = invokedynamic_references_map[ref + entry];
566 assert(cpci == cpci_next, err_msg_res("%d == %d", cpci, cpci_next));
567 }
568 #endif
569 entry_at(cpci)->initialize_resolved_reference_index(ref);
570 ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries
571 }
572 }
573 }
574
575 #if INCLUDE_JVMTI
576 // RedefineClasses() API support:
577 // If any entry of this ConstantPoolCache points to any of
578 // old_methods, replace it with the corresponding new_method.
579 void ConstantPoolCache::adjust_method_entries(Method** old_methods, Method** new_methods,
580 int methods_length, bool * trace_name_printed) {
581
582 if (methods_length == 0) {
583 // nothing to do if there are no methods
584 return;
585 }
586
587 // get shorthand for the interesting class
588 Klass* old_holder = old_methods[0]->method_holder();
589
590 for (int i = 0; i < length(); i++) {
591 if (!entry_at(i)->is_interesting_method_entry(old_holder)) {
592 // skip uninteresting methods
593 continue;
594 }
595
596 // The ConstantPoolCache contains entries for several different
597 // things, but we only care about methods. In fact, we only care
598 // about methods in the same class as the one that contains the
599 // old_methods. At this point, we have an interesting entry.
600
601 for (int j = 0; j < methods_length; j++) {
602 Method* old_method = old_methods[j];
603 Method* new_method = new_methods[j];
604
605 if (entry_at(i)->adjust_method_entry(old_method, new_method,
606 trace_name_printed)) {
607 // current old_method matched this entry and we updated it so
608 // break out and get to the next interesting entry if there one
609 break;
610 }
611 }
612 }
613 }
614
615 // the constant pool cache should never contain old or obsolete methods
616 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
617 for (int i = 1; i < length(); i++) {
618 if (entry_at(i)->is_interesting_method_entry(NULL) &&
619 !entry_at(i)->check_no_old_or_obsolete_entries()) {
620 return false;
621 }
622 }
623 return true;
624 }
625
626 void ConstantPoolCache::dump_cache() {
627 for (int i = 1; i < length(); i++) {
628 if (entry_at(i)->is_interesting_method_entry(NULL)) {
629 entry_at(i)->print(tty, i);
630 }
631 }
632 }
633 #endif // INCLUDE_JVMTI
634
635
636 // Printing
637
638 void ConstantPoolCache::print_on(outputStream* st) const {
639 assert(is_constantPoolCache(), "obj must be constant pool cache");
640 st->print_cr(internal_name());
641 // print constant pool cache entries
642 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
643 }
644
645 void ConstantPoolCache::print_value_on(outputStream* st) const {
646 assert(is_constantPoolCache(), "obj must be constant pool cache");
647 st->print("cache [%d]", length());
648 print_address_on(st);
649 st->print(" for ");
650 constant_pool()->print_value_on(st);
651 }
652
653
654 // Verification
655
656 void ConstantPoolCache::verify_on(outputStream* st) {
657 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
658 // print constant pool cache entries
659 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
660 }