1 /*
2 * Copyright (c) 1997, 2024, 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 "cds/cdsConfig.hpp"
27 #include "cds/cppVtables.hpp"
28 #include "cds/metaspaceShared.hpp"
29 #include "classfile/classLoaderDataGraph.hpp"
30 #include "classfile/metadataOnStackMark.hpp"
31 #include "classfile/symbolTable.hpp"
32 #include "classfile/systemDictionary.hpp"
33 #include "classfile/vmClasses.hpp"
34 #include "code/codeCache.hpp"
35 #include "code/debugInfoRec.hpp"
36 #include "compiler/compilationPolicy.hpp"
37 #include "gc/shared/collectedHeap.inline.hpp"
38 #include "interpreter/bytecodeStream.hpp"
39 #include "interpreter/bytecodeTracer.hpp"
40 #include "interpreter/bytecodes.hpp"
41 #include "interpreter/interpreter.hpp"
42 #include "interpreter/oopMapCache.hpp"
43 #include "logging/log.hpp"
44 #include "logging/logStream.hpp"
45 #include "logging/logTag.hpp"
46 #include "memory/allocation.inline.hpp"
47 #include "memory/metadataFactory.hpp"
48 #include "memory/metaspaceClosure.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "nmt/memTracker.hpp"
53 #include "oops/constMethod.hpp"
54 #include "oops/constantPool.hpp"
55 #include "oops/klass.inline.hpp"
56 #include "oops/method.inline.hpp"
57 #include "oops/methodData.hpp"
58 #include "oops/objArrayKlass.hpp"
59 #include "oops/objArrayOop.inline.hpp"
60 #include "oops/oop.inline.hpp"
61 #include "oops/symbol.hpp"
62 #include "prims/jvmtiExport.hpp"
63 #include "prims/methodHandles.hpp"
64 #include "runtime/atomic.hpp"
65 #include "runtime/continuationEntry.hpp"
66 #include "runtime/frame.inline.hpp"
67 #include "runtime/handles.inline.hpp"
68 #include "runtime/init.hpp"
69 #include "runtime/java.hpp"
70 #include "runtime/orderAccess.hpp"
71 #include "runtime/relocator.hpp"
72 #include "runtime/safepointVerifiers.hpp"
73 #include "runtime/sharedRuntime.hpp"
74 #include "runtime/signature.hpp"
75 #include "runtime/threads.hpp"
76 #include "runtime/vm_version.hpp"
77 #include "utilities/align.hpp"
78 #include "utilities/quickSort.hpp"
79 #include "utilities/vmError.hpp"
80 #include "utilities/xmlstream.hpp"
81
82 // Implementation of Method
83
84 Method* Method::allocate(ClassLoaderData* loader_data,
85 int byte_code_size,
86 AccessFlags access_flags,
87 InlineTableSizes* sizes,
88 ConstMethod::MethodType method_type,
89 Symbol* name,
90 TRAPS) {
91 assert(!access_flags.is_native() || byte_code_size == 0,
92 "native methods should not contain byte codes");
93 ConstMethod* cm = ConstMethod::allocate(loader_data,
94 byte_code_size,
95 sizes,
96 method_type,
97 CHECK_NULL);
98 int size = Method::size(access_flags.is_native());
99 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, name);
100 }
101
102 Method::Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name) {
103 NoSafepointVerifier no_safepoint;
104 set_constMethod(xconst);
105 set_access_flags(access_flags);
106 set_intrinsic_id(vmIntrinsics::_none);
107 clear_method_data();
108 clear_method_counters();
109 set_vtable_index(Method::garbage_vtable_index);
110
111 // Fix and bury in Method*
112 set_interpreter_entry(nullptr); // sets i2i entry and from_int
113 set_adapter_entry(nullptr);
114 Method::clear_code(); // from_c/from_i get set to c2i/i2i
115
116 if (access_flags.is_native()) {
117 clear_native_function();
118 set_signature_handler(nullptr);
119 }
120
121 NOT_PRODUCT(set_compiled_invocation_count(0);)
122 // Name is very useful for debugging.
123 NOT_PRODUCT(_name = name;)
124 }
125
126 // Release Method*. The nmethod will be gone when we get here because
127 // we've walked the code cache.
128 void Method::deallocate_contents(ClassLoaderData* loader_data) {
129 MetadataFactory::free_metadata(loader_data, constMethod());
130 set_constMethod(nullptr);
131 MetadataFactory::free_metadata(loader_data, method_data());
132 clear_method_data();
133 MetadataFactory::free_metadata(loader_data, method_counters());
134 clear_method_counters();
135 // The nmethod will be gone when we get here.
136 if (code() != nullptr) _code = nullptr;
137 }
138
139 void Method::release_C_heap_structures() {
140 if (method_data()) {
141 method_data()->release_C_heap_structures();
142
143 // Destroy MethodData embedded lock
144 method_data()->~MethodData();
145 }
146 }
147
148 address Method::get_i2c_entry() {
149 assert(adapter() != nullptr, "must have");
150 return adapter()->get_i2c_entry();
151 }
152
153 address Method::get_c2i_entry() {
154 assert(adapter() != nullptr, "must have");
155 return adapter()->get_c2i_entry();
156 }
157
158 address Method::get_c2i_unverified_entry() {
159 assert(adapter() != nullptr, "must have");
160 return adapter()->get_c2i_unverified_entry();
161 }
162
163 address Method::get_c2i_no_clinit_check_entry() {
164 assert(VM_Version::supports_fast_class_init_checks(), "");
165 assert(adapter() != nullptr, "must have");
166 return adapter()->get_c2i_no_clinit_check_entry();
167 }
168
169 char* Method::name_and_sig_as_C_string() const {
170 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
171 }
172
173 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
174 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
175 }
176
177 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
178 const char* klass_name = klass->external_name();
179 int klass_name_len = (int)strlen(klass_name);
180 int method_name_len = method_name->utf8_length();
181 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
182 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
183 strcpy(dest, klass_name);
184 dest[klass_name_len] = '.';
185 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
186 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
187 dest[len] = 0;
188 return dest;
189 }
190
191 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
192 Symbol* klass_name = klass->name();
193 klass_name->as_klass_external_name(buf, size);
194 int len = (int)strlen(buf);
195
196 if (len < size - 1) {
197 buf[len++] = '.';
198
199 method_name->as_C_string(&(buf[len]), size - len);
200 len = (int)strlen(buf);
201
202 signature->as_C_string(&(buf[len]), size - len);
203 }
204
205 return buf;
206 }
207
208 const char* Method::external_name() const {
209 return external_name(constants()->pool_holder(), name(), signature());
210 }
211
212 void Method::print_external_name(outputStream *os) const {
213 print_external_name(os, constants()->pool_holder(), name(), signature());
214 }
215
216 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
217 stringStream ss;
218 print_external_name(&ss, klass, method_name, signature);
219 return ss.as_string();
220 }
221
222 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
223 signature->print_as_signature_external_return_type(os);
224 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
225 signature->print_as_signature_external_parameters(os);
226 os->print(")");
227 }
228
229 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
230 if (log_is_enabled(Debug, exceptions)) {
231 ResourceMark rm(THREAD);
232 log_debug(exceptions)("Looking for catch handler for exception of type \"%s\" in method \"%s\"",
233 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string());
234 }
235 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
236 // access exception table
237 ExceptionTable table(mh());
238 int length = table.length();
239 // iterate through all entries sequentially
240 constantPoolHandle pool(THREAD, mh->constants());
241 for (int i = 0; i < length; i ++) {
242 //reacquire the table in case a GC happened
243 ExceptionTable table(mh());
244 int beg_bci = table.start_pc(i);
245 int end_bci = table.end_pc(i);
246 assert(beg_bci <= end_bci, "inconsistent exception table");
247 log_debug(exceptions)(" - checking exception table entry for BCI %d to %d",
248 beg_bci, end_bci);
249
250 if (beg_bci <= throw_bci && throw_bci < end_bci) {
251 // exception handler bci range covers throw_bci => investigate further
252 log_debug(exceptions)(" - entry covers throw point BCI %d", throw_bci);
253
254 int handler_bci = table.handler_pc(i);
255 int klass_index = table.catch_type_index(i);
256 if (klass_index == 0) {
257 if (log_is_enabled(Info, exceptions)) {
258 ResourceMark rm(THREAD);
259 log_info(exceptions)("Found catch-all handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
260 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
261 }
262 return handler_bci;
263 } else if (ex_klass == nullptr) {
264 // Is this even possible?
265 if (log_is_enabled(Info, exceptions)) {
266 ResourceMark rm(THREAD);
267 log_info(exceptions)("null exception class is implicitly caught by handler in method \"%s\" at BCI: %d",
268 mh()->name()->as_C_string(), handler_bci);
269 }
270 return handler_bci;
271 } else {
272 if (log_is_enabled(Debug, exceptions)) {
273 ResourceMark rm(THREAD);
274 log_debug(exceptions)(" - resolving catch type \"%s\"",
275 pool->klass_name_at(klass_index)->as_C_string());
276 }
277 // we know the exception class => get the constraint class
278 // this may require loading of the constraint class; if verification
279 // fails or some other exception occurs, return handler_bci
280 Klass* k = pool->klass_at(klass_index, THREAD);
281 if (HAS_PENDING_EXCEPTION) {
282 if (log_is_enabled(Debug, exceptions)) {
283 ResourceMark rm(THREAD);
284 log_debug(exceptions)(" - exception \"%s\" occurred resolving catch type",
285 PENDING_EXCEPTION->klass()->external_name());
286 }
287 return handler_bci;
288 }
289 assert(k != nullptr, "klass not loaded");
290 if (ex_klass->is_subtype_of(k)) {
291 if (log_is_enabled(Info, exceptions)) {
292 ResourceMark rm(THREAD);
293 log_info(exceptions)("Found matching handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
294 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
295 }
296 return handler_bci;
297 }
298 }
299 }
300 }
301
302 if (log_is_enabled(Debug, exceptions)) {
303 ResourceMark rm(THREAD);
304 log_debug(exceptions)("No catch handler found for exception of type \"%s\" in method \"%s\"",
305 ex_klass->external_name(), mh->name()->as_C_string());
306 }
307
308 return -1;
309 }
310
311 void Method::mask_for(int bci, InterpreterOopMap* mask) {
312 methodHandle h_this(Thread::current(), this);
313 // Only GC uses the OopMapCache during thread stack root scanning
314 // any other uses generate an oopmap but do not save it in the cache.
315 if (Universe::heap()->is_stw_gc_active()) {
316 method_holder()->mask_for(h_this, bci, mask);
317 } else {
318 OopMapCache::compute_one_oop_map(h_this, bci, mask);
319 }
320 return;
321 }
322
323
324 int Method::bci_from(address bcp) const {
325 if (is_native() && bcp == 0) {
326 return 0;
327 }
328 // Do not have a ResourceMark here because AsyncGetCallTrace stack walking code
329 // may call this after interrupting a nested ResourceMark.
330 assert((is_native() && bcp == code_base()) || contains(bcp) || VMError::is_error_reported(),
331 "bcp doesn't belong to this method. bcp: " PTR_FORMAT, p2i(bcp));
332
333 return int(bcp - code_base());
334 }
335
336
337 int Method::validate_bci(int bci) const {
338 return (bci == 0 || bci < code_size()) ? bci : -1;
339 }
340
341 // Return bci if it appears to be a valid bcp
342 // Return -1 otherwise.
343 // Used by profiling code, when invalid data is a possibility.
344 // The caller is responsible for validating the Method* itself.
345 int Method::validate_bci_from_bcp(address bcp) const {
346 // keep bci as -1 if not a valid bci
347 int bci = -1;
348 if (bcp == 0 || bcp == code_base()) {
349 // code_size() may return 0 and we allow 0 here
350 // the method may be native
351 bci = 0;
352 } else if (contains(bcp)) {
353 bci = int(bcp - code_base());
354 }
355 // Assert that if we have dodged any asserts, bci is negative.
356 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
357 return bci;
358 }
359
360 address Method::bcp_from(int bci) const {
361 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
362 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
363 address bcp = code_base() + bci;
364 assert((is_native() && bcp == code_base()) || contains(bcp), "bcp doesn't belong to this method");
365 return bcp;
366 }
367
368 address Method::bcp_from(address bcp) const {
369 if (is_native() && bcp == nullptr) {
370 return code_base();
371 } else {
372 return bcp;
373 }
374 }
375
376 int Method::size(bool is_native) {
377 // If native, then include pointers for native_function and signature_handler
378 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
379 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
380 return align_metadata_size(header_size() + extra_words);
381 }
382
383 Symbol* Method::klass_name() const {
384 return method_holder()->name();
385 }
386
387 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
388 log_trace(cds)("Iter(Method): %p", this);
389
390 if (!method_holder()->is_rewritten()) {
391 it->push(&_constMethod, MetaspaceClosure::_writable);
392 } else {
393 it->push(&_constMethod);
394 }
395 it->push(&_method_data);
396 it->push(&_method_counters);
397 NOT_PRODUCT(it->push(&_name);)
398 }
399
400 #if INCLUDE_CDS
401 // Attempt to return method to original state. Clear any pointers
402 // (to objects outside the shared spaces). We won't be able to predict
403 // where they should point in a new JVM. Further initialize some
404 // entries now in order allow them to be write protected later.
405
406 void Method::remove_unshareable_info() {
407 unlink_method();
408 JFR_ONLY(REMOVE_METHOD_ID(this);)
409 }
410
411 void Method::restore_unshareable_info(TRAPS) {
412 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
413 assert(!queued_for_compilation(), "method's queued_for_compilation flag should not be set");
414 }
415 #endif
416
417 void Method::set_vtable_index(int index) {
418 if (is_shared() && !MetaspaceShared::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
419 // At runtime initialize_vtable is rerun as part of link_class_impl()
420 // for a shared class loaded by the non-boot loader to obtain the loader
421 // constraints based on the runtime classloaders' context.
422 return; // don't write into the shared class
423 } else {
424 _vtable_index = index;
425 }
426 }
427
428 void Method::set_itable_index(int index) {
429 if (is_shared() && !MetaspaceShared::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
430 // At runtime initialize_itable is rerun as part of link_class_impl()
431 // for a shared class loaded by the non-boot loader to obtain the loader
432 // constraints based on the runtime classloaders' context. The dumptime
433 // itable index should be the same as the runtime index.
434 assert(_vtable_index == itable_index_max - index,
435 "archived itable index is different from runtime index");
436 return; // don’t write into the shared class
437 } else {
438 _vtable_index = itable_index_max - index;
439 }
440 assert(valid_itable_index(), "");
441 }
442
443 // The RegisterNatives call being attempted tried to register with a method that
444 // is not native. Ask JVM TI what prefixes have been specified. Then check
445 // to see if the native method is now wrapped with the prefixes. See the
446 // SetNativeMethodPrefix(es) functions in the JVM TI Spec for details.
447 static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS) {
448 #if INCLUDE_JVMTI
449 ResourceMark rm(THREAD);
450 Method* method;
451 int name_len = name->utf8_length();
452 char* name_str = name->as_utf8();
453 int prefix_count;
454 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
455 for (int i = 0; i < prefix_count; i++) {
456 char* prefix = prefixes[i];
457 int prefix_len = (int)strlen(prefix);
458
459 // try adding this prefix to the method name and see if it matches another method name
460 int trial_len = name_len + prefix_len;
461 char* trial_name_str = NEW_RESOURCE_ARRAY(char, trial_len + 1);
462 strcpy(trial_name_str, prefix);
463 strcat(trial_name_str, name_str);
464 TempNewSymbol trial_name = SymbolTable::probe(trial_name_str, trial_len);
465 if (trial_name == nullptr) {
466 continue; // no such symbol, so this prefix wasn't used, try the next prefix
467 }
468 method = k->lookup_method(trial_name, signature);
469 if (method == nullptr) {
470 continue; // signature doesn't match, try the next prefix
471 }
472 if (method->is_native()) {
473 method->set_is_prefixed_native();
474 return method; // wahoo, we found a prefixed version of the method, return it
475 }
476 // found as non-native, so prefix is good, add it, probably just need more prefixes
477 name_len = trial_len;
478 name_str = trial_name_str;
479 }
480 #endif // INCLUDE_JVMTI
481 return nullptr; // not found
482 }
483
484 bool Method::register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS) {
485 Method* method = k->lookup_method(name, signature);
486 if (method == nullptr) {
487 ResourceMark rm(THREAD);
488 stringStream st;
489 st.print("Method '");
490 print_external_name(&st, k, name, signature);
491 st.print("' name or signature does not match");
492 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
493 }
494 if (!method->is_native()) {
495 // trying to register to a non-native method, see if a JVM TI agent has added prefix(es)
496 method = find_prefixed_native(k, name, signature, THREAD);
497 if (method == nullptr) {
498 ResourceMark rm(THREAD);
499 stringStream st;
500 st.print("Method '");
501 print_external_name(&st, k, name, signature);
502 st.print("' is not declared as native");
503 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
504 }
505 }
506
507 if (entry != nullptr) {
508 method->set_native_function(entry, native_bind_event_is_interesting);
509 } else {
510 method->clear_native_function();
511 }
512 if (log_is_enabled(Debug, jni, resolve)) {
513 ResourceMark rm(THREAD);
514 log_debug(jni, resolve)("[Registering JNI native method %s.%s]",
515 method->method_holder()->external_name(),
516 method->name()->as_C_string());
517 }
518 return true;
519 }
520
521 bool Method::was_executed_more_than(int n) {
522 // Invocation counter is reset when the Method* is compiled.
523 // If the method has compiled code we therefore assume it has
524 // be executed more than n times.
525 if (is_accessor() || is_empty_method() || (code() != nullptr)) {
526 // interpreter doesn't bump invocation counter of trivial methods
527 // compiler does not bump invocation counter of compiled methods
528 return true;
529 }
530 else if ((method_counters() != nullptr &&
531 method_counters()->invocation_counter()->carry()) ||
532 (method_data() != nullptr &&
533 method_data()->invocation_counter()->carry())) {
534 // The carry bit is set when the counter overflows and causes
535 // a compilation to occur. We don't know how many times
536 // the counter has been reset, so we simply assume it has
537 // been executed more than n times.
538 return true;
539 } else {
540 return invocation_count() > n;
541 }
542 }
543
544 void Method::print_invocation_count(outputStream* st) {
545 //---< compose+print method return type, klass, name, and signature >---
546 if (is_static()) { st->print("static "); }
547 if (is_final()) { st->print("final "); }
548 if (is_synchronized()) { st->print("synchronized "); }
549 if (is_native()) { st->print("native "); }
550 st->print("%s::", method_holder()->external_name());
551 name()->print_symbol_on(st);
552 signature()->print_symbol_on(st);
553
554 if (WizardMode) {
555 // dump the size of the byte codes
556 st->print(" {%d}", code_size());
557 }
558 st->cr();
559
560 // Counting based on signed int counters tends to overflow with
561 // longer-running workloads on fast machines. The counters under
562 // consideration here, however, are limited in range by counting
563 // logic. See InvocationCounter:count_limit for example.
564 // No "overflow precautions" need to be implemented here.
565 st->print_cr (" interpreter_invocation_count: " INT32_FORMAT_W(11), interpreter_invocation_count());
566 st->print_cr (" invocation_counter: " INT32_FORMAT_W(11), invocation_count());
567 st->print_cr (" backedge_counter: " INT32_FORMAT_W(11), backedge_count());
568
569 if (method_data() != nullptr) {
570 st->print_cr (" decompile_count: " UINT32_FORMAT_W(11), method_data()->decompile_count());
571 }
572
573 #ifndef PRODUCT
574 if (CountCompiledCalls) {
575 st->print_cr (" compiled_invocation_count: " INT64_FORMAT_W(11), compiled_invocation_count());
576 }
577 #endif
578 }
579
580 // Build a MethodData* object to hold profiling information collected on this
581 // method when requested.
582 void Method::build_profiling_method_data(const methodHandle& method, TRAPS) {
583 // Do not profile the method if metaspace has hit an OOM previously
584 // allocating profiling data. Callers clear pending exception so don't
585 // add one here.
586 if (ClassLoaderDataGraph::has_metaspace_oom()) {
587 return;
588 }
589
590 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
591 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
592 if (HAS_PENDING_EXCEPTION) {
593 CompileBroker::log_metaspace_failure();
594 ClassLoaderDataGraph::set_metaspace_oom(true);
595 return; // return the exception (which is cleared)
596 }
597
598 if (!Atomic::replace_if_null(&method->_method_data, method_data)) {
599 MetadataFactory::free_metadata(loader_data, method_data);
600 return;
601 }
602
603 if (PrintMethodData && (Verbose || WizardMode)) {
604 ResourceMark rm(THREAD);
605 tty->print("build_profiling_method_data for ");
606 method->print_name(tty);
607 tty->cr();
608 // At the end of the run, the MDO, full of data, will be dumped.
609 }
610 }
611
612 MethodCounters* Method::build_method_counters(Thread* current, Method* m) {
613 // Do not profile the method if metaspace has hit an OOM previously
614 if (ClassLoaderDataGraph::has_metaspace_oom()) {
615 return nullptr;
616 }
617
618 methodHandle mh(current, m);
619 MethodCounters* counters;
620 if (current->is_Java_thread()) {
621 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
622 // Use the TRAPS version for a JavaThread so it will adjust the GC threshold
623 // if needed.
624 counters = MethodCounters::allocate_with_exception(mh, THREAD);
625 if (HAS_PENDING_EXCEPTION) {
626 CLEAR_PENDING_EXCEPTION;
627 }
628 } else {
629 // Call metaspace allocation that doesn't throw exception if the
630 // current thread isn't a JavaThread, ie. the VMThread.
631 counters = MethodCounters::allocate_no_exception(mh);
632 }
633
634 if (counters == nullptr) {
635 CompileBroker::log_metaspace_failure();
636 ClassLoaderDataGraph::set_metaspace_oom(true);
637 return nullptr;
638 }
639
640 if (!mh->init_method_counters(counters)) {
641 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
642 }
643
644 return mh->method_counters();
645 }
646
647 bool Method::init_method_counters(MethodCounters* counters) {
648 // Try to install a pointer to MethodCounters, return true on success.
649 return Atomic::replace_if_null(&_method_counters, counters);
650 }
651
652 void Method::set_exception_handler_entered(int handler_bci) {
653 if (ProfileExceptionHandlers) {
654 MethodData* mdo = method_data();
655 if (mdo != nullptr) {
656 BitData handler_data = mdo->exception_handler_bci_to_data(handler_bci);
657 handler_data.set_exception_handler_entered();
658 }
659 }
660 }
661
662 int Method::extra_stack_words() {
663 // not an inline function, to avoid a header dependency on Interpreter
664 return extra_stack_entries() * Interpreter::stackElementSize;
665 }
666
667 bool Method::is_vanilla_constructor() const {
668 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
669 // which only calls the superclass vanilla constructor and possibly does stores of
670 // zero constants to local fields:
671 //
672 // aload_0
673 // invokespecial
674 // indexbyte1
675 // indexbyte2
676 //
677 // followed by an (optional) sequence of:
678 //
679 // aload_0
680 // aconst_null / iconst_0 / fconst_0 / dconst_0
681 // putfield
682 // indexbyte1
683 // indexbyte2
684 //
685 // followed by:
686 //
687 // return
688
689 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
690 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
691 int size = code_size();
692 // Check if size match
693 if (size == 0 || size % 5 != 0) return false;
694 address cb = code_base();
695 int last = size - 1;
696 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
697 // Does not call superclass default constructor
698 return false;
699 }
700 // Check optional sequence
701 for (int i = 4; i < last; i += 5) {
702 if (cb[i] != Bytecodes::_aload_0) return false;
703 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
704 if (cb[i+2] != Bytecodes::_putfield) return false;
705 }
706 return true;
707 }
708
709
710 bool Method::compute_has_loops_flag() {
711 BytecodeStream bcs(methodHandle(Thread::current(), this));
712 Bytecodes::Code bc;
713
714 while ((bc = bcs.next()) >= 0) {
715 switch (bc) {
716 case Bytecodes::_ifeq:
717 case Bytecodes::_ifnull:
718 case Bytecodes::_iflt:
719 case Bytecodes::_ifle:
720 case Bytecodes::_ifne:
721 case Bytecodes::_ifnonnull:
722 case Bytecodes::_ifgt:
723 case Bytecodes::_ifge:
724 case Bytecodes::_if_icmpeq:
725 case Bytecodes::_if_icmpne:
726 case Bytecodes::_if_icmplt:
727 case Bytecodes::_if_icmpgt:
728 case Bytecodes::_if_icmple:
729 case Bytecodes::_if_icmpge:
730 case Bytecodes::_if_acmpeq:
731 case Bytecodes::_if_acmpne:
732 case Bytecodes::_goto:
733 case Bytecodes::_jsr:
734 if (bcs.dest() < bcs.next_bci()) {
735 return set_has_loops();
736 }
737 break;
738
739 case Bytecodes::_goto_w:
740 case Bytecodes::_jsr_w:
741 if (bcs.dest_w() < bcs.next_bci()) {
742 return set_has_loops();
743 }
744 break;
745
746 case Bytecodes::_lookupswitch: {
747 Bytecode_lookupswitch lookupswitch(this, bcs.bcp());
748 if (lookupswitch.default_offset() < 0) {
749 return set_has_loops();
750 } else {
751 for (int i = 0; i < lookupswitch.number_of_pairs(); ++i) {
752 LookupswitchPair pair = lookupswitch.pair_at(i);
753 if (pair.offset() < 0) {
754 return set_has_loops();
755 }
756 }
757 }
758 break;
759 }
760 case Bytecodes::_tableswitch: {
761 Bytecode_tableswitch tableswitch(this, bcs.bcp());
762 if (tableswitch.default_offset() < 0) {
763 return set_has_loops();
764 } else {
765 for (int i = 0; i < tableswitch.length(); ++i) {
766 if (tableswitch.dest_offset_at(i) < 0) {
767 return set_has_loops();
768 }
769 }
770 }
771 break;
772 }
773 default:
774 break;
775 }
776 }
777
778 _flags.set_has_loops_flag_init(true);
779 return false;
780 }
781
782 bool Method::is_final_method(AccessFlags class_access_flags) const {
783 // or "does_not_require_vtable_entry"
784 // default method or overpass can occur, is not final (reuses vtable entry)
785 // private methods in classes get vtable entries for backward class compatibility.
786 if (is_overpass() || is_default_method()) return false;
787 return is_final() || class_access_flags.is_final();
788 }
789
790 bool Method::is_final_method() const {
791 return is_final_method(method_holder()->access_flags());
792 }
793
794 bool Method::is_default_method() const {
795 if (method_holder() != nullptr &&
796 method_holder()->is_interface() &&
797 !is_abstract() && !is_private()) {
798 return true;
799 } else {
800 return false;
801 }
802 }
803
804 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
805 if (is_final_method(class_access_flags)) return true;
806 #ifdef ASSERT
807 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
808 if (class_access_flags.is_interface()) {
809 ResourceMark rm;
810 assert(is_nonv == is_static() || is_nonv == is_private(),
811 "nonvirtual unexpected for non-static, non-private: %s",
812 name_and_sig_as_C_string());
813 }
814 #endif
815 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
816 return vtable_index() == nonvirtual_vtable_index;
817 }
818
819 bool Method::can_be_statically_bound() const {
820 return can_be_statically_bound(method_holder()->access_flags());
821 }
822
823 bool Method::can_be_statically_bound(InstanceKlass* context) const {
824 return (method_holder() == context) && can_be_statically_bound();
825 }
826
827 /**
828 * Returns false if this is one of specially treated methods for
829 * which we have to provide stack trace in throw in compiled code.
830 * Returns true otherwise.
831 */
832 bool Method::can_omit_stack_trace() {
833 if (klass_name() == vmSymbols::sun_invoke_util_ValueConversions()) {
834 return false; // All methods in sun.invoke.util.ValueConversions
835 }
836 return true;
837 }
838
839 bool Method::is_accessor() const {
840 return is_getter() || is_setter();
841 }
842
843 bool Method::is_getter() const {
844 if (code_size() != 5) return false;
845 if (size_of_parameters() != 1) return false;
846 if (java_code_at(0) != Bytecodes::_aload_0) return false;
847 if (java_code_at(1) != Bytecodes::_getfield) return false;
848 switch (java_code_at(4)) {
849 case Bytecodes::_ireturn:
850 case Bytecodes::_lreturn:
851 case Bytecodes::_freturn:
852 case Bytecodes::_dreturn:
853 case Bytecodes::_areturn:
854 break;
855 default:
856 return false;
857 }
858 return true;
859 }
860
861 bool Method::is_setter() const {
862 if (code_size() != 6) return false;
863 if (java_code_at(0) != Bytecodes::_aload_0) return false;
864 switch (java_code_at(1)) {
865 case Bytecodes::_iload_1:
866 case Bytecodes::_aload_1:
867 case Bytecodes::_fload_1:
868 if (size_of_parameters() != 2) return false;
869 break;
870 case Bytecodes::_dload_1:
871 case Bytecodes::_lload_1:
872 if (size_of_parameters() != 3) return false;
873 break;
874 default:
875 return false;
876 }
877 if (java_code_at(2) != Bytecodes::_putfield) return false;
878 if (java_code_at(5) != Bytecodes::_return) return false;
879 return true;
880 }
881
882 bool Method::is_constant_getter() const {
883 int last_index = code_size() - 1;
884 // Check if the first 1-3 bytecodes are a constant push
885 // and the last bytecode is a return.
886 return (2 <= code_size() && code_size() <= 4 &&
887 Bytecodes::is_const(java_code_at(0)) &&
888 Bytecodes::length_for(java_code_at(0)) == last_index &&
889 Bytecodes::is_return(java_code_at(last_index)));
890 }
891
892 bool Method::is_initializer() const {
893 return is_object_initializer() || is_static_initializer();
894 }
895
896 bool Method::has_valid_initializer_flags() const {
897 return (is_static() ||
898 method_holder()->major_version() < 51);
899 }
900
901 bool Method::is_static_initializer() const {
902 // For classfiles version 51 or greater, ensure that the clinit method is
903 // static. Non-static methods with the name "<clinit>" are not static
904 // initializers. (older classfiles exempted for backward compatibility)
905 return name() == vmSymbols::class_initializer_name() &&
906 has_valid_initializer_flags();
907 }
908
909 bool Method::is_object_initializer() const {
910 return name() == vmSymbols::object_initializer_name();
911 }
912
913 bool Method::needs_clinit_barrier() const {
914 return is_static() && !method_holder()->is_initialized();
915 }
916
917 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
918 int length = method->checked_exceptions_length();
919 if (length == 0) { // common case
920 return objArrayHandle(THREAD, Universe::the_empty_class_array());
921 } else {
922 methodHandle h_this(THREAD, method);
923 objArrayOop m_oop = oopFactory::new_objArray(vmClasses::Class_klass(), length, CHECK_(objArrayHandle()));
924 objArrayHandle mirrors (THREAD, m_oop);
925 for (int i = 0; i < length; i++) {
926 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
927 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
928 if (log_is_enabled(Warning, exceptions) &&
929 !k->is_subclass_of(vmClasses::Throwable_klass())) {
930 ResourceMark rm(THREAD);
931 log_warning(exceptions)(
932 "Class %s in throws clause of method %s is not a subtype of class java.lang.Throwable",
933 k->external_name(), method->external_name());
934 }
935 mirrors->obj_at_put(i, k->java_mirror());
936 }
937 return mirrors;
938 }
939 };
940
941
942 int Method::line_number_from_bci(int bci) const {
943 int best_bci = 0;
944 int best_line = -1;
945 if (bci == SynchronizationEntryBCI) bci = 0;
946 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
947 // The line numbers are a short array of 2-tuples [start_pc, line_number].
948 // Not necessarily sorted and not necessarily one-to-one.
949 CompressedLineNumberReadStream stream(compressed_linenumber_table());
950 while (stream.read_pair()) {
951 if (stream.bci() == bci) {
952 // perfect match
953 return stream.line();
954 } else {
955 // update best_bci/line
956 if (stream.bci() < bci && stream.bci() >= best_bci) {
957 best_bci = stream.bci();
958 best_line = stream.line();
959 }
960 }
961 }
962 }
963 return best_line;
964 }
965
966
967 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
968 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
969 Thread *thread = Thread::current();
970 Symbol* klass_name = constants()->klass_name_at(klass_index);
971 Handle loader(thread, method_holder()->class_loader());
972 Handle prot (thread, method_holder()->protection_domain());
973 return SystemDictionary::find_instance_klass(thread, klass_name, loader, prot) != nullptr;
974 } else {
975 return true;
976 }
977 }
978
979
980 bool Method::is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved) const {
981 int klass_index = constants()->klass_ref_index_at(refinfo_index, bc);
982 if (must_be_resolved) {
983 // Make sure klass is resolved in constantpool.
984 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
985 }
986 return is_klass_loaded_by_klass_index(klass_index);
987 }
988
989
990 void Method::set_native_function(address function, bool post_event_flag) {
991 assert(function != nullptr, "use clear_native_function to unregister natives");
992 assert(!is_special_native_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
993 address* native_function = native_function_addr();
994
995 // We can see racers trying to place the same native function into place. Once
996 // is plenty.
997 address current = *native_function;
998 if (current == function) return;
999 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
1000 function != nullptr) {
1001 // native_method_throw_unsatisfied_link_error_entry() should only
1002 // be passed when post_event_flag is false.
1003 assert(function !=
1004 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1005 "post_event_flag mismatch");
1006
1007 // post the bind event, and possible change the bind function
1008 JvmtiExport::post_native_method_bind(this, &function);
1009 }
1010 *native_function = function;
1011 // This function can be called more than once. We must make sure that we always
1012 // use the latest registered method -> check if a stub already has been generated.
1013 // If so, we have to make it not_entrant.
1014 nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
1015 if (nm != nullptr) {
1016 nm->make_not_entrant();
1017 }
1018 }
1019
1020
1021 bool Method::has_native_function() const {
1022 if (is_special_native_intrinsic())
1023 return false; // special-cased in SharedRuntime::generate_native_wrapper
1024 address func = native_function();
1025 return (func != nullptr && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
1026 }
1027
1028
1029 void Method::clear_native_function() {
1030 // Note: is_method_handle_intrinsic() is allowed here.
1031 set_native_function(
1032 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1033 !native_bind_event_is_interesting);
1034 this->unlink_code();
1035 }
1036
1037
1038 void Method::set_signature_handler(address handler) {
1039 address* signature_handler = signature_handler_addr();
1040 *signature_handler = handler;
1041 }
1042
1043
1044 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
1045 assert(reason != nullptr, "must provide a reason");
1046 if (PrintCompilation && report) {
1047 ttyLocker ttyl;
1048 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
1049 if (comp_level == CompLevel_all) {
1050 tty->print("all levels ");
1051 } else {
1052 tty->print("level %d ", comp_level);
1053 }
1054 this->print_short_name(tty);
1055 int size = this->code_size();
1056 if (size > 0) {
1057 tty->print(" (%d bytes)", size);
1058 }
1059 if (reason != nullptr) {
1060 tty->print(" %s", reason);
1061 }
1062 tty->cr();
1063 }
1064 if ((TraceDeoptimization || LogCompilation) && (xtty != nullptr)) {
1065 ttyLocker ttyl;
1066 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
1067 os::current_thread_id(), is_osr, comp_level);
1068 if (reason != nullptr) {
1069 xtty->print(" reason=\'%s\'", reason);
1070 }
1071 xtty->method(this);
1072 xtty->stamp();
1073 xtty->end_elem();
1074 }
1075 }
1076
1077 bool Method::is_always_compilable() const {
1078 // Generated adapters must be compiled
1079 if (is_special_native_intrinsic() && is_synthetic()) {
1080 assert(!is_not_c1_compilable(), "sanity check");
1081 assert(!is_not_c2_compilable(), "sanity check");
1082 return true;
1083 }
1084
1085 return false;
1086 }
1087
1088 bool Method::is_not_compilable(int comp_level) const {
1089 if (number_of_breakpoints() > 0)
1090 return true;
1091 if (is_always_compilable())
1092 return false;
1093 if (comp_level == CompLevel_any)
1094 return is_not_c1_compilable() && is_not_c2_compilable();
1095 if (is_c1_compile(comp_level))
1096 return is_not_c1_compilable();
1097 if (is_c2_compile(comp_level))
1098 return is_not_c2_compilable();
1099 return false;
1100 }
1101
1102 // call this when compiler finds that this method is not compilable
1103 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
1104 if (is_always_compilable()) {
1105 // Don't mark a method which should be always compilable
1106 return;
1107 }
1108 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
1109 if (comp_level == CompLevel_all) {
1110 set_is_not_c1_compilable();
1111 set_is_not_c2_compilable();
1112 } else {
1113 if (is_c1_compile(comp_level))
1114 set_is_not_c1_compilable();
1115 if (is_c2_compile(comp_level))
1116 set_is_not_c2_compilable();
1117 }
1118 assert(!CompilationPolicy::can_be_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1119 }
1120
1121 bool Method::is_not_osr_compilable(int comp_level) const {
1122 if (is_not_compilable(comp_level))
1123 return true;
1124 if (comp_level == CompLevel_any)
1125 return is_not_c1_osr_compilable() && is_not_c2_osr_compilable();
1126 if (is_c1_compile(comp_level))
1127 return is_not_c1_osr_compilable();
1128 if (is_c2_compile(comp_level))
1129 return is_not_c2_osr_compilable();
1130 return false;
1131 }
1132
1133 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
1134 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
1135 if (comp_level == CompLevel_all) {
1136 set_is_not_c1_osr_compilable();
1137 set_is_not_c2_osr_compilable();
1138 } else {
1139 if (is_c1_compile(comp_level))
1140 set_is_not_c1_osr_compilable();
1141 if (is_c2_compile(comp_level))
1142 set_is_not_c2_osr_compilable();
1143 }
1144 assert(!CompilationPolicy::can_be_osr_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1145 }
1146
1147 // Revert to using the interpreter and clear out the nmethod
1148 void Method::clear_code() {
1149 // this may be null if c2i adapters have not been made yet
1150 // Only should happen at allocate time.
1151 if (adapter() == nullptr) {
1152 _from_compiled_entry = nullptr;
1153 } else {
1154 _from_compiled_entry = adapter()->get_c2i_entry();
1155 }
1156 OrderAccess::storestore();
1157 _from_interpreted_entry = _i2i_entry;
1158 OrderAccess::storestore();
1159 _code = nullptr;
1160 }
1161
1162 void Method::unlink_code(nmethod *compare) {
1163 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1164 // We need to check if either the _code or _from_compiled_code_entry_point
1165 // refer to this nmethod because there is a race in setting these two fields
1166 // in Method* as seen in bugid 4947125.
1167 if (code() == compare ||
1168 from_compiled_entry() == compare->verified_entry_point()) {
1169 clear_code();
1170 }
1171 }
1172
1173 void Method::unlink_code() {
1174 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1175 clear_code();
1176 }
1177
1178 #if INCLUDE_CDS
1179 // Called by class data sharing to remove any entry points (which are not shared)
1180 void Method::unlink_method() {
1181 assert(CDSConfig::is_dumping_archive(), "sanity");
1182 _code = nullptr;
1183 _adapter = nullptr;
1184 _i2i_entry = nullptr;
1185 _from_compiled_entry = nullptr;
1186 _from_interpreted_entry = nullptr;
1187
1188 if (is_native()) {
1189 *native_function_addr() = nullptr;
1190 set_signature_handler(nullptr);
1191 }
1192 NOT_PRODUCT(set_compiled_invocation_count(0);)
1193
1194 clear_method_data();
1195 clear_method_counters();
1196 remove_unshareable_flags();
1197 }
1198
1199 void Method::remove_unshareable_flags() {
1200 // clear all the flags that shouldn't be in the archived version
1201 assert(!is_old(), "must be");
1202 assert(!is_obsolete(), "must be");
1203 assert(!is_deleted(), "must be");
1204
1205 set_is_prefixed_native(false);
1206 set_queued_for_compilation(false);
1207 set_is_not_c2_compilable(false);
1208 set_is_not_c1_compilable(false);
1209 set_is_not_c2_osr_compilable(false);
1210 set_on_stack_flag(false);
1211 }
1212 #endif
1213
1214 // Called when the method_holder is getting linked. Setup entrypoints so the method
1215 // is ready to be called from interpreter, compiler, and vtables.
1216 void Method::link_method(const methodHandle& h_method, TRAPS) {
1217 // If the code cache is full, we may reenter this function for the
1218 // leftover methods that weren't linked.
1219 if (adapter() != nullptr) {
1220 return;
1221 }
1222 assert( _code == nullptr, "nothing compiled yet" );
1223
1224 // Setup interpreter entrypoint
1225 assert(this == h_method(), "wrong h_method()" );
1226
1227 assert(adapter() == nullptr, "init'd to null");
1228 address entry = Interpreter::entry_for_method(h_method);
1229 assert(entry != nullptr, "interpreter entry must be non-null");
1230 // Sets both _i2i_entry and _from_interpreted_entry
1231 set_interpreter_entry(entry);
1232
1233 // Don't overwrite already registered native entries.
1234 if (is_native() && !has_native_function()) {
1235 set_native_function(
1236 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1237 !native_bind_event_is_interesting);
1238 }
1239
1240 // Setup compiler entrypoint. This is made eagerly, so we do not need
1241 // special handling of vtables. An alternative is to make adapters more
1242 // lazily by calling make_adapter() from from_compiled_entry() for the
1243 // normal calls. For vtable calls life gets more complicated. When a
1244 // call-site goes mega-morphic we need adapters in all methods which can be
1245 // called from the vtable. We need adapters on such methods that get loaded
1246 // later. Ditto for mega-morphic itable calls. If this proves to be a
1247 // problem we'll make these lazily later.
1248 (void) make_adapters(h_method, CHECK);
1249
1250 // ONLY USE the h_method now as make_adapter may have blocked
1251
1252 if (h_method->is_continuation_native_intrinsic()) {
1253 _from_interpreted_entry = nullptr;
1254 _from_compiled_entry = nullptr;
1255 _i2i_entry = nullptr;
1256 if (Continuations::enabled()) {
1257 assert(!Threads::is_vm_complete(), "should only be called during vm init");
1258 AdapterHandlerLibrary::create_native_wrapper(h_method);
1259 if (!h_method->has_compiled_code()) {
1260 THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), "Initial size of CodeCache is too small");
1261 }
1262 assert(_from_interpreted_entry == get_i2c_entry(), "invariant");
1263 }
1264 }
1265 }
1266
1267 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1268 // Adapters for compiled code are made eagerly here. They are fairly
1269 // small (generally < 100 bytes) and quick to make (and cached and shared)
1270 // so making them eagerly shouldn't be too expensive.
1271 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1272 if (adapter == nullptr ) {
1273 if (!is_init_completed()) {
1274 // Don't throw exceptions during VM initialization because java.lang.* classes
1275 // might not have been initialized, causing problems when constructing the
1276 // Java exception object.
1277 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1278 } else {
1279 THROW_MSG_NULL(vmSymbols::java_lang_OutOfMemoryError(), "Out of space in CodeCache for adapters");
1280 }
1281 }
1282
1283 mh->set_adapter_entry(adapter);
1284 mh->_from_compiled_entry = adapter->get_c2i_entry();
1285 return adapter->get_c2i_entry();
1286 }
1287
1288 // The verified_code_entry() must be called when a invoke is resolved
1289 // on this method.
1290
1291 // It returns the compiled code entry point, after asserting not null.
1292 // This function is called after potential safepoints so that nmethod
1293 // or adapter that it points to is still live and valid.
1294 // This function must not hit a safepoint!
1295 address Method::verified_code_entry() {
1296 debug_only(NoSafepointVerifier nsv;)
1297 assert(_from_compiled_entry != nullptr, "must be set");
1298 return _from_compiled_entry;
1299 }
1300
1301 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1302 // (could be racing a deopt).
1303 // Not inline to avoid circular ref.
1304 bool Method::check_code() const {
1305 // cached in a register or local. There's a race on the value of the field.
1306 nmethod *code = Atomic::load_acquire(&_code);
1307 return code == nullptr || (code->method() == nullptr) || (code->method() == (Method*)this && !code->is_osr_method());
1308 }
1309
1310 // Install compiled code. Instantly it can execute.
1311 void Method::set_code(const methodHandle& mh, nmethod *code) {
1312 assert_lock_strong(NMethodState_lock);
1313 assert( code, "use clear_code to remove code" );
1314 assert( mh->check_code(), "" );
1315
1316 guarantee(mh->adapter() != nullptr, "Adapter blob must already exist!");
1317
1318 // These writes must happen in this order, because the interpreter will
1319 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1320 // which jumps to _from_compiled_entry.
1321 mh->_code = code; // Assign before allowing compiled code to exec
1322
1323 int comp_level = code->comp_level();
1324 // In theory there could be a race here. In practice it is unlikely
1325 // and not worth worrying about.
1326 if (comp_level > mh->highest_comp_level()) {
1327 mh->set_highest_comp_level(comp_level);
1328 }
1329
1330 OrderAccess::storestore();
1331 mh->_from_compiled_entry = code->verified_entry_point();
1332 OrderAccess::storestore();
1333
1334 if (mh->is_continuation_native_intrinsic()) {
1335 assert(mh->_from_interpreted_entry == nullptr, "initialized incorrectly"); // see link_method
1336
1337 if (mh->is_continuation_enter_intrinsic()) {
1338 // This is the entry used when we're in interpreter-only mode; see InterpreterMacroAssembler::jump_from_interpreted
1339 mh->_i2i_entry = ContinuationEntry::interpreted_entry();
1340 } else if (mh->is_continuation_yield_intrinsic()) {
1341 mh->_i2i_entry = mh->get_i2c_entry();
1342 } else {
1343 guarantee(false, "Unknown Continuation native intrinsic");
1344 }
1345 // This must come last, as it is what's tested in LinkResolver::resolve_static_call
1346 Atomic::release_store(&mh->_from_interpreted_entry , mh->get_i2c_entry());
1347 } else if (!mh->is_method_handle_intrinsic()) {
1348 // Instantly compiled code can execute.
1349 mh->_from_interpreted_entry = mh->get_i2c_entry();
1350 }
1351 }
1352
1353
1354 bool Method::is_overridden_in(Klass* k) const {
1355 InstanceKlass* ik = InstanceKlass::cast(k);
1356
1357 if (ik->is_interface()) return false;
1358
1359 // If method is an interface, we skip it - except if it
1360 // is a miranda method
1361 if (method_holder()->is_interface()) {
1362 // Check that method is not a miranda method
1363 if (ik->lookup_method(name(), signature()) == nullptr) {
1364 // No implementation exist - so miranda method
1365 return false;
1366 }
1367 return true;
1368 }
1369
1370 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1371 if (!has_vtable_index()) {
1372 return false;
1373 } else {
1374 Method* vt_m = ik->method_at_vtable(vtable_index());
1375 return vt_m != this;
1376 }
1377 }
1378
1379
1380 // give advice about whether this Method* should be cached or not
1381 bool Method::should_not_be_cached() const {
1382 if (is_old()) {
1383 // This method has been redefined. It is either EMCP or obsolete
1384 // and we don't want to cache it because that would pin the method
1385 // down and prevent it from being collectible if and when it
1386 // finishes executing.
1387 return true;
1388 }
1389
1390 // caching this method should be just fine
1391 return false;
1392 }
1393
1394
1395 /**
1396 * Returns true if this is one of the specially treated methods for
1397 * security related stack walks (like Reflection.getCallerClass).
1398 */
1399 bool Method::is_ignored_by_security_stack_walk() const {
1400 if (intrinsic_id() == vmIntrinsics::_invoke) {
1401 // This is Method.invoke() -- ignore it
1402 return true;
1403 }
1404 if (method_holder()->is_subclass_of(vmClasses::reflect_MethodAccessorImpl_klass())) {
1405 // This is an auxiliary frame -- ignore it
1406 return true;
1407 }
1408 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1409 // This is an internal adapter frame for method handles -- ignore it
1410 return true;
1411 }
1412 return false;
1413 }
1414
1415
1416 // Constant pool structure for invoke methods:
1417 enum {
1418 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1419 _imcp_invoke_signature, // utf8: (variable Symbol*)
1420 _imcp_limit
1421 };
1422
1423 // Test if this method is an MH adapter frame generated by Java code.
1424 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1425 bool Method::is_compiled_lambda_form() const {
1426 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1427 }
1428
1429 // Test if this method is an internal MH primitive method.
1430 bool Method::is_method_handle_intrinsic() const {
1431 vmIntrinsics::ID iid = intrinsic_id();
1432 return (MethodHandles::is_signature_polymorphic(iid) &&
1433 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1434 }
1435
1436 bool Method::has_member_arg() const {
1437 vmIntrinsics::ID iid = intrinsic_id();
1438 return (MethodHandles::is_signature_polymorphic(iid) &&
1439 MethodHandles::has_member_arg(iid));
1440 }
1441
1442 // Make an instance of a signature-polymorphic internal MH primitive.
1443 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1444 Symbol* signature,
1445 TRAPS) {
1446 ResourceMark rm(THREAD);
1447 methodHandle empty;
1448
1449 InstanceKlass* holder = vmClasses::MethodHandle_klass();
1450 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1451 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1452
1453 log_info(methodhandles)("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1454
1455 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1456 name->increment_refcount();
1457 signature->increment_refcount();
1458
1459 int cp_length = _imcp_limit;
1460 ClassLoaderData* loader_data = holder->class_loader_data();
1461 constantPoolHandle cp;
1462 {
1463 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1464 cp = constantPoolHandle(THREAD, cp_oop);
1465 }
1466 cp->copy_fields(holder->constants());
1467 cp->set_pool_holder(holder);
1468 cp->symbol_at_put(_imcp_invoke_name, name);
1469 cp->symbol_at_put(_imcp_invoke_signature, signature);
1470 cp->set_has_preresolution();
1471
1472 // decide on access bits: public or not?
1473 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1474 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1475 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1476 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1477
1478 methodHandle m;
1479 {
1480 InlineTableSizes sizes;
1481 Method* m_oop = Method::allocate(loader_data, 0,
1482 accessFlags_from(flags_bits), &sizes,
1483 ConstMethod::NORMAL,
1484 name,
1485 CHECK_(empty));
1486 m = methodHandle(THREAD, m_oop);
1487 }
1488 m->set_constants(cp());
1489 m->set_name_index(_imcp_invoke_name);
1490 m->set_signature_index(_imcp_invoke_signature);
1491 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1492 assert(m->signature() == signature, "");
1493 m->constMethod()->compute_from_signature(signature, must_be_static);
1494 m->init_intrinsic_id(klass_id_for_intrinsics(m->method_holder()));
1495 assert(m->is_method_handle_intrinsic(), "");
1496 #ifdef ASSERT
1497 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1498 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1499 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1500 #endif //ASSERT
1501
1502 // Finally, set up its entry points.
1503 assert(m->can_be_statically_bound(), "");
1504 m->set_vtable_index(Method::nonvirtual_vtable_index);
1505 m->link_method(m, CHECK_(empty));
1506
1507 if (iid == vmIntrinsics::_linkToNative) {
1508 m->set_interpreter_entry(m->adapter()->get_i2c_entry());
1509 }
1510 if (log_is_enabled(Debug, methodhandles)) {
1511 LogTarget(Debug, methodhandles) lt;
1512 LogStream ls(lt);
1513 m->print_on(&ls);
1514 }
1515
1516 return m;
1517 }
1518
1519 Klass* Method::check_non_bcp_klass(Klass* klass) {
1520 if (klass != nullptr && klass->class_loader() != nullptr) {
1521 if (klass->is_objArray_klass())
1522 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1523 return klass;
1524 }
1525 return nullptr;
1526 }
1527
1528
1529 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1530 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1531 // Code below does not work for native methods - they should never get rewritten anyway
1532 assert(!m->is_native(), "cannot rewrite native methods");
1533 // Allocate new Method*
1534 AccessFlags flags = m->access_flags();
1535
1536 ConstMethod* cm = m->constMethod();
1537 int checked_exceptions_len = cm->checked_exceptions_length();
1538 int localvariable_len = cm->localvariable_table_length();
1539 int exception_table_len = cm->exception_table_length();
1540 int method_parameters_len = cm->method_parameters_length();
1541 int method_annotations_len = cm->method_annotations_length();
1542 int parameter_annotations_len = cm->parameter_annotations_length();
1543 int type_annotations_len = cm->type_annotations_length();
1544 int default_annotations_len = cm->default_annotations_length();
1545
1546 InlineTableSizes sizes(
1547 localvariable_len,
1548 new_compressed_linenumber_size,
1549 exception_table_len,
1550 checked_exceptions_len,
1551 method_parameters_len,
1552 cm->generic_signature_index(),
1553 method_annotations_len,
1554 parameter_annotations_len,
1555 type_annotations_len,
1556 default_annotations_len,
1557 0);
1558
1559 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1560 Method* newm_oop = Method::allocate(loader_data,
1561 new_code_length,
1562 flags,
1563 &sizes,
1564 m->method_type(),
1565 m->name(),
1566 CHECK_(methodHandle()));
1567 methodHandle newm (THREAD, newm_oop);
1568
1569 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1570 ConstMethod* newcm = newm->constMethod();
1571 int new_const_method_size = newm->constMethod()->size();
1572
1573 // This works because the source and target are both Methods. Some compilers
1574 // (e.g., clang) complain that the target vtable pointer will be stomped,
1575 // so cast away newm()'s and m()'s Methodness.
1576 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1577
1578 // Create shallow copy of ConstMethod.
1579 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1580
1581 // Reset correct method/const method, method size, and parameter info
1582 newm->set_constMethod(newcm);
1583 newm->constMethod()->set_code_size(new_code_length);
1584 newm->constMethod()->set_constMethod_size(new_const_method_size);
1585 assert(newm->code_size() == new_code_length, "check");
1586 assert(newm->method_parameters_length() == method_parameters_len, "check");
1587 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1588 assert(newm->exception_table_length() == exception_table_len, "check");
1589 assert(newm->localvariable_table_length() == localvariable_len, "check");
1590 // Copy new byte codes
1591 memcpy(newm->code_base(), new_code, new_code_length);
1592 // Copy line number table
1593 if (new_compressed_linenumber_size > 0) {
1594 memcpy(newm->compressed_linenumber_table(),
1595 new_compressed_linenumber_table,
1596 new_compressed_linenumber_size);
1597 }
1598 // Copy method_parameters
1599 if (method_parameters_len > 0) {
1600 memcpy(newm->method_parameters_start(),
1601 m->method_parameters_start(),
1602 method_parameters_len * sizeof(MethodParametersElement));
1603 }
1604 // Copy checked_exceptions
1605 if (checked_exceptions_len > 0) {
1606 memcpy(newm->checked_exceptions_start(),
1607 m->checked_exceptions_start(),
1608 checked_exceptions_len * sizeof(CheckedExceptionElement));
1609 }
1610 // Copy exception table
1611 if (exception_table_len > 0) {
1612 memcpy(newm->exception_table_start(),
1613 m->exception_table_start(),
1614 exception_table_len * sizeof(ExceptionTableElement));
1615 }
1616 // Copy local variable number table
1617 if (localvariable_len > 0) {
1618 memcpy(newm->localvariable_table_start(),
1619 m->localvariable_table_start(),
1620 localvariable_len * sizeof(LocalVariableTableElement));
1621 }
1622 // Copy stackmap table
1623 if (m->has_stackmap_table()) {
1624 int code_attribute_length = m->stackmap_data()->length();
1625 Array<u1>* stackmap_data =
1626 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_(methodHandle()));
1627 memcpy((void*)stackmap_data->adr_at(0),
1628 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1629 newm->set_stackmap_data(stackmap_data);
1630 }
1631
1632 // copy annotations over to new method
1633 newcm->copy_annotations_from(loader_data, cm, CHECK_(methodHandle()));
1634 return newm;
1635 }
1636
1637 vmSymbolID Method::klass_id_for_intrinsics(const Klass* holder) {
1638 // if loader is not the default loader (i.e., non-null), we can't know the intrinsics
1639 // because we are not loading from core libraries
1640 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1641 // which does not use the class default class loader so we check for its loader here
1642 const InstanceKlass* ik = InstanceKlass::cast(holder);
1643 if ((ik->class_loader() != nullptr) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1644 return vmSymbolID::NO_SID; // regardless of name, no intrinsics here
1645 }
1646
1647 // see if the klass name is well-known:
1648 Symbol* klass_name = ik->name();
1649 vmSymbolID id = vmSymbols::find_sid(klass_name);
1650 if (id != vmSymbolID::NO_SID && vmIntrinsics::class_has_intrinsics(id)) {
1651 return id;
1652 } else {
1653 return vmSymbolID::NO_SID;
1654 }
1655 }
1656
1657 void Method::init_intrinsic_id(vmSymbolID klass_id) {
1658 assert(_intrinsic_id == static_cast<int>(vmIntrinsics::_none), "do this just once");
1659 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1660 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1661 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1662
1663 // the klass name is well-known:
1664 assert(klass_id == klass_id_for_intrinsics(method_holder()), "must be");
1665 assert(klass_id != vmSymbolID::NO_SID, "caller responsibility");
1666
1667 // ditto for method and signature:
1668 vmSymbolID name_id = vmSymbols::find_sid(name());
1669 if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1670 && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1671 && name_id == vmSymbolID::NO_SID) {
1672 return;
1673 }
1674 vmSymbolID sig_id = vmSymbols::find_sid(signature());
1675 if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1676 && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1677 && sig_id == vmSymbolID::NO_SID) {
1678 return;
1679 }
1680 jshort flags = access_flags().as_short();
1681
1682 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1683 if (id != vmIntrinsics::_none) {
1684 set_intrinsic_id(id);
1685 if (id == vmIntrinsics::_Class_cast) {
1686 // Even if the intrinsic is rejected, we want to inline this simple method.
1687 set_force_inline();
1688 }
1689 return;
1690 }
1691
1692 // A few slightly irregular cases:
1693 switch (klass_id) {
1694 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1695 case VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1696 case VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1697 if (!is_native()) break;
1698 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1699 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1700 id = vmIntrinsics::_none;
1701 break;
1702
1703 default:
1704 break;
1705 }
1706
1707 if (id != vmIntrinsics::_none) {
1708 // Set up its iid. It is an alias method.
1709 set_intrinsic_id(id);
1710 return;
1711 }
1712 }
1713
1714 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1715 if (!THREAD->can_call_java()) {
1716 // There is nothing useful this routine can do from within the Compile thread.
1717 // Hopefully, the signature contains only well-known classes.
1718 // We could scan for this and return true/false, but the caller won't care.
1719 return false;
1720 }
1721 bool sig_is_loaded = true;
1722 ResourceMark rm(THREAD);
1723 for (ResolvingSignatureStream ss(m()); !ss.is_done(); ss.next()) {
1724 if (ss.is_reference()) {
1725 // load everything, including arrays "[Lfoo;"
1726 Klass* klass = ss.as_klass(SignatureStream::ReturnNull, THREAD);
1727 // We are loading classes eagerly. If a ClassNotFoundException or
1728 // a LinkageError was generated, be sure to ignore it.
1729 if (HAS_PENDING_EXCEPTION) {
1730 if (PENDING_EXCEPTION->is_a(vmClasses::ClassNotFoundException_klass()) ||
1731 PENDING_EXCEPTION->is_a(vmClasses::LinkageError_klass())) {
1732 CLEAR_PENDING_EXCEPTION;
1733 } else {
1734 return false;
1735 }
1736 }
1737 if( klass == nullptr) { sig_is_loaded = false; }
1738 }
1739 }
1740 return sig_is_loaded;
1741 }
1742
1743 // Exposed so field engineers can debug VM
1744 void Method::print_short_name(outputStream* st) const {
1745 ResourceMark rm;
1746 #ifdef PRODUCT
1747 st->print(" %s::", method_holder()->external_name());
1748 #else
1749 st->print(" %s::", method_holder()->internal_name());
1750 #endif
1751 name()->print_symbol_on(st);
1752 if (WizardMode) signature()->print_symbol_on(st);
1753 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1754 MethodHandles::print_as_basic_type_signature_on(st, signature());
1755 }
1756
1757 // Comparer for sorting an object array containing
1758 // Method*s.
1759 static int method_comparator(Method* a, Method* b) {
1760 return a->name()->fast_compare(b->name());
1761 }
1762
1763 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1764 // default_methods also uses this without the ordering for fast find_method
1765 void Method::sort_methods(Array<Method*>* methods, bool set_idnums, method_comparator_func func) {
1766 int length = methods->length();
1767 if (length > 1) {
1768 if (func == nullptr) {
1769 func = method_comparator;
1770 }
1771 {
1772 NoSafepointVerifier nsv;
1773 QuickSort::sort(methods->data(), length, func, /*idempotent=*/false);
1774 }
1775 // Reset method ordering
1776 if (set_idnums) {
1777 for (u2 i = 0; i < length; i++) {
1778 Method* m = methods->at(i);
1779 m->set_method_idnum(i);
1780 m->set_orig_method_idnum(i);
1781 }
1782 }
1783 }
1784 }
1785
1786 //-----------------------------------------------------------------------------------
1787 // Non-product code unless JVM/TI needs it
1788
1789 #if !defined(PRODUCT) || INCLUDE_JVMTI
1790 class SignatureTypePrinter : public SignatureTypeNames {
1791 private:
1792 outputStream* _st;
1793 bool _use_separator;
1794
1795 void type_name(const char* name) {
1796 if (_use_separator) _st->print(", ");
1797 _st->print("%s", name);
1798 _use_separator = true;
1799 }
1800
1801 public:
1802 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1803 _st = st;
1804 _use_separator = false;
1805 }
1806
1807 void print_parameters() { _use_separator = false; do_parameters_on(this); }
1808 void print_returntype() { _use_separator = false; do_type(return_type()); }
1809 };
1810
1811
1812 void Method::print_name(outputStream* st) const {
1813 Thread *thread = Thread::current();
1814 ResourceMark rm(thread);
1815 st->print("%s ", is_static() ? "static" : "virtual");
1816 if (WizardMode) {
1817 st->print("%s.", method_holder()->internal_name());
1818 name()->print_symbol_on(st);
1819 signature()->print_symbol_on(st);
1820 } else {
1821 SignatureTypePrinter sig(signature(), st);
1822 sig.print_returntype();
1823 st->print(" %s.", method_holder()->internal_name());
1824 name()->print_symbol_on(st);
1825 st->print("(");
1826 sig.print_parameters();
1827 st->print(")");
1828 }
1829 }
1830 #endif // !PRODUCT || INCLUDE_JVMTI
1831
1832
1833 void Method::print_codes_on(outputStream* st, int flags) const {
1834 print_codes_on(0, code_size(), st, flags);
1835 }
1836
1837 void Method::print_codes_on(int from, int to, outputStream* st, int flags) const {
1838 Thread *thread = Thread::current();
1839 ResourceMark rm(thread);
1840 methodHandle mh (thread, (Method*)this);
1841 BytecodeTracer::print_method_codes(mh, from, to, st, flags);
1842 }
1843
1844 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1845 _bci = 0;
1846 _line = 0;
1847 };
1848
1849 bool CompressedLineNumberReadStream::read_pair() {
1850 jubyte next = read_byte();
1851 // Check for terminator
1852 if (next == 0) return false;
1853 if (next == 0xFF) {
1854 // Escape character, regular compression used
1855 _bci += read_signed_int();
1856 _line += read_signed_int();
1857 } else {
1858 // Single byte compression used
1859 _bci += next >> 3;
1860 _line += next & 0x7;
1861 }
1862 return true;
1863 }
1864
1865 #if INCLUDE_JVMTI
1866
1867 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1868 BreakpointInfo* bp = method_holder()->breakpoints();
1869 for (; bp != nullptr; bp = bp->next()) {
1870 if (bp->match(this, bci)) {
1871 return bp->orig_bytecode();
1872 }
1873 }
1874 {
1875 ResourceMark rm;
1876 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1877 }
1878 return Bytecodes::_shouldnotreachhere;
1879 }
1880
1881 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1882 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1883 BreakpointInfo* bp = method_holder()->breakpoints();
1884 for (; bp != nullptr; bp = bp->next()) {
1885 if (bp->match(this, bci)) {
1886 bp->set_orig_bytecode(code);
1887 // and continue, in case there is more than one
1888 }
1889 }
1890 }
1891
1892 void Method::set_breakpoint(int bci) {
1893 InstanceKlass* ik = method_holder();
1894 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1895 bp->set_next(ik->breakpoints());
1896 ik->set_breakpoints(bp);
1897 // do this last:
1898 bp->set(this);
1899 }
1900
1901 static void clear_matches(Method* m, int bci) {
1902 InstanceKlass* ik = m->method_holder();
1903 BreakpointInfo* prev_bp = nullptr;
1904 BreakpointInfo* next_bp;
1905 for (BreakpointInfo* bp = ik->breakpoints(); bp != nullptr; bp = next_bp) {
1906 next_bp = bp->next();
1907 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1908 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1909 // do this first:
1910 bp->clear(m);
1911 // unhook it
1912 if (prev_bp != nullptr)
1913 prev_bp->set_next(next_bp);
1914 else
1915 ik->set_breakpoints(next_bp);
1916 delete bp;
1917 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1918 // at same location. So we have multiple matching (method_index and bci)
1919 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1920 // breakpoint for clear_breakpoint request and keep all other method versions
1921 // BreakpointInfo for future clear_breakpoint request.
1922 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1923 // which is being called when class is unloaded. We delete all the Breakpoint
1924 // information for all versions of method. We may not correctly restore the original
1925 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1926 // so these methods won't be used anymore.
1927 if (bci >= 0) {
1928 break;
1929 }
1930 } else {
1931 // This one is a keeper.
1932 prev_bp = bp;
1933 }
1934 }
1935 }
1936
1937 void Method::clear_breakpoint(int bci) {
1938 assert(bci >= 0, "");
1939 clear_matches(this, bci);
1940 }
1941
1942 void Method::clear_all_breakpoints() {
1943 clear_matches(this, -1);
1944 }
1945
1946 #endif // INCLUDE_JVMTI
1947
1948 int Method::invocation_count() const {
1949 MethodCounters* mcs = method_counters();
1950 MethodData* mdo = method_data();
1951 if (((mcs != nullptr) ? mcs->invocation_counter()->carry() : false) ||
1952 ((mdo != nullptr) ? mdo->invocation_counter()->carry() : false)) {
1953 return InvocationCounter::count_limit;
1954 } else {
1955 return ((mcs != nullptr) ? mcs->invocation_counter()->count() : 0) +
1956 ((mdo != nullptr) ? mdo->invocation_counter()->count() : 0);
1957 }
1958 }
1959
1960 int Method::backedge_count() const {
1961 MethodCounters* mcs = method_counters();
1962 MethodData* mdo = method_data();
1963 if (((mcs != nullptr) ? mcs->backedge_counter()->carry() : false) ||
1964 ((mdo != nullptr) ? mdo->backedge_counter()->carry() : false)) {
1965 return InvocationCounter::count_limit;
1966 } else {
1967 return ((mcs != nullptr) ? mcs->backedge_counter()->count() : 0) +
1968 ((mdo != nullptr) ? mdo->backedge_counter()->count() : 0);
1969 }
1970 }
1971
1972 int Method::highest_comp_level() const {
1973 const MethodCounters* mcs = method_counters();
1974 if (mcs != nullptr) {
1975 return mcs->highest_comp_level();
1976 } else {
1977 return CompLevel_none;
1978 }
1979 }
1980
1981 int Method::highest_osr_comp_level() const {
1982 const MethodCounters* mcs = method_counters();
1983 if (mcs != nullptr) {
1984 return mcs->highest_osr_comp_level();
1985 } else {
1986 return CompLevel_none;
1987 }
1988 }
1989
1990 void Method::set_highest_comp_level(int level) {
1991 MethodCounters* mcs = method_counters();
1992 if (mcs != nullptr) {
1993 mcs->set_highest_comp_level(level);
1994 }
1995 }
1996
1997 void Method::set_highest_osr_comp_level(int level) {
1998 MethodCounters* mcs = method_counters();
1999 if (mcs != nullptr) {
2000 mcs->set_highest_osr_comp_level(level);
2001 }
2002 }
2003
2004 #if INCLUDE_JVMTI
2005
2006 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
2007 _bci = bci;
2008 _name_index = m->name_index();
2009 _signature_index = m->signature_index();
2010 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
2011 if (_orig_bytecode == Bytecodes::_breakpoint)
2012 _orig_bytecode = m->orig_bytecode_at(_bci);
2013 _next = nullptr;
2014 }
2015
2016 void BreakpointInfo::set(Method* method) {
2017 #ifdef ASSERT
2018 {
2019 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
2020 if (code == Bytecodes::_breakpoint)
2021 code = method->orig_bytecode_at(_bci);
2022 assert(orig_bytecode() == code, "original bytecode must be the same");
2023 }
2024 #endif
2025 Thread *thread = Thread::current();
2026 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2027 method->incr_number_of_breakpoints(thread);
2028 {
2029 // Deoptimize all dependents on this method
2030 HandleMark hm(thread);
2031 methodHandle mh(thread, method);
2032 CodeCache::mark_dependents_on_method_for_breakpoint(mh);
2033 }
2034 }
2035
2036 void BreakpointInfo::clear(Method* method) {
2037 *method->bcp_from(_bci) = orig_bytecode();
2038 assert(method->number_of_breakpoints() > 0, "must not go negative");
2039 method->decr_number_of_breakpoints(Thread::current());
2040 }
2041
2042 #endif // INCLUDE_JVMTI
2043
2044 // jmethodID handling
2045
2046 // This is a block allocating object, sort of like JNIHandleBlock, only a
2047 // lot simpler.
2048 // It's allocated on the CHeap because once we allocate a jmethodID, we can
2049 // never get rid of it.
2050
2051 static const int min_block_size = 8;
2052
2053 class JNIMethodBlockNode : public CHeapObj<mtClass> {
2054 friend class JNIMethodBlock;
2055 Method** _methods;
2056 int _number_of_methods;
2057 int _top;
2058 JNIMethodBlockNode* _next;
2059
2060 public:
2061
2062 JNIMethodBlockNode(int num_methods = min_block_size);
2063
2064 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
2065
2066 void ensure_methods(int num_addl_methods) {
2067 if (_top < _number_of_methods) {
2068 num_addl_methods -= _number_of_methods - _top;
2069 if (num_addl_methods <= 0) {
2070 return;
2071 }
2072 }
2073 if (_next == nullptr) {
2074 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
2075 } else {
2076 _next->ensure_methods(num_addl_methods);
2077 }
2078 }
2079 };
2080
2081 class JNIMethodBlock : public CHeapObj<mtClass> {
2082 JNIMethodBlockNode _head;
2083 JNIMethodBlockNode *_last_free;
2084 public:
2085 static Method* const _free_method;
2086
2087 JNIMethodBlock(int initial_capacity = min_block_size)
2088 : _head(initial_capacity), _last_free(&_head) {}
2089
2090 void ensure_methods(int num_addl_methods) {
2091 _last_free->ensure_methods(num_addl_methods);
2092 }
2093
2094 Method** add_method(Method* m) {
2095 for (JNIMethodBlockNode* b = _last_free; b != nullptr; b = b->_next) {
2096 if (b->_top < b->_number_of_methods) {
2097 // top points to the next free entry.
2098 int i = b->_top;
2099 b->_methods[i] = m;
2100 b->_top++;
2101 _last_free = b;
2102 return &(b->_methods[i]);
2103 } else if (b->_top == b->_number_of_methods) {
2104 // if the next free entry ran off the block see if there's a free entry
2105 for (int i = 0; i < b->_number_of_methods; i++) {
2106 if (b->_methods[i] == _free_method) {
2107 b->_methods[i] = m;
2108 _last_free = b;
2109 return &(b->_methods[i]);
2110 }
2111 }
2112 // Only check each block once for frees. They're very unlikely.
2113 // Increment top past the end of the block.
2114 b->_top++;
2115 }
2116 // need to allocate a next block.
2117 if (b->_next == nullptr) {
2118 b->_next = _last_free = new JNIMethodBlockNode();
2119 }
2120 }
2121 guarantee(false, "Should always allocate a free block");
2122 return nullptr;
2123 }
2124
2125 bool contains(Method** m) {
2126 if (m == nullptr) return false;
2127 for (JNIMethodBlockNode* b = &_head; b != nullptr; b = b->_next) {
2128 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2129 // This is a bit of extra checking, for two reasons. One is
2130 // that contains() deals with pointers that are passed in by
2131 // JNI code, so making sure that the pointer is aligned
2132 // correctly is valuable. The other is that <= and > are
2133 // technically not defined on pointers, so the if guard can
2134 // pass spuriously; no modern compiler is likely to make that
2135 // a problem, though (and if one did, the guard could also
2136 // fail spuriously, which would be bad).
2137 ptrdiff_t idx = m - b->_methods;
2138 if (b->_methods + idx == m) {
2139 return true;
2140 }
2141 }
2142 }
2143 return false; // not found
2144 }
2145
2146 // During class unloading the methods are cleared, which is different
2147 // than freed.
2148 void clear_all_methods() {
2149 for (JNIMethodBlockNode* b = &_head; b != nullptr; b = b->_next) {
2150 for (int i = 0; i< b->_number_of_methods; i++) {
2151 b->_methods[i] = nullptr;
2152 }
2153 }
2154 }
2155 #ifndef PRODUCT
2156 int count_methods() {
2157 // count all allocated methods
2158 int count = 0;
2159 for (JNIMethodBlockNode* b = &_head; b != nullptr; b = b->_next) {
2160 for (int i = 0; i< b->_number_of_methods; i++) {
2161 if (b->_methods[i] != _free_method) count++;
2162 }
2163 }
2164 return count;
2165 }
2166 #endif // PRODUCT
2167 };
2168
2169 // Something that can't be mistaken for an address or a markWord
2170 Method* const JNIMethodBlock::_free_method = (Method*)55;
2171
2172 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(nullptr) {
2173 _number_of_methods = MAX2(num_methods, min_block_size);
2174 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2175 for (int i = 0; i < _number_of_methods; i++) {
2176 _methods[i] = JNIMethodBlock::_free_method;
2177 }
2178 }
2179
2180 void Method::ensure_jmethod_ids(ClassLoaderData* cld, int capacity) {
2181 // Have to add jmethod_ids() to class loader data thread-safely.
2182 // Also have to add the method to the list safely, which the lock
2183 // protects as well.
2184 MutexLocker ml(JmethodIdCreation_lock, Mutex::_no_safepoint_check_flag);
2185 if (cld->jmethod_ids() == nullptr) {
2186 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2187 } else {
2188 cld->jmethod_ids()->ensure_methods(capacity);
2189 }
2190 }
2191
2192 // Add a method id to the jmethod_ids
2193 jmethodID Method::make_jmethod_id(ClassLoaderData* cld, Method* m) {
2194 // Have to add jmethod_ids() to class loader data thread-safely.
2195 // Also have to add the method to the list safely, which the lock
2196 // protects as well.
2197 assert(JmethodIdCreation_lock->owned_by_self(), "sanity check");
2198
2199 ResourceMark rm;
2200 log_debug(jmethod)("Creating jmethodID for Method %s", m->external_name());
2201 if (cld->jmethod_ids() == nullptr) {
2202 cld->set_jmethod_ids(new JNIMethodBlock());
2203 }
2204 // jmethodID is a pointer to Method*
2205 return (jmethodID)cld->jmethod_ids()->add_method(m);
2206 }
2207
2208 jmethodID Method::jmethod_id() {
2209 methodHandle mh(Thread::current(), this);
2210 return method_holder()->get_jmethod_id(mh);
2211 }
2212
2213 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2214 // Can't assert the method_holder is the same because the new method has the
2215 // scratch method holder.
2216 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2217 == new_method->method_holder()->class_loader() ||
2218 new_method->method_holder()->class_loader() == nullptr, // allow Unsafe substitution
2219 "changing to a different class loader");
2220 // Just change the method in place, jmethodID pointer doesn't change.
2221 *((Method**)jmid) = new_method;
2222 }
2223
2224 bool Method::is_method_id(jmethodID mid) {
2225 Method* m = resolve_jmethod_id(mid);
2226 assert(m != nullptr, "should be called with non-null method");
2227 InstanceKlass* ik = m->method_holder();
2228 ClassLoaderData* cld = ik->class_loader_data();
2229 if (cld->jmethod_ids() == nullptr) return false;
2230 return (cld->jmethod_ids()->contains((Method**)mid));
2231 }
2232
2233 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2234 if (mid == nullptr) return nullptr;
2235 Method* o = resolve_jmethod_id(mid);
2236 if (o == nullptr || o == JNIMethodBlock::_free_method) {
2237 return nullptr;
2238 }
2239 // Method should otherwise be valid. Assert for testing.
2240 assert(is_valid_method(o), "should be valid jmethodid");
2241 // If the method's class holder object is unreferenced, but not yet marked as
2242 // unloaded, we need to return null here too because after a safepoint, its memory
2243 // will be reclaimed.
2244 return o->method_holder()->is_loader_alive() ? o : nullptr;
2245 };
2246
2247 void Method::set_on_stack(const bool value) {
2248 // Set both the method itself and its constant pool. The constant pool
2249 // on stack means some method referring to it is also on the stack.
2250 constants()->set_on_stack(value);
2251
2252 bool already_set = on_stack_flag();
2253 set_on_stack_flag(value);
2254 if (value && !already_set) {
2255 MetadataOnStackMark::record(this);
2256 }
2257 }
2258
2259 void Method::record_gc_epoch() {
2260 // If any method is on the stack in continuations, none of them can be reclaimed,
2261 // so save the marking cycle to check for the whole class in the cpCache.
2262 // The cpCache is writeable.
2263 constants()->cache()->record_gc_epoch();
2264 }
2265
2266 // Called when the class loader is unloaded to make all methods weak.
2267 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2268 loader_data->jmethod_ids()->clear_all_methods();
2269 }
2270
2271 void Method::clear_jmethod_id() {
2272 // Being at a safepoint prevents racing against other class redefinitions
2273 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
2274 // The jmethodID is not stored in the Method instance, we need to look it up first
2275 jmethodID methodid = find_jmethod_id_or_null();
2276 // We need to make sure that jmethodID actually resolves to this method
2277 // - multiple redefined versions may share jmethodID slots and if a method
2278 // has already been rewired to a newer version we could be removing reference
2279 // to a still existing method instance
2280 if (methodid != nullptr && *((Method**)methodid) == this) {
2281 *((Method**)methodid) = nullptr;
2282 }
2283 }
2284
2285 bool Method::has_method_vptr(const void* ptr) {
2286 Method m;
2287 // This assumes that the vtbl pointer is the first word of a C++ object.
2288 return dereference_vptr(&m) == dereference_vptr(ptr);
2289 }
2290
2291 // Check that this pointer is valid by checking that the vtbl pointer matches
2292 bool Method::is_valid_method(const Method* m) {
2293 if (m == nullptr) {
2294 return false;
2295 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2296 // Quick sanity check on pointer.
2297 return false;
2298 } else if (!os::is_readable_range(m, m + 1)) {
2299 return false;
2300 } else if (m->is_shared()) {
2301 return CppVtables::is_valid_shared_method(m);
2302 } else if (Metaspace::contains_non_shared(m)) {
2303 return has_method_vptr((const void*)m);
2304 } else {
2305 return false;
2306 }
2307 }
2308
2309 #ifndef PRODUCT
2310 void Method::print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) {
2311 out->print("%d", loader_data->jmethod_ids()->count_methods());
2312 }
2313 #endif // PRODUCT
2314
2315
2316 // Printing
2317
2318 #ifndef PRODUCT
2319
2320 void Method::print_on(outputStream* st) const {
2321 ResourceMark rm;
2322 assert(is_method(), "must be method");
2323 st->print_cr("%s", internal_name());
2324 st->print_cr(" - this oop: " PTR_FORMAT, p2i(this));
2325 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2326 st->print (" - constants: " PTR_FORMAT " ", p2i(constants()));
2327 constants()->print_value_on(st); st->cr();
2328 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2329 st->print (" - flags: 0x%x ", _flags.as_int()); _flags.print_on(st); st->cr();
2330 st->print (" - name: "); name()->print_value_on(st); st->cr();
2331 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2332 st->print_cr(" - max stack: %d", max_stack());
2333 st->print_cr(" - max locals: %d", max_locals());
2334 st->print_cr(" - size of params: %d", size_of_parameters());
2335 st->print_cr(" - method size: %d", method_size());
2336 if (intrinsic_id() != vmIntrinsics::_none)
2337 st->print_cr(" - intrinsic id: %d %s", vmIntrinsics::as_int(intrinsic_id()), vmIntrinsics::name_at(intrinsic_id()));
2338 if (highest_comp_level() != CompLevel_none)
2339 st->print_cr(" - highest level: %d", highest_comp_level());
2340 st->print_cr(" - vtable index: %d", _vtable_index);
2341 st->print_cr(" - i2i entry: " PTR_FORMAT, p2i(interpreter_entry()));
2342 st->print( " - adapters: ");
2343 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2344 if (a == nullptr)
2345 st->print_cr(PTR_FORMAT, p2i(a));
2346 else
2347 a->print_adapter_on(st);
2348 st->print_cr(" - compiled entry " PTR_FORMAT, p2i(from_compiled_entry()));
2349 st->print_cr(" - code size: %d", code_size());
2350 if (code_size() != 0) {
2351 st->print_cr(" - code start: " PTR_FORMAT, p2i(code_base()));
2352 st->print_cr(" - code end (excl): " PTR_FORMAT, p2i(code_base() + code_size()));
2353 }
2354 if (method_data() != nullptr) {
2355 st->print_cr(" - method data: " PTR_FORMAT, p2i(method_data()));
2356 }
2357 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2358 if (checked_exceptions_length() > 0) {
2359 CheckedExceptionElement* table = checked_exceptions_start();
2360 st->print_cr(" - checked ex start: " PTR_FORMAT, p2i(table));
2361 if (Verbose) {
2362 for (int i = 0; i < checked_exceptions_length(); i++) {
2363 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2364 }
2365 }
2366 }
2367 if (has_linenumber_table()) {
2368 u_char* table = compressed_linenumber_table();
2369 st->print_cr(" - linenumber start: " PTR_FORMAT, p2i(table));
2370 if (Verbose) {
2371 CompressedLineNumberReadStream stream(table);
2372 while (stream.read_pair()) {
2373 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2374 }
2375 }
2376 }
2377 st->print_cr(" - localvar length: %d", localvariable_table_length());
2378 if (localvariable_table_length() > 0) {
2379 LocalVariableTableElement* table = localvariable_table_start();
2380 st->print_cr(" - localvar start: " PTR_FORMAT, p2i(table));
2381 if (Verbose) {
2382 for (int i = 0; i < localvariable_table_length(); i++) {
2383 int bci = table[i].start_bci;
2384 int len = table[i].length;
2385 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2386 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2387 int slot = table[i].slot;
2388 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2389 }
2390 }
2391 }
2392 if (code() != nullptr) {
2393 st->print (" - compiled code: ");
2394 code()->print_value_on(st);
2395 }
2396 if (is_native()) {
2397 st->print_cr(" - native function: " PTR_FORMAT, p2i(native_function()));
2398 st->print_cr(" - signature handler: " PTR_FORMAT, p2i(signature_handler()));
2399 }
2400 }
2401
2402 void Method::print_linkage_flags(outputStream* st) {
2403 access_flags().print_on(st);
2404 if (is_default_method()) {
2405 st->print("default ");
2406 }
2407 if (is_overpass()) {
2408 st->print("overpass ");
2409 }
2410 }
2411 #endif //PRODUCT
2412
2413 void Method::print_value_on(outputStream* st) const {
2414 assert(is_method(), "must be method");
2415 st->print("%s", internal_name());
2416 print_address_on(st);
2417 st->print(" ");
2418 name()->print_value_on(st);
2419 st->print(" ");
2420 signature()->print_value_on(st);
2421 st->print(" in ");
2422 method_holder()->print_value_on(st);
2423 if (WizardMode) st->print("#%d", _vtable_index);
2424 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2425 if (WizardMode && code() != nullptr) st->print(" ((nmethod*)%p)", code());
2426 }
2427
2428 // Verification
2429
2430 void Method::verify_on(outputStream* st) {
2431 guarantee(is_method(), "object must be method");
2432 guarantee(constants()->is_constantPool(), "should be constant pool");
2433 MethodData* md = method_data();
2434 guarantee(md == nullptr ||
2435 md->is_methodData(), "should be method data");
2436 }