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
178 switch (invoke_code) {
179 case Bytecodes::_invokeinterface:
180 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
181 // instruction somehow links to a non-interface method (in Object).
182 // In that case, the method has no itable index and must be invoked as a virtual.
183 // Set a flag to keep track of this corner case.
184 assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
185 change_to_virtual = true;
186
187 // ...and fall through as if we were handling invokevirtual:
188 case Bytecodes::_invokevirtual:
189 {
190 if (!is_vtable_call) {
191 assert(method->can_be_statically_bound(), "");
192 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
193 set_method_flags(as_TosState(method->result_type()),
194 ( 1 << is_vfinal_shift) |
195 ((method->is_final_method() ? 1 : 0) << is_final_shift) |
196 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
197 method()->size_of_parameters());
198 set_f2_as_vfinal_method(method());
199 } else {
200 assert(!method->can_be_statically_bound(), "");
201 assert(vtable_index >= 0, "valid index");
202 assert(!method->is_final_method(), "sanity");
203 set_method_flags(as_TosState(method->result_type()),
204 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
205 method()->size_of_parameters());
206 set_f2(vtable_index);
207 }
208 byte_no = 2;
209 break;
210 }
211
212 case Bytecodes::_invokespecial:
213 case Bytecodes::_invokestatic:
214 assert(!is_vtable_call, "");
215 // Note: Read and preserve the value of the is_vfinal flag on any
216 // invokevirtual bytecode shared with this constant pool cache entry.
217 // It is cheap and safe to consult is_vfinal() at all times.
218 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
219 set_method_flags(as_TosState(method->result_type()),
220 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
221 ((method->is_final_method() ? 1 : 0) << is_final_shift),
222 method()->size_of_parameters());
223 set_f1(method());
224 byte_no = 1;
225 break;
226 default:
227 ShouldNotReachHere();
228 break;
229 }
230
231 // Note: byte_no also appears in TemplateTable::resolve.
232 if (byte_no == 1) {
233 assert(invoke_code != Bytecodes::_invokevirtual &&
234 invoke_code != Bytecodes::_invokeinterface, "");
235 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
236 // has to be checked that it is a subclass of the current class every time this bytecode
237 // is executed.
238 if (invoke_code != Bytecodes::_invokespecial || !sender_is_interface ||
239 method->name() == vmSymbols::object_initializer_name()) {
240 set_bytecode_1(invoke_code);
241 }
242 } else if (byte_no == 2) {
243 if (change_to_virtual) {
244 assert(invoke_code == Bytecodes::_invokeinterface, "");
245 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
246 //
247 // Workaround for the case where we encounter an invokeinterface, but we
248 // should really have an _invokevirtual since the resolved method is a
249 // virtual method in java.lang.Object. This is a corner case in the spec
250 // but is presumably legal. javac does not generate this code.
251 //
252 // We do not set bytecode_1() to _invokeinterface, because that is the
253 // bytecode # used by the interpreter to see if it is resolved. In this
254 // case, the method gets reresolved with caller for each interface call
255 // because the actual selected method may not be public.
256 //
257 // We set bytecode_2() to _invokevirtual.
258 // See also interpreterRuntime.cpp. (8/25/2000)
259 } else {
260 assert(invoke_code == Bytecodes::_invokevirtual, "");
261 }
262 // set up for invokevirtual, even if linking for invokeinterface also:
263 set_bytecode_2(Bytecodes::_invokevirtual);
264 } else {
265 ShouldNotReachHere();
266 }
267 NOT_PRODUCT(verify(tty));
268 }
269
270 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
271 bool sender_is_interface) {
272 int index = Method::nonvirtual_vtable_index;
273 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
274 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
275 }
276
277 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
278 // either the method is a miranda or its holder should accept the given index
279 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
280 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
281 set_direct_or_vtable_call(invoke_code, method, index, false);
282 }
283
284 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
285 Klass* referenced_klass,
286 const methodHandle& method, int index) {
287 assert(method->method_holder()->verify_itable_index(index), "");
288 assert(invoke_code == Bytecodes::_invokeinterface, "");
289 InstanceKlass* interf = method->method_holder();
290 assert(interf->is_interface(), "must be an interface");
291 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
292 set_f1(referenced_klass);
293 set_f2((intx)method());
294 set_method_flags(as_TosState(method->result_type()),
295 0, // no option bits
296 method()->size_of_parameters());
297 set_bytecode_1(Bytecodes::_invokeinterface);
298 }
299
300
301 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
302 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
303 }
304
305 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
306 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
307 }
308
309 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
310 Bytecodes::Code invoke_code,
311 const CallInfo &call_info) {
312 // NOTE: This CPCE can be the subject of data races.
313 // There are three words to update: flags, refs[f2], f1 (in that order).
314 // Writers must store all other values before f1.
315 // Readers must test f1 first for non-null before reading other fields.
316 // Competing writers must acquire exclusive access via a lock.
317 // A losing writer waits on the lock until the winner writes f1 and leaves
318 // the lock, so that when the losing writer returns, he can use the linked
319 // cache entry.
320
321 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
322 // Use the resolved_references() lock for this cpCache entry.
323 // resolved_references are created for all classes with Invokedynamic, MethodHandle
324 // or MethodType constant pool cache entries.
325 assert(resolved_references() != NULL,
326 "a resolved_references array should have been created for this class");
327 ObjectLocker ol(resolved_references, Thread::current());
328 if (!is_f1_null()) {
329 return;
330 }
331
332 if (indy_resolution_failed()) {
333 // Before we got here, another thread got a LinkageError exception during
334 // resolution. Ignore our success and throw their exception.
335 ConstantPoolCache* cpCache = cpool->cache();
336 int index = -1;
337 for (int i = 0; i < cpCache->length(); i++) {
338 if (cpCache->entry_at(i) == this) {
339 index = i;
340 break;
341 }
342 }
343 guarantee(index >= 0, "Didn't find cpCache entry!");
344 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
345 ConstantPool::encode_invokedynamic_index(index));
346 Thread* THREAD = Thread::current();
347 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
348 return;
349 }
350
351 const methodHandle adapter = call_info.resolved_method();
352 const Handle appendix = call_info.resolved_appendix();
353 const Handle method_type = call_info.resolved_method_type();
354 const bool has_appendix = appendix.not_null();
355 const bool has_method_type = method_type.not_null();
356
357 // Write the flags.
358 set_method_flags(as_TosState(adapter->result_type()),
359 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
360 ((has_method_type ? 1 : 0) << has_method_type_shift) |
361 ( 1 << is_final_shift ),
362 adapter->size_of_parameters());
363
364 if (TraceInvokeDynamic) {
365 ttyLocker ttyl;
366 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ",
367 invoke_code,
368 p2i(appendix()), (has_appendix ? "" : " (unused)"),
369 p2i(method_type()), (has_method_type ? "" : " (unused)"),
370 p2i(adapter()));
371 adapter->print();
372 if (has_appendix) appendix()->print();
373 }
374
375 // Method handle invokes and invokedynamic sites use both cp cache words.
376 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
377 // In the general case, this could be the call site's MethodType,
378 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
379 // f1 contains the adapter method which manages the actual call.
380 // In the general case, this is a compiled LambdaForm.
381 // (The Java code is free to optimize these calls by binding other
382 // sorts of methods and appendices to call sites.)
383 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
384 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
385 // Even with the appendix, the method will never take more than 255 parameter slots.
386 //
387 // This means that given a call site like (List)mh.invoke("foo"),
388 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
389 // not '(Ljava/lang/String;)Ljava/util/List;'.
390 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
391 // This allows us to create fewer Methods, while keeping type safety.
392 //
393
394 // Store appendix, if any.
395 if (has_appendix) {
396 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
397 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
398 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
399 resolved_references->obj_at_put(appendix_index, appendix());
400 }
401
402 // Store MethodType, if any.
403 if (has_method_type) {
404 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
405 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
406 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
407 resolved_references->obj_at_put(method_type_index, method_type());
408 }
409
410 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
411
412 // The interpreter assembly code does not check byte_2,
413 // but it is used by is_resolved, method_if_resolved, etc.
414 set_bytecode_1(invoke_code);
415 NOT_PRODUCT(verify(tty));
416 if (TraceInvokeDynamic) {
417 ttyLocker ttyl;
418 this->print(tty, 0);
419 }
420 }
421
422 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
423 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
424
425 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
426 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
427 "No LinkageError exception");
428
429 // Use the resolved_references() lock for this cpCache entry.
430 // resolved_references are created for all classes with Invokedynamic, MethodHandle
431 // or MethodType constant pool cache entries.
432 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
433 assert(resolved_references() != NULL,
434 "a resolved_references array should have been created for this class");
435 ObjectLocker ol(resolved_references, THREAD);
436
437 // if f1 is not null or the indy_resolution_failed flag is set then another
438 // thread either succeeded in resolving the method or got a LinkageError
439 // exception, before this thread was able to record its failure. So, clear
440 // this thread's exception and return false so caller can use the earlier
441 // thread's result.
442 if (!is_f1_null() || indy_resolution_failed()) {
443 CLEAR_PENDING_EXCEPTION;
444 return false;
445 }
446
447 Symbol* error = PENDING_EXCEPTION->klass()->name();
448 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
449 assert(message != NULL, "Missing detail message");
450
451 SystemDictionary::add_resolution_error(cpool, index, error, message);
452 set_indy_resolution_failed();
453 return true;
454 }
455
456 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
457 // Decode the action of set_method and set_interface_call
458 Bytecodes::Code invoke_code = bytecode_1();
459 if (invoke_code != (Bytecodes::Code)0) {
460 Metadata* f1 = f1_ord();
461 if (f1 != NULL) {
462 switch (invoke_code) {
463 case Bytecodes::_invokeinterface:
464 assert(f1->is_klass(), "");
465 return klassItable::method_for_itable_index((Klass*)f1, f2_as_index());
466 case Bytecodes::_invokestatic:
467 case Bytecodes::_invokespecial:
468 assert(!has_appendix(), "");
469 case Bytecodes::_invokehandle:
470 case Bytecodes::_invokedynamic:
471 assert(f1->is_method(), "");
472 return (Method*)f1;
473 default:
474 break;
475 }
476 }
477 }
478 invoke_code = bytecode_2();
479 if (invoke_code != (Bytecodes::Code)0) {
480 switch (invoke_code) {
481 case Bytecodes::_invokevirtual:
482 if (is_vfinal()) {
483 // invokevirtual
484 Method* m = f2_as_vfinal_method();
485 assert(m->is_method(), "");
486 return m;
487 } else {
488 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
489 if (cpool->tag_at(holder_index).is_klass()) {
490 Klass* klass = cpool->resolved_klass_at(holder_index);
491 return klass->method_at_vtable(f2_as_index());
492 }
493 }
494 break;
495 default:
496 break;
497 }
498 }
499 return NULL;
500 }
501
502
503 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
504 if (!has_appendix())
505 return NULL;
506 const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset;
507 objArrayOop resolved_references = cpool->resolved_references();
508 return resolved_references->obj_at(ref_index);
509 }
510
511
512 oop ConstantPoolCacheEntry::method_type_if_resolved(const constantPoolHandle& cpool) {
513 if (!has_method_type())
514 return NULL;
515 const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset;
516 objArrayOop resolved_references = cpool->resolved_references();
517 return resolved_references->obj_at(ref_index);
518 }
519
520
521 #if INCLUDE_JVMTI
522
523 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
524 if (log_is_enabled(Info, redefine, class, update)) {
525 ResourceMark rm;
526 if (!(*trace_name_printed)) {
527 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
528 *trace_name_printed = true;
529 }
530 log_debug(redefine, class, update, constantpool)
531 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string());
532 }
533 }
534
535 // RedefineClasses() API support:
536 // If this ConstantPoolCacheEntry refers to old_method then update it
537 // to refer to new_method.
538 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
539 Method* new_method, bool * trace_name_printed) {
540
541 if (is_vfinal()) {
542 // virtual and final so _f2 contains method ptr instead of vtable index
543 if (f2_as_vfinal_method() == old_method) {
544 // match old_method so need an update
545 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
546 _f2 = (intptr_t)new_method;
547 log_adjust("vfinal", old_method, new_method, trace_name_printed);
548 }
549 return;
550 }
551
552 assert (_f1 != NULL, "should not call with uninteresting entry");
553
554 if (!(_f1->is_method())) {
555 // _f1 is a Klass* for an interface, _f2 is the method
556 if (f2_as_interface_method() == old_method) {
557 _f2 = (intptr_t)new_method;
558 log_adjust("interface", old_method, new_method, trace_name_printed);
559 }
560 } else if (_f1 == old_method) {
561 _f1 = new_method;
562 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
563 }
564 }
565
566 // a constant pool cache entry should never contain old or obsolete methods
567 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
568 Method* m = get_interesting_method_entry(NULL);
569 // return false if m refers to a non-deleted old or obsolete method
570 if (m != NULL) {
571 assert(m->is_valid() && m->is_method(), "m is a valid method");
572 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
573 } else {
574 return true;
575 }
576 }
577
578 Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) {
579 if (!is_method_entry()) {
580 // not a method entry so not interesting by default
581 return NULL;
582 }
583 Method* m = NULL;
584 if (is_vfinal()) {
585 // virtual and final so _f2 contains method ptr instead of vtable index
586 m = f2_as_vfinal_method();
587 } else if (is_f1_null()) {
588 // NULL _f1 means this is a virtual entry so also not interesting
589 return NULL;
590 } else {
591 if (!(_f1->is_method())) {
592 // _f1 is a Klass* for an interface
593 m = f2_as_interface_method();
594 } else {
595 m = f1_as_method();
596 }
597 }
598 assert(m != NULL && m->is_method(), "sanity check");
599 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
600 // robustness for above sanity checks or method is not in
601 // the interesting class
602 return NULL;
603 }
604 // the method is in the interesting class so the entry is interesting
605 return m;
606 }
607 #endif // INCLUDE_JVMTI
608
609 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
610 // print separator
611 if (index == 0) st->print_cr(" -------------");
612 // print entry
613 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
614 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
615 constant_pool_index());
616 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
617 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
618 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
619 st->print_cr(" -------------");
620 }
621
622 void ConstantPoolCacheEntry::verify(outputStream* st) const {
623 // not implemented yet
624 }
625
626 // Implementation of ConstantPoolCache
627
628 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
629 const intStack& index_map,
630 const intStack& invokedynamic_index_map,
631 const intStack& invokedynamic_map, TRAPS) {
632
633 const int length = index_map.length() + invokedynamic_index_map.length();
634 int size = ConstantPoolCache::size(length);
635
636 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
637 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
638 }
639
640 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
641 const intArray& invokedynamic_inverse_index_map,
642 const intArray& invokedynamic_references_map) {
643 for (int i = 0; i < inverse_index_map.length(); i++) {
644 ConstantPoolCacheEntry* e = entry_at(i);
645 int original_index = inverse_index_map.at(i);
646 e->initialize_entry(original_index);
647 assert(entry_at(i) == e, "sanity");
648 }
649
650 // Append invokedynamic entries at the end
651 int invokedynamic_offset = inverse_index_map.length();
652 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
653 int offset = i + invokedynamic_offset;
654 ConstantPoolCacheEntry* e = entry_at(offset);
655 int original_index = invokedynamic_inverse_index_map.at(i);
656 e->initialize_entry(original_index);
657 assert(entry_at(offset) == e, "sanity");
658 }
659
660 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
661 const int cpci = invokedynamic_references_map.at(ref);
662 if (cpci >= 0) {
663 #ifdef ASSERT
664 // invokedynamic and invokehandle have more entries; check if they
665 // all point to the same constant pool cache entry.
666 for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
667 const int cpci_next = invokedynamic_references_map.at(ref + entry);
668 assert(cpci == cpci_next, "%d == %d", cpci, cpci_next);
669 }
670 #endif
671 entry_at(cpci)->initialize_resolved_reference_index(ref);
672 ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries
673 }
674 }
675 }
676
677 void ConstantPoolCache::verify_just_initialized() {
678 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
679 }
680
681 void ConstantPoolCache::remove_unshareable_info() {
682 walk_entries_for_initialization(/*check_only = */ false);
683 }
684
685 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
686 assert(DumpSharedSpaces, "sanity");
687 // When dumping the archive, we want to clean up the ConstantPoolCache
688 // to remove any effect of linking due to the execution of Java code --
689 // each ConstantPoolCacheEntry will have the same contents as if
690 // ConstantPoolCache::initialize has just returned:
691 //
692 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
693 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
694 // - All other bits in the entries are cleared to zero.
695 ResourceMark rm;
696
697 InstanceKlass* ik = constant_pool()->pool_holder();
698 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
699 memset(f2_used, 0, sizeof(bool) * length());
700
701 // Find all the slots that we need to preserve f2
702 for (int i = 0; i < ik->methods()->length(); i++) {
703 Method* m = ik->methods()->at(i);
704 RawBytecodeStream bcs(m);
705 while (!bcs.is_last_bytecode()) {
706 Bytecodes::Code opcode = bcs.raw_next();
707 switch (opcode) {
708 case Bytecodes::_invokedynamic: {
709 int index = Bytes::get_native_u4(bcs.bcp() + 1);
710 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
711 f2_used[cp_cache_index] = 1;
712 }
713 break;
714 case Bytecodes::_invokehandle: {
715 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
716 f2_used[cp_cache_index] = 1;
717 }
718 break;
719 default:
720 break;
721 }
722 }
723 }
724
725 if (check_only) {
726 DEBUG_ONLY(
727 for (int i=0; i<length(); i++) {
728 entry_at(i)->verify_just_initialized(f2_used[i]);
729 })
730 } else {
731 for (int i=0; i<length(); i++) {
732 entry_at(i)->reinitialize(f2_used[i]);
733 }
734 }
735 }
736
737 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
738 assert(!is_shared(), "shared caches are not deallocated");
739 data->remove_handle(_resolved_references);
740 set_resolved_references(NULL);
741 MetadataFactory::free_array<u2>(data, _reference_map);
742 set_reference_map(NULL);
743 }
744
745 #if INCLUDE_CDS_JAVA_HEAP
746 oop ConstantPoolCache::archived_references() {
747 if (CompressedOops::is_null(_archived_references)) {
748 return NULL;
749 }
750 return MetaspaceShared::unarchive_heap_object(CompressedOops::decode_not_null(_archived_references));
751 }
752
753 void ConstantPoolCache::set_archived_references(oop o) {
754 assert(DumpSharedSpaces, "called only during runtime");
755 _archived_references = CompressedOops::encode(o);
756 }
757 #endif
758
759 #if INCLUDE_JVMTI
760 // RedefineClasses() API support:
761 // If any entry of this ConstantPoolCache points to any of
762 // old_methods, replace it with the corresponding new_method.
763 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
764 for (int i = 0; i < length(); i++) {
765 ConstantPoolCacheEntry* entry = entry_at(i);
766 Method* old_method = entry->get_interesting_method_entry(holder);
767 if (old_method == NULL || !old_method->is_old()) {
768 continue; // skip uninteresting entries
769 }
770 if (old_method->is_deleted()) {
771 // clean up entries with deleted methods
772 entry->initialize_entry(entry->constant_pool_index());
773 continue;
774 }
775 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
776
777 assert(new_method != NULL, "method_with_idnum() should not be NULL");
778 assert(old_method != new_method, "sanity check");
779
780 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
781 }
782 }
783
784 // the constant pool cache should never contain old or obsolete methods
785 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
786 for (int i = 1; i < length(); i++) {
787 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
788 !entry_at(i)->check_no_old_or_obsolete_entries()) {
789 return false;
790 }
791 }
792 return true;
793 }
794
795 void ConstantPoolCache::dump_cache() {
796 for (int i = 1; i < length(); i++) {
797 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
798 entry_at(i)->print(tty, i);
799 }
800 }
801 }
802 #endif // INCLUDE_JVMTI
803
804 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
805 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
806 it->push(&_constant_pool);
807 it->push(&_reference_map);
808 }
809
810 // Printing
811
812 void ConstantPoolCache::print_on(outputStream* st) const {
813 assert(is_constantPoolCache(), "obj must be constant pool cache");
814 st->print_cr("%s", internal_name());
815 // print constant pool cache entries
816 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
817 }
818
819 void ConstantPoolCache::print_value_on(outputStream* st) const {
820 assert(is_constantPoolCache(), "obj must be constant pool cache");
821 st->print("cache [%d]", length());
822 print_address_on(st);
823 st->print(" for ");
824 constant_pool()->print_value_on(st);
825 }
826
827
828 // Verification
829
830 void ConstantPoolCache::verify_on(outputStream* st) {
831 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
832 // print constant pool cache entries
833 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
834 }