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/cdsConfig.hpp"
26 #include "cds/cppVtables.hpp"
27 #include "cds/metaspaceShared.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/bytecodeStream.hpp"
40 #include "interpreter/bytecodeTracer.hpp"
41 #include "interpreter/bytecodes.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/constMethod.hpp"
55 #include "oops/constantPool.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/inlineKlass.inline.hpp"
65 #include "oops/trainingData.hpp"
66 #include "prims/jvmtiExport.hpp"
67 #include "prims/methodHandles.hpp"
68 #include "runtime/atomic.hpp"
69 #include "runtime/arguments.hpp"
70 #include "runtime/continuationEntry.hpp"
71 #include "runtime/frame.inline.hpp"
72 #include "runtime/handles.inline.hpp"
73 #include "runtime/init.hpp"
74 #include "runtime/java.hpp"
75 #include "runtime/orderAccess.hpp"
76 #include "runtime/perfData.hpp"
77 #include "runtime/relocator.hpp"
78 #include "runtime/safepointVerifiers.hpp"
79 #include "runtime/sharedRuntime.hpp"
80 #include "runtime/signature.hpp"
81 #include "runtime/threads.hpp"
82 #include "runtime/vm_version.hpp"
83 #include "utilities/align.hpp"
84 #include "utilities/quickSort.hpp"
85 #include "utilities/vmError.hpp"
86 #include "utilities/xmlstream.hpp"
87
88 // Implementation of Method
89
90 Method* Method::allocate(ClassLoaderData* loader_data,
91 int byte_code_size,
92 AccessFlags access_flags,
93 InlineTableSizes* sizes,
94 ConstMethod::MethodType method_type,
95 Symbol* name,
96 TRAPS) {
97 assert(!access_flags.is_native() || byte_code_size == 0,
98 "native methods should not contain byte codes");
99 ConstMethod* cm = ConstMethod::allocate(loader_data,
100 byte_code_size,
101 sizes,
102 method_type,
103 CHECK_NULL);
104 int size = Method::size(access_flags.is_native());
105 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags, name);
106 }
107
108 Method::Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name) {
109 NoSafepointVerifier no_safepoint;
110 set_constMethod(xconst);
111 set_access_flags(access_flags);
112 set_intrinsic_id(vmIntrinsics::_none);
113 clear_method_data();
114 clear_method_counters();
115 set_vtable_index(Method::garbage_vtable_index);
116
117 // Fix and bury in Method*
118 set_interpreter_entry(nullptr); // sets i2i entry and from_int
119 set_adapter_entry(nullptr);
120 Method::clear_code(); // from_c/from_i get set to c2i/i2i
121
122 if (access_flags.is_native()) {
123 clear_native_function();
124 set_signature_handler(nullptr);
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 assert(adapter() != nullptr, "must have");
156 return adapter()->get_i2c_entry();
157 }
158
159 address Method::get_c2i_entry() {
160 assert(adapter() != nullptr, "must have");
161 return adapter()->get_c2i_entry();
162 }
163
164 address Method::get_c2i_inline_entry() {
165 assert(adapter() != nullptr, "must have");
166 return adapter()->get_c2i_inline_entry();
167 }
168
169 address Method::get_c2i_unverified_entry() {
170 assert(adapter() != nullptr, "must have");
171 return adapter()->get_c2i_unverified_entry();
172 }
173
174 address Method::get_c2i_unverified_inline_entry() {
175 assert(adapter() != nullptr, "must have");
176 return adapter()->get_c2i_unverified_inline_entry();
177 }
178
179 address Method::get_c2i_no_clinit_check_entry() {
180 assert(VM_Version::supports_fast_class_init_checks(), "");
181 assert(adapter() != nullptr, "must have");
182 return adapter()->get_c2i_no_clinit_check_entry();
183 }
184
185 char* Method::name_and_sig_as_C_string() const {
186 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
187 }
188
189 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
190 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
191 }
192
193 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
194 const char* klass_name = klass->external_name();
195 int klass_name_len = (int)strlen(klass_name);
196 int method_name_len = method_name->utf8_length();
197 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
198 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
199 strcpy(dest, klass_name);
200 dest[klass_name_len] = '.';
201 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
202 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
203 dest[len] = 0;
204 return dest;
205 }
206
207 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
208 Symbol* klass_name = klass->name();
209 klass_name->as_klass_external_name(buf, size);
210 int len = (int)strlen(buf);
211
212 if (len < size - 1) {
213 buf[len++] = '.';
214
215 method_name->as_C_string(&(buf[len]), size - len);
216 len = (int)strlen(buf);
217
218 signature->as_C_string(&(buf[len]), size - len);
219 }
220
221 return buf;
222 }
223
224 const char* Method::external_name() const {
225 return external_name(constants()->pool_holder(), name(), signature());
226 }
227
228 void Method::print_external_name(outputStream *os) const {
229 print_external_name(os, constants()->pool_holder(), name(), signature());
230 }
231
232 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
233 stringStream ss;
234 print_external_name(&ss, klass, method_name, signature);
235 return ss.as_string();
236 }
237
238 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
239 signature->print_as_signature_external_return_type(os);
240 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
241 signature->print_as_signature_external_parameters(os);
242 os->print(")");
243 }
244
245 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
246 if (log_is_enabled(Debug, exceptions)) {
247 ResourceMark rm(THREAD);
248 log_debug(exceptions)("Looking for catch handler for exception of type \"%s\" in method \"%s\"",
249 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string());
250 }
251 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
252 // access exception table
253 ExceptionTable table(mh());
254 int length = table.length();
255 // iterate through all entries sequentially
256 constantPoolHandle pool(THREAD, mh->constants());
257 for (int i = 0; i < length; i ++) {
258 //reacquire the table in case a GC happened
259 ExceptionTable table(mh());
260 int beg_bci = table.start_pc(i);
261 int end_bci = table.end_pc(i);
262 assert(beg_bci <= end_bci, "inconsistent exception table");
263 log_debug(exceptions)(" - checking exception table entry for BCI %d to %d",
264 beg_bci, end_bci);
265
266 if (beg_bci <= throw_bci && throw_bci < end_bci) {
267 // exception handler bci range covers throw_bci => investigate further
268 log_debug(exceptions)(" - entry covers throw point BCI %d", throw_bci);
269
270 int handler_bci = table.handler_pc(i);
271 int klass_index = table.catch_type_index(i);
272 if (klass_index == 0) {
273 if (log_is_enabled(Info, exceptions)) {
274 ResourceMark rm(THREAD);
275 log_info(exceptions)("Found catch-all handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
276 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
277 }
278 return handler_bci;
279 } else if (ex_klass == nullptr) {
280 // Is this even possible?
281 if (log_is_enabled(Info, exceptions)) {
282 ResourceMark rm(THREAD);
283 log_info(exceptions)("null exception class is implicitly caught by handler in method \"%s\" at BCI: %d",
284 mh()->name()->as_C_string(), handler_bci);
285 }
286 return handler_bci;
287 } else {
288 if (log_is_enabled(Debug, exceptions)) {
289 ResourceMark rm(THREAD);
290 log_debug(exceptions)(" - resolving catch type \"%s\"",
291 pool->klass_name_at(klass_index)->as_C_string());
292 }
293 // we know the exception class => get the constraint class
294 // this may require loading of the constraint class; if verification
295 // fails or some other exception occurs, return handler_bci
296 Klass* k = pool->klass_at(klass_index, THREAD);
297 if (HAS_PENDING_EXCEPTION) {
298 if (log_is_enabled(Debug, exceptions)) {
299 ResourceMark rm(THREAD);
300 log_debug(exceptions)(" - exception \"%s\" occurred resolving catch type",
301 PENDING_EXCEPTION->klass()->external_name());
302 }
303 return handler_bci;
304 }
305 assert(k != nullptr, "klass not loaded");
306 if (ex_klass->is_subtype_of(k)) {
307 if (log_is_enabled(Info, exceptions)) {
308 ResourceMark rm(THREAD);
309 log_info(exceptions)("Found matching handler for exception of type \"%s\" in method \"%s\" at BCI: %d",
310 ex_klass == nullptr ? "null" : ex_klass->external_name(), mh->name()->as_C_string(), handler_bci);
311 }
312 return handler_bci;
313 }
314 }
315 }
316 }
317
318 if (log_is_enabled(Debug, exceptions)) {
319 ResourceMark rm(THREAD);
320 log_debug(exceptions)("No catch handler found for exception of type \"%s\" in method \"%s\"",
321 ex_klass->external_name(), mh->name()->as_C_string());
322 }
323
324 return -1;
325 }
326
327 void Method::mask_for(int bci, InterpreterOopMap* mask) {
328 methodHandle h_this(Thread::current(), this);
329 mask_for(h_this, bci, mask);
330 }
331
332 void Method::mask_for(const methodHandle& this_mh, int bci, InterpreterOopMap* mask) {
333 assert(this_mh() == this, "Sanity");
334 method_holder()->mask_for(this_mh, bci, mask);
335 }
336
337 int Method::bci_from(address bcp) const {
338 if (is_native() && bcp == nullptr) {
339 return 0;
340 }
341 // Do not have a ResourceMark here because AsyncGetCallTrace stack walking code
342 // may call this after interrupting a nested ResourceMark.
343 assert((is_native() && bcp == code_base()) || contains(bcp) || VMError::is_error_reported(),
344 "bcp doesn't belong to this method. bcp: " PTR_FORMAT, p2i(bcp));
345
346 return int(bcp - code_base());
347 }
348
349
350 int Method::validate_bci(int bci) const {
351 // Called from the verifier, and should return -1 if not valid.
352 return ((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size())) ? bci : -1;
353 }
354
355 // Return bci if it appears to be a valid bcp
356 // Return -1 otherwise.
357 // Used by profiling code, when invalid data is a possibility.
358 // The caller is responsible for validating the Method* itself.
359 int Method::validate_bci_from_bcp(address bcp) const {
360 // keep bci as -1 if not a valid bci
361 int bci = -1;
362 if (bcp == nullptr || bcp == code_base()) {
363 // code_size() may return 0 and we allow 0 here
364 // the method may be native
365 bci = 0;
366 } else if (contains(bcp)) {
367 bci = int(bcp - code_base());
368 }
369 // Assert that if we have dodged any asserts, bci is negative.
370 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
371 return bci;
372 }
373
374 address Method::bcp_from(int bci) const {
375 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
376 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
377 address bcp = code_base() + bci;
378 assert((is_native() && bcp == code_base()) || contains(bcp), "bcp doesn't belong to this method");
379 return bcp;
380 }
381
382 address Method::bcp_from(address bcp) const {
383 if (is_native() && bcp == nullptr) {
384 return code_base();
385 } else {
386 return bcp;
387 }
388 }
389
390 int Method::size(bool is_native) {
391 // If native, then include pointers for native_function and signature_handler
392 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
393 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
394 return align_metadata_size(header_size() + extra_words);
395 }
396
397 Symbol* Method::klass_name() const {
398 return method_holder()->name();
399 }
400
401 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
402 log_trace(aot)("Iter(Method): %p", this);
403
404 if (!method_holder()->is_rewritten() || CDSConfig::is_valhalla_preview()) {
405 it->push(&_constMethod, MetaspaceClosure::_writable);
406 } else {
407 it->push(&_constMethod);
408 }
409 it->push(&_adapter);
410 it->push(&_method_data);
411 it->push(&_method_counters);
412 NOT_PRODUCT(it->push(&_name);)
413 }
414
415 #if INCLUDE_CDS
416 // Attempt to return method to original state. Clear any pointers
417 // (to objects outside the shared spaces). We won't be able to predict
418 // where they should point in a new JVM. Further initialize some
419 // entries now in order allow them to be write protected later.
420
421 void Method::remove_unshareable_info() {
422 unlink_method();
423 if (method_data() != nullptr) {
424 method_data()->remove_unshareable_info();
425 }
426 if (method_counters() != nullptr) {
427 method_counters()->remove_unshareable_info();
428 }
429 if (CDSConfig::is_dumping_adapters() && _adapter != nullptr) {
430 _adapter->remove_unshareable_info();
431 _adapter = nullptr;
432 }
433 JFR_ONLY(REMOVE_METHOD_ID(this);)
434 }
435
436 void Method::restore_unshareable_info(TRAPS) {
437 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
438 if (method_data() != nullptr) {
439 method_data()->restore_unshareable_info(CHECK);
440 }
441 if (method_counters() != nullptr) {
442 method_counters()->restore_unshareable_info(CHECK);
443 }
444 if (_adapter != nullptr) {
445 assert(_adapter->is_linked(), "must be");
446 _from_compiled_entry = _adapter->get_c2i_entry();
447 _from_compiled_inline_entry = _adapter->get_c2i_inline_entry();
448 _from_compiled_inline_ro_entry = _adapter->get_c2i_inline_ro_entry();
449 }
450 assert(!queued_for_compilation(), "method's queued_for_compilation flag should not be set");
451 }
452 #endif
453
454 void Method::set_vtable_index(int index) {
455 if (is_shared() && !MetaspaceShared::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
456 // At runtime initialize_vtable is rerun as part of link_class_impl()
457 // for a shared class loaded by the non-boot loader to obtain the loader
458 // constraints based on the runtime classloaders' context.
459 return; // don't write into the shared class
460 } else {
461 _vtable_index = index;
462 }
463 }
464
465 void Method::set_itable_index(int index) {
466 if (is_shared() && !MetaspaceShared::remapped_readwrite() && method_holder()->verified_at_dump_time()) {
467 // At runtime initialize_itable is rerun as part of link_class_impl()
468 // for a shared class loaded by the non-boot loader to obtain the loader
469 // constraints based on the runtime classloaders' context. The dumptime
470 // itable index should be the same as the runtime index.
471 assert(_vtable_index == itable_index_max - index,
472 "archived itable index is different from runtime index");
473 return; // don't write into the shared class
474 } else {
475 _vtable_index = itable_index_max - index;
476 }
477 assert(valid_itable_index(), "");
478 }
479
480 // The RegisterNatives call being attempted tried to register with a method that
481 // is not native. Ask JVM TI what prefixes have been specified. Then check
482 // to see if the native method is now wrapped with the prefixes. See the
483 // SetNativeMethodPrefix(es) functions in the JVM TI Spec for details.
484 static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS) {
485 #if INCLUDE_JVMTI
486 ResourceMark rm(THREAD);
487 Method* method;
488 int name_len = name->utf8_length();
489 char* name_str = name->as_utf8();
490 int prefix_count;
491 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
492 for (int i = 0; i < prefix_count; i++) {
493 char* prefix = prefixes[i];
494 int prefix_len = (int)strlen(prefix);
495
496 // try adding this prefix to the method name and see if it matches another method name
497 int trial_len = name_len + prefix_len;
498 char* trial_name_str = NEW_RESOURCE_ARRAY(char, trial_len + 1);
499 strcpy(trial_name_str, prefix);
500 strcat(trial_name_str, name_str);
501 TempNewSymbol trial_name = SymbolTable::probe(trial_name_str, trial_len);
502 if (trial_name == nullptr) {
503 continue; // no such symbol, so this prefix wasn't used, try the next prefix
504 }
505 method = k->lookup_method(trial_name, signature);
506 if (method == nullptr) {
507 continue; // signature doesn't match, try the next prefix
508 }
509 if (method->is_native()) {
510 method->set_is_prefixed_native();
511 return method; // wahoo, we found a prefixed version of the method, return it
512 }
513 // found as non-native, so prefix is good, add it, probably just need more prefixes
514 name_len = trial_len;
515 name_str = trial_name_str;
516 }
517 #endif // INCLUDE_JVMTI
518 return nullptr; // not found
519 }
520
521 bool Method::register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS) {
522 Method* method = k->lookup_method(name, signature);
523 if (method == nullptr) {
524 ResourceMark rm(THREAD);
525 stringStream st;
526 st.print("Method '");
527 print_external_name(&st, k, name, signature);
528 st.print("' name or signature does not match");
529 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
530 }
531 if (!method->is_native()) {
532 // trying to register to a non-native method, see if a JVM TI agent has added prefix(es)
533 method = find_prefixed_native(k, name, signature, THREAD);
534 if (method == nullptr) {
535 ResourceMark rm(THREAD);
536 stringStream st;
537 st.print("Method '");
538 print_external_name(&st, k, name, signature);
539 st.print("' is not declared as native");
540 THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
541 }
542 }
543
544 if (entry != nullptr) {
545 method->set_native_function(entry, native_bind_event_is_interesting);
546 } else {
547 method->clear_native_function();
548 }
549 if (log_is_enabled(Debug, jni, resolve)) {
550 ResourceMark rm(THREAD);
551 log_debug(jni, resolve)("[Registering JNI native method %s.%s]",
552 method->method_holder()->external_name(),
553 method->name()->as_C_string());
554 }
555 return true;
556 }
557
558 bool Method::was_executed_more_than(int n) {
559 // Invocation counter is reset when the Method* is compiled.
560 // If the method has compiled code we therefore assume it has
561 // be executed more than n times.
562 if (is_accessor() || is_empty_method() || (code() != nullptr)) {
563 // interpreter doesn't bump invocation counter of trivial methods
564 // compiler does not bump invocation counter of compiled methods
565 return true;
566 }
567 else if ((method_counters() != nullptr &&
568 method_counters()->invocation_counter()->carry()) ||
569 (method_data() != nullptr &&
570 method_data()->invocation_counter()->carry())) {
571 // The carry bit is set when the counter overflows and causes
572 // a compilation to occur. We don't know how many times
573 // the counter has been reset, so we simply assume it has
574 // been executed more than n times.
575 return true;
576 } else {
577 return invocation_count() > n;
578 }
579 }
580
581 void Method::print_invocation_count(outputStream* st) {
582 //---< compose+print method return type, klass, name, and signature >---
583 if (is_static()) { st->print("static "); }
584 if (is_final()) { st->print("final "); }
585 if (is_synchronized()) { st->print("synchronized "); }
586 if (is_native()) { st->print("native "); }
587 st->print("%s::", method_holder()->external_name());
588 name()->print_symbol_on(st);
589 signature()->print_symbol_on(st);
590
591 if (WizardMode) {
592 // dump the size of the byte codes
593 st->print(" {%d}", code_size());
594 }
595 st->cr();
596
597 // Counting based on signed int counters tends to overflow with
598 // longer-running workloads on fast machines. The counters under
599 // consideration here, however, are limited in range by counting
600 // logic. See InvocationCounter:count_limit for example.
601 // No "overflow precautions" need to be implemented here.
602 st->print_cr (" interpreter_invocation_count: " INT32_FORMAT_W(11), interpreter_invocation_count());
603 st->print_cr (" invocation_counter: " INT32_FORMAT_W(11), invocation_count());
604 st->print_cr (" backedge_counter: " INT32_FORMAT_W(11), backedge_count());
605
606 if (method_data() != nullptr) {
607 st->print_cr (" decompile_count: " UINT32_FORMAT_W(11), method_data()->decompile_count());
608 }
609
610 #ifndef PRODUCT
611 if (CountCompiledCalls) {
612 st->print_cr (" compiled_invocation_count: " INT64_FORMAT_W(11), compiled_invocation_count());
613 }
614 #endif
615 }
616
617 MethodTrainingData* Method::training_data_or_null() const {
618 MethodCounters* mcs = method_counters();
619 if (mcs == nullptr) {
620 return nullptr;
621 } else {
622 MethodTrainingData* mtd = mcs->method_training_data();
623 if (mtd == mcs->method_training_data_sentinel()) {
624 return nullptr;
625 }
626 return mtd;
627 }
628 }
629
630 bool Method::init_training_data(MethodTrainingData* td) {
631 MethodCounters* mcs = method_counters();
632 if (mcs == nullptr) {
633 return false;
634 } else {
635 return mcs->init_method_training_data(td);
636 }
637 }
638
639 bool Method::install_training_method_data(const methodHandle& method) {
640 MethodTrainingData* mtd = MethodTrainingData::find(method);
641 if (mtd != nullptr && mtd->final_profile() != nullptr) {
642 Atomic::replace_if_null(&method->_method_data, mtd->final_profile());
643 return true;
644 }
645 return false;
646 }
647
648 // Build a MethodData* object to hold profiling information collected on this
649 // method when requested.
650 void Method::build_profiling_method_data(const methodHandle& method, TRAPS) {
651 if (install_training_method_data(method)) {
652 return;
653 }
654 // Do not profile the method if metaspace has hit an OOM previously
655 // allocating profiling data. Callers clear pending exception so don't
656 // add one here.
657 if (ClassLoaderDataGraph::has_metaspace_oom()) {
658 return;
659 }
660
661 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
662 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
663 if (HAS_PENDING_EXCEPTION) {
664 CompileBroker::log_metaspace_failure();
665 ClassLoaderDataGraph::set_metaspace_oom(true);
666 return; // return the exception (which is cleared)
667 }
668
669 if (!Atomic::replace_if_null(&method->_method_data, method_data)) {
670 MetadataFactory::free_metadata(loader_data, method_data);
671 return;
672 }
673
674 if (PrintMethodData && (Verbose || WizardMode)) {
675 ResourceMark rm(THREAD);
676 tty->print("build_profiling_method_data for ");
677 method->print_name(tty);
678 tty->cr();
679 // At the end of the run, the MDO, full of data, will be dumped.
680 }
681 }
682
683 MethodCounters* Method::build_method_counters(Thread* current, Method* m) {
684 // Do not profile the method if metaspace has hit an OOM previously
685 if (ClassLoaderDataGraph::has_metaspace_oom()) {
686 return nullptr;
687 }
688
689 methodHandle mh(current, m);
690 MethodCounters* counters;
691 if (current->is_Java_thread()) {
692 JavaThread* THREAD = JavaThread::cast(current); // For exception macros.
693 // Use the TRAPS version for a JavaThread so it will adjust the GC threshold
694 // if needed.
695 counters = MethodCounters::allocate_with_exception(mh, THREAD);
696 if (HAS_PENDING_EXCEPTION) {
697 CLEAR_PENDING_EXCEPTION;
698 }
699 } else {
700 // Call metaspace allocation that doesn't throw exception if the
701 // current thread isn't a JavaThread, ie. the VMThread.
702 counters = MethodCounters::allocate_no_exception(mh);
703 }
704
705 if (counters == nullptr) {
706 CompileBroker::log_metaspace_failure();
707 ClassLoaderDataGraph::set_metaspace_oom(true);
708 return nullptr;
709 }
710
711 if (!mh->init_method_counters(counters)) {
712 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
713 }
714
715 return mh->method_counters();
716 }
717
718 bool Method::init_method_counters(MethodCounters* counters) {
719 // Try to install a pointer to MethodCounters, return true on success.
720 return Atomic::replace_if_null(&_method_counters, counters);
721 }
722
723 void Method::set_exception_handler_entered(int handler_bci) {
724 if (ProfileExceptionHandlers) {
725 MethodData* mdo = method_data();
726 if (mdo != nullptr) {
727 BitData handler_data = mdo->exception_handler_bci_to_data(handler_bci);
728 handler_data.set_exception_handler_entered();
729 }
730 }
731 }
732
733 int Method::extra_stack_words() {
734 // not an inline function, to avoid a header dependency on Interpreter
735 return extra_stack_entries() * Interpreter::stackElementSize;
736 }
737
738 // InlineKlass the method is declared to return. This must not
739 // safepoint as it is called with references live on the stack at
740 // locations the GC is unaware of.
741 InlineKlass* Method::returns_inline_type() const {
742 assert(InlineTypeReturnedAsFields, "Inline types should never be returned as fields");
743 if (is_native()) {
744 return nullptr;
745 }
746 NoSafepointVerifier nsv;
747 SignatureStream ss(signature());
748 ss.skip_to_return_type();
749 return ss.as_inline_klass(method_holder());
750 }
751
752 bool Method::compute_has_loops_flag() {
753 BytecodeStream bcs(methodHandle(Thread::current(), this));
754 Bytecodes::Code bc;
755
756 while ((bc = bcs.next()) >= 0) {
757 switch (bc) {
758 case Bytecodes::_ifeq:
759 case Bytecodes::_ifnull:
760 case Bytecodes::_iflt:
761 case Bytecodes::_ifle:
762 case Bytecodes::_ifne:
763 case Bytecodes::_ifnonnull:
764 case Bytecodes::_ifgt:
765 case Bytecodes::_ifge:
766 case Bytecodes::_if_icmpeq:
767 case Bytecodes::_if_icmpne:
768 case Bytecodes::_if_icmplt:
769 case Bytecodes::_if_icmpgt:
770 case Bytecodes::_if_icmple:
771 case Bytecodes::_if_icmpge:
772 case Bytecodes::_if_acmpeq:
773 case Bytecodes::_if_acmpne:
774 case Bytecodes::_goto:
775 case Bytecodes::_jsr:
776 if (bcs.dest() < bcs.next_bci()) {
777 return set_has_loops();
778 }
779 break;
780
781 case Bytecodes::_goto_w:
782 case Bytecodes::_jsr_w:
783 if (bcs.dest_w() < bcs.next_bci()) {
784 return set_has_loops();
785 }
786 break;
787
788 case Bytecodes::_lookupswitch: {
789 Bytecode_lookupswitch lookupswitch(this, bcs.bcp());
790 if (lookupswitch.default_offset() < 0) {
791 return set_has_loops();
792 } else {
793 for (int i = 0; i < lookupswitch.number_of_pairs(); ++i) {
794 LookupswitchPair pair = lookupswitch.pair_at(i);
795 if (pair.offset() < 0) {
796 return set_has_loops();
797 }
798 }
799 }
800 break;
801 }
802 case Bytecodes::_tableswitch: {
803 Bytecode_tableswitch tableswitch(this, bcs.bcp());
804 if (tableswitch.default_offset() < 0) {
805 return set_has_loops();
806 } else {
807 for (int i = 0; i < tableswitch.length(); ++i) {
808 if (tableswitch.dest_offset_at(i) < 0) {
809 return set_has_loops();
810 }
811 }
812 }
813 break;
814 }
815 default:
816 break;
817 }
818 }
819
820 _flags.set_has_loops_flag_init(true);
821 return false;
822 }
823
824 bool Method::is_final_method(AccessFlags class_access_flags) const {
825 // or "does_not_require_vtable_entry"
826 // default method or overpass can occur, is not final (reuses vtable entry)
827 // private methods in classes get vtable entries for backward class compatibility.
828 if (is_overpass() || is_default_method()) return false;
829 return is_final() || class_access_flags.is_final();
830 }
831
832 bool Method::is_final_method() const {
833 return is_final_method(method_holder()->access_flags());
834 }
835
836 bool Method::is_default_method() const {
837 if (method_holder() != nullptr &&
838 method_holder()->is_interface() &&
839 !is_abstract() && !is_private()) {
840 return true;
841 } else {
842 return false;
843 }
844 }
845
846 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
847 if (is_final_method(class_access_flags)) return true;
848 #ifdef ASSERT
849 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
850 if (class_access_flags.is_interface()) {
851 ResourceMark rm;
852 assert(is_nonv == is_static() || is_nonv == is_private(),
853 "nonvirtual unexpected for non-static, non-private: %s",
854 name_and_sig_as_C_string());
855 }
856 #endif
857 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
858 return vtable_index() == nonvirtual_vtable_index;
859 }
860
861 bool Method::can_be_statically_bound() const {
862 return can_be_statically_bound(method_holder()->access_flags());
863 }
864
865 bool Method::can_be_statically_bound(InstanceKlass* context) const {
866 return (method_holder() == context) && can_be_statically_bound();
867 }
868
869 /**
870 * Returns false if this is one of specially treated methods for
871 * which we have to provide stack trace in throw in compiled code.
872 * Returns true otherwise.
873 */
874 bool Method::can_omit_stack_trace() {
875 if (klass_name() == vmSymbols::sun_invoke_util_ValueConversions()) {
876 return false; // All methods in sun.invoke.util.ValueConversions
877 }
878 return true;
879 }
880
881 bool Method::is_accessor() const {
882 return is_getter() || is_setter();
883 }
884
885 bool Method::is_getter() const {
886 if (code_size() != 5) return false;
887 if (size_of_parameters() != 1) return false;
888 if (java_code_at(0) != Bytecodes::_aload_0) return false;
889 if (java_code_at(1) != Bytecodes::_getfield) return false;
890 switch (java_code_at(4)) {
891 case Bytecodes::_ireturn:
892 case Bytecodes::_lreturn:
893 case Bytecodes::_freturn:
894 case Bytecodes::_dreturn:
895 case Bytecodes::_areturn:
896 break;
897 default:
898 return false;
899 }
900 if (has_scalarized_return()) {
901 // Don't treat this as (trivial) getter method because the
902 // inline type should be returned in a scalarized form.
903 return false;
904 }
905 return true;
906 }
907
908 bool Method::is_setter() const {
909 if (code_size() != 6) return false;
910 if (java_code_at(0) != Bytecodes::_aload_0) return false;
911 switch (java_code_at(1)) {
912 case Bytecodes::_iload_1:
913 case Bytecodes::_aload_1:
914 case Bytecodes::_fload_1:
915 if (size_of_parameters() != 2) return false;
916 break;
917 case Bytecodes::_dload_1:
918 case Bytecodes::_lload_1:
919 if (size_of_parameters() != 3) return false;
920 break;
921 default:
922 return false;
923 }
924 if (java_code_at(2) != Bytecodes::_putfield) return false;
925 if (java_code_at(5) != Bytecodes::_return) return false;
926 if (has_scalarized_args()) {
927 // Don't treat this as (trivial) setter method because the
928 // inline type argument should be passed in a scalarized form.
929 return false;
930 }
931 return true;
932 }
933
934 bool Method::is_constant_getter() const {
935 int last_index = code_size() - 1;
936 // Check if the first 1-3 bytecodes are a constant push
937 // and the last bytecode is a return.
938 return (2 <= code_size() && code_size() <= 4 &&
939 Bytecodes::is_const(java_code_at(0)) &&
940 Bytecodes::length_for(java_code_at(0)) == last_index &&
941 Bytecodes::is_return(java_code_at(last_index)) &&
942 !has_scalarized_args());
943 }
944
945 bool Method::is_class_initializer() const {
946 // For classfiles version 51 or greater, ensure that the clinit method is
947 // static. Non-static methods with the name "<clinit>" are not static
948 // initializers. (older classfiles exempted for backward compatibility)
949 return (name() == vmSymbols::class_initializer_name() &&
950 (is_static() ||
951 method_holder()->major_version() < 51));
952 }
953
954 // A method named <init>, is a classic object constructor.
955 bool Method::is_object_constructor() const {
956 return name() == vmSymbols::object_initializer_name();
957 }
958
959 bool Method::needs_clinit_barrier() const {
960 return is_static() && !method_holder()->is_initialized();
961 }
962
963 bool Method::is_object_wait0() const {
964 return klass_name() == vmSymbols::java_lang_Object()
965 && name() == vmSymbols::wait_name();
966 }
967
968 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
969 int length = method->checked_exceptions_length();
970 if (length == 0) { // common case
971 return objArrayHandle(THREAD, Universe::the_empty_class_array());
972 } else {
973 methodHandle h_this(THREAD, method);
974 objArrayOop m_oop = oopFactory::new_objArray(vmClasses::Class_klass(), length, CHECK_(objArrayHandle()));
975 objArrayHandle mirrors (THREAD, m_oop);
976 for (int i = 0; i < length; i++) {
977 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
978 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
979 if (log_is_enabled(Warning, exceptions) &&
980 !k->is_subclass_of(vmClasses::Throwable_klass())) {
981 ResourceMark rm(THREAD);
982 log_warning(exceptions)(
983 "Class %s in throws clause of method %s is not a subtype of class java.lang.Throwable",
984 k->external_name(), method->external_name());
985 }
986 mirrors->obj_at_put(i, k->java_mirror());
987 }
988 return mirrors;
989 }
990 };
991
992
993 int Method::line_number_from_bci(int bci) const {
994 int best_bci = 0;
995 int best_line = -1;
996 if (bci == SynchronizationEntryBCI) bci = 0;
997 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
998 // The line numbers are a short array of 2-tuples [start_pc, line_number].
999 // Not necessarily sorted and not necessarily one-to-one.
1000 CompressedLineNumberReadStream stream(compressed_linenumber_table());
1001 while (stream.read_pair()) {
1002 if (stream.bci() == bci) {
1003 // perfect match
1004 return stream.line();
1005 } else {
1006 // update best_bci/line
1007 if (stream.bci() < bci && stream.bci() >= best_bci) {
1008 best_bci = stream.bci();
1009 best_line = stream.line();
1010 }
1011 }
1012 }
1013 }
1014 return best_line;
1015 }
1016
1017
1018 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
1019 if( constants()->tag_at(klass_index).is_unresolved_klass()) {
1020 Thread *thread = Thread::current();
1021 Symbol* klass_name = constants()->klass_name_at(klass_index);
1022 Handle loader(thread, method_holder()->class_loader());
1023 return SystemDictionary::find_instance_klass(thread, klass_name, loader) != nullptr;
1024 } else {
1025 return true;
1026 }
1027 }
1028
1029
1030 bool Method::is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved) const {
1031 int klass_index = constants()->klass_ref_index_at(refinfo_index, bc);
1032 if (must_be_resolved) {
1033 // Make sure klass is resolved in constantpool.
1034 if (constants()->tag_at(klass_index).is_unresolved_klass()) {
1035 return false;
1036 }
1037 }
1038 return is_klass_loaded_by_klass_index(klass_index);
1039 }
1040
1041
1042 void Method::set_native_function(address function, bool post_event_flag) {
1043 assert(function != nullptr, "use clear_native_function to unregister natives");
1044 assert(!is_special_native_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
1045 address* native_function = native_function_addr();
1046
1047 // We can see racers trying to place the same native function into place. Once
1048 // is plenty.
1049 address current = *native_function;
1050 if (current == function) return;
1051 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
1052 function != nullptr) {
1053 // native_method_throw_unsatisfied_link_error_entry() should only
1054 // be passed when post_event_flag is false.
1055 assert(function !=
1056 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1057 "post_event_flag mismatch");
1058
1059 // post the bind event, and possible change the bind function
1060 JvmtiExport::post_native_method_bind(this, &function);
1061 }
1062 *native_function = function;
1063 // This function can be called more than once. We must make sure that we always
1064 // use the latest registered method -> check if a stub already has been generated.
1065 // If so, we have to make it not_entrant.
1066 nmethod* nm = code(); // Put it into local variable to guard against concurrent updates
1067 if (nm != nullptr) {
1068 nm->make_not_entrant(nmethod::InvalidationReason::SET_NATIVE_FUNCTION);
1069 }
1070 }
1071
1072
1073 bool Method::has_native_function() const {
1074 if (is_special_native_intrinsic())
1075 return false; // special-cased in SharedRuntime::generate_native_wrapper
1076 address func = native_function();
1077 return (func != nullptr && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
1078 }
1079
1080
1081 void Method::clear_native_function() {
1082 // Note: is_method_handle_intrinsic() is allowed here.
1083 set_native_function(
1084 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1085 !native_bind_event_is_interesting);
1086 this->unlink_code();
1087 }
1088
1089
1090 void Method::set_signature_handler(address handler) {
1091 address* signature_handler = signature_handler_addr();
1092 *signature_handler = handler;
1093 }
1094
1095
1096 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
1097 assert(reason != nullptr, "must provide a reason");
1098 if (PrintCompilation && report) {
1099 ttyLocker ttyl;
1100 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
1101 if (comp_level == CompLevel_all) {
1102 tty->print("all levels ");
1103 } else {
1104 tty->print("level %d ", comp_level);
1105 }
1106 this->print_short_name(tty);
1107 int size = this->code_size();
1108 if (size > 0) {
1109 tty->print(" (%d bytes)", size);
1110 }
1111 if (reason != nullptr) {
1112 tty->print(" %s", reason);
1113 }
1114 tty->cr();
1115 }
1116 if ((TraceDeoptimization || LogCompilation) && (xtty != nullptr)) {
1117 ttyLocker ttyl;
1118 xtty->begin_elem("make_not_compilable thread='%zu' osr='%d' level='%d'",
1119 os::current_thread_id(), is_osr, comp_level);
1120 if (reason != nullptr) {
1121 xtty->print(" reason=\'%s\'", reason);
1122 }
1123 xtty->method(this);
1124 xtty->stamp();
1125 xtty->end_elem();
1126 }
1127 }
1128
1129 bool Method::is_always_compilable() const {
1130 // Generated adapters must be compiled
1131 if (is_special_native_intrinsic() && is_synthetic()) {
1132 assert(!is_not_c1_compilable(), "sanity check");
1133 assert(!is_not_c2_compilable(), "sanity check");
1134 return true;
1135 }
1136
1137 return false;
1138 }
1139
1140 bool Method::is_not_compilable(int comp_level) const {
1141 if (number_of_breakpoints() > 0)
1142 return true;
1143 if (is_always_compilable())
1144 return false;
1145 if (comp_level == CompLevel_any)
1146 return is_not_c1_compilable() && is_not_c2_compilable();
1147 if (is_c1_compile(comp_level))
1148 return is_not_c1_compilable();
1149 if (is_c2_compile(comp_level))
1150 return is_not_c2_compilable();
1151 return false;
1152 }
1153
1154 // call this when compiler finds that this method is not compilable
1155 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
1156 if (is_always_compilable()) {
1157 // Don't mark a method which should be always compilable
1158 return;
1159 }
1160 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
1161 if (comp_level == CompLevel_all) {
1162 set_is_not_c1_compilable();
1163 set_is_not_c2_compilable();
1164 } else {
1165 if (is_c1_compile(comp_level))
1166 set_is_not_c1_compilable();
1167 if (is_c2_compile(comp_level))
1168 set_is_not_c2_compilable();
1169 }
1170 assert(!CompilationPolicy::can_be_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1171 }
1172
1173 bool Method::is_not_osr_compilable(int comp_level) const {
1174 if (is_not_compilable(comp_level))
1175 return true;
1176 if (comp_level == CompLevel_any)
1177 return is_not_c1_osr_compilable() && is_not_c2_osr_compilable();
1178 if (is_c1_compile(comp_level))
1179 return is_not_c1_osr_compilable();
1180 if (is_c2_compile(comp_level))
1181 return is_not_c2_osr_compilable();
1182 return false;
1183 }
1184
1185 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
1186 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
1187 if (comp_level == CompLevel_all) {
1188 set_is_not_c1_osr_compilable();
1189 set_is_not_c2_osr_compilable();
1190 } else {
1191 if (is_c1_compile(comp_level))
1192 set_is_not_c1_osr_compilable();
1193 if (is_c2_compile(comp_level))
1194 set_is_not_c2_osr_compilable();
1195 }
1196 assert(!CompilationPolicy::can_be_osr_compiled(methodHandle(Thread::current(), this), comp_level), "sanity check");
1197 }
1198
1199 // Revert to using the interpreter and clear out the nmethod
1200 void Method::clear_code() {
1201 // this may be null if c2i adapters have not been made yet
1202 // Only should happen at allocate time.
1203 if (adapter() == nullptr) {
1204 _from_compiled_entry = nullptr;
1205 _from_compiled_inline_entry = nullptr;
1206 _from_compiled_inline_ro_entry = nullptr;
1207 } else {
1208 _from_compiled_entry = adapter()->get_c2i_entry();
1209 _from_compiled_inline_entry = adapter()->get_c2i_inline_entry();
1210 _from_compiled_inline_ro_entry = adapter()->get_c2i_inline_ro_entry();
1211 }
1212 OrderAccess::storestore();
1213 _from_interpreted_entry = _i2i_entry;
1214 OrderAccess::storestore();
1215 _code = nullptr;
1216 }
1217
1218 void Method::unlink_code(nmethod *compare) {
1219 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1220 // We need to check if either the _code or _from_compiled_code_entry_point
1221 // refer to this nmethod because there is a race in setting these two fields
1222 // in Method* as seen in bugid 4947125.
1223 if (code() == compare ||
1224 from_compiled_entry() == compare->verified_entry_point()) {
1225 clear_code();
1226 }
1227 }
1228
1229 void Method::unlink_code() {
1230 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
1231 clear_code();
1232 }
1233
1234 #if INCLUDE_CDS
1235 // Called by class data sharing to remove any entry points (which are not shared)
1236 void Method::unlink_method() {
1237 assert(CDSConfig::is_dumping_archive(), "sanity");
1238 _code = nullptr;
1239 if (!CDSConfig::is_dumping_adapters() || AdapterHandlerLibrary::is_abstract_method_adapter(_adapter)) {
1240 _adapter = nullptr;
1241 }
1242 _i2i_entry = nullptr;
1243 _from_compiled_entry = nullptr;
1244 _from_compiled_inline_entry = nullptr;
1245 _from_compiled_inline_ro_entry = nullptr;
1246 _from_interpreted_entry = nullptr;
1247
1248 if (is_native()) {
1249 *native_function_addr() = nullptr;
1250 set_signature_handler(nullptr);
1251 }
1252 NOT_PRODUCT(set_compiled_invocation_count(0);)
1253
1254 clear_method_data();
1255 clear_method_counters();
1256 clear_is_not_c1_compilable();
1257 clear_is_not_c1_osr_compilable();
1258 clear_is_not_c2_compilable();
1259 clear_is_not_c2_osr_compilable();
1260 clear_queued_for_compilation();
1261
1262 remove_unshareable_flags();
1263 }
1264
1265 void Method::remove_unshareable_flags() {
1266 // clear all the flags that shouldn't be in the archived version
1267 assert(!is_old(), "must be");
1268 assert(!is_obsolete(), "must be");
1269 assert(!is_deleted(), "must be");
1270
1271 set_is_prefixed_native(false);
1272 set_queued_for_compilation(false);
1273 set_is_not_c2_compilable(false);
1274 set_is_not_c1_compilable(false);
1275 set_is_not_c2_osr_compilable(false);
1276 set_on_stack_flag(false);
1277 set_has_scalarized_args(false);
1278 set_has_scalarized_return(false);
1279 }
1280 #endif
1281
1282 // Called when the method_holder is getting linked. Setup entrypoints so the method
1283 // is ready to be called from interpreter, compiler, and vtables.
1284 void Method::link_method(const methodHandle& h_method, TRAPS) {
1285 if (log_is_enabled(Info, perf, class, link)) {
1286 ClassLoader::perf_ik_link_methods_count()->inc();
1287 }
1288
1289 // If the code cache is full, we may reenter this function for the
1290 // leftover methods that weren't linked.
1291 if (adapter() != nullptr) {
1292 if (adapter()->is_shared()) {
1293 assert(adapter()->is_linked(), "Adapter is shared but not linked");
1294 } else {
1295 return;
1296 }
1297 }
1298 assert( _code == nullptr, "nothing compiled yet" );
1299
1300 // Setup interpreter entrypoint
1301 assert(this == h_method(), "wrong h_method()" );
1302
1303 assert(adapter() == nullptr || adapter()->is_linked(), "init'd to null or restored from cache");
1304 address entry = Interpreter::entry_for_method(h_method);
1305 assert(entry != nullptr, "interpreter entry must be non-null");
1306 // Sets both _i2i_entry and _from_interpreted_entry
1307 set_interpreter_entry(entry);
1308
1309 // Don't overwrite already registered native entries.
1310 if (is_native() && !has_native_function()) {
1311 set_native_function(
1312 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1313 !native_bind_event_is_interesting);
1314 }
1315 if (InlineTypeReturnedAsFields && returns_inline_type() && !has_scalarized_return()) {
1316 set_has_scalarized_return();
1317 }
1318
1319 // Setup compiler entrypoint. This is made eagerly, so we do not need
1320 // special handling of vtables. An alternative is to make adapters more
1321 // lazily by calling make_adapter() from from_compiled_entry() for the
1322 // normal calls. For vtable calls life gets more complicated. When a
1323 // call-site goes mega-morphic we need adapters in all methods which can be
1324 // called from the vtable. We need adapters on such methods that get loaded
1325 // later. Ditto for mega-morphic itable calls. If this proves to be a
1326 // problem we'll make these lazily later.
1327 if (_adapter == nullptr) {
1328 (void) make_adapters(h_method, CHECK);
1329 assert(adapter()->is_linked(), "Adapter must have been linked");
1330 }
1331
1332 // ONLY USE the h_method now as make_adapter may have blocked
1333
1334 if (h_method->is_continuation_native_intrinsic()) {
1335 _from_interpreted_entry = nullptr;
1336 _from_compiled_entry = nullptr;
1337 _i2i_entry = nullptr;
1338 if (Continuations::enabled()) {
1339 assert(!Threads::is_vm_complete(), "should only be called during vm init");
1340 AdapterHandlerLibrary::create_native_wrapper(h_method);
1341 if (!h_method->has_compiled_code()) {
1342 THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), "Initial size of CodeCache is too small");
1343 }
1344 assert(_from_interpreted_entry == get_i2c_entry(), "invariant");
1345 }
1346 }
1347 }
1348
1349 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1350 PerfTraceTime timer(ClassLoader::perf_method_adapters_time());
1351
1352 // Adapters for compiled code are made eagerly here. They are fairly
1353 // small (generally < 100 bytes) and quick to make (and cached and shared)
1354 // so making them eagerly shouldn't be too expensive.
1355 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1356 if (adapter == nullptr ) {
1357 if (!is_init_completed()) {
1358 // Don't throw exceptions during VM initialization because java.lang.* classes
1359 // might not have been initialized, causing problems when constructing the
1360 // Java exception object.
1361 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1362 } else {
1363 THROW_MSG_NULL(vmSymbols::java_lang_OutOfMemoryError(), "Out of space in CodeCache for adapters");
1364 }
1365 }
1366
1367 mh->set_adapter_entry(adapter);
1368 mh->_from_compiled_entry = adapter->get_c2i_entry();
1369 mh->_from_compiled_inline_entry = adapter->get_c2i_inline_entry();
1370 mh->_from_compiled_inline_ro_entry = adapter->get_c2i_inline_ro_entry();
1371 return adapter->get_c2i_entry();
1372 }
1373
1374 // The verified_code_entry() must be called when a invoke is resolved
1375 // on this method.
1376
1377 // It returns the compiled code entry point, after asserting not null.
1378 // This function is called after potential safepoints so that nmethod
1379 // or adapter that it points to is still live and valid.
1380 // This function must not hit a safepoint!
1381 address Method::verified_code_entry() {
1382 DEBUG_ONLY(NoSafepointVerifier nsv;)
1383 assert(_from_compiled_entry != nullptr, "must be set");
1384 return _from_compiled_entry;
1385 }
1386
1387 address Method::verified_inline_code_entry() {
1388 DEBUG_ONLY(NoSafepointVerifier nsv;)
1389 assert(_from_compiled_inline_entry != nullptr, "must be set");
1390 return _from_compiled_inline_entry;
1391 }
1392
1393 address Method::verified_inline_ro_code_entry() {
1394 DEBUG_ONLY(NoSafepointVerifier nsv;)
1395 assert(_from_compiled_inline_ro_entry != nullptr, "must be set");
1396 return _from_compiled_inline_ro_entry;
1397 }
1398
1399 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1400 // (could be racing a deopt).
1401 // Not inline to avoid circular ref.
1402 bool Method::check_code() const {
1403 // cached in a register or local. There's a race on the value of the field.
1404 nmethod *code = Atomic::load_acquire(&_code);
1405 return code == nullptr || (code->method() == nullptr) || (code->method() == (Method*)this && !code->is_osr_method());
1406 }
1407
1408 // Install compiled code. Instantly it can execute.
1409 void Method::set_code(const methodHandle& mh, nmethod *code) {
1410 assert_lock_strong(NMethodState_lock);
1411 assert( code, "use clear_code to remove code" );
1412 assert( mh->check_code(), "" );
1413
1414 guarantee(mh->adapter() != nullptr, "Adapter blob must already exist!");
1415
1416 // These writes must happen in this order, because the interpreter will
1417 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1418 // which jumps to _from_compiled_entry.
1419 mh->_code = code; // Assign before allowing compiled code to exec
1420
1421 int comp_level = code->comp_level();
1422 // In theory there could be a race here. In practice it is unlikely
1423 // and not worth worrying about.
1424 if (comp_level > mh->highest_comp_level()) {
1425 mh->set_highest_comp_level(comp_level);
1426 }
1427
1428 OrderAccess::storestore();
1429 mh->_from_compiled_entry = code->verified_entry_point();
1430 mh->_from_compiled_inline_entry = code->verified_inline_entry_point();
1431 mh->_from_compiled_inline_ro_entry = code->verified_inline_ro_entry_point();
1432 OrderAccess::storestore();
1433
1434 if (mh->is_continuation_native_intrinsic()) {
1435 assert(mh->_from_interpreted_entry == nullptr, "initialized incorrectly"); // see link_method
1436
1437 if (mh->is_continuation_enter_intrinsic()) {
1438 // This is the entry used when we're in interpreter-only mode; see InterpreterMacroAssembler::jump_from_interpreted
1439 mh->_i2i_entry = ContinuationEntry::interpreted_entry();
1440 } else if (mh->is_continuation_yield_intrinsic()) {
1441 mh->_i2i_entry = mh->get_i2c_entry();
1442 } else {
1443 guarantee(false, "Unknown Continuation native intrinsic");
1444 }
1445 // This must come last, as it is what's tested in LinkResolver::resolve_static_call
1446 Atomic::release_store(&mh->_from_interpreted_entry , mh->get_i2c_entry());
1447 } else if (!mh->is_method_handle_intrinsic()) {
1448 // Instantly compiled code can execute.
1449 mh->_from_interpreted_entry = mh->get_i2c_entry();
1450 }
1451 }
1452
1453
1454 bool Method::is_overridden_in(Klass* k) const {
1455 InstanceKlass* ik = InstanceKlass::cast(k);
1456
1457 if (ik->is_interface()) return false;
1458
1459 // If method is an interface, we skip it - except if it
1460 // is a miranda method
1461 if (method_holder()->is_interface()) {
1462 // Check that method is not a miranda method
1463 if (ik->lookup_method(name(), signature()) == nullptr) {
1464 // No implementation exist - so miranda method
1465 return false;
1466 }
1467 return true;
1468 }
1469
1470 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1471 if (!has_vtable_index()) {
1472 return false;
1473 } else {
1474 Method* vt_m = ik->method_at_vtable(vtable_index());
1475 return vt_m != this;
1476 }
1477 }
1478
1479
1480 // give advice about whether this Method* should be cached or not
1481 bool Method::should_not_be_cached() const {
1482 if (is_old()) {
1483 // This method has been redefined. It is either EMCP or obsolete
1484 // and we don't want to cache it because that would pin the method
1485 // down and prevent it from being collectible if and when it
1486 // finishes executing.
1487 return true;
1488 }
1489
1490 // caching this method should be just fine
1491 return false;
1492 }
1493
1494
1495 /**
1496 * Returns true if this is one of the specially treated methods for
1497 * security related stack walks (like Reflection.getCallerClass).
1498 */
1499 bool Method::is_ignored_by_security_stack_walk() const {
1500 if (intrinsic_id() == vmIntrinsics::_invoke) {
1501 // This is Method.invoke() -- ignore it
1502 return true;
1503 }
1504 if (method_holder()->is_subclass_of(vmClasses::reflect_MethodAccessorImpl_klass())) {
1505 // This is an auxiliary frame -- ignore it
1506 return true;
1507 }
1508 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1509 // This is an internal adapter frame for method handles -- ignore it
1510 return true;
1511 }
1512 return false;
1513 }
1514
1515
1516 // Constant pool structure for invoke methods:
1517 enum {
1518 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1519 _imcp_invoke_signature, // utf8: (variable Symbol*)
1520 _imcp_limit
1521 };
1522
1523 // Test if this method is an MH adapter frame generated by Java code.
1524 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1525 bool Method::is_compiled_lambda_form() const {
1526 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1527 }
1528
1529 // Test if this method is an internal MH primitive method.
1530 bool Method::is_method_handle_intrinsic() const {
1531 vmIntrinsics::ID iid = intrinsic_id();
1532 return (MethodHandles::is_signature_polymorphic(iid) &&
1533 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1534 }
1535
1536 bool Method::has_member_arg() const {
1537 vmIntrinsics::ID iid = intrinsic_id();
1538 return (MethodHandles::is_signature_polymorphic(iid) &&
1539 MethodHandles::has_member_arg(iid));
1540 }
1541
1542 // Make an instance of a signature-polymorphic internal MH primitive.
1543 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1544 Symbol* signature,
1545 TRAPS) {
1546 ResourceMark rm(THREAD);
1547 methodHandle empty;
1548
1549 InstanceKlass* holder = vmClasses::MethodHandle_klass();
1550 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1551 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1552
1553 log_info(methodhandles)("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1554
1555 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1556 name->increment_refcount();
1557 signature->increment_refcount();
1558
1559 int cp_length = _imcp_limit;
1560 ClassLoaderData* loader_data = holder->class_loader_data();
1561 constantPoolHandle cp;
1562 {
1563 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1564 cp = constantPoolHandle(THREAD, cp_oop);
1565 }
1566 cp->copy_fields(holder->constants());
1567 cp->set_pool_holder(holder);
1568 cp->symbol_at_put(_imcp_invoke_name, name);
1569 cp->symbol_at_put(_imcp_invoke_signature, signature);
1570 cp->set_has_preresolution();
1571 cp->set_is_for_method_handle_intrinsic();
1572
1573 // decide on access bits: public or not?
1574 u2 flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1575 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1576 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1577 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1578
1579 methodHandle m;
1580 {
1581 InlineTableSizes sizes;
1582 Method* m_oop = Method::allocate(loader_data, 0,
1583 accessFlags_from(flags_bits), &sizes,
1584 ConstMethod::NORMAL,
1585 name,
1586 CHECK_(empty));
1587 m = methodHandle(THREAD, m_oop);
1588 }
1589 m->set_constants(cp());
1590 m->set_name_index(_imcp_invoke_name);
1591 m->set_signature_index(_imcp_invoke_signature);
1592 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1593 assert(m->signature() == signature, "");
1594 m->constMethod()->compute_from_signature(signature, must_be_static);
1595 m->init_intrinsic_id(klass_id_for_intrinsics(m->method_holder()));
1596 assert(m->is_method_handle_intrinsic(), "");
1597 #ifdef ASSERT
1598 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1599 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1600 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1601 #endif //ASSERT
1602
1603 // Finally, set up its entry points.
1604 assert(m->can_be_statically_bound(), "");
1605 m->set_vtable_index(Method::nonvirtual_vtable_index);
1606 m->link_method(m, CHECK_(empty));
1607
1608 if (iid == vmIntrinsics::_linkToNative) {
1609 m->set_interpreter_entry(m->adapter()->get_i2c_entry());
1610 }
1611 if (log_is_enabled(Debug, methodhandles)) {
1612 LogTarget(Debug, methodhandles) lt;
1613 LogStream ls(lt);
1614 m->print_on(&ls);
1615 }
1616
1617 return m;
1618 }
1619
1620 #if INCLUDE_CDS
1621 void Method::restore_archived_method_handle_intrinsic(methodHandle m, TRAPS) {
1622 if (m->adapter() != nullptr) {
1623 m->set_from_compiled_entry(m->adapter()->get_c2i_entry());
1624 m->set_from_compiled_inline_entry(m->adapter()->get_c2i_inline_entry());
1625 m->set_from_compiled_inline_ro_entry(m->adapter()->get_c2i_inline_ro_entry());
1626 }
1627 m->link_method(m, CHECK);
1628
1629 if (m->intrinsic_id() == vmIntrinsics::_linkToNative) {
1630 m->set_interpreter_entry(m->adapter()->get_i2c_entry());
1631 }
1632 }
1633 #endif
1634
1635 Klass* Method::check_non_bcp_klass(Klass* klass) {
1636 if (klass != nullptr && klass->class_loader() != nullptr) {
1637 if (klass->is_objArray_klass())
1638 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1639 return klass;
1640 }
1641 return nullptr;
1642 }
1643
1644
1645 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1646 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1647 // Code below does not work for native methods - they should never get rewritten anyway
1648 assert(!m->is_native(), "cannot rewrite native methods");
1649 // Allocate new Method*
1650 AccessFlags flags = m->access_flags();
1651
1652 ConstMethod* cm = m->constMethod();
1653 int checked_exceptions_len = cm->checked_exceptions_length();
1654 int localvariable_len = cm->localvariable_table_length();
1655 int exception_table_len = cm->exception_table_length();
1656 int method_parameters_len = cm->method_parameters_length();
1657 int method_annotations_len = cm->method_annotations_length();
1658 int parameter_annotations_len = cm->parameter_annotations_length();
1659 int type_annotations_len = cm->type_annotations_length();
1660 int default_annotations_len = cm->default_annotations_length();
1661
1662 InlineTableSizes sizes(
1663 localvariable_len,
1664 new_compressed_linenumber_size,
1665 exception_table_len,
1666 checked_exceptions_len,
1667 method_parameters_len,
1668 cm->generic_signature_index(),
1669 method_annotations_len,
1670 parameter_annotations_len,
1671 type_annotations_len,
1672 default_annotations_len,
1673 0);
1674
1675 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1676 Method* newm_oop = Method::allocate(loader_data,
1677 new_code_length,
1678 flags,
1679 &sizes,
1680 m->method_type(),
1681 m->name(),
1682 CHECK_(methodHandle()));
1683 methodHandle newm (THREAD, newm_oop);
1684
1685 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1686 ConstMethod* newcm = newm->constMethod();
1687 int new_const_method_size = newm->constMethod()->size();
1688
1689 // This works because the source and target are both Methods. Some compilers
1690 // (e.g., clang) complain that the target vtable pointer will be stomped,
1691 // so cast away newm()'s and m()'s Methodness.
1692 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1693
1694 // Create shallow copy of ConstMethod.
1695 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1696
1697 // Reset correct method/const method, method size, and parameter info
1698 newm->set_constMethod(newcm);
1699 newm->constMethod()->set_code_size(new_code_length);
1700 newm->constMethod()->set_constMethod_size(new_const_method_size);
1701 assert(newm->code_size() == new_code_length, "check");
1702 assert(newm->method_parameters_length() == method_parameters_len, "check");
1703 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1704 assert(newm->exception_table_length() == exception_table_len, "check");
1705 assert(newm->localvariable_table_length() == localvariable_len, "check");
1706 // Copy new byte codes
1707 memcpy(newm->code_base(), new_code, new_code_length);
1708 // Copy line number table
1709 if (new_compressed_linenumber_size > 0) {
1710 memcpy(newm->compressed_linenumber_table(),
1711 new_compressed_linenumber_table,
1712 new_compressed_linenumber_size);
1713 }
1714 // Copy method_parameters
1715 if (method_parameters_len > 0) {
1716 memcpy(newm->method_parameters_start(),
1717 m->method_parameters_start(),
1718 method_parameters_len * sizeof(MethodParametersElement));
1719 }
1720 // Copy checked_exceptions
1721 if (checked_exceptions_len > 0) {
1722 memcpy(newm->checked_exceptions_start(),
1723 m->checked_exceptions_start(),
1724 checked_exceptions_len * sizeof(CheckedExceptionElement));
1725 }
1726 // Copy exception table
1727 if (exception_table_len > 0) {
1728 memcpy(newm->exception_table_start(),
1729 m->exception_table_start(),
1730 exception_table_len * sizeof(ExceptionTableElement));
1731 }
1732 // Copy local variable number table
1733 if (localvariable_len > 0) {
1734 memcpy(newm->localvariable_table_start(),
1735 m->localvariable_table_start(),
1736 localvariable_len * sizeof(LocalVariableTableElement));
1737 }
1738 // Copy stackmap table
1739 if (m->has_stackmap_table()) {
1740 int code_attribute_length = m->stackmap_data()->length();
1741 Array<u1>* stackmap_data =
1742 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_(methodHandle()));
1743 memcpy((void*)stackmap_data->adr_at(0),
1744 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1745 newm->set_stackmap_data(stackmap_data);
1746 }
1747
1748 // copy annotations over to new method
1749 newcm->copy_annotations_from(loader_data, cm, CHECK_(methodHandle()));
1750 return newm;
1751 }
1752
1753 vmSymbolID Method::klass_id_for_intrinsics(const Klass* holder) {
1754 // if loader is not the default loader (i.e., non-null), we can't know the intrinsics
1755 // because we are not loading from core libraries
1756 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1757 // which does not use the class default class loader so we check for its loader here
1758 const InstanceKlass* ik = InstanceKlass::cast(holder);
1759 if ((ik->class_loader() != nullptr) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1760 return vmSymbolID::NO_SID; // regardless of name, no intrinsics here
1761 }
1762
1763 // see if the klass name is well-known:
1764 Symbol* klass_name = ik->name();
1765 vmSymbolID id = vmSymbols::find_sid(klass_name);
1766 if (id != vmSymbolID::NO_SID && vmIntrinsics::class_has_intrinsics(id)) {
1767 return id;
1768 } else {
1769 return vmSymbolID::NO_SID;
1770 }
1771 }
1772
1773 void Method::init_intrinsic_id(vmSymbolID klass_id) {
1774 assert(_intrinsic_id == static_cast<int>(vmIntrinsics::_none), "do this just once");
1775 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1776 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1777 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1778
1779 // the klass name is well-known:
1780 assert(klass_id == klass_id_for_intrinsics(method_holder()), "must be");
1781 assert(klass_id != vmSymbolID::NO_SID, "caller responsibility");
1782
1783 // ditto for method and signature:
1784 vmSymbolID name_id = vmSymbols::find_sid(name());
1785 if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1786 && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1787 && name_id == vmSymbolID::NO_SID) {
1788 return;
1789 }
1790 vmSymbolID sig_id = vmSymbols::find_sid(signature());
1791 if (klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1792 && klass_id != VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1793 && sig_id == vmSymbolID::NO_SID) {
1794 return;
1795 }
1796
1797 u2 flags = access_flags().as_method_flags();
1798 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1799 if (id != vmIntrinsics::_none) {
1800 set_intrinsic_id(id);
1801 if (id == vmIntrinsics::_Class_cast) {
1802 // Even if the intrinsic is rejected, we want to inline this simple method.
1803 set_force_inline();
1804 }
1805 return;
1806 }
1807
1808 // A few slightly irregular cases:
1809 switch (klass_id) {
1810 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1811 case VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1812 case VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1813 if (!is_native()) break;
1814 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1815 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1816 id = vmIntrinsics::_none;
1817 break;
1818
1819 default:
1820 break;
1821 }
1822
1823 if (id != vmIntrinsics::_none) {
1824 // Set up its iid. It is an alias method.
1825 set_intrinsic_id(id);
1826 return;
1827 }
1828 }
1829
1830 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1831 if (!THREAD->can_call_java()) {
1832 // There is nothing useful this routine can do from within the Compile thread.
1833 // Hopefully, the signature contains only well-known classes.
1834 // We could scan for this and return true/false, but the caller won't care.
1835 return false;
1836 }
1837 bool sig_is_loaded = true;
1838 ResourceMark rm(THREAD);
1839 for (ResolvingSignatureStream ss(m()); !ss.is_done(); ss.next()) {
1840 if (ss.is_reference()) {
1841 // load everything, including arrays "[Lfoo;"
1842 Klass* klass = ss.as_klass(SignatureStream::ReturnNull, THREAD);
1843 // We are loading classes eagerly. If a ClassNotFoundException or
1844 // a LinkageError was generated, be sure to ignore it.
1845 if (HAS_PENDING_EXCEPTION) {
1846 if (PENDING_EXCEPTION->is_a(vmClasses::ClassNotFoundException_klass()) ||
1847 PENDING_EXCEPTION->is_a(vmClasses::LinkageError_klass())) {
1848 CLEAR_PENDING_EXCEPTION;
1849 } else {
1850 return false;
1851 }
1852 }
1853 if( klass == nullptr) { sig_is_loaded = false; }
1854 }
1855 }
1856 return sig_is_loaded;
1857 }
1858
1859 // Exposed so field engineers can debug VM
1860 void Method::print_short_name(outputStream* st) const {
1861 ResourceMark rm;
1862 #ifdef PRODUCT
1863 st->print(" %s::", method_holder()->external_name());
1864 #else
1865 st->print(" %s::", method_holder()->internal_name());
1866 #endif
1867 name()->print_symbol_on(st);
1868 if (WizardMode) signature()->print_symbol_on(st);
1869 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1870 MethodHandles::print_as_basic_type_signature_on(st, signature());
1871 }
1872
1873 // Comparer for sorting an object array containing
1874 // Method*s.
1875 static int method_comparator(Method* a, Method* b) {
1876 return a->name()->fast_compare(b->name());
1877 }
1878
1879 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1880 // default_methods also uses this without the ordering for fast find_method
1881 void Method::sort_methods(Array<Method*>* methods, bool set_idnums, method_comparator_func func) {
1882 int length = methods->length();
1883 if (length > 1) {
1884 if (func == nullptr) {
1885 func = method_comparator;
1886 }
1887 {
1888 NoSafepointVerifier nsv;
1889 QuickSort::sort(methods->data(), length, func);
1890 }
1891 // Reset method ordering
1892 if (set_idnums) {
1893 for (u2 i = 0; i < length; i++) {
1894 Method* m = methods->at(i);
1895 m->set_method_idnum(i);
1896 m->set_orig_method_idnum(i);
1897 }
1898 }
1899 }
1900 }
1901
1902 //-----------------------------------------------------------------------------------
1903 // Non-product code unless JVM/TI needs it
1904
1905 #if !defined(PRODUCT) || INCLUDE_JVMTI
1906 class SignatureTypePrinter : public SignatureTypeNames {
1907 private:
1908 outputStream* _st;
1909 bool _use_separator;
1910
1911 void type_name(const char* name) {
1912 if (_use_separator) _st->print(", ");
1913 _st->print("%s", name);
1914 _use_separator = true;
1915 }
1916
1917 public:
1918 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1919 _st = st;
1920 _use_separator = false;
1921 }
1922
1923 void print_parameters() { _use_separator = false; do_parameters_on(this); }
1924 void print_returntype() { _use_separator = false; do_type(return_type()); }
1925 };
1926
1927
1928 void Method::print_name(outputStream* st) const {
1929 Thread *thread = Thread::current();
1930 ResourceMark rm(thread);
1931 st->print("%s ", is_static() ? "static" : "virtual");
1932 if (WizardMode) {
1933 st->print("%s.", method_holder()->internal_name());
1934 name()->print_symbol_on(st);
1935 signature()->print_symbol_on(st);
1936 } else {
1937 SignatureTypePrinter sig(signature(), st);
1938 sig.print_returntype();
1939 st->print(" %s.", method_holder()->internal_name());
1940 name()->print_symbol_on(st);
1941 st->print("(");
1942 sig.print_parameters();
1943 st->print(")");
1944 }
1945 }
1946 #endif // !PRODUCT || INCLUDE_JVMTI
1947
1948
1949 void Method::print_codes_on(outputStream* st, int flags) const {
1950 print_codes_on(0, code_size(), st, flags);
1951 }
1952
1953 void Method::print_codes_on(int from, int to, outputStream* st, int flags) const {
1954 Thread *thread = Thread::current();
1955 ResourceMark rm(thread);
1956 methodHandle mh (thread, (Method*)this);
1957 BytecodeTracer::print_method_codes(mh, from, to, st, flags);
1958 }
1959
1960 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1961 _bci = 0;
1962 _line = 0;
1963 };
1964
1965 bool CompressedLineNumberReadStream::read_pair() {
1966 jubyte next = read_byte();
1967 // Check for terminator
1968 if (next == 0) return false;
1969 if (next == 0xFF) {
1970 // Escape character, regular compression used
1971 _bci += read_signed_int();
1972 _line += read_signed_int();
1973 } else {
1974 // Single byte compression used
1975 _bci += next >> 3;
1976 _line += next & 0x7;
1977 }
1978 return true;
1979 }
1980
1981 #if INCLUDE_JVMTI
1982
1983 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1984 BreakpointInfo* bp = method_holder()->breakpoints();
1985 for (; bp != nullptr; bp = bp->next()) {
1986 if (bp->match(this, bci)) {
1987 return bp->orig_bytecode();
1988 }
1989 }
1990 {
1991 ResourceMark rm;
1992 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1993 }
1994 return Bytecodes::_shouldnotreachhere;
1995 }
1996
1997 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1998 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1999 BreakpointInfo* bp = method_holder()->breakpoints();
2000 for (; bp != nullptr; bp = bp->next()) {
2001 if (bp->match(this, bci)) {
2002 bp->set_orig_bytecode(code);
2003 // and continue, in case there is more than one
2004 }
2005 }
2006 }
2007
2008 void Method::set_breakpoint(int bci) {
2009 InstanceKlass* ik = method_holder();
2010 BreakpointInfo *bp = new BreakpointInfo(this, bci);
2011 bp->set_next(ik->breakpoints());
2012 ik->set_breakpoints(bp);
2013 // do this last:
2014 bp->set(this);
2015 }
2016
2017 static void clear_matches(Method* m, int bci) {
2018 InstanceKlass* ik = m->method_holder();
2019 BreakpointInfo* prev_bp = nullptr;
2020 BreakpointInfo* next_bp;
2021 for (BreakpointInfo* bp = ik->breakpoints(); bp != nullptr; bp = next_bp) {
2022 next_bp = bp->next();
2023 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
2024 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
2025 // do this first:
2026 bp->clear(m);
2027 // unhook it
2028 if (prev_bp != nullptr)
2029 prev_bp->set_next(next_bp);
2030 else
2031 ik->set_breakpoints(next_bp);
2032 delete bp;
2033 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
2034 // at same location. So we have multiple matching (method_index and bci)
2035 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
2036 // breakpoint for clear_breakpoint request and keep all other method versions
2037 // BreakpointInfo for future clear_breakpoint request.
2038 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
2039 // which is being called when class is unloaded. We delete all the Breakpoint
2040 // information for all versions of method. We may not correctly restore the original
2041 // bytecode in all method versions, but that is ok. Because the class is being unloaded
2042 // so these methods won't be used anymore.
2043 if (bci >= 0) {
2044 break;
2045 }
2046 } else {
2047 // This one is a keeper.
2048 prev_bp = bp;
2049 }
2050 }
2051 }
2052
2053 void Method::clear_breakpoint(int bci) {
2054 assert(bci >= 0, "");
2055 clear_matches(this, bci);
2056 }
2057
2058 void Method::clear_all_breakpoints() {
2059 clear_matches(this, -1);
2060 }
2061
2062 #endif // INCLUDE_JVMTI
2063
2064 int Method::highest_osr_comp_level() const {
2065 const MethodCounters* mcs = method_counters();
2066 if (mcs != nullptr) {
2067 return mcs->highest_osr_comp_level();
2068 } else {
2069 return CompLevel_none;
2070 }
2071 }
2072
2073 void Method::set_highest_comp_level(int level) {
2074 MethodCounters* mcs = method_counters();
2075 if (mcs != nullptr) {
2076 mcs->set_highest_comp_level(level);
2077 }
2078 }
2079
2080 void Method::set_highest_osr_comp_level(int level) {
2081 MethodCounters* mcs = method_counters();
2082 if (mcs != nullptr) {
2083 mcs->set_highest_osr_comp_level(level);
2084 }
2085 }
2086
2087 #if INCLUDE_JVMTI
2088
2089 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
2090 _bci = bci;
2091 _name_index = m->name_index();
2092 _signature_index = m->signature_index();
2093 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
2094 if (_orig_bytecode == Bytecodes::_breakpoint)
2095 _orig_bytecode = m->orig_bytecode_at(_bci);
2096 _next = nullptr;
2097 }
2098
2099 void BreakpointInfo::set(Method* method) {
2100 #ifdef ASSERT
2101 {
2102 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
2103 if (code == Bytecodes::_breakpoint)
2104 code = method->orig_bytecode_at(_bci);
2105 assert(orig_bytecode() == code, "original bytecode must be the same");
2106 }
2107 #endif
2108 Thread *thread = Thread::current();
2109 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2110 method->incr_number_of_breakpoints(thread);
2111 {
2112 // Deoptimize all dependents on this method
2113 HandleMark hm(thread);
2114 methodHandle mh(thread, method);
2115 CodeCache::mark_dependents_on_method_for_breakpoint(mh);
2116 }
2117 }
2118
2119 void BreakpointInfo::clear(Method* method) {
2120 *method->bcp_from(_bci) = orig_bytecode();
2121 assert(method->number_of_breakpoints() > 0, "must not go negative");
2122 method->decr_number_of_breakpoints(Thread::current());
2123 }
2124
2125 #endif // INCLUDE_JVMTI
2126
2127 // jmethodID handling
2128 // jmethodIDs are 64-bit integers that will never run out and are mapped in a table
2129 // to their Method and vice versa. If JNI code has access to stale jmethodID, this
2130 // wastes no memory but the Method* returned is null.
2131
2132 // Add a method id to the jmethod_ids
2133 jmethodID Method::make_jmethod_id(ClassLoaderData* cld, Method* m) {
2134 // Have to add jmethod_ids() to class loader data thread-safely.
2135 // Also have to add the method to the InstanceKlass list safely, which the lock
2136 // protects as well.
2137 assert(JmethodIdCreation_lock->owned_by_self(), "sanity check");
2138 jmethodID jmid = JmethodIDTable::make_jmethod_id(m);
2139 assert(jmid != nullptr, "must be created");
2140
2141 // Add to growable array in CLD.
2142 cld->add_jmethod_id(jmid);
2143 return jmid;
2144 }
2145
2146 // This looks in the InstanceKlass cache, then calls back to make_jmethod_id if not found.
2147 jmethodID Method::jmethod_id() {
2148 return method_holder()->get_jmethod_id(this);
2149 }
2150
2151 // Get the Method out of the table given the method id.
2152 Method* Method::resolve_jmethod_id(jmethodID mid) {
2153 assert(mid != nullptr, "JNI method id should not be null");
2154 return JmethodIDTable::resolve_jmethod_id(mid);
2155 }
2156
2157 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2158 // Can't assert the method_holder is the same because the new method has the
2159 // scratch method holder.
2160 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2161 == new_method->method_holder()->class_loader() ||
2162 new_method->method_holder()->class_loader() == nullptr, // allow substitution to Unsafe method
2163 "changing to a different class loader");
2164 JmethodIDTable::change_method_associated_with_jmethod_id(jmid, new_method);
2165 }
2166
2167 // If there's a jmethodID for this method, clear the Method
2168 // but leave jmethodID for this method in the table.
2169 // It's deallocated with class unloading.
2170 void Method::clear_jmethod_id() {
2171 jmethodID mid = method_holder()->jmethod_id_or_null(this);
2172 if (mid != nullptr) {
2173 JmethodIDTable::clear_jmethod_id(mid, this);
2174 }
2175 }
2176
2177 bool Method::validate_jmethod_id(jmethodID mid) {
2178 Method* m = resolve_jmethod_id(mid);
2179 assert(m != nullptr, "should be called with non-null method");
2180 InstanceKlass* ik = m->method_holder();
2181 ClassLoaderData* cld = ik->class_loader_data();
2182 if (cld->jmethod_ids() == nullptr) return false;
2183 return (cld->jmethod_ids()->contains(mid));
2184 }
2185
2186 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2187 if (mid == nullptr) return nullptr;
2188 Method* o = resolve_jmethod_id(mid);
2189 if (o == nullptr) {
2190 return nullptr;
2191 }
2192 // Method should otherwise be valid. Assert for testing.
2193 assert(is_valid_method(o), "should be valid jmethodid");
2194 // If the method's class holder object is unreferenced, but not yet marked as
2195 // unloaded, we need to return null here too because after a safepoint, its memory
2196 // will be reclaimed.
2197 return o->method_holder()->is_loader_alive() ? o : nullptr;
2198 }
2199
2200 void Method::set_on_stack(const bool value) {
2201 // Set both the method itself and its constant pool. The constant pool
2202 // on stack means some method referring to it is also on the stack.
2203 constants()->set_on_stack(value);
2204
2205 bool already_set = on_stack_flag();
2206 set_on_stack_flag(value);
2207 if (value && !already_set) {
2208 MetadataOnStackMark::record(this);
2209 }
2210 }
2211
2212 void Method::record_gc_epoch() {
2213 // If any method is on the stack in continuations, none of them can be reclaimed,
2214 // so save the marking cycle to check for the whole class in the cpCache.
2215 // The cpCache is writeable.
2216 constants()->cache()->record_gc_epoch();
2217 }
2218
2219 bool Method::has_method_vptr(const void* ptr) {
2220 Method m;
2221 // This assumes that the vtbl pointer is the first word of a C++ object.
2222 return dereference_vptr(&m) == dereference_vptr(ptr);
2223 }
2224
2225 // Check that this pointer is valid by checking that the vtbl pointer matches
2226 bool Method::is_valid_method(const Method* m) {
2227 if (m == nullptr) {
2228 return false;
2229 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2230 // Quick sanity check on pointer.
2231 return false;
2232 } else if (!os::is_readable_range(m, m + 1)) {
2233 return false;
2234 } else if (m->is_shared()) {
2235 return CppVtables::is_valid_shared_method(m);
2236 } else if (Metaspace::contains_non_shared(m)) {
2237 return has_method_vptr((const void*)m);
2238 } else {
2239 return false;
2240 }
2241 }
2242
2243 bool Method::is_scalarized_arg(int idx) const {
2244 if (!has_scalarized_args()) {
2245 return false;
2246 }
2247 // Search through signature and check if argument is wrapped in T_METADATA/T_VOID
2248 int depth = 0;
2249 const GrowableArray<SigEntry>* sig = adapter()->get_sig_cc();
2250 for (int i = 0; i < sig->length(); i++) {
2251 BasicType bt = sig->at(i)._bt;
2252 if (bt == T_METADATA) {
2253 depth++;
2254 }
2255 if (idx == 0) {
2256 break; // Argument found
2257 }
2258 if (bt == T_VOID && (sig->at(i-1)._bt != T_LONG && sig->at(i-1)._bt != T_DOUBLE)) {
2259 depth--;
2260 }
2261 if (depth == 0 && bt != T_LONG && bt != T_DOUBLE) {
2262 idx--; // Advance to next argument
2263 }
2264 }
2265 return depth != 0;
2266 }
2267
2268 // Printing
2269
2270 #ifndef PRODUCT
2271
2272 void Method::print_on(outputStream* st) const {
2273 ResourceMark rm;
2274 assert(is_method(), "must be method");
2275 st->print_cr("%s", internal_name());
2276 st->print_cr(" - this oop: " PTR_FORMAT, p2i(this));
2277 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2278 st->print (" - constants: " PTR_FORMAT " ", p2i(constants()));
2279 constants()->print_value_on(st); st->cr();
2280 st->print (" - access: 0x%x ", access_flags().as_method_flags()); access_flags().print_on(st); st->cr();
2281 st->print (" - flags: 0x%x ", _flags.as_int()); _flags.print_on(st); st->cr();
2282 st->print (" - name: "); name()->print_value_on(st); st->cr();
2283 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2284 st->print_cr(" - max stack: %d", max_stack());
2285 st->print_cr(" - max locals: %d", max_locals());
2286 st->print_cr(" - size of params: %d", size_of_parameters());
2287 st->print_cr(" - method size: %d", method_size());
2288 if (intrinsic_id() != vmIntrinsics::_none)
2289 st->print_cr(" - intrinsic id: %d %s", vmIntrinsics::as_int(intrinsic_id()), vmIntrinsics::name_at(intrinsic_id()));
2290 if (highest_comp_level() != CompLevel_none)
2291 st->print_cr(" - highest level: %d", highest_comp_level());
2292 st->print_cr(" - vtable index: %d", _vtable_index);
2293 #ifdef ASSERT
2294 if (valid_itable_index())
2295 st->print_cr(" - itable index: %d", itable_index());
2296 #endif
2297 st->print_cr(" - i2i entry: " PTR_FORMAT, p2i(interpreter_entry()));
2298 st->print( " - adapters: ");
2299 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2300 if (a == nullptr)
2301 st->print_cr(PTR_FORMAT, p2i(a));
2302 else
2303 a->print_adapter_on(st);
2304 st->print_cr(" - compiled entry " PTR_FORMAT, p2i(from_compiled_entry()));
2305 st->print_cr(" - compiled inline entry " PTR_FORMAT, p2i(from_compiled_inline_entry()));
2306 st->print_cr(" - compiled inline ro entry " PTR_FORMAT, p2i(from_compiled_inline_ro_entry()));
2307 st->print_cr(" - code size: %d", code_size());
2308 if (code_size() != 0) {
2309 st->print_cr(" - code start: " PTR_FORMAT, p2i(code_base()));
2310 st->print_cr(" - code end (excl): " PTR_FORMAT, p2i(code_base() + code_size()));
2311 }
2312 if (method_data() != nullptr) {
2313 st->print_cr(" - method data: " PTR_FORMAT, p2i(method_data()));
2314 }
2315 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2316 if (checked_exceptions_length() > 0) {
2317 CheckedExceptionElement* table = checked_exceptions_start();
2318 st->print_cr(" - checked ex start: " PTR_FORMAT, p2i(table));
2319 if (Verbose) {
2320 for (int i = 0; i < checked_exceptions_length(); i++) {
2321 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2322 }
2323 }
2324 }
2325 if (has_linenumber_table()) {
2326 u_char* table = compressed_linenumber_table();
2327 st->print_cr(" - linenumber start: " PTR_FORMAT, p2i(table));
2328 if (Verbose) {
2329 CompressedLineNumberReadStream stream(table);
2330 while (stream.read_pair()) {
2331 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2332 }
2333 }
2334 }
2335 st->print_cr(" - localvar length: %d", localvariable_table_length());
2336 if (localvariable_table_length() > 0) {
2337 LocalVariableTableElement* table = localvariable_table_start();
2338 st->print_cr(" - localvar start: " PTR_FORMAT, p2i(table));
2339 if (Verbose) {
2340 for (int i = 0; i < localvariable_table_length(); i++) {
2341 int bci = table[i].start_bci;
2342 int len = table[i].length;
2343 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2344 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2345 int slot = table[i].slot;
2346 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2347 }
2348 }
2349 }
2350 if (code() != nullptr) {
2351 st->print (" - compiled code: ");
2352 code()->print_value_on(st);
2353 }
2354 if (is_native()) {
2355 st->print_cr(" - native function: " PTR_FORMAT, p2i(native_function()));
2356 st->print_cr(" - signature handler: " PTR_FORMAT, p2i(signature_handler()));
2357 }
2358 }
2359
2360 void Method::print_linkage_flags(outputStream* st) {
2361 access_flags().print_on(st);
2362 if (is_default_method()) {
2363 st->print("default ");
2364 }
2365 if (is_overpass()) {
2366 st->print("overpass ");
2367 }
2368 }
2369 #endif //PRODUCT
2370
2371 void Method::print_value_on(outputStream* st) const {
2372 assert(is_method(), "must be method");
2373 st->print("%s", internal_name());
2374 print_address_on(st);
2375 st->print(" ");
2376 if (WizardMode) access_flags().print_on(st);
2377 name()->print_value_on(st);
2378 st->print(" ");
2379 signature()->print_value_on(st);
2380 st->print(" in ");
2381 method_holder()->print_value_on(st);
2382 if (WizardMode) st->print("#%d", _vtable_index);
2383 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2384 if (WizardMode && code() != nullptr) st->print(" ((nmethod*)%p)", code());
2385 }
2386
2387 // Verification
2388
2389 void Method::verify_on(outputStream* st) {
2390 guarantee(is_method(), "object must be method");
2391 guarantee(constants()->is_constantPool(), "should be constant pool");
2392 MethodData* md = method_data();
2393 guarantee(md == nullptr ||
2394 md->is_methodData(), "should be method data");
2395 }