1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/classLoaderDataGraph.hpp"
27 #include "classfile/metadataOnStackMark.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "code/codeCache.hpp"
30 #include "code/debugInfoRec.hpp"
31 #include "gc/shared/collectedHeap.inline.hpp"
32 #include "interpreter/bytecodeStream.hpp"
33 #include "interpreter/bytecodeTracer.hpp"
34 #include "interpreter/bytecodes.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "interpreter/oopMapCache.hpp"
37 #include "memory/allocation.inline.hpp"
38 #include "memory/heapInspection.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/metaspaceClosure.hpp"
41 #include "memory/metaspaceShared.hpp"
42 #include "memory/oopFactory.hpp"
43 #include "memory/resourceArea.hpp"
44 #include "memory/universe.hpp"
45 #include "oops/constMethod.hpp"
46 #include "oops/constantPool.hpp"
47 #include "oops/method.inline.hpp"
48 #include "oops/methodData.hpp"
49 #include "oops/objArrayKlass.hpp"
50 #include "oops/objArrayOop.inline.hpp"
51 #include "oops/oop.inline.hpp"
52 #include "oops/symbol.hpp"
53 #include "oops/valueKlass.hpp"
54 #include "prims/jvmtiExport.hpp"
55 #include "prims/methodHandles.hpp"
56 #include "prims/nativeLookup.hpp"
57 #include "runtime/arguments.hpp"
58 #include "runtime/compilationPolicy.hpp"
59 #include "runtime/frame.inline.hpp"
60 #include "runtime/handles.inline.hpp"
61 #include "runtime/init.hpp"
62 #include "runtime/orderAccess.hpp"
63 #include "runtime/relocator.hpp"
64 #include "runtime/safepointVerifiers.hpp"
65 #include "runtime/sharedRuntime.hpp"
66 #include "runtime/signature.hpp"
67 #include "utilities/align.hpp"
68 #include "utilities/quickSort.hpp"
69 #include "utilities/vmError.hpp"
70 #include "utilities/xmlstream.hpp"
71
72 // Implementation of Method
73
74 Method* Method::allocate(ClassLoaderData* loader_data,
75 int byte_code_size,
76 AccessFlags access_flags,
77 InlineTableSizes* sizes,
78 ConstMethod::MethodType method_type,
79 TRAPS) {
80 assert(!access_flags.is_native() || byte_code_size == 0,
81 "native methods should not contain byte codes");
82 ConstMethod* cm = ConstMethod::allocate(loader_data,
83 byte_code_size,
84 sizes,
85 method_type,
86 CHECK_NULL);
87 int size = Method::size(access_flags.is_native());
88 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
89 }
90
91 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
92 NoSafepointVerifier no_safepoint;
93 set_constMethod(xconst);
94 set_access_flags(access_flags);
95 set_intrinsic_id(vmIntrinsics::_none);
96 set_force_inline(false);
97 set_hidden(false);
98 set_dont_inline(false);
99 set_has_injected_profile(false);
100 set_method_data(NULL);
101 clear_method_counters();
102 set_vtable_index(Method::garbage_vtable_index);
103
104 // Fix and bury in Method*
105 set_interpreter_entry(NULL); // sets i2i entry and from_int
106 set_adapter_entry(NULL);
107 Method::clear_code(); // from_c/from_i get set to c2i/i2i
108
109 if (access_flags.is_native()) {
110 clear_native_function();
111 set_signature_handler(NULL);
112 }
113 NOT_PRODUCT(set_compiled_invocation_count(0);)
114 }
115
116 // Release Method*. The nmethod will be gone when we get here because
117 // we've walked the code cache.
118 void Method::deallocate_contents(ClassLoaderData* loader_data) {
119 MetadataFactory::free_metadata(loader_data, constMethod());
120 set_constMethod(NULL);
121 #if INCLUDE_JVMCI
122 if (method_data()) {
123 FailedSpeculation::free_failed_speculations(method_data()->get_failed_speculations_address());
124 }
125 #endif
126 MetadataFactory::free_metadata(loader_data, method_data());
127 set_method_data(NULL);
128 MetadataFactory::free_metadata(loader_data, method_counters());
129 clear_method_counters();
130 // The nmethod will be gone when we get here.
131 if (code() != NULL) _code = NULL;
132 }
133
134 address Method::get_i2c_entry() {
135 assert(adapter() != NULL, "must have");
136 return adapter()->get_i2c_entry();
137 }
138
139 address Method::get_c2i_entry() {
140 assert(adapter() != NULL, "must have");
141 return adapter()->get_c2i_entry();
142 }
143
144 address Method::get_c2i_value_entry() {
145 assert(adapter() != NULL, "must have");
146 return adapter()->get_c2i_value_entry();
147 }
148
149 address Method::get_c2i_unverified_entry() {
150 assert(adapter() != NULL, "must have");
151 return adapter()->get_c2i_unverified_entry();
152 }
153
154 address Method::get_c2i_unverified_value_entry() {
155 assert(adapter() != NULL, "must have");
156 return adapter()->get_c2i_unverified_value_entry();
157 }
158
159 char* Method::name_and_sig_as_C_string() const {
160 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
161 }
162
163 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
164 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
165 }
166
167 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
168 const char* klass_name = klass->external_name();
169 int klass_name_len = (int)strlen(klass_name);
170 int method_name_len = method_name->utf8_length();
171 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
172 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
173 strcpy(dest, klass_name);
174 dest[klass_name_len] = '.';
175 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
176 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
177 dest[len] = 0;
178 return dest;
179 }
180
181 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
182 Symbol* klass_name = klass->name();
183 klass_name->as_klass_external_name(buf, size);
184 int len = (int)strlen(buf);
185
186 if (len < size - 1) {
187 buf[len++] = '.';
188
189 method_name->as_C_string(&(buf[len]), size - len);
190 len = (int)strlen(buf);
191
192 signature->as_C_string(&(buf[len]), size - len);
193 }
194
195 return buf;
196 }
197
198 const char* Method::external_name() const {
199 return external_name(constants()->pool_holder(), name(), signature());
200 }
201
202 void Method::print_external_name(outputStream *os) const {
203 print_external_name(os, constants()->pool_holder(), name(), signature());
204 }
205
206 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
207 stringStream ss;
208 print_external_name(&ss, klass, method_name, signature);
209 return ss.as_string();
210 }
211
212 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
213 signature->print_as_signature_external_return_type(os);
214 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
215 signature->print_as_signature_external_parameters(os);
216 os->print(")");
217 }
218
219 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
220 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
221 // access exception table
222 ExceptionTable table(mh());
223 int length = table.length();
224 // iterate through all entries sequentially
225 constantPoolHandle pool(THREAD, mh->constants());
226 for (int i = 0; i < length; i ++) {
227 //reacquire the table in case a GC happened
228 ExceptionTable table(mh());
229 int beg_bci = table.start_pc(i);
230 int end_bci = table.end_pc(i);
231 assert(beg_bci <= end_bci, "inconsistent exception table");
232 if (beg_bci <= throw_bci && throw_bci < end_bci) {
233 // exception handler bci range covers throw_bci => investigate further
234 int handler_bci = table.handler_pc(i);
235 int klass_index = table.catch_type_index(i);
236 if (klass_index == 0) {
237 return handler_bci;
238 } else if (ex_klass == NULL) {
239 return handler_bci;
240 } else {
241 // we know the exception class => get the constraint class
242 // this may require loading of the constraint class; if verification
243 // fails or some other exception occurs, return handler_bci
244 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
245 assert(k != NULL, "klass not loaded");
246 if (ex_klass->is_subtype_of(k)) {
247 return handler_bci;
248 }
249 }
250 }
251 }
252
253 return -1;
254 }
255
256 void Method::mask_for(int bci, InterpreterOopMap* mask) {
257 methodHandle h_this(Thread::current(), this);
258 // Only GC uses the OopMapCache during thread stack root scanning
259 // any other uses generate an oopmap but do not save it in the cache.
260 if (Universe::heap()->is_gc_active()) {
261 method_holder()->mask_for(h_this, bci, mask);
262 } else {
263 OopMapCache::compute_one_oop_map(h_this, bci, mask);
264 }
265 return;
266 }
267
268
269 int Method::bci_from(address bcp) const {
270 if (is_native() && bcp == 0) {
271 return 0;
272 }
273 #ifdef ASSERT
274 {
275 ResourceMark rm;
276 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
277 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
278 p2i(bcp), name_and_sig_as_C_string());
279 }
280 #endif
281 return bcp - code_base();
282 }
283
284
285 int Method::validate_bci(int bci) const {
286 return (bci == 0 || bci < code_size()) ? bci : -1;
287 }
288
289 // Return bci if it appears to be a valid bcp
290 // Return -1 otherwise.
291 // Used by profiling code, when invalid data is a possibility.
292 // The caller is responsible for validating the Method* itself.
293 int Method::validate_bci_from_bcp(address bcp) const {
294 // keep bci as -1 if not a valid bci
295 int bci = -1;
296 if (bcp == 0 || bcp == code_base()) {
297 // code_size() may return 0 and we allow 0 here
298 // the method may be native
299 bci = 0;
300 } else if (contains(bcp)) {
301 bci = bcp - code_base();
302 }
303 // Assert that if we have dodged any asserts, bci is negative.
304 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
305 return bci;
306 }
307
308 address Method::bcp_from(int bci) const {
309 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
310 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
311 address bcp = code_base() + bci;
312 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
313 return bcp;
314 }
315
316 address Method::bcp_from(address bcp) const {
317 if (is_native() && bcp == NULL) {
318 return code_base();
319 } else {
320 return bcp;
321 }
322 }
323
324 int Method::size(bool is_native) {
325 // If native, then include pointers for native_function and signature_handler
326 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
327 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
328 return align_metadata_size(header_size() + extra_words);
329 }
330
331
332 Symbol* Method::klass_name() const {
333 return method_holder()->name();
334 }
335
336
337 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
338 log_trace(cds)("Iter(Method): %p", this);
339
340 it->push(&_constMethod);
341 it->push(&_method_data);
342 it->push(&_method_counters);
343 }
344
345 // Attempt to return method oop to original state. Clear any pointers
346 // (to objects outside the shared spaces). We won't be able to predict
347 // where they should point in a new JVM. Further initialize some
348 // entries now in order allow them to be write protected later.
349
350 void Method::remove_unshareable_info() {
351 unlink_method();
352 }
353
354 void Method::set_vtable_index(int index) {
355 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
356 // At runtime initialize_vtable is rerun as part of link_class_impl()
357 // for a shared class loaded by the non-boot loader to obtain the loader
358 // constraints based on the runtime classloaders' context.
359 return; // don't write into the shared class
360 } else {
361 _vtable_index = index;
362 }
363 }
364
365 void Method::set_itable_index(int index) {
366 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
367 // At runtime initialize_itable is rerun as part of link_class_impl()
368 // for a shared class loaded by the non-boot loader to obtain the loader
369 // constraints based on the runtime classloaders' context. The dumptime
370 // itable index should be the same as the runtime index.
371 assert(_vtable_index == itable_index_max - index,
372 "archived itable index is different from runtime index");
373 return; // don’t write into the shared class
374 } else {
375 _vtable_index = itable_index_max - index;
376 }
377 assert(valid_itable_index(), "");
378 }
379
380
381
382 bool Method::was_executed_more_than(int n) {
383 // Invocation counter is reset when the Method* is compiled.
384 // If the method has compiled code we therefore assume it has
385 // be excuted more than n times.
386 if (is_accessor() || is_empty_method() || (code() != NULL)) {
387 // interpreter doesn't bump invocation counter of trivial methods
388 // compiler does not bump invocation counter of compiled methods
389 return true;
390 }
391 else if ((method_counters() != NULL &&
392 method_counters()->invocation_counter()->carry()) ||
393 (method_data() != NULL &&
394 method_data()->invocation_counter()->carry())) {
395 // The carry bit is set when the counter overflows and causes
396 // a compilation to occur. We don't know how many times
397 // the counter has been reset, so we simply assume it has
398 // been executed more than n times.
399 return true;
400 } else {
401 return invocation_count() > n;
402 }
403 }
404
405 void Method::print_invocation_count() {
406 if (is_static()) tty->print("static ");
407 if (is_final()) tty->print("final ");
408 if (is_synchronized()) tty->print("synchronized ");
409 if (is_native()) tty->print("native ");
410 tty->print("%s::", method_holder()->external_name());
411 name()->print_symbol_on(tty);
412 signature()->print_symbol_on(tty);
413
414 if (WizardMode) {
415 // dump the size of the byte codes
416 tty->print(" {%d}", code_size());
417 }
418 tty->cr();
419
420 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
421 tty->print_cr (" invocation_counter: %8d ", invocation_count());
422 tty->print_cr (" backedge_counter: %8d ", backedge_count());
423 #ifndef PRODUCT
424 if (CountCompiledCalls) {
425 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
426 }
427 #endif
428 }
429
430 // Build a MethodData* object to hold information about this method
431 // collected in the interpreter.
432 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
433 // Do not profile the method if metaspace has hit an OOM previously
434 // allocating profiling data. Callers clear pending exception so don't
435 // add one here.
436 if (ClassLoaderDataGraph::has_metaspace_oom()) {
437 return;
438 }
439
440 // Grab a lock here to prevent multiple
441 // MethodData*s from being created.
442 MutexLocker ml(MethodData_lock, THREAD);
443 if (method->method_data() == NULL) {
444 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
445 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
446 if (HAS_PENDING_EXCEPTION) {
447 CompileBroker::log_metaspace_failure();
448 ClassLoaderDataGraph::set_metaspace_oom(true);
449 return; // return the exception (which is cleared)
450 }
451
452 method->set_method_data(method_data);
453 if (PrintMethodData && (Verbose || WizardMode)) {
454 ResourceMark rm(THREAD);
455 tty->print("build_interpreter_method_data for ");
456 method->print_name(tty);
457 tty->cr();
458 // At the end of the run, the MDO, full of data, will be dumped.
459 }
460 }
461 }
462
463 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
464 // Do not profile the method if metaspace has hit an OOM previously
465 if (ClassLoaderDataGraph::has_metaspace_oom()) {
466 return NULL;
467 }
468
469 methodHandle mh(m);
470 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
471 if (HAS_PENDING_EXCEPTION) {
472 CompileBroker::log_metaspace_failure();
473 ClassLoaderDataGraph::set_metaspace_oom(true);
474 return NULL; // return the exception (which is cleared)
475 }
476 if (!mh->init_method_counters(counters)) {
477 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
478 }
479
480 if (LogTouchedMethods) {
481 mh->log_touched(CHECK_NULL);
482 }
483
484 return mh->method_counters();
485 }
486
487 bool Method::init_method_counters(MethodCounters* counters) {
488 // Try to install a pointer to MethodCounters, return true on success.
489 return Atomic::replace_if_null(counters, &_method_counters);
490 }
491
492 int Method::extra_stack_words() {
493 // not an inline function, to avoid a header dependency on Interpreter
494 return extra_stack_entries() * Interpreter::stackElementSize;
495 }
496
497
498 void Method::compute_size_of_parameters(Thread *thread) {
499 ArgumentSizeComputer asc(signature());
500 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
501 }
502
503 BasicType Method::result_type() const {
504 ResultTypeFinder rtf(signature());
505 return rtf.type();
506 }
507
508 #ifdef ASSERT
509 // ValueKlass the method is declared to return. This must not
510 // safepoint as it is called with references live on the stack at
511 // locations the GC is unaware of.
512 ValueKlass* Method::returned_value_type(Thread* thread) const {
513 SignatureStream ss(signature());
514 while (!ss.at_return_type()) {
515 ss.next();
516 }
517 Handle class_loader(thread, method_holder()->class_loader());
518 Handle protection_domain(thread, method_holder()->protection_domain());
519 Klass* k = NULL;
520 {
521 NoSafepointVerifier nsv;
522 k = ss.as_klass(class_loader, protection_domain, SignatureStream::ReturnNull, thread);
523 }
524 assert(k != NULL && !thread->has_pending_exception(), "can't resolve klass");
525 return ValueKlass::cast(k);
526 }
527 #endif
528
529 bool Method::is_empty_method() const {
530 return code_size() == 1
531 && *code_base() == Bytecodes::_return;
532 }
533
534
535 bool Method::is_vanilla_constructor() const {
536 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
537 // which only calls the superclass vanilla constructor and possibly does stores of
538 // zero constants to local fields:
539 //
540 // aload_0
541 // invokespecial
542 // indexbyte1
543 // indexbyte2
544 //
545 // followed by an (optional) sequence of:
546 //
547 // aload_0
548 // aconst_null / iconst_0 / fconst_0 / dconst_0
549 // putfield
550 // indexbyte1
551 // indexbyte2
552 //
553 // followed by:
554 //
555 // return
556
557 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
558 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
559 int size = code_size();
560 // Check if size match
561 if (size == 0 || size % 5 != 0) return false;
562 address cb = code_base();
563 int last = size - 1;
564 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
565 // Does not call superclass default constructor
566 return false;
567 }
568 // Check optional sequence
569 for (int i = 4; i < last; i += 5) {
570 if (cb[i] != Bytecodes::_aload_0) return false;
571 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
572 if (cb[i+2] != Bytecodes::_putfield) return false;
573 }
574 return true;
575 }
576
577
578 bool Method::compute_has_loops_flag() {
579 BytecodeStream bcs(this);
580 Bytecodes::Code bc;
581
582 while ((bc = bcs.next()) >= 0) {
583 switch( bc ) {
584 case Bytecodes::_ifeq:
585 case Bytecodes::_ifnull:
586 case Bytecodes::_iflt:
587 case Bytecodes::_ifle:
588 case Bytecodes::_ifne:
589 case Bytecodes::_ifnonnull:
590 case Bytecodes::_ifgt:
591 case Bytecodes::_ifge:
592 case Bytecodes::_if_icmpeq:
593 case Bytecodes::_if_icmpne:
594 case Bytecodes::_if_icmplt:
595 case Bytecodes::_if_icmpgt:
596 case Bytecodes::_if_icmple:
597 case Bytecodes::_if_icmpge:
598 case Bytecodes::_if_acmpeq:
599 case Bytecodes::_if_acmpne:
600 case Bytecodes::_goto:
601 case Bytecodes::_jsr:
602 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
603 break;
604
605 case Bytecodes::_goto_w:
606 case Bytecodes::_jsr_w:
607 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
608 break;
609
610 default:
611 break;
612 }
613 }
614 _access_flags.set_loops_flag_init();
615 return _access_flags.has_loops();
616 }
617
618 bool Method::is_final_method(AccessFlags class_access_flags) const {
619 // or "does_not_require_vtable_entry"
620 // default method or overpass can occur, is not final (reuses vtable entry)
621 // private methods in classes get vtable entries for backward class compatibility.
622 if (is_overpass() || is_default_method()) return false;
623 return is_final() || class_access_flags.is_final();
624 }
625
626 bool Method::is_final_method() const {
627 return is_final_method(method_holder()->access_flags());
628 }
629
630 bool Method::is_default_method() const {
631 if (method_holder() != NULL &&
632 method_holder()->is_interface() &&
633 !is_abstract() && !is_private()) {
634 return true;
635 } else {
636 return false;
637 }
638 }
639
640 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
641 if (is_final_method(class_access_flags)) return true;
642 #ifdef ASSERT
643 ResourceMark rm;
644 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
645 if (class_access_flags.is_interface()) {
646 assert(is_nonv == is_static() || is_nonv == is_private(),
647 "nonvirtual unexpected for non-static, non-private: %s",
648 name_and_sig_as_C_string());
649 }
650 #endif
651 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
652 return vtable_index() == nonvirtual_vtable_index;
653 }
654
655 bool Method::can_be_statically_bound() const {
656 return can_be_statically_bound(method_holder()->access_flags());
657 }
658
659 bool Method::can_be_statically_bound(InstanceKlass* context) const {
660 return (method_holder() == context) && can_be_statically_bound();
661 }
662
663 bool Method::is_accessor() const {
664 return is_getter() || is_setter();
665 }
666
667 bool Method::is_getter() const {
668 if (code_size() != 5) return false;
669 if (size_of_parameters() != 1) return false;
670 if (java_code_at(0) != Bytecodes::_aload_0) return false;
671 if (java_code_at(1) != Bytecodes::_getfield) return false;
672 switch (java_code_at(4)) {
673 case Bytecodes::_ireturn:
674 case Bytecodes::_lreturn:
675 case Bytecodes::_freturn:
676 case Bytecodes::_dreturn:
677 case Bytecodes::_areturn:
678 break;
679 default:
680 return false;
681 }
682 return true;
683 }
684
685 bool Method::is_setter() const {
686 if (code_size() != 6) return false;
687 if (java_code_at(0) != Bytecodes::_aload_0) return false;
688 switch (java_code_at(1)) {
689 case Bytecodes::_iload_1:
690 case Bytecodes::_aload_1:
691 case Bytecodes::_fload_1:
692 if (size_of_parameters() != 2) return false;
693 break;
694 case Bytecodes::_dload_1:
695 case Bytecodes::_lload_1:
696 if (size_of_parameters() != 3) return false;
697 break;
698 default:
699 return false;
700 }
701 if (java_code_at(2) != Bytecodes::_putfield) return false;
702 if (java_code_at(5) != Bytecodes::_return) return false;
703 return true;
704 }
705
706 bool Method::is_constant_getter() const {
707 int last_index = code_size() - 1;
708 // Check if the first 1-3 bytecodes are a constant push
709 // and the last bytecode is a return.
710 return (2 <= code_size() && code_size() <= 4 &&
711 Bytecodes::is_const(java_code_at(0)) &&
712 Bytecodes::length_for(java_code_at(0)) == last_index &&
713 Bytecodes::is_return(java_code_at(last_index)));
714 }
715
716 bool Method::is_object_constructor_or_class_initializer() const {
717 return (is_object_constructor() || is_class_initializer());
718 }
719
720 bool Method::is_class_initializer() const {
721 // For classfiles version 51 or greater, ensure that the clinit method is
722 // static. Non-static methods with the name "<clinit>" are not static
723 // initializers. (older classfiles exempted for backward compatibility)
724 return (name() == vmSymbols::class_initializer_name() &&
725 (is_static() ||
726 method_holder()->major_version() < 51));
727 }
728
729 // A method named <init>, if non-static, is a classic object constructor.
730 bool Method::is_object_constructor() const {
731 return name() == vmSymbols::object_initializer_name() && !is_static();
732 }
733
734 // A static method named <init> is a factory for an inline class.
735 bool Method::is_static_init_factory() const {
736 return name() == vmSymbols::object_initializer_name() && is_static();
737 }
738
739 bool Method::needs_clinit_barrier() const {
740 return is_static() && !method_holder()->is_initialized();
741 }
742
743 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
744 int length = method->checked_exceptions_length();
745 if (length == 0) { // common case
746 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
747 } else {
748 methodHandle h_this(THREAD, method);
749 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
750 objArrayHandle mirrors (THREAD, m_oop);
751 for (int i = 0; i < length; i++) {
752 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
753 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
754 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
755 mirrors->obj_at_put(i, k->java_mirror());
756 }
757 return mirrors;
758 }
759 };
760
761
762 int Method::line_number_from_bci(int bci) const {
763 int best_bci = 0;
764 int best_line = -1;
765 if (bci == SynchronizationEntryBCI) bci = 0;
766 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
767 // The line numbers are a short array of 2-tuples [start_pc, line_number].
768 // Not necessarily sorted and not necessarily one-to-one.
769 CompressedLineNumberReadStream stream(compressed_linenumber_table());
770 while (stream.read_pair()) {
771 if (stream.bci() == bci) {
772 // perfect match
773 return stream.line();
774 } else {
775 // update best_bci/line
776 if (stream.bci() < bci && stream.bci() >= best_bci) {
777 best_bci = stream.bci();
778 best_line = stream.line();
779 }
780 }
781 }
782 }
783 return best_line;
784 }
785
786
787 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
788 if( constants()->tag_at(klass_index).is_unresolved_klass()) {
789 Thread *thread = Thread::current();
790 Symbol* klass_name = constants()->klass_name_at(klass_index);
791 Handle loader(thread, method_holder()->class_loader());
792 Handle prot (thread, method_holder()->protection_domain());
793 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
794 } else {
795 return true;
796 }
797 }
798
799
800 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
801 int klass_index = constants()->klass_ref_index_at(refinfo_index);
802 if (must_be_resolved) {
803 // Make sure klass is resolved in constantpool.
804 if (constants()->tag_at(klass_index).is_unresolved_klass()) {
805 return false;
806 }
807 }
808 return is_klass_loaded_by_klass_index(klass_index);
809 }
810
811
812 void Method::set_native_function(address function, bool post_event_flag) {
813 assert(function != NULL, "use clear_native_function to unregister natives");
814 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
815 address* native_function = native_function_addr();
816
817 // We can see racers trying to place the same native function into place. Once
818 // is plenty.
819 address current = *native_function;
820 if (current == function) return;
821 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
822 function != NULL) {
823 // native_method_throw_unsatisfied_link_error_entry() should only
824 // be passed when post_event_flag is false.
825 assert(function !=
826 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
827 "post_event_flag mis-match");
828
829 // post the bind event, and possible change the bind function
830 JvmtiExport::post_native_method_bind(this, &function);
831 }
832 *native_function = function;
833 // This function can be called more than once. We must make sure that we always
834 // use the latest registered method -> check if a stub already has been generated.
835 // If so, we have to make it not_entrant.
836 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
837 if (nm != NULL) {
838 nm->make_not_entrant();
839 }
840 }
841
842
843 bool Method::has_native_function() const {
844 if (is_method_handle_intrinsic())
845 return false; // special-cased in SharedRuntime::generate_native_wrapper
846 address func = native_function();
847 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
848 }
849
850
851 void Method::clear_native_function() {
852 // Note: is_method_handle_intrinsic() is allowed here.
853 set_native_function(
854 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
855 !native_bind_event_is_interesting);
856 this->unlink_code();
857 }
858
859 address Method::critical_native_function() {
860 methodHandle mh(this);
861 return NativeLookup::lookup_critical_entry(mh);
862 }
863
864
865 void Method::set_signature_handler(address handler) {
866 address* signature_handler = signature_handler_addr();
867 *signature_handler = handler;
868 }
869
870
871 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
872 assert(reason != NULL, "must provide a reason");
873 if (PrintCompilation && report) {
874 ttyLocker ttyl;
875 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
876 if (comp_level == CompLevel_all) {
877 tty->print("all levels ");
878 } else {
879 tty->print("levels ");
880 for (int i = (int)CompLevel_none; i <= comp_level; i++) {
881 tty->print("%d ", i);
882 }
883 }
884 this->print_short_name(tty);
885 int size = this->code_size();
886 if (size > 0) {
887 tty->print(" (%d bytes)", size);
888 }
889 if (reason != NULL) {
890 tty->print(" %s", reason);
891 }
892 tty->cr();
893 }
894 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
895 ttyLocker ttyl;
896 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
897 os::current_thread_id(), is_osr, comp_level);
898 if (reason != NULL) {
899 xtty->print(" reason=\'%s\'", reason);
900 }
901 xtty->method(this);
902 xtty->stamp();
903 xtty->end_elem();
904 }
905 }
906
907 bool Method::is_always_compilable() const {
908 // Generated adapters must be compiled
909 if (is_method_handle_intrinsic() && is_synthetic()) {
910 assert(!is_not_c1_compilable(), "sanity check");
911 assert(!is_not_c2_compilable(), "sanity check");
912 return true;
913 }
914
915 return false;
916 }
917
918 bool Method::is_not_compilable(int comp_level) const {
919 if (number_of_breakpoints() > 0)
920 return true;
921 if (is_always_compilable())
922 return false;
923 if (comp_level == CompLevel_any)
924 return is_not_c1_compilable() || is_not_c2_compilable();
925 if (is_c1_compile(comp_level))
926 return is_not_c1_compilable();
927 if (is_c2_compile(comp_level))
928 return is_not_c2_compilable();
929 return false;
930 }
931
932 // call this when compiler finds that this method is not compilable
933 void Method::set_not_compilable(const char* reason, int comp_level, bool report) {
934 if (is_always_compilable()) {
935 // Don't mark a method which should be always compilable
936 return;
937 }
938 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
939 if (comp_level == CompLevel_all) {
940 set_not_c1_compilable();
941 set_not_c2_compilable();
942 } else {
943 if (is_c1_compile(comp_level))
944 set_not_c1_compilable();
945 if (is_c2_compile(comp_level))
946 set_not_c2_compilable();
947 }
948 CompilationPolicy::policy()->disable_compilation(this);
949 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
950 }
951
952 bool Method::is_not_osr_compilable(int comp_level) const {
953 if (is_not_compilable(comp_level))
954 return true;
955 if (comp_level == CompLevel_any)
956 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
957 if (is_c1_compile(comp_level))
958 return is_not_c1_osr_compilable();
959 if (is_c2_compile(comp_level))
960 return is_not_c2_osr_compilable();
961 return false;
962 }
963
964 void Method::set_not_osr_compilable(const char* reason, int comp_level, bool report) {
965 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
966 if (comp_level == CompLevel_all) {
967 set_not_c1_osr_compilable();
968 set_not_c2_osr_compilable();
969 } else {
970 if (is_c1_compile(comp_level))
971 set_not_c1_osr_compilable();
972 if (is_c2_compile(comp_level))
973 set_not_c2_osr_compilable();
974 }
975 CompilationPolicy::policy()->disable_compilation(this);
976 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
977 }
978
979 // Revert to using the interpreter and clear out the nmethod
980 void Method::clear_code() {
981 // this may be NULL if c2i adapters have not been made yet
982 // Only should happen at allocate time.
983 if (adapter() == NULL) {
984 _from_compiled_entry = NULL;
985 _from_compiled_value_entry = NULL;
986 _from_compiled_value_ro_entry = NULL;
987 } else {
988 _from_compiled_entry = adapter()->get_c2i_entry();
989 _from_compiled_value_entry = adapter()->get_c2i_value_entry();
990 _from_compiled_value_ro_entry = adapter()->get_c2i_value_ro_entry();
991 }
992 OrderAccess::storestore();
993 _from_interpreted_entry = _i2i_entry;
994 OrderAccess::storestore();
995 _code = NULL;
996 }
997
998 void Method::unlink_code(CompiledMethod *compare) {
999 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1000 // We need to check if either the _code or _from_compiled_code_entry_point
1001 // refer to this nmethod because there is a race in setting these two fields
1002 // in Method* as seen in bugid 4947125.
1003 // If the vep() points to the zombie nmethod, the memory for the nmethod
1004 // could be flushed and the compiler and vtable stubs could still call
1005 // through it.
1006 if (code() == compare ||
1007 from_compiled_entry() == compare->verified_entry_point()) {
1008 clear_code();
1009 }
1010 }
1011
1012 void Method::unlink_code() {
1013 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1014 clear_code();
1015 }
1016
1017 #if INCLUDE_CDS
1018 // Called by class data sharing to remove any entry points (which are not shared)
1019 void Method::unlink_method() {
1020 _code = NULL;
1021
1022 assert(DumpSharedSpaces || DynamicDumpSharedSpaces, "dump time only");
1023 // Set the values to what they should be at run time. Note that
1024 // this Method can no longer be executed during dump time.
1025 _i2i_entry = Interpreter::entry_for_cds_method(this);
1026 _from_interpreted_entry = _i2i_entry;
1027
1028 if (DynamicDumpSharedSpaces) {
1029 assert(_from_compiled_entry != NULL, "sanity");
1030 } else {
1031 // TODO: Simplify the adapter trampoline allocation for static archiving.
1032 // Remove the use of CDSAdapterHandlerEntry.
1033 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
1034 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
1035 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
1036 assert(*((int*)_from_compiled_entry) == 0,
1037 "must be NULL during dump time, to be initialized at run time");
1038 _from_compiled_value_ro_entry = cds_adapter->get_c2i_entry_trampoline(); // FIXME - doesn't work if you have value args!
1039 assert(*((int*)_from_compiled_value_ro_entry) == 0,
1040 "must be NULL during dump time, to be initialized at run time");
1041 _from_compiled_value_entry = cds_adapter->get_c2i_entry_trampoline(); // FIXME - doesn't work if you have value args (or this is value type)!
1042 assert(*((int*)_from_compiled_value_entry) == 0,
1043 "must be NULL during dump time, to be initialized at run time");
1044 assert(!method_holder()->is_value(), "FIXME: valuetype not supported by CDS");
1045 }
1046
1047 if (is_native()) {
1048 *native_function_addr() = NULL;
1049 set_signature_handler(NULL);
1050 }
1051 NOT_PRODUCT(set_compiled_invocation_count(0);)
1052
1053 set_method_data(NULL);
1054 clear_method_counters();
1055 }
1056 #endif
1057
1058 /****************************************************************************
1059 // The following illustrates how the entries work for CDS shared Methods:
1060 //
1061 // Our goal is to delay writing into a shared Method until it's compiled.
1062 // Hence, we want to determine the initial values for _i2i_entry,
1063 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
1064 //
1065 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
1066 // They also have similar signatures so that they will share the same
1067 // AdapterHandlerEntry.
1068 //
1069 // _adapter_trampoline points to a fixed location in the RW section of
1070 // the CDS archive. This location initially contains a NULL pointer. When the
1071 // first of method A or B is linked, an AdapterHandlerEntry is allocated
1072 // dynamically, and its c2i/i2c entries are generated.
1073 //
1074 // _i2i_entry and _from_interpreted_entry initially points to the same
1075 // (fixed) location in the CODE section of the CDS archive. This contains
1076 // an unconditional branch to the actual entry for "zero_locals", which is
1077 // generated at run time and may be on an arbitrary address. Thus, the
1078 // unconditional branch is also generated at run time to jump to the correct
1079 // address.
1080 //
1081 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1082 // section. This address has enough space for an unconditional branch
1083 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1084 // initialized, and the address for the actual c2i_entry is known, we emit a
1085 // branch instruction here to branch to the actual c2i_entry.
1086 //
1087 // The effect of the extra branch on the i2i and c2i entries is negligible.
1088 //
1089 // The reason for putting _adapter_trampoline in RO is many shared Methods
1090 // share the same AdapterHandlerEntry, so we can save space in the RW section
1091 // by having the extra indirection.
1092
1093
1094 [Method A: RW]
1095 _constMethod ----> [ConstMethod: RO]
1096 _adapter_trampoline -----------+
1097 |
1098 _i2i_entry (same value as method B) |
1099 _from_interpreted_entry (same value as method B) |
1100 _from_compiled_entry (same value as method B) |
1101 |
1102 |
1103 [Method B: RW] +--------+
1104 _constMethod ----> [ConstMethod: RO] |
1105 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1106 |
1107 +-------------------------------+
1108 |
1109 +----> [AdapterHandlerEntry] (allocated at run time)
1110 _fingerprint
1111 _c2i_entry ---------------------------------+->[c2i entry..]
1112 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1113 _from_interpreted_entry | _c2i_unverified_entry | |
1114 | | | |
1115 | | (_cds_entry_table: CODE) | |
1116 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1117 | | (allocated at run time) | |
1118 | | ... [asm code ...] | |
1119 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1120 | | |
1121 | | |
1122 +-[compiled]-------------------------------------------------------------------+ |
1123 |
1124 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1125 [jmp c2i_entry] ------------------------------------------------------+
1126
1127 ***/
1128
1129 // Called when the method_holder is getting linked. Setup entrypoints so the method
1130 // is ready to be called from interpreter, compiler, and vtables.
1131 void Method::link_method(const methodHandle& h_method, TRAPS) {
1132 // If the code cache is full, we may reenter this function for the
1133 // leftover methods that weren't linked.
1134 if (is_shared()) {
1135 address entry = Interpreter::entry_for_cds_method(h_method);
1136 assert(entry != NULL && entry == _i2i_entry,
1137 "should be correctly set during dump time");
1138 if (adapter() != NULL) {
1139 return;
1140 }
1141 assert(entry == _from_interpreted_entry,
1142 "should be correctly set during dump time");
1143 } else if (_i2i_entry != NULL) {
1144 return;
1145 }
1146 assert( _code == NULL, "nothing compiled yet" );
1147
1148 // Setup interpreter entrypoint
1149 assert(this == h_method(), "wrong h_method()" );
1150
1151 if (!is_shared()) {
1152 assert(adapter() == NULL, "init'd to NULL");
1153 address entry = Interpreter::entry_for_method(h_method);
1154 assert(entry != NULL, "interpreter entry must be non-null");
1155 // Sets both _i2i_entry and _from_interpreted_entry
1156 set_interpreter_entry(entry);
1157 }
1158
1159 // Don't overwrite already registered native entries.
1160 if (is_native() && !has_native_function()) {
1161 set_native_function(
1162 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1163 !native_bind_event_is_interesting);
1164 }
1165
1166 // Setup compiler entrypoint. This is made eagerly, so we do not need
1167 // special handling of vtables. An alternative is to make adapters more
1168 // lazily by calling make_adapter() from from_compiled_entry() for the
1169 // normal calls. For vtable calls life gets more complicated. When a
1170 // call-site goes mega-morphic we need adapters in all methods which can be
1171 // called from the vtable. We need adapters on such methods that get loaded
1172 // later. Ditto for mega-morphic itable calls. If this proves to be a
1173 // problem we'll make these lazily later.
1174 (void) make_adapters(h_method, CHECK);
1175
1176 // ONLY USE the h_method now as make_adapter may have blocked
1177
1178 }
1179
1180 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1181 // Adapters for compiled code are made eagerly here. They are fairly
1182 // small (generally < 100 bytes) and quick to make (and cached and shared)
1183 // so making them eagerly shouldn't be too expensive.
1184 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1185 if (adapter == NULL ) {
1186 if (!is_init_completed()) {
1187 // Don't throw exceptions during VM initialization because java.lang.* classes
1188 // might not have been initialized, causing problems when constructing the
1189 // Java exception object.
1190 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1191 } else {
1192 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1193 }
1194 }
1195
1196 if (mh->is_shared()) {
1197 assert(mh->adapter() == adapter, "must be");
1198 assert(mh->_from_compiled_entry != NULL, "must be");
1199 assert(mh->_from_compiled_value_entry != NULL, "must be");
1200 assert(mh->_from_compiled_value_ro_entry != NULL, "must be");
1201 } else {
1202 mh->set_adapter_entry(adapter);
1203 mh->_from_compiled_entry = adapter->get_c2i_entry();
1204 mh->_from_compiled_value_entry = adapter->get_c2i_value_entry();
1205 mh->_from_compiled_value_ro_entry = adapter->get_c2i_value_ro_entry();
1206 }
1207 return adapter->get_c2i_entry();
1208 }
1209
1210 void Method::restore_unshareable_info(TRAPS) {
1211 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1212
1213 // Since restore_unshareable_info can be called more than once for a method, don't
1214 // redo any work.
1215 if (adapter() == NULL) {
1216 methodHandle mh(THREAD, this);
1217 link_method(mh, CHECK);
1218 }
1219 }
1220
1221 address Method::from_compiled_entry_no_trampoline() const {
1222 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1223 if (code) {
1224 return code->verified_entry_point();
1225 } else {
1226 return adapter()->get_c2i_entry();
1227 }
1228 }
1229
1230 // The verified_code_entry() must be called when a invoke is resolved
1231 // on this method.
1232
1233 // It returns the compiled code entry point, after asserting not null.
1234 // This function is called after potential safepoints so that nmethod
1235 // or adapter that it points to is still live and valid.
1236 // This function must not hit a safepoint!
1237 address Method::verified_code_entry() {
1238 debug_only(NoSafepointVerifier nsv;)
1239 assert(_from_compiled_entry != NULL, "must be set");
1240 return _from_compiled_entry;
1241 }
1242
1243 address Method::verified_value_code_entry() {
1244 debug_only(NoSafepointVerifier nsv;)
1245 assert(_from_compiled_value_entry != NULL, "must be set");
1246 return _from_compiled_value_entry;
1247 }
1248
1249 address Method::verified_value_ro_code_entry() {
1250 debug_only(NoSafepointVerifier nsv;)
1251 assert(_from_compiled_value_ro_entry != NULL, "must be set");
1252 return _from_compiled_value_ro_entry;
1253 }
1254
1255 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1256 // (could be racing a deopt).
1257 // Not inline to avoid circular ref.
1258 bool Method::check_code() const {
1259 // cached in a register or local. There's a race on the value of the field.
1260 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1261 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1262 }
1263
1264 // Install compiled code. Instantly it can execute.
1265 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1266 MutexLocker pl(CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1267 assert( code, "use clear_code to remove code" );
1268 assert( mh->check_code(), "" );
1269
1270 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1271
1272 // These writes must happen in this order, because the interpreter will
1273 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1274 // which jumps to _from_compiled_entry.
1275 mh->_code = code; // Assign before allowing compiled code to exec
1276
1277 int comp_level = code->comp_level();
1278 // In theory there could be a race here. In practice it is unlikely
1279 // and not worth worrying about.
1280 if (comp_level > mh->highest_comp_level()) {
1281 mh->set_highest_comp_level(comp_level);
1282 }
1283
1284 OrderAccess::storestore();
1285 mh->_from_compiled_entry = code->verified_entry_point();
1286 mh->_from_compiled_value_entry = code->verified_value_entry_point();
1287 mh->_from_compiled_value_ro_entry = code->verified_value_ro_entry_point();
1288 OrderAccess::storestore();
1289 // Instantly compiled code can execute.
1290 if (!mh->is_method_handle_intrinsic())
1291 mh->_from_interpreted_entry = mh->get_i2c_entry();
1292 }
1293
1294
1295 bool Method::is_overridden_in(Klass* k) const {
1296 InstanceKlass* ik = InstanceKlass::cast(k);
1297
1298 if (ik->is_interface()) return false;
1299
1300 // If method is an interface, we skip it - except if it
1301 // is a miranda method
1302 if (method_holder()->is_interface()) {
1303 // Check that method is not a miranda method
1304 if (ik->lookup_method(name(), signature()) == NULL) {
1305 // No implementation exist - so miranda method
1306 return false;
1307 }
1308 return true;
1309 }
1310
1311 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1312 if (!has_vtable_index()) {
1313 return false;
1314 } else {
1315 Method* vt_m = ik->method_at_vtable(vtable_index());
1316 return vt_m != this;
1317 }
1318 }
1319
1320
1321 // give advice about whether this Method* should be cached or not
1322 bool Method::should_not_be_cached() const {
1323 if (is_old()) {
1324 // This method has been redefined. It is either EMCP or obsolete
1325 // and we don't want to cache it because that would pin the method
1326 // down and prevent it from being collectible if and when it
1327 // finishes executing.
1328 return true;
1329 }
1330
1331 // caching this method should be just fine
1332 return false;
1333 }
1334
1335
1336 /**
1337 * Returns true if this is one of the specially treated methods for
1338 * security related stack walks (like Reflection.getCallerClass).
1339 */
1340 bool Method::is_ignored_by_security_stack_walk() const {
1341 if (intrinsic_id() == vmIntrinsics::_invoke) {
1342 // This is Method.invoke() -- ignore it
1343 return true;
1344 }
1345 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1346 // This is an auxilary frame -- ignore it
1347 return true;
1348 }
1349 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1350 // This is an internal adapter frame for method handles -- ignore it
1351 return true;
1352 }
1353 return false;
1354 }
1355
1356
1357 // Constant pool structure for invoke methods:
1358 enum {
1359 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1360 _imcp_invoke_signature, // utf8: (variable Symbol*)
1361 _imcp_limit
1362 };
1363
1364 // Test if this method is an MH adapter frame generated by Java code.
1365 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1366 bool Method::is_compiled_lambda_form() const {
1367 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1368 }
1369
1370 // Test if this method is an internal MH primitive method.
1371 bool Method::is_method_handle_intrinsic() const {
1372 vmIntrinsics::ID iid = intrinsic_id();
1373 return (MethodHandles::is_signature_polymorphic(iid) &&
1374 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1375 }
1376
1377 bool Method::has_member_arg() const {
1378 vmIntrinsics::ID iid = intrinsic_id();
1379 return (MethodHandles::is_signature_polymorphic(iid) &&
1380 MethodHandles::has_member_arg(iid));
1381 }
1382
1383 // Make an instance of a signature-polymorphic internal MH primitive.
1384 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1385 Symbol* signature,
1386 TRAPS) {
1387 ResourceMark rm;
1388 methodHandle empty;
1389
1390 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1391 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1392 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1393 if (TraceMethodHandles) {
1394 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1395 }
1396
1397 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1398 name->increment_refcount();
1399 signature->increment_refcount();
1400
1401 int cp_length = _imcp_limit;
1402 ClassLoaderData* loader_data = holder->class_loader_data();
1403 constantPoolHandle cp;
1404 {
1405 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1406 cp = constantPoolHandle(THREAD, cp_oop);
1407 }
1408 cp->set_pool_holder(holder);
1409 cp->symbol_at_put(_imcp_invoke_name, name);
1410 cp->symbol_at_put(_imcp_invoke_signature, signature);
1411 cp->set_has_preresolution();
1412
1413 // decide on access bits: public or not?
1414 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1415 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1416 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1417 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1418
1419 methodHandle m;
1420 {
1421 InlineTableSizes sizes;
1422 Method* m_oop = Method::allocate(loader_data, 0,
1423 accessFlags_from(flags_bits), &sizes,
1424 ConstMethod::NORMAL, CHECK_(empty));
1425 m = methodHandle(THREAD, m_oop);
1426 }
1427 m->set_constants(cp());
1428 m->set_name_index(_imcp_invoke_name);
1429 m->set_signature_index(_imcp_invoke_signature);
1430 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1431 assert(m->signature() == signature, "");
1432 ResultTypeFinder rtf(signature);
1433 m->constMethod()->set_result_type(rtf.type());
1434 m->compute_size_of_parameters(THREAD);
1435 m->init_intrinsic_id();
1436 assert(m->is_method_handle_intrinsic(), "");
1437 #ifdef ASSERT
1438 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1439 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1440 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1441 #endif //ASSERT
1442
1443 // Finally, set up its entry points.
1444 assert(m->can_be_statically_bound(), "");
1445 m->set_vtable_index(Method::nonvirtual_vtable_index);
1446 m->link_method(m, CHECK_(empty));
1447
1448 if (TraceMethodHandles && (Verbose || WizardMode)) {
1449 ttyLocker ttyl;
1450 m->print_on(tty);
1451 }
1452
1453 return m;
1454 }
1455
1456 Klass* Method::check_non_bcp_klass(Klass* klass) {
1457 if (klass != NULL && klass->class_loader() != NULL) {
1458 if (klass->is_objArray_klass())
1459 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1460 return klass;
1461 }
1462 return NULL;
1463 }
1464
1465
1466 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1467 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1468 // Code below does not work for native methods - they should never get rewritten anyway
1469 assert(!m->is_native(), "cannot rewrite native methods");
1470 // Allocate new Method*
1471 AccessFlags flags = m->access_flags();
1472
1473 ConstMethod* cm = m->constMethod();
1474 int checked_exceptions_len = cm->checked_exceptions_length();
1475 int localvariable_len = cm->localvariable_table_length();
1476 int exception_table_len = cm->exception_table_length();
1477 int method_parameters_len = cm->method_parameters_length();
1478 int method_annotations_len = cm->method_annotations_length();
1479 int parameter_annotations_len = cm->parameter_annotations_length();
1480 int type_annotations_len = cm->type_annotations_length();
1481 int default_annotations_len = cm->default_annotations_length();
1482
1483 InlineTableSizes sizes(
1484 localvariable_len,
1485 new_compressed_linenumber_size,
1486 exception_table_len,
1487 checked_exceptions_len,
1488 method_parameters_len,
1489 cm->generic_signature_index(),
1490 method_annotations_len,
1491 parameter_annotations_len,
1492 type_annotations_len,
1493 default_annotations_len,
1494 0);
1495
1496 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1497 Method* newm_oop = Method::allocate(loader_data,
1498 new_code_length,
1499 flags,
1500 &sizes,
1501 m->method_type(),
1502 CHECK_(methodHandle()));
1503 methodHandle newm (THREAD, newm_oop);
1504
1505 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1506 ConstMethod* newcm = newm->constMethod();
1507 int new_const_method_size = newm->constMethod()->size();
1508
1509 // This works because the source and target are both Methods. Some compilers
1510 // (e.g., clang) complain that the target vtable pointer will be stomped,
1511 // so cast away newm()'s and m()'s Methodness.
1512 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1513
1514 // Create shallow copy of ConstMethod.
1515 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1516
1517 // Reset correct method/const method, method size, and parameter info
1518 newm->set_constMethod(newcm);
1519 newm->constMethod()->set_code_size(new_code_length);
1520 newm->constMethod()->set_constMethod_size(new_const_method_size);
1521 assert(newm->code_size() == new_code_length, "check");
1522 assert(newm->method_parameters_length() == method_parameters_len, "check");
1523 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1524 assert(newm->exception_table_length() == exception_table_len, "check");
1525 assert(newm->localvariable_table_length() == localvariable_len, "check");
1526 // Copy new byte codes
1527 memcpy(newm->code_base(), new_code, new_code_length);
1528 // Copy line number table
1529 if (new_compressed_linenumber_size > 0) {
1530 memcpy(newm->compressed_linenumber_table(),
1531 new_compressed_linenumber_table,
1532 new_compressed_linenumber_size);
1533 }
1534 // Copy method_parameters
1535 if (method_parameters_len > 0) {
1536 memcpy(newm->method_parameters_start(),
1537 m->method_parameters_start(),
1538 method_parameters_len * sizeof(MethodParametersElement));
1539 }
1540 // Copy checked_exceptions
1541 if (checked_exceptions_len > 0) {
1542 memcpy(newm->checked_exceptions_start(),
1543 m->checked_exceptions_start(),
1544 checked_exceptions_len * sizeof(CheckedExceptionElement));
1545 }
1546 // Copy exception table
1547 if (exception_table_len > 0) {
1548 memcpy(newm->exception_table_start(),
1549 m->exception_table_start(),
1550 exception_table_len * sizeof(ExceptionTableElement));
1551 }
1552 // Copy local variable number table
1553 if (localvariable_len > 0) {
1554 memcpy(newm->localvariable_table_start(),
1555 m->localvariable_table_start(),
1556 localvariable_len * sizeof(LocalVariableTableElement));
1557 }
1558 // Copy stackmap table
1559 if (m->has_stackmap_table()) {
1560 int code_attribute_length = m->stackmap_data()->length();
1561 Array<u1>* stackmap_data =
1562 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1563 memcpy((void*)stackmap_data->adr_at(0),
1564 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1565 newm->set_stackmap_data(stackmap_data);
1566 }
1567
1568 // copy annotations over to new method
1569 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1570 return newm;
1571 }
1572
1573 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1574 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1575 // because we are not loading from core libraries
1576 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1577 // which does not use the class default class loader so we check for its loader here
1578 const InstanceKlass* ik = InstanceKlass::cast(holder);
1579 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1580 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1581 }
1582
1583 // see if the klass name is well-known:
1584 Symbol* klass_name = ik->name();
1585 return vmSymbols::find_sid(klass_name);
1586 }
1587
1588 void Method::init_intrinsic_id() {
1589 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1590 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1591 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1592 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1593
1594 // the klass name is well-known:
1595 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1596 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1597
1598 // ditto for method and signature:
1599 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1600 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1601 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1602 && name_id == vmSymbols::NO_SID) {
1603 return;
1604 }
1605 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1606 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1607 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1608 && sig_id == vmSymbols::NO_SID) {
1609 return;
1610 }
1611 jshort flags = access_flags().as_short();
1612
1613 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1614 if (id != vmIntrinsics::_none) {
1615 set_intrinsic_id(id);
1616 if (id == vmIntrinsics::_Class_cast) {
1617 // Even if the intrinsic is rejected, we want to inline this simple method.
1618 set_force_inline(true);
1619 }
1620 return;
1621 }
1622
1623 // A few slightly irregular cases:
1624 switch (klass_id) {
1625 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1626 // Second chance: check in regular Math.
1627 switch (name_id) {
1628 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1629 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1630 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1631 // pretend it is the corresponding method in the non-strict class:
1632 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1633 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1634 break;
1635 default:
1636 break;
1637 }
1638 break;
1639
1640 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1641 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1642 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1643 if (!is_native()) break;
1644 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1645 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1646 id = vmIntrinsics::_none;
1647 break;
1648
1649 default:
1650 break;
1651 }
1652
1653 if (id != vmIntrinsics::_none) {
1654 // Set up its iid. It is an alias method.
1655 set_intrinsic_id(id);
1656 return;
1657 }
1658 }
1659
1660 // These two methods are static since a GC may move the Method
1661 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1662 if (!THREAD->can_call_java()) {
1663 // There is nothing useful this routine can do from within the Compile thread.
1664 // Hopefully, the signature contains only well-known classes.
1665 // We could scan for this and return true/false, but the caller won't care.
1666 return false;
1667 }
1668 bool sig_is_loaded = true;
1669 Handle class_loader(THREAD, m->method_holder()->class_loader());
1670 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1671 ResourceMark rm(THREAD);
1672 Symbol* signature = m->signature();
1673 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1674 if (ss.is_object()) {
1675 Symbol* sym = ss.as_symbol();
1676 Symbol* name = sym;
1677 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1678 protection_domain, THREAD);
1679 // We are loading classes eagerly. If a ClassNotFoundException or
1680 // a LinkageError was generated, be sure to ignore it.
1681 if (HAS_PENDING_EXCEPTION) {
1682 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1683 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1684 CLEAR_PENDING_EXCEPTION;
1685 } else {
1686 return false;
1687 }
1688 }
1689 if( klass == NULL) { sig_is_loaded = false; }
1690 }
1691 }
1692 return sig_is_loaded;
1693 }
1694
1695 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1696 Handle class_loader(THREAD, m->method_holder()->class_loader());
1697 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1698 ResourceMark rm(THREAD);
1699 Symbol* signature = m->signature();
1700 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1701 if (ss.type() == T_OBJECT) {
1702 Symbol* name = ss.as_symbol_or_null();
1703 if (name == NULL) return true;
1704 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1705 if (klass == NULL) return true;
1706 }
1707 }
1708 return false;
1709 }
1710
1711 // Exposed so field engineers can debug VM
1712 void Method::print_short_name(outputStream* st) {
1713 ResourceMark rm;
1714 #ifdef PRODUCT
1715 st->print(" %s::", method_holder()->external_name());
1716 #else
1717 st->print(" %s::", method_holder()->internal_name());
1718 #endif
1719 name()->print_symbol_on(st);
1720 if (WizardMode) signature()->print_symbol_on(st);
1721 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1722 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1723 }
1724
1725 // Comparer for sorting an object array containing
1726 // Method*s.
1727 static int method_comparator(Method* a, Method* b) {
1728 return a->name()->fast_compare(b->name());
1729 }
1730
1731 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1732 // default_methods also uses this without the ordering for fast find_method
1733 void Method::sort_methods(Array<Method*>* methods, bool set_idnums) {
1734 int length = methods->length();
1735 if (length > 1) {
1736 {
1737 NoSafepointVerifier nsv;
1738 QuickSort::sort(methods->data(), length, method_comparator, /*idempotent=*/false);
1739 }
1740 // Reset method ordering
1741 if (set_idnums) {
1742 for (int i = 0; i < length; i++) {
1743 Method* m = methods->at(i);
1744 m->set_method_idnum(i);
1745 m->set_orig_method_idnum(i);
1746 }
1747 }
1748 }
1749 }
1750
1751 //-----------------------------------------------------------------------------------
1752 // Non-product code unless JVM/TI needs it
1753
1754 #if !defined(PRODUCT) || INCLUDE_JVMTI
1755 class SignatureTypePrinter : public SignatureTypeNames {
1756 private:
1757 outputStream* _st;
1758 bool _use_separator;
1759
1760 void type_name(const char* name) {
1761 if (_use_separator) _st->print(", ");
1762 _st->print("%s", name);
1763 _use_separator = true;
1764 }
1765
1766 public:
1767 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1768 _st = st;
1769 _use_separator = false;
1770 }
1771
1772 void print_parameters() { _use_separator = false; iterate_parameters(); }
1773 void print_returntype() { _use_separator = false; iterate_returntype(); }
1774 };
1775
1776
1777 void Method::print_name(outputStream* st) {
1778 Thread *thread = Thread::current();
1779 ResourceMark rm(thread);
1780 st->print("%s ", is_static() ? "static" : "virtual");
1781 if (WizardMode) {
1782 st->print("%s.", method_holder()->internal_name());
1783 name()->print_symbol_on(st);
1784 signature()->print_symbol_on(st);
1785 } else {
1786 SignatureTypePrinter sig(signature(), st);
1787 sig.print_returntype();
1788 st->print(" %s.", method_holder()->internal_name());
1789 name()->print_symbol_on(st);
1790 st->print("(");
1791 sig.print_parameters();
1792 st->print(")");
1793 }
1794 }
1795 #endif // !PRODUCT || INCLUDE_JVMTI
1796
1797
1798 void Method::print_codes_on(outputStream* st) const {
1799 print_codes_on(0, code_size(), st);
1800 }
1801
1802 void Method::print_codes_on(int from, int to, outputStream* st) const {
1803 Thread *thread = Thread::current();
1804 ResourceMark rm(thread);
1805 methodHandle mh (thread, (Method*)this);
1806 BytecodeStream s(mh);
1807 s.set_interval(from, to);
1808 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1809 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1810 }
1811
1812 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1813 _bci = 0;
1814 _line = 0;
1815 };
1816
1817 bool CompressedLineNumberReadStream::read_pair() {
1818 jubyte next = read_byte();
1819 // Check for terminator
1820 if (next == 0) return false;
1821 if (next == 0xFF) {
1822 // Escape character, regular compression used
1823 _bci += read_signed_int();
1824 _line += read_signed_int();
1825 } else {
1826 // Single byte compression used
1827 _bci += next >> 3;
1828 _line += next & 0x7;
1829 }
1830 return true;
1831 }
1832
1833 #if INCLUDE_JVMTI
1834
1835 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1836 BreakpointInfo* bp = method_holder()->breakpoints();
1837 for (; bp != NULL; bp = bp->next()) {
1838 if (bp->match(this, bci)) {
1839 return bp->orig_bytecode();
1840 }
1841 }
1842 {
1843 ResourceMark rm;
1844 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1845 }
1846 return Bytecodes::_shouldnotreachhere;
1847 }
1848
1849 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1850 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1851 BreakpointInfo* bp = method_holder()->breakpoints();
1852 for (; bp != NULL; bp = bp->next()) {
1853 if (bp->match(this, bci)) {
1854 bp->set_orig_bytecode(code);
1855 // and continue, in case there is more than one
1856 }
1857 }
1858 }
1859
1860 void Method::set_breakpoint(int bci) {
1861 InstanceKlass* ik = method_holder();
1862 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1863 bp->set_next(ik->breakpoints());
1864 ik->set_breakpoints(bp);
1865 // do this last:
1866 bp->set(this);
1867 }
1868
1869 static void clear_matches(Method* m, int bci) {
1870 InstanceKlass* ik = m->method_holder();
1871 BreakpointInfo* prev_bp = NULL;
1872 BreakpointInfo* next_bp;
1873 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1874 next_bp = bp->next();
1875 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1876 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1877 // do this first:
1878 bp->clear(m);
1879 // unhook it
1880 if (prev_bp != NULL)
1881 prev_bp->set_next(next_bp);
1882 else
1883 ik->set_breakpoints(next_bp);
1884 delete bp;
1885 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1886 // at same location. So we have multiple matching (method_index and bci)
1887 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1888 // breakpoint for clear_breakpoint request and keep all other method versions
1889 // BreakpointInfo for future clear_breakpoint request.
1890 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1891 // which is being called when class is unloaded. We delete all the Breakpoint
1892 // information for all versions of method. We may not correctly restore the original
1893 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1894 // so these methods won't be used anymore.
1895 if (bci >= 0) {
1896 break;
1897 }
1898 } else {
1899 // This one is a keeper.
1900 prev_bp = bp;
1901 }
1902 }
1903 }
1904
1905 void Method::clear_breakpoint(int bci) {
1906 assert(bci >= 0, "");
1907 clear_matches(this, bci);
1908 }
1909
1910 void Method::clear_all_breakpoints() {
1911 clear_matches(this, -1);
1912 }
1913
1914 #endif // INCLUDE_JVMTI
1915
1916 int Method::invocation_count() {
1917 MethodCounters *mcs = method_counters();
1918 if (TieredCompilation) {
1919 MethodData* const mdo = method_data();
1920 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1921 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1922 return InvocationCounter::count_limit;
1923 } else {
1924 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1925 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1926 }
1927 } else {
1928 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1929 }
1930 }
1931
1932 int Method::backedge_count() {
1933 MethodCounters *mcs = method_counters();
1934 if (TieredCompilation) {
1935 MethodData* const mdo = method_data();
1936 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1937 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1938 return InvocationCounter::count_limit;
1939 } else {
1940 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1941 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1942 }
1943 } else {
1944 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1945 }
1946 }
1947
1948 int Method::highest_comp_level() const {
1949 const MethodCounters* mcs = method_counters();
1950 if (mcs != NULL) {
1951 return mcs->highest_comp_level();
1952 } else {
1953 return CompLevel_none;
1954 }
1955 }
1956
1957 int Method::highest_osr_comp_level() const {
1958 const MethodCounters* mcs = method_counters();
1959 if (mcs != NULL) {
1960 return mcs->highest_osr_comp_level();
1961 } else {
1962 return CompLevel_none;
1963 }
1964 }
1965
1966 void Method::set_highest_comp_level(int level) {
1967 MethodCounters* mcs = method_counters();
1968 if (mcs != NULL) {
1969 mcs->set_highest_comp_level(level);
1970 }
1971 }
1972
1973 void Method::set_highest_osr_comp_level(int level) {
1974 MethodCounters* mcs = method_counters();
1975 if (mcs != NULL) {
1976 mcs->set_highest_osr_comp_level(level);
1977 }
1978 }
1979
1980 #if INCLUDE_JVMTI
1981
1982 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1983 _bci = bci;
1984 _name_index = m->name_index();
1985 _signature_index = m->signature_index();
1986 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1987 if (_orig_bytecode == Bytecodes::_breakpoint)
1988 _orig_bytecode = m->orig_bytecode_at(_bci);
1989 _next = NULL;
1990 }
1991
1992 void BreakpointInfo::set(Method* method) {
1993 #ifdef ASSERT
1994 {
1995 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1996 if (code == Bytecodes::_breakpoint)
1997 code = method->orig_bytecode_at(_bci);
1998 assert(orig_bytecode() == code, "original bytecode must be the same");
1999 }
2000 #endif
2001 Thread *thread = Thread::current();
2002 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
2003 method->incr_number_of_breakpoints(thread);
2004 SystemDictionary::notice_modification();
2005 {
2006 // Deoptimize all dependents on this method
2007 HandleMark hm(thread);
2008 methodHandle mh(thread, method);
2009 CodeCache::flush_dependents_on_method(mh);
2010 }
2011 }
2012
2013 void BreakpointInfo::clear(Method* method) {
2014 *method->bcp_from(_bci) = orig_bytecode();
2015 assert(method->number_of_breakpoints() > 0, "must not go negative");
2016 method->decr_number_of_breakpoints(Thread::current());
2017 }
2018
2019 #endif // INCLUDE_JVMTI
2020
2021 // jmethodID handling
2022
2023 // This is a block allocating object, sort of like JNIHandleBlock, only a
2024 // lot simpler.
2025 // It's allocated on the CHeap because once we allocate a jmethodID, we can
2026 // never get rid of it.
2027
2028 static const int min_block_size = 8;
2029
2030 class JNIMethodBlockNode : public CHeapObj<mtClass> {
2031 friend class JNIMethodBlock;
2032 Method** _methods;
2033 int _number_of_methods;
2034 int _top;
2035 JNIMethodBlockNode* _next;
2036
2037 public:
2038
2039 JNIMethodBlockNode(int num_methods = min_block_size);
2040
2041 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
2042
2043 void ensure_methods(int num_addl_methods) {
2044 if (_top < _number_of_methods) {
2045 num_addl_methods -= _number_of_methods - _top;
2046 if (num_addl_methods <= 0) {
2047 return;
2048 }
2049 }
2050 if (_next == NULL) {
2051 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
2052 } else {
2053 _next->ensure_methods(num_addl_methods);
2054 }
2055 }
2056 };
2057
2058 class JNIMethodBlock : public CHeapObj<mtClass> {
2059 JNIMethodBlockNode _head;
2060 JNIMethodBlockNode *_last_free;
2061 public:
2062 static Method* const _free_method;
2063
2064 JNIMethodBlock(int initial_capacity = min_block_size)
2065 : _head(initial_capacity), _last_free(&_head) {}
2066
2067 void ensure_methods(int num_addl_methods) {
2068 _last_free->ensure_methods(num_addl_methods);
2069 }
2070
2071 Method** add_method(Method* m) {
2072 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2073 if (b->_top < b->_number_of_methods) {
2074 // top points to the next free entry.
2075 int i = b->_top;
2076 b->_methods[i] = m;
2077 b->_top++;
2078 _last_free = b;
2079 return &(b->_methods[i]);
2080 } else if (b->_top == b->_number_of_methods) {
2081 // if the next free entry ran off the block see if there's a free entry
2082 for (int i = 0; i < b->_number_of_methods; i++) {
2083 if (b->_methods[i] == _free_method) {
2084 b->_methods[i] = m;
2085 _last_free = b;
2086 return &(b->_methods[i]);
2087 }
2088 }
2089 // Only check each block once for frees. They're very unlikely.
2090 // Increment top past the end of the block.
2091 b->_top++;
2092 }
2093 // need to allocate a next block.
2094 if (b->_next == NULL) {
2095 b->_next = _last_free = new JNIMethodBlockNode();
2096 }
2097 }
2098 guarantee(false, "Should always allocate a free block");
2099 return NULL;
2100 }
2101
2102 bool contains(Method** m) {
2103 if (m == NULL) return false;
2104 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2105 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2106 // This is a bit of extra checking, for two reasons. One is
2107 // that contains() deals with pointers that are passed in by
2108 // JNI code, so making sure that the pointer is aligned
2109 // correctly is valuable. The other is that <= and > are
2110 // technically not defined on pointers, so the if guard can
2111 // pass spuriously; no modern compiler is likely to make that
2112 // a problem, though (and if one did, the guard could also
2113 // fail spuriously, which would be bad).
2114 ptrdiff_t idx = m - b->_methods;
2115 if (b->_methods + idx == m) {
2116 return true;
2117 }
2118 }
2119 }
2120 return false; // not found
2121 }
2122
2123 // Doesn't really destroy it, just marks it as free so it can be reused.
2124 void destroy_method(Method** m) {
2125 #ifdef ASSERT
2126 assert(contains(m), "should be a methodID");
2127 #endif // ASSERT
2128 *m = _free_method;
2129 }
2130
2131 // During class unloading the methods are cleared, which is different
2132 // than freed.
2133 void clear_all_methods() {
2134 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2135 for (int i = 0; i< b->_number_of_methods; i++) {
2136 b->_methods[i] = NULL;
2137 }
2138 }
2139 }
2140 #ifndef PRODUCT
2141 int count_methods() {
2142 // count all allocated methods
2143 int count = 0;
2144 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2145 for (int i = 0; i< b->_number_of_methods; i++) {
2146 if (b->_methods[i] != _free_method) count++;
2147 }
2148 }
2149 return count;
2150 }
2151 #endif // PRODUCT
2152 };
2153
2154 // Something that can't be mistaken for an address or a markOop
2155 Method* const JNIMethodBlock::_free_method = (Method*)55;
2156
2157 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2158 _number_of_methods = MAX2(num_methods, min_block_size);
2159 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2160 for (int i = 0; i < _number_of_methods; i++) {
2161 _methods[i] = JNIMethodBlock::_free_method;
2162 }
2163 }
2164
2165 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2166 ClassLoaderData* cld = loader_data;
2167 if (!SafepointSynchronize::is_at_safepoint()) {
2168 // Have to add jmethod_ids() to class loader data thread-safely.
2169 // Also have to add the method to the list safely, which the cld lock
2170 // protects as well.
2171 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2172 if (cld->jmethod_ids() == NULL) {
2173 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2174 } else {
2175 cld->jmethod_ids()->ensure_methods(capacity);
2176 }
2177 } else {
2178 // At safepoint, we are single threaded and can set this.
2179 if (cld->jmethod_ids() == NULL) {
2180 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2181 } else {
2182 cld->jmethod_ids()->ensure_methods(capacity);
2183 }
2184 }
2185 }
2186
2187 // Add a method id to the jmethod_ids
2188 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2189 ClassLoaderData* cld = loader_data;
2190
2191 if (!SafepointSynchronize::is_at_safepoint()) {
2192 // Have to add jmethod_ids() to class loader data thread-safely.
2193 // Also have to add the method to the list safely, which the cld lock
2194 // protects as well.
2195 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2196 if (cld->jmethod_ids() == NULL) {
2197 cld->set_jmethod_ids(new JNIMethodBlock());
2198 }
2199 // jmethodID is a pointer to Method*
2200 return (jmethodID)cld->jmethod_ids()->add_method(m);
2201 } else {
2202 // At safepoint, we are single threaded and can set this.
2203 if (cld->jmethod_ids() == NULL) {
2204 cld->set_jmethod_ids(new JNIMethodBlock());
2205 }
2206 // jmethodID is a pointer to Method*
2207 return (jmethodID)cld->jmethod_ids()->add_method(m);
2208 }
2209 }
2210
2211 // Mark a jmethodID as free. This is called when there is a data race in
2212 // InstanceKlass while creating the jmethodID cache.
2213 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2214 ClassLoaderData* cld = loader_data;
2215 Method** ptr = (Method**)m;
2216 assert(cld->jmethod_ids() != NULL, "should have method handles");
2217 cld->jmethod_ids()->destroy_method(ptr);
2218 }
2219
2220 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2221 // Can't assert the method_holder is the same because the new method has the
2222 // scratch method holder.
2223 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2224 == new_method->method_holder()->class_loader() ||
2225 new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2226 "changing to a different class loader");
2227 // Just change the method in place, jmethodID pointer doesn't change.
2228 *((Method**)jmid) = new_method;
2229 }
2230
2231 bool Method::is_method_id(jmethodID mid) {
2232 Method* m = resolve_jmethod_id(mid);
2233 assert(m != NULL, "should be called with non-null method");
2234 InstanceKlass* ik = m->method_holder();
2235 ClassLoaderData* cld = ik->class_loader_data();
2236 if (cld->jmethod_ids() == NULL) return false;
2237 return (cld->jmethod_ids()->contains((Method**)mid));
2238 }
2239
2240 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2241 if (mid == NULL) return NULL;
2242 Method* o = resolve_jmethod_id(mid);
2243 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2244 return NULL;
2245 }
2246 return o;
2247 };
2248
2249 void Method::set_on_stack(const bool value) {
2250 // Set both the method itself and its constant pool. The constant pool
2251 // on stack means some method referring to it is also on the stack.
2252 constants()->set_on_stack(value);
2253
2254 bool already_set = on_stack();
2255 _access_flags.set_on_stack(value);
2256 if (value && !already_set) {
2257 MetadataOnStackMark::record(this);
2258 }
2259 assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2260 "emcp methods cannot run after emcp bit is cleared");
2261 }
2262
2263 // Called when the class loader is unloaded to make all methods weak.
2264 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2265 loader_data->jmethod_ids()->clear_all_methods();
2266 }
2267
2268 bool Method::has_method_vptr(const void* ptr) {
2269 Method m;
2270 // This assumes that the vtbl pointer is the first word of a C++ object.
2271 return dereference_vptr(&m) == dereference_vptr(ptr);
2272 }
2273
2274 // Check that this pointer is valid by checking that the vtbl pointer matches
2275 bool Method::is_valid_method(const Method* m) {
2276 if (m == NULL) {
2277 return false;
2278 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2279 // Quick sanity check on pointer.
2280 return false;
2281 } else if (m->is_shared()) {
2282 return MetaspaceShared::is_valid_shared_method(m);
2283 } else if (Metaspace::contains_non_shared(m)) {
2284 return has_method_vptr((const void*)m);
2285 } else {
2286 return false;
2287 }
2288 }
2289
2290 #ifndef PRODUCT
2291 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2292 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2293 }
2294 #endif // PRODUCT
2295
2296
2297 // Printing
2298
2299 #ifndef PRODUCT
2300
2301 void Method::print_on(outputStream* st) const {
2302 ResourceMark rm;
2303 assert(is_method(), "must be method");
2304 st->print_cr("%s", internal_name());
2305 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2306 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2307 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2308 constants()->print_value_on(st); st->cr();
2309 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2310 st->print (" - name: "); name()->print_value_on(st); st->cr();
2311 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2312 st->print_cr(" - max stack: %d", max_stack());
2313 st->print_cr(" - max locals: %d", max_locals());
2314 st->print_cr(" - size of params: %d", size_of_parameters());
2315 st->print_cr(" - method size: %d", method_size());
2316 if (intrinsic_id() != vmIntrinsics::_none)
2317 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2318 if (highest_comp_level() != CompLevel_none)
2319 st->print_cr(" - highest level: %d", highest_comp_level());
2320 st->print_cr(" - vtable index: %d", _vtable_index);
2321 if (valid_itable_index())
2322 st->print_cr(" - itable index: %d", itable_index());
2323 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2324 st->print( " - adapters: ");
2325 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2326 if (a == NULL)
2327 st->print_cr(INTPTR_FORMAT, p2i(a));
2328 else
2329 a->print_adapter_on(st);
2330 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2331 st->print_cr(" - code size: %d", code_size());
2332 if (code_size() != 0) {
2333 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2334 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2335 }
2336 if (method_data() != NULL) {
2337 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2338 }
2339 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2340 if (checked_exceptions_length() > 0) {
2341 CheckedExceptionElement* table = checked_exceptions_start();
2342 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2343 if (Verbose) {
2344 for (int i = 0; i < checked_exceptions_length(); i++) {
2345 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2346 }
2347 }
2348 }
2349 if (has_linenumber_table()) {
2350 u_char* table = compressed_linenumber_table();
2351 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2352 if (Verbose) {
2353 CompressedLineNumberReadStream stream(table);
2354 while (stream.read_pair()) {
2355 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2356 }
2357 }
2358 }
2359 st->print_cr(" - localvar length: %d", localvariable_table_length());
2360 if (localvariable_table_length() > 0) {
2361 LocalVariableTableElement* table = localvariable_table_start();
2362 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2363 if (Verbose) {
2364 for (int i = 0; i < localvariable_table_length(); i++) {
2365 int bci = table[i].start_bci;
2366 int len = table[i].length;
2367 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2368 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2369 int slot = table[i].slot;
2370 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2371 }
2372 }
2373 }
2374 if (code() != NULL) {
2375 st->print (" - compiled code: ");
2376 code()->print_value_on(st);
2377 }
2378 if (is_native()) {
2379 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2380 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2381 }
2382 }
2383
2384 void Method::print_linkage_flags(outputStream* st) {
2385 access_flags().print_on(st);
2386 if (is_default_method()) {
2387 st->print("default ");
2388 }
2389 if (is_overpass()) {
2390 st->print("overpass ");
2391 }
2392 }
2393 #endif //PRODUCT
2394
2395 void Method::print_value_on(outputStream* st) const {
2396 assert(is_method(), "must be method");
2397 st->print("%s", internal_name());
2398 print_address_on(st);
2399 st->print(" ");
2400 if (WizardMode) access_flags().print_on(st);
2401 name()->print_value_on(st);
2402 st->print(" ");
2403 signature()->print_value_on(st);
2404 st->print(" in ");
2405 method_holder()->print_value_on(st);
2406 if (WizardMode) st->print("#%d", _vtable_index);
2407 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2408 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2409 }
2410
2411 #if INCLUDE_SERVICES
2412 // Size Statistics
2413 void Method::collect_statistics(KlassSizeStats *sz) const {
2414 int mysize = sz->count(this);
2415 sz->_method_bytes += mysize;
2416 sz->_method_all_bytes += mysize;
2417 sz->_rw_bytes += mysize;
2418
2419 if (constMethod()) {
2420 constMethod()->collect_statistics(sz);
2421 }
2422 if (method_data()) {
2423 method_data()->collect_statistics(sz);
2424 }
2425 }
2426 #endif // INCLUDE_SERVICES
2427
2428 // LogTouchedMethods and PrintTouchedMethods
2429
2430 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2431 // the Method may be garbage collected. Let's roll our own hash table.
2432 class TouchedMethodRecord : CHeapObj<mtTracing> {
2433 public:
2434 // It's OK to store Symbols here because they will NOT be GC'ed if
2435 // LogTouchedMethods is enabled.
2436 TouchedMethodRecord* _next;
2437 Symbol* _class_name;
2438 Symbol* _method_name;
2439 Symbol* _method_signature;
2440 };
2441
2442 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2443 static TouchedMethodRecord** _touched_method_table = NULL;
2444
2445 void Method::log_touched(TRAPS) {
2446
2447 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2448 Symbol* my_class = klass_name();
2449 Symbol* my_name = name();
2450 Symbol* my_sig = signature();
2451
2452 unsigned int hash = my_class->identity_hash() +
2453 my_name->identity_hash() +
2454 my_sig->identity_hash();
2455 juint index = juint(hash) % table_size;
2456
2457 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2458 if (_touched_method_table == NULL) {
2459 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2460 mtTracing, CURRENT_PC);
2461 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2462 }
2463
2464 TouchedMethodRecord* ptr = _touched_method_table[index];
2465 while (ptr) {
2466 if (ptr->_class_name == my_class &&
2467 ptr->_method_name == my_name &&
2468 ptr->_method_signature == my_sig) {
2469 return;
2470 }
2471 if (ptr->_next == NULL) break;
2472 ptr = ptr->_next;
2473 }
2474 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2475 my_class->increment_refcount();
2476 my_name->increment_refcount();
2477 my_sig->increment_refcount();
2478 nptr->_class_name = my_class;
2479 nptr->_method_name = my_name;
2480 nptr->_method_signature = my_sig;
2481 nptr->_next = NULL;
2482
2483 if (ptr == NULL) {
2484 // first
2485 _touched_method_table[index] = nptr;
2486 } else {
2487 ptr->_next = nptr;
2488 }
2489 }
2490
2491 void Method::print_touched_methods(outputStream* out) {
2492 MutexLocker ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2493 out->print_cr("# Method::print_touched_methods version 1");
2494 if (_touched_method_table) {
2495 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2496 TouchedMethodRecord* ptr = _touched_method_table[i];
2497 while(ptr) {
2498 ptr->_class_name->print_symbol_on(out); out->print(".");
2499 ptr->_method_name->print_symbol_on(out); out->print(":");
2500 ptr->_method_signature->print_symbol_on(out); out->cr();
2501 ptr = ptr->_next;
2502 }
2503 }
2504 }
2505 }
2506
2507 // Verification
2508
2509 void Method::verify_on(outputStream* st) {
2510 guarantee(is_method(), "object must be method");
2511 guarantee(constants()->is_constantPool(), "should be constant pool");
2512 MethodData* md = method_data();
2513 guarantee(md == NULL ||
2514 md->is_methodData(), "should be method data");
2515 }