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 bool has_appendix = appendix.not_null();
385 const bool has_local_sig = call_info.has_local_signature();
386 assert(has_local_sig, "MHs and indy are always sig-poly");
387
388 // Write the flags.
389 set_method_flags(as_TosState(adapter->result_type()),
390 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
391 ((has_local_sig ? 1 : 0) << has_local_signature_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=" PTR_FORMAT "%s ",
398 invoke_code,
399 p2i(appendix()), (has_appendix ? "" : " (unused)"),
400 p2i(adapter()), (has_local_sig ? " (local signature)" : ""));
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();
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 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
433
434 // The interpreter assembly code does not check byte_2,
435 // but it is used by is_resolved, method_if_resolved, etc.
436 set_bytecode_1(invoke_code);
437 NOT_PRODUCT(verify(tty));
438 if (TraceInvokeDynamic) {
439 ttyLocker ttyl;
440 this->print(tty, 0);
441 }
442
443 assert(has_appendix == this->has_appendix(), "proper storage of appendix flag");
444 assert(has_local_sig == this->has_local_signature(), "proper storage of signature flag");
445 }
446
447 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
448 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
449
450 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
451 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
452 "No LinkageError exception");
453
454 // Use the resolved_references() lock for this cpCache entry.
455 // resolved_references are created for all classes with Invokedynamic, MethodHandle
456 // or MethodType constant pool cache entries.
457 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
458 assert(resolved_references() != NULL,
459 "a resolved_references array should have been created for this class");
460 ObjectLocker ol(resolved_references, THREAD);
461
462 // if f1 is not null or the indy_resolution_failed flag is set then another
463 // thread either succeeded in resolving the method or got a LinkageError
464 // exception, before this thread was able to record its failure. So, clear
465 // this thread's exception and return false so caller can use the earlier
466 // thread's result.
467 if (!is_f1_null() || indy_resolution_failed()) {
468 CLEAR_PENDING_EXCEPTION;
469 return false;
470 }
471
472 Symbol* error = PENDING_EXCEPTION->klass()->name();
473 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
474
475 SystemDictionary::add_resolution_error(cpool, index, error, message);
476 set_indy_resolution_failed();
477 return true;
478 }
479
480 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
481 // Decode the action of set_method and set_interface_call
482 Bytecodes::Code invoke_code = bytecode_1();
483 if (invoke_code != (Bytecodes::Code)0) {
484 Metadata* f1 = f1_ord();
485 if (f1 != NULL) {
486 switch (invoke_code) {
487 case Bytecodes::_invokeinterface:
488 assert(f1->is_klass(), "");
489 return klassItable::method_for_itable_index((InstanceKlass*)f1, f2_as_index());
490 case Bytecodes::_invokestatic:
491 case Bytecodes::_invokespecial:
492 assert(!has_appendix(), "");
493 case Bytecodes::_invokehandle:
494 case Bytecodes::_invokedynamic:
495 assert(f1->is_method(), "");
496 return (Method*)f1;
497 default:
498 break;
499 }
500 }
501 }
502 invoke_code = bytecode_2();
503 if (invoke_code != (Bytecodes::Code)0) {
504 switch (invoke_code) {
505 case Bytecodes::_invokevirtual:
506 if (is_vfinal()) {
507 // invokevirtual
508 Method* m = f2_as_vfinal_method();
509 assert(m->is_method(), "");
510 return m;
511 } else {
512 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
513 if (cpool->tag_at(holder_index).is_klass()) {
514 Klass* klass = cpool->resolved_klass_at(holder_index);
515 return klass->method_at_vtable(f2_as_index());
516 }
517 }
518 break;
519 default:
520 break;
521 }
522 }
523 return NULL;
524 }
525
526
527 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
528 if (!has_appendix())
529 return NULL;
530 const int ref_index = f2_as_index();
531 objArrayOop resolved_references = cpool->resolved_references();
532 return resolved_references->obj_at(ref_index);
533 }
534
535
536 #if INCLUDE_JVMTI
537
538 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
539 if (log_is_enabled(Info, redefine, class, update)) {
540 ResourceMark rm;
541 if (!(*trace_name_printed)) {
542 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
543 *trace_name_printed = true;
544 }
545 log_debug(redefine, class, update, constantpool)
546 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string());
547 }
548 }
549
550 // RedefineClasses() API support:
551 // If this ConstantPoolCacheEntry refers to old_method then update it
552 // to refer to new_method.
553 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
554 Method* new_method, bool * trace_name_printed) {
555
556 if (is_vfinal()) {
557 // virtual and final so _f2 contains method ptr instead of vtable index
558 if (f2_as_vfinal_method() == old_method) {
559 // match old_method so need an update
560 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
561 _f2 = (intptr_t)new_method;
562 log_adjust("vfinal", old_method, new_method, trace_name_printed);
563 }
564 return;
565 }
566
567 assert (_f1 != NULL, "should not call with uninteresting entry");
568
569 if (!(_f1->is_method())) {
570 // _f1 is a Klass* for an interface, _f2 is the method
571 if (f2_as_interface_method() == old_method) {
572 _f2 = (intptr_t)new_method;
573 log_adjust("interface", old_method, new_method, trace_name_printed);
574 }
575 } else if (_f1 == old_method) {
576 _f1 = new_method;
577 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
578 }
579 }
580
581 // a constant pool cache entry should never contain old or obsolete methods
582 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
583 Method* m = get_interesting_method_entry(NULL);
584 // return false if m refers to a non-deleted old or obsolete method
585 if (m != NULL) {
586 assert(m->is_valid() && m->is_method(), "m is a valid method");
587 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
588 } else {
589 return true;
590 }
591 }
592
593 Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) {
594 if (!is_method_entry()) {
595 // not a method entry so not interesting by default
596 return NULL;
597 }
598 Method* m = NULL;
599 if (is_vfinal()) {
600 // virtual and final so _f2 contains method ptr instead of vtable index
601 m = f2_as_vfinal_method();
602 } else if (is_f1_null()) {
603 // NULL _f1 means this is a virtual entry so also not interesting
604 return NULL;
605 } else {
606 if (!(_f1->is_method())) {
607 // _f1 is a Klass* for an interface
608 m = f2_as_interface_method();
609 } else {
610 m = f1_as_method();
611 }
612 }
613 assert(m != NULL && m->is_method(), "sanity check");
614 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
615 // robustness for above sanity checks or method is not in
616 // the interesting class
617 return NULL;
618 }
619 // the method is in the interesting class so the entry is interesting
620 return m;
621 }
622 #endif // INCLUDE_JVMTI
623
624 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
625 // print separator
626 if (index == 0) st->print_cr(" -------------");
627 // print entry
628 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
629 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
630 constant_pool_index());
631 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
632 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
633 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
634 st->print_cr(" -------------");
635 }
636
637 void ConstantPoolCacheEntry::verify(outputStream* st) const {
638 // not implemented yet
639 }
640
641 // Implementation of ConstantPoolCache
642
643 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
644 const intStack& index_map,
645 const intStack& invokedynamic_index_map,
646 const intStack& invokedynamic_map, TRAPS) {
647
648 const int length = index_map.length() + invokedynamic_index_map.length();
649 int size = ConstantPoolCache::size(length);
650
651 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
652 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
653 }
654
655 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
656 const intArray& invokedynamic_inverse_index_map,
657 const intArray& appendix_references_map) {
658 for (int i = 0; i < inverse_index_map.length(); i++) {
659 ConstantPoolCacheEntry* e = entry_at(i);
660 int original_index = inverse_index_map.at(i);
661 e->initialize_entry(original_index);
662 assert(entry_at(i) == e, "sanity");
663 }
664
665 // Append invokedynamic entries at the end
666 int invokedynamic_offset = inverse_index_map.length();
667 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
668 int offset = i + invokedynamic_offset;
669 ConstantPoolCacheEntry* e = entry_at(offset);
670 int original_index = invokedynamic_inverse_index_map.at(i);
671 e->initialize_entry(original_index);
672 assert(entry_at(offset) == e, "sanity");
673 }
674
675 for (int ref = 0; ref < appendix_references_map.length(); ref++) {
676 const int cpci = appendix_references_map.at(ref);
677 if (cpci >= 0) {
678 entry_at(cpci)->initialize_resolved_reference_index(ref);
679 }
680 }
681 }
682
683 void ConstantPoolCache::verify_just_initialized() {
684 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
685 }
686
687 void ConstantPoolCache::remove_unshareable_info() {
688 walk_entries_for_initialization(/*check_only = */ false);
689 }
690
691 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
692 assert(DumpSharedSpaces, "sanity");
693 // When dumping the archive, we want to clean up the ConstantPoolCache
694 // to remove any effect of linking due to the execution of Java code --
695 // each ConstantPoolCacheEntry will have the same contents as if
696 // ConstantPoolCache::initialize has just returned:
697 //
698 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
699 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
700 // - All other bits in the entries are cleared to zero.
701 ResourceMark rm;
702
703 InstanceKlass* ik = constant_pool()->pool_holder();
704 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
705 memset(f2_used, 0, sizeof(bool) * length());
706
707 // Find all the slots that we need to preserve f2
708 for (int i = 0; i < ik->methods()->length(); i++) {
709 Method* m = ik->methods()->at(i);
710 RawBytecodeStream bcs(m);
711 while (!bcs.is_last_bytecode()) {
712 Bytecodes::Code opcode = bcs.raw_next();
713 switch (opcode) {
714 case Bytecodes::_invokedynamic: {
715 int index = Bytes::get_native_u4(bcs.bcp() + 1);
716 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
717 f2_used[cp_cache_index] = 1;
718 }
719 break;
720 case Bytecodes::_invokehandle: {
721 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
722 f2_used[cp_cache_index] = 1;
723 }
724 break;
725 default:
726 break;
727 }
728 }
729 }
730
731 if (check_only) {
732 DEBUG_ONLY(
733 for (int i=0; i<length(); i++) {
734 entry_at(i)->verify_just_initialized(f2_used[i]);
735 })
736 } else {
737 for (int i=0; i<length(); i++) {
738 entry_at(i)->reinitialize(f2_used[i]);
739 }
740 }
741 }
742
743 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
744 assert(!is_shared(), "shared caches are not deallocated");
745 data->remove_handle(_resolved_references);
746 set_resolved_references(NULL);
747 MetadataFactory::free_array<u2>(data, _reference_map);
748 set_reference_map(NULL);
749 }
750
751 #if INCLUDE_CDS_JAVA_HEAP
752 oop ConstantPoolCache::archived_references() {
753 if (CompressedOops::is_null(_archived_references)) {
754 return NULL;
755 }
756 return MetaspaceShared::materialize_archived_object(_archived_references);
757 }
758
759 void ConstantPoolCache::set_archived_references(oop o) {
760 assert(DumpSharedSpaces, "called only during runtime");
761 _archived_references = CompressedOops::encode(o);
762 }
763 #endif
764
765 #if INCLUDE_JVMTI
766 // RedefineClasses() API support:
767 // If any entry of this ConstantPoolCache points to any of
768 // old_methods, replace it with the corresponding new_method.
769 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
770 for (int i = 0; i < length(); i++) {
771 ConstantPoolCacheEntry* entry = entry_at(i);
772 Method* old_method = entry->get_interesting_method_entry(holder);
773 if (old_method == NULL || !old_method->is_old()) {
774 continue; // skip uninteresting entries
775 }
776 if (old_method->is_deleted()) {
777 // clean up entries with deleted methods
778 entry->initialize_entry(entry->constant_pool_index());
779 continue;
780 }
781 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
782
783 assert(new_method != NULL, "method_with_idnum() should not be NULL");
784 assert(old_method != new_method, "sanity check");
785
786 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
787 }
788 }
789
790 // the constant pool cache should never contain old or obsolete methods
791 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
792 for (int i = 1; i < length(); i++) {
793 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
794 !entry_at(i)->check_no_old_or_obsolete_entries()) {
795 return false;
796 }
797 }
798 return true;
799 }
800
801 void ConstantPoolCache::dump_cache() {
802 for (int i = 1; i < length(); i++) {
803 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
804 entry_at(i)->print(tty, i);
805 }
806 }
807 }
808 #endif // INCLUDE_JVMTI
809
810 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
811 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
812 it->push(&_constant_pool);
813 it->push(&_reference_map);
814 }
815
816 // Printing
817
818 void ConstantPoolCache::print_on(outputStream* st) const {
819 assert(is_constantPoolCache(), "obj must be constant pool cache");
820 st->print_cr("%s", internal_name());
821 // print constant pool cache entries
822 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
823 }
824
825 void ConstantPoolCache::print_value_on(outputStream* st) const {
826 assert(is_constantPoolCache(), "obj must be constant pool cache");
827 st->print("cache [%d]", length());
828 print_address_on(st);
829 st->print(" for ");
830 constant_pool()->print_value_on(st);
831 }
832
833
834 // Verification
835
836 void ConstantPoolCache::verify_on(outputStream* st) {
837 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
838 // print constant pool cache entries
839 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
840 }