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 "oops/access.inline.hpp"
39 #include "oops/compressedOops.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 "utilities/macros.hpp"
48
49 // Implementation of ConstantPoolCacheEntry
50
51 void ConstantPoolCacheEntry::initialize_entry(int index) {
52 assert(0 < index && index < 0x10000, "sanity check");
53 _indices = index;
54 _f1 = NULL;
55 _f2 = _flags = 0;
56 assert(constant_pool_index() == index, "");
57 }
58
59 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) {
60 assert((_indices & (~cp_index_mask)) == 0, "sanity");
61 assert(_f1 == NULL, "sanity");
62 assert(_flags == 0, "sanity");
63 if (!f2_used) {
64 assert(_f2 == 0, "sanity");
65 }
66 }
67
68 void ConstantPoolCacheEntry::reinitialize(bool f2_used) {
69 _indices &= cp_index_mask;
70 _f1 = NULL;
71 _flags = 0;
72 if (!f2_used) {
73 _f2 = 0;
74 }
75 }
76
77 int ConstantPoolCacheEntry::make_flags(TosState state,
78 int option_bits,
79 int field_index_or_method_params) {
80 assert(state < number_of_states, "Invalid state in make_flags");
81 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
82 // Preserve existing flag bit values
83 // The low bits are a field offset, or else the method parameter size.
84 #ifdef ASSERT
85 TosState old_state = flag_state();
86 assert(old_state == (TosState)0 || old_state == state,
87 "inconsistent cpCache flags state");
88 #endif
89 return (_flags | f) ;
90 }
91
92 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
93 #ifdef ASSERT
94 // Read once.
95 volatile Bytecodes::Code c = bytecode_1();
96 assert(c == 0 || c == code || code == 0, "update must be consistent");
97 #endif
98 // Need to flush pending stores here before bytecode is written.
99 Atomic::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift));
100 }
101
102 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
103 #ifdef ASSERT
104 // Read once.
105 volatile Bytecodes::Code c = bytecode_2();
106 assert(c == 0 || c == code || code == 0, "update must be consistent");
107 #endif
108 // Need to flush pending stores here before bytecode is written.
109 Atomic::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift));
110 }
111
112 // Sets f1, ordering with previous writes.
113 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
114 assert(f1 != NULL, "");
115 Atomic::release_store(&_f1, f1);
116 }
117
118 void ConstantPoolCacheEntry::set_indy_resolution_failed() {
119 Atomic::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift));
120 }
121
122 // Note that concurrent update of both bytecodes can leave one of them
123 // reset to zero. This is harmless; the interpreter will simply re-resolve
124 // the damaged entry. More seriously, the memory synchronization is needed
125 // to flush other fields (f1, f2) completely to memory before the bytecodes
126 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
127 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
128 Bytecodes::Code put_code,
129 Klass* field_holder,
130 int field_index,
131 int field_offset,
132 TosState field_type,
133 bool is_final,
134 bool is_volatile,
135 Klass* root_klass) {
136 set_f1(field_holder);
137 set_f2(field_offset);
138 assert((field_index & field_index_mask) == field_index,
139 "field index does not fit in low flag bits");
140 set_field_flags(field_type,
141 ((is_volatile ? 1 : 0) << is_volatile_shift) |
142 ((is_final ? 1 : 0) << is_final_shift),
143 field_index);
144 set_bytecode_1(get_code);
145 set_bytecode_2(put_code);
146 NOT_PRODUCT(verify(tty));
147 }
148
149 void ConstantPoolCacheEntry::set_parameter_size(int value) {
150 // This routine is called only in corner cases where the CPCE is not yet initialized.
151 // See AbstractInterpreter::deopt_continue_after_entry.
152 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
153 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
154 // Setting the parameter size by itself is only safe if the
155 // current value of _flags is 0, otherwise another thread may have
156 // updated it and we don't want to overwrite that value. Don't
157 // bother trying to update it once it's nonzero but always make
158 // sure that the final parameter size agrees with what was passed.
159 if (_flags == 0) {
160 intx newflags = (value & parameter_size_mask);
161 Atomic::cmpxchg(&_flags, (intx)0, newflags);
162 }
163 guarantee(parameter_size() == value,
164 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
165 }
166
167 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
168 const methodHandle& method,
169 int vtable_index,
170 bool sender_is_interface) {
171 bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean
172 assert(method->interpreter_entry() != NULL, "should have been set at this point");
173 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
174
175 int byte_no = -1;
176 bool change_to_virtual = false;
177 InstanceKlass* holder = NULL; // have to declare this outside the switch
178 switch (invoke_code) {
179 case Bytecodes::_invokeinterface:
180 holder = method->method_holder();
181 // check for private interface method invocations
182 if (vtable_index == Method::nonvirtual_vtable_index && holder->is_interface() ) {
183 assert(method->is_private(), "unexpected non-private method");
184 assert(method->can_be_statically_bound(), "unexpected non-statically-bound method");
185 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
186 set_method_flags(as_TosState(method->result_type()),
187 ( 1 << is_vfinal_shift) |
188 ((method->is_final_method() ? 1 : 0) << is_final_shift),
189 method()->size_of_parameters());
190 set_f2_as_vfinal_method(method());
191 byte_no = 2;
192 set_f1(holder); // interface klass*
193 break;
194 }
195 else {
196 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
197 // instruction links to a non-interface method (in Object). This can happen when
198 // an interface redeclares an Object method (like CharSequence declaring toString())
199 // or when invokeinterface is used explicitly.
200 // In that case, the method has no itable index and must be invoked as a virtual.
201 // Set a flag to keep track of this corner case.
202 assert(holder->is_interface() || holder == SystemDictionary::Object_klass(), "unexpected holder class");
203 assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
204 change_to_virtual = true;
205
206 // ...and fall through as if we were handling invokevirtual:
207 }
208 case Bytecodes::_invokevirtual:
209 {
210 if (!is_vtable_call) {
211 assert(method->can_be_statically_bound(), "");
212 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
213 set_method_flags(as_TosState(method->result_type()),
214 ( 1 << is_vfinal_shift) |
215 ((method->is_final_method() ? 1 : 0) << is_final_shift) |
216 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
217 method()->size_of_parameters());
218 set_f2_as_vfinal_method(method());
219 } else {
220 assert(!method->can_be_statically_bound(), "");
221 assert(vtable_index >= 0, "valid index");
222 assert(!method->is_final_method(), "sanity");
223 set_method_flags(as_TosState(method->result_type()),
224 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
225 method()->size_of_parameters());
226 set_f2(vtable_index);
227 }
228 byte_no = 2;
229 break;
230 }
231
232 case Bytecodes::_invokespecial:
233 case Bytecodes::_invokestatic:
234 assert(!is_vtable_call, "");
235 // Note: Read and preserve the value of the is_vfinal flag on any
236 // invokevirtual bytecode shared with this constant pool cache entry.
237 // It is cheap and safe to consult is_vfinal() at all times.
238 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
239 set_method_flags(as_TosState(method->result_type()),
240 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
241 ((method->is_final_method() ? 1 : 0) << is_final_shift),
242 method()->size_of_parameters());
243 set_f1(method());
244 byte_no = 1;
245 break;
246 default:
247 ShouldNotReachHere();
248 break;
249 }
250
251 // Note: byte_no also appears in TemplateTable::resolve.
252 if (byte_no == 1) {
253 assert(invoke_code != Bytecodes::_invokevirtual &&
254 invoke_code != Bytecodes::_invokeinterface, "");
255 bool do_resolve = true;
256 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
257 // has to be checked that it is a subclass of the current class every time this bytecode
258 // is executed.
259 if (invoke_code == Bytecodes::_invokespecial && sender_is_interface &&
260 method->name() != vmSymbols::object_initializer_name()) {
261 do_resolve = false;
262 }
263 if (invoke_code == Bytecodes::_invokestatic) {
264 assert(method->method_holder()->is_initialized() ||
265 method->method_holder()->is_reentrant_initialization(Thread::current()),
266 "invalid class initialization state for invoke_static");
267
268 if (!VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
269 // Don't mark invokestatic to method as resolved if the holder class has not yet completed
270 // initialization. An invokestatic must only proceed if the class is initialized, but if
271 // we resolve it before then that class initialization check is skipped.
272 //
273 // When fast class initialization checks are supported (VM_Version::supports_fast_class_init_checks() == true),
274 // template interpreter supports fast class initialization check for
275 // invokestatic which doesn't require call site re-resolution to
276 // enforce class initialization barrier.
277 do_resolve = false;
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) {
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);
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);
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 Method* 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 Arguments::assert_is_dumping_archive();
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 Thread* THREAD = Thread::current();
726
727 // Find all the slots that we need to preserve f2
728 for (int i = 0; i < ik->methods()->length(); i++) {
729 Method* m = ik->methods()->at(i);
730 RawBytecodeStream bcs(methodHandle(THREAD, m));
731 while (!bcs.is_last_bytecode()) {
732 Bytecodes::Code opcode = bcs.raw_next();
733 switch (opcode) {
734 case Bytecodes::_invokedynamic: {
735 int index = Bytes::get_native_u4(bcs.bcp() + 1);
736 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
737 f2_used[cp_cache_index] = 1;
738 }
739 break;
740 case Bytecodes::_invokehandle: {
741 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
742 f2_used[cp_cache_index] = 1;
743 }
744 break;
745 default:
746 break;
747 }
748 }
749 }
750
751 if (check_only) {
752 DEBUG_ONLY(
753 for (int i=0; i<length(); i++) {
754 entry_at(i)->verify_just_initialized(f2_used[i]);
755 })
756 } else {
757 for (int i=0; i<length(); i++) {
758 entry_at(i)->reinitialize(f2_used[i]);
759 }
760 }
761 }
762
763 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
764 assert(!is_shared(), "shared caches are not deallocated");
765 data->remove_handle(_resolved_references);
766 set_resolved_references(NULL);
767 MetadataFactory::free_array<u2>(data, _reference_map);
768 set_reference_map(NULL);
769 }
770
771 #if INCLUDE_CDS_JAVA_HEAP
772 oop ConstantPoolCache::archived_references() {
773 if (CompressedOops::is_null(_archived_references)) {
774 return NULL;
775 }
776 return HeapShared::materialize_archived_object(_archived_references);
777 }
778
779 void ConstantPoolCache::set_archived_references(oop o) {
780 assert(DumpSharedSpaces, "called only during runtime");
781 _archived_references = CompressedOops::encode(o);
782 }
783 #endif
784
785 #if INCLUDE_JVMTI
786 // RedefineClasses() API support:
787 // If any entry of this ConstantPoolCache points to any of
788 // old_methods, replace it with the corresponding new_method.
789 void ConstantPoolCache::adjust_method_entries(bool * trace_name_printed) {
790 for (int i = 0; i < length(); i++) {
791 ConstantPoolCacheEntry* entry = entry_at(i);
792 Method* old_method = entry->get_interesting_method_entry();
793 if (old_method == NULL || !old_method->is_old()) {
794 continue; // skip uninteresting entries
795 }
796 if (old_method->is_deleted()) {
797 // clean up entries with deleted methods
798 entry->initialize_entry(entry->constant_pool_index());
799 continue;
800 }
801 Method* new_method = old_method->get_new_method();
802 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
803 }
804 }
805
806 // the constant pool cache should never contain old or obsolete methods
807 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
808 for (int i = 1; i < length(); i++) {
809 if (entry_at(i)->get_interesting_method_entry() != NULL &&
810 !entry_at(i)->check_no_old_or_obsolete_entries()) {
811 return false;
812 }
813 }
814 return true;
815 }
816
817 void ConstantPoolCache::dump_cache() {
818 for (int i = 1; i < length(); i++) {
819 if (entry_at(i)->get_interesting_method_entry() != NULL) {
820 entry_at(i)->print(tty, i);
821 }
822 }
823 }
824 #endif // INCLUDE_JVMTI
825
826 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
827 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
828 it->push(&_constant_pool);
829 it->push(&_reference_map);
830 }
831
832 // Printing
833
834 void ConstantPoolCache::print_on(outputStream* st) const {
835 st->print_cr("%s", internal_name());
836 // print constant pool cache entries
837 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
838 }
839
840 void ConstantPoolCache::print_value_on(outputStream* st) const {
841 st->print("cache [%d]", length());
842 print_address_on(st);
843 st->print(" for ");
844 constant_pool()->print_value_on(st);
845 }
846
847
848 // Verification
849
850 void ConstantPoolCache::verify_on(outputStream* st) {
851 // print constant pool cache entries
852 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
853 }