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 bool do_resolve = true;
256 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
257 // has to be checked that it is a subclass of the current class every time this bytecode
258 // is executed.
259 if (invoke_code == Bytecodes::_invokespecial && sender_is_interface &&
260 method->name() != vmSymbols::object_initializer_name()) {
261 do_resolve = false;
262 }
263 // Don't mark invokestatic to method as resolved if the holder class has not yet completed
264 // initialization. An invokestatic must only proceed if the class is initialized, but if
265 // we resolve it before then that class initialization check is skipped.
266 if (invoke_code == Bytecodes::_invokestatic && !method->method_holder()->is_initialized()) {
267 do_resolve = false;
268 }
269 if (do_resolve) {
270 set_bytecode_1(invoke_code);
271 }
272 } else if (byte_no == 2) {
273 if (change_to_virtual) {
274 assert(invoke_code == Bytecodes::_invokeinterface, "");
275 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
276 //
277 // Workaround for the case where we encounter an invokeinterface, but we
278 // should really have an _invokevirtual since the resolved method is a
279 // virtual method in java.lang.Object. This is a corner case in the spec
280 // but is presumably legal. javac does not generate this code.
281 //
282 // We do not set bytecode_1() to _invokeinterface, because that is the
283 // bytecode # used by the interpreter to see if it is resolved. In this
284 // case, the method gets reresolved with caller for each interface call
285 // because the actual selected method may not be public.
286 //
287 // We set bytecode_2() to _invokevirtual.
288 // See also interpreterRuntime.cpp. (8/25/2000)
289 } else {
290 assert(invoke_code == Bytecodes::_invokevirtual ||
291 (invoke_code == Bytecodes::_invokeinterface &&
292 ((method->is_private() ||
293 (method->is_final() && method->method_holder() == SystemDictionary::Object_klass())))),
294 "unexpected invocation mode");
295 if (invoke_code == Bytecodes::_invokeinterface &&
296 (method->is_private() || method->is_final())) {
297 // We set bytecode_1() to _invokeinterface, because that is the
298 // bytecode # used by the interpreter to see if it is resolved.
299 // We set bytecode_2() to _invokevirtual.
300 set_bytecode_1(invoke_code);
301 }
302 }
303 // set up for invokevirtual, even if linking for invokeinterface also:
304 set_bytecode_2(Bytecodes::_invokevirtual);
305 } else {
306 ShouldNotReachHere();
307 }
308 NOT_PRODUCT(verify(tty));
309 }
310
311 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
312 bool sender_is_interface) {
313 int index = Method::nonvirtual_vtable_index;
314 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
315 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
316 }
317
318 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
319 // either the method is a miranda or its holder should accept the given index
320 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
321 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
322 set_direct_or_vtable_call(invoke_code, method, index, false);
323 }
324
325 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
326 Klass* referenced_klass,
327 const methodHandle& method, int index) {
328 assert(method->method_holder()->verify_itable_index(index), "");
329 assert(invoke_code == Bytecodes::_invokeinterface, "");
330 InstanceKlass* interf = method->method_holder();
331 assert(interf->is_interface(), "must be an interface");
332 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
333 set_f1(referenced_klass);
334 set_f2((intx)method());
335 set_method_flags(as_TosState(method->result_type()),
336 0, // no option bits
337 method()->size_of_parameters());
338 set_bytecode_1(Bytecodes::_invokeinterface);
339 }
340
341
342 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
343 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
344 }
345
346 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
347 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
348 }
349
350 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
351 Bytecodes::Code invoke_code,
352 const CallInfo &call_info) {
353 // NOTE: This CPCE can be the subject of data races.
354 // There are three words to update: flags, refs[f2], f1 (in that order).
355 // Writers must store all other values before f1.
356 // Readers must test f1 first for non-null before reading other fields.
357 // Competing writers must acquire exclusive access via a lock.
358 // A losing writer waits on the lock until the winner writes f1 and leaves
359 // the lock, so that when the losing writer returns, he can use the linked
360 // cache entry.
361
362 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
363 // Use the resolved_references() lock for this cpCache entry.
364 // resolved_references are created for all classes with Invokedynamic, MethodHandle
365 // or MethodType constant pool cache entries.
366 assert(resolved_references() != NULL,
367 "a resolved_references array should have been created for this class");
368 ObjectLocker ol(resolved_references, Thread::current());
369 if (!is_f1_null()) {
370 return;
371 }
372
373 if (indy_resolution_failed()) {
374 // Before we got here, another thread got a LinkageError exception during
375 // resolution. Ignore our success and throw their exception.
376 ConstantPoolCache* cpCache = cpool->cache();
377 int index = -1;
378 for (int i = 0; i < cpCache->length(); i++) {
379 if (cpCache->entry_at(i) == this) {
380 index = i;
381 break;
382 }
383 }
384 guarantee(index >= 0, "Didn't find cpCache entry!");
385 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
386 ConstantPool::encode_invokedynamic_index(index));
387 Thread* THREAD = Thread::current();
388 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
389 return;
390 }
391
392 const methodHandle adapter = call_info.resolved_method();
393 const Handle appendix = call_info.resolved_appendix();
394 const Handle method_type = call_info.resolved_method_type();
395 const bool has_appendix = appendix.not_null();
396 const bool has_method_type = method_type.not_null();
397
398 // Write the flags.
399 set_method_flags(as_TosState(adapter->result_type()),
400 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
401 ((has_method_type ? 1 : 0) << has_method_type_shift) |
402 ( 1 << is_final_shift ),
403 adapter->size_of_parameters());
404
405 if (TraceInvokeDynamic) {
406 ttyLocker ttyl;
407 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ",
408 invoke_code,
409 p2i(appendix()), (has_appendix ? "" : " (unused)"),
410 p2i(method_type()), (has_method_type ? "" : " (unused)"),
411 p2i(adapter()));
412 adapter->print();
413 if (has_appendix) appendix()->print();
414 }
415
416 // Method handle invokes and invokedynamic sites use both cp cache words.
417 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
418 // In the general case, this could be the call site's MethodType,
419 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
420 // f1 contains the adapter method which manages the actual call.
421 // In the general case, this is a compiled LambdaForm.
422 // (The Java code is free to optimize these calls by binding other
423 // sorts of methods and appendices to call sites.)
424 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
425 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
426 // Even with the appendix, the method will never take more than 255 parameter slots.
427 //
428 // This means that given a call site like (List)mh.invoke("foo"),
429 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
430 // not '(Ljava/lang/String;)Ljava/util/List;'.
431 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
432 // This allows us to create fewer Methods, while keeping type safety.
433 //
434
435 // Store appendix, if any.
436 if (has_appendix) {
437 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
438 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
439 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
440 resolved_references->obj_at_put(appendix_index, appendix());
441 }
442
443 // Store MethodType, if any.
444 if (has_method_type) {
445 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
446 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
447 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
448 resolved_references->obj_at_put(method_type_index, method_type());
449 }
450
451 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
452
453 // The interpreter assembly code does not check byte_2,
454 // but it is used by is_resolved, method_if_resolved, etc.
455 set_bytecode_1(invoke_code);
456 NOT_PRODUCT(verify(tty));
457 if (TraceInvokeDynamic) {
458 ttyLocker ttyl;
459 this->print(tty, 0);
460 }
461 }
462
463 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
464 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
465
466 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
467 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
468 "No LinkageError exception");
469
470 // Use the resolved_references() lock for this cpCache entry.
471 // resolved_references are created for all classes with Invokedynamic, MethodHandle
472 // or MethodType constant pool cache entries.
473 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
474 assert(resolved_references() != NULL,
475 "a resolved_references array should have been created for this class");
476 ObjectLocker ol(resolved_references, THREAD);
477
478 // if f1 is not null or the indy_resolution_failed flag is set then another
479 // thread either succeeded in resolving the method or got a LinkageError
480 // exception, before this thread was able to record its failure. So, clear
481 // this thread's exception and return false so caller can use the earlier
482 // thread's result.
483 if (!is_f1_null() || indy_resolution_failed()) {
484 CLEAR_PENDING_EXCEPTION;
485 return false;
486 }
487
488 Symbol* error = PENDING_EXCEPTION->klass()->name();
489 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
490 assert(message != NULL, "Missing detail message");
491
492 SystemDictionary::add_resolution_error(cpool, index, error, message);
493 set_indy_resolution_failed();
494 return true;
495 }
496
497 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
498 // Decode the action of set_method and set_interface_call
499 Bytecodes::Code invoke_code = bytecode_1();
500 if (invoke_code != (Bytecodes::Code)0) {
501 Metadata* f1 = f1_ord();
502 if (f1 != NULL) {
503 switch (invoke_code) {
504 case Bytecodes::_invokeinterface:
505 assert(f1->is_klass(), "");
506 return klassItable::method_for_itable_index((Klass*)f1, f2_as_index());
507 case Bytecodes::_invokestatic:
508 case Bytecodes::_invokespecial:
509 assert(!has_appendix(), "");
510 case Bytecodes::_invokehandle:
511 case Bytecodes::_invokedynamic:
512 assert(f1->is_method(), "");
513 return (Method*)f1;
514 default:
515 break;
516 }
517 }
518 }
519 invoke_code = bytecode_2();
520 if (invoke_code != (Bytecodes::Code)0) {
521 switch (invoke_code) {
522 case Bytecodes::_invokevirtual:
523 if (is_vfinal()) {
524 // invokevirtual
525 Method* m = f2_as_vfinal_method();
526 assert(m->is_method(), "");
527 return m;
528 } else {
529 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
530 if (cpool->tag_at(holder_index).is_klass()) {
531 Klass* klass = cpool->resolved_klass_at(holder_index);
532 return klass->method_at_vtable(f2_as_index());
533 }
534 }
535 break;
536 default:
537 break;
538 }
539 }
540 return NULL;
541 }
542
543
544 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
545 if (!has_appendix())
546 return NULL;
547 const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset;
548 objArrayOop resolved_references = cpool->resolved_references();
549 return resolved_references->obj_at(ref_index);
550 }
551
552
553 oop ConstantPoolCacheEntry::method_type_if_resolved(const constantPoolHandle& cpool) {
554 if (!has_method_type())
555 return NULL;
556 const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset;
557 objArrayOop resolved_references = cpool->resolved_references();
558 return resolved_references->obj_at(ref_index);
559 }
560
561
562 #if INCLUDE_JVMTI
563
564 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
565 if (log_is_enabled(Info, redefine, class, update)) {
566 ResourceMark rm;
567 if (!(*trace_name_printed)) {
568 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
569 *trace_name_printed = true;
570 }
571 log_debug(redefine, class, update, constantpool)
572 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string());
573 }
574 }
575
576 // RedefineClasses() API support:
577 // If this ConstantPoolCacheEntry refers to old_method then update it
578 // to refer to new_method.
579 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
580 Method* new_method, bool * trace_name_printed) {
581
582 if (is_vfinal()) {
583 // virtual and final so _f2 contains method ptr instead of vtable index
584 if (f2_as_vfinal_method() == old_method) {
585 // match old_method so need an update
586 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
587 _f2 = (intptr_t)new_method;
588 log_adjust("vfinal", old_method, new_method, trace_name_printed);
589 }
590 return;
591 }
592
593 assert (_f1 != NULL, "should not call with uninteresting entry");
594
595 if (!(_f1->is_method())) {
596 // _f1 is a Klass* for an interface, _f2 is the method
597 if (f2_as_interface_method() == old_method) {
598 _f2 = (intptr_t)new_method;
599 log_adjust("interface", old_method, new_method, trace_name_printed);
600 }
601 } else if (_f1 == old_method) {
602 _f1 = new_method;
603 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
604 }
605 }
606
607 // a constant pool cache entry should never contain old or obsolete methods
608 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
609 Method* m = get_interesting_method_entry(NULL);
610 // return false if m refers to a non-deleted old or obsolete method
611 if (m != NULL) {
612 assert(m->is_valid() && m->is_method(), "m is a valid method");
613 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
614 } else {
615 return true;
616 }
617 }
618
619 Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) {
620 if (!is_method_entry()) {
621 // not a method entry so not interesting by default
622 return NULL;
623 }
624 Method* m = NULL;
625 if (is_vfinal()) {
626 // virtual and final so _f2 contains method ptr instead of vtable index
627 m = f2_as_vfinal_method();
628 } else if (is_f1_null()) {
629 // NULL _f1 means this is a virtual entry so also not interesting
630 return NULL;
631 } else {
632 if (!(_f1->is_method())) {
633 // _f1 is a Klass* for an interface
634 m = f2_as_interface_method();
635 } else {
636 m = f1_as_method();
637 }
638 }
639 assert(m != NULL && m->is_method(), "sanity check");
640 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
641 // robustness for above sanity checks or method is not in
642 // the interesting class
643 return NULL;
644 }
645 // the method is in the interesting class so the entry is interesting
646 return m;
647 }
648 #endif // INCLUDE_JVMTI
649
650 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
651 // print separator
652 if (index == 0) st->print_cr(" -------------");
653 // print entry
654 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
655 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
656 constant_pool_index());
657 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
658 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
659 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
660 st->print_cr(" -------------");
661 }
662
663 void ConstantPoolCacheEntry::verify(outputStream* st) const {
664 // not implemented yet
665 }
666
667 // Implementation of ConstantPoolCache
668
669 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
670 const intStack& index_map,
671 const intStack& invokedynamic_index_map,
672 const intStack& invokedynamic_map, TRAPS) {
673
674 const int length = index_map.length() + invokedynamic_index_map.length();
675 int size = ConstantPoolCache::size(length);
676
677 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
678 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
679 }
680
681 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
682 const intArray& invokedynamic_inverse_index_map,
683 const intArray& invokedynamic_references_map) {
684 for (int i = 0; i < inverse_index_map.length(); i++) {
685 ConstantPoolCacheEntry* e = entry_at(i);
686 int original_index = inverse_index_map.at(i);
687 e->initialize_entry(original_index);
688 assert(entry_at(i) == e, "sanity");
689 }
690
691 // Append invokedynamic entries at the end
692 int invokedynamic_offset = inverse_index_map.length();
693 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
694 int offset = i + invokedynamic_offset;
695 ConstantPoolCacheEntry* e = entry_at(offset);
696 int original_index = invokedynamic_inverse_index_map.at(i);
697 e->initialize_entry(original_index);
698 assert(entry_at(offset) == e, "sanity");
699 }
700
701 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
702 const int cpci = invokedynamic_references_map.at(ref);
703 if (cpci >= 0) {
704 #ifdef ASSERT
705 // invokedynamic and invokehandle have more entries; check if they
706 // all point to the same constant pool cache entry.
707 for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
708 const int cpci_next = invokedynamic_references_map.at(ref + entry);
709 assert(cpci == cpci_next, "%d == %d", cpci, cpci_next);
710 }
711 #endif
712 entry_at(cpci)->initialize_resolved_reference_index(ref);
713 ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries
714 }
715 }
716 }
717
718 void ConstantPoolCache::verify_just_initialized() {
719 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
720 }
721
722 void ConstantPoolCache::remove_unshareable_info() {
723 walk_entries_for_initialization(/*check_only = */ false);
724 }
725
726 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
727 assert(DumpSharedSpaces, "sanity");
728 // When dumping the archive, we want to clean up the ConstantPoolCache
729 // to remove any effect of linking due to the execution of Java code --
730 // each ConstantPoolCacheEntry will have the same contents as if
731 // ConstantPoolCache::initialize has just returned:
732 //
733 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
734 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
735 // - All other bits in the entries are cleared to zero.
736 ResourceMark rm;
737
738 InstanceKlass* ik = constant_pool()->pool_holder();
739 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
740 memset(f2_used, 0, sizeof(bool) * length());
741
742 // Find all the slots that we need to preserve f2
743 for (int i = 0; i < ik->methods()->length(); i++) {
744 Method* m = ik->methods()->at(i);
745 RawBytecodeStream bcs(m);
746 while (!bcs.is_last_bytecode()) {
747 Bytecodes::Code opcode = bcs.raw_next();
748 switch (opcode) {
749 case Bytecodes::_invokedynamic: {
750 int index = Bytes::get_native_u4(bcs.bcp() + 1);
751 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
752 f2_used[cp_cache_index] = 1;
753 }
754 break;
755 case Bytecodes::_invokehandle: {
756 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
757 f2_used[cp_cache_index] = 1;
758 }
759 break;
760 default:
761 break;
762 }
763 }
764 }
765
766 if (check_only) {
767 DEBUG_ONLY(
768 for (int i=0; i<length(); i++) {
769 entry_at(i)->verify_just_initialized(f2_used[i]);
770 })
771 } else {
772 for (int i=0; i<length(); i++) {
773 entry_at(i)->reinitialize(f2_used[i]);
774 }
775 }
776 }
777
778 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
779 assert(!is_shared(), "shared caches are not deallocated");
780 data->remove_handle(_resolved_references);
781 set_resolved_references(NULL);
782 MetadataFactory::free_array<u2>(data, _reference_map);
783 set_reference_map(NULL);
784 }
785
786 #if INCLUDE_CDS_JAVA_HEAP
787 oop ConstantPoolCache::archived_references() {
788 if (CompressedOops::is_null(_archived_references)) {
789 return NULL;
790 }
791 return MetaspaceShared::materialize_archived_object(CompressedOops::decode_not_null(_archived_references));
792 }
793
794 void ConstantPoolCache::set_archived_references(oop o) {
795 assert(DumpSharedSpaces, "called only during runtime");
796 _archived_references = CompressedOops::encode(o);
797 }
798 #endif
799
800 #if INCLUDE_JVMTI
801 // RedefineClasses() API support:
802 // If any entry of this ConstantPoolCache points to any of
803 // old_methods, replace it with the corresponding new_method.
804 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
805 for (int i = 0; i < length(); i++) {
806 ConstantPoolCacheEntry* entry = entry_at(i);
807 Method* old_method = entry->get_interesting_method_entry(holder);
808 if (old_method == NULL || !old_method->is_old()) {
809 continue; // skip uninteresting entries
810 }
811 if (old_method->is_deleted()) {
812 // clean up entries with deleted methods
813 entry->initialize_entry(entry->constant_pool_index());
814 continue;
815 }
816 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
817
818 assert(new_method != NULL, "method_with_idnum() should not be NULL");
819 assert(old_method != new_method, "sanity check");
820
821 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
822 }
823 }
824
825 // the constant pool cache should never contain old or obsolete methods
826 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
827 for (int i = 1; i < length(); i++) {
828 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
829 !entry_at(i)->check_no_old_or_obsolete_entries()) {
830 return false;
831 }
832 }
833 return true;
834 }
835
836 void ConstantPoolCache::dump_cache() {
837 for (int i = 1; i < length(); i++) {
838 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
839 entry_at(i)->print(tty, i);
840 }
841 }
842 }
843 #endif // INCLUDE_JVMTI
844
845 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
846 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
847 it->push(&_constant_pool);
848 it->push(&_reference_map);
849 }
850
851 // Printing
852
853 void ConstantPoolCache::print_on(outputStream* st) const {
854 assert(is_constantPoolCache(), "obj must be constant pool cache");
855 st->print_cr("%s", internal_name());
856 // print constant pool cache entries
857 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
858 }
859
860 void ConstantPoolCache::print_value_on(outputStream* st) const {
861 assert(is_constantPoolCache(), "obj must be constant pool cache");
862 st->print("cache [%d]", length());
863 print_address_on(st);
864 st->print(" for ");
865 constant_pool()->print_value_on(st);
866 }
867
868
869 // Verification
870
871 void ConstantPoolCache::verify_on(outputStream* st) {
872 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
873 // print constant pool cache entries
874 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
875 }