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/cpCache.hpp"
37 #include "oops/objArrayOop.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "prims/methodHandles.hpp"
40 #include "runtime/atomic.hpp"
41 #include "runtime/handles.inline.hpp"
42 #include "runtime/orderAccess.inline.hpp"
43 #include "utilities/macros.hpp"
44
45 // Implementation of ConstantPoolCacheEntry
46
47 void ConstantPoolCacheEntry::initialize_entry(int index) {
48 assert(0 < index && index < 0x10000, "sanity check");
49 _indices = index;
50 _f1 = NULL;
51 _f2 = _flags = 0;
52 assert(constant_pool_index() == index, "");
53 }
54
55 void ConstantPoolCacheEntry::verify_just_initialized(bool f2_used) {
56 assert((_indices & (~cp_index_mask)) == 0, "sanity");
57 assert(_f1 == NULL, "sanity");
58 assert(_flags == 0, "sanity");
59 if (!f2_used) {
60 assert(_f2 == 0, "sanity");
61 }
62 }
63
64 void ConstantPoolCacheEntry::reinitialize(bool f2_used) {
65 _indices &= cp_index_mask;
66 _f1 = NULL;
67 _flags = 0;
68 if (!f2_used) {
69 _f2 = 0;
70 }
71 }
72
73 int ConstantPoolCacheEntry::make_flags(TosState state,
74 int option_bits,
75 int field_index_or_method_params) {
76 assert(state < number_of_states, "Invalid state in make_flags");
77 int f = ((int)state << tos_state_shift) | option_bits | field_index_or_method_params;
78 // Preserve existing flag bit values
79 // The low bits are a field offset, or else the method parameter size.
80 #ifdef ASSERT
81 TosState old_state = flag_state();
82 assert(old_state == (TosState)0 || old_state == state,
83 "inconsistent cpCache flags state");
84 #endif
85 return (_flags | f) ;
86 }
87
88 void ConstantPoolCacheEntry::set_bytecode_1(Bytecodes::Code code) {
89 #ifdef ASSERT
90 // Read once.
91 volatile Bytecodes::Code c = bytecode_1();
92 assert(c == 0 || c == code || code == 0, "update must be consistent");
93 #endif
94 // Need to flush pending stores here before bytecode is written.
95 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_1_shift));
96 }
97
98 void ConstantPoolCacheEntry::set_bytecode_2(Bytecodes::Code code) {
99 #ifdef ASSERT
100 // Read once.
101 volatile Bytecodes::Code c = bytecode_2();
102 assert(c == 0 || c == code || code == 0, "update must be consistent");
103 #endif
104 // Need to flush pending stores here before bytecode is written.
105 OrderAccess::release_store(&_indices, _indices | ((u_char)code << bytecode_2_shift));
106 }
107
108 // Sets f1, ordering with previous writes.
109 void ConstantPoolCacheEntry::release_set_f1(Metadata* f1) {
110 assert(f1 != NULL, "");
111 OrderAccess::release_store(&_f1, f1);
112 }
113
114 void ConstantPoolCacheEntry::set_indy_resolution_failed() {
115 OrderAccess::release_store(&_flags, _flags | (1 << indy_resolution_failed_shift));
116 }
117
118 // Note that concurrent update of both bytecodes can leave one of them
119 // reset to zero. This is harmless; the interpreter will simply re-resolve
120 // the damaged entry. More seriously, the memory synchronization is needed
121 // to flush other fields (f1, f2) completely to memory before the bytecodes
122 // are updated, lest other processors see a non-zero bytecode but zero f1/f2.
123 void ConstantPoolCacheEntry::set_field(Bytecodes::Code get_code,
124 Bytecodes::Code put_code,
125 Klass* field_holder,
126 int field_index,
127 int field_offset,
128 TosState field_type,
129 bool is_final,
130 bool is_volatile,
131 Klass* root_klass) {
132 set_f1(field_holder);
133 set_f2(field_offset);
134 assert((field_index & field_index_mask) == field_index,
135 "field index does not fit in low flag bits");
136 set_field_flags(field_type,
137 ((is_volatile ? 1 : 0) << is_volatile_shift) |
138 ((is_final ? 1 : 0) << is_final_shift),
139 field_index);
140 set_bytecode_1(get_code);
141 set_bytecode_2(put_code);
142 NOT_PRODUCT(verify(tty));
143 }
144
145 void ConstantPoolCacheEntry::set_parameter_size(int value) {
146 // This routine is called only in corner cases where the CPCE is not yet initialized.
147 // See AbstractInterpreter::deopt_continue_after_entry.
148 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
149 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
150 // Setting the parameter size by itself is only safe if the
151 // current value of _flags is 0, otherwise another thread may have
152 // updated it and we don't want to overwrite that value. Don't
153 // bother trying to update it once it's nonzero but always make
154 // sure that the final parameter size agrees with what was passed.
155 if (_flags == 0) {
156 intx newflags = (value & parameter_size_mask);
157 Atomic::cmpxchg(newflags, &_flags, (intx)0);
158 }
159 guarantee(parameter_size() == value,
160 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
161 }
162
163 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
164 const methodHandle& method,
165 int vtable_index,
166 bool sender_is_interface) {
167 bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean
168 assert(method->interpreter_entry() != NULL, "should have been set at this point");
169 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
170
171 int byte_no = -1;
172 bool change_to_virtual = false;
173
174 switch (invoke_code) {
175 case Bytecodes::_invokeinterface:
176 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
177 // instruction somehow links to a non-interface method (in Object).
178 // In that case, the method has no itable index and must be invoked as a virtual.
179 // Set a flag to keep track of this corner case.
180 assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
181 change_to_virtual = true;
182
183 // ...and fall through as if we were handling invokevirtual:
184 case Bytecodes::_invokevirtual:
185 {
186 if (!is_vtable_call) {
187 assert(method->can_be_statically_bound(), "");
188 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
189 set_method_flags(as_TosState(method->result_type()),
190 ( 1 << is_vfinal_shift) |
191 ((method->is_final_method() ? 1 : 0) << is_final_shift) |
192 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
193 method()->size_of_parameters());
194 set_f2_as_vfinal_method(method());
195 } else {
196 assert(!method->can_be_statically_bound(), "");
197 assert(vtable_index >= 0, "valid index");
198 assert(!method->is_final_method(), "sanity");
199 set_method_flags(as_TosState(method->result_type()),
200 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
201 method()->size_of_parameters());
202 set_f2(vtable_index);
203 }
204 byte_no = 2;
205 break;
206 }
207
208 case Bytecodes::_invokespecial:
209 case Bytecodes::_invokestatic:
210 assert(!is_vtable_call, "");
211 // Note: Read and preserve the value of the is_vfinal flag on any
212 // invokevirtual bytecode shared with this constant pool cache entry.
213 // It is cheap and safe to consult is_vfinal() at all times.
214 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
215 set_method_flags(as_TosState(method->result_type()),
216 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
217 ((method->is_final_method() ? 1 : 0) << is_final_shift),
218 method()->size_of_parameters());
219 set_f1(method());
220 byte_no = 1;
221 break;
222 default:
223 ShouldNotReachHere();
224 break;
225 }
226
227 // Note: byte_no also appears in TemplateTable::resolve.
228 if (byte_no == 1) {
229 assert(invoke_code != Bytecodes::_invokevirtual &&
230 invoke_code != Bytecodes::_invokeinterface, "");
231 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
232 // has to be checked that it is a subclass of the current class every time this bytecode
233 // is executed.
234 if (invoke_code != Bytecodes::_invokespecial || !sender_is_interface ||
235 method->name() == vmSymbols::object_initializer_name()) {
236 set_bytecode_1(invoke_code);
237 }
238 } else if (byte_no == 2) {
239 if (change_to_virtual) {
240 assert(invoke_code == Bytecodes::_invokeinterface, "");
241 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
242 //
243 // Workaround for the case where we encounter an invokeinterface, but we
244 // should really have an _invokevirtual since the resolved method is a
245 // virtual method in java.lang.Object. This is a corner case in the spec
246 // but is presumably legal. javac does not generate this code.
247 //
248 // We set bytecode_1() to _invokeinterface, because that is the
249 // bytecode # used by the interpreter to see if it is resolved.
250 // We set bytecode_2() to _invokevirtual.
251 // See also interpreterRuntime.cpp. (8/25/2000)
252 // Only set resolved for the invokeinterface case if method is public.
253 // Otherwise, the method needs to be reresolved with caller for each
254 // interface call.
255 if (method->is_public()) set_bytecode_1(invoke_code);
256 } else {
257 assert(invoke_code == Bytecodes::_invokevirtual, "");
258 }
259 // set up for invokevirtual, even if linking for invokeinterface also:
260 set_bytecode_2(Bytecodes::_invokevirtual);
261 } else {
262 ShouldNotReachHere();
263 }
264 NOT_PRODUCT(verify(tty));
265 }
266
267 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
268 bool sender_is_interface) {
269 int index = Method::nonvirtual_vtable_index;
270 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
271 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
272 }
273
274 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
275 // either the method is a miranda or its holder should accept the given index
276 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
277 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
278 set_direct_or_vtable_call(invoke_code, method, index, false);
279 }
280
281 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
282 assert(method->method_holder()->verify_itable_index(index), "");
283 assert(invoke_code == Bytecodes::_invokeinterface, "");
284 InstanceKlass* interf = method->method_holder();
285 assert(interf->is_interface(), "must be an interface");
286 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
287 set_f1(interf);
288 set_f2(index);
289 set_method_flags(as_TosState(method->result_type()),
290 0, // no option bits
291 method()->size_of_parameters());
292 set_bytecode_1(Bytecodes::_invokeinterface);
293 }
294
295
296 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
297 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
298 }
299
300 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
301 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
302 }
303
304 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
305 Bytecodes::Code invoke_code,
306 const CallInfo &call_info) {
307 // NOTE: This CPCE can be the subject of data races.
308 // There are three words to update: flags, refs[f2], f1 (in that order).
309 // Writers must store all other values before f1.
310 // Readers must test f1 first for non-null before reading other fields.
311 // Competing writers must acquire exclusive access via a lock.
312 // A losing writer waits on the lock until the winner writes f1 and leaves
313 // the lock, so that when the losing writer returns, he can use the linked
314 // cache entry.
315
316 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
317 // Use the resolved_references() lock for this cpCache entry.
318 // resolved_references are created for all classes with Invokedynamic, MethodHandle
319 // or MethodType constant pool cache entries.
320 assert(resolved_references() != NULL,
321 "a resolved_references array should have been created for this class");
322 ObjectLocker ol(resolved_references, Thread::current());
323 if (!is_f1_null()) {
324 return;
325 }
326
327 if (indy_resolution_failed()) {
328 // Before we got here, another thread got a LinkageError exception during
329 // resolution. Ignore our success and throw their exception.
330 ConstantPoolCache* cpCache = cpool->cache();
331 int index = -1;
332 for (int i = 0; i < cpCache->length(); i++) {
333 if (cpCache->entry_at(i) == this) {
334 index = i;
335 break;
336 }
337 }
338 guarantee(index >= 0, "Didn't find cpCache entry!");
339 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
340 ConstantPool::encode_invokedynamic_index(index));
341 Thread* THREAD = Thread::current();
342 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
343 return;
344 }
345
346 const methodHandle adapter = call_info.resolved_method();
347 const Handle appendix = call_info.resolved_appendix();
348 const Handle method_type = call_info.resolved_method_type();
349 const bool has_appendix = appendix.not_null();
350 const bool has_method_type = method_type.not_null();
351
352 // Write the flags.
353 set_method_flags(as_TosState(adapter->result_type()),
354 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
355 ((has_method_type ? 1 : 0) << has_method_type_shift) |
356 ( 1 << is_final_shift ),
357 adapter->size_of_parameters());
358
359 if (TraceInvokeDynamic) {
360 ttyLocker ttyl;
361 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ",
362 invoke_code,
363 p2i(appendix()), (has_appendix ? "" : " (unused)"),
364 p2i(method_type()), (has_method_type ? "" : " (unused)"),
365 p2i(adapter()));
366 adapter->print();
367 if (has_appendix) appendix()->print();
368 }
369
370 // Method handle invokes and invokedynamic sites use both cp cache words.
371 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
372 // In the general case, this could be the call site's MethodType,
373 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
374 // f1 contains the adapter method which manages the actual call.
375 // In the general case, this is a compiled LambdaForm.
376 // (The Java code is free to optimize these calls by binding other
377 // sorts of methods and appendices to call sites.)
378 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
379 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
380 // Even with the appendix, the method will never take more than 255 parameter slots.
381 //
382 // This means that given a call site like (List)mh.invoke("foo"),
383 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
384 // not '(Ljava/lang/String;)Ljava/util/List;'.
385 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
386 // This allows us to create fewer Methods, while keeping type safety.
387 //
388
389 // Store appendix, if any.
390 if (has_appendix) {
391 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
392 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
393 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
394 resolved_references->obj_at_put(appendix_index, appendix());
395 }
396
397 // Store MethodType, if any.
398 if (has_method_type) {
399 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
400 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
401 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
402 resolved_references->obj_at_put(method_type_index, method_type());
403 }
404
405 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
406
407 // The interpreter assembly code does not check byte_2,
408 // but it is used by is_resolved, method_if_resolved, etc.
409 set_bytecode_1(invoke_code);
410 NOT_PRODUCT(verify(tty));
411 if (TraceInvokeDynamic) {
412 ttyLocker ttyl;
413 this->print(tty, 0);
414 }
415 }
416
417 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
418 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
419
420 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
421 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
422 "No LinkageError exception");
423
424 // Use the resolved_references() lock for this cpCache entry.
425 // resolved_references are created for all classes with Invokedynamic, MethodHandle
426 // or MethodType constant pool cache entries.
427 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
428 assert(resolved_references() != NULL,
429 "a resolved_references array should have been created for this class");
430 ObjectLocker ol(resolved_references, THREAD);
431
432 // if f1 is not null or the indy_resolution_failed flag is set then another
433 // thread either succeeded in resolving the method or got a LinkageError
434 // exception, before this thread was able to record its failure. So, clear
435 // this thread's exception and return false so caller can use the earlier
436 // thread's result.
437 if (!is_f1_null() || indy_resolution_failed()) {
438 CLEAR_PENDING_EXCEPTION;
439 return false;
440 }
441
442 Symbol* error = PENDING_EXCEPTION->klass()->name();
443 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
444 assert(message != NULL, "Missing detail message");
445
446 SystemDictionary::add_resolution_error(cpool, index, error, message);
447 set_indy_resolution_failed();
448 return true;
449 }
450
451 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
452 // Decode the action of set_method and set_interface_call
453 Bytecodes::Code invoke_code = bytecode_1();
454 if (invoke_code != (Bytecodes::Code)0) {
455 Metadata* f1 = f1_ord();
456 if (f1 != NULL) {
457 switch (invoke_code) {
458 case Bytecodes::_invokeinterface:
459 assert(f1->is_klass(), "");
460 return klassItable::method_for_itable_index((Klass*)f1, f2_as_index());
461 case Bytecodes::_invokestatic:
462 case Bytecodes::_invokespecial:
463 assert(!has_appendix(), "");
464 case Bytecodes::_invokehandle:
465 case Bytecodes::_invokedynamic:
466 assert(f1->is_method(), "");
467 return (Method*)f1;
468 default:
469 break;
470 }
471 }
472 }
473 invoke_code = bytecode_2();
474 if (invoke_code != (Bytecodes::Code)0) {
475 switch (invoke_code) {
476 case Bytecodes::_invokevirtual:
477 if (is_vfinal()) {
478 // invokevirtual
479 Method* m = f2_as_vfinal_method();
480 assert(m->is_method(), "");
481 return m;
482 } else {
483 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
484 if (cpool->tag_at(holder_index).is_klass()) {
485 Klass* klass = cpool->resolved_klass_at(holder_index);
486 return klass->method_at_vtable(f2_as_index());
487 }
488 }
489 break;
490 default:
491 break;
492 }
493 }
494 return NULL;
495 }
496
497
498 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
499 if (!has_appendix())
500 return NULL;
501 const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset;
502 objArrayOop resolved_references = cpool->resolved_references();
503 return resolved_references->obj_at(ref_index);
504 }
505
506
507 oop ConstantPoolCacheEntry::method_type_if_resolved(const constantPoolHandle& cpool) {
508 if (!has_method_type())
509 return NULL;
510 const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset;
511 objArrayOop resolved_references = cpool->resolved_references();
512 return resolved_references->obj_at(ref_index);
513 }
514
515
516 #if INCLUDE_JVMTI
517 // RedefineClasses() API support:
518 // If this ConstantPoolCacheEntry refers to old_method then update it
519 // to refer to new_method.
520 bool ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
521 Method* new_method, bool * trace_name_printed) {
522
523 if (is_vfinal()) {
524 // virtual and final so _f2 contains method ptr instead of vtable index
525 if (f2_as_vfinal_method() == old_method) {
526 // match old_method so need an update
527 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
528 _f2 = (intptr_t)new_method;
529 if (log_is_enabled(Info, redefine, class, update)) {
530 ResourceMark rm;
531 if (!(*trace_name_printed)) {
532 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
533 *trace_name_printed = true;
534 }
535 log_debug(redefine, class, update, constantpool)
536 ("cpc vf-entry update: %s(%s)", new_method->name()->as_C_string(), new_method->signature()->as_C_string());
537 }
538 return true;
539 }
540
541 // f1() is not used with virtual entries so bail out
542 return false;
543 }
544
545 if (_f1 == NULL) {
546 // NULL f1() means this is a virtual entry so bail out
547 // We are assuming that the vtable index does not need change.
548 return false;
549 }
550
551 if (_f1 == old_method) {
552 _f1 = new_method;
553 if (log_is_enabled(Info, redefine, class, update)) {
554 ResourceMark rm;
555 if (!(*trace_name_printed)) {
556 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
557 *trace_name_printed = true;
558 }
559 log_debug(redefine, class, update, constantpool)
560 ("cpc entry update: %s(%s)", new_method->name()->as_C_string(), new_method->signature()->as_C_string());
561 }
562 return true;
563 }
564
565 return false;
566 }
567
568 // a constant pool cache entry should never contain old or obsolete methods
569 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
570 if (is_vfinal()) {
571 // virtual and final so _f2 contains method ptr instead of vtable index
572 Metadata* f2 = (Metadata*)_f2;
573 // Return false if _f2 refers to an old or an obsolete method.
574 // _f2 == NULL || !_f2->is_method() are just as unexpected here.
575 return (f2 != NULL NOT_PRODUCT(&& f2->is_valid()) && f2->is_method() &&
576 !((Method*)f2)->is_old() && !((Method*)f2)->is_obsolete());
577 } else if (_f1 == NULL ||
578 (NOT_PRODUCT(_f1->is_valid() &&) !_f1->is_method())) {
579 // _f1 == NULL || !_f1->is_method() are OK here
580 return true;
581 }
582 // return false if _f1 refers to a non-deleted old or obsolete method
583 return (NOT_PRODUCT(_f1->is_valid() &&) _f1->is_method() &&
584 (f1_as_method()->is_deleted() ||
585 (!f1_as_method()->is_old() && !f1_as_method()->is_obsolete())));
586 }
587
588 Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) {
589 if (!is_method_entry()) {
590 // not a method entry so not interesting by default
591 return NULL;
592 }
593 Method* m = NULL;
594 if (is_vfinal()) {
595 // virtual and final so _f2 contains method ptr instead of vtable index
596 m = f2_as_vfinal_method();
597 } else if (is_f1_null()) {
598 // NULL _f1 means this is a virtual entry so also not interesting
599 return NULL;
600 } else {
601 if (!(_f1->is_method())) {
602 // _f1 can also contain a Klass* for an interface
603 return NULL;
604 }
605 m = f1_as_method();
606 }
607 assert(m != NULL && m->is_method(), "sanity check");
608 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
609 // robustness for above sanity checks or method is not in
610 // the interesting class
611 return NULL;
612 }
613 // the method is in the interesting class so the entry is interesting
614 return m;
615 }
616 #endif // INCLUDE_JVMTI
617
618 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
619 // print separator
620 if (index == 0) st->print_cr(" -------------");
621 // print entry
622 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
623 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
624 constant_pool_index());
625 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
626 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
627 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
628 st->print_cr(" -------------");
629 }
630
631 void ConstantPoolCacheEntry::verify(outputStream* st) const {
632 // not implemented yet
633 }
634
635 // Implementation of ConstantPoolCache
636
637 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
638 const intStack& index_map,
639 const intStack& invokedynamic_index_map,
640 const intStack& invokedynamic_map, TRAPS) {
641
642 const int length = index_map.length() + invokedynamic_index_map.length();
643 int size = ConstantPoolCache::size(length);
644
645 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
646 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
647 }
648
649 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
650 const intArray& invokedynamic_inverse_index_map,
651 const intArray& invokedynamic_references_map) {
652 for (int i = 0; i < inverse_index_map.length(); i++) {
653 ConstantPoolCacheEntry* e = entry_at(i);
654 int original_index = inverse_index_map.at(i);
655 e->initialize_entry(original_index);
656 assert(entry_at(i) == e, "sanity");
657 }
658
659 // Append invokedynamic entries at the end
660 int invokedynamic_offset = inverse_index_map.length();
661 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
662 int offset = i + invokedynamic_offset;
663 ConstantPoolCacheEntry* e = entry_at(offset);
664 int original_index = invokedynamic_inverse_index_map.at(i);
665 e->initialize_entry(original_index);
666 assert(entry_at(offset) == e, "sanity");
667 }
668
669 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
670 const int cpci = invokedynamic_references_map.at(ref);
671 if (cpci >= 0) {
672 #ifdef ASSERT
673 // invokedynamic and invokehandle have more entries; check if they
674 // all point to the same constant pool cache entry.
675 for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
676 const int cpci_next = invokedynamic_references_map.at(ref + entry);
677 assert(cpci == cpci_next, "%d == %d", cpci, cpci_next);
678 }
679 #endif
680 entry_at(cpci)->initialize_resolved_reference_index(ref);
681 ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries
682 }
683 }
684 }
685
686 void ConstantPoolCache::verify_just_initialized() {
687 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
688 }
689
690 void ConstantPoolCache::remove_unshareable_info() {
691 walk_entries_for_initialization(/*check_only = */ false);
692 }
693
694 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
695 assert(DumpSharedSpaces, "sanity");
696 // When dumping the archive, we want to clean up the ConstantPoolCache
697 // to remove any effect of linking due to the execution of Java code --
698 // each ConstantPoolCacheEntry will have the same contents as if
699 // ConstantPoolCache::initialize has just returned:
700 //
701 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
702 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
703 // - All other bits in the entries are cleared to zero.
704 ResourceMark rm;
705
706 InstanceKlass* ik = constant_pool()->pool_holder();
707 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
708 memset(f2_used, 0, sizeof(bool) * length());
709
710 // Find all the slots that we need to preserve f2
711 for (int i = 0; i < ik->methods()->length(); i++) {
712 Method* m = ik->methods()->at(i);
713 RawBytecodeStream bcs(m);
714 while (!bcs.is_last_bytecode()) {
715 Bytecodes::Code opcode = bcs.raw_next();
716 switch (opcode) {
717 case Bytecodes::_invokedynamic: {
718 int index = Bytes::get_native_u4(bcs.bcp() + 1);
719 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
720 f2_used[cp_cache_index] = 1;
721 }
722 break;
723 case Bytecodes::_invokehandle: {
724 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
725 f2_used[cp_cache_index] = 1;
726 }
727 break;
728 default:
729 break;
730 }
731 }
732 }
733
734 if (check_only) {
735 DEBUG_ONLY(
736 for (int i=0; i<length(); i++) {
737 entry_at(i)->verify_just_initialized(f2_used[i]);
738 })
739 } else {
740 for (int i=0; i<length(); i++) {
741 entry_at(i)->reinitialize(f2_used[i]);
742 }
743 }
744 }
745
746 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
747 assert(!is_shared(), "shared caches are not deallocated");
748 data->remove_handle(_resolved_references);
749 set_resolved_references(NULL);
750 MetadataFactory::free_array<u2>(data, _reference_map);
751 set_reference_map(NULL);
752 }
753
754 #if INCLUDE_CDS_JAVA_HEAP
755 oop ConstantPoolCache::archived_references() {
756 assert(UseSharedSpaces, "UseSharedSpaces expected.");
757 return oopDesc::decode_heap_oop(_archived_references);
758 }
759
760 void ConstantPoolCache::set_archived_references(oop o) {
761 assert(DumpSharedSpaces, "called only during runtime");
762 _archived_references = oopDesc::encode_heap_oop(o);
763 }
764 #endif
765
766 #if INCLUDE_JVMTI
767 // RedefineClasses() API support:
768 // If any entry of this ConstantPoolCache points to any of
769 // old_methods, replace it with the corresponding new_method.
770 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
771 for (int i = 0; i < length(); i++) {
772 ConstantPoolCacheEntry* entry = entry_at(i);
773 Method* old_method = entry->get_interesting_method_entry(holder);
774 if (old_method == NULL || !old_method->is_old()) {
775 continue; // skip uninteresting entries
776 }
777 if (old_method->is_deleted()) {
778 // clean up entries with deleted methods
779 entry->initialize_entry(entry->constant_pool_index());
780 continue;
781 }
782 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
783
784 assert(new_method != NULL, "method_with_idnum() should not be NULL");
785 assert(old_method != new_method, "sanity check");
786
787 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
788 }
789 }
790
791 // the constant pool cache should never contain old or obsolete methods
792 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
793 for (int i = 1; i < length(); i++) {
794 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
795 !entry_at(i)->check_no_old_or_obsolete_entries()) {
796 return false;
797 }
798 }
799 return true;
800 }
801
802 void ConstantPoolCache::dump_cache() {
803 for (int i = 1; i < length(); i++) {
804 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
805 entry_at(i)->print(tty, i);
806 }
807 }
808 }
809 #endif // INCLUDE_JVMTI
810
811 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
812 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
813 it->push(&_constant_pool);
814 it->push(&_reference_map);
815 }
816
817 // Printing
818
819 void ConstantPoolCache::print_on(outputStream* st) const {
820 assert(is_constantPoolCache(), "obj must be constant pool cache");
821 st->print_cr("%s", internal_name());
822 // print constant pool cache entries
823 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
824 }
825
826 void ConstantPoolCache::print_value_on(outputStream* st) const {
827 assert(is_constantPoolCache(), "obj must be constant pool cache");
828 st->print("cache [%d]", length());
829 print_address_on(st);
830 st->print(" for ");
831 constant_pool()->print_value_on(st);
832 }
833
834
835 // Verification
836
837 void ConstantPoolCache::verify_on(outputStream* st) {
838 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
839 // print constant pool cache entries
840 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
841 }