1 /*
2 * Copyright (c) 1998, 2019, 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/resolutionErrors.hpp"
27 #include "interpreter/bytecodeStream.hpp"
28 #include "interpreter/bytecodes.hpp"
29 #include "interpreter/interpreter.hpp"
30 #include "interpreter/linkResolver.hpp"
31 #include "interpreter/rewriter.hpp"
32 #include "logging/log.hpp"
33 #include "memory/heapShared.hpp"
34 #include "memory/metadataFactory.hpp"
35 #include "memory/metaspaceClosure.hpp"
36 #include "memory/metaspaceShared.hpp"
37 #include "memory/resourceArea.hpp"
38 #include "memory/universe.hpp"
39 #include "oops/access.inline.hpp"
40 #include "oops/constantPool.inline.hpp"
41 #include "oops/cpCache.inline.hpp"
42 #include "oops/objArrayOop.inline.hpp"
43 #include "oops/oop.inline.hpp"
44 #include "prims/methodHandles.hpp"
45 #include "runtime/atomic.hpp"
46 #include "runtime/handles.inline.hpp"
47 #include "runtime/orderAccess.hpp"
48 #include "utilities/macros.hpp"
49
50 // Implementation of ConstantPoolCacheEntry
51
52 void ConstantPoolCacheEntry::initialize_entry(int index) {
53 assert(0 < index && index < 0x10000, "sanity check");
54 _indices = index;
55 _f1 = NULL;
56 _f2 = _flags = 0;
57 assert(constant_pool_index() == index, "");
58 }
59
60 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) {
61 assert((_indices & (~cp_index_mask)) == 0, "sanity");
62 assert(_f1 == NULL, "sanity");
63 assert(_flags == 0, "sanity");
64 if (!f2_used) {
65 assert(_f2 == 0, "sanity");
66 }
67 }
68
69 void ConstantPoolCacheEntry::reinitialize(bool f2_used) {
70 _indices &= cp_index_mask;
71 _f1 = NULL;
72 _flags = 0;
73 if (!f2_used) {
74 _f2 = 0;
75 }
76 }
77
78 int ConstantPoolCacheEntry::make_flags(TosState state,
79 int option_bits,
80 int field_index_or_method_params) {
81 assert(state < number_of_states, "Invalid state in make_flags");
82 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
83 // Preserve existing flag bit values
84 // The low bits are a field offset, or else the method parameter size.
85 #ifdef ASSERT
86 TosState old_state = flag_state();
87 assert(old_state == (TosState)0 || old_state == state,
88 "inconsistent cpCache flags state");
89 #endif
90 return (_flags | f) ;
91 }
92
93 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
94 #ifdef ASSERT
95 // Read once.
96 volatile Bytecodes::Code c = bytecode_1();
97 assert(c == 0 || c == code || code == 0, "update must be consistent");
98 #endif
99 // Need to flush pending stores here before bytecode is written.
100 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift));
101 }
102
103 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
104 #ifdef ASSERT
105 // Read once.
106 volatile Bytecodes::Code c = bytecode_2();
107 assert(c == 0 || c == code || code == 0, "update must be consistent");
108 #endif
109 // Need to flush pending stores here before bytecode is written.
110 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift));
111 }
112
113 // Sets f1, ordering with previous writes.
114 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
115 assert(f1 != NULL, "");
116 OrderAccess::release_store(&_f1, f1);
117 }
118
119 void ConstantPoolCacheEntry::set_indy_resolution_failed() {
120 OrderAccess::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift));
121 }
122
123 // Note that concurrent update of both bytecodes can leave one of them
124 // reset to zero. This is harmless; the interpreter will simply re-resolve
125 // the damaged entry. More seriously, the memory synchronization is needed
126 // to flush other fields (f1, f2) completely to memory before the bytecodes
127 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
128 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
129 Bytecodes::Code put_code,
130 Klass* field_holder,
131 int field_index,
132 int field_offset,
133 TosState field_type,
134 bool is_final,
135 bool is_volatile,
136 Klass* root_klass) {
137 set_f1(field_holder);
138 set_f2(field_offset);
139 assert((field_index & field_index_mask) == field_index,
140 "field index does not fit in low flag bits");
141 set_field_flags(field_type,
142 ((is_volatile ? 1 : 0) << is_volatile_shift) |
143 ((is_final ? 1 : 0) << is_final_shift),
144 field_index);
145 set_bytecode_1(get_code);
146 set_bytecode_2(put_code);
147 NOT_PRODUCT(verify(tty));
148 }
149
150 void ConstantPoolCacheEntry::set_parameter_size(int value) {
151 // This routine is called only in corner cases where the CPCE is not yet initialized.
152 // See AbstractInterpreter::deopt_continue_after_entry.
153 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
154 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
155 // Setting the parameter size by itself is only safe if the
156 // current value of _flags is 0, otherwise another thread may have
157 // updated it and we don't want to overwrite that value. Don't
158 // bother trying to update it once it's nonzero but always make
159 // sure that the final parameter size agrees with what was passed.
160 if (_flags == 0) {
161 intx newflags = (value & parameter_size_mask);
162 Atomic::cmpxchg(newflags, &_flags, (intx)0);
163 }
164 guarantee(parameter_size() == value,
165 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
166 }
167
168 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
169 const methodHandle& method,
170 int vtable_index,
171 bool sender_is_interface,
172 InstanceKlass* pool_holder) {
173 bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean
174 assert(method->interpreter_entry() != NULL, "should have been set at this point");
175 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
176
177 int byte_no = -1;
178 bool change_to_virtual = false;
179 InstanceKlass* holder = NULL; // have to declare this outside the switch
180 switch (invoke_code) {
181 case Bytecodes::_invokeinterface:
182 holder = method->method_holder();
183 // check for private interface method invocations
184 if (vtable_index == Method::nonvirtual_vtable_index && holder->is_interface() ) {
185 assert(method->is_private(), "unexpected non-private method");
186 assert(method->can_be_statically_bound(), "unexpected non-statically-bound method");
187 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
188 set_method_flags(as_TosState(method->result_type()),
189 ( 1 << is_vfinal_shift) |
190 ((method->is_final_method() ? 1 : 0) << is_final_shift),
191 method()->size_of_parameters());
192 set_f2_as_vfinal_method(method());
193 byte_no = 2;
194 set_f1(holder); // interface klass*
195 break;
196 }
197 else {
198 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
199 // instruction links to a non-interface method (in Object). This can happen when
200 // an interface redeclares an Object method (like CharSequence declaring toString())
201 // or when invokeinterface is used explicitly.
202 // In that case, the method has no itable index and must be invoked as a virtual.
203 // Set a flag to keep track of this corner case.
204 assert(holder->is_interface() || holder == SystemDictionary::Object_klass(), "unexpected holder class");
205 assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
206 change_to_virtual = true;
207
208 // ...and fall through as if we were handling invokevirtual:
209 }
210 case Bytecodes::_invokevirtual:
211 {
212 if (!is_vtable_call) {
213 assert(method->can_be_statically_bound(), "");
214 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
215 set_method_flags(as_TosState(method->result_type()),
216 ( 1 << is_vfinal_shift) |
217 ((method->is_final_method() ? 1 : 0) << is_final_shift) |
218 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
219 method()->size_of_parameters());
220 set_f2_as_vfinal_method(method());
221 } else {
222 assert(!method->can_be_statically_bound(), "");
223 assert(vtable_index >= 0, "valid index");
224 assert(!method->is_final_method(), "sanity");
225 set_method_flags(as_TosState(method->result_type()),
226 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
227 method()->size_of_parameters());
228 set_f2(vtable_index);
229 }
230 byte_no = 2;
231 break;
232 }
233
234 case Bytecodes::_invokespecial:
235 case Bytecodes::_invokestatic:
236 assert(!is_vtable_call, "");
237 // Note: Read and preserve the value of the is_vfinal flag on any
238 // invokevirtual bytecode shared with this constant pool cache entry.
239 // It is cheap and safe to consult is_vfinal() at all times.
240 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
241 set_method_flags(as_TosState(method->result_type()),
242 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
243 ((method->is_final_method() ? 1 : 0) << is_final_shift),
244 method()->size_of_parameters());
245 set_f1(method());
246 byte_no = 1;
247 break;
248 default:
249 ShouldNotReachHere();
250 break;
251 }
252
253 // Note: byte_no also appears in TemplateTable::resolve.
254 if (byte_no == 1) {
255 assert(invoke_code != Bytecodes::_invokevirtual &&
256 invoke_code != Bytecodes::_invokeinterface, "");
257 bool do_resolve = true;
258 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
259 // has to be checked that it is a subclass of the current class every time this bytecode
260 // is executed.
261 if (invoke_code == Bytecodes::_invokespecial && sender_is_interface &&
262 method->name() != vmSymbols::object_initializer_name()) {
263 do_resolve = false;
264 }
265 // Don't mark invokestatic to method as resolved if the holder class has not yet completed
266 // initialization. An invokestatic must only proceed if the class is initialized, but if
267 // we resolve it before then that class initialization check is skipped. However if the call
268 // is from the same class we can resolve as we must be executing with <clinit> on our call stack.
269 if (invoke_code == Bytecodes::_invokestatic) {
270 if (!UseFastClassInitChecks &&
271 !method->method_holder()->is_initialized() &&
272 method->method_holder() != pool_holder) {
273 do_resolve = false;
274 } else {
275 assert(method->method_holder()->is_initialized() ||
276 method->method_holder()->is_reentrant_initialization(Thread::current()),
277 "invalid class initialization state for invoke_static");
278 }
279 }
280 if (do_resolve) {
281 set_bytecode_1(invoke_code);
282 }
283 } else if (byte_no == 2) {
284 if (change_to_virtual) {
285 assert(invoke_code == Bytecodes::_invokeinterface, "");
286 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
287 //
288 // Workaround for the case where we encounter an invokeinterface, but we
289 // should really have an _invokevirtual since the resolved method is a
290 // virtual method in java.lang.Object. This is a corner case in the spec
291 // but is presumably legal. javac does not generate this code.
292 //
293 // We do not set bytecode_1() to _invokeinterface, because that is the
294 // bytecode # used by the interpreter to see if it is resolved. In this
295 // case, the method gets reresolved with caller for each interface call
296 // because the actual selected method may not be public.
297 //
298 // We set bytecode_2() to _invokevirtual.
299 // See also interpreterRuntime.cpp. (8/25/2000)
300 } else {
301 assert(invoke_code == Bytecodes::_invokevirtual ||
302 (invoke_code == Bytecodes::_invokeinterface &&
303 ((method->is_private() ||
304 (method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))),
305 "unexpected invocation mode");
306 if (invoke_code == Bytecodes::_invokeinterface &&
307 (method->is_private() || method->is_final())) {
308 // We set bytecode_1() to _invokeinterface, because that is the
309 // bytecode # used by the interpreter to see if it is resolved.
310 // We set bytecode_2() to _invokevirtual.
311 set_bytecode_1(invoke_code);
312 }
313 }
314 // set up for invokevirtual, even if linking for invokeinterface also:
315 set_bytecode_2(Bytecodes::_invokevirtual);
316 } else {
317 ShouldNotReachHere();
318 }
319 NOT_PRODUCT(verify(tty));
320 }
321
322 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
323 bool sender_is_interface, InstanceKlass* pool_holder) {
324 int index = Method::nonvirtual_vtable_index;
325 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
326 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface, pool_holder);
327 }
328
329 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
330 // either the method is a miranda or its holder should accept the given index
331 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
332 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
333 set_direct_or_vtable_call(invoke_code, method, index, false, NULL /* not used */);
334 }
335
336 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
337 Klass* referenced_klass,
338 const methodHandle& method, int index) {
339 assert(method->method_holder()->verify_itable_index(index), "");
340 assert(invoke_code == Bytecodes::_invokeinterface, "");
341 InstanceKlass* interf = method->method_holder();
342 assert(interf->is_interface(), "must be an interface");
343 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
344 set_f1(referenced_klass);
345 set_f2((intx)method());
346 set_method_flags(as_TosState(method->result_type()),
347 0, // no option bits
348 method()->size_of_parameters());
349 set_bytecode_1(Bytecodes::_invokeinterface);
350 }
351
352
353 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
354 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
355 }
356
357 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
358 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
359 }
360
361 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
362 Bytecodes::Code invoke_code,
363 const CallInfo &call_info) {
364 // NOTE: This CPCE can be the subject of data races.
365 // There are three words to update: flags, refs[f2], f1 (in that order).
366 // Writers must store all other values before f1.
367 // Readers must test f1 first for non-null before reading other fields.
368 // Competing writers must acquire exclusive access via a lock.
369 // A losing writer waits on the lock until the winner writes f1 and leaves
370 // the lock, so that when the losing writer returns, he can use the linked
371 // cache entry.
372
373 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
374 // Use the resolved_references() lock for this cpCache entry.
375 // resolved_references are created for all classes with Invokedynamic, MethodHandle
376 // or MethodType constant pool cache entries.
377 assert(resolved_references() != NULL,
378 "a resolved_references array should have been created for this class");
379 ObjectLocker ol(resolved_references, Thread::current());
380 if (!is_f1_null()) {
381 return;
382 }
383
384 if (indy_resolution_failed()) {
385 // Before we got here, another thread got a LinkageError exception during
386 // resolution. Ignore our success and throw their exception.
387 ConstantPoolCache* cpCache = cpool->cache();
388 int index = -1;
389 for (int i = 0; i < cpCache->length(); i++) {
390 if (cpCache->entry_at(i) == this) {
391 index = i;
392 break;
393 }
394 }
395 guarantee(index >= 0, "Didn't find cpCache entry!");
396 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
397 ConstantPool::encode_invokedynamic_index(index));
398 Thread* THREAD = Thread::current();
399 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
400 return;
401 }
402
403 const methodHandle adapter = call_info.resolved_method();
404 const Handle appendix = call_info.resolved_appendix();
405 const bool has_appendix = appendix.not_null();
406
407 // Write the flags.
408 // MHs and indy are always sig-poly and have a local signature.
409 set_method_flags(as_TosState(adapter->result_type()),
410 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
411 ( 1 << has_local_signature_shift ) |
412 ( 1 << is_final_shift ),
413 adapter->size_of_parameters());
414
415 if (TraceInvokeDynamic) {
416 ttyLocker ttyl;
417 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method=" PTR_FORMAT " (local signature) ",
418 invoke_code,
419 p2i(appendix()),
420 (has_appendix ? "" : " (unused)"),
421 p2i(adapter()));
422 adapter->print();
423 if (has_appendix) appendix()->print();
424 }
425
426 // Method handle invokes and invokedynamic sites use both cp cache words.
427 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
428 // In the general case, this could be the call site's MethodType,
429 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
430 // f1 contains the adapter method which manages the actual call.
431 // In the general case, this is a compiled LambdaForm.
432 // (The Java code is free to optimize these calls by binding other
433 // sorts of methods and appendices to call sites.)
434 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
435 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
436 // Even with the appendix, the method will never take more than 255 parameter slots.
437 //
438 // This means that given a call site like (List)mh.invoke("foo"),
439 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
440 // not '(Ljava/lang/String;)Ljava/util/List;'.
441 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
442 // This allows us to create fewer Methods, while keeping type safety.
443 //
444
445 // Store appendix, if any.
446 if (has_appendix) {
447 const int appendix_index = f2_as_index();
448 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
449 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
450 resolved_references->obj_at_put(appendix_index, appendix());
451 }
452
453 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
454
455 // The interpreter assembly code does not check byte_2,
456 // but it is used by is_resolved, method_if_resolved, etc.
457 set_bytecode_1(invoke_code);
458 NOT_PRODUCT(verify(tty));
459 if (TraceInvokeDynamic) {
460 ttyLocker ttyl;
461 this->print(tty, 0);
462 }
463
464 assert(has_appendix == this->has_appendix(), "proper storage of appendix flag");
465 assert(this->has_local_signature(), "proper storage of signature flag");
466 }
467
468 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
469 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
470
471 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
472 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
473 "No LinkageError exception");
474
475 // Use the resolved_references() lock for this cpCache entry.
476 // resolved_references are created for all classes with Invokedynamic, MethodHandle
477 // or MethodType constant pool cache entries.
478 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
479 assert(resolved_references() != NULL,
480 "a resolved_references array should have been created for this class");
481 ObjectLocker ol(resolved_references, THREAD);
482
483 // if f1 is not null or the indy_resolution_failed flag is set then another
484 // thread either succeeded in resolving the method or got a LinkageError
485 // exception, before this thread was able to record its failure. So, clear
486 // this thread's exception and return false so caller can use the earlier
487 // thread's result.
488 if (!is_f1_null() || indy_resolution_failed()) {
489 CLEAR_PENDING_EXCEPTION;
490 return false;
491 }
492
493 Symbol* error = PENDING_EXCEPTION->klass()->name();
494 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
495
496 SystemDictionary::add_resolution_error(cpool, index, error, message);
497 set_indy_resolution_failed();
498 return true;
499 }
500
501 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
502 // Decode the action of set_method and set_interface_call
503 Bytecodes::Code invoke_code = bytecode_1();
504 if (invoke_code != (Bytecodes::Code)0) {
505 Metadata* f1 = f1_ord();
506 if (f1 != NULL) {
507 switch (invoke_code) {
508 case Bytecodes::_invokeinterface:
509 assert(f1->is_klass(), "");
510 return f2_as_interface_method();
511 case Bytecodes::_invokestatic:
512 case Bytecodes::_invokespecial:
513 assert(!has_appendix(), "");
514 case Bytecodes::_invokehandle:
515 case Bytecodes::_invokedynamic:
516 assert(f1->is_method(), "");
517 return (Method*)f1;
518 default:
519 break;
520 }
521 }
522 }
523 invoke_code = bytecode_2();
524 if (invoke_code != (Bytecodes::Code)0) {
525 switch (invoke_code) {
526 case Bytecodes::_invokevirtual:
527 if (is_vfinal()) {
528 // invokevirtual
529 Method* m = f2_as_vfinal_method();
530 assert(m->is_method(), "");
531 return m;
532 } else {
533 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
534 if (cpool->tag_at(holder_index).is_klass()) {
535 Klass* klass = cpool->resolved_klass_at(holder_index);
536 return klass->method_at_vtable(f2_as_index());
537 }
538 }
539 break;
540 default:
541 break;
542 }
543 }
544 return NULL;
545 }
546
547
548 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
549 if (!has_appendix())
550 return NULL;
551 const int ref_index = f2_as_index();
552 objArrayOop resolved_references = cpool->resolved_references();
553 return resolved_references->obj_at(ref_index);
554 }
555
556
557 #if INCLUDE_JVMTI
558
559 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
560 if (log_is_enabled(Info, redefine, class, update)) {
561 ResourceMark rm;
562 if (!(*trace_name_printed)) {
563 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
564 *trace_name_printed = true;
565 }
566 log_debug(redefine, class, update, constantpool)
567 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string());
568 }
569 }
570
571 // RedefineClasses() API support:
572 // If this ConstantPoolCacheEntry refers to old_method then update it
573 // to refer to new_method.
574 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
575 Method* new_method, bool * trace_name_printed) {
576
577 if (is_vfinal()) {
578 // virtual and final so _f2 contains method ptr instead of vtable index
579 if (f2_as_vfinal_method() == old_method) {
580 // match old_method so need an update
581 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
582 _f2 = (intptr_t)new_method;
583 log_adjust("vfinal", old_method, new_method, trace_name_printed);
584 }
585 return;
586 }
587
588 assert (_f1 != NULL, "should not call with uninteresting entry");
589
590 if (!(_f1->is_method())) {
591 // _f1 is a Klass* for an interface, _f2 is the method
592 if (f2_as_interface_method() == old_method) {
593 _f2 = (intptr_t)new_method;
594 log_adjust("interface", old_method, new_method, trace_name_printed);
595 }
596 } else if (_f1 == old_method) {
597 _f1 = new_method;
598 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
599 }
600 }
601
602 // a constant pool cache entry should never contain old or obsolete methods
603 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
604 Method* m = get_interesting_method_entry();
605 // return false if m refers to a non-deleted old or obsolete method
606 if (m != NULL) {
607 assert(m->is_valid() && m->is_method(), "m is a valid method");
608 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
609 } else {
610 return true;
611 }
612 }
613
614 Method* ConstantPoolCacheEntry::get_interesting_method_entry() {
615 if (!is_method_entry()) {
616 // not a method entry so not interesting by default
617 return NULL;
618 }
619 Method* m = NULL;
620 if (is_vfinal()) {
621 // virtual and final so _f2 contains method ptr instead of vtable index
622 m = f2_as_vfinal_method();
623 } else if (is_f1_null()) {
624 // NULL _f1 means this is a virtual entry so also not interesting
625 return NULL;
626 } else {
627 if (!(_f1->is_method())) {
628 // _f1 is a Klass* for an interface
629 m = f2_as_interface_method();
630 } else {
631 m = f1_as_method();
632 }
633 }
634 assert(m != NULL && m->is_method(), "sanity check");
635 if (m == NULL || !m->is_method()) {
636 return NULL;
637 }
638 return m;
639 }
640 #endif // INCLUDE_JVMTI
641
642 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
643 // print separator
644 if (index == 0) st->print_cr(" -------------");
645 // print entry
646 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
647 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
648 constant_pool_index());
649 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
650 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
651 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
652 st->print_cr(" -------------");
653 }
654
655 void ConstantPoolCacheEntry::verify(outputStream* st) const {
656 // not implemented yet
657 }
658
659 // Implementation of ConstantPoolCache
660
661 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
662 const intStack& index_map,
663 const intStack& invokedynamic_index_map,
664 const intStack& invokedynamic_map, TRAPS) {
665
666 const int length = index_map.length() + invokedynamic_index_map.length();
667 int size = ConstantPoolCache::size(length);
668
669 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
670 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
671 }
672
673 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
674 const intArray& invokedynamic_inverse_index_map,
675 const intArray& invokedynamic_references_map) {
676 for (int i = 0; i < inverse_index_map.length(); i++) {
677 ConstantPoolCacheEntry* e = entry_at(i);
678 int original_index = inverse_index_map.at(i);
679 e->initialize_entry(original_index);
680 assert(entry_at(i) == e, "sanity");
681 }
682
683 // Append invokedynamic entries at the end
684 int invokedynamic_offset = inverse_index_map.length();
685 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
686 int offset = i + invokedynamic_offset;
687 ConstantPoolCacheEntry* e = entry_at(offset);
688 int original_index = invokedynamic_inverse_index_map.at(i);
689 e->initialize_entry(original_index);
690 assert(entry_at(offset) == e, "sanity");
691 }
692
693 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
694 const int cpci = invokedynamic_references_map.at(ref);
695 if (cpci >= 0) {
696 entry_at(cpci)->initialize_resolved_reference_index(ref);
697 }
698 }
699 }
700
701 void ConstantPoolCache::verify_just_initialized() {
702 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
703 }
704
705 void ConstantPoolCache::remove_unshareable_info() {
706 walk_entries_for_initialization(/*check_only = */ false);
707 }
708
709 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
710 assert(DumpSharedSpaces, "sanity");
711 // When dumping the archive, we want to clean up the ConstantPoolCache
712 // to remove any effect of linking due to the execution of Java code --
713 // each ConstantPoolCacheEntry will have the same contents as if
714 // ConstantPoolCache::initialize has just returned:
715 //
716 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
717 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
718 // - All other bits in the entries are cleared to zero.
719 ResourceMark rm;
720
721 InstanceKlass* ik = constant_pool()->pool_holder();
722 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
723 memset(f2_used, 0, sizeof(bool) * length());
724
725 // Find all the slots that we need to preserve f2
726 for (int i = 0; i < ik->methods()->length(); i++) {
727 Method* m = ik->methods()->at(i);
728 RawBytecodeStream bcs(m);
729 while (!bcs.is_last_bytecode()) {
730 Bytecodes::Code opcode = bcs.raw_next();
731 switch (opcode) {
732 case Bytecodes::_invokedynamic: {
733 int index = Bytes::get_native_u4(bcs.bcp() + 1);
734 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
735 f2_used[cp_cache_index] = 1;
736 }
737 break;
738 case Bytecodes::_invokehandle: {
739 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
740 f2_used[cp_cache_index] = 1;
741 }
742 break;
743 default:
744 break;
745 }
746 }
747 }
748
749 if (check_only) {
750 DEBUG_ONLY(
751 for (int i=0; i<length(); i++) {
752 entry_at(i)->verify_just_initialized(f2_used[i]);
753 })
754 } else {
755 for (int i=0; i<length(); i++) {
756 entry_at(i)->reinitialize(f2_used[i]);
757 }
758 }
759 }
760
761 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
762 assert(!is_shared(), "shared caches are not deallocated");
763 data->remove_handle(_resolved_references);
764 set_resolved_references(NULL);
765 MetadataFactory::free_array<u2>(data, _reference_map);
766 set_reference_map(NULL);
767 }
768
769 #if INCLUDE_CDS_JAVA_HEAP
770 oop ConstantPoolCache::archived_references() {
771 if (CompressedOops::is_null(_archived_references)) {
772 return NULL;
773 }
774 return HeapShared::materialize_archived_object(_archived_references);
775 }
776
777 void ConstantPoolCache::set_archived_references(oop o) {
778 assert(DumpSharedSpaces, "called only during runtime");
779 _archived_references = CompressedOops::encode(o);
780 }
781 #endif
782
783 #if INCLUDE_JVMTI
784 // RedefineClasses() API support:
785 // If any entry of this ConstantPoolCache points to any of
786 // old_methods, replace it with the corresponding new_method.
787 void ConstantPoolCache::adjust_method_entries(bool * trace_name_printed) {
788 for (int i = 0; i < length(); i++) {
789 ConstantPoolCacheEntry* entry = entry_at(i);
790 Method* old_method = entry->get_interesting_method_entry();
791 if (old_method == NULL || !old_method->is_old()) {
792 continue; // skip uninteresting entries
793 }
794 if (old_method->is_deleted()) {
795 // clean up entries with deleted methods
796 entry->initialize_entry(entry->constant_pool_index());
797 continue;
798 }
799 Method* new_method = old_method->get_new_method();
800 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
801 }
802 }
803
804 // the constant pool cache should never contain old or obsolete methods
805 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
806 for (int i = 1; i < length(); i++) {
807 if (entry_at(i)->get_interesting_method_entry() != NULL &&
808 !entry_at(i)->check_no_old_or_obsolete_entries()) {
809 return false;
810 }
811 }
812 return true;
813 }
814
815 void ConstantPoolCache::dump_cache() {
816 for (int i = 1; i < length(); i++) {
817 if (entry_at(i)->get_interesting_method_entry() != NULL) {
818 entry_at(i)->print(tty, i);
819 }
820 }
821 }
822 #endif // INCLUDE_JVMTI
823
824 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
825 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
826 it->push(&_constant_pool);
827 it->push(&_reference_map);
828 }
829
830 // Printing
831
832 void ConstantPoolCache::print_on(outputStream* st) const {
833 st->print_cr("%s", internal_name());
834 // print constant pool cache entries
835 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
836 }
837
838 void ConstantPoolCache::print_value_on(outputStream* st) const {
839 st->print("cache [%d]", length());
840 print_address_on(st);
841 st->print(" for ");
842 constant_pool()->print_value_on(st);
843 }
844
845
846 // Verification
847
848 void ConstantPoolCache::verify_on(outputStream* st) {
849 // print constant pool cache entries
850 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
851 }