1 /*
2 * Copyright (c) 1998, 2017, 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/rewriter.hpp"
31 #include "logging/log.hpp"
32 #include "memory/metadataFactory.hpp"
33 #include "memory/metaspaceClosure.hpp"
34 #include "memory/resourceArea.hpp"
35 #include "memory/universe.inline.hpp"
36 #include "oops/access.inline.hpp"
37 #include "oops/cpCache.hpp"
38 #include "oops/objArrayOop.inline.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "prims/methodHandles.hpp"
41 #include "runtime/atomic.hpp"
42 #include "runtime/handles.inline.hpp"
43 #include "runtime/orderAccess.inline.hpp"
44 #include "utilities/macros.hpp"
45
46 // Implementation of ConstantPoolCacheEntry
47
48 void ConstantPoolCacheEntry::initialize_entry(int index) {
49 assert(0 < index && index < 0x10000, "sanity check");
50 _indices = index;
51 _f1 = NULL;
52 _f2 = _flags = 0;
53 assert(constant_pool_index() == index, "");
54 }
55
56 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) {
57 assert((_indices & (~cp_index_mask)) == 0, "sanity");
58 assert(_f1 == NULL, "sanity");
59 assert(_flags == 0, "sanity");
60 if (!f2_used) {
61 assert(_f2 == 0, "sanity");
62 }
63 }
64
65 void ConstantPoolCacheEntry::reinitialize(bool f2_used) {
66 _indices &= cp_index_mask;
67 _f1 = NULL;
68 _flags = 0;
69 if (!f2_used) {
70 _f2 = 0;
71 }
72 }
73
74 int ConstantPoolCacheEntry::make_flags(TosState state,
75 int option_bits,
76 int field_index_or_method_params) {
77 assert(state < number_of_states, "Invalid state in make_flags");
78 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
79 // Preserve existing flag bit values
80 // The low bits are a field offset, or else the method parameter size.
81 #ifdef ASSERT
82 TosState old_state = flag_state();
83 assert(old_state == (TosState)0 || old_state == state,
84 "inconsistent cpCache flags state");
85 #endif
86 return (_flags | f) ;
87 }
88
89 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
90 #ifdef ASSERT
91 // Read once.
92 volatile Bytecodes::Code c = bytecode_1();
93 assert(c == 0 || c == code || code == 0, "update must be consistent");
94 #endif
95 // Need to flush pending stores here before bytecode is written.
96 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift));
97 }
98
99 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
100 #ifdef ASSERT
101 // Read once.
102 volatile Bytecodes::Code c = bytecode_2();
103 assert(c == 0 || c == code || code == 0, "update must be consistent");
104 #endif
105 // Need to flush pending stores here before bytecode is written.
106 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift));
107 }
108
109 // Sets f1, ordering with previous writes.
110 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
111 assert(f1 != NULL, "");
112 OrderAccess::release_store(&_f1, f1);
113 }
114
115 void ConstantPoolCacheEntry::set_indy_resolution_failed() {
116 OrderAccess::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift));
117 }
118
119 // Note that concurrent update of both bytecodes can leave one of them
120 // reset to zero. This is harmless; the interpreter will simply re-resolve
121 // the damaged entry. More seriously, the memory synchronization is needed
122 // to flush other fields (f1, f2) completely to memory before the bytecodes
123 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
124 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
125 Bytecodes::Code put_code,
126 Klass* field_holder,
127 int field_index,
128 int field_offset,
129 TosState field_type,
130 bool is_final,
131 bool is_volatile,
132 Klass* root_klass) {
133 set_f1(field_holder);
134 set_f2(field_offset);
135 assert((field_index & field_index_mask) == field_index,
136 "field index does not fit in low flag bits");
137 set_field_flags(field_type,
138 ((is_volatile ? 1 : 0) << is_volatile_shift) |
139 ((is_final ? 1 : 0) << is_final_shift),
140 field_index);
141 set_bytecode_1(get_code);
142 set_bytecode_2(put_code);
143 NOT_PRODUCT(verify(tty));
144 }
145
146 void ConstantPoolCacheEntry::set_parameter_size(int value) {
147 // This routine is called only in corner cases where the CPCE is not yet initialized.
148 // See AbstractInterpreter::deopt_continue_after_entry.
149 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
150 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
151 // Setting the parameter size by itself is only safe if the
152 // current value of _flags is 0, otherwise another thread may have
153 // updated it and we don't want to overwrite that value. Don't
154 // bother trying to update it once it's nonzero but always make
155 // sure that the final parameter size agrees with what was passed.
156 if (_flags == 0) {
157 intx newflags = (value & parameter_size_mask);
158 Atomic::cmpxchg(newflags, &_flags, (intx)0);
159 }
160 guarantee(parameter_size() == value,
161 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
162 }
163
164 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
165 const methodHandle& method,
166 int vtable_index,
167 bool sender_is_interface) {
168 bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean
169 assert(method->interpreter_entry() != NULL, "should have been set at this point");
170 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
171
172 int byte_no = -1;
173 bool change_to_virtual = false;
174
175 switch (invoke_code) {
176 case Bytecodes::_invokeinterface:
177 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
178 // instruction somehow links to a non-interface method (in Object).
179 // In that case, the method has no itable index and must be invoked as a virtual.
180 // Set a flag to keep track of this corner case.
181 assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
182 change_to_virtual = true;
183
184 // ...and fall through as if we were handling invokevirtual:
185 case Bytecodes::_invokevirtual:
186 {
187 if (!is_vtable_call) {
188 assert(method->can_be_statically_bound(), "");
189 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
190 set_method_flags(as_TosState(method->result_type()),
191 ( 1 << is_vfinal_shift) |
192 ((method->is_final_method() ? 1 : 0) << is_final_shift) |
193 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
194 method()->size_of_parameters());
195 set_f2_as_vfinal_method(method());
196 } else {
197 assert(!method->can_be_statically_bound(), "");
198 assert(vtable_index >= 0, "valid index");
199 assert(!method->is_final_method(), "sanity");
200 set_method_flags(as_TosState(method->result_type()),
201 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
202 method()->size_of_parameters());
203 set_f2(vtable_index);
204 }
205 byte_no = 2;
206 break;
207 }
208
209 case Bytecodes::_invokespecial:
210 case Bytecodes::_invokestatic:
211 assert(!is_vtable_call, "");
212 // Note: Read and preserve the value of the is_vfinal flag on any
213 // invokevirtual bytecode shared with this constant pool cache entry.
214 // It is cheap and safe to consult is_vfinal() at all times.
215 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
216 set_method_flags(as_TosState(method->result_type()),
217 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
218 ((method->is_final_method() ? 1 : 0) << is_final_shift),
219 method()->size_of_parameters());
220 set_f1(method());
221 byte_no = 1;
222 break;
223 default:
224 ShouldNotReachHere();
225 break;
226 }
227
228 // Note: byte_no also appears in TemplateTable::resolve.
229 if (byte_no == 1) {
230 assert(invoke_code != Bytecodes::_invokevirtual &&
231 invoke_code != Bytecodes::_invokeinterface, "");
232 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
233 // has to be checked that it is a subclass of the current class every time this bytecode
234 // is executed.
235 if (invoke_code != Bytecodes::_invokespecial || !sender_is_interface ||
236 method->name() == vmSymbols::object_initializer_name()) {
237 set_bytecode_1(invoke_code);
238 }
239 } else if (byte_no == 2) {
240 if (change_to_virtual) {
241 assert(invoke_code == Bytecodes::_invokeinterface, "");
242 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
243 //
244 // Workaround for the case where we encounter an invokeinterface, but we
245 // should really have an _invokevirtual since the resolved method is a
246 // virtual method in java.lang.Object. This is a corner case in the spec
247 // but is presumably legal. javac does not generate this code.
248 //
249 // We set bytecode_1() to _invokeinterface, because that is the
250 // bytecode # used by the interpreter to see if it is resolved.
251 // We set bytecode_2() to _invokevirtual.
252 // See also interpreterRuntime.cpp. (8/25/2000)
253 // Only set resolved for the invokeinterface case if method is public.
254 // Otherwise, the method needs to be reresolved with caller for each
255 // interface call.
256 if (method->is_public()) set_bytecode_1(invoke_code);
257 } else {
258 assert(invoke_code == Bytecodes::_invokevirtual, "");
259 }
260 // set up for invokevirtual, even if linking for invokeinterface also:
261 set_bytecode_2(Bytecodes::_invokevirtual);
262 } else {
263 ShouldNotReachHere();
264 }
265 NOT_PRODUCT(verify(tty));
266 }
267
268 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
269 bool sender_is_interface) {
270 int index = Method::nonvirtual_vtable_index;
271 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
272 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
273 }
274
275 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
276 // either the method is a miranda or its holder should accept the given index
277 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
278 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
279 set_direct_or_vtable_call(invoke_code, method, index, false);
280 }
281
282 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
283 Klass* referenced_klass,
284 const methodHandle& method, int index) {
285 assert(method->method_holder()->verify_itable_index(index), "");
286 assert(invoke_code == Bytecodes::_invokeinterface, "");
287 InstanceKlass* interf = method->method_holder();
288 assert(interf->is_interface(), "must be an interface");
289 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
290 set_f1(referenced_klass);
291 set_f2((intx)method());
292 set_method_flags(as_TosState(method->result_type()),
293 0, // no option bits
294 method()->size_of_parameters());
295 set_bytecode_1(Bytecodes::_invokeinterface);
296 }
297
298
299 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
300 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
301 }
302
303 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
304 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
305 }
306
307 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
308 Bytecodes::Code invoke_code,
309 const CallInfo &call_info) {
310 // NOTE: This CPCE can be the subject of data races.
311 // There are three words to update: flags, refs[f2], f1 (in that order).
312 // Writers must store all other values before f1.
313 // Readers must test f1 first for non-null before reading other fields.
314 // Competing writers must acquire exclusive access via a lock.
315 // A losing writer waits on the lock until the winner writes f1 and leaves
316 // the lock, so that when the losing writer returns, he can use the linked
317 // cache entry.
318
319 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
320 // Use the resolved_references() lock for this cpCache entry.
321 // resolved_references are created for all classes with Invokedynamic, MethodHandle
322 // or MethodType constant pool cache entries.
323 assert(resolved_references() != NULL,
324 "a resolved_references array should have been created for this class");
325 ObjectLocker ol(resolved_references, Thread::current());
326 if (!is_f1_null()) {
327 return;
328 }
329
330 if (indy_resolution_failed()) {
331 // Before we got here, another thread got a LinkageError exception during
332 // resolution. Ignore our success and throw their exception.
333 ConstantPoolCache* cpCache = cpool->cache();
334 int index = -1;
335 for (int i = 0; i < cpCache->length(); i++) {
336 if (cpCache->entry_at(i) == this) {
337 index = i;
338 break;
339 }
340 }
341 guarantee(index >= 0, "Didn't find cpCache entry!");
342 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
343 ConstantPool::encode_invokedynamic_index(index));
344 Thread* THREAD = Thread::current();
345 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
346 return;
347 }
348
349 const methodHandle adapter = call_info.resolved_method();
350 const Handle appendix = call_info.resolved_appendix();
351 const Handle method_type = call_info.resolved_method_type();
352 const bool has_appendix = appendix.not_null();
353 const bool has_method_type = method_type.not_null();
354
355 // Write the flags.
356 set_method_flags(as_TosState(adapter->result_type()),
357 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
358 ((has_method_type ? 1 : 0) << has_method_type_shift) |
359 ( 1 << is_final_shift ),
360 adapter->size_of_parameters());
361
362 if (TraceInvokeDynamic) {
363 ttyLocker ttyl;
364 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ",
365 invoke_code,
366 p2i(appendix()), (has_appendix ? "" : " (unused)"),
367 p2i(method_type()), (has_method_type ? "" : " (unused)"),
368 p2i(adapter()));
369 adapter->print();
370 if (has_appendix) appendix()->print();
371 }
372
373 // Method handle invokes and invokedynamic sites use both cp cache words.
374 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
375 // In the general case, this could be the call site's MethodType,
376 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
377 // f1 contains the adapter method which manages the actual call.
378 // In the general case, this is a compiled LambdaForm.
379 // (The Java code is free to optimize these calls by binding other
380 // sorts of methods and appendices to call sites.)
381 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
382 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
383 // Even with the appendix, the method will never take more than 255 parameter slots.
384 //
385 // This means that given a call site like (List)mh.invoke("foo"),
386 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
387 // not '(Ljava/lang/String;)Ljava/util/List;'.
388 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
389 // This allows us to create fewer Methods, while keeping type safety.
390 //
391
392 // Store appendix, if any.
393 if (has_appendix) {
394 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
395 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
396 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
397 resolved_references->obj_at_put(appendix_index, appendix());
398 }
399
400 // Store MethodType, if any.
401 if (has_method_type) {
402 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
403 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
404 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
405 resolved_references->obj_at_put(method_type_index, method_type());
406 }
407
408 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
409
410 // The interpreter assembly code does not check byte_2,
411 // but it is used by is_resolved, method_if_resolved, etc.
412 set_bytecode_1(invoke_code);
413 NOT_PRODUCT(verify(tty));
414 if (TraceInvokeDynamic) {
415 ttyLocker ttyl;
416 this->print(tty, 0);
417 }
418 }
419
420 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
421 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
422
423 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
424 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
425 "No LinkageError exception");
426
427 // Use the resolved_references() lock for this cpCache entry.
428 // resolved_references are created for all classes with Invokedynamic, MethodHandle
429 // or MethodType constant pool cache entries.
430 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
431 assert(resolved_references() != NULL,
432 "a resolved_references array should have been created for this class");
433 ObjectLocker ol(resolved_references, THREAD);
434
435 // if f1 is not null or the indy_resolution_failed flag is set then another
436 // thread either succeeded in resolving the method or got a LinkageError
437 // exception, before this thread was able to record its failure. So, clear
438 // this thread's exception and return false so caller can use the earlier
439 // thread's result.
440 if (!is_f1_null() || indy_resolution_failed()) {
441 CLEAR_PENDING_EXCEPTION;
442 return false;
443 }
444
445 Symbol* error = PENDING_EXCEPTION->klass()->name();
446 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
447 assert(message != NULL, "Missing detail message");
448
449 SystemDictionary::add_resolution_error(cpool, index, error, message);
450 set_indy_resolution_failed();
451 return true;
452 }
453
454 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
455 // Decode the action of set_method and set_interface_call
456 Bytecodes::Code invoke_code = bytecode_1();
457 if (invoke_code != (Bytecodes::Code)0) {
458 Metadata* f1 = f1_ord();
459 if (f1 != NULL) {
460 switch (invoke_code) {
461 case Bytecodes::_invokeinterface:
462 assert(f1->is_klass(), "");
463 return klassItable::method_for_itable_index((Klass*)f1, f2_as_index());
464 case Bytecodes::_invokestatic:
465 case Bytecodes::_invokespecial:
466 assert(!has_appendix(), "");
467 case Bytecodes::_invokehandle:
468 case Bytecodes::_invokedynamic:
469 assert(f1->is_method(), "");
470 return (Method*)f1;
471 default:
472 break;
473 }
474 }
475 }
476 invoke_code = bytecode_2();
477 if (invoke_code != (Bytecodes::Code)0) {
478 switch (invoke_code) {
479 case Bytecodes::_invokevirtual:
480 if (is_vfinal()) {
481 // invokevirtual
482 Method* m = f2_as_vfinal_method();
483 assert(m->is_method(), "");
484 return m;
485 } else {
486 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
487 if (cpool->tag_at(holder_index).is_klass()) {
488 Klass* klass = cpool->resolved_klass_at(holder_index);
489 return klass->method_at_vtable(f2_as_index());
490 }
491 }
492 break;
493 default:
494 break;
495 }
496 }
497 return NULL;
498 }
499
500
501 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
502 if (!has_appendix())
503 return NULL;
504 const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset;
505 objArrayOop resolved_references = cpool->resolved_references();
506 return resolved_references->obj_at(ref_index);
507 }
508
509
510 oop ConstantPoolCacheEntry::method_type_if_resolved(const constantPoolHandle& cpool) {
511 if (!has_method_type())
512 return NULL;
513 const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset;
514 objArrayOop resolved_references = cpool->resolved_references();
515 return resolved_references->obj_at(ref_index);
516 }
517
518
519 #if INCLUDE_JVMTI
520
521 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
522 if (log_is_enabled(Info, redefine, class, update)) {
523 ResourceMark rm;
524 if (!(*trace_name_printed)) {
525 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
526 *trace_name_printed = true;
527 }
528 log_debug(redefine, class, update, constantpool)
529 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string());
530 }
531 }
532
533 // RedefineClasses() API support:
534 // If this ConstantPoolCacheEntry refers to old_method then update it
535 // to refer to new_method.
536 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
537 Method* new_method, bool * trace_name_printed) {
538
539 if (is_vfinal()) {
540 // virtual and final so _f2 contains method ptr instead of vtable index
541 if (f2_as_vfinal_method() == old_method) {
542 // match old_method so need an update
543 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
544 _f2 = (intptr_t)new_method;
545 log_adjust("vfinal", old_method, new_method, trace_name_printed);
546 }
547 return;
548 }
549
550 assert (_f1 != NULL, "should not call with uninteresting entry");
551
552 if (!(_f1->is_method())) {
553 // _f1 is a Klass* for an interface, _f2 is the method
554 if (f2_as_interface_method() == old_method) {
555 _f2 = (intptr_t)new_method;
556 log_adjust("interface", old_method, new_method, trace_name_printed);
557 }
558 } else if (_f1 == old_method) {
559 _f1 = new_method;
560 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
561 }
562 }
563
564 // a constant pool cache entry should never contain old or obsolete methods
565 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
566 Method* m = get_interesting_method_entry(NULL);
567 // return false if m refers to a non-deleted old or obsolete method
568 if (m != NULL) {
569 assert(m->is_valid() && m->is_method(), "m is a valid method");
570 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
571 } else {
572 return true;
573 }
574 }
575
576 Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) {
577 if (!is_method_entry()) {
578 // not a method entry so not interesting by default
579 return NULL;
580 }
581 Method* m = NULL;
582 if (is_vfinal()) {
583 // virtual and final so _f2 contains method ptr instead of vtable index
584 m = f2_as_vfinal_method();
585 } else if (is_f1_null()) {
586 // NULL _f1 means this is a virtual entry so also not interesting
587 return NULL;
588 } else {
589 if (!(_f1->is_method())) {
590 // _f1 is a Klass* for an interface
591 m = f2_as_interface_method();
592 } else {
593 m = f1_as_method();
594 }
595 }
596 assert(m != NULL && m->is_method(), "sanity check");
597 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
598 // robustness for above sanity checks or method is not in
599 // the interesting class
600 return NULL;
601 }
602 // the method is in the interesting class so the entry is interesting
603 return m;
604 }
605 #endif // INCLUDE_JVMTI
606
607 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
608 // print separator
609 if (index == 0) st->print_cr(" -------------");
610 // print entry
611 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
612 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
613 constant_pool_index());
614 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
615 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
616 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
617 st->print_cr(" -------------");
618 }
619
620 void ConstantPoolCacheEntry::verify(outputStream* st) const {
621 // not implemented yet
622 }
623
624 // Implementation of ConstantPoolCache
625
626 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
627 const intStack& index_map,
628 const intStack& invokedynamic_index_map,
629 const intStack& invokedynamic_map, TRAPS) {
630
631 const int length = index_map.length() + invokedynamic_index_map.length();
632 int size = ConstantPoolCache::size(length);
633
634 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
635 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
636 }
637
638 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
639 const intArray& invokedynamic_inverse_index_map,
640 const intArray& invokedynamic_references_map) {
641 for (int i = 0; i < inverse_index_map.length(); i++) {
642 ConstantPoolCacheEntry* e = entry_at(i);
643 int original_index = inverse_index_map.at(i);
644 e->initialize_entry(original_index);
645 assert(entry_at(i) == e, "sanity");
646 }
647
648 // Append invokedynamic entries at the end
649 int invokedynamic_offset = inverse_index_map.length();
650 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
651 int offset = i + invokedynamic_offset;
652 ConstantPoolCacheEntry* e = entry_at(offset);
653 int original_index = invokedynamic_inverse_index_map.at(i);
654 e->initialize_entry(original_index);
655 assert(entry_at(offset) == e, "sanity");
656 }
657
658 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
659 const int cpci = invokedynamic_references_map.at(ref);
660 if (cpci >= 0) {
661 #ifdef ASSERT
662 // invokedynamic and invokehandle have more entries; check if they
663 // all point to the same constant pool cache entry.
664 for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
665 const int cpci_next = invokedynamic_references_map.at(ref + entry);
666 assert(cpci == cpci_next, "%d == %d", cpci, cpci_next);
667 }
668 #endif
669 entry_at(cpci)->initialize_resolved_reference_index(ref);
670 ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries
671 }
672 }
673 }
674
675 void ConstantPoolCache::verify_just_initialized() {
676 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
677 }
678
679 void ConstantPoolCache::remove_unshareable_info() {
680 walk_entries_for_initialization(/*check_only = */ false);
681 }
682
683 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
684 assert(DumpSharedSpaces, "sanity");
685 // When dumping the archive, we want to clean up the ConstantPoolCache
686 // to remove any effect of linking due to the execution of Java code --
687 // each ConstantPoolCacheEntry will have the same contents as if
688 // ConstantPoolCache::initialize has just returned:
689 //
690 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
691 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
692 // - All other bits in the entries are cleared to zero.
693 ResourceMark rm;
694
695 InstanceKlass* ik = constant_pool()->pool_holder();
696 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
697 memset(f2_used, 0, sizeof(bool) * length());
698
699 // Find all the slots that we need to preserve f2
700 for (int i = 0; i < ik->methods()->length(); i++) {
701 Method* m = ik->methods()->at(i);
702 RawBytecodeStream bcs(m);
703 while (!bcs.is_last_bytecode()) {
704 Bytecodes::Code opcode = bcs.raw_next();
705 switch (opcode) {
706 case Bytecodes::_invokedynamic: {
707 int index = Bytes::get_native_u4(bcs.bcp() + 1);
708 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
709 f2_used[cp_cache_index] = 1;
710 }
711 break;
712 case Bytecodes::_invokehandle: {
713 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
714 f2_used[cp_cache_index] = 1;
715 }
716 break;
717 default:
718 break;
719 }
720 }
721 }
722
723 if (check_only) {
724 DEBUG_ONLY(
725 for (int i=0; i<length(); i++) {
726 entry_at(i)->verify_just_initialized(f2_used[i]);
727 })
728 } else {
729 for (int i=0; i<length(); i++) {
730 entry_at(i)->reinitialize(f2_used[i]);
731 }
732 }
733 }
734
735 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
736 assert(!is_shared(), "shared caches are not deallocated");
737 data->remove_handle(_resolved_references);
738 set_resolved_references(NULL);
739 MetadataFactory::free_array<u2>(data, _reference_map);
740 set_reference_map(NULL);
741 }
742
743 #if INCLUDE_CDS_JAVA_HEAP
744 oop ConstantPoolCache::archived_references() {
745 // Loading an archive root forces the oop to become strongly reachable.
746 // For example, if it is loaded during concurrent marking in a SATB
747 // collector, it will be enqueued to the SATB queue, effectively
748 // shading the previously white object gray.
749 return RootAccess<IN_ARCHIVE_ROOT>::oop_load(&_archived_references);
750 }
751
752 void ConstantPoolCache::set_archived_references(oop o) {
753 assert(DumpSharedSpaces, "called only during runtime");
754 RootAccess<IN_ARCHIVE_ROOT>::oop_store(&_archived_references, o);
755 }
756 #endif
757
758 #if INCLUDE_JVMTI
759 // RedefineClasses() API support:
760 // If any entry of this ConstantPoolCache points to any of
761 // old_methods, replace it with the corresponding new_method.
762 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
763 for (int i = 0; i < length(); i++) {
764 ConstantPoolCacheEntry* entry = entry_at(i);
765 Method* old_method = entry->get_interesting_method_entry(holder);
766 if (old_method == NULL || !old_method->is_old()) {
767 continue; // skip uninteresting entries
768 }
769 if (old_method->is_deleted()) {
770 // clean up entries with deleted methods
771 entry->initialize_entry(entry->constant_pool_index());
772 continue;
773 }
774 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
775
776 assert(new_method != NULL, "method_with_idnum() should not be NULL");
777 assert(old_method != new_method, "sanity check");
778
779 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
780 }
781 }
782
783 // the constant pool cache should never contain old or obsolete methods
784 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
785 for (int i = 1; i < length(); i++) {
786 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
787 !entry_at(i)->check_no_old_or_obsolete_entries()) {
788 return false;
789 }
790 }
791 return true;
792 }
793
794 void ConstantPoolCache::dump_cache() {
795 for (int i = 1; i < length(); i++) {
796 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
797 entry_at(i)->print(tty, i);
798 }
799 }
800 }
801 #endif // INCLUDE_JVMTI
802
803 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
804 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
805 it->push(&_constant_pool);
806 it->push(&_reference_map);
807 }
808
809 // Printing
810
811 void ConstantPoolCache::print_on(outputStream* st) const {
812 assert(is_constantPoolCache(), "obj must be constant pool cache");
813 st->print_cr("%s", internal_name());
814 // print constant pool cache entries
815 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
816 }
817
818 void ConstantPoolCache::print_value_on(outputStream* st) const {
819 assert(is_constantPoolCache(), "obj must be constant pool cache");
820 st->print("cache [%d]", length());
821 print_address_on(st);
822 st->print(" for ");
823 constant_pool()->print_value_on(st);
824 }
825
826
827 // Verification
828
829 void ConstantPoolCache::verify_on(outputStream* st) {
830 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
831 // print constant pool cache entries
832 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
833 }