1 /*
2 * Copyright (c) 1998, 2018, 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/metadataFactory.hpp"
34 #include "memory/metaspaceClosure.hpp"
35 #include "memory/metaspaceShared.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "memory/universe.hpp"
38 #include "oops/access.inline.hpp"
39 #include "oops/constantPool.inline.hpp"
40 #include "oops/cpCache.inline.hpp"
41 #include "oops/objArrayOop.inline.hpp"
42 #include "oops/oop.inline.hpp"
43 #include "prims/methodHandles.hpp"
44 #include "runtime/atomic.hpp"
45 #include "runtime/handles.inline.hpp"
46 #include "runtime/orderAccess.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 OrderAccess::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 OrderAccess::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 OrderAccess::release_store(&_f1, f1);
116 }
117
118 void ConstantPoolCacheEntry::set_indy_resolution_failed() {
119 OrderAccess::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(newflags, &_flags, (intx)0);
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 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
256 // has to be checked that it is a subclass of the current class every time this bytecode
257 // is executed.
258 if (invoke_code != Bytecodes::_invokespecial || !sender_is_interface ||
259 method->name() == vmSymbols::object_initializer_name()) {
260 set_bytecode_1(invoke_code);
261 }
262 } else if (byte_no == 2) {
263 if (change_to_virtual) {
264 assert(invoke_code == Bytecodes::_invokeinterface, "");
265 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
266 //
267 // Workaround for the case where we encounter an invokeinterface, but we
268 // should really have an _invokevirtual since the resolved method is a
269 // virtual method in java.lang.Object. This is a corner case in the spec
270 // but is presumably legal. javac does not generate this code.
271 //
272 // We do not set bytecode_1() to _invokeinterface, because that is the
273 // bytecode # used by the interpreter to see if it is resolved. In this
274 // case, the method gets reresolved with caller for each interface call
275 // because the actual selected method may not be public.
276 //
277 // We set bytecode_2() to _invokevirtual.
278 // See also interpreterRuntime.cpp. (8/25/2000)
279 } else {
280 assert(invoke_code == Bytecodes::_invokevirtual ||
281 (invoke_code == Bytecodes::_invokeinterface &&
282 ((method->is_private() ||
283 (method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))),
284 "unexpected invocation mode");
285 if (invoke_code == Bytecodes::_invokeinterface &&
286 (method->is_private() || method->is_final())) {
287 // We set bytecode_1() to _invokeinterface, because that is the
288 // bytecode # used by the interpreter to see if it is resolved.
289 // We set bytecode_2() to _invokevirtual.
290 set_bytecode_1(invoke_code);
291 }
292 }
293 // set up for invokevirtual, even if linking for invokeinterface also:
294 set_bytecode_2(Bytecodes::_invokevirtual);
295 } else {
296 ShouldNotReachHere();
297 }
298 NOT_PRODUCT(verify(tty));
299 }
300
301 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
302 bool sender_is_interface) {
303 int index = Method::nonvirtual_vtable_index;
304 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
305 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
306 }
307
308 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
309 // either the method is a miranda or its holder should accept the given index
310 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
311 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
312 set_direct_or_vtable_call(invoke_code, method, index, false);
313 }
314
315 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
316 Klass* referenced_klass,
317 const methodHandle& method, int index) {
318 assert(method->method_holder()->verify_itable_index(index), "");
319 assert(invoke_code == Bytecodes::_invokeinterface, "");
320 InstanceKlass* interf = method->method_holder();
321 assert(interf->is_interface(), "must be an interface");
322 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
323 set_f1(referenced_klass);
324 set_f2((intx)method());
325 set_method_flags(as_TosState(method->result_type()),
326 0, // no option bits
327 method()->size_of_parameters());
328 set_bytecode_1(Bytecodes::_invokeinterface);
329 }
330
331
332 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
333 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
334 }
335
336 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
337 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
338 }
339
340 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
341 Bytecodes::Code invoke_code,
342 const CallInfo &call_info) {
343 // NOTE: This CPCE can be the subject of data races.
344 // There are three words to update: flags, refs[f2], f1 (in that order).
345 // Writers must store all other values before f1.
346 // Readers must test f1 first for non-null before reading other fields.
347 // Competing writers must acquire exclusive access via a lock.
348 // A losing writer waits on the lock until the winner writes f1 and leaves
349 // the lock, so that when the losing writer returns, he can use the linked
350 // cache entry.
351
352 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
353 // Use the resolved_references() lock for this cpCache entry.
354 // resolved_references are created for all classes with Invokedynamic, MethodHandle
355 // or MethodType constant pool cache entries.
356 assert(resolved_references() != NULL,
357 "a resolved_references array should have been created for this class");
358 ObjectLocker ol(resolved_references, Thread::current());
359 if (!is_f1_null()) {
360 return;
361 }
362
363 if (indy_resolution_failed()) {
364 // Before we got here, another thread got a LinkageError exception during
365 // resolution. Ignore our success and throw their exception.
366 ConstantPoolCache* cpCache = cpool->cache();
367 int index = -1;
368 for (int i = 0; i < cpCache->length(); i++) {
369 if (cpCache->entry_at(i) == this) {
370 index = i;
371 break;
372 }
373 }
374 guarantee(index >= 0, "Didn't find cpCache entry!");
375 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
376 ConstantPool::encode_invokedynamic_index(index));
377 Thread* THREAD = Thread::current();
378 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
379 return;
380 }
381
382 const methodHandle adapter = call_info.resolved_method();
383 const Handle appendix = call_info.resolved_appendix();
384 const Handle method_type = call_info.resolved_method_type();
385 const bool has_appendix = appendix.not_null();
386 const bool has_method_type = method_type.not_null();
387
388 // Write the flags.
389 set_method_flags(as_TosState(adapter->result_type()),
390 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
391 ((has_method_type ? 1 : 0) << has_method_type_shift) |
392 ( 1 << is_final_shift ),
393 adapter->size_of_parameters());
394
395 if (TraceInvokeDynamic) {
396 ttyLocker ttyl;
397 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ",
398 invoke_code,
399 p2i(appendix()), (has_appendix ? "" : " (unused)"),
400 p2i(method_type()), (has_method_type ? "" : " (unused)"),
401 p2i(adapter()));
402 adapter->print();
403 if (has_appendix) appendix()->print();
404 }
405
406 // Method handle invokes and invokedynamic sites use both cp cache words.
407 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
408 // In the general case, this could be the call site's MethodType,
409 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
410 // f1 contains the adapter method which manages the actual call.
411 // In the general case, this is a compiled LambdaForm.
412 // (The Java code is free to optimize these calls by binding other
413 // sorts of methods and appendices to call sites.)
414 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
415 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
416 // Even with the appendix, the method will never take more than 255 parameter slots.
417 //
418 // This means that given a call site like (List)mh.invoke("foo"),
419 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
420 // not '(Ljava/lang/String;)Ljava/util/List;'.
421 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
422 // This allows us to create fewer Methods, while keeping type safety.
423 //
424
425 // Store appendix, if any.
426 if (has_appendix) {
427 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
428 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
429 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
430 resolved_references->obj_at_put(appendix_index, appendix());
431 }
432
433 // Store MethodType, if any.
434 if (has_method_type) {
435 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
436 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
437 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
438 resolved_references->obj_at_put(method_type_index, method_type());
439 }
440
441 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
442
443 // The interpreter assembly code does not check byte_2,
444 // but it is used by is_resolved, method_if_resolved, etc.
445 set_bytecode_1(invoke_code);
446 NOT_PRODUCT(verify(tty));
447 if (TraceInvokeDynamic) {
448 ttyLocker ttyl;
449 this->print(tty, 0);
450 }
451 }
452
453 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
454 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
455
456 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
457 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
458 "No LinkageError exception");
459
460 // Use the resolved_references() lock for this cpCache entry.
461 // resolved_references are created for all classes with Invokedynamic, MethodHandle
462 // or MethodType constant pool cache entries.
463 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
464 assert(resolved_references() != NULL,
465 "a resolved_references array should have been created for this class");
466 ObjectLocker ol(resolved_references, THREAD);
467
468 // if f1 is not null or the indy_resolution_failed flag is set then another
469 // thread either succeeded in resolving the method or got a LinkageError
470 // exception, before this thread was able to record its failure. So, clear
471 // this thread's exception and return false so caller can use the earlier
472 // thread's result.
473 if (!is_f1_null() || indy_resolution_failed()) {
474 CLEAR_PENDING_EXCEPTION;
475 return false;
476 }
477
478 Symbol* error = PENDING_EXCEPTION->klass()->name();
479 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
480
481 SystemDictionary::add_resolution_error(cpool, index, error, message);
482 set_indy_resolution_failed();
483 return true;
484 }
485
486 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
487 // Decode the action of set_method and set_interface_call
488 Bytecodes::Code invoke_code = bytecode_1();
489 if (invoke_code != (Bytecodes::Code)0) {
490 Metadata* f1 = f1_ord();
491 if (f1 != NULL) {
492 switch (invoke_code) {
493 case Bytecodes::_invokeinterface:
494 assert(f1->is_klass(), "");
495 return klassItable::method_for_itable_index((InstanceKlass*)f1, f2_as_index());
496 case Bytecodes::_invokestatic:
497 case Bytecodes::_invokespecial:
498 assert(!has_appendix(), "");
499 case Bytecodes::_invokehandle:
500 case Bytecodes::_invokedynamic:
501 assert(f1->is_method(), "");
502 return (Method*)f1;
503 default:
504 break;
505 }
506 }
507 }
508 invoke_code = bytecode_2();
509 if (invoke_code != (Bytecodes::Code)0) {
510 switch (invoke_code) {
511 case Bytecodes::_invokevirtual:
512 if (is_vfinal()) {
513 // invokevirtual
514 Method* m = f2_as_vfinal_method();
515 assert(m->is_method(), "");
516 return m;
517 } else {
518 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
519 if (cpool->tag_at(holder_index).is_klass()) {
520 Klass* klass = cpool->resolved_klass_at(holder_index);
521 return klass->method_at_vtable(f2_as_index());
522 }
523 }
524 break;
525 default:
526 break;
527 }
528 }
529 return NULL;
530 }
531
532
533 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
534 if (!has_appendix())
535 return NULL;
536 const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset;
537 objArrayOop resolved_references = cpool->resolved_references();
538 return resolved_references->obj_at(ref_index);
539 }
540
541
542 oop ConstantPoolCacheEntry::method_type_if_resolved(const constantPoolHandle& cpool) {
543 if (!has_method_type())
544 return NULL;
545 const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset;
546 objArrayOop resolved_references = cpool->resolved_references();
547 return resolved_references->obj_at(ref_index);
548 }
549
550
551 #if INCLUDE_JVMTI
552
553 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
554 if (log_is_enabled(Info, redefine, class, update)) {
555 ResourceMark rm;
556 if (!(*trace_name_printed)) {
557 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
558 *trace_name_printed = true;
559 }
560 log_debug(redefine, class, update, constantpool)
561 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string());
562 }
563 }
564
565 // RedefineClasses() API support:
566 // If this ConstantPoolCacheEntry refers to old_method then update it
567 // to refer to new_method.
568 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
569 Method* new_method, bool * trace_name_printed) {
570
571 if (is_vfinal()) {
572 // virtual and final so _f2 contains method ptr instead of vtable index
573 if (f2_as_vfinal_method() == old_method) {
574 // match old_method so need an update
575 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
576 _f2 = (intptr_t)new_method;
577 log_adjust("vfinal", old_method, new_method, trace_name_printed);
578 }
579 return;
580 }
581
582 assert (_f1 != NULL, "should not call with uninteresting entry");
583
584 if (!(_f1->is_method())) {
585 // _f1 is a Klass* for an interface, _f2 is the method
586 if (f2_as_interface_method() == old_method) {
587 _f2 = (intptr_t)new_method;
588 log_adjust("interface", old_method, new_method, trace_name_printed);
589 }
590 } else if (_f1 == old_method) {
591 _f1 = new_method;
592 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
593 }
594 }
595
596 // a constant pool cache entry should never contain old or obsolete methods
597 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
598 Method* m = get_interesting_method_entry(NULL);
599 // return false if m refers to a non-deleted old or obsolete method
600 if (m != NULL) {
601 assert(m->is_valid() && m->is_method(), "m is a valid method");
602 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
603 } else {
604 return true;
605 }
606 }
607
608 Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) {
609 if (!is_method_entry()) {
610 // not a method entry so not interesting by default
611 return NULL;
612 }
613 Method* m = NULL;
614 if (is_vfinal()) {
615 // virtual and final so _f2 contains method ptr instead of vtable index
616 m = f2_as_vfinal_method();
617 } else if (is_f1_null()) {
618 // NULL _f1 means this is a virtual entry so also not interesting
619 return NULL;
620 } else {
621 if (!(_f1->is_method())) {
622 // _f1 is a Klass* for an interface
623 m = f2_as_interface_method();
624 } else {
625 m = f1_as_method();
626 }
627 }
628 assert(m != NULL && m->is_method(), "sanity check");
629 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
630 // robustness for above sanity checks or method is not in
631 // the interesting class
632 return NULL;
633 }
634 // the method is in the interesting class so the entry is interesting
635 return m;
636 }
637 #endif // INCLUDE_JVMTI
638
639 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
640 // print separator
641 if (index == 0) st->print_cr(" -------------");
642 // print entry
643 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
644 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
645 constant_pool_index());
646 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
647 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
648 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
649 st->print_cr(" -------------");
650 }
651
652 void ConstantPoolCacheEntry::verify(outputStream* st) const {
653 // not implemented yet
654 }
655
656 // Implementation of ConstantPoolCache
657
658 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
659 const intStack& index_map,
660 const intStack& invokedynamic_index_map,
661 const intStack& invokedynamic_map, TRAPS) {
662
663 const int length = index_map.length() + invokedynamic_index_map.length();
664 int size = ConstantPoolCache::size(length);
665
666 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
667 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
668 }
669
670 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
671 const intArray& invokedynamic_inverse_index_map,
672 const intArray& invokedynamic_references_map) {
673 for (int i = 0; i < inverse_index_map.length(); i++) {
674 ConstantPoolCacheEntry* e = entry_at(i);
675 int original_index = inverse_index_map.at(i);
676 e->initialize_entry(original_index);
677 assert(entry_at(i) == e, "sanity");
678 }
679
680 // Append invokedynamic entries at the end
681 int invokedynamic_offset = inverse_index_map.length();
682 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
683 int offset = i + invokedynamic_offset;
684 ConstantPoolCacheEntry* e = entry_at(offset);
685 int original_index = invokedynamic_inverse_index_map.at(i);
686 e->initialize_entry(original_index);
687 assert(entry_at(offset) == e, "sanity");
688 }
689
690 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
691 const int cpci = invokedynamic_references_map.at(ref);
692 if (cpci >= 0) {
693 #ifdef ASSERT
694 // invokedynamic and invokehandle have more entries; check if they
695 // all point to the same constant pool cache entry.
696 for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
697 const int cpci_next = invokedynamic_references_map.at(ref + entry);
698 assert(cpci == cpci_next, "%d == %d", cpci, cpci_next);
699 }
700 #endif
701 entry_at(cpci)->initialize_resolved_reference_index(ref);
702 ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries
703 }
704 }
705 }
706
707 void ConstantPoolCache::verify_just_initialized() {
708 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
709 }
710
711 void ConstantPoolCache::remove_unshareable_info() {
712 walk_entries_for_initialization(/*check_only = */ false);
713 }
714
715 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
716 assert(DumpSharedSpaces, "sanity");
717 // When dumping the archive, we want to clean up the ConstantPoolCache
718 // to remove any effect of linking due to the execution of Java code --
719 // each ConstantPoolCacheEntry will have the same contents as if
720 // ConstantPoolCache::initialize has just returned:
721 //
722 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
723 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
724 // - All other bits in the entries are cleared to zero.
725 ResourceMark rm;
726
727 InstanceKlass* ik = constant_pool()->pool_holder();
728 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
729 memset(f2_used, 0, sizeof(bool) * length());
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(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(NULL);
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 (CompressedOops::is_null(_archived_references)) {
778 return NULL;
779 }
780 return MetaspaceShared::materialize_archived_object(CompressedOops::decode_not_null(_archived_references));
781 }
782
783 void ConstantPoolCache::set_archived_references(oop o) {
784 assert(DumpSharedSpaces, "called only during runtime");
785 _archived_references = CompressedOops::encode(o);
786 }
787 #endif
788
789 #if INCLUDE_JVMTI
790 // RedefineClasses() API support:
791 // If any entry of this ConstantPoolCache points to any of
792 // old_methods, replace it with the corresponding new_method.
793 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
794 for (int i = 0; i < length(); i++) {
795 ConstantPoolCacheEntry* entry = entry_at(i);
796 Method* old_method = entry->get_interesting_method_entry(holder);
797 if (old_method == NULL || !old_method->is_old()) {
798 continue; // skip uninteresting entries
799 }
800 if (old_method->is_deleted()) {
801 // clean up entries with deleted methods
802 entry->initialize_entry(entry->constant_pool_index());
803 continue;
804 }
805 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
806
807 assert(new_method != NULL, "method_with_idnum() should not be NULL");
808 assert(old_method != new_method, "sanity check");
809
810 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
811 }
812 }
813
814 // the constant pool cache should never contain old or obsolete methods
815 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
816 for (int i = 1; i < length(); i++) {
817 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
818 !entry_at(i)->check_no_old_or_obsolete_entries()) {
819 return false;
820 }
821 }
822 return true;
823 }
824
825 void ConstantPoolCache::dump_cache() {
826 for (int i = 1; i < length(); i++) {
827 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
828 entry_at(i)->print(tty, i);
829 }
830 }
831 }
832 #endif // INCLUDE_JVMTI
833
834 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
835 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
836 it->push(&_constant_pool);
837 it->push(&_reference_map);
838 }
839
840 // Printing
841
842 void ConstantPoolCache::print_on(outputStream* st) const {
843 assert(is_constantPoolCache(), "obj must be constant pool cache");
844 st->print_cr("%s", internal_name());
845 // print constant pool cache entries
846 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
847 }
848
849 void ConstantPoolCache::print_value_on(outputStream* st) const {
850 assert(is_constantPoolCache(), "obj must be constant pool cache");
851 st->print("cache [%d]", length());
852 print_address_on(st);
853 st->print(" for ");
854 constant_pool()->print_value_on(st);
855 }
856
857
858 // Verification
859
860 void ConstantPoolCache::verify_on(outputStream* st) {
861 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
862 // print constant pool cache entries
863 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
864 }