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/resourceArea.hpp"
36 #include "memory/universe.hpp"
37 #include "oops/access.inline.hpp"
38 #include "oops/constantPool.inline.hpp"
39 #include "oops/cpCache.inline.hpp"
40 #include "oops/objArrayOop.inline.hpp"
41 #include "oops/oop.inline.hpp"
42 #include "prims/methodHandles.hpp"
43 #include "runtime/atomic.hpp"
44 #include "runtime/handles.inline.hpp"
45 #include "runtime/orderAccess.inline.hpp"
46 #include "utilities/macros.hpp"
47
48 // Implementation of ConstantPoolCacheEntry
49
50 void ConstantPoolCacheEntry::initialize_entry(int index) {
51 assert(0 < index && index < 0x10000, "sanity check");
52 _indices = index;
53 _f1 = NULL;
54 _f2 = _flags = 0;
55 assert(constant_pool_index() == index, "");
56 }
57
58 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) {
59 assert((_indices & (~cp_index_mask)) == 0, "sanity");
60 assert(_f1 == NULL, "sanity");
61 assert(_flags == 0, "sanity");
62 if (!f2_used) {
63 assert(_f2 == 0, "sanity");
64 }
65 }
66
67 void ConstantPoolCacheEntry::reinitialize(bool f2_used) {
68 _indices &= cp_index_mask;
69 _f1 = NULL;
70 _flags = 0;
71 if (!f2_used) {
72 _f2 = 0;
73 }
74 }
75
76 int ConstantPoolCacheEntry::make_flags(TosState state,
77 int option_bits,
78 int field_index_or_method_params) {
79 assert(state < number_of_states, "Invalid state in make_flags");
80 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
81 // Preserve existing flag bit values
82 // The low bits are a field offset, or else the method parameter size.
83 #ifdef ASSERT
84 TosState old_state = flag_state();
85 assert(old_state == (TosState)0 || old_state == state,
86 "inconsistent cpCache flags state");
87 #endif
88 return (_flags | f) ;
89 }
90
91 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
92 #ifdef ASSERT
93 // Read once.
94 volatile Bytecodes::Code c = bytecode_1();
95 assert(c == 0 || c == code || code == 0, "update must be consistent");
96 #endif
97 // Need to flush pending stores here before bytecode is written.
98 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift));
99 }
100
101 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
102 #ifdef ASSERT
103 // Read once.
104 volatile Bytecodes::Code c = bytecode_2();
105 assert(c == 0 || c == code || code == 0, "update must be consistent");
106 #endif
107 // Need to flush pending stores here before bytecode is written.
108 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift));
109 }
110
111 // Sets f1, ordering with previous writes.
112 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
113 assert(f1 != NULL, "");
114 OrderAccess::release_store(&_f1, f1);
115 }
116
117 void ConstantPoolCacheEntry::set_indy_resolution_failed() {
118 OrderAccess::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift));
119 }
120
121 // Note that concurrent update of both bytecodes can leave one of them
122 // reset to zero. This is harmless; the interpreter will simply re-resolve
123 // the damaged entry. More seriously, the memory synchronization is needed
124 // to flush other fields (f1, f2) completely to memory before the bytecodes
125 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
126 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
127 Bytecodes::Code put_code,
128 Klass* field_holder,
129 int field_index,
130 int field_offset,
131 TosState field_type,
132 bool is_final,
133 bool is_volatile,
134 Klass* root_klass) {
135 set_f1(field_holder);
136 set_f2(field_offset);
137 assert((field_index & field_index_mask) == field_index,
138 "field index does not fit in low flag bits");
139 set_field_flags(field_type,
140 ((is_volatile ? 1 : 0) << is_volatile_shift) |
141 ((is_final ? 1 : 0) << is_final_shift),
142 field_index);
143 set_bytecode_1(get_code);
144 set_bytecode_2(put_code);
145 NOT_PRODUCT(verify(tty));
146 }
147
148 void ConstantPoolCacheEntry::set_parameter_size(int value) {
149 // This routine is called only in corner cases where the CPCE is not yet initialized.
150 // See AbstractInterpreter::deopt_continue_after_entry.
151 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
152 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
153 // Setting the parameter size by itself is only safe if the
154 // current value of _flags is 0, otherwise another thread may have
155 // updated it and we don't want to overwrite that value. Don't
156 // bother trying to update it once it's nonzero but always make
157 // sure that the final parameter size agrees with what was passed.
158 if (_flags == 0) {
159 intx newflags = (value & parameter_size_mask);
160 Atomic::cmpxchg(newflags, &_flags, (intx)0);
161 }
162 guarantee(parameter_size() == value,
163 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
164 }
165
166 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
167 const methodHandle& method,
168 int vtable_index,
169 bool sender_is_interface) {
170 bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean
171 assert(method->interpreter_entry() != NULL, "should have been set at this point");
172 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
173
174 int byte_no = -1;
175 bool change_to_virtual = false;
176 InstanceKlass* holder = NULL; // have to declare this outside the switch
177 switch (invoke_code) {
178 case Bytecodes::_invokeinterface:
179 holder = method->method_holder();
180 // check for private interface method invocations
181 if (vtable_index == Method::nonvirtual_vtable_index && holder->is_interface() ) {
182 assert(method->is_private(), "unexpected non-private method");
183 assert(method->can_be_statically_bound(), "unexpected non-statically-bound method");
184 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
185 set_method_flags(as_TosState(method->result_type()),
186 ( 1 << is_vfinal_shift) |
187 ((method->is_final_method() ? 1 : 0) << is_final_shift),
188 method()->size_of_parameters());
189 set_f2_as_vfinal_method(method());
190 byte_no = 2;
191 set_f1(holder); // interface klass*
192 break;
193 }
194 else {
195 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
196 // instruction links to a non-interface method (in Object). This can happen when
197 // an interface redeclares an Object method (like CharSequence declaring toString())
198 // or when invokeinterface is used explicitly.
199 // In that case, the method has no itable index and must be invoked as a virtual.
200 // Set a flag to keep track of this corner case.
201 assert(holder->is_interface() || holder == SystemDictionary::Object_klass(), "unexpected holder class");
202 assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
203 change_to_virtual = true;
204
205 // ...and fall through as if we were handling invokevirtual:
206 }
207 case Bytecodes::_invokevirtual:
208 {
209 if (!is_vtable_call) {
210 assert(method->can_be_statically_bound(), "");
211 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
212 set_method_flags(as_TosState(method->result_type()),
213 ( 1 << is_vfinal_shift) |
214 ((method->is_final_method() ? 1 : 0) << is_final_shift) |
215 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
216 method()->size_of_parameters());
217 set_f2_as_vfinal_method(method());
218 } else {
219 assert(!method->can_be_statically_bound(), "");
220 assert(vtable_index >= 0, "valid index");
221 assert(!method->is_final_method(), "sanity");
222 set_method_flags(as_TosState(method->result_type()),
223 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
224 method()->size_of_parameters());
225 set_f2(vtable_index);
226 }
227 byte_no = 2;
228 break;
229 }
230
231 case Bytecodes::_invokespecial:
232 case Bytecodes::_invokestatic:
233 assert(!is_vtable_call, "");
234 // Note: Read and preserve the value of the is_vfinal flag on any
235 // invokevirtual bytecode shared with this constant pool cache entry.
236 // It is cheap and safe to consult is_vfinal() at all times.
237 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
238 set_method_flags(as_TosState(method->result_type()),
239 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
240 ((method->is_final_method() ? 1 : 0) << is_final_shift),
241 method()->size_of_parameters());
242 set_f1(method());
243 byte_no = 1;
244 break;
245 default:
246 ShouldNotReachHere();
247 break;
248 }
249
250 // Note: byte_no also appears in TemplateTable::resolve.
251 if (byte_no == 1) {
252 assert(invoke_code != Bytecodes::_invokevirtual &&
253 invoke_code != Bytecodes::_invokeinterface, "");
254 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
255 // has to be checked that it is a subclass of the current class every time this bytecode
256 // is executed.
257 if (invoke_code != Bytecodes::_invokespecial || !sender_is_interface ||
258 method->name() == vmSymbols::object_initializer_name()) {
259 set_bytecode_1(invoke_code);
260 }
261 } else if (byte_no == 2) {
262 if (change_to_virtual) {
263 assert(invoke_code == Bytecodes::_invokeinterface, "");
264 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
265 //
266 // Workaround for the case where we encounter an invokeinterface, but we
267 // should really have an _invokevirtual since the resolved method is a
268 // virtual method in java.lang.Object. This is a corner case in the spec
269 // but is presumably legal. javac does not generate this code.
270 //
271 // We do not set bytecode_1() to _invokeinterface, because that is the
272 // bytecode # used by the interpreter to see if it is resolved. In this
273 // case, the method gets reresolved with caller for each interface call
274 // because the actual selected method may not be public.
275 //
276 // We set bytecode_2() to _invokevirtual.
277 // See also interpreterRuntime.cpp. (8/25/2000)
278 } else {
279 assert(invoke_code == Bytecodes::_invokevirtual ||
280 (invoke_code == Bytecodes::_invokeinterface &&
281 ((method->is_private() ||
282 (method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))),
283 "unexpected invocation mode");
284 if (invoke_code == Bytecodes::_invokeinterface &&
285 (method->is_private() || method->is_final())) {
286 // We set bytecode_1() to _invokeinterface, because that is the
287 // bytecode # used by the interpreter to see if it is resolved.
288 // We set bytecode_2() to _invokevirtual.
289 set_bytecode_1(invoke_code);
290 }
291 }
292 // set up for invokevirtual, even if linking for invokeinterface also:
293 set_bytecode_2(Bytecodes::_invokevirtual);
294 } else {
295 ShouldNotReachHere();
296 }
297 NOT_PRODUCT(verify(tty));
298 }
299
300 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
301 bool sender_is_interface) {
302 int index = Method::nonvirtual_vtable_index;
303 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
304 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
305 }
306
307 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
308 // either the method is a miranda or its holder should accept the given index
309 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
310 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
311 set_direct_or_vtable_call(invoke_code, method, index, false);
312 }
313
314 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
315 Klass* referenced_klass,
316 const methodHandle& method, int index) {
317 assert(method->method_holder()->verify_itable_index(index), "");
318 assert(invoke_code == Bytecodes::_invokeinterface, "");
319 InstanceKlass* interf = method->method_holder();
320 assert(interf->is_interface(), "must be an interface");
321 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
322 set_f1(referenced_klass);
323 set_f2((intx)method());
324 set_method_flags(as_TosState(method->result_type()),
325 0, // no option bits
326 method()->size_of_parameters());
327 set_bytecode_1(Bytecodes::_invokeinterface);
328 }
329
330
331 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
332 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
333 }
334
335 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
336 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
337 }
338
339 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
340 Bytecodes::Code invoke_code,
341 const CallInfo &call_info) {
342 // NOTE: This CPCE can be the subject of data races.
343 // There are three words to update: flags, refs[f2], f1 (in that order).
344 // Writers must store all other values before f1.
345 // Readers must test f1 first for non-null before reading other fields.
346 // Competing writers must acquire exclusive access via a lock.
347 // A losing writer waits on the lock until the winner writes f1 and leaves
348 // the lock, so that when the losing writer returns, he can use the linked
349 // cache entry.
350
351 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
352 // Use the resolved_references() lock for this cpCache entry.
353 // resolved_references are created for all classes with Invokedynamic, MethodHandle
354 // or MethodType constant pool cache entries.
355 assert(resolved_references() != NULL,
356 "a resolved_references array should have been created for this class");
357 ObjectLocker ol(resolved_references, Thread::current());
358 if (!is_f1_null()) {
359 return;
360 }
361
362 if (indy_resolution_failed()) {
363 // Before we got here, another thread got a LinkageError exception during
364 // resolution. Ignore our success and throw their exception.
365 ConstantPoolCache* cpCache = cpool->cache();
366 int index = -1;
367 for (int i = 0; i < cpCache->length(); i++) {
368 if (cpCache->entry_at(i) == this) {
369 index = i;
370 break;
371 }
372 }
373 guarantee(index >= 0, "Didn't find cpCache entry!");
374 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
375 ConstantPool::encode_invokedynamic_index(index));
376 Thread* THREAD = Thread::current();
377 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
378 return;
379 }
380
381 const methodHandle adapter = call_info.resolved_method();
382 const Handle appendix = call_info.resolved_appendix();
383 const Handle method_type = call_info.resolved_method_type();
384 const bool has_appendix = appendix.not_null();
385 const bool has_method_type = method_type.not_null();
386
387 // Write the flags.
388 set_method_flags(as_TosState(adapter->result_type()),
389 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
390 ((has_method_type ? 1 : 0) << has_method_type_shift) |
391 ( 1 << is_final_shift ),
392 adapter->size_of_parameters());
393
394 if (TraceInvokeDynamic) {
395 ttyLocker ttyl;
396 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ",
397 invoke_code,
398 p2i(appendix()), (has_appendix ? "" : " (unused)"),
399 p2i(method_type()), (has_method_type ? "" : " (unused)"),
400 p2i(adapter()));
401 adapter->print();
402 if (has_appendix) appendix()->print();
403 }
404
405 // Method handle invokes and invokedynamic sites use both cp cache words.
406 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
407 // In the general case, this could be the call site's MethodType,
408 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
409 // f1 contains the adapter method which manages the actual call.
410 // In the general case, this is a compiled LambdaForm.
411 // (The Java code is free to optimize these calls by binding other
412 // sorts of methods and appendices to call sites.)
413 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
414 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
415 // Even with the appendix, the method will never take more than 255 parameter slots.
416 //
417 // This means that given a call site like (List)mh.invoke("foo"),
418 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
419 // not '(Ljava/lang/String;)Ljava/util/List;'.
420 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
421 // This allows us to create fewer Methods, while keeping type safety.
422 //
423
424 // Store appendix, if any.
425 if (has_appendix) {
426 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
427 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
428 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
429 resolved_references->obj_at_put(appendix_index, appendix());
430 }
431
432 // Store MethodType, if any.
433 if (has_method_type) {
434 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
435 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
436 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
437 resolved_references->obj_at_put(method_type_index, method_type());
438 }
439
440 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
441
442 // The interpreter assembly code does not check byte_2,
443 // but it is used by is_resolved, method_if_resolved, etc.
444 set_bytecode_1(invoke_code);
445 NOT_PRODUCT(verify(tty));
446 if (TraceInvokeDynamic) {
447 ttyLocker ttyl;
448 this->print(tty, 0);
449 }
450 }
451
452 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
453 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
454
455 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
456 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
457 "No LinkageError exception");
458
459 // Use the resolved_references() lock for this cpCache entry.
460 // resolved_references are created for all classes with Invokedynamic, MethodHandle
461 // or MethodType constant pool cache entries.
462 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
463 assert(resolved_references() != NULL,
464 "a resolved_references array should have been created for this class");
465 ObjectLocker ol(resolved_references, THREAD);
466
467 // if f1 is not null or the indy_resolution_failed flag is set then another
468 // thread either succeeded in resolving the method or got a LinkageError
469 // exception, before this thread was able to record its failure. So, clear
470 // this thread's exception and return false so caller can use the earlier
471 // thread's result.
472 if (!is_f1_null() || indy_resolution_failed()) {
473 CLEAR_PENDING_EXCEPTION;
474 return false;
475 }
476
477 Symbol* error = PENDING_EXCEPTION->klass()->name();
478 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
479 assert(message != NULL, "Missing detail message");
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((Klass*)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 // Loading an archive root forces the oop to become strongly reachable.
778 // For example, if it is loaded during concurrent marking in a SATB
779 // collector, it will be enqueued to the SATB queue, effectively
780 // shading the previously white object gray.
781 return RootAccess<IN_ARCHIVE_ROOT>::oop_load(&_archived_references);
782 }
783
784 void ConstantPoolCache::set_archived_references(oop o) {
785 assert(DumpSharedSpaces, "called only during runtime");
786 RootAccess<IN_ARCHIVE_ROOT>::oop_store(&_archived_references, o);
787 }
788 #endif
789
790 #if INCLUDE_JVMTI
791 // RedefineClasses() API support:
792 // If any entry of this ConstantPoolCache points to any of
793 // old_methods, replace it with the corresponding new_method.
794 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
795 for (int i = 0; i < length(); i++) {
796 ConstantPoolCacheEntry* entry = entry_at(i);
797 Method* old_method = entry->get_interesting_method_entry(holder);
798 if (old_method == NULL || !old_method->is_old()) {
799 continue; // skip uninteresting entries
800 }
801 if (old_method->is_deleted()) {
802 // clean up entries with deleted methods
803 entry->initialize_entry(entry->constant_pool_index());
804 continue;
805 }
806 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
807
808 assert(new_method != NULL, "method_with_idnum() should not be NULL");
809 assert(old_method != new_method, "sanity check");
810
811 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
812 }
813 }
814
815 // the constant pool cache should never contain old or obsolete methods
816 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
817 for (int i = 1; i < length(); i++) {
818 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
819 !entry_at(i)->check_no_old_or_obsolete_entries()) {
820 return false;
821 }
822 }
823 return true;
824 }
825
826 void ConstantPoolCache::dump_cache() {
827 for (int i = 1; i < length(); i++) {
828 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
829 entry_at(i)->print(tty, i);
830 }
831 }
832 }
833 #endif // INCLUDE_JVMTI
834
835 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
836 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
837 it->push(&_constant_pool);
838 it->push(&_reference_map);
839 }
840
841 // Printing
842
843 void ConstantPoolCache::print_on(outputStream* st) const {
844 assert(is_constantPoolCache(), "obj must be constant pool cache");
845 st->print_cr("%s", internal_name());
846 // print constant pool cache entries
847 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
848 }
849
850 void ConstantPoolCache::print_value_on(outputStream* st) const {
851 assert(is_constantPoolCache(), "obj must be constant pool cache");
852 st->print("cache [%d]", length());
853 print_address_on(st);
854 st->print(" for ");
855 constant_pool()->print_value_on(st);
856 }
857
858
859 // Verification
860
861 void ConstantPoolCache::verify_on(outputStream* st) {
862 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
863 // print constant pool cache entries
864 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
865 }