1 /*
2 * Copyright (c) 1998, 2020, 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 "logging/logStream.hpp"
34 #include "memory/heapShared.hpp"
35 #include "memory/metadataFactory.hpp"
36 #include "memory/metaspaceClosure.hpp"
37 #include "memory/metaspaceShared.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "oops/access.inline.hpp"
40 #include "oops/compressedOops.hpp"
41 #include "oops/constantPool.inline.hpp"
42 #include "oops/cpCache.inline.hpp"
43 #include "oops/objArrayOop.inline.hpp"
44 #include "oops/oop.inline.hpp"
45 #include "prims/methodHandles.hpp"
46 #include "runtime/arguments.hpp"
47 #include "runtime/atomic.hpp"
48 #include "runtime/handles.inline.hpp"
49 #include "utilities/macros.hpp"
50
51 // Implementation of ConstantPoolCacheEntry
52
53 void ConstantPoolCacheEntry::initialize_entry(int index) {
54 assert(0 < index && index < 0x10000, "sanity check");
55 _indices = index;
56 _f1 = NULL;
57 _f2 = _flags = 0;
58 assert(constant_pool_index() == index, "");
59 }
60
61 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) {
62 assert((_indices & (~cp_index_mask)) == 0, "sanity");
63 assert(_f1 == NULL, "sanity");
64 assert(_flags == 0, "sanity");
65 if (!f2_used) {
66 assert(_f2 == 0, "sanity");
67 }
68 }
69
70 void ConstantPoolCacheEntry::reinitialize(bool f2_used) {
71 _indices &= cp_index_mask;
72 _f1 = NULL;
73 _flags = 0;
74 if (!f2_used) {
75 _f2 = 0;
76 }
77 }
78
79 int ConstantPoolCacheEntry::make_flags(TosState state,
80 int option_bits,
81 int field_index_or_method_params) {
82 assert(state < number_of_states, "Invalid state in make_flags");
83 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
84 // Preserve existing flag bit values
85 // The low bits are a field offset, or else the method parameter size.
86 #ifdef ASSERT
87 TosState old_state = flag_state();
88 assert(old_state == (TosState)0 || old_state == state,
89 "inconsistent cpCache flags state");
90 #endif
91 return (_flags | f) ;
92 }
93
94 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
95 #ifdef ASSERT
96 // Read once.
97 volatile Bytecodes::Code c = bytecode_1();
98 assert(c == 0 || c == code || code == 0, "update must be consistent");
99 #endif
100 // Need to flush pending stores here before bytecode is written.
101 Atomic::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift));
102 }
103
104 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
105 #ifdef ASSERT
106 // Read once.
107 volatile Bytecodes::Code c = bytecode_2();
108 assert(c == 0 || c == code || code == 0, "update must be consistent");
109 #endif
110 // Need to flush pending stores here before bytecode is written.
111 Atomic::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift));
112 }
113
114 // Sets f1, ordering with previous writes.
115 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
116 assert(f1 != NULL, "");
117 Atomic::release_store(&_f1, f1);
118 }
119
120 void ConstantPoolCacheEntry::set_indy_resolution_failed() {
121 Atomic::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift));
122 }
123
124 // Note that concurrent update of both bytecodes can leave one of them
125 // reset to zero. This is harmless; the interpreter will simply re-resolve
126 // the damaged entry. More seriously, the memory synchronization is needed
127 // to flush other fields (f1, f2) completely to memory before the bytecodes
128 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
129 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
130 Bytecodes::Code put_code,
131 Klass* field_holder,
132 int field_index,
133 int field_offset,
134 TosState field_type,
135 bool is_final,
136 bool is_volatile,
137 Klass* root_klass) {
138 set_f1(field_holder);
139 set_f2(field_offset);
140 assert((field_index & field_index_mask) == field_index,
141 "field index does not fit in low flag bits");
142 set_field_flags(field_type,
143 ((is_volatile ? 1 : 0) << is_volatile_shift) |
144 ((is_final ? 1 : 0) << is_final_shift),
145 field_index);
146 set_bytecode_1(get_code);
147 set_bytecode_2(put_code);
148 NOT_PRODUCT(verify(tty));
149 }
150
151 void ConstantPoolCacheEntry::set_parameter_size(int value) {
152 // This routine is called only in corner cases where the CPCE is not yet initialized.
153 // See AbstractInterpreter::deopt_continue_after_entry.
154 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
155 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
156 // Setting the parameter size by itself is only safe if the
157 // current value of _flags is 0, otherwise another thread may have
158 // updated it and we don't want to overwrite that value. Don't
159 // bother trying to update it once it's nonzero but always make
160 // sure that the final parameter size agrees with what was passed.
161 if (_flags == 0) {
162 intx newflags = (value & parameter_size_mask);
163 Atomic::cmpxchg(&_flags, (intx)0, newflags);
164 }
165 guarantee(parameter_size() == value,
166 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
167 }
168
169 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
170 const methodHandle& method,
171 int vtable_index,
172 bool sender_is_interface) {
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 if (invoke_code == Bytecodes::_invokestatic) {
266 assert(method->method_holder()->is_initialized() ||
267 method->method_holder()->is_reentrant_initialization(Thread::current()),
268 "invalid class initialization state for invoke_static");
269
270 if (!VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
271 // Don't mark invokestatic to method as resolved if the holder class has not yet completed
272 // initialization. An invokestatic must only proceed if the class is initialized, but if
273 // we resolve it before then that class initialization check is skipped.
274 //
275 // When fast class initialization checks are supported (VM_Version::supports_fast_class_init_checks() == true),
276 // template interpreter supports fast class initialization check for
277 // invokestatic which doesn't require call site re-resolution to
278 // enforce class initialization barrier.
279 do_resolve = false;
280 }
281 }
282 if (do_resolve) {
283 set_bytecode_1(invoke_code);
284 }
285 } else if (byte_no == 2) {
286 if (change_to_virtual) {
287 assert(invoke_code == Bytecodes::_invokeinterface, "");
288 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
289 //
290 // Workaround for the case where we encounter an invokeinterface, but we
291 // should really have an _invokevirtual since the resolved method is a
292 // virtual method in java.lang.Object. This is a corner case in the spec
293 // but is presumably legal. javac does not generate this code.
294 //
295 // We do not set bytecode_1() to _invokeinterface, because that is the
296 // bytecode # used by the interpreter to see if it is resolved. In this
297 // case, the method gets reresolved with caller for each interface call
298 // because the actual selected method may not be public.
299 //
300 // We set bytecode_2() to _invokevirtual.
301 // See also interpreterRuntime.cpp. (8/25/2000)
302 } else {
303 assert(invoke_code == Bytecodes::_invokevirtual ||
304 (invoke_code == Bytecodes::_invokeinterface &&
305 ((method->is_private() ||
306 (method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))),
307 "unexpected invocation mode");
308 if (invoke_code == Bytecodes::_invokeinterface &&
309 (method->is_private() || method->is_final())) {
310 // We set bytecode_1() to _invokeinterface, because that is the
311 // bytecode # used by the interpreter to see if it is resolved.
312 // We set bytecode_2() to _invokevirtual.
313 set_bytecode_1(invoke_code);
314 }
315 }
316 // set up for invokevirtual, even if linking for invokeinterface also:
317 set_bytecode_2(Bytecodes::_invokevirtual);
318 } else {
319 ShouldNotReachHere();
320 }
321 NOT_PRODUCT(verify(tty));
322 }
323
324 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
325 bool sender_is_interface) {
326 int index = Method::nonvirtual_vtable_index;
327 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
328 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
329 }
330
331 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
332 // either the method is a miranda or its holder should accept the given index
333 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
334 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
335 set_direct_or_vtable_call(invoke_code, method, index, false);
336 }
337
338 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
339 Klass* referenced_klass,
340 const methodHandle& method, int index) {
341 assert(method->method_holder()->verify_itable_index(index), "");
342 assert(invoke_code == Bytecodes::_invokeinterface, "");
343 InstanceKlass* interf = method->method_holder();
344 assert(interf->is_interface(), "must be an interface");
345 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
346 set_f1(referenced_klass);
347 set_f2((intx)method());
348 set_method_flags(as_TosState(method->result_type()),
349 0, // no option bits
350 method()->size_of_parameters());
351 set_bytecode_1(Bytecodes::_invokeinterface);
352 }
353
354
355 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
356 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
357 }
358
359 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
360 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
361 }
362
363 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
364 Bytecodes::Code invoke_code,
365 const CallInfo &call_info) {
366 // NOTE: This CPCE can be the subject of data races.
367 // There are three words to update: flags, refs[f2], f1 (in that order).
368 // Writers must store all other values before f1.
369 // Readers must test f1 first for non-null before reading other fields.
370 // Competing writers must acquire exclusive access via a lock.
371 // A losing writer waits on the lock until the winner writes f1 and leaves
372 // the lock, so that when the losing writer returns, he can use the linked
373 // cache entry.
374
375 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
376 // Use the resolved_references() lock for this cpCache entry.
377 // resolved_references are created for all classes with Invokedynamic, MethodHandle
378 // or MethodType constant pool cache entries.
379 assert(resolved_references() != NULL,
380 "a resolved_references array should have been created for this class");
381 ObjectLocker ol(resolved_references, Thread::current());
382 if (!is_f1_null()) {
383 return;
384 }
385
386 if (indy_resolution_failed()) {
387 // Before we got here, another thread got a LinkageError exception during
388 // resolution. Ignore our success and throw their exception.
389 ConstantPoolCache* cpCache = cpool->cache();
390 int index = -1;
391 for (int i = 0; i < cpCache->length(); i++) {
392 if (cpCache->entry_at(i) == this) {
393 index = i;
394 break;
395 }
396 }
397 guarantee(index >= 0, "Didn't find cpCache entry!");
398 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
399 ConstantPool::encode_invokedynamic_index(index));
400 Thread* THREAD = Thread::current();
401 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
402 return;
403 }
404
405 Method* adapter = call_info.resolved_method();
406 const Handle appendix = call_info.resolved_appendix();
407 const bool has_appendix = appendix.not_null();
408
409 // Write the flags.
410 // MHs and indy are always sig-poly and have a local signature.
411 set_method_flags(as_TosState(adapter->result_type()),
412 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
413 ( 1 << has_local_signature_shift ) |
414 ( 1 << is_final_shift ),
415 adapter->size_of_parameters());
416
417 LogStream* log_stream = NULL;
418 LogStreamHandle(Debug, methodhandles, indy) lsh_indy;
419 if (lsh_indy.is_enabled()) {
420 ResourceMark rm;
421 log_stream = &lsh_indy;
422 log_stream->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method=" PTR_FORMAT " (local signature) ",
423 invoke_code,
424 p2i(appendix()),
425 (has_appendix ? "" : " (unused)"),
426 p2i(adapter));
427 adapter->print_on(log_stream);
428 if (has_appendix) appendix()->print_on(log_stream);
429 }
430
431 // Method handle invokes and invokedynamic sites use both cp cache words.
432 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
433 // In the general case, this could be the call site's MethodType,
434 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
435 // f1 contains the adapter method which manages the actual call.
436 // In the general case, this is a compiled LambdaForm.
437 // (The Java code is free to optimize these calls by binding other
438 // sorts of methods and appendices to call sites.)
439 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
440 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
441 // Even with the appendix, the method will never take more than 255 parameter slots.
442 //
443 // This means that given a call site like (List)mh.invoke("foo"),
444 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
445 // not '(Ljava/lang/String;)Ljava/util/List;'.
446 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
447 // This allows us to create fewer Methods, while keeping type safety.
448 //
449
450 // Store appendix, if any.
451 if (has_appendix) {
452 const int appendix_index = f2_as_index();
453 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
454 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
455 resolved_references->obj_at_put(appendix_index, appendix());
456 }
457
458 release_set_f1(adapter); // This must be the last one to set (see NOTE above)!
459
460 // The interpreter assembly code does not check byte_2,
461 // but it is used by is_resolved, method_if_resolved, etc.
462 set_bytecode_1(invoke_code);
463 NOT_PRODUCT(verify(tty));
464
465 if (log_stream != NULL) {
466 this->print(log_stream, 0);
467 }
468
469 assert(has_appendix == this->has_appendix(), "proper storage of appendix flag");
470 assert(this->has_local_signature(), "proper storage of signature flag");
471 }
472
473 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
474 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
475
476 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
477 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
478 "No LinkageError exception");
479
480 // Use the resolved_references() lock for this cpCache entry.
481 // resolved_references are created for all classes with Invokedynamic, MethodHandle
482 // or MethodType constant pool cache entries.
483 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
484 assert(resolved_references() != NULL,
485 "a resolved_references array should have been created for this class");
486 ObjectLocker ol(resolved_references, THREAD);
487
488 // if f1 is not null or the indy_resolution_failed flag is set then another
489 // thread either succeeded in resolving the method or got a LinkageError
490 // exception, before this thread was able to record its failure. So, clear
491 // this thread's exception and return false so caller can use the earlier
492 // thread's result.
493 if (!is_f1_null() || indy_resolution_failed()) {
494 CLEAR_PENDING_EXCEPTION;
495 return false;
496 }
497
498 Symbol* error = PENDING_EXCEPTION->klass()->name();
499 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
500
501 SystemDictionary::add_resolution_error(cpool, index, error, message);
502 set_indy_resolution_failed();
503 return true;
504 }
505
506 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
507 // Decode the action of set_method and set_interface_call
508 Bytecodes::Code invoke_code = bytecode_1();
509 if (invoke_code != (Bytecodes::Code)0) {
510 Metadata* f1 = f1_ord();
511 if (f1 != NULL) {
512 switch (invoke_code) {
513 case Bytecodes::_invokeinterface:
514 assert(f1->is_klass(), "");
515 return f2_as_interface_method();
516 case Bytecodes::_invokestatic:
517 case Bytecodes::_invokespecial:
518 assert(!has_appendix(), "");
519 case Bytecodes::_invokehandle:
520 case Bytecodes::_invokedynamic:
521 assert(f1->is_method(), "");
522 return (Method*)f1;
523 default:
524 break;
525 }
526 }
527 }
528 invoke_code = bytecode_2();
529 if (invoke_code != (Bytecodes::Code)0) {
530 switch (invoke_code) {
531 case Bytecodes::_invokevirtual:
532 if (is_vfinal()) {
533 // invokevirtual
534 Method* m = f2_as_vfinal_method();
535 assert(m->is_method(), "");
536 return m;
537 } else {
538 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
539 if (cpool->tag_at(holder_index).is_klass()) {
540 Klass* klass = cpool->resolved_klass_at(holder_index);
541 return klass->method_at_vtable(f2_as_index());
542 }
543 }
544 break;
545 default:
546 break;
547 }
548 }
549 return NULL;
550 }
551
552
553 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
554 if (!has_appendix())
555 return NULL;
556 const int ref_index = f2_as_index();
557 objArrayOop resolved_references = cpool->resolved_references();
558 return resolved_references->obj_at(ref_index);
559 }
560
561
562 #if INCLUDE_JVMTI
563
564 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
565 ResourceMark rm;
566
567 if (!(*trace_name_printed)) {
568 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
569 *trace_name_printed = true;
570 }
571 log_trace(redefine, class, update, constantpool)
572 ("cpc %s entry update: %s", entry_type, new_method->external_name());
573 }
574
575 // RedefineClasses() API support:
576 // If this ConstantPoolCacheEntry refers to old_method then update it
577 // to refer to new_method.
578 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
579 Method* new_method, bool * trace_name_printed) {
580
581 if (is_vfinal()) {
582 // virtual and final so _f2 contains method ptr instead of vtable index
583 if (f2_as_vfinal_method() == old_method) {
584 // match old_method so need an update
585 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
586 _f2 = (intptr_t)new_method;
587 log_adjust("vfinal", old_method, new_method, trace_name_printed);
588 }
589 return;
590 }
591
592 assert (_f1 != NULL, "should not call with uninteresting entry");
593
594 if (!(_f1->is_method())) {
595 // _f1 is a Klass* for an interface, _f2 is the method
596 if (f2_as_interface_method() == old_method) {
597 _f2 = (intptr_t)new_method;
598 log_adjust("interface", old_method, new_method, trace_name_printed);
599 }
600 } else if (_f1 == old_method) {
601 _f1 = new_method;
602 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
603 }
604 }
605
606 // a constant pool cache entry should never contain old or obsolete methods
607 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
608 Method* m = get_interesting_method_entry();
609 // return false if m refers to a non-deleted old or obsolete method
610 if (m != NULL) {
611 assert(m->is_valid() && m->is_method(), "m is a valid method");
612 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
613 } else {
614 return true;
615 }
616 }
617
618 Method* ConstantPoolCacheEntry::get_interesting_method_entry() {
619 if (!is_method_entry()) {
620 // not a method entry so not interesting by default
621 return NULL;
622 }
623 Method* m = NULL;
624 if (is_vfinal()) {
625 // virtual and final so _f2 contains method ptr instead of vtable index
626 m = f2_as_vfinal_method();
627 } else if (is_f1_null()) {
628 // NULL _f1 means this is a virtual entry so also not interesting
629 return NULL;
630 } else {
631 if (!(_f1->is_method())) {
632 // _f1 is a Klass* for an interface
633 m = f2_as_interface_method();
634 } else {
635 m = f1_as_method();
636 }
637 }
638 assert(m != NULL && m->is_method(), "sanity check");
639 if (m == NULL || !m->is_method()) {
640 return NULL;
641 }
642 return m;
643 }
644 #endif // INCLUDE_JVMTI
645
646 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
647 // print separator
648 if (index == 0) st->print_cr(" -------------");
649 // print entry
650 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
651 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
652 constant_pool_index());
653 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
654 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
655 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
656 st->print_cr(" -------------");
657 }
658
659 void ConstantPoolCacheEntry::verify(outputStream* st) const {
660 // not implemented yet
661 }
662
663 // Implementation of ConstantPoolCache
664
665 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
666 const intStack& index_map,
667 const intStack& invokedynamic_index_map,
668 const intStack& invokedynamic_map, TRAPS) {
669
670 const int length = index_map.length() + invokedynamic_index_map.length();
671 int size = ConstantPoolCache::size(length);
672
673 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
674 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
675 }
676
677 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
678 const intArray& invokedynamic_inverse_index_map,
679 const intArray& invokedynamic_references_map) {
680 for (int i = 0; i < inverse_index_map.length(); i++) {
681 ConstantPoolCacheEntry* e = entry_at(i);
682 int original_index = inverse_index_map.at(i);
683 e->initialize_entry(original_index);
684 assert(entry_at(i) == e, "sanity");
685 }
686
687 // Append invokedynamic entries at the end
688 int invokedynamic_offset = inverse_index_map.length();
689 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
690 int offset = i + invokedynamic_offset;
691 ConstantPoolCacheEntry* e = entry_at(offset);
692 int original_index = invokedynamic_inverse_index_map.at(i);
693 e->initialize_entry(original_index);
694 assert(entry_at(offset) == e, "sanity");
695 }
696
697 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
698 const int cpci = invokedynamic_references_map.at(ref);
699 if (cpci >= 0) {
700 entry_at(cpci)->initialize_resolved_reference_index(ref);
701 }
702 }
703 }
704
705 void ConstantPoolCache::verify_just_initialized() {
706 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
707 }
708
709 void ConstantPoolCache::remove_unshareable_info() {
710 walk_entries_for_initialization(/*check_only = */ false);
711 }
712
713 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
714 Arguments::assert_is_dumping_archive();
715 // When dumping the archive, we want to clean up the ConstantPoolCache
716 // to remove any effect of linking due to the execution of Java code --
717 // each ConstantPoolCacheEntry will have the same contents as if
718 // ConstantPoolCache::initialize has just returned:
719 //
720 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
721 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
722 // - All other bits in the entries are cleared to zero.
723 ResourceMark rm;
724
725 InstanceKlass* ik = constant_pool()->pool_holder();
726 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
727 memset(f2_used, 0, sizeof(bool) * length());
728
729 Thread* THREAD = Thread::current();
730
731 // Find all the slots that we need to preserve f2
732 for (int i = 0; i < ik->methods()->length(); i++) {
733 Method* m = ik->methods()->at(i);
734 RawBytecodeStream bcs(methodHandle(THREAD, m));
735 while (!bcs.is_last_bytecode()) {
736 Bytecodes::Code opcode = bcs.raw_next();
737 switch (opcode) {
738 case Bytecodes::_invokedynamic: {
739 int index = Bytes::get_native_u4(bcs.bcp() + 1);
740 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
741 f2_used[cp_cache_index] = 1;
742 }
743 break;
744 case Bytecodes::_invokehandle: {
745 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
746 f2_used[cp_cache_index] = 1;
747 }
748 break;
749 default:
750 break;
751 }
752 }
753 }
754
755 if (check_only) {
756 DEBUG_ONLY(
757 for (int i=0; i<length(); i++) {
758 entry_at(i)->verify_just_initialized(f2_used[i]);
759 })
760 } else {
761 for (int i=0; i<length(); i++) {
762 entry_at(i)->reinitialize(f2_used[i]);
763 }
764 }
765 }
766
767 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
768 assert(!is_shared(), "shared caches are not deallocated");
769 data->remove_handle(_resolved_references);
770 set_resolved_references(OopHandle());
771 MetadataFactory::free_array<u2>(data, _reference_map);
772 set_reference_map(NULL);
773 }
774
775 #if INCLUDE_CDS_JAVA_HEAP
776 oop ConstantPoolCache::archived_references() {
777 if (_archived_references_index < 0) {
778 return NULL;
779 }
780 return HeapShared::get_root(_archived_references_index);
781 }
782
783 void ConstantPoolCache::clear_archived_references() {
784 if (_archived_references_index >= 0) {
785 HeapShared::clear_root(_archived_references_index);
786 _archived_references_index = -1;
787 }
788 }
789
790 void ConstantPoolCache::set_archived_references(oop o) {
791 assert(DumpSharedSpaces, "called only during runtime");
792 _archived_references_index = HeapShared::append_root(o);
793 }
794 #endif
795
796 #if INCLUDE_JVMTI
797 // RedefineClasses() API support:
798 // If any entry of this ConstantPoolCache points to any of
799 // old_methods, replace it with the corresponding new_method.
800 void ConstantPoolCache::adjust_method_entries(bool * trace_name_printed) {
801 for (int i = 0; i < length(); i++) {
802 ConstantPoolCacheEntry* entry = entry_at(i);
803 Method* old_method = entry->get_interesting_method_entry();
804 if (old_method == NULL || !old_method->is_old()) {
805 continue; // skip uninteresting entries
806 }
807 if (old_method->is_deleted()) {
808 // clean up entries with deleted methods
809 entry->initialize_entry(entry->constant_pool_index());
810 continue;
811 }
812 Method* new_method = old_method->get_new_method();
813 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
814 }
815 }
816
817 // the constant pool cache should never contain old or obsolete methods
818 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
819 ResourceMark rm;
820 for (int i = 1; i < length(); i++) {
821 Method* m = entry_at(i)->get_interesting_method_entry();
822 if (m != NULL && !entry_at(i)->check_no_old_or_obsolete_entries()) {
823 log_trace(redefine, class, update, constantpool)
824 ("cpcache check found old method entry: class: %s, old: %d, obsolete: %d, method: %s",
825 constant_pool()->pool_holder()->external_name(), m->is_old(), m->is_obsolete(), m->external_name());
826 return false;
827 }
828 }
829 return true;
830 }
831
832 void ConstantPoolCache::dump_cache() {
833 for (int i = 1; i < length(); i++) {
834 if (entry_at(i)->get_interesting_method_entry() != NULL) {
835 entry_at(i)->print(tty, i);
836 }
837 }
838 }
839 #endif // INCLUDE_JVMTI
840
841 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
842 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
843 it->push(&_constant_pool);
844 it->push(&_reference_map);
845 }
846
847 // Printing
848
849 void ConstantPoolCache::print_on(outputStream* st) const {
850 st->print_cr("%s", internal_name());
851 // print constant pool cache entries
852 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
853 }
854
855 void ConstantPoolCache::print_value_on(outputStream* st) const {
856 st->print("cache [%d]", length());
857 print_address_on(st);
858 st->print(" for ");
859 constant_pool()->print_value_on(st);
860 }
861
862
863 // Verification
864
865 void ConstantPoolCache::verify_on(outputStream* st) {
866 // print constant pool cache entries
867 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
868 }