1 /*
2 * Copyright (c) 1997, 2025, 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 "cds/aotMetaspace.hpp"
26 #include "cds/cdsConfig.hpp"
27 #include "cds/cppVtables.hpp"
28 #include "classfile/classLoader.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/aotCodeCache.hpp"
35 #include "code/codeCache.hpp"
36 #include "code/debugInfoRec.hpp"
37 #include "compiler/compilationPolicy.hpp"
38 #include "gc/shared/collectedHeap.inline.hpp"
39 #include "interpreter/bytecodes.hpp"
40 #include "interpreter/bytecodeStream.hpp"
41 #include "interpreter/bytecodeTracer.hpp"
42 #include "interpreter/interpreter.hpp"
43 #include "interpreter/oopMapCache.hpp"
44 #include "logging/log.hpp"
45 #include "logging/logStream.hpp"
46 #include "logging/logTag.hpp"
47 #include "memory/allocation.inline.hpp"
48 #include "memory/metadataFactory.hpp"
49 #include "memory/metaspaceClosure.hpp"
50 #include "memory/oopFactory.hpp"
51 #include "memory/resourceArea.hpp"
52 #include "memory/universe.hpp"
53 #include "nmt/memTracker.hpp"
54 #include "oops/constantPool.hpp"
55 #include "oops/constMethod.hpp"
56 #include "oops/jmethodIDTable.hpp"
57 #include "oops/klass.inline.hpp"
58 #include "oops/method.inline.hpp"
59 #include "oops/methodData.hpp"
60 #include "oops/objArrayKlass.hpp"
61 #include "oops/objArrayOop.inline.hpp"
62 #include "oops/oop.inline.hpp"
63 #include "oops/symbol.hpp"
64 #include "oops/trainingData.hpp"
65 #include "prims/jvmtiExport.hpp"
66 #include "prims/methodHandles.hpp"
67 #include "runtime/arguments.hpp"
68 #include "runtime/atomicAccess.hpp"
69 #include "runtime/continuationEntry.hpp"
70 #include "runtime/frame.inline.hpp"
71 #include "runtime/handles.inline.hpp"
72 #include "runtime/init.hpp"
73 #include "runtime/java.hpp"
74 #include "runtime/orderAccess.hpp"
75 #include "runtime/perfData.hpp"
76 #include "runtime/relocator.hpp"
77 #include "runtime/safepointVerifiers.hpp"
78 #include "runtime/sharedRuntime.hpp"
79 #include "runtime/signature.hpp"
80 #include "runtime/threads.hpp"
81 #include "runtime/vm_version.hpp"
82 #include "utilities/align.hpp"
83 #include "utilities/quickSort.hpp"
84 #include "utilities/vmError.hpp"
85 #include "utilities/xmlstream.hpp"
86
87 // Implementation of Method
88
89 Method* Method::allocate(ClassLoaderData* loader_data,
90 int byte_code_size,
91 AccessFlags access_flags,
92 InlineTableSizes* sizes,
93 ConstMethod::MethodType method_type,
94 Symbol* name,
95 TRAPS) {
96 assert(!access_flags.is_native() || byte_code_size == 0,
97 "native methods should not contain byte codes");
98 ConstMethod* cm = ConstMethod::allocate(loader_data,
99 byte_code_size,
100 sizes,
101 method_type,
102 CHECK_NULL);
103 int size = Method::size(access_flags.is_native());
104 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, name);
105 }
106
107 Method::Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name) {
108 NoSafepointVerifier no_safepoint;
109 set_constMethod(xconst);
110 set_access_flags(access_flags);
111 set_intrinsic_id(vmIntrinsics::_none);
112 clear_method_data();
113 clear_method_counters();
114 set_vtable_index(Method::garbage_vtable_index);
115
116 // Fix and bury in Method*
117 set_interpreter_entry(nullptr); // sets i2i entry and from_int
118 set_adapter_entry(nullptr);
119 Method::clear_code(); // from_c/from_i get set to c2i/i2i
120
121 if (access_flags.is_native()) {
122 clear_native_function();
123 set_signature_handler(nullptr);
124 }
125
126 NOT_PRODUCT(set_compiled_invocation_count(0);)
127 // Name is very useful for debugging.
128 NOT_PRODUCT(_name = name;)
129 }
130
131 // Release Method*. The nmethod will be gone when we get here because
132 // we've walked the code cache.
133 void Method::deallocate_contents(ClassLoaderData* loader_data) {
134 MetadataFactory::free_metadata(loader_data, constMethod());
135 set_constMethod(nullptr);
136 MetadataFactory::free_metadata(loader_data, method_data());
137 clear_method_data();
138 MetadataFactory::free_metadata(loader_data, method_counters());
139 clear_method_counters();
140 set_adapter_entry(nullptr);
141 // The nmethod will be gone when we get here.
142 if (code() != nullptr) _code = nullptr;
143 }
144
145 void Method::release_C_heap_structures() {
146 if (method_data()) {
147 method_data()->release_C_heap_structures();
148
149 // Destroy MethodData embedded lock
150 method_data()->~MethodData();
151 }
152 }
153
154 address Method::get_i2c_entry() {
155 if (is_abstract()) {
156 return SharedRuntime::throw_AbstractMethodError_entry();
157 }
158 assert(adapter() != nullptr, "must have");
159 return adapter()->get_i2c_entry();
160 }
161
162 address Method::get_c2i_entry() {
163 if (is_abstract()) {
164 return SharedRuntime::get_handle_wrong_method_abstract_stub();
165 }
166 assert(adapter() != nullptr, "must have");
167 return adapter()->get_c2i_entry();
168 }
169
170 address Method::get_c2i_unverified_entry() {
171 assert(adapter() != nullptr, "must have");
172 return adapter()->get_c2i_unverified_entry();
173 }
174
175 address Method::get_c2i_no_clinit_check_entry() {
176 assert(VM_Version::supports_fast_class_init_checks(), "");
177 assert(adapter() != nullptr, "must have");
178 return adapter()->get_c2i_no_clinit_check_entry();
179 }
180
181 char* Method::name_and_sig_as_C_string() const {
182 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
183 }
184
185 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
186 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
187 }
188
189 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
190 const char* klass_name = klass->external_name();
191 int klass_name_len = (int)strlen(klass_name);
192 int method_name_len = method_name->utf8_length();
193 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
194 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
195 strcpy(dest, klass_name);
196 dest[klass_name_len] = '.';
197 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
198 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
199 dest[len] = 0;
200 return dest;
201 }
202
203 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
204 Symbol* klass_name = klass->name();
205 klass_name->as_klass_external_name(buf, size);
206 int len = (int)strlen(buf);
207
208 if (len < size - 1) {
209 buf[len++] = '.';
210
211 method_name->as_C_string(&(buf[len]), size - len);
212 len = (int)strlen(buf);
213
214 signature->as_C_string(&(buf[len]), size - len);
215 }
216
217 return buf;
218 }
219
220 const char* Method::external_name() const {
221 return external_name(constants()->pool_holder(), name(), signature());
222 }
223
224 void Method::print_external_name(outputStream *os) const {
225 print_external_name(os, constants()->pool_holder(), name(), signature());
226 }
227
228 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
229 stringStream ss;
230 print_external_name(&ss, klass, method_name, signature);
231 return ss.as_string();
232 }
233
234 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
235 signature->print_as_signature_external_return_type(os);
236 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
237 signature->print_as_signature_external_parameters(os);
238 os->print(")");
239 }
240
241 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
242 if (log_is_enabled(Debug, exceptions)) {
243 ResourceMark rm(THREAD);
244 log_debug(exceptions)("Looking for catch handler for exception of type \"%s\" in method \"%s\"",
245 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string());
246 }
247 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
248 // access exception table
249 ExceptionTable table(mh());
250 int length = table.length();
251 // iterate through all entries sequentially
252 constantPoolHandle pool(THREAD, mh->constants());
253 for (int i = 0; i < length; i ++) {
254 //reacquire the table in case a GC happened
255 ExceptionTable table(mh());
256 int beg_bci = table.start_pc(i);
257 int end_bci = table.end_pc(i);
258 assert(beg_bci <= end_bci, "inconsistent exception table");
259 log_debug(exceptions)(" - checking exception table entry for BCI %d to %d",
260 beg_bci, end_bci);
261
262 if (beg_bci <= throw_bci && throw_bci < end_bci) {
263 // exception handler bci range covers throw_bci => investigate further
264 log_debug(exceptions)(" - entry covers throw point BCI %d", throw_bci);
265
266 int handler_bci = table.handler_pc(i);
267 int klass_index = table.catch_type_index(i);
268 if (klass_index == 0) {
269 if (log_is_enabled(Info, exceptions)) {
270 ResourceMark rm(THREAD);
271 log_info(exceptions)("Found catch-all handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
272 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
273 }
274 return handler_bci;
275 } else if (ex_klass == nullptr) {
276 // Is this even possible?
277 if (log_is_enabled(Info, exceptions)) {
278 ResourceMark rm(THREAD);
279 log_info(exceptions)("null exception class is implicitly caught by handler in method \"%s\" at BCI: %d",
280 mh()->name()->as_C_string(), handler_bci);
281 }
282 return handler_bci;
283 } else {
284 if (log_is_enabled(Debug, exceptions)) {
285 ResourceMark rm(THREAD);
286 log_debug(exceptions)(" - resolving catch type \"%s\"",
287 pool->klass_name_at(klass_index)->as_C_string());
288 }
289 // we know the exception class => get the constraint class
290 // this may require loading of the constraint class; if verification
291 // fails or some other exception occurs, return handler_bci
292 Klass* k = pool->klass_at(klass_index, THREAD);
293 if (HAS_PENDING_EXCEPTION) {
294 if (log_is_enabled(Debug, exceptions)) {
295 ResourceMark rm(THREAD);
296 log_debug(exceptions)(" - exception \"%s\" occurred resolving catch type",
297 PENDING_EXCEPTION->klass()->external_name());
298 }
299 return handler_bci;
300 }
301 assert(k != nullptr, "klass not loaded");
302 if (ex_klass->is_subtype_of(k)) {
303 if (log_is_enabled(Info, exceptions)) {
304 ResourceMark rm(THREAD);
305 log_info(exceptions)("Found matching handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
306 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
307 }
308 return handler_bci;
309 }
310 }
311 }
312 }
313
314 if (log_is_enabled(Debug, exceptions)) {
315 ResourceMark rm(THREAD);
316 log_debug(exceptions)("No catch handler found for exception of type \"%s\" in method \"%s\"",
317 ex_klass->external_name(), mh->name()->as_C_string());
318 }
319
320 return -1;
321 }
322
323 void Method::mask_for(int bci, InterpreterOopMap* mask) {
324 methodHandle h_this(Thread::current(), this);
325 mask_for(h_this, bci, mask);
326 }
327
328 void Method::mask_for(const methodHandle& this_mh, int bci, InterpreterOopMap* mask) {
329 assert(this_mh() == this, "Sanity");
330 method_holder()->mask_for(this_mh, bci, mask);
331 }
332
333 int Method::bci_from(address bcp) const {
334 if (is_native() && bcp == nullptr) {
335 return 0;
336 }
337 // Do not have a ResourceMark here because AsyncGetCallTrace stack walking code
338 // may call this after interrupting a nested ResourceMark.
339 assert((is_native() && bcp == code_base()) || contains(bcp) || VMError::is_error_reported(),
340 "bcp doesn't belong to this method. bcp: " PTR_FORMAT, p2i(bcp));
341
342 return int(bcp - code_base());
343 }
344
345
346 int Method::validate_bci(int bci) const {
347 // Called from the verifier, and should return -1 if not valid.
348 return ((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size())) ? bci : -1;
349 }
350
351 // Return bci if it appears to be a valid bcp
352 // Return -1 otherwise.
353 // Used by profiling code, when invalid data is a possibility.
354 // The caller is responsible for validating the Method* itself.
355 int Method::validate_bci_from_bcp(address bcp) const {
356 // keep bci as -1 if not a valid bci
357 int bci = -1;
358 if (bcp == nullptr || bcp == code_base()) {
359 // code_size() may return 0 and we allow 0 here
360 // the method may be native
361 bci = 0;
362 } else if (contains(bcp)) {
363 bci = int(bcp - code_base());
364 }
365 // Assert that if we have dodged any asserts, bci is negative.
366 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
367 return bci;
368 }
369
370 address Method::bcp_from(int bci) const {
371 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
372 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
373 address bcp = code_base() + bci;
374 assert((is_native() && bcp == code_base()) || contains(bcp), "bcp doesn't belong to this method");
375 return bcp;
376 }
377
378 address Method::bcp_from(address bcp) const {
379 if (is_native() && bcp == nullptr) {
380 return code_base();
381 } else {
382 return bcp;
383 }
384 }
385
386 int Method::size(bool is_native) {
387 // If native, then include pointers for native_function and signature_handler
388 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
389 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
390 return align_metadata_size(header_size() + extra_words);
391 }
392
393 Symbol* Method::klass_name() const {
394 return method_holder()->name();
395 }
396
397 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
398 log_trace(aot)("Iter(Method): %p", this);
399
400 if (!method_holder()->is_rewritten()) {
401 it->push(&_constMethod, MetaspaceClosure::_writable);
402 } else {
403 it->push(&_constMethod);
404 }
405 it->push(&_adapter);
406 it->push(&_method_data);
407 it->push(&_method_counters);
408 NOT_PRODUCT(it->push(&_name);)
409 }
410
411 #if INCLUDE_CDS
412 // Attempt to return method to original state. Clear any pointers
413 // (to objects outside the shared spaces). We won't be able to predict
414 // where they should point in a new JVM. Further initialize some
415 // entries now in order allow them to be write protected later.
416
417 void Method::remove_unshareable_info() {
418 unlink_method();
419 if (method_data() != nullptr) {
420 method_data()->remove_unshareable_info();
421 }
422 if (method_counters() != nullptr) {
423 method_counters()->remove_unshareable_info();
424 }
425 if (CDSConfig::is_dumping_adapters() && _adapter != nullptr) {
426 _adapter->remove_unshareable_info();
427 _adapter = nullptr;
428 }
429 JFR_ONLY(REMOVE_METHOD_ID(this);)
430 }
431
432 void Method::restore_unshareable_info(TRAPS) {
433 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
434 if (method_data() != nullptr) {
435 method_data()->restore_unshareable_info(CHECK);
436 }
437 if (method_counters() != nullptr) {
438 method_counters()->restore_unshareable_info(CHECK);
439 }
440 if (_adapter != nullptr) {
441 assert(_adapter->is_linked(), "must be");
442 _from_compiled_entry = _adapter->get_c2i_entry();
443 }
444 assert(!queued_for_compilation(), "method's queued_for_compilation flag should not be set");
445 }
446 #endif
447
448 void Method::set_vtable_index(int index) {
449 if (in_aot_cache() && !AOTMetaspace::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
450 // At runtime initialize_vtable is rerun as part of link_class_impl()
451 // for a shared class loaded by the non-boot loader to obtain the loader
452 // constraints based on the runtime classloaders' context.
453 return; // don't write into the shared class
454 } else {
455 _vtable_index = index;
456 }
457 }
458
459 void Method::set_itable_index(int index) {
460 if (in_aot_cache() && !AOTMetaspace::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
461 // At runtime initialize_itable is rerun as part of link_class_impl()
462 // for a shared class loaded by the non-boot loader to obtain the loader
463 // constraints based on the runtime classloaders' context. The dumptime
464 // itable index should be the same as the runtime index.
465 assert(_vtable_index == itable_index_max - index,
466 "archived itable index is different from runtime index");
467 return; // don't write into the shared class
468 } else {
469 _vtable_index = itable_index_max - index;
470 }
471 assert(valid_itable_index(), "");
472 }
473
474 // The RegisterNatives call being attempted tried to register with a method that
475 // is not native. Ask JVM TI what prefixes have been specified. Then check
476 // to see if the native method is now wrapped with the prefixes. See the
477 // SetNativeMethodPrefix(es) functions in the JVM TI Spec for details.
478 static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS) {
479 #if INCLUDE_JVMTI
480 ResourceMark rm(THREAD);
481 Method* method;
482 int name_len = name->utf8_length();
483 char* name_str = name->as_utf8();
484 int prefix_count;
485 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
486 for (int i = 0; i < prefix_count; i++) {
487 char* prefix = prefixes[i];
488 int prefix_len = (int)strlen(prefix);
489
490 // try adding this prefix to the method name and see if it matches another method name
491 int trial_len = name_len + prefix_len;
492 char* trial_name_str = NEW_RESOURCE_ARRAY(char, trial_len + 1);
493 strcpy(trial_name_str, prefix);
494 strcat(trial_name_str, name_str);
495 TempNewSymbol trial_name = SymbolTable::probe(trial_name_str, trial_len);
496 if (trial_name == nullptr) {
497 continue; // no such symbol, so this prefix wasn't used, try the next prefix
498 }
499 method = k->lookup_method(trial_name, signature);
500 if (method == nullptr) {
501 continue; // signature doesn't match, try the next prefix
502 }
503 if (method->is_native()) {
504 method->set_is_prefixed_native();
505 return method; // wahoo, we found a prefixed version of the method, return it
506 }
507 // found as non-native, so prefix is good, add it, probably just need more prefixes
508 name_len = trial_len;
509 name_str = trial_name_str;
510 }
511 #endif // INCLUDE_JVMTI
512 return nullptr; // not found
513 }
514
515 bool Method::register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS) {
516 Method* method = k->lookup_method(name, signature);
517 if (method == nullptr) {
518 ResourceMark rm(THREAD);
519 stringStream st;
520 st.print("Method '");
521 print_external_name(&st, k, name, signature);
522 st.print("' name or signature does not match");
523 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
524 }
525 if (!method->is_native()) {
526 // trying to register to a non-native method, see if a JVM TI agent has added prefix(es)
527 method = find_prefixed_native(k, name, signature, THREAD);
528 if (method == nullptr) {
529 ResourceMark rm(THREAD);
530 stringStream st;
531 st.print("Method '");
532 print_external_name(&st, k, name, signature);
533 st.print("' is not declared as native");
534 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
535 }
536 }
537
538 if (entry != nullptr) {
539 method->set_native_function(entry, native_bind_event_is_interesting);
540 } else {
541 method->clear_native_function();
542 }
543 if (log_is_enabled(Debug, jni, resolve)) {
544 ResourceMark rm(THREAD);
545 log_debug(jni, resolve)("[Registering JNI native method %s.%s]",
546 method->method_holder()->external_name(),
547 method->name()->as_C_string());
548 }
549 return true;
550 }
551
552 bool Method::was_executed_more_than(int n) {
553 // Invocation counter is reset when the Method* is compiled.
554 // If the method has compiled code we therefore assume it has
555 // be executed more than n times.
556 if (is_accessor() || is_empty_method() || (code() != nullptr)) {
557 // interpreter doesn't bump invocation counter of trivial methods
558 // compiler does not bump invocation counter of compiled methods
559 return true;
560 }
561 else if ((method_counters() != nullptr &&
562 method_counters()->invocation_counter()->carry()) ||
563 (method_data() != nullptr &&
564 method_data()->invocation_counter()->carry())) {
565 // The carry bit is set when the counter overflows and causes
566 // a compilation to occur. We don't know how many times
567 // the counter has been reset, so we simply assume it has
568 // been executed more than n times.
569 return true;
570 } else {
571 return invocation_count() > n;
572 }
573 }
574
575 void Method::print_invocation_count(outputStream* st) {
576 //---< compose+print method return type, klass, name, and signature >---
577 if (is_static()) { st->print("static "); }
578 if (is_final()) { st->print("final "); }
579 if (is_synchronized()) { st->print("synchronized "); }
580 if (is_native()) { st->print("native "); }
581 st->print("%s::", method_holder()->external_name());
582 name()->print_symbol_on(st);
583 signature()->print_symbol_on(st);
584
585 if (WizardMode) {
586 // dump the size of the byte codes
587 st->print(" {%d}", code_size());
588 }
589 st->cr();
590
591 // Counting based on signed int counters tends to overflow with
592 // longer-running workloads on fast machines. The counters under
593 // consideration here, however, are limited in range by counting
594 // logic. See InvocationCounter:count_limit for example.
595 // No "overflow precautions" need to be implemented here.
596 st->print_cr (" interpreter_invocation_count: " INT32_FORMAT_W(11), interpreter_invocation_count());
597 st->print_cr (" invocation_counter: " INT32_FORMAT_W(11), invocation_count());
598 st->print_cr (" backedge_counter: " INT32_FORMAT_W(11), backedge_count());
599
600 if (method_data() != nullptr) {
601 st->print_cr (" decompile_count: " UINT32_FORMAT_W(11), method_data()->decompile_count());
602 }
603
604 #ifndef PRODUCT
605 if (CountCompiledCalls) {
606 st->print_cr (" compiled_invocation_count: " INT64_FORMAT_W(11), compiled_invocation_count());
607 }
608 #endif
609 }
610
611 MethodTrainingData* Method::training_data_or_null() const {
612 MethodCounters* mcs = method_counters();
613 if (mcs == nullptr) {
614 return nullptr;
615 } else {
616 MethodTrainingData* mtd = mcs->method_training_data();
617 if (mtd == mcs->method_training_data_sentinel()) {
618 return nullptr;
619 }
620 return mtd;
621 }
622 }
623
624 bool Method::init_training_data(MethodTrainingData* td) {
625 MethodCounters* mcs = method_counters();
626 if (mcs == nullptr) {
627 return false;
628 } else {
629 return mcs->init_method_training_data(td);
630 }
631 }
632
633 bool Method::install_training_method_data(const methodHandle& method) {
634 MethodTrainingData* mtd = MethodTrainingData::find(method);
635 if (mtd != nullptr && mtd->final_profile() != nullptr) {
636 AtomicAccess::replace_if_null(&method->_method_data, mtd->final_profile());
637 return true;
638 }
639 return false;
640 }
641
642 // Build a MethodData* object to hold profiling information collected on this
643 // method when requested.
644 void Method::build_profiling_method_data(const methodHandle& method, TRAPS) {
645 if (install_training_method_data(method)) {
646 return;
647 }
648 // Do not profile the method if metaspace has hit an OOM previously
649 // allocating profiling data. Callers clear pending exception so don't
650 // add one here.
651 if (ClassLoaderDataGraph::has_metaspace_oom()) {
652 return;
653 }
654
655 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
656 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
657 if (HAS_PENDING_EXCEPTION) {
658 CompileBroker::log_metaspace_failure();
659 ClassLoaderDataGraph::set_metaspace_oom(true);
660 return; // return the exception (which is cleared)
661 }
662
663 if (!AtomicAccess::replace_if_null(&method->_method_data, method_data)) {
664 MetadataFactory::free_metadata(loader_data, method_data);
665 return;
666 }
667
668 if (PrintMethodData && (Verbose || WizardMode)) {
669 ResourceMark rm(THREAD);
670 tty->print("build_profiling_method_data for ");
671 method->print_name(tty);
672 tty->cr();
673 // At the end of the run, the MDO, full of data, will be dumped.
674 }
675 }
676
677 MethodCounters* Method::build_method_counters(Thread* current, Method* m) {
678 // Do not profile the method if metaspace has hit an OOM previously
679 if (ClassLoaderDataGraph::has_metaspace_oom()) {
680 return nullptr;
681 }
682
683 methodHandle mh(current, m);
684 MethodCounters* counters;
685 if (current->is_Java_thread()) {
686 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
687 // Use the TRAPS version for a JavaThread so it will adjust the GC threshold
688 // if needed.
689 counters = MethodCounters::allocate_with_exception(mh, THREAD);
690 if (HAS_PENDING_EXCEPTION) {
691 CLEAR_PENDING_EXCEPTION;
692 }
693 } else {
694 // Call metaspace allocation that doesn't throw exception if the
695 // current thread isn't a JavaThread, ie. the VMThread.
696 counters = MethodCounters::allocate_no_exception(mh);
697 }
698
699 if (counters == nullptr) {
700 CompileBroker::log_metaspace_failure();
701 ClassLoaderDataGraph::set_metaspace_oom(true);
702 return nullptr;
703 }
704
705 if (!mh->init_method_counters(counters)) {
706 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
707 }
708
709 return mh->method_counters();
710 }
711
712 bool Method::init_method_counters(MethodCounters* counters) {
713 // Try to install a pointer to MethodCounters, return true on success.
714 return AtomicAccess::replace_if_null(&_method_counters, counters);
715 }
716
717 void Method::set_exception_handler_entered(int handler_bci) {
718 if (ProfileExceptionHandlers) {
719 MethodData* mdo = method_data();
720 if (mdo != nullptr) {
721 BitData handler_data = mdo->exception_handler_bci_to_data(handler_bci);
722 handler_data.set_exception_handler_entered();
723 }
724 }
725 }
726
727 int Method::extra_stack_words() {
728 // not an inline function, to avoid a header dependency on Interpreter
729 return extra_stack_entries() * Interpreter::stackElementSize;
730 }
731
732 bool Method::compute_has_loops_flag() {
733 BytecodeStream bcs(methodHandle(Thread::current(), this));
734 Bytecodes::Code bc;
735
736 while ((bc = bcs.next()) >= 0) {
737 switch (bc) {
738 case Bytecodes::_ifeq:
739 case Bytecodes::_ifnull:
740 case Bytecodes::_iflt:
741 case Bytecodes::_ifle:
742 case Bytecodes::_ifne:
743 case Bytecodes::_ifnonnull:
744 case Bytecodes::_ifgt:
745 case Bytecodes::_ifge:
746 case Bytecodes::_if_icmpeq:
747 case Bytecodes::_if_icmpne:
748 case Bytecodes::_if_icmplt:
749 case Bytecodes::_if_icmpgt:
750 case Bytecodes::_if_icmple:
751 case Bytecodes::_if_icmpge:
752 case Bytecodes::_if_acmpeq:
753 case Bytecodes::_if_acmpne:
754 case Bytecodes::_goto:
755 case Bytecodes::_jsr:
756 if (bcs.dest() < bcs.next_bci()) {
757 return set_has_loops();
758 }
759 break;
760
761 case Bytecodes::_goto_w:
762 case Bytecodes::_jsr_w:
763 if (bcs.dest_w() < bcs.next_bci()) {
764 return set_has_loops();
765 }
766 break;
767
768 case Bytecodes::_lookupswitch: {
769 Bytecode_lookupswitch lookupswitch(this, bcs.bcp());
770 if (lookupswitch.default_offset() < 0) {
771 return set_has_loops();
772 } else {
773 for (int i = 0; i < lookupswitch.number_of_pairs(); ++i) {
774 LookupswitchPair pair = lookupswitch.pair_at(i);
775 if (pair.offset() < 0) {
776 return set_has_loops();
777 }
778 }
779 }
780 break;
781 }
782 case Bytecodes::_tableswitch: {
783 Bytecode_tableswitch tableswitch(this, bcs.bcp());
784 if (tableswitch.default_offset() < 0) {
785 return set_has_loops();
786 } else {
787 for (int i = 0; i < tableswitch.length(); ++i) {
788 if (tableswitch.dest_offset_at(i) < 0) {
789 return set_has_loops();
790 }
791 }
792 }
793 break;
794 }
795 default:
796 break;
797 }
798 }
799
800 _flags.set_has_loops_flag_init(true);
801 return false;
802 }
803
804 bool Method::is_final_method(AccessFlags class_access_flags) const {
805 // or "does_not_require_vtable_entry"
806 // default method or overpass can occur, is not final (reuses vtable entry)
807 // private methods in classes get vtable entries for backward class compatibility.
808 if (is_overpass() || is_default_method()) return false;
809 return is_final() || class_access_flags.is_final();
810 }
811
812 bool Method::is_final_method() const {
813 return is_final_method(method_holder()->access_flags());
814 }
815
816 bool Method::is_default_method() const {
817 if (method_holder() != nullptr &&
818 method_holder()->is_interface() &&
819 !is_abstract() && !is_private()) {
820 return true;
821 } else {
822 return false;
823 }
824 }
825
826 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
827 if (is_final_method(class_access_flags)) return true;
828 #ifdef ASSERT
829 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
830 if (class_access_flags.is_interface()) {
831 ResourceMark rm;
832 assert(is_nonv == is_static() || is_nonv == is_private(),
833 "nonvirtual unexpected for non-static, non-private: %s",
834 name_and_sig_as_C_string());
835 }
836 #endif
837 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
838 return vtable_index() == nonvirtual_vtable_index;
839 }
840
841 bool Method::can_be_statically_bound() const {
842 return can_be_statically_bound(method_holder()->access_flags());
843 }
844
845 bool Method::can_be_statically_bound(InstanceKlass* context) const {
846 return (method_holder() == context) && can_be_statically_bound();
847 }
848
849 /**
850 * Returns false if this is one of specially treated methods for
851 * which we have to provide stack trace in throw in compiled code.
852 * Returns true otherwise.
853 */
854 bool Method::can_omit_stack_trace() {
855 if (klass_name() == vmSymbols::sun_invoke_util_ValueConversions()) {
856 return false; // All methods in sun.invoke.util.ValueConversions
857 }
858 return true;
859 }
860
861 bool Method::is_accessor() const {
862 return is_getter() || is_setter();
863 }
864
865 bool Method::is_getter() const {
866 if (code_size() != 5) return false;
867 if (size_of_parameters() != 1) return false;
868 if (java_code_at(0) != Bytecodes::_aload_0) return false;
869 if (java_code_at(1) != Bytecodes::_getfield) return false;
870 switch (java_code_at(4)) {
871 case Bytecodes::_ireturn:
872 case Bytecodes::_lreturn:
873 case Bytecodes::_freturn:
874 case Bytecodes::_dreturn:
875 case Bytecodes::_areturn:
876 break;
877 default:
878 return false;
879 }
880 return true;
881 }
882
883 bool Method::is_setter() const {
884 if (code_size() != 6) return false;
885 if (java_code_at(0) != Bytecodes::_aload_0) return false;
886 switch (java_code_at(1)) {
887 case Bytecodes::_iload_1:
888 case Bytecodes::_aload_1:
889 case Bytecodes::_fload_1:
890 if (size_of_parameters() != 2) return false;
891 break;
892 case Bytecodes::_dload_1:
893 case Bytecodes::_lload_1:
894 if (size_of_parameters() != 3) return false;
895 break;
896 default:
897 return false;
898 }
899 if (java_code_at(2) != Bytecodes::_putfield) return false;
900 if (java_code_at(5) != Bytecodes::_return) return false;
901 return true;
902 }
903
904 bool Method::is_constant_getter() const {
905 int last_index = code_size() - 1;
906 // Check if the first 1-3 bytecodes are a constant push
907 // and the last bytecode is a return.
908 return (2 <= code_size() && code_size() <= 4 &&
909 Bytecodes::is_const(java_code_at(0)) &&
910 Bytecodes::length_for(java_code_at(0)) == last_index &&
911 Bytecodes::is_return(java_code_at(last_index)));
912 }
913
914 bool Method::has_valid_initializer_flags() const {
915 return (is_static() ||
916 method_holder()->major_version() < 51);
917 }
918
919 bool Method::is_static_initializer() const {
920 // For classfiles version 51 or greater, ensure that the clinit method is
921 // static. Non-static methods with the name "<clinit>" are not static
922 // initializers. (older classfiles exempted for backward compatibility)
923 return name() == vmSymbols::class_initializer_name() &&
924 has_valid_initializer_flags();
925 }
926
927 bool Method::is_object_initializer() const {
928 return name() == vmSymbols::object_initializer_name();
929 }
930
931 bool Method::needs_clinit_barrier() const {
932 return is_static() && !method_holder()->is_initialized();
933 }
934
935 bool Method::is_object_wait0() const {
936 return klass_name() == vmSymbols::java_lang_Object()
937 && name() == vmSymbols::wait_name();
938 }
939
940 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
941 int length = method->checked_exceptions_length();
942 if (length == 0) { // common case
943 return objArrayHandle(THREAD, Universe::the_empty_class_array());
944 } else {
945 methodHandle h_this(THREAD, method);
946 objArrayOop m_oop = oopFactory::new_objArray(vmClasses::Class_klass(), length, CHECK_(objArrayHandle()));
947 objArrayHandle mirrors (THREAD, m_oop);
948 for (int i = 0; i < length; i++) {
949 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
950 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
951 if (log_is_enabled(Warning, exceptions) &&
952 !k->is_subclass_of(vmClasses::Throwable_klass())) {
953 ResourceMark rm(THREAD);
954 log_warning(exceptions)(
955 "Class %s in throws clause of method %s is not a subtype of class java.lang.Throwable",
956 k->external_name(), method->external_name());
957 }
958 mirrors->obj_at_put(i, k->java_mirror());
959 }
960 return mirrors;
961 }
962 };
963
964
965 int Method::line_number_from_bci(int bci) const {
966 int best_bci = 0;
967 int best_line = -1;
968 if (bci == SynchronizationEntryBCI) bci = 0;
969 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
970 // The line numbers are a short array of 2-tuples [start_pc, line_number].
971 // Not necessarily sorted and not necessarily one-to-one.
972 CompressedLineNumberReadStream stream(compressed_linenumber_table());
973 while (stream.read_pair()) {
974 if (stream.bci() == bci) {
975 // perfect match
976 return stream.line();
977 } else {
978 // update best_bci/line
979 if (stream.bci() < bci && stream.bci() >= best_bci) {
980 best_bci = stream.bci();
981 best_line = stream.line();
982 }
983 }
984 }
985 }
986 return best_line;
987 }
988
989
990 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
991 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
992 Thread *thread = Thread::current();
993 Symbol* klass_name = constants()->klass_name_at(klass_index);
994 Handle loader(thread, method_holder()->class_loader());
995 return SystemDictionary::find_instance_klass(thread, klass_name, loader) != nullptr;
996 } else {
997 return true;
998 }
999 }
1000
1001
1002 bool Method::is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved) const {
1003 int klass_index = constants()->klass_ref_index_at(refinfo_index, bc);
1004 if (must_be_resolved) {
1005 // Make sure klass is resolved in constantpool.
1006 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
1007 }
1008 return is_klass_loaded_by_klass_index(klass_index);
1009 }
1010
1011
1012 void Method::set_native_function(address function, bool post_event_flag) {
1013 assert(function != nullptr, "use clear_native_function to unregister natives");
1014 assert(!is_special_native_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
1015 address* native_function = native_function_addr();
1016
1017 // We can see racers trying to place the same native function into place. Once
1018 // is plenty.
1019 address current = *native_function;
1020 if (current == function) return;
1021 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
1022 function != nullptr) {
1023 // native_method_throw_unsatisfied_link_error_entry() should only
1024 // be passed when post_event_flag is false.
1025 assert(function !=
1026 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1027 "post_event_flag mismatch");
1028
1029 // post the bind event, and possible change the bind function
1030 JvmtiExport::post_native_method_bind(this, &function);
1031 }
1032 *native_function = function;
1033 // This function can be called more than once. We must make sure that we always
1034 // use the latest registered method -> check if a stub already has been generated.
1035 // If so, we have to make it not_entrant.
1036 nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
1037 if (nm != nullptr) {
1038 nm->make_not_entrant(nmethod::InvalidationReason::SET_NATIVE_FUNCTION);
1039 }
1040 }
1041
1042
1043 bool Method::has_native_function() const {
1044 if (is_special_native_intrinsic())
1045 return false; // special-cased in SharedRuntime::generate_native_wrapper
1046 address func = native_function();
1047 return (func != nullptr && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
1048 }
1049
1050
1051 void Method::clear_native_function() {
1052 // Note: is_method_handle_intrinsic() is allowed here.
1053 set_native_function(
1054 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1055 !native_bind_event_is_interesting);
1056 this->unlink_code();
1057 }
1058
1059
1060 void Method::set_signature_handler(address handler) {
1061 address* signature_handler = signature_handler_addr();
1062 *signature_handler = handler;
1063 }
1064
1065
1066 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
1067 assert(reason != nullptr, "must provide a reason");
1068 if (PrintCompilation && report) {
1069 ttyLocker ttyl;
1070 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
1071 if (comp_level == CompLevel_all) {
1072 tty->print("all levels ");
1073 } else {
1074 tty->print("level %d ", comp_level);
1075 }
1076 this->print_short_name(tty);
1077 int size = this->code_size();
1078 if (size > 0) {
1079 tty->print(" (%d bytes)", size);
1080 }
1081 if (reason != nullptr) {
1082 tty->print(" %s", reason);
1083 }
1084 tty->cr();
1085 }
1086 if ((TraceDeoptimization || LogCompilation) && (xtty != nullptr)) {
1087 ttyLocker ttyl;
1088 xtty->begin_elem("make_not_compilable thread='%zu' osr='%d' level='%d'",
1089 os::current_thread_id(), is_osr, comp_level);
1090 if (reason != nullptr) {
1091 xtty->print(" reason=\'%s\'", reason);
1092 }
1093 xtty->method(this);
1094 xtty->stamp();
1095 xtty->end_elem();
1096 }
1097 }
1098
1099 bool Method::is_always_compilable() const {
1100 // Generated adapters must be compiled
1101 if (is_special_native_intrinsic() && is_synthetic()) {
1102 assert(!is_not_c1_compilable(), "sanity check");
1103 assert(!is_not_c2_compilable(), "sanity check");
1104 return true;
1105 }
1106
1107 return false;
1108 }
1109
1110 bool Method::is_not_compilable(int comp_level) const {
1111 if (number_of_breakpoints() > 0)
1112 return true;
1113 if (is_always_compilable())
1114 return false;
1115 if (comp_level == CompLevel_any)
1116 return is_not_c1_compilable() && is_not_c2_compilable();
1117 if (is_c1_compile(comp_level))
1118 return is_not_c1_compilable();
1119 if (is_c2_compile(comp_level))
1120 return is_not_c2_compilable();
1121 return false;
1122 }
1123
1124 // call this when compiler finds that this method is not compilable
1125 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
1126 if (is_always_compilable()) {
1127 // Don't mark a method which should be always compilable
1128 return;
1129 }
1130 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
1131 if (comp_level == CompLevel_all) {
1132 set_is_not_c1_compilable();
1133 set_is_not_c2_compilable();
1134 } else {
1135 if (is_c1_compile(comp_level))
1136 set_is_not_c1_compilable();
1137 if (is_c2_compile(comp_level))
1138 set_is_not_c2_compilable();
1139 }
1140 assert(!CompilationPolicy::can_be_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1141 }
1142
1143 bool Method::is_not_osr_compilable(int comp_level) const {
1144 if (is_not_compilable(comp_level))
1145 return true;
1146 if (comp_level == CompLevel_any)
1147 return is_not_c1_osr_compilable() && is_not_c2_osr_compilable();
1148 if (is_c1_compile(comp_level))
1149 return is_not_c1_osr_compilable();
1150 if (is_c2_compile(comp_level))
1151 return is_not_c2_osr_compilable();
1152 return false;
1153 }
1154
1155 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
1156 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
1157 if (comp_level == CompLevel_all) {
1158 set_is_not_c1_osr_compilable();
1159 set_is_not_c2_osr_compilable();
1160 } else {
1161 if (is_c1_compile(comp_level))
1162 set_is_not_c1_osr_compilable();
1163 if (is_c2_compile(comp_level))
1164 set_is_not_c2_osr_compilable();
1165 }
1166 assert(!CompilationPolicy::can_be_osr_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1167 }
1168
1169 // Revert to using the interpreter and clear out the nmethod
1170 void Method::clear_code() {
1171 // this may be null if c2i adapters have not been made yet
1172 // Only should happen at allocate time.
1173 if (adapter() == nullptr) {
1174 _from_compiled_entry = nullptr;
1175 } else {
1176 _from_compiled_entry = adapter()->get_c2i_entry();
1177 }
1178 OrderAccess::storestore();
1179 _from_interpreted_entry = _i2i_entry;
1180 OrderAccess::storestore();
1181 _code = nullptr;
1182 }
1183
1184 void Method::unlink_code(nmethod *compare) {
1185 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1186 // We need to check if either the _code or _from_compiled_code_entry_point
1187 // refer to this nmethod because there is a race in setting these two fields
1188 // in Method* as seen in bugid 4947125.
1189 if (code() == compare ||
1190 from_compiled_entry() == compare->verified_entry_point()) {
1191 clear_code();
1192 }
1193 }
1194
1195 void Method::unlink_code() {
1196 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1197 clear_code();
1198 }
1199
1200 #if INCLUDE_CDS
1201 // Called by class data sharing to remove any entry points (which are not shared)
1202 void Method::unlink_method() {
1203 assert(CDSConfig::is_dumping_archive(), "sanity");
1204 _code = nullptr;
1205 if (!CDSConfig::is_dumping_adapters()) {
1206 _adapter = nullptr;
1207 }
1208 _i2i_entry = nullptr;
1209 _from_compiled_entry = nullptr;
1210 _from_interpreted_entry = nullptr;
1211
1212 if (is_native()) {
1213 *native_function_addr() = nullptr;
1214 set_signature_handler(nullptr);
1215 }
1216 NOT_PRODUCT(set_compiled_invocation_count(0);)
1217
1218 clear_method_data();
1219 clear_method_counters();
1220 clear_is_not_c1_compilable();
1221 clear_is_not_c1_osr_compilable();
1222 clear_is_not_c2_compilable();
1223 clear_is_not_c2_osr_compilable();
1224 clear_queued_for_compilation();
1225
1226 remove_unshareable_flags();
1227 }
1228
1229 void Method::remove_unshareable_flags() {
1230 // clear all the flags that shouldn't be in the archived version
1231 assert(!is_old(), "must be");
1232 assert(!is_obsolete(), "must be");
1233 assert(!is_deleted(), "must be");
1234
1235 set_is_prefixed_native(false);
1236 set_queued_for_compilation(false);
1237 set_is_not_c2_compilable(false);
1238 set_is_not_c1_compilable(false);
1239 set_is_not_c2_osr_compilable(false);
1240 set_on_stack_flag(false);
1241 }
1242 #endif
1243
1244 // Called when the method_holder is getting linked. Setup entrypoints so the method
1245 // is ready to be called from interpreter, compiler, and vtables.
1246 void Method::link_method(const methodHandle& h_method, TRAPS) {
1247 if (log_is_enabled(Info, perf, class, link)) {
1248 ClassLoader::perf_ik_link_methods_count()->inc();
1249 }
1250
1251 // If the code cache is full, we may reenter this function for the
1252 // leftover methods that weren't linked.
1253 if (adapter() != nullptr) {
1254 if (adapter()->in_aot_cache()) {
1255 assert(adapter()->is_linked(), "Adapter is shared but not linked");
1256 } else {
1257 return;
1258 }
1259 }
1260 assert( _code == nullptr, "nothing compiled yet" );
1261
1262 // Setup interpreter entrypoint
1263 assert(this == h_method(), "wrong h_method()" );
1264
1265 assert(adapter() == nullptr || adapter()->is_linked(), "init'd to null or restored from cache");
1266 address entry = Interpreter::entry_for_method(h_method);
1267 assert(entry != nullptr, "interpreter entry must be non-null");
1268 // Sets both _i2i_entry and _from_interpreted_entry
1269 set_interpreter_entry(entry);
1270
1271 // Don't overwrite already registered native entries.
1272 if (is_native() && !has_native_function()) {
1273 set_native_function(
1274 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1275 !native_bind_event_is_interesting);
1276 }
1277
1278 // Setup compiler entrypoint. This is made eagerly, so we do not need
1279 // special handling of vtables. An alternative is to make adapters more
1280 // lazily by calling make_adapter() from from_compiled_entry() for the
1281 // normal calls. For vtable calls life gets more complicated. When a
1282 // call-site goes mega-morphic we need adapters in all methods which can be
1283 // called from the vtable. We need adapters on such methods that get loaded
1284 // later. Ditto for mega-morphic itable calls. If this proves to be a
1285 // problem we'll make these lazily later.
1286 if (is_abstract()) {
1287 h_method->_from_compiled_entry = SharedRuntime::get_handle_wrong_method_abstract_stub();
1288 } else if (_adapter == nullptr) {
1289 (void) make_adapters(h_method, CHECK);
1290 #ifndef ZERO
1291 assert(adapter()->is_linked(), "Adapter must have been linked");
1292 #endif
1293 h_method->_from_compiled_entry = adapter()->get_c2i_entry();
1294 }
1295
1296 // ONLY USE the h_method now as make_adapter may have blocked
1297
1298 if (h_method->is_continuation_native_intrinsic()) {
1299 _from_interpreted_entry = nullptr;
1300 _from_compiled_entry = nullptr;
1301 _i2i_entry = nullptr;
1302 if (Continuations::enabled()) {
1303 assert(!Threads::is_vm_complete(), "should only be called during vm init");
1304 AdapterHandlerLibrary::create_native_wrapper(h_method);
1305 if (!h_method->has_compiled_code()) {
1306 THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), "Initial size of CodeCache is too small");
1307 }
1308 assert(_from_interpreted_entry == get_i2c_entry(), "invariant");
1309 }
1310 }
1311 }
1312
1313 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1314 assert(!mh->is_abstract(), "abstract methods do not have adapters");
1315 PerfTraceTime timer(ClassLoader::perf_method_adapters_time());
1316
1317 // Adapters for compiled code are made eagerly here. They are fairly
1318 // small (generally < 100 bytes) and quick to make (and cached and shared)
1319 // so making them eagerly shouldn't be too expensive.
1320 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1321 if (adapter == nullptr ) {
1322 if (!is_init_completed()) {
1323 // Don't throw exceptions during VM initialization because java.lang.* classes
1324 // might not have been initialized, causing problems when constructing the
1325 // Java exception object.
1326 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1327 } else {
1328 THROW_MSG_NULL(vmSymbols::java_lang_OutOfMemoryError(), "Out of space in CodeCache for adapters");
1329 }
1330 }
1331
1332 mh->set_adapter_entry(adapter);
1333 return adapter->get_c2i_entry();
1334 }
1335
1336 // The verified_code_entry() must be called when a invoke is resolved
1337 // on this method.
1338
1339 // It returns the compiled code entry point, after asserting not null.
1340 // This function is called after potential safepoints so that nmethod
1341 // or adapter that it points to is still live and valid.
1342 // This function must not hit a safepoint!
1343 address Method::verified_code_entry() {
1344 DEBUG_ONLY(NoSafepointVerifier nsv;)
1345 assert(_from_compiled_entry != nullptr, "must be set");
1346 return _from_compiled_entry;
1347 }
1348
1349 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1350 // (could be racing a deopt).
1351 // Not inline to avoid circular ref.
1352 bool Method::check_code() const {
1353 // cached in a register or local. There's a race on the value of the field.
1354 nmethod *code = AtomicAccess::load_acquire(&_code);
1355 return code == nullptr || (code->method() == nullptr) || (code->method() == (Method*)this && !code->is_osr_method());
1356 }
1357
1358 // Install compiled code. Instantly it can execute.
1359 void Method::set_code(const methodHandle& mh, nmethod *code) {
1360 assert_lock_strong(NMethodState_lock);
1361 assert( code, "use clear_code to remove code" );
1362 assert( mh->check_code(), "" );
1363
1364 guarantee(mh->adapter() != nullptr, "Adapter blob must already exist!");
1365
1366 // These writes must happen in this order, because the interpreter will
1367 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1368 // which jumps to _from_compiled_entry.
1369 mh->_code = code; // Assign before allowing compiled code to exec
1370
1371 int comp_level = code->comp_level();
1372 // In theory there could be a race here. In practice it is unlikely
1373 // and not worth worrying about.
1374 if (comp_level > mh->highest_comp_level()) {
1375 mh->set_highest_comp_level(comp_level);
1376 }
1377
1378 OrderAccess::storestore();
1379 mh->_from_compiled_entry = code->verified_entry_point();
1380 OrderAccess::storestore();
1381
1382 if (mh->is_continuation_native_intrinsic()) {
1383 assert(mh->_from_interpreted_entry == nullptr, "initialized incorrectly"); // see link_method
1384
1385 if (mh->is_continuation_enter_intrinsic()) {
1386 // This is the entry used when we're in interpreter-only mode; see InterpreterMacroAssembler::jump_from_interpreted
1387 mh->_i2i_entry = ContinuationEntry::interpreted_entry();
1388 } else if (mh->is_continuation_yield_intrinsic()) {
1389 mh->_i2i_entry = mh->get_i2c_entry();
1390 } else {
1391 guarantee(false, "Unknown Continuation native intrinsic");
1392 }
1393 // This must come last, as it is what's tested in LinkResolver::resolve_static_call
1394 AtomicAccess::release_store(&mh->_from_interpreted_entry , mh->get_i2c_entry());
1395 } else if (!mh->is_method_handle_intrinsic()) {
1396 // Instantly compiled code can execute.
1397 mh->_from_interpreted_entry = mh->get_i2c_entry();
1398 }
1399 }
1400
1401
1402 bool Method::is_overridden_in(Klass* k) const {
1403 InstanceKlass* ik = InstanceKlass::cast(k);
1404
1405 if (ik->is_interface()) return false;
1406
1407 // If method is an interface, we skip it - except if it
1408 // is a miranda method
1409 if (method_holder()->is_interface()) {
1410 // Check that method is not a miranda method
1411 if (ik->lookup_method(name(), signature()) == nullptr) {
1412 // No implementation exist - so miranda method
1413 return false;
1414 }
1415 return true;
1416 }
1417
1418 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1419 if (!has_vtable_index()) {
1420 return false;
1421 } else {
1422 Method* vt_m = ik->method_at_vtable(vtable_index());
1423 return vt_m != this;
1424 }
1425 }
1426
1427
1428 // give advice about whether this Method* should be cached or not
1429 bool Method::should_not_be_cached() const {
1430 if (is_old()) {
1431 // This method has been redefined. It is either EMCP or obsolete
1432 // and we don't want to cache it because that would pin the method
1433 // down and prevent it from being collectible if and when it
1434 // finishes executing.
1435 return true;
1436 }
1437
1438 // caching this method should be just fine
1439 return false;
1440 }
1441
1442
1443 /**
1444 * Returns true if this is one of the specially treated methods for
1445 * security related stack walks (like Reflection.getCallerClass).
1446 */
1447 bool Method::is_ignored_by_security_stack_walk() const {
1448 if (intrinsic_id() == vmIntrinsics::_invoke) {
1449 // This is Method.invoke() -- ignore it
1450 return true;
1451 }
1452 if (method_holder()->is_subclass_of(vmClasses::reflect_MethodAccessorImpl_klass())) {
1453 // This is an auxiliary frame -- ignore it
1454 return true;
1455 }
1456 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1457 // This is an internal adapter frame for method handles -- ignore it
1458 return true;
1459 }
1460 return false;
1461 }
1462
1463
1464 // Constant pool structure for invoke methods:
1465 enum {
1466 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1467 _imcp_invoke_signature, // utf8: (variable Symbol*)
1468 _imcp_limit
1469 };
1470
1471 // Test if this method is an MH adapter frame generated by Java code.
1472 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1473 bool Method::is_compiled_lambda_form() const {
1474 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1475 }
1476
1477 // Test if this method is an internal MH primitive method.
1478 bool Method::is_method_handle_intrinsic() const {
1479 vmIntrinsics::ID iid = intrinsic_id();
1480 return (MethodHandles::is_signature_polymorphic(iid) &&
1481 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1482 }
1483
1484 bool Method::has_member_arg() const {
1485 vmIntrinsics::ID iid = intrinsic_id();
1486 return (MethodHandles::is_signature_polymorphic(iid) &&
1487 MethodHandles::has_member_arg(iid));
1488 }
1489
1490 // Make an instance of a signature-polymorphic internal MH primitive.
1491 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1492 Symbol* signature,
1493 TRAPS) {
1494 ResourceMark rm(THREAD);
1495 methodHandle empty;
1496
1497 InstanceKlass* holder = vmClasses::MethodHandle_klass();
1498 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1499 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1500
1501 log_info(methodhandles)("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1502
1503 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1504 name->increment_refcount();
1505 signature->increment_refcount();
1506
1507 int cp_length = _imcp_limit;
1508 ClassLoaderData* loader_data = holder->class_loader_data();
1509 constantPoolHandle cp;
1510 {
1511 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1512 cp = constantPoolHandle(THREAD, cp_oop);
1513 }
1514 cp->copy_fields(holder->constants());
1515 cp->set_pool_holder(holder);
1516 cp->symbol_at_put(_imcp_invoke_name, name);
1517 cp->symbol_at_put(_imcp_invoke_signature, signature);
1518 cp->set_has_preresolution();
1519 cp->set_is_for_method_handle_intrinsic();
1520
1521 // decide on access bits: public or not?
1522 u2 flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1523 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1524 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1525 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1526
1527 methodHandle m;
1528 {
1529 InlineTableSizes sizes;
1530 Method* m_oop = Method::allocate(loader_data, 0,
1531 accessFlags_from(flags_bits), &sizes,
1532 ConstMethod::NORMAL,
1533 name,
1534 CHECK_(empty));
1535 m = methodHandle(THREAD, m_oop);
1536 }
1537 m->set_constants(cp());
1538 m->set_name_index(_imcp_invoke_name);
1539 m->set_signature_index(_imcp_invoke_signature);
1540 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1541 assert(m->signature() == signature, "");
1542 m->constMethod()->compute_from_signature(signature, must_be_static);
1543 m->init_intrinsic_id(klass_id_for_intrinsics(m->method_holder()));
1544 assert(m->is_method_handle_intrinsic(), "");
1545 #ifdef ASSERT
1546 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1547 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1548 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1549 #endif //ASSERT
1550
1551 // Finally, set up its entry points.
1552 assert(m->can_be_statically_bound(), "");
1553 m->set_vtable_index(Method::nonvirtual_vtable_index);
1554 m->link_method(m, CHECK_(empty));
1555
1556 if (iid == vmIntrinsics::_linkToNative) {
1557 m->set_interpreter_entry(m->adapter()->get_i2c_entry());
1558 }
1559 if (log_is_enabled(Debug, methodhandles)) {
1560 LogTarget(Debug, methodhandles) lt;
1561 LogStream ls(lt);
1562 m->print_on(&ls);
1563 }
1564
1565 return m;
1566 }
1567
1568 #if INCLUDE_CDS
1569 void Method::restore_archived_method_handle_intrinsic(methodHandle m, TRAPS) {
1570 if (m->adapter() != nullptr) {
1571 m->set_from_compiled_entry(m->adapter()->get_c2i_entry());
1572 }
1573 m->link_method(m, CHECK);
1574
1575 if (m->intrinsic_id() == vmIntrinsics::_linkToNative) {
1576 m->set_interpreter_entry(m->adapter()->get_i2c_entry());
1577 }
1578 }
1579 #endif
1580
1581 Klass* Method::check_non_bcp_klass(Klass* klass) {
1582 if (klass != nullptr && klass->class_loader() != nullptr) {
1583 if (klass->is_objArray_klass())
1584 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1585 return klass;
1586 }
1587 return nullptr;
1588 }
1589
1590
1591 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1592 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1593 // Code below does not work for native methods - they should never get rewritten anyway
1594 assert(!m->is_native(), "cannot rewrite native methods");
1595 // Allocate new Method*
1596 AccessFlags flags = m->access_flags();
1597
1598 ConstMethod* cm = m->constMethod();
1599 int checked_exceptions_len = cm->checked_exceptions_length();
1600 int localvariable_len = cm->localvariable_table_length();
1601 int exception_table_len = cm->exception_table_length();
1602 int method_parameters_len = cm->method_parameters_length();
1603 int method_annotations_len = cm->method_annotations_length();
1604 int parameter_annotations_len = cm->parameter_annotations_length();
1605 int type_annotations_len = cm->type_annotations_length();
1606 int default_annotations_len = cm->default_annotations_length();
1607
1608 InlineTableSizes sizes(
1609 localvariable_len,
1610 new_compressed_linenumber_size,
1611 exception_table_len,
1612 checked_exceptions_len,
1613 method_parameters_len,
1614 cm->generic_signature_index(),
1615 method_annotations_len,
1616 parameter_annotations_len,
1617 type_annotations_len,
1618 default_annotations_len,
1619 0);
1620
1621 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1622 Method* newm_oop = Method::allocate(loader_data,
1623 new_code_length,
1624 flags,
1625 &sizes,
1626 m->method_type(),
1627 m->name(),
1628 CHECK_(methodHandle()));
1629 methodHandle newm (THREAD, newm_oop);
1630
1631 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1632 ConstMethod* newcm = newm->constMethod();
1633 int new_const_method_size = newm->constMethod()->size();
1634
1635 // This works because the source and target are both Methods. Some compilers
1636 // (e.g., clang) complain that the target vtable pointer will be stomped,
1637 // so cast away newm()'s and m()'s Methodness.
1638 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1639
1640 // Create shallow copy of ConstMethod.
1641 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1642
1643 // Reset correct method/const method, method size, and parameter info
1644 newm->set_constMethod(newcm);
1645 newm->constMethod()->set_code_size(new_code_length);
1646 newm->constMethod()->set_constMethod_size(new_const_method_size);
1647 assert(newm->code_size() == new_code_length, "check");
1648 assert(newm->method_parameters_length() == method_parameters_len, "check");
1649 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1650 assert(newm->exception_table_length() == exception_table_len, "check");
1651 assert(newm->localvariable_table_length() == localvariable_len, "check");
1652 // Copy new byte codes
1653 memcpy(newm->code_base(), new_code, new_code_length);
1654 // Copy line number table
1655 if (new_compressed_linenumber_size > 0) {
1656 memcpy(newm->compressed_linenumber_table(),
1657 new_compressed_linenumber_table,
1658 new_compressed_linenumber_size);
1659 }
1660 // Copy method_parameters
1661 if (method_parameters_len > 0) {
1662 memcpy(newm->method_parameters_start(),
1663 m->method_parameters_start(),
1664 method_parameters_len * sizeof(MethodParametersElement));
1665 }
1666 // Copy checked_exceptions
1667 if (checked_exceptions_len > 0) {
1668 memcpy(newm->checked_exceptions_start(),
1669 m->checked_exceptions_start(),
1670 checked_exceptions_len * sizeof(CheckedExceptionElement));
1671 }
1672 // Copy exception table
1673 if (exception_table_len > 0) {
1674 memcpy(newm->exception_table_start(),
1675 m->exception_table_start(),
1676 exception_table_len * sizeof(ExceptionTableElement));
1677 }
1678 // Copy local variable number table
1679 if (localvariable_len > 0) {
1680 memcpy(newm->localvariable_table_start(),
1681 m->localvariable_table_start(),
1682 localvariable_len * sizeof(LocalVariableTableElement));
1683 }
1684 // Copy stackmap table
1685 if (m->has_stackmap_table()) {
1686 int code_attribute_length = m->stackmap_data()->length();
1687 Array<u1>* stackmap_data =
1688 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_(methodHandle()));
1689 memcpy((void*)stackmap_data->adr_at(0),
1690 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1691 newm->set_stackmap_data(stackmap_data);
1692 }
1693
1694 // copy annotations over to new method
1695 newcm->copy_annotations_from(loader_data, cm, CHECK_(methodHandle()));
1696 return newm;
1697 }
1698
1699 vmSymbolID Method::klass_id_for_intrinsics(const Klass* holder) {
1700 // if loader is not the default loader (i.e., non-null), we can't know the intrinsics
1701 // because we are not loading from core libraries
1702 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1703 // which does not use the class default class loader so we check for its loader here
1704 const InstanceKlass* ik = InstanceKlass::cast(holder);
1705 if ((ik->class_loader() != nullptr) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1706 return vmSymbolID::NO_SID; // regardless of name, no intrinsics here
1707 }
1708
1709 // see if the klass name is well-known:
1710 Symbol* klass_name = ik->name();
1711 vmSymbolID id = vmSymbols::find_sid(klass_name);
1712 if (id != vmSymbolID::NO_SID && vmIntrinsics::class_has_intrinsics(id)) {
1713 return id;
1714 } else {
1715 return vmSymbolID::NO_SID;
1716 }
1717 }
1718
1719 void Method::init_intrinsic_id(vmSymbolID klass_id) {
1720 assert(_intrinsic_id == static_cast<int>(vmIntrinsics::_none), "do this just once");
1721 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1722 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1723 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1724
1725 // the klass name is well-known:
1726 assert(klass_id == klass_id_for_intrinsics(method_holder()), "must be");
1727 assert(klass_id != vmSymbolID::NO_SID, "caller responsibility");
1728
1729 // ditto for method and signature:
1730 vmSymbolID name_id = vmSymbols::find_sid(name());
1731 if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1732 && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1733 && name_id == vmSymbolID::NO_SID) {
1734 return;
1735 }
1736 vmSymbolID sig_id = vmSymbols::find_sid(signature());
1737 if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1738 && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1739 && sig_id == vmSymbolID::NO_SID) {
1740 return;
1741 }
1742
1743 u2 flags = access_flags().as_method_flags();
1744 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1745 if (id != vmIntrinsics::_none) {
1746 set_intrinsic_id(id);
1747 if (id == vmIntrinsics::_Class_cast) {
1748 // Even if the intrinsic is rejected, we want to inline this simple method.
1749 set_force_inline();
1750 }
1751 return;
1752 }
1753
1754 // A few slightly irregular cases:
1755 switch (klass_id) {
1756 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1757 case VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1758 case VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1759 if (!is_native()) break;
1760 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1761 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1762 id = vmIntrinsics::_none;
1763 break;
1764
1765 default:
1766 break;
1767 }
1768
1769 if (id != vmIntrinsics::_none) {
1770 // Set up its iid. It is an alias method.
1771 set_intrinsic_id(id);
1772 return;
1773 }
1774 }
1775
1776 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1777 if (!THREAD->can_call_java()) {
1778 // There is nothing useful this routine can do from within the Compile thread.
1779 // Hopefully, the signature contains only well-known classes.
1780 // We could scan for this and return true/false, but the caller won't care.
1781 return false;
1782 }
1783 bool sig_is_loaded = true;
1784 ResourceMark rm(THREAD);
1785 for (ResolvingSignatureStream ss(m()); !ss.is_done(); ss.next()) {
1786 if (ss.is_reference()) {
1787 // load everything, including arrays "[Lfoo;"
1788 Klass* klass = ss.as_klass(SignatureStream::ReturnNull, THREAD);
1789 // We are loading classes eagerly. If a ClassNotFoundException or
1790 // a LinkageError was generated, be sure to ignore it.
1791 if (HAS_PENDING_EXCEPTION) {
1792 if (PENDING_EXCEPTION->is_a(vmClasses::ClassNotFoundException_klass()) ||
1793 PENDING_EXCEPTION->is_a(vmClasses::LinkageError_klass())) {
1794 CLEAR_PENDING_EXCEPTION;
1795 } else {
1796 return false;
1797 }
1798 }
1799 if( klass == nullptr) { sig_is_loaded = false; }
1800 }
1801 }
1802 return sig_is_loaded;
1803 }
1804
1805 // Exposed so field engineers can debug VM
1806 void Method::print_short_name(outputStream* st) const {
1807 ResourceMark rm;
1808 #ifdef PRODUCT
1809 st->print(" %s::", method_holder()->external_name());
1810 #else
1811 st->print(" %s::", method_holder()->internal_name());
1812 #endif
1813 name()->print_symbol_on(st);
1814 if (WizardMode) signature()->print_symbol_on(st);
1815 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1816 MethodHandles::print_as_basic_type_signature_on(st, signature());
1817 }
1818
1819 // Comparer for sorting an object array containing
1820 // Method*s.
1821 static int method_comparator(Method* a, Method* b) {
1822 return a->name()->fast_compare(b->name());
1823 }
1824
1825 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1826 // default_methods also uses this without the ordering for fast find_method
1827 void Method::sort_methods(Array<Method*>* methods, bool set_idnums, method_comparator_func func) {
1828 int length = methods->length();
1829 if (length > 1) {
1830 if (func == nullptr) {
1831 func = method_comparator;
1832 }
1833 {
1834 NoSafepointVerifier nsv;
1835 QuickSort::sort(methods->data(), length, func);
1836 }
1837 // Reset method ordering
1838 if (set_idnums) {
1839 for (u2 i = 0; i < length; i++) {
1840 Method* m = methods->at(i);
1841 m->set_method_idnum(i);
1842 m->set_orig_method_idnum(i);
1843 }
1844 }
1845 }
1846 }
1847
1848 //-----------------------------------------------------------------------------------
1849 // Non-product code unless JVM/TI needs it
1850
1851 #if !defined(PRODUCT) || INCLUDE_JVMTI
1852 class SignatureTypePrinter : public SignatureTypeNames {
1853 private:
1854 outputStream* _st;
1855 bool _use_separator;
1856
1857 void type_name(const char* name) {
1858 if (_use_separator) _st->print(", ");
1859 _st->print("%s", name);
1860 _use_separator = true;
1861 }
1862
1863 public:
1864 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1865 _st = st;
1866 _use_separator = false;
1867 }
1868
1869 void print_parameters() { _use_separator = false; do_parameters_on(this); }
1870 void print_returntype() { _use_separator = false; do_type(return_type()); }
1871 };
1872
1873
1874 void Method::print_name(outputStream* st) const {
1875 Thread *thread = Thread::current();
1876 ResourceMark rm(thread);
1877 st->print("%s ", is_static() ? "static" : "virtual");
1878 if (WizardMode) {
1879 st->print("%s.", method_holder()->internal_name());
1880 name()->print_symbol_on(st);
1881 signature()->print_symbol_on(st);
1882 } else {
1883 SignatureTypePrinter sig(signature(), st);
1884 sig.print_returntype();
1885 st->print(" %s.", method_holder()->internal_name());
1886 name()->print_symbol_on(st);
1887 st->print("(");
1888 sig.print_parameters();
1889 st->print(")");
1890 }
1891 }
1892 #endif // !PRODUCT || INCLUDE_JVMTI
1893
1894
1895 void Method::print_codes_on(outputStream* st, int flags) const {
1896 print_codes_on(0, code_size(), st, flags);
1897 }
1898
1899 void Method::print_codes_on(int from, int to, outputStream* st, int flags) const {
1900 Thread *thread = Thread::current();
1901 ResourceMark rm(thread);
1902 methodHandle mh (thread, (Method*)this);
1903 BytecodeTracer::print_method_codes(mh, from, to, st, flags);
1904 }
1905
1906 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1907 _bci = 0;
1908 _line = 0;
1909 };
1910
1911 bool CompressedLineNumberReadStream::read_pair() {
1912 jubyte next = read_byte();
1913 // Check for terminator
1914 if (next == 0) return false;
1915 if (next == 0xFF) {
1916 // Escape character, regular compression used
1917 _bci += read_signed_int();
1918 _line += read_signed_int();
1919 } else {
1920 // Single byte compression used
1921 _bci += next >> 3;
1922 _line += next & 0x7;
1923 }
1924 return true;
1925 }
1926
1927 #if INCLUDE_JVMTI
1928
1929 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1930 BreakpointInfo* bp = method_holder()->breakpoints();
1931 for (; bp != nullptr; bp = bp->next()) {
1932 if (bp->match(this, bci)) {
1933 return bp->orig_bytecode();
1934 }
1935 }
1936 {
1937 ResourceMark rm;
1938 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1939 }
1940 return Bytecodes::_shouldnotreachhere;
1941 }
1942
1943 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1944 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1945 BreakpointInfo* bp = method_holder()->breakpoints();
1946 for (; bp != nullptr; bp = bp->next()) {
1947 if (bp->match(this, bci)) {
1948 bp->set_orig_bytecode(code);
1949 // and continue, in case there is more than one
1950 }
1951 }
1952 }
1953
1954 void Method::set_breakpoint(int bci) {
1955 InstanceKlass* ik = method_holder();
1956 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1957 bp->set_next(ik->breakpoints());
1958 ik->set_breakpoints(bp);
1959 // do this last:
1960 bp->set(this);
1961 }
1962
1963 static void clear_matches(Method* m, int bci) {
1964 InstanceKlass* ik = m->method_holder();
1965 BreakpointInfo* prev_bp = nullptr;
1966 BreakpointInfo* next_bp;
1967 for (BreakpointInfo* bp = ik->breakpoints(); bp != nullptr; bp = next_bp) {
1968 next_bp = bp->next();
1969 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1970 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1971 // do this first:
1972 bp->clear(m);
1973 // unhook it
1974 if (prev_bp != nullptr)
1975 prev_bp->set_next(next_bp);
1976 else
1977 ik->set_breakpoints(next_bp);
1978 delete bp;
1979 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1980 // at same location. So we have multiple matching (method_index and bci)
1981 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1982 // breakpoint for clear_breakpoint request and keep all other method versions
1983 // BreakpointInfo for future clear_breakpoint request.
1984 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1985 // which is being called when class is unloaded. We delete all the Breakpoint
1986 // information for all versions of method. We may not correctly restore the original
1987 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1988 // so these methods won't be used anymore.
1989 if (bci >= 0) {
1990 break;
1991 }
1992 } else {
1993 // This one is a keeper.
1994 prev_bp = bp;
1995 }
1996 }
1997 }
1998
1999 void Method::clear_breakpoint(int bci) {
2000 assert(bci >= 0, "");
2001 clear_matches(this, bci);
2002 }
2003
2004 void Method::clear_all_breakpoints() {
2005 clear_matches(this, -1);
2006 }
2007
2008 #endif // INCLUDE_JVMTI
2009
2010 int Method::highest_osr_comp_level() const {
2011 const MethodCounters* mcs = method_counters();
2012 if (mcs != nullptr) {
2013 return mcs->highest_osr_comp_level();
2014 } else {
2015 return CompLevel_none;
2016 }
2017 }
2018
2019 void Method::set_highest_comp_level(int level) {
2020 MethodCounters* mcs = method_counters();
2021 if (mcs != nullptr) {
2022 mcs->set_highest_comp_level(level);
2023 }
2024 }
2025
2026 void Method::set_highest_osr_comp_level(int level) {
2027 MethodCounters* mcs = method_counters();
2028 if (mcs != nullptr) {
2029 mcs->set_highest_osr_comp_level(level);
2030 }
2031 }
2032
2033 #if INCLUDE_JVMTI
2034
2035 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
2036 _bci = bci;
2037 _name_index = m->name_index();
2038 _signature_index = m->signature_index();
2039 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
2040 if (_orig_bytecode == Bytecodes::_breakpoint)
2041 _orig_bytecode = m->orig_bytecode_at(_bci);
2042 _next = nullptr;
2043 }
2044
2045 void BreakpointInfo::set(Method* method) {
2046 #ifdef ASSERT
2047 {
2048 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
2049 if (code == Bytecodes::_breakpoint)
2050 code = method->orig_bytecode_at(_bci);
2051 assert(orig_bytecode() == code, "original bytecode must be the same");
2052 }
2053 #endif
2054 Thread *thread = Thread::current();
2055 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2056 method->incr_number_of_breakpoints(thread);
2057 {
2058 // Deoptimize all dependents on this method
2059 HandleMark hm(thread);
2060 methodHandle mh(thread, method);
2061 CodeCache::mark_dependents_on_method_for_breakpoint(mh);
2062 }
2063 }
2064
2065 void BreakpointInfo::clear(Method* method) {
2066 *method->bcp_from(_bci) = orig_bytecode();
2067 assert(method->number_of_breakpoints() > 0, "must not go negative");
2068 method->decr_number_of_breakpoints(Thread::current());
2069 }
2070
2071 #endif // INCLUDE_JVMTI
2072
2073 // jmethodID handling
2074 // jmethodIDs are 64-bit integers that will never run out and are mapped in a table
2075 // to their Method and vice versa. If JNI code has access to stale jmethodID, this
2076 // wastes no memory but the Method* returned is null.
2077
2078 // Add a method id to the jmethod_ids
2079 jmethodID Method::make_jmethod_id(ClassLoaderData* cld, Method* m) {
2080 // Have to add jmethod_ids() to class loader data thread-safely.
2081 // Also have to add the method to the InstanceKlass list safely, which the lock
2082 // protects as well.
2083 assert(JmethodIdCreation_lock->owned_by_self(), "sanity check");
2084 jmethodID jmid = JmethodIDTable::make_jmethod_id(m);
2085 assert(jmid != nullptr, "must be created");
2086
2087 // Add to growable array in CLD.
2088 cld->add_jmethod_id(jmid);
2089 return jmid;
2090 }
2091
2092 // This looks in the InstanceKlass cache, then calls back to make_jmethod_id if not found.
2093 jmethodID Method::jmethod_id() {
2094 return method_holder()->get_jmethod_id(this);
2095 }
2096
2097 // Get the Method out of the table given the method id.
2098 Method* Method::resolve_jmethod_id(jmethodID mid) {
2099 assert(mid != nullptr, "JNI method id should not be null");
2100 return JmethodIDTable::resolve_jmethod_id(mid);
2101 }
2102
2103 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2104 // Can't assert the method_holder is the same because the new method has the
2105 // scratch method holder.
2106 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2107 == new_method->method_holder()->class_loader() ||
2108 new_method->method_holder()->class_loader() == nullptr, // allow substitution to Unsafe method
2109 "changing to a different class loader");
2110 JmethodIDTable::change_method_associated_with_jmethod_id(jmid, new_method);
2111 }
2112
2113 // If there's a jmethodID for this method, clear the Method
2114 // but leave jmethodID for this method in the table.
2115 // It's deallocated with class unloading.
2116 void Method::clear_jmethod_id() {
2117 jmethodID mid = method_holder()->jmethod_id_or_null(this);
2118 if (mid != nullptr) {
2119 JmethodIDTable::clear_jmethod_id(mid, this);
2120 }
2121 }
2122
2123 bool Method::validate_jmethod_id(jmethodID mid) {
2124 Method* m = resolve_jmethod_id(mid);
2125 assert(m != nullptr, "should be called with non-null method");
2126 InstanceKlass* ik = m->method_holder();
2127 ClassLoaderData* cld = ik->class_loader_data();
2128 if (cld->jmethod_ids() == nullptr) return false;
2129 return (cld->jmethod_ids()->contains(mid));
2130 }
2131
2132 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2133 if (mid == nullptr) return nullptr;
2134 Method* o = resolve_jmethod_id(mid);
2135 if (o == nullptr) {
2136 return nullptr;
2137 }
2138 // Method should otherwise be valid. Assert for testing.
2139 assert(is_valid_method(o), "should be valid jmethodid");
2140 // If the method's class holder object is unreferenced, but not yet marked as
2141 // unloaded, we need to return null here too because after a safepoint, its memory
2142 // will be reclaimed.
2143 return o->method_holder()->is_loader_alive() ? o : nullptr;
2144 }
2145
2146 void Method::set_on_stack(const bool value) {
2147 // Set both the method itself and its constant pool. The constant pool
2148 // on stack means some method referring to it is also on the stack.
2149 constants()->set_on_stack(value);
2150
2151 bool already_set = on_stack_flag();
2152 set_on_stack_flag(value);
2153 if (value && !already_set) {
2154 MetadataOnStackMark::record(this);
2155 }
2156 }
2157
2158 void Method::record_gc_epoch() {
2159 // If any method is on the stack in continuations, none of them can be reclaimed,
2160 // so save the marking cycle to check for the whole class in the cpCache.
2161 // The cpCache is writeable.
2162 constants()->cache()->record_gc_epoch();
2163 }
2164
2165 bool Method::has_method_vptr(const void* ptr) {
2166 Method m;
2167 // This assumes that the vtbl pointer is the first word of a C++ object.
2168 return dereference_vptr(&m) == dereference_vptr(ptr);
2169 }
2170
2171 // Check that this pointer is valid by checking that the vtbl pointer matches
2172 bool Method::is_valid_method(const Method* m) {
2173 if (m == nullptr) {
2174 return false;
2175 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2176 // Quick sanity check on pointer.
2177 return false;
2178 } else if (!os::is_readable_range(m, m + 1)) {
2179 return false;
2180 } else if (m->in_aot_cache()) {
2181 return CppVtables::is_valid_shared_method(m);
2182 } else if (Metaspace::contains_non_shared(m)) {
2183 return has_method_vptr((const void*)m);
2184 } else {
2185 return false;
2186 }
2187 }
2188
2189 // Printing
2190
2191 #ifndef PRODUCT
2192
2193 void Method::print_on(outputStream* st) const {
2194 ResourceMark rm;
2195 assert(is_method(), "must be method");
2196 st->print_cr("%s", internal_name());
2197 st->print_cr(" - this oop: " PTR_FORMAT, p2i(this));
2198 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2199 st->print (" - constants: " PTR_FORMAT " ", p2i(constants()));
2200 constants()->print_value_on(st); st->cr();
2201 st->print (" - access: 0x%x ", access_flags().as_method_flags()); access_flags().print_on(st); st->cr();
2202 st->print (" - flags: 0x%x ", _flags.as_int()); _flags.print_on(st); st->cr();
2203 st->print (" - name: "); name()->print_value_on(st); st->cr();
2204 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2205 st->print_cr(" - max stack: %d", max_stack());
2206 st->print_cr(" - max locals: %d", max_locals());
2207 st->print_cr(" - size of params: %d", size_of_parameters());
2208 st->print_cr(" - method size: %d", method_size());
2209 if (intrinsic_id() != vmIntrinsics::_none)
2210 st->print_cr(" - intrinsic id: %d %s", vmIntrinsics::as_int(intrinsic_id()), vmIntrinsics::name_at(intrinsic_id()));
2211 if (highest_comp_level() != CompLevel_none)
2212 st->print_cr(" - highest level: %d", highest_comp_level());
2213 st->print_cr(" - vtable index: %d", _vtable_index);
2214 st->print_cr(" - i2i entry: " PTR_FORMAT, p2i(interpreter_entry()));
2215 st->print( " - adapters: ");
2216 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2217 if (a == nullptr)
2218 st->print_cr(PTR_FORMAT, p2i(a));
2219 else
2220 a->print_adapter_on(st);
2221 st->print_cr(" - compiled entry " PTR_FORMAT, p2i(from_compiled_entry()));
2222 st->print_cr(" - code size: %d", code_size());
2223 if (code_size() != 0) {
2224 st->print_cr(" - code start: " PTR_FORMAT, p2i(code_base()));
2225 st->print_cr(" - code end (excl): " PTR_FORMAT, p2i(code_base() + code_size()));
2226 }
2227 if (method_data() != nullptr) {
2228 st->print_cr(" - method data: " PTR_FORMAT, p2i(method_data()));
2229 }
2230 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2231 if (checked_exceptions_length() > 0) {
2232 CheckedExceptionElement* table = checked_exceptions_start();
2233 st->print_cr(" - checked ex start: " PTR_FORMAT, p2i(table));
2234 if (Verbose) {
2235 for (int i = 0; i < checked_exceptions_length(); i++) {
2236 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2237 }
2238 }
2239 }
2240 if (has_linenumber_table()) {
2241 u_char* table = compressed_linenumber_table();
2242 st->print_cr(" - linenumber start: " PTR_FORMAT, p2i(table));
2243 if (Verbose) {
2244 CompressedLineNumberReadStream stream(table);
2245 while (stream.read_pair()) {
2246 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2247 }
2248 }
2249 }
2250 st->print_cr(" - localvar length: %d", localvariable_table_length());
2251 if (localvariable_table_length() > 0) {
2252 LocalVariableTableElement* table = localvariable_table_start();
2253 st->print_cr(" - localvar start: " PTR_FORMAT, p2i(table));
2254 if (Verbose) {
2255 for (int i = 0; i < localvariable_table_length(); i++) {
2256 int bci = table[i].start_bci;
2257 int len = table[i].length;
2258 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2259 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2260 int slot = table[i].slot;
2261 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2262 }
2263 }
2264 }
2265 if (code() != nullptr) {
2266 st->print (" - compiled code: ");
2267 code()->print_value_on(st);
2268 }
2269 if (is_native()) {
2270 st->print_cr(" - native function: " PTR_FORMAT, p2i(native_function()));
2271 st->print_cr(" - signature handler: " PTR_FORMAT, p2i(signature_handler()));
2272 }
2273 }
2274
2275 void Method::print_linkage_flags(outputStream* st) {
2276 access_flags().print_on(st);
2277 if (is_default_method()) {
2278 st->print("default ");
2279 }
2280 if (is_overpass()) {
2281 st->print("overpass ");
2282 }
2283 }
2284 #endif //PRODUCT
2285
2286 void Method::print_value_on(outputStream* st) const {
2287 assert(is_method(), "must be method");
2288 st->print("%s", internal_name());
2289 print_address_on(st);
2290 st->print(" ");
2291 name()->print_value_on(st);
2292 st->print(" ");
2293 signature()->print_value_on(st);
2294 st->print(" in ");
2295 method_holder()->print_value_on(st);
2296 if (WizardMode) st->print("#%d", _vtable_index);
2297 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2298 if (WizardMode && code() != nullptr) st->print(" ((nmethod*)%p)", code());
2299 }
2300
2301 // Verification
2302
2303 void Method::verify_on(outputStream* st) {
2304 guarantee(is_method(), "object must be method");
2305 guarantee(constants()->is_constantPool(), "should be constant pool");
2306 MethodData* md = method_data();
2307 guarantee(md == nullptr ||
2308 md->is_methodData(), "should be method data");
2309 }