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 bool is_flatten,
133 bool is_flattenable,
134 Klass* root_klass) {
135 set_f1(field_holder);
136 set_f2(field_offset);
137 assert((field_index & field_index_mask) == field_index,
138 "field index does not fit in low flag bits");
139 set_field_flags(field_type,
140 ((is_volatile ? 1 : 0) << is_volatile_shift) |
141 ((is_final ? 1 : 0) << is_final_shift) |
142 ((is_flatten ? 1 : 0) << is_flatten_field) |
143 ((is_flattenable ? 1 : 0) << is_flattenable_field),
144 field_index);
145 set_bytecode_1(get_code);
146 set_bytecode_2(put_code);
147 NOT_PRODUCT(verify(tty));
148 }
149
150 void ConstantPoolCacheEntry::set_parameter_size(int value) {
151 // This routine is called only in corner cases where the CPCE is not yet initialized.
152 // See AbstractInterpreter::deopt_continue_after_entry.
153 assert(_flags == 0 || parameter_size() == 0 || parameter_size() == value,
154 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
155 // Setting the parameter size by itself is only safe if the
156 // current value of _flags is 0, otherwise another thread may have
157 // updated it and we don't want to overwrite that value. Don't
158 // bother trying to update it once it's nonzero but always make
159 // sure that the final parameter size agrees with what was passed.
160 if (_flags == 0) {
161 intx newflags = (value & parameter_size_mask);
162 Atomic::cmpxchg(newflags, &_flags, (intx)0);
163 }
164 guarantee(parameter_size() == value,
165 "size must not change: parameter_size=%d, value=%d", parameter_size(), value);
166 }
167
168 void ConstantPoolCacheEntry::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
169 const methodHandle& method,
170 int vtable_index,
171 bool sender_is_interface) {
172 bool is_vtable_call = (vtable_index >= 0); // FIXME: split this method on this boolean
173 assert(method->interpreter_entry() != NULL, "should have been set at this point");
174 assert(!method->is_obsolete(), "attempt to write obsolete method to cpCache");
175
176 int byte_no = -1;
177 bool change_to_virtual = false;
178
179 switch (invoke_code) {
180 case Bytecodes::_invokeinterface:
181 // We get here from InterpreterRuntime::resolve_invoke when an invokeinterface
182 // instruction somehow links to a non-interface method (in Object).
183 // In that case, the method has no itable index and must be invoked as a virtual.
184 // Set a flag to keep track of this corner case.
185 assert(method->is_public(), "Calling non-public method in Object with invokeinterface");
186 change_to_virtual = true;
187
188 // ...and fall through as if we were handling invokevirtual:
189 case Bytecodes::_invokevirtual:
190 {
191 if (!is_vtable_call) {
192 assert(method->can_be_statically_bound(), "");
193 // set_f2_as_vfinal_method checks if is_vfinal flag is true.
194 set_method_flags(as_TosState(method->result_type()),
195 ( 1 << is_vfinal_shift) |
196 ((method->is_final_method() ? 1 : 0) << is_final_shift) |
197 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
198 method()->size_of_parameters());
199 set_f2_as_vfinal_method(method());
200 } else {
201 assert(!method->can_be_statically_bound(), "");
202 assert(vtable_index >= 0, "valid index");
203 assert(!method->is_final_method(), "sanity");
204 set_method_flags(as_TosState(method->result_type()),
205 ((change_to_virtual ? 1 : 0) << is_forced_virtual_shift),
206 method()->size_of_parameters());
207 set_f2(vtable_index);
208 }
209 byte_no = 2;
210 break;
211 }
212
213 case Bytecodes::_invokespecial:
214 case Bytecodes::_invokestatic:
215 assert(!is_vtable_call, "");
216 // Note: Read and preserve the value of the is_vfinal flag on any
217 // invokevirtual bytecode shared with this constant pool cache entry.
218 // It is cheap and safe to consult is_vfinal() at all times.
219 // Once is_vfinal is set, it must stay that way, lest we get a dangling oop.
220 set_method_flags(as_TosState(method->result_type()),
221 ((is_vfinal() ? 1 : 0) << is_vfinal_shift) |
222 ((method->is_final_method() ? 1 : 0) << is_final_shift),
223 method()->size_of_parameters());
224 set_f1(method());
225 byte_no = 1;
226 break;
227 default:
228 ShouldNotReachHere();
229 break;
230 }
231
232 // Note: byte_no also appears in TemplateTable::resolve.
233 if (byte_no == 1) {
234 assert(invoke_code != Bytecodes::_invokevirtual &&
235 invoke_code != Bytecodes::_invokeinterface, "");
236 // Don't mark invokespecial to method as resolved if sender is an interface. The receiver
237 // has to be checked that it is a subclass of the current class every time this bytecode
238 // is executed.
239 if (invoke_code != Bytecodes::_invokespecial || !sender_is_interface ||
240 method->name() == vmSymbols::object_initializer_name()) {
241 set_bytecode_1(invoke_code);
242 }
243 } else if (byte_no == 2) {
244 if (change_to_virtual) {
245 assert(invoke_code == Bytecodes::_invokeinterface, "");
246 // NOTE: THIS IS A HACK - BE VERY CAREFUL!!!
247 //
248 // Workaround for the case where we encounter an invokeinterface, but we
249 // should really have an _invokevirtual since the resolved method is a
250 // virtual method in java.lang.Object. This is a corner case in the spec
251 // but is presumably legal. javac does not generate this code.
252 //
253 // We set bytecode_1() to _invokeinterface, because that is the
254 // bytecode # used by the interpreter to see if it is resolved.
255 // We set bytecode_2() to _invokevirtual.
256 // See also interpreterRuntime.cpp. (8/25/2000)
257 // Only set resolved for the invokeinterface case if method is public.
258 // Otherwise, the method needs to be reresolved with caller for each
259 // interface call.
260 if (method->is_public()) set_bytecode_1(invoke_code);
261 invoke_code = Bytecodes::_invokevirtual;
262 } else {
263 assert(invoke_code == Bytecodes::_invokevirtual, "");
264 }
265 // set up for invokevirtual, even if linking for invokeinterface also:
266 set_bytecode_2(invoke_code);
267 } else {
268 ShouldNotReachHere();
269 }
270 NOT_PRODUCT(verify(tty));
271 }
272
273 void ConstantPoolCacheEntry::set_direct_call(Bytecodes::Code invoke_code, const methodHandle& method,
274 bool sender_is_interface) {
275 int index = Method::nonvirtual_vtable_index;
276 // index < 0; FIXME: inline and customize set_direct_or_vtable_call
277 set_direct_or_vtable_call(invoke_code, method, index, sender_is_interface);
278 }
279
280 void ConstantPoolCacheEntry::set_vtable_call(Bytecodes::Code invoke_code, const methodHandle& method, int index) {
281 // either the method is a miranda or its holder should accept the given index
282 assert(method->method_holder()->is_interface() || method->method_holder()->verify_vtable_index(index), "");
283 // index >= 0; FIXME: inline and customize set_direct_or_vtable_call
284 set_direct_or_vtable_call(invoke_code, method, index, false);
285 }
286
287 void ConstantPoolCacheEntry::set_itable_call(Bytecodes::Code invoke_code,
288 Klass* referenced_klass,
289 const methodHandle& method, int index) {
290 assert(method->method_holder()->verify_itable_index(index), "");
291 assert(invoke_code == Bytecodes::_invokeinterface, "");
292 InstanceKlass* interf = method->method_holder();
293 assert(interf->is_interface(), "must be an interface");
294 assert(!method->is_final_method(), "interfaces do not have final methods; cannot link to one here");
295 set_f1(referenced_klass);
296 set_f2((intx)method());
297 set_method_flags(as_TosState(method->result_type()),
298 0, // no option bits
299 method()->size_of_parameters());
300 set_bytecode_1(Bytecodes::_invokeinterface);
301 }
302
303
304 void ConstantPoolCacheEntry::set_method_handle(const constantPoolHandle& cpool, const CallInfo &call_info) {
305 set_method_handle_common(cpool, Bytecodes::_invokehandle, call_info);
306 }
307
308 void ConstantPoolCacheEntry::set_dynamic_call(const constantPoolHandle& cpool, const CallInfo &call_info) {
309 set_method_handle_common(cpool, Bytecodes::_invokedynamic, call_info);
310 }
311
312 void ConstantPoolCacheEntry::set_method_handle_common(const constantPoolHandle& cpool,
313 Bytecodes::Code invoke_code,
314 const CallInfo &call_info) {
315 // NOTE: This CPCE can be the subject of data races.
316 // There are three words to update: flags, refs[f2], f1 (in that order).
317 // Writers must store all other values before f1.
318 // Readers must test f1 first for non-null before reading other fields.
319 // Competing writers must acquire exclusive access via a lock.
320 // A losing writer waits on the lock until the winner writes f1 and leaves
321 // the lock, so that when the losing writer returns, he can use the linked
322 // cache entry.
323
324 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
325 // Use the resolved_references() lock for this cpCache entry.
326 // resolved_references are created for all classes with Invokedynamic, MethodHandle
327 // or MethodType constant pool cache entries.
328 assert(resolved_references() != NULL,
329 "a resolved_references array should have been created for this class");
330 ObjectLocker ol(resolved_references, Thread::current());
331 if (!is_f1_null()) {
332 return;
333 }
334
335 if (indy_resolution_failed()) {
336 // Before we got here, another thread got a LinkageError exception during
337 // resolution. Ignore our success and throw their exception.
338 ConstantPoolCache* cpCache = cpool->cache();
339 int index = -1;
340 for (int i = 0; i < cpCache->length(); i++) {
341 if (cpCache->entry_at(i) == this) {
342 index = i;
343 break;
344 }
345 }
346 guarantee(index >= 0, "Didn't find cpCache entry!");
347 int encoded_index = ResolutionErrorTable::encode_cpcache_index(
348 ConstantPool::encode_invokedynamic_index(index));
349 Thread* THREAD = Thread::current();
350 ConstantPool::throw_resolution_error(cpool, encoded_index, THREAD);
351 return;
352 }
353
354 const methodHandle adapter = call_info.resolved_method();
355 const Handle appendix = call_info.resolved_appendix();
356 const Handle method_type = call_info.resolved_method_type();
357 const bool has_appendix = appendix.not_null();
358 const bool has_method_type = method_type.not_null();
359
360 // Write the flags.
361 set_method_flags(as_TosState(adapter->result_type()),
362 ((has_appendix ? 1 : 0) << has_appendix_shift ) |
363 ((has_method_type ? 1 : 0) << has_method_type_shift) |
364 ( 1 << is_final_shift ),
365 adapter->size_of_parameters());
366
367 if (TraceInvokeDynamic) {
368 ttyLocker ttyl;
369 tty->print_cr("set_method_handle bc=%d appendix=" PTR_FORMAT "%s method_type=" PTR_FORMAT "%s method=" PTR_FORMAT " ",
370 invoke_code,
371 p2i(appendix()), (has_appendix ? "" : " (unused)"),
372 p2i(method_type()), (has_method_type ? "" : " (unused)"),
373 p2i(adapter()));
374 adapter->print();
375 if (has_appendix) appendix()->print();
376 }
377
378 // Method handle invokes and invokedynamic sites use both cp cache words.
379 // refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
380 // In the general case, this could be the call site's MethodType,
381 // for use with java.lang.Invokers.checkExactType, or else a CallSite object.
382 // f1 contains the adapter method which manages the actual call.
383 // In the general case, this is a compiled LambdaForm.
384 // (The Java code is free to optimize these calls by binding other
385 // sorts of methods and appendices to call sites.)
386 // JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
387 // The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
388 // Even with the appendix, the method will never take more than 255 parameter slots.
389 //
390 // This means that given a call site like (List)mh.invoke("foo"),
391 // the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
392 // not '(Ljava/lang/String;)Ljava/util/List;'.
393 // The fact that String and List are involved is encoded in the MethodType in refs[f2].
394 // This allows us to create fewer Methods, while keeping type safety.
395 //
396
397 // Store appendix, if any.
398 if (has_appendix) {
399 const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
400 assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
401 assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
402 resolved_references->obj_at_put(appendix_index, appendix());
403 }
404
405 // Store MethodType, if any.
406 if (has_method_type) {
407 const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
408 assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
409 assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
410 resolved_references->obj_at_put(method_type_index, method_type());
411 }
412
413 release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
414
415 // The interpreter assembly code does not check byte_2,
416 // but it is used by is_resolved, method_if_resolved, etc.
417 set_bytecode_1(invoke_code);
418 NOT_PRODUCT(verify(tty));
419 if (TraceInvokeDynamic) {
420 ttyLocker ttyl;
421 this->print(tty, 0);
422 }
423 }
424
425 bool ConstantPoolCacheEntry::save_and_throw_indy_exc(
426 const constantPoolHandle& cpool, int cpool_index, int index, constantTag tag, TRAPS) {
427
428 assert(HAS_PENDING_EXCEPTION, "No exception got thrown!");
429 assert(PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass()),
430 "No LinkageError exception");
431
432 // Use the resolved_references() lock for this cpCache entry.
433 // resolved_references are created for all classes with Invokedynamic, MethodHandle
434 // or MethodType constant pool cache entries.
435 objArrayHandle resolved_references(Thread::current(), cpool->resolved_references());
436 assert(resolved_references() != NULL,
437 "a resolved_references array should have been created for this class");
438 ObjectLocker ol(resolved_references, THREAD);
439
440 // if f1 is not null or the indy_resolution_failed flag is set then another
441 // thread either succeeded in resolving the method or got a LinkageError
442 // exception, before this thread was able to record its failure. So, clear
443 // this thread's exception and return false so caller can use the earlier
444 // thread's result.
445 if (!is_f1_null() || indy_resolution_failed()) {
446 CLEAR_PENDING_EXCEPTION;
447 return false;
448 }
449
450 Symbol* error = PENDING_EXCEPTION->klass()->name();
451 Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
452 assert(message != NULL, "Missing detail message");
453
454 SystemDictionary::add_resolution_error(cpool, index, error, message);
455 set_indy_resolution_failed();
456 return true;
457 }
458
459 Method* ConstantPoolCacheEntry::method_if_resolved(const constantPoolHandle& cpool) {
460 // Decode the action of set_method and set_interface_call
461 Bytecodes::Code invoke_code = bytecode_1();
462 if (invoke_code != (Bytecodes::Code)0) {
463 Metadata* f1 = f1_ord();
464 if (f1 != NULL) {
465 switch (invoke_code) {
466 case Bytecodes::_invokeinterface:
467 assert(f1->is_klass(), "");
468 return klassItable::method_for_itable_index((Klass*)f1, f2_as_index());
469 case Bytecodes::_invokestatic:
470 case Bytecodes::_invokespecial:
471 assert(!has_appendix(), "");
472 case Bytecodes::_invokehandle:
473 case Bytecodes::_invokedynamic:
474 assert(f1->is_method(), "");
475 return (Method*)f1;
476 default:
477 break;
478 }
479 }
480 }
481 invoke_code = bytecode_2();
482 if (invoke_code != (Bytecodes::Code)0) {
483 switch (invoke_code) {
484 case Bytecodes::_invokevirtual:
485 if (is_vfinal()) {
486 // invokevirtual
487 Method* m = f2_as_vfinal_method();
488 assert(m->is_method(), "");
489 return m;
490 } else {
491 int holder_index = cpool->uncached_klass_ref_index_at(constant_pool_index());
492 if (cpool->tag_at(holder_index).is_klass()) {
493 Klass* klass = cpool->resolved_klass_at(holder_index);
494 return klass->method_at_vtable(f2_as_index());
495 }
496 }
497 break;
498 default:
499 break;
500 }
501 }
502 return NULL;
503 }
504
505
506 oop ConstantPoolCacheEntry::appendix_if_resolved(const constantPoolHandle& cpool) {
507 if (!has_appendix())
508 return NULL;
509 const int ref_index = f2_as_index() + _indy_resolved_references_appendix_offset;
510 objArrayOop resolved_references = cpool->resolved_references();
511 return resolved_references->obj_at(ref_index);
512 }
513
514
515 oop ConstantPoolCacheEntry::method_type_if_resolved(const constantPoolHandle& cpool) {
516 if (!has_method_type())
517 return NULL;
518 const int ref_index = f2_as_index() + _indy_resolved_references_method_type_offset;
519 objArrayOop resolved_references = cpool->resolved_references();
520 return resolved_references->obj_at(ref_index);
521 }
522
523
524 #if INCLUDE_JVMTI
525
526 void log_adjust(const char* entry_type, Method* old_method, Method* new_method, bool* trace_name_printed) {
527 if (log_is_enabled(Info, redefine, class, update)) {
528 ResourceMark rm;
529 if (!(*trace_name_printed)) {
530 log_info(redefine, class, update)("adjust: name=%s", old_method->method_holder()->external_name());
531 *trace_name_printed = true;
532 }
533 log_debug(redefine, class, update, constantpool)
534 ("cpc %s entry update: %s(%s)", entry_type, new_method->name()->as_C_string(), new_method->signature()->as_C_string());
535 }
536 }
537
538 // RedefineClasses() API support:
539 // If this ConstantPoolCacheEntry refers to old_method then update it
540 // to refer to new_method.
541 void ConstantPoolCacheEntry::adjust_method_entry(Method* old_method,
542 Method* new_method, bool * trace_name_printed) {
543
544 if (is_vfinal()) {
545 // virtual and final so _f2 contains method ptr instead of vtable index
546 if (f2_as_vfinal_method() == old_method) {
547 // match old_method so need an update
548 // NOTE: can't use set_f2_as_vfinal_method as it asserts on different values
549 _f2 = (intptr_t)new_method;
550 log_adjust("vfinal", old_method, new_method, trace_name_printed);
551 }
552 return;
553 }
554
555 assert (_f1 != NULL, "should not call with uninteresting entry");
556
557 if (!(_f1->is_method())) {
558 // _f1 is a Klass* for an interface, _f2 is the method
559 if (f2_as_interface_method() == old_method) {
560 _f2 = (intptr_t)new_method;
561 log_adjust("interface", old_method, new_method, trace_name_printed);
562 }
563 } else if (_f1 == old_method) {
564 _f1 = new_method;
565 log_adjust("special, static or dynamic", old_method, new_method, trace_name_printed);
566 }
567 }
568
569 // a constant pool cache entry should never contain old or obsolete methods
570 bool ConstantPoolCacheEntry::check_no_old_or_obsolete_entries() {
571 Method* m = get_interesting_method_entry(NULL);
572 // return false if m refers to a non-deleted old or obsolete method
573 if (m != NULL) {
574 assert(m->is_valid() && m->is_method(), "m is a valid method");
575 return !m->is_old() && !m->is_obsolete(); // old is always set for old and obsolete
576 } else {
577 return true;
578 }
579 }
580
581 Method* ConstantPoolCacheEntry::get_interesting_method_entry(Klass* k) {
582 if (!is_method_entry()) {
583 // not a method entry so not interesting by default
584 return NULL;
585 }
586 Method* m = NULL;
587 if (is_vfinal()) {
588 // virtual and final so _f2 contains method ptr instead of vtable index
589 m = f2_as_vfinal_method();
590 } else if (is_f1_null()) {
591 // NULL _f1 means this is a virtual entry so also not interesting
592 return NULL;
593 } else {
594 if (!(_f1->is_method())) {
595 // _f1 is a Klass* for an interface
596 m = f2_as_interface_method();
597 } else {
598 m = f1_as_method();
599 }
600 }
601 assert(m != NULL && m->is_method(), "sanity check");
602 if (m == NULL || !m->is_method() || (k != NULL && m->method_holder() != k)) {
603 // robustness for above sanity checks or method is not in
604 // the interesting class
605 return NULL;
606 }
607 // the method is in the interesting class so the entry is interesting
608 return m;
609 }
610 #endif // INCLUDE_JVMTI
611
612 void ConstantPoolCacheEntry::print(outputStream* st, int index) const {
613 // print separator
614 if (index == 0) st->print_cr(" -------------");
615 // print entry
616 st->print("%3d (" PTR_FORMAT ") ", index, (intptr_t)this);
617 st->print_cr("[%02x|%02x|%5d]", bytecode_2(), bytecode_1(),
618 constant_pool_index());
619 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f1);
620 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_f2);
621 st->print_cr(" [ " PTR_FORMAT "]", (intptr_t)_flags);
622 st->print_cr(" -------------");
623 }
624
625 void ConstantPoolCacheEntry::verify(outputStream* st) const {
626 // not implemented yet
627 }
628
629 // Implementation of ConstantPoolCache
630
631 ConstantPoolCache* ConstantPoolCache::allocate(ClassLoaderData* loader_data,
632 const intStack& index_map,
633 const intStack& invokedynamic_index_map,
634 const intStack& invokedynamic_map, TRAPS) {
635
636 const int length = index_map.length() + invokedynamic_index_map.length();
637 int size = ConstantPoolCache::size(length);
638
639 return new (loader_data, size, MetaspaceObj::ConstantPoolCacheType, THREAD)
640 ConstantPoolCache(length, index_map, invokedynamic_index_map, invokedynamic_map);
641 }
642
643 void ConstantPoolCache::initialize(const intArray& inverse_index_map,
644 const intArray& invokedynamic_inverse_index_map,
645 const intArray& invokedynamic_references_map) {
646 for (int i = 0; i < inverse_index_map.length(); i++) {
647 ConstantPoolCacheEntry* e = entry_at(i);
648 int original_index = inverse_index_map.at(i);
649 e->initialize_entry(original_index);
650 assert(entry_at(i) == e, "sanity");
651 }
652
653 // Append invokedynamic entries at the end
654 int invokedynamic_offset = inverse_index_map.length();
655 for (int i = 0; i < invokedynamic_inverse_index_map.length(); i++) {
656 int offset = i + invokedynamic_offset;
657 ConstantPoolCacheEntry* e = entry_at(offset);
658 int original_index = invokedynamic_inverse_index_map.at(i);
659 e->initialize_entry(original_index);
660 assert(entry_at(offset) == e, "sanity");
661 }
662
663 for (int ref = 0; ref < invokedynamic_references_map.length(); ref++) {
664 const int cpci = invokedynamic_references_map.at(ref);
665 if (cpci >= 0) {
666 #ifdef ASSERT
667 // invokedynamic and invokehandle have more entries; check if they
668 // all point to the same constant pool cache entry.
669 for (int entry = 1; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
670 const int cpci_next = invokedynamic_references_map.at(ref + entry);
671 assert(cpci == cpci_next, "%d == %d", cpci, cpci_next);
672 }
673 #endif
674 entry_at(cpci)->initialize_resolved_reference_index(ref);
675 ref += ConstantPoolCacheEntry::_indy_resolved_references_entries - 1; // skip extra entries
676 }
677 }
678 }
679
680 void ConstantPoolCache::verify_just_initialized() {
681 DEBUG_ONLY(walk_entries_for_initialization(/*check_only = */ true));
682 }
683
684 void ConstantPoolCache::remove_unshareable_info() {
685 walk_entries_for_initialization(/*check_only = */ false);
686 }
687
688 void ConstantPoolCache::walk_entries_for_initialization(bool check_only) {
689 assert(DumpSharedSpaces, "sanity");
690 // When dumping the archive, we want to clean up the ConstantPoolCache
691 // to remove any effect of linking due to the execution of Java code --
692 // each ConstantPoolCacheEntry will have the same contents as if
693 // ConstantPoolCache::initialize has just returned:
694 //
695 // - We keep the ConstantPoolCache::constant_pool_index() bits for all entries.
696 // - We keep the "f2" field for entries used by invokedynamic and invokehandle
697 // - All other bits in the entries are cleared to zero.
698 ResourceMark rm;
699
700 InstanceKlass* ik = constant_pool()->pool_holder();
701 bool* f2_used = NEW_RESOURCE_ARRAY(bool, length());
702 memset(f2_used, 0, sizeof(bool) * length());
703
704 // Find all the slots that we need to preserve f2
705 for (int i = 0; i < ik->methods()->length(); i++) {
706 Method* m = ik->methods()->at(i);
707 RawBytecodeStream bcs(m);
708 while (!bcs.is_last_bytecode()) {
709 Bytecodes::Code opcode = bcs.raw_next();
710 switch (opcode) {
711 case Bytecodes::_invokedynamic: {
712 int index = Bytes::get_native_u4(bcs.bcp() + 1);
713 int cp_cache_index = constant_pool()->invokedynamic_cp_cache_index(index);
714 f2_used[cp_cache_index] = 1;
715 }
716 break;
717 case Bytecodes::_invokehandle: {
718 int cp_cache_index = Bytes::get_native_u2(bcs.bcp() + 1);
719 f2_used[cp_cache_index] = 1;
720 }
721 break;
722 default:
723 break;
724 }
725 }
726 }
727
728 if (check_only) {
729 DEBUG_ONLY(
730 for (int i=0; i<length(); i++) {
731 entry_at(i)->verify_just_initialized(f2_used[i]);
732 })
733 } else {
734 for (int i=0; i<length(); i++) {
735 entry_at(i)->reinitialize(f2_used[i]);
736 }
737 }
738 }
739
740 void ConstantPoolCache::deallocate_contents(ClassLoaderData* data) {
741 assert(!is_shared(), "shared caches are not deallocated");
742 data->remove_handle(_resolved_references);
743 set_resolved_references(NULL);
744 MetadataFactory::free_array<u2>(data, _reference_map);
745 set_reference_map(NULL);
746 }
747
748 #if INCLUDE_CDS_JAVA_HEAP
749 oop ConstantPoolCache::archived_references() {
750 // Loading an archive root forces the oop to become strongly reachable.
751 // For example, if it is loaded during concurrent marking in a SATB
752 // collector, it will be enqueued to the SATB queue, effectively
753 // shading the previously white object gray.
754 return RootAccess<IN_ARCHIVE_ROOT>::oop_load(&_archived_references);
755 }
756
757 void ConstantPoolCache::set_archived_references(oop o) {
758 assert(DumpSharedSpaces, "called only during runtime");
759 RootAccess<IN_ARCHIVE_ROOT>::oop_store(&_archived_references, o);
760 }
761 #endif
762
763 #if INCLUDE_JVMTI
764 // RedefineClasses() API support:
765 // If any entry of this ConstantPoolCache points to any of
766 // old_methods, replace it with the corresponding new_method.
767 void ConstantPoolCache::adjust_method_entries(InstanceKlass* holder, bool * trace_name_printed) {
768 for (int i = 0; i < length(); i++) {
769 ConstantPoolCacheEntry* entry = entry_at(i);
770 Method* old_method = entry->get_interesting_method_entry(holder);
771 if (old_method == NULL || !old_method->is_old()) {
772 continue; // skip uninteresting entries
773 }
774 if (old_method->is_deleted()) {
775 // clean up entries with deleted methods
776 entry->initialize_entry(entry->constant_pool_index());
777 continue;
778 }
779 Method* new_method = holder->method_with_idnum(old_method->orig_method_idnum());
780
781 assert(new_method != NULL, "method_with_idnum() should not be NULL");
782 assert(old_method != new_method, "sanity check");
783
784 entry_at(i)->adjust_method_entry(old_method, new_method, trace_name_printed);
785 }
786 }
787
788 // the constant pool cache should never contain old or obsolete methods
789 bool ConstantPoolCache::check_no_old_or_obsolete_entries() {
790 for (int i = 1; i < length(); i++) {
791 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL &&
792 !entry_at(i)->check_no_old_or_obsolete_entries()) {
793 return false;
794 }
795 }
796 return true;
797 }
798
799 void ConstantPoolCache::dump_cache() {
800 for (int i = 1; i < length(); i++) {
801 if (entry_at(i)->get_interesting_method_entry(NULL) != NULL) {
802 entry_at(i)->print(tty, i);
803 }
804 }
805 }
806 #endif // INCLUDE_JVMTI
807
808 void ConstantPoolCache::metaspace_pointers_do(MetaspaceClosure* it) {
809 log_trace(cds)("Iter(ConstantPoolCache): %p", this);
810 it->push(&_constant_pool);
811 it->push(&_reference_map);
812 }
813
814 // Printing
815
816 void ConstantPoolCache::print_on(outputStream* st) const {
817 assert(is_constantPoolCache(), "obj must be constant pool cache");
818 st->print_cr("%s", internal_name());
819 // print constant pool cache entries
820 for (int i = 0; i < length(); i++) entry_at(i)->print(st, i);
821 }
822
823 void ConstantPoolCache::print_value_on(outputStream* st) const {
824 assert(is_constantPoolCache(), "obj must be constant pool cache");
825 st->print("cache [%d]", length());
826 print_address_on(st);
827 st->print(" for ");
828 constant_pool()->print_value_on(st);
829 }
830
831
832 // Verification
833
834 void ConstantPoolCache::verify_on(outputStream* st) {
835 guarantee(is_constantPoolCache(), "obj must be constant pool cache");
836 // print constant pool cache entries
837 for (int i = 0; i < length(); i++) entry_at(i)->verify(st);
838 }