1 /*
2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/metadataOnStackMark.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "code/codeCache.hpp"
29 #include "code/debugInfoRec.hpp"
30 #include "gc/shared/collectedHeap.inline.hpp"
31 #include "gc/shared/gcLocker.hpp"
32 #include "gc/shared/generation.hpp"
33 #include "interpreter/bytecodeStream.hpp"
34 #include "interpreter/bytecodeTracer.hpp"
35 #include "interpreter/bytecodes.hpp"
36 #include "interpreter/interpreter.hpp"
37 #include "interpreter/oopMapCache.hpp"
38 #include "memory/heapInspection.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/metaspaceShared.hpp"
41 #include "memory/oopFactory.hpp"
42 #include "memory/resourceArea.hpp"
43 #include "memory/vtBuffer.hpp"
44 #include "oops/constMethod.hpp"
45 #include "oops/method.hpp"
46 #include "oops/methodData.hpp"
47 #include "oops/objArrayOop.inline.hpp"
48 #include "oops/oop.inline.hpp"
49 #include "oops/symbol.hpp"
50 #include "oops/valueKlass.hpp"
51 #include "prims/jvmtiExport.hpp"
52 #include "prims/methodHandles.hpp"
53 #include "prims/nativeLookup.hpp"
54 #include "runtime/arguments.hpp"
55 #include "runtime/compilationPolicy.hpp"
56 #include "runtime/frame.inline.hpp"
57 #include "runtime/handles.inline.hpp"
58 #include "runtime/init.hpp"
59 #include "runtime/orderAccess.inline.hpp"
60 #include "runtime/relocator.hpp"
61 #include "runtime/sharedRuntime.hpp"
62 #include "runtime/signature.hpp"
63 #include "utilities/quickSort.hpp"
64 #include "utilities/xmlstream.hpp"
65
66 // Implementation of Method
67
68 Method* Method::allocate(ClassLoaderData* loader_data,
69 int byte_code_size,
70 AccessFlags access_flags,
71 InlineTableSizes* sizes,
72 ConstMethod::MethodType method_type,
73 TRAPS) {
74 assert(!access_flags.is_native() || byte_code_size == 0,
75 "native methods should not contain byte codes");
76 ConstMethod* cm = ConstMethod::allocate(loader_data,
77 byte_code_size,
78 sizes,
79 method_type,
80 CHECK_NULL);
81 int size = Method::size(access_flags.is_native());
82 return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
83 }
84
85 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
86 NoSafepointVerifier no_safepoint;
87 set_constMethod(xconst);
88 set_access_flags(access_flags);
89 set_intrinsic_id(vmIntrinsics::_none);
90 set_force_inline(false);
91 set_hidden(false);
92 set_dont_inline(false);
93 set_has_injected_profile(false);
94 set_method_data(NULL);
95 clear_method_counters();
96 set_vtable_index(Method::garbage_vtable_index);
97
98 // Fix and bury in Method*
99 set_interpreter_entry(NULL); // sets i2i entry and from_int
100 set_adapter_entry(NULL);
101 clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
102
103 if (access_flags.is_native()) {
104 clear_native_function();
105 set_signature_handler(NULL);
106 }
107
108 initialize_max_vt_buffer();
109
110 NOT_PRODUCT(set_compiled_invocation_count(0);)
111 }
112
113 // Release Method*. The nmethod will be gone when we get here because
114 // we've walked the code cache.
115 void Method::deallocate_contents(ClassLoaderData* loader_data) {
116 MetadataFactory::free_metadata(loader_data, constMethod());
117 set_constMethod(NULL);
118 MetadataFactory::free_metadata(loader_data, method_data());
119 set_method_data(NULL);
120 MetadataFactory::free_metadata(loader_data, method_counters());
121 clear_method_counters();
122 // The nmethod will be gone when we get here.
123 if (code() != NULL) _code = NULL;
124 }
125
126 address Method::get_i2c_entry() {
127 assert(adapter() != NULL, "must have");
128 return adapter()->get_i2c_entry();
129 }
130
131 address Method::get_c2i_entry() {
132 assert(adapter() != NULL, "must have");
133 return adapter()->get_c2i_entry();
134 }
135
136 address Method::get_c2i_unverified_entry() {
137 assert(adapter() != NULL, "must have");
138 return adapter()->get_c2i_unverified_entry();
139 }
140
141 char* Method::name_and_sig_as_C_string() const {
142 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
143 }
144
145 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
146 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
147 }
148
149 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
150 const char* klass_name = klass->external_name();
151 int klass_name_len = (int)strlen(klass_name);
152 int method_name_len = method_name->utf8_length();
153 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
154 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
155 strcpy(dest, klass_name);
156 dest[klass_name_len] = '.';
157 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
158 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
159 dest[len] = 0;
160 return dest;
161 }
162
163 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
164 Symbol* klass_name = klass->name();
165 klass_name->as_klass_external_name(buf, size);
166 int len = (int)strlen(buf);
167
168 if (len < size - 1) {
169 buf[len++] = '.';
170
171 method_name->as_C_string(&(buf[len]), size - len);
172 len = (int)strlen(buf);
173
174 signature->as_C_string(&(buf[len]), size - len);
175 }
176
177 return buf;
178 }
179
180 int Method::fast_exception_handler_bci_for(methodHandle mh, Klass* ex_klass, int throw_bci, TRAPS) {
181 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
182 // access exception table
183 ExceptionTable table(mh());
184 int length = table.length();
185 // iterate through all entries sequentially
186 constantPoolHandle pool(THREAD, mh->constants());
187 for (int i = 0; i < length; i ++) {
188 //reacquire the table in case a GC happened
189 ExceptionTable table(mh());
190 int beg_bci = table.start_pc(i);
191 int end_bci = table.end_pc(i);
192 assert(beg_bci <= end_bci, "inconsistent exception table");
193 if (beg_bci <= throw_bci && throw_bci < end_bci) {
194 // exception handler bci range covers throw_bci => investigate further
195 int handler_bci = table.handler_pc(i);
196 int klass_index = table.catch_type_index(i);
197 if (klass_index == 0) {
198 return handler_bci;
199 } else if (ex_klass == NULL) {
200 return handler_bci;
201 } else {
202 // we know the exception class => get the constraint class
203 // this may require loading of the constraint class; if verification
204 // fails or some other exception occurs, return handler_bci
205 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
206 assert(k != NULL, "klass not loaded");
207 if (ex_klass->is_subtype_of(k)) {
208 return handler_bci;
209 }
210 }
211 }
212 }
213
214 return -1;
215 }
216
217 void Method::mask_for(int bci, InterpreterOopMap* mask) {
218
219 Thread* myThread = Thread::current();
220 methodHandle h_this(myThread, this);
221 #if defined(ASSERT) && !INCLUDE_JVMCI
222 bool has_capability = myThread->is_VM_thread() ||
223 myThread->is_ConcurrentGC_thread() ||
224 myThread->is_GC_task_thread();
225
226 if (!has_capability) {
227 if (!VerifyStack && !VerifyLastFrame) {
228 // verify stack calls this outside VM thread
229 warning("oopmap should only be accessed by the "
230 "VM, GC task or CMS threads (or during debugging)");
231 InterpreterOopMap local_mask;
232 method_holder()->mask_for(h_this, bci, &local_mask);
233 local_mask.print();
234 }
235 }
236 #endif
237 method_holder()->mask_for(h_this, bci, mask);
238 return;
239 }
240
241
242 int Method::bci_from(address bcp) const {
243 if (is_native() && bcp == 0) {
244 return 0;
245 }
246 #ifdef ASSERT
247 {
248 ResourceMark rm;
249 assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
250 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
251 p2i(bcp), name_and_sig_as_C_string());
252 }
253 #endif
254 return bcp - code_base();
255 }
256
257
258 int Method::validate_bci(int bci) const {
259 return (bci == 0 || bci < code_size()) ? bci : -1;
260 }
261
262 // Return bci if it appears to be a valid bcp
263 // Return -1 otherwise.
264 // Used by profiling code, when invalid data is a possibility.
265 // The caller is responsible for validating the Method* itself.
266 int Method::validate_bci_from_bcp(address bcp) const {
267 // keep bci as -1 if not a valid bci
268 int bci = -1;
269 if (bcp == 0 || bcp == code_base()) {
270 // code_size() may return 0 and we allow 0 here
271 // the method may be native
272 bci = 0;
273 } else if (contains(bcp)) {
274 bci = bcp - code_base();
275 }
276 // Assert that if we have dodged any asserts, bci is negative.
277 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
278 return bci;
279 }
280
281 address Method::bcp_from(int bci) const {
282 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
283 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
284 address bcp = code_base() + bci;
285 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
286 return bcp;
287 }
288
289 address Method::bcp_from(address bcp) const {
290 if (is_native() && bcp == NULL) {
291 return code_base();
292 } else {
293 return bcp;
294 }
295 }
296
297 int Method::size(bool is_native) {
298 // If native, then include pointers for native_function and signature_handler
299 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
300 int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
301 return align_metadata_size(header_size() + extra_words);
302 }
303
304
305 Symbol* Method::klass_name() const {
306 return method_holder()->name();
307 }
308
309
310 // Attempt to return method oop to original state. Clear any pointers
311 // (to objects outside the shared spaces). We won't be able to predict
312 // where they should point in a new JVM. Further initialize some
313 // entries now in order allow them to be write protected later.
314
315 void Method::remove_unshareable_info() {
316 unlink_method();
317 }
318
319 void Method::set_vtable_index(int index) {
320 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
321 // At runtime initialize_vtable is rerun as part of link_class_impl()
322 // for a shared class loaded by the non-boot loader to obtain the loader
323 // constraints based on the runtime classloaders' context.
324 return; // don't write into the shared class
325 } else {
326 _vtable_index = index;
327 }
328 }
329
330 void Method::set_itable_index(int index) {
331 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
332 // At runtime initialize_itable is rerun as part of link_class_impl()
333 // for a shared class loaded by the non-boot loader to obtain the loader
334 // constraints based on the runtime classloaders' context. The dumptime
335 // itable index should be the same as the runtime index.
336 assert(_vtable_index == itable_index_max - index,
337 "archived itable index is different from runtime index");
338 return; // don’t write into the shared class
339 } else {
340 _vtable_index = itable_index_max - index;
341 }
342 assert(valid_itable_index(), "");
343 }
344
345
346
347 bool Method::was_executed_more_than(int n) {
348 // Invocation counter is reset when the Method* is compiled.
349 // If the method has compiled code we therefore assume it has
350 // be excuted more than n times.
351 if (is_accessor() || is_empty_method() || (code() != NULL)) {
352 // interpreter doesn't bump invocation counter of trivial methods
353 // compiler does not bump invocation counter of compiled methods
354 return true;
355 }
356 else if ((method_counters() != NULL &&
357 method_counters()->invocation_counter()->carry()) ||
358 (method_data() != NULL &&
359 method_data()->invocation_counter()->carry())) {
360 // The carry bit is set when the counter overflows and causes
361 // a compilation to occur. We don't know how many times
362 // the counter has been reset, so we simply assume it has
363 // been executed more than n times.
364 return true;
365 } else {
366 return invocation_count() > n;
367 }
368 }
369
370 void Method::print_invocation_count() {
371 if (is_static()) tty->print("static ");
372 if (is_final()) tty->print("final ");
373 if (is_synchronized()) tty->print("synchronized ");
374 if (is_native()) tty->print("native ");
375 tty->print("%s::", method_holder()->external_name());
376 name()->print_symbol_on(tty);
377 signature()->print_symbol_on(tty);
378
379 if (WizardMode) {
380 // dump the size of the byte codes
381 tty->print(" {%d}", code_size());
382 }
383 tty->cr();
384
385 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
386 tty->print_cr (" invocation_counter: %8d ", invocation_count());
387 tty->print_cr (" backedge_counter: %8d ", backedge_count());
388 #ifndef PRODUCT
389 if (CountCompiledCalls) {
390 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
391 }
392 #endif
393 }
394
395 // Build a MethodData* object to hold information about this method
396 // collected in the interpreter.
397 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
398 // Do not profile the method if metaspace has hit an OOM previously
399 // allocating profiling data. Callers clear pending exception so don't
400 // add one here.
401 if (ClassLoaderDataGraph::has_metaspace_oom()) {
402 return;
403 }
404
405 // Grab a lock here to prevent multiple
406 // MethodData*s from being created.
407 MutexLocker ml(MethodData_lock, THREAD);
408 if (method->method_data() == NULL) {
409 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
410 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
411 if (HAS_PENDING_EXCEPTION) {
412 CompileBroker::log_metaspace_failure();
413 ClassLoaderDataGraph::set_metaspace_oom(true);
414 return; // return the exception (which is cleared)
415 }
416
417 method->set_method_data(method_data);
418 if (PrintMethodData && (Verbose || WizardMode)) {
419 ResourceMark rm(THREAD);
420 tty->print("build_interpreter_method_data for ");
421 method->print_name(tty);
422 tty->cr();
423 // At the end of the run, the MDO, full of data, will be dumped.
424 }
425 }
426 }
427
428 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
429 // Do not profile the method if metaspace has hit an OOM previously
430 if (ClassLoaderDataGraph::has_metaspace_oom()) {
431 return NULL;
432 }
433
434 methodHandle mh(m);
435 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
436 if (HAS_PENDING_EXCEPTION) {
437 CompileBroker::log_metaspace_failure();
438 ClassLoaderDataGraph::set_metaspace_oom(true);
439 return NULL; // return the exception (which is cleared)
440 }
441 if (!mh->init_method_counters(counters)) {
442 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
443 }
444
445 if (LogTouchedMethods) {
446 mh->log_touched(CHECK_NULL);
447 }
448
449 return mh->method_counters();
450 }
451
452 void Method::cleanup_inline_caches() {
453 // The current system doesn't use inline caches in the interpreter
454 // => nothing to do (keep this method around for future use)
455 }
456
457
458 int Method::extra_stack_words() {
459 // not an inline function, to avoid a header dependency on Interpreter
460 return extra_stack_entries() * Interpreter::stackElementSize;
461 }
462
463
464 void Method::compute_size_of_parameters(Thread *thread) {
465 ArgumentSizeComputer asc(signature());
466 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
467 }
468
469 BasicType Method::result_type() const {
470 ResultTypeFinder rtf(signature());
471 return rtf.type();
472 }
473
474 #ifdef ASSERT
475 // ValueKlass the method is declared to return. This must not
476 // safepoint as it is called with references live on the stack at
477 // locations the GC is unaware of.
478 ValueKlass* Method::returned_value_type(Thread* thread) const {
479 assert(is_returning_vt(), "method return type should be value type");
480 SignatureStream ss(signature());
481 while (!ss.at_return_type()) {
482 ss.next();
483 }
484 Handle class_loader(thread, method_holder()->class_loader());
485 Handle protection_domain(thread, method_holder()->protection_domain());
486 Klass* k = NULL;
487 {
488 NoSafepointVerifier nsv;
489 k = ss.as_klass(class_loader, protection_domain, SignatureStream::ReturnNull, thread);
490 }
491 assert(k != NULL && !thread->has_pending_exception(), "can't resolve klass");
492 return ValueKlass::cast(k);
493 }
494 #endif
495
496 bool Method::is_empty_method() const {
497 return code_size() == 1
498 && *code_base() == Bytecodes::_return;
499 }
500
501
502 bool Method::is_vanilla_constructor() const {
503 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
504 // which only calls the superclass vanilla constructor and possibly does stores of
505 // zero constants to local fields:
506 //
507 // aload_0
508 // invokespecial
509 // indexbyte1
510 // indexbyte2
511 //
512 // followed by an (optional) sequence of:
513 //
514 // aload_0
515 // aconst_null / iconst_0 / fconst_0 / dconst_0
516 // putfield
517 // indexbyte1
518 // indexbyte2
519 //
520 // followed by:
521 //
522 // return
523
524 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
525 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
526 int size = code_size();
527 // Check if size match
528 if (size == 0 || size % 5 != 0) return false;
529 address cb = code_base();
530 int last = size - 1;
531 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
532 // Does not call superclass default constructor
533 return false;
534 }
535 // Check optional sequence
536 for (int i = 4; i < last; i += 5) {
537 if (cb[i] != Bytecodes::_aload_0) return false;
538 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
539 if (cb[i+2] != Bytecodes::_putfield) return false;
540 }
541 return true;
542 }
543
544
545 bool Method::compute_has_loops_flag() {
546 BytecodeStream bcs(this);
547 Bytecodes::Code bc;
548
549 while ((bc = bcs.next()) >= 0) {
550 switch( bc ) {
551 case Bytecodes::_ifeq:
552 case Bytecodes::_ifnull:
553 case Bytecodes::_iflt:
554 case Bytecodes::_ifle:
555 case Bytecodes::_ifne:
556 case Bytecodes::_ifnonnull:
557 case Bytecodes::_ifgt:
558 case Bytecodes::_ifge:
559 case Bytecodes::_if_icmpeq:
560 case Bytecodes::_if_icmpne:
561 case Bytecodes::_if_icmplt:
562 case Bytecodes::_if_icmpgt:
563 case Bytecodes::_if_icmple:
564 case Bytecodes::_if_icmpge:
565 case Bytecodes::_if_acmpeq:
566 case Bytecodes::_if_acmpne:
567 case Bytecodes::_goto:
568 case Bytecodes::_jsr:
569 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
570 break;
571
572 case Bytecodes::_goto_w:
573 case Bytecodes::_jsr_w:
574 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
575 break;
576 }
577 }
578 _access_flags.set_loops_flag_init();
579 return _access_flags.has_loops();
580 }
581
582 bool Method::is_final_method(AccessFlags class_access_flags) const {
583 // or "does_not_require_vtable_entry"
584 // default method or overpass can occur, is not final (reuses vtable entry)
585 // private methods in classes get vtable entries for backward class compatibility.
586 if (is_overpass() || is_default_method()) return false;
587 return is_final() || class_access_flags.is_final();
588 }
589
590 bool Method::is_final_method() const {
591 return is_final_method(method_holder()->access_flags());
592 }
593
594 bool Method::is_default_method() const {
595 if (method_holder() != NULL &&
596 method_holder()->is_interface() &&
597 !is_abstract() && !is_private()) {
598 return true;
599 } else {
600 return false;
601 }
602 }
603
604 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
605 if (is_final_method(class_access_flags)) return true;
606 #ifdef ASSERT
607 ResourceMark rm;
608 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
609 if (class_access_flags.is_interface()) {
610 assert(is_nonv == is_static() || is_nonv == is_private(),
611 "nonvirtual unexpected for non-static, non-private: %s",
612 name_and_sig_as_C_string());
613 }
614 #endif
615 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
616 return vtable_index() == nonvirtual_vtable_index;
617 }
618
619 bool Method::can_be_statically_bound() const {
620 return can_be_statically_bound(method_holder()->access_flags());
621 }
622
623 bool Method::is_accessor() const {
624 return is_getter() || is_setter();
625 }
626
627 bool Method::is_getter() const {
628 if (code_size() != 5) return false;
629 if (size_of_parameters() != 1) return false;
630 if (java_code_at(0) != Bytecodes::_aload_0) return false;
631 if (java_code_at(1) != Bytecodes::_getfield) return false;
632 switch (java_code_at(4)) {
633 case Bytecodes::_ireturn:
634 case Bytecodes::_lreturn:
635 case Bytecodes::_freturn:
636 case Bytecodes::_dreturn:
637 case Bytecodes::_areturn:
638 break;
639 default:
640 return false;
641 }
642 return true;
643 }
644
645 bool Method::is_setter() const {
646 if (code_size() != 6) return false;
647 if (java_code_at(0) != Bytecodes::_aload_0) return false;
648 switch (java_code_at(1)) {
649 case Bytecodes::_iload_1:
650 case Bytecodes::_aload_1:
651 case Bytecodes::_fload_1:
652 if (size_of_parameters() != 2) return false;
653 break;
654 case Bytecodes::_dload_1:
655 case Bytecodes::_lload_1:
656 if (size_of_parameters() != 3) return false;
657 break;
658 default:
659 return false;
660 }
661 if (java_code_at(2) != Bytecodes::_putfield) return false;
662 if (java_code_at(5) != Bytecodes::_return) return false;
663 return true;
664 }
665
666 bool Method::is_constant_getter() const {
667 int last_index = code_size() - 1;
668 // Check if the first 1-3 bytecodes are a constant push
669 // and the last bytecode is a return.
670 return (2 <= code_size() && code_size() <= 4 &&
671 Bytecodes::is_const(java_code_at(0)) &&
672 Bytecodes::length_for(java_code_at(0)) == last_index &&
673 Bytecodes::is_return(java_code_at(last_index)));
674 }
675
676 bool Method::is_initializer() const {
677 return is_object_initializer() || is_static_initializer();
678 }
679
680 bool Method::has_valid_initializer_flags() const {
681 return (is_static() ||
682 method_holder()->major_version() < 51);
683 }
684
685 bool Method::is_static_initializer() const {
686 // For classfiles version 51 or greater, ensure that the clinit method is
687 // static. Non-static methods with the name "<clinit>" are not static
688 // initializers. (older classfiles exempted for backward compatibility)
689 return name() == vmSymbols::class_initializer_name() &&
690 has_valid_initializer_flags();
691 }
692
693 bool Method::is_object_initializer() const {
694 return name() == vmSymbols::object_initializer_name();
695 }
696
697 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
698 int length = method->checked_exceptions_length();
699 if (length == 0) { // common case
700 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
701 } else {
702 methodHandle h_this(THREAD, method);
703 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
704 objArrayHandle mirrors (THREAD, m_oop);
705 for (int i = 0; i < length; i++) {
706 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
707 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
708 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
709 mirrors->obj_at_put(i, k->java_mirror());
710 }
711 return mirrors;
712 }
713 };
714
715
716 int Method::line_number_from_bci(int bci) const {
717 if (bci == SynchronizationEntryBCI) bci = 0;
718 assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
719 int best_bci = 0;
720 int best_line = -1;
721
722 if (has_linenumber_table()) {
723 // The line numbers are a short array of 2-tuples [start_pc, line_number].
724 // Not necessarily sorted and not necessarily one-to-one.
725 CompressedLineNumberReadStream stream(compressed_linenumber_table());
726 while (stream.read_pair()) {
727 if (stream.bci() == bci) {
728 // perfect match
729 return stream.line();
730 } else {
731 // update best_bci/line
732 if (stream.bci() < bci && stream.bci() >= best_bci) {
733 best_bci = stream.bci();
734 best_line = stream.line();
735 }
736 }
737 }
738 }
739 return best_line;
740 }
741
742
743 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
744 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
745 Thread *thread = Thread::current();
746 Symbol* klass_name = constants()->klass_name_at(klass_index);
747 Handle loader(thread, method_holder()->class_loader());
748 Handle prot (thread, method_holder()->protection_domain());
749 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
750 } else {
751 return true;
752 }
753 }
754
755
756 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
757 int klass_index = constants()->klass_ref_index_at(refinfo_index);
758 if (must_be_resolved) {
759 // Make sure klass is resolved in constantpool.
760 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
761 }
762 return is_klass_loaded_by_klass_index(klass_index);
763 }
764
765
766 void Method::set_native_function(address function, bool post_event_flag) {
767 assert(function != NULL, "use clear_native_function to unregister natives");
768 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
769 address* native_function = native_function_addr();
770
771 // We can see racers trying to place the same native function into place. Once
772 // is plenty.
773 address current = *native_function;
774 if (current == function) return;
775 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
776 function != NULL) {
777 // native_method_throw_unsatisfied_link_error_entry() should only
778 // be passed when post_event_flag is false.
779 assert(function !=
780 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
781 "post_event_flag mis-match");
782
783 // post the bind event, and possible change the bind function
784 JvmtiExport::post_native_method_bind(this, &function);
785 }
786 *native_function = function;
787 // This function can be called more than once. We must make sure that we always
788 // use the latest registered method -> check if a stub already has been generated.
789 // If so, we have to make it not_entrant.
790 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
791 if (nm != NULL) {
792 nm->make_not_entrant();
793 }
794 }
795
796
797 bool Method::has_native_function() const {
798 if (is_method_handle_intrinsic())
799 return false; // special-cased in SharedRuntime::generate_native_wrapper
800 address func = native_function();
801 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
802 }
803
804
805 void Method::clear_native_function() {
806 // Note: is_method_handle_intrinsic() is allowed here.
807 set_native_function(
808 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
809 !native_bind_event_is_interesting);
810 clear_code();
811 }
812
813 address Method::critical_native_function() {
814 methodHandle mh(this);
815 return NativeLookup::lookup_critical_entry(mh);
816 }
817
818
819 void Method::set_signature_handler(address handler) {
820 address* signature_handler = signature_handler_addr();
821 *signature_handler = handler;
822 }
823
824
825 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
826 if (PrintCompilation && report) {
827 ttyLocker ttyl;
828 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
829 if (comp_level == CompLevel_all) {
830 tty->print("all levels ");
831 } else {
832 tty->print("levels ");
833 for (int i = (int)CompLevel_none; i <= comp_level; i++) {
834 tty->print("%d ", i);
835 }
836 }
837 this->print_short_name(tty);
838 int size = this->code_size();
839 if (size > 0) {
840 tty->print(" (%d bytes)", size);
841 }
842 if (reason != NULL) {
843 tty->print(" %s", reason);
844 }
845 tty->cr();
846 }
847 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
848 ttyLocker ttyl;
849 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
850 os::current_thread_id(), is_osr, comp_level);
851 if (reason != NULL) {
852 xtty->print(" reason=\'%s\'", reason);
853 }
854 xtty->method(this);
855 xtty->stamp();
856 xtty->end_elem();
857 }
858 }
859
860 bool Method::is_always_compilable() const {
861 // Generated adapters must be compiled
862 if (is_method_handle_intrinsic() && is_synthetic()) {
863 assert(!is_not_c1_compilable(), "sanity check");
864 assert(!is_not_c2_compilable(), "sanity check");
865 return true;
866 }
867
868 return false;
869 }
870
871 bool Method::is_not_compilable(int comp_level) const {
872 if (number_of_breakpoints() > 0)
873 return true;
874 if (is_always_compilable())
875 return false;
876 if (comp_level == CompLevel_any)
877 return is_not_c1_compilable() || is_not_c2_compilable();
878 if (is_c1_compile(comp_level))
879 return is_not_c1_compilable();
880 if (is_c2_compile(comp_level))
881 return is_not_c2_compilable();
882 return false;
883 }
884
885 // call this when compiler finds that this method is not compilable
886 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
887 if (is_always_compilable()) {
888 // Don't mark a method which should be always compilable
889 return;
890 }
891 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
892 if (comp_level == CompLevel_all) {
893 set_not_c1_compilable();
894 set_not_c2_compilable();
895 } else {
896 if (is_c1_compile(comp_level))
897 set_not_c1_compilable();
898 if (is_c2_compile(comp_level))
899 set_not_c2_compilable();
900 }
901 CompilationPolicy::policy()->disable_compilation(this);
902 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
903 }
904
905 bool Method::is_not_osr_compilable(int comp_level) const {
906 if (is_not_compilable(comp_level))
907 return true;
908 if (comp_level == CompLevel_any)
909 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
910 if (is_c1_compile(comp_level))
911 return is_not_c1_osr_compilable();
912 if (is_c2_compile(comp_level))
913 return is_not_c2_osr_compilable();
914 return false;
915 }
916
917 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
918 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
919 if (comp_level == CompLevel_all) {
920 set_not_c1_osr_compilable();
921 set_not_c2_osr_compilable();
922 } else {
923 if (is_c1_compile(comp_level))
924 set_not_c1_osr_compilable();
925 if (is_c2_compile(comp_level))
926 set_not_c2_osr_compilable();
927 }
928 CompilationPolicy::policy()->disable_compilation(this);
929 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
930 }
931
932 // Revert to using the interpreter and clear out the nmethod
933 void Method::clear_code(bool acquire_lock /* = true */) {
934 MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
935 // this may be NULL if c2i adapters have not been made yet
936 // Only should happen at allocate time.
937 if (adapter() == NULL) {
938 _from_compiled_entry = NULL;
939 } else {
940 _from_compiled_entry = adapter()->get_c2i_entry();
941 }
942 OrderAccess::storestore();
943 _from_interpreted_entry = _i2i_entry;
944 OrderAccess::storestore();
945 _code = NULL;
946 }
947
948 #if INCLUDE_CDS
949 // Called by class data sharing to remove any entry points (which are not shared)
950 void Method::unlink_method() {
951 _code = NULL;
952
953 assert(DumpSharedSpaces, "dump time only");
954 // Set the values to what they should be at run time. Note that
955 // this Method can no longer be executed during dump time.
956 _i2i_entry = Interpreter::entry_for_cds_method(this);
957 _from_interpreted_entry = _i2i_entry;
958
959 if (is_native()) {
960 *native_function_addr() = NULL;
961 set_signature_handler(NULL);
962 }
963 NOT_PRODUCT(set_compiled_invocation_count(0);)
964
965 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
966 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
967 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
968 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
969
970
971 // In case of DumpSharedSpaces, _method_data should always be NULL.
972 assert(_method_data == NULL, "unexpected method data?");
973
974 set_method_data(NULL);
975 clear_method_counters();
976 }
977 #endif
978
979 /****************************************************************************
980 // The following illustrates how the entries work for CDS shared Methods:
981 //
982 // Our goal is to delay writing into a shared Method until it's compiled.
983 // Hence, we want to determine the initial values for _i2i_entry,
984 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
985 //
986 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
987 // They also have similar signatures so that they will share the same
988 // AdapterHandlerEntry.
989 //
990 // _adapter_trampoline points to a fixed location in the RW section of
991 // the CDS archive. This location initially contains a NULL pointer. When the
992 // first of method A or B is linked, an AdapterHandlerEntry is allocated
993 // dynamically, and its c2i/i2c entries are generated.
994 //
995 // _i2i_entry and _from_interpreted_entry initially points to the same
996 // (fixed) location in the CODE section of the CDS archive. This contains
997 // an unconditional branch to the actual entry for "zero_locals", which is
998 // generated at run time and may be on an arbitrary address. Thus, the
999 // unconditional branch is also generated at run time to jump to the correct
1000 // address.
1001 //
1002 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1003 // section. This address has enough space for an unconditional branch
1004 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1005 // initialized, and the address for the actual c2i_entry is known, we emit a
1006 // branch instruction here to branch to the actual c2i_entry.
1007 //
1008 // The effect of the extra branch on the i2i and c2i entries is negligible.
1009 //
1010 // The reason for putting _adapter_trampoline in RO is many shared Methods
1011 // share the same AdapterHandlerEntry, so we can save space in the RW section
1012 // by having the extra indirection.
1013
1014
1015 [Method A: RW]
1016 _constMethod ----> [ConstMethod: RO]
1017 _adapter_trampoline -----------+
1018 |
1019 _i2i_entry (same value as method B) |
1020 _from_interpreted_entry (same value as method B) |
1021 _from_compiled_entry (same value as method B) |
1022 |
1023 |
1024 [Method B: RW] +--------+
1025 _constMethod ----> [ConstMethod: RO] |
1026 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1027 |
1028 +-------------------------------+
1029 |
1030 +----> [AdapterHandlerEntry] (allocated at run time)
1031 _fingerprint
1032 _c2i_entry ---------------------------------+->[c2i entry..]
1033 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1034 _from_interpreted_entry | _c2i_unverified_entry | |
1035 | | | |
1036 | | (_cds_entry_table: CODE) | |
1037 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1038 | | (allocated at run time) | |
1039 | | ... [asm code ...] | |
1040 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1041 | | |
1042 | | |
1043 +-[compiled]-------------------------------------------------------------------+ |
1044 |
1045 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1046 [jmp c2i_entry] ------------------------------------------------------+
1047
1048 ***/
1049
1050 // Called when the method_holder is getting linked. Setup entrypoints so the method
1051 // is ready to be called from interpreter, compiler, and vtables.
1052 void Method::link_method(const methodHandle& h_method, TRAPS) {
1053 // If the code cache is full, we may reenter this function for the
1054 // leftover methods that weren't linked.
1055 if (is_shared()) {
1056 address entry = Interpreter::entry_for_cds_method(h_method);
1057 assert(entry != NULL && entry == _i2i_entry,
1058 "should be correctly set during dump time");
1059 if (adapter() != NULL) {
1060 return;
1061 }
1062 assert(entry == _from_interpreted_entry,
1063 "should be correctly set during dump time");
1064 } else if (_i2i_entry != NULL) {
1065 return;
1066 }
1067 assert( _code == NULL, "nothing compiled yet" );
1068
1069 // Setup interpreter entrypoint
1070 assert(this == h_method(), "wrong h_method()" );
1071
1072 if (!is_shared()) {
1073 assert(adapter() == NULL, "init'd to NULL");
1074 address entry = Interpreter::entry_for_method(h_method);
1075 assert(entry != NULL, "interpreter entry must be non-null");
1076 // Sets both _i2i_entry and _from_interpreted_entry
1077 set_interpreter_entry(entry);
1078 }
1079
1080 // Don't overwrite already registered native entries.
1081 if (is_native() && !has_native_function()) {
1082 set_native_function(
1083 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1084 !native_bind_event_is_interesting);
1085 }
1086
1087 // Setup compiler entrypoint. This is made eagerly, so we do not need
1088 // special handling of vtables. An alternative is to make adapters more
1089 // lazily by calling make_adapter() from from_compiled_entry() for the
1090 // normal calls. For vtable calls life gets more complicated. When a
1091 // call-site goes mega-morphic we need adapters in all methods which can be
1092 // called from the vtable. We need adapters on such methods that get loaded
1093 // later. Ditto for mega-morphic itable calls. If this proves to be a
1094 // problem we'll make these lazily later.
1095 (void) make_adapters(h_method, CHECK);
1096
1097 // ONLY USE the h_method now as make_adapter may have blocked
1098
1099 }
1100
1101 address Method::make_adapters(methodHandle mh, TRAPS) {
1102 // Adapters for compiled code are made eagerly here. They are fairly
1103 // small (generally < 100 bytes) and quick to make (and cached and shared)
1104 // so making them eagerly shouldn't be too expensive.
1105 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1106 if (adapter == NULL ) {
1107 if (!is_init_completed()) {
1108 // Don't throw exceptions during VM initialization because java.lang.* classes
1109 // might not have been initialized, causing problems when constructing the
1110 // Java exception object.
1111 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1112 } else {
1113 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1114 }
1115 }
1116
1117 if (mh->is_shared()) {
1118 assert(mh->adapter() == adapter, "must be");
1119 assert(mh->_from_compiled_entry != NULL, "must be");
1120 } else {
1121 mh->set_adapter_entry(adapter);
1122 mh->_from_compiled_entry = adapter->get_c2i_entry();
1123 }
1124 return adapter->get_c2i_entry();
1125 }
1126
1127 void Method::restore_unshareable_info(TRAPS) {
1128 assert(is_method() && is_valid_method(), "ensure C++ vtable is restored");
1129
1130 // Since restore_unshareable_info can be called more than once for a method, don't
1131 // redo any work.
1132 if (adapter() == NULL) {
1133 methodHandle mh(THREAD, this);
1134 link_method(mh, CHECK);
1135 }
1136 }
1137
1138 volatile address Method::from_compiled_entry_no_trampoline() const {
1139 nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
1140 if (code) {
1141 return code->verified_entry_point();
1142 } else {
1143 return adapter()->get_c2i_entry();
1144 }
1145 }
1146
1147 // The verified_code_entry() must be called when a invoke is resolved
1148 // on this method.
1149
1150 // It returns the compiled code entry point, after asserting not null.
1151 // This function is called after potential safepoints so that nmethod
1152 // or adapter that it points to is still live and valid.
1153 // This function must not hit a safepoint!
1154 address Method::verified_code_entry() {
1155 debug_only(NoSafepointVerifier nsv;)
1156 assert(_from_compiled_entry != NULL, "must be set");
1157 return _from_compiled_entry;
1158 }
1159
1160 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1161 // (could be racing a deopt).
1162 // Not inline to avoid circular ref.
1163 bool Method::check_code() const {
1164 // cached in a register or local. There's a race on the value of the field.
1165 CompiledMethod *code = (CompiledMethod *)OrderAccess::load_ptr_acquire(&_code);
1166 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1167 }
1168
1169 // Install compiled code. Instantly it can execute.
1170 void Method::set_code(methodHandle mh, CompiledMethod *code) {
1171 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1172 assert( code, "use clear_code to remove code" );
1173 assert( mh->check_code(), "" );
1174
1175 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1176
1177 // These writes must happen in this order, because the interpreter will
1178 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1179 // which jumps to _from_compiled_entry.
1180 mh->_code = code; // Assign before allowing compiled code to exec
1181
1182 int comp_level = code->comp_level();
1183 // In theory there could be a race here. In practice it is unlikely
1184 // and not worth worrying about.
1185 if (comp_level > mh->highest_comp_level()) {
1186 mh->set_highest_comp_level(comp_level);
1187 }
1188
1189 OrderAccess::storestore();
1190 #ifdef SHARK
1191 mh->_from_interpreted_entry = code->insts_begin();
1192 #else //!SHARK
1193 mh->_from_compiled_entry = code->verified_entry_point();
1194 OrderAccess::storestore();
1195 // Instantly compiled code can execute.
1196 if (!mh->is_method_handle_intrinsic())
1197 mh->_from_interpreted_entry = mh->get_i2c_entry();
1198 #endif //!SHARK
1199 }
1200
1201
1202 bool Method::is_overridden_in(Klass* k) const {
1203 InstanceKlass* ik = InstanceKlass::cast(k);
1204
1205 if (ik->is_interface()) return false;
1206
1207 // If method is an interface, we skip it - except if it
1208 // is a miranda method
1209 if (method_holder()->is_interface()) {
1210 // Check that method is not a miranda method
1211 if (ik->lookup_method(name(), signature()) == NULL) {
1212 // No implementation exist - so miranda method
1213 return false;
1214 }
1215 return true;
1216 }
1217
1218 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1219 if (!has_vtable_index()) {
1220 return false;
1221 } else {
1222 Method* vt_m = ik->method_at_vtable(vtable_index());
1223 return vt_m != this;
1224 }
1225 }
1226
1227
1228 // give advice about whether this Method* should be cached or not
1229 bool Method::should_not_be_cached() const {
1230 if (is_old()) {
1231 // This method has been redefined. It is either EMCP or obsolete
1232 // and we don't want to cache it because that would pin the method
1233 // down and prevent it from being collectible if and when it
1234 // finishes executing.
1235 return true;
1236 }
1237
1238 // caching this method should be just fine
1239 return false;
1240 }
1241
1242
1243 /**
1244 * Returns true if this is one of the specially treated methods for
1245 * security related stack walks (like Reflection.getCallerClass).
1246 */
1247 bool Method::is_ignored_by_security_stack_walk() const {
1248 if (intrinsic_id() == vmIntrinsics::_invoke) {
1249 // This is Method.invoke() -- ignore it
1250 return true;
1251 }
1252 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1253 // This is an auxilary frame -- ignore it
1254 return true;
1255 }
1256 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1257 // This is an internal adapter frame for method handles -- ignore it
1258 return true;
1259 }
1260 return false;
1261 }
1262
1263
1264 // Constant pool structure for invoke methods:
1265 enum {
1266 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1267 _imcp_invoke_signature, // utf8: (variable Symbol*)
1268 _imcp_limit
1269 };
1270
1271 // Test if this method is an MH adapter frame generated by Java code.
1272 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1273 bool Method::is_compiled_lambda_form() const {
1274 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1275 }
1276
1277 // Test if this method is an internal MH primitive method.
1278 bool Method::is_method_handle_intrinsic() const {
1279 vmIntrinsics::ID iid = intrinsic_id();
1280 return (MethodHandles::is_signature_polymorphic(iid) &&
1281 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1282 }
1283
1284 bool Method::has_member_arg() const {
1285 vmIntrinsics::ID iid = intrinsic_id();
1286 return (MethodHandles::is_signature_polymorphic(iid) &&
1287 MethodHandles::has_member_arg(iid));
1288 }
1289
1290 // Make an instance of a signature-polymorphic internal MH primitive.
1291 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1292 Symbol* signature,
1293 TRAPS) {
1294 ResourceMark rm;
1295 methodHandle empty;
1296
1297 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1298 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1299 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1300 if (TraceMethodHandles) {
1301 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1302 }
1303
1304 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1305 name->increment_refcount();
1306 signature->increment_refcount();
1307
1308 int cp_length = _imcp_limit;
1309 ClassLoaderData* loader_data = holder->class_loader_data();
1310 constantPoolHandle cp;
1311 {
1312 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1313 cp = constantPoolHandle(THREAD, cp_oop);
1314 }
1315 cp->set_pool_holder(holder);
1316 cp->symbol_at_put(_imcp_invoke_name, name);
1317 cp->symbol_at_put(_imcp_invoke_signature, signature);
1318 cp->set_has_preresolution();
1319
1320 // decide on access bits: public or not?
1321 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1322 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1323 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1324 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1325
1326 methodHandle m;
1327 {
1328 InlineTableSizes sizes;
1329 Method* m_oop = Method::allocate(loader_data, 0,
1330 accessFlags_from(flags_bits), &sizes,
1331 ConstMethod::NORMAL, CHECK_(empty));
1332 m = methodHandle(THREAD, m_oop);
1333 }
1334 m->set_constants(cp());
1335 m->set_name_index(_imcp_invoke_name);
1336 m->set_signature_index(_imcp_invoke_signature);
1337 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1338 assert(m->signature() == signature, "");
1339 ResultTypeFinder rtf(signature);
1340 m->constMethod()->set_result_type(rtf.type());
1341 m->compute_size_of_parameters(THREAD);
1342 m->init_intrinsic_id();
1343 assert(m->is_method_handle_intrinsic(), "");
1344 #ifdef ASSERT
1345 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1346 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1347 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1348 #endif //ASSERT
1349
1350 // Finally, set up its entry points.
1351 assert(m->can_be_statically_bound(), "");
1352 m->set_vtable_index(Method::nonvirtual_vtable_index);
1353 m->link_method(m, CHECK_(empty));
1354
1355 if (TraceMethodHandles && (Verbose || WizardMode)) {
1356 ttyLocker ttyl;
1357 m->print_on(tty);
1358 }
1359
1360 return m;
1361 }
1362
1363 Klass* Method::check_non_bcp_klass(Klass* klass) {
1364 if (klass != NULL && klass->class_loader() != NULL) {
1365 if (klass->is_objArray_klass())
1366 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1367 return klass;
1368 }
1369 return NULL;
1370 }
1371
1372
1373 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1374 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1375 // Code below does not work for native methods - they should never get rewritten anyway
1376 assert(!m->is_native(), "cannot rewrite native methods");
1377 // Allocate new Method*
1378 AccessFlags flags = m->access_flags();
1379
1380 ConstMethod* cm = m->constMethod();
1381 int checked_exceptions_len = cm->checked_exceptions_length();
1382 int localvariable_len = cm->localvariable_table_length();
1383 int exception_table_len = cm->exception_table_length();
1384 int method_parameters_len = cm->method_parameters_length();
1385 int method_annotations_len = cm->method_annotations_length();
1386 int parameter_annotations_len = cm->parameter_annotations_length();
1387 int type_annotations_len = cm->type_annotations_length();
1388 int default_annotations_len = cm->default_annotations_length();
1389
1390 InlineTableSizes sizes(
1391 localvariable_len,
1392 new_compressed_linenumber_size,
1393 exception_table_len,
1394 checked_exceptions_len,
1395 method_parameters_len,
1396 cm->generic_signature_index(),
1397 method_annotations_len,
1398 parameter_annotations_len,
1399 type_annotations_len,
1400 default_annotations_len,
1401 0);
1402
1403 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1404 Method* newm_oop = Method::allocate(loader_data,
1405 new_code_length,
1406 flags,
1407 &sizes,
1408 m->method_type(),
1409 CHECK_(methodHandle()));
1410 methodHandle newm (THREAD, newm_oop);
1411
1412 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1413 ConstMethod* newcm = newm->constMethod();
1414 int new_const_method_size = newm->constMethod()->size();
1415
1416 memcpy(newm(), m(), sizeof(Method));
1417
1418 // Create shallow copy of ConstMethod.
1419 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1420
1421 // Reset correct method/const method, method size, and parameter info
1422 newm->set_constMethod(newcm);
1423 newm->constMethod()->set_code_size(new_code_length);
1424 newm->constMethod()->set_constMethod_size(new_const_method_size);
1425 assert(newm->code_size() == new_code_length, "check");
1426 assert(newm->method_parameters_length() == method_parameters_len, "check");
1427 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1428 assert(newm->exception_table_length() == exception_table_len, "check");
1429 assert(newm->localvariable_table_length() == localvariable_len, "check");
1430 // Copy new byte codes
1431 memcpy(newm->code_base(), new_code, new_code_length);
1432 // Copy line number table
1433 if (new_compressed_linenumber_size > 0) {
1434 memcpy(newm->compressed_linenumber_table(),
1435 new_compressed_linenumber_table,
1436 new_compressed_linenumber_size);
1437 }
1438 // Copy method_parameters
1439 if (method_parameters_len > 0) {
1440 memcpy(newm->method_parameters_start(),
1441 m->method_parameters_start(),
1442 method_parameters_len * sizeof(MethodParametersElement));
1443 }
1444 // Copy checked_exceptions
1445 if (checked_exceptions_len > 0) {
1446 memcpy(newm->checked_exceptions_start(),
1447 m->checked_exceptions_start(),
1448 checked_exceptions_len * sizeof(CheckedExceptionElement));
1449 }
1450 // Copy exception table
1451 if (exception_table_len > 0) {
1452 memcpy(newm->exception_table_start(),
1453 m->exception_table_start(),
1454 exception_table_len * sizeof(ExceptionTableElement));
1455 }
1456 // Copy local variable number table
1457 if (localvariable_len > 0) {
1458 memcpy(newm->localvariable_table_start(),
1459 m->localvariable_table_start(),
1460 localvariable_len * sizeof(LocalVariableTableElement));
1461 }
1462 // Copy stackmap table
1463 if (m->has_stackmap_table()) {
1464 int code_attribute_length = m->stackmap_data()->length();
1465 Array<u1>* stackmap_data =
1466 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1467 memcpy((void*)stackmap_data->adr_at(0),
1468 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1469 newm->set_stackmap_data(stackmap_data);
1470 }
1471
1472 // copy annotations over to new method
1473 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1474 return newm;
1475 }
1476
1477 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1478 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1479 // because we are not loading from core libraries
1480 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1481 // which does not use the class default class loader so we check for its loader here
1482 const InstanceKlass* ik = InstanceKlass::cast(holder);
1483 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1484 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1485 }
1486
1487 // see if the klass name is well-known:
1488 Symbol* klass_name = ik->name();
1489 return vmSymbols::find_sid(klass_name);
1490 }
1491
1492 void Method::init_intrinsic_id() {
1493 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1494 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1495 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1496 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1497
1498 // the klass name is well-known:
1499 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1500 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1501
1502 // ditto for method and signature:
1503 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1504 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1505 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1506 && name_id == vmSymbols::NO_SID) {
1507 return;
1508 }
1509 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1510 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1511 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1512 && sig_id == vmSymbols::NO_SID) {
1513 return;
1514 }
1515 jshort flags = access_flags().as_short();
1516
1517 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1518 if (id != vmIntrinsics::_none) {
1519 set_intrinsic_id(id);
1520 if (id == vmIntrinsics::_Class_cast) {
1521 // Even if the intrinsic is rejected, we want to inline this simple method.
1522 set_force_inline(true);
1523 }
1524 return;
1525 }
1526
1527 // A few slightly irregular cases:
1528 switch (klass_id) {
1529 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1530 // Second chance: check in regular Math.
1531 switch (name_id) {
1532 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1533 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1534 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1535 // pretend it is the corresponding method in the non-strict class:
1536 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1537 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1538 break;
1539 }
1540 break;
1541
1542 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1543 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1544 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1545 if (!is_native()) break;
1546 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1547 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1548 id = vmIntrinsics::_none;
1549 break;
1550 }
1551
1552 if (id != vmIntrinsics::_none) {
1553 // Set up its iid. It is an alias method.
1554 set_intrinsic_id(id);
1555 return;
1556 }
1557 }
1558
1559 // These two methods are static since a GC may move the Method
1560 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1561 if (!THREAD->can_call_java()) {
1562 // There is nothing useful this routine can do from within the Compile thread.
1563 // Hopefully, the signature contains only well-known classes.
1564 // We could scan for this and return true/false, but the caller won't care.
1565 return false;
1566 }
1567 bool sig_is_loaded = true;
1568 Handle class_loader(THREAD, m->method_holder()->class_loader());
1569 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1570 ResourceMark rm(THREAD);
1571 Symbol* signature = m->signature();
1572 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1573 if (ss.is_object()) {
1574 Symbol* sym = ss.as_symbol(CHECK_(false));
1575 Symbol* name = sym;
1576 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1577 protection_domain, THREAD);
1578 // We are loading classes eagerly. If a ClassNotFoundException or
1579 // a LinkageError was generated, be sure to ignore it.
1580 if (HAS_PENDING_EXCEPTION) {
1581 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1582 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1583 CLEAR_PENDING_EXCEPTION;
1584 } else {
1585 return false;
1586 }
1587 }
1588 if( klass == NULL) { sig_is_loaded = false; }
1589 }
1590 }
1591 return sig_is_loaded;
1592 }
1593
1594 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1595 Handle class_loader(THREAD, m->method_holder()->class_loader());
1596 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1597 ResourceMark rm(THREAD);
1598 Symbol* signature = m->signature();
1599 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1600 if (ss.type() == T_OBJECT) {
1601 Symbol* name = ss.as_symbol_or_null();
1602 if (name == NULL) return true;
1603 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1604 if (klass == NULL) return true;
1605 }
1606 }
1607 return false;
1608 }
1609
1610 // Exposed so field engineers can debug VM
1611 void Method::print_short_name(outputStream* st) {
1612 ResourceMark rm;
1613 #ifdef PRODUCT
1614 st->print(" %s::", method_holder()->external_name());
1615 #else
1616 st->print(" %s::", method_holder()->internal_name());
1617 #endif
1618 name()->print_symbol_on(st);
1619 if (WizardMode) signature()->print_symbol_on(st);
1620 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1621 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1622 }
1623
1624 // Comparer for sorting an object array containing
1625 // Method*s.
1626 static int method_comparator(Method* a, Method* b) {
1627 return a->name()->fast_compare(b->name());
1628 }
1629
1630 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1631 // default_methods also uses this without the ordering for fast find_method
1632 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1633 int length = methods->length();
1634 if (length > 1) {
1635 {
1636 NoSafepointVerifier nsv;
1637 QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1638 }
1639 // Reset method ordering
1640 if (set_idnums) {
1641 for (int i = 0; i < length; i++) {
1642 Method* m = methods->at(i);
1643 m->set_method_idnum(i);
1644 m->set_orig_method_idnum(i);
1645 }
1646 }
1647 }
1648 }
1649
1650 //-----------------------------------------------------------------------------------
1651 // Non-product code unless JVM/TI needs it
1652
1653 #if !defined(PRODUCT) || INCLUDE_JVMTI
1654 class SignatureTypePrinter : public SignatureTypeNames {
1655 private:
1656 outputStream* _st;
1657 bool _use_separator;
1658
1659 void type_name(const char* name) {
1660 if (_use_separator) _st->print(", ");
1661 _st->print("%s", name);
1662 _use_separator = true;
1663 }
1664
1665 public:
1666 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1667 _st = st;
1668 _use_separator = false;
1669 }
1670
1671 void print_parameters() { _use_separator = false; iterate_parameters(); }
1672 void print_returntype() { _use_separator = false; iterate_returntype(); }
1673 };
1674
1675
1676 void Method::print_name(outputStream* st) {
1677 Thread *thread = Thread::current();
1678 ResourceMark rm(thread);
1679 st->print("%s ", is_static() ? "static" : "virtual");
1680 if (WizardMode) {
1681 st->print("%s.", method_holder()->internal_name());
1682 name()->print_symbol_on(st);
1683 signature()->print_symbol_on(st);
1684 } else {
1685 SignatureTypePrinter sig(signature(), st);
1686 sig.print_returntype();
1687 st->print(" %s.", method_holder()->internal_name());
1688 name()->print_symbol_on(st);
1689 st->print("(");
1690 sig.print_parameters();
1691 st->print(")");
1692 }
1693 }
1694 #endif // !PRODUCT || INCLUDE_JVMTI
1695
1696
1697 void Method::print_codes_on(outputStream* st) const {
1698 print_codes_on(0, code_size(), st);
1699 }
1700
1701 void Method::print_codes_on(int from, int to, outputStream* st) const {
1702 Thread *thread = Thread::current();
1703 ResourceMark rm(thread);
1704 methodHandle mh (thread, (Method*)this);
1705 BytecodeStream s(mh);
1706 s.set_interval(from, to);
1707 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1708 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1709 }
1710
1711
1712 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1713 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1714 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1715 // as end-of-stream terminator.
1716
1717 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1718 // bci and line number does not compress into single byte.
1719 // Write out escape character and use regular compression for bci and line number.
1720 write_byte((jubyte)0xFF);
1721 write_signed_int(bci_delta);
1722 write_signed_int(line_delta);
1723 }
1724
1725 // See comment in method.hpp which explains why this exists.
1726 #if defined(_M_AMD64) && _MSC_VER >= 1400
1727 #pragma optimize("", off)
1728 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1729 write_pair_inline(bci, line);
1730 }
1731 #pragma optimize("", on)
1732 #endif
1733
1734 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1735 _bci = 0;
1736 _line = 0;
1737 };
1738
1739
1740 bool CompressedLineNumberReadStream::read_pair() {
1741 jubyte next = read_byte();
1742 // Check for terminator
1743 if (next == 0) return false;
1744 if (next == 0xFF) {
1745 // Escape character, regular compression used
1746 _bci += read_signed_int();
1747 _line += read_signed_int();
1748 } else {
1749 // Single byte compression used
1750 _bci += next >> 3;
1751 _line += next & 0x7;
1752 }
1753 return true;
1754 }
1755
1756 #if INCLUDE_JVMTI
1757
1758 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1759 BreakpointInfo* bp = method_holder()->breakpoints();
1760 for (; bp != NULL; bp = bp->next()) {
1761 if (bp->match(this, bci)) {
1762 return bp->orig_bytecode();
1763 }
1764 }
1765 {
1766 ResourceMark rm;
1767 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1768 }
1769 return Bytecodes::_shouldnotreachhere;
1770 }
1771
1772 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1773 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1774 BreakpointInfo* bp = method_holder()->breakpoints();
1775 for (; bp != NULL; bp = bp->next()) {
1776 if (bp->match(this, bci)) {
1777 bp->set_orig_bytecode(code);
1778 // and continue, in case there is more than one
1779 }
1780 }
1781 }
1782
1783 void Method::set_breakpoint(int bci) {
1784 InstanceKlass* ik = method_holder();
1785 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1786 bp->set_next(ik->breakpoints());
1787 ik->set_breakpoints(bp);
1788 // do this last:
1789 bp->set(this);
1790 }
1791
1792 static void clear_matches(Method* m, int bci) {
1793 InstanceKlass* ik = m->method_holder();
1794 BreakpointInfo* prev_bp = NULL;
1795 BreakpointInfo* next_bp;
1796 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1797 next_bp = bp->next();
1798 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1799 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1800 // do this first:
1801 bp->clear(m);
1802 // unhook it
1803 if (prev_bp != NULL)
1804 prev_bp->set_next(next_bp);
1805 else
1806 ik->set_breakpoints(next_bp);
1807 delete bp;
1808 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1809 // at same location. So we have multiple matching (method_index and bci)
1810 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1811 // breakpoint for clear_breakpoint request and keep all other method versions
1812 // BreakpointInfo for future clear_breakpoint request.
1813 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1814 // which is being called when class is unloaded. We delete all the Breakpoint
1815 // information for all versions of method. We may not correctly restore the original
1816 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1817 // so these methods won't be used anymore.
1818 if (bci >= 0) {
1819 break;
1820 }
1821 } else {
1822 // This one is a keeper.
1823 prev_bp = bp;
1824 }
1825 }
1826 }
1827
1828 void Method::clear_breakpoint(int bci) {
1829 assert(bci >= 0, "");
1830 clear_matches(this, bci);
1831 }
1832
1833 void Method::clear_all_breakpoints() {
1834 clear_matches(this, -1);
1835 }
1836
1837 #endif // INCLUDE_JVMTI
1838
1839 int Method::invocation_count() {
1840 MethodCounters *mcs = method_counters();
1841 if (TieredCompilation) {
1842 MethodData* const mdo = method_data();
1843 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1844 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1845 return InvocationCounter::count_limit;
1846 } else {
1847 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1848 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1849 }
1850 } else {
1851 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1852 }
1853 }
1854
1855 int Method::backedge_count() {
1856 MethodCounters *mcs = method_counters();
1857 if (TieredCompilation) {
1858 MethodData* const mdo = method_data();
1859 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1860 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1861 return InvocationCounter::count_limit;
1862 } else {
1863 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1864 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1865 }
1866 } else {
1867 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1868 }
1869 }
1870
1871 void Method::initialize_max_vt_buffer() {
1872 long long max_entries = constMethod()->max_locals() + constMethod()->max_stack();
1873 max_entries *= 2; // Add margin for loops
1874 long long max_size = max_entries * (BigValueTypeThreshold + 8); // 8 -> header size
1875 int max_chunks = (int)(max_size / VTBufferChunk::max_alloc_size()) + 1;
1876 set_max_vt_buffer(MAX2(MinimumVTBufferChunkPerFrame, max_chunks));
1877 }
1878
1879 int Method::highest_comp_level() const {
1880 const MethodCounters* mcs = method_counters();
1881 if (mcs != NULL) {
1882 return mcs->highest_comp_level();
1883 } else {
1884 return CompLevel_none;
1885 }
1886 }
1887
1888 int Method::highest_osr_comp_level() const {
1889 const MethodCounters* mcs = method_counters();
1890 if (mcs != NULL) {
1891 return mcs->highest_osr_comp_level();
1892 } else {
1893 return CompLevel_none;
1894 }
1895 }
1896
1897 void Method::set_highest_comp_level(int level) {
1898 MethodCounters* mcs = method_counters();
1899 if (mcs != NULL) {
1900 mcs->set_highest_comp_level(level);
1901 }
1902 }
1903
1904 void Method::set_highest_osr_comp_level(int level) {
1905 MethodCounters* mcs = method_counters();
1906 if (mcs != NULL) {
1907 mcs->set_highest_osr_comp_level(level);
1908 }
1909 }
1910
1911 #if INCLUDE_JVMTI
1912
1913 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1914 _bci = bci;
1915 _name_index = m->name_index();
1916 _signature_index = m->signature_index();
1917 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1918 if (_orig_bytecode == Bytecodes::_breakpoint)
1919 _orig_bytecode = m->orig_bytecode_at(_bci);
1920 _next = NULL;
1921 }
1922
1923 void BreakpointInfo::set(Method* method) {
1924 #ifdef ASSERT
1925 {
1926 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1927 if (code == Bytecodes::_breakpoint)
1928 code = method->orig_bytecode_at(_bci);
1929 assert(orig_bytecode() == code, "original bytecode must be the same");
1930 }
1931 #endif
1932 Thread *thread = Thread::current();
1933 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1934 method->incr_number_of_breakpoints(thread);
1935 SystemDictionary::notice_modification();
1936 {
1937 // Deoptimize all dependents on this method
1938 HandleMark hm(thread);
1939 methodHandle mh(thread, method);
1940 CodeCache::flush_dependents_on_method(mh);
1941 }
1942 }
1943
1944 void BreakpointInfo::clear(Method* method) {
1945 *method->bcp_from(_bci) = orig_bytecode();
1946 assert(method->number_of_breakpoints() > 0, "must not go negative");
1947 method->decr_number_of_breakpoints(Thread::current());
1948 }
1949
1950 #endif // INCLUDE_JVMTI
1951
1952 // jmethodID handling
1953
1954 // This is a block allocating object, sort of like JNIHandleBlock, only a
1955 // lot simpler.
1956 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1957 // never get rid of it.
1958
1959 static const int min_block_size = 8;
1960
1961 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1962 friend class JNIMethodBlock;
1963 Method** _methods;
1964 int _number_of_methods;
1965 int _top;
1966 JNIMethodBlockNode* _next;
1967
1968 public:
1969
1970 JNIMethodBlockNode(int num_methods = min_block_size);
1971
1972 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1973
1974 void ensure_methods(int num_addl_methods) {
1975 if (_top < _number_of_methods) {
1976 num_addl_methods -= _number_of_methods - _top;
1977 if (num_addl_methods <= 0) {
1978 return;
1979 }
1980 }
1981 if (_next == NULL) {
1982 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1983 } else {
1984 _next->ensure_methods(num_addl_methods);
1985 }
1986 }
1987 };
1988
1989 class JNIMethodBlock : public CHeapObj<mtClass> {
1990 JNIMethodBlockNode _head;
1991 JNIMethodBlockNode *_last_free;
1992 public:
1993 static Method* const _free_method;
1994
1995 JNIMethodBlock(int initial_capacity = min_block_size)
1996 : _head(initial_capacity), _last_free(&_head) {}
1997
1998 void ensure_methods(int num_addl_methods) {
1999 _last_free->ensure_methods(num_addl_methods);
2000 }
2001
2002 Method** add_method(Method* m) {
2003 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
2004 if (b->_top < b->_number_of_methods) {
2005 // top points to the next free entry.
2006 int i = b->_top;
2007 b->_methods[i] = m;
2008 b->_top++;
2009 _last_free = b;
2010 return &(b->_methods[i]);
2011 } else if (b->_top == b->_number_of_methods) {
2012 // if the next free entry ran off the block see if there's a free entry
2013 for (int i = 0; i < b->_number_of_methods; i++) {
2014 if (b->_methods[i] == _free_method) {
2015 b->_methods[i] = m;
2016 _last_free = b;
2017 return &(b->_methods[i]);
2018 }
2019 }
2020 // Only check each block once for frees. They're very unlikely.
2021 // Increment top past the end of the block.
2022 b->_top++;
2023 }
2024 // need to allocate a next block.
2025 if (b->_next == NULL) {
2026 b->_next = _last_free = new JNIMethodBlockNode();
2027 }
2028 }
2029 guarantee(false, "Should always allocate a free block");
2030 return NULL;
2031 }
2032
2033 bool contains(Method** m) {
2034 if (m == NULL) return false;
2035 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2036 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2037 // This is a bit of extra checking, for two reasons. One is
2038 // that contains() deals with pointers that are passed in by
2039 // JNI code, so making sure that the pointer is aligned
2040 // correctly is valuable. The other is that <= and > are
2041 // technically not defined on pointers, so the if guard can
2042 // pass spuriously; no modern compiler is likely to make that
2043 // a problem, though (and if one did, the guard could also
2044 // fail spuriously, which would be bad).
2045 ptrdiff_t idx = m - b->_methods;
2046 if (b->_methods + idx == m) {
2047 return true;
2048 }
2049 }
2050 }
2051 return false; // not found
2052 }
2053
2054 // Doesn't really destroy it, just marks it as free so it can be reused.
2055 void destroy_method(Method** m) {
2056 #ifdef ASSERT
2057 assert(contains(m), "should be a methodID");
2058 #endif // ASSERT
2059 *m = _free_method;
2060 }
2061
2062 // During class unloading the methods are cleared, which is different
2063 // than freed.
2064 void clear_all_methods() {
2065 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2066 for (int i = 0; i< b->_number_of_methods; i++) {
2067 b->_methods[i] = NULL;
2068 }
2069 }
2070 }
2071 #ifndef PRODUCT
2072 int count_methods() {
2073 // count all allocated methods
2074 int count = 0;
2075 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2076 for (int i = 0; i< b->_number_of_methods; i++) {
2077 if (b->_methods[i] != _free_method) count++;
2078 }
2079 }
2080 return count;
2081 }
2082 #endif // PRODUCT
2083 };
2084
2085 // Something that can't be mistaken for an address or a markOop
2086 Method* const JNIMethodBlock::_free_method = (Method*)55;
2087
2088 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
2089 _number_of_methods = MAX2(num_methods, min_block_size);
2090 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2091 for (int i = 0; i < _number_of_methods; i++) {
2092 _methods[i] = JNIMethodBlock::_free_method;
2093 }
2094 }
2095
2096 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2097 ClassLoaderData* cld = loader_data;
2098 if (!SafepointSynchronize::is_at_safepoint()) {
2099 // Have to add jmethod_ids() to class loader data thread-safely.
2100 // Also have to add the method to the list safely, which the cld lock
2101 // protects as well.
2102 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2103 if (cld->jmethod_ids() == NULL) {
2104 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2105 } else {
2106 cld->jmethod_ids()->ensure_methods(capacity);
2107 }
2108 } else {
2109 // At safepoint, we are single threaded and can set this.
2110 if (cld->jmethod_ids() == NULL) {
2111 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2112 } else {
2113 cld->jmethod_ids()->ensure_methods(capacity);
2114 }
2115 }
2116 }
2117
2118 // Add a method id to the jmethod_ids
2119 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2120 ClassLoaderData* cld = loader_data;
2121
2122 if (!SafepointSynchronize::is_at_safepoint()) {
2123 // Have to add jmethod_ids() to class loader data thread-safely.
2124 // Also have to add the method to the list safely, which the cld lock
2125 // protects as well.
2126 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2127 if (cld->jmethod_ids() == NULL) {
2128 cld->set_jmethod_ids(new JNIMethodBlock());
2129 }
2130 // jmethodID is a pointer to Method*
2131 return (jmethodID)cld->jmethod_ids()->add_method(m);
2132 } else {
2133 // At safepoint, we are single threaded and can set this.
2134 if (cld->jmethod_ids() == NULL) {
2135 cld->set_jmethod_ids(new JNIMethodBlock());
2136 }
2137 // jmethodID is a pointer to Method*
2138 return (jmethodID)cld->jmethod_ids()->add_method(m);
2139 }
2140 }
2141
2142 // Mark a jmethodID as free. This is called when there is a data race in
2143 // InstanceKlass while creating the jmethodID cache.
2144 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2145 ClassLoaderData* cld = loader_data;
2146 Method** ptr = (Method**)m;
2147 assert(cld->jmethod_ids() != NULL, "should have method handles");
2148 cld->jmethod_ids()->destroy_method(ptr);
2149 }
2150
2151 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2152 // Can't assert the method_holder is the same because the new method has the
2153 // scratch method holder.
2154 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2155 == new_method->method_holder()->class_loader(),
2156 "changing to a different class loader");
2157 // Just change the method in place, jmethodID pointer doesn't change.
2158 *((Method**)jmid) = new_method;
2159 }
2160
2161 bool Method::is_method_id(jmethodID mid) {
2162 Method* m = resolve_jmethod_id(mid);
2163 assert(m != NULL, "should be called with non-null method");
2164 InstanceKlass* ik = m->method_holder();
2165 ClassLoaderData* cld = ik->class_loader_data();
2166 if (cld->jmethod_ids() == NULL) return false;
2167 return (cld->jmethod_ids()->contains((Method**)mid));
2168 }
2169
2170 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2171 if (mid == NULL) return NULL;
2172 Method* o = resolve_jmethod_id(mid);
2173 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2174 return NULL;
2175 }
2176 return o;
2177 };
2178
2179 void Method::set_on_stack(const bool value) {
2180 // Set both the method itself and its constant pool. The constant pool
2181 // on stack means some method referring to it is also on the stack.
2182 constants()->set_on_stack(value);
2183
2184 bool already_set = on_stack();
2185 _access_flags.set_on_stack(value);
2186 if (value && !already_set) {
2187 MetadataOnStackMark::record(this);
2188 }
2189 }
2190
2191 // Called when the class loader is unloaded to make all methods weak.
2192 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2193 loader_data->jmethod_ids()->clear_all_methods();
2194 }
2195
2196 bool Method::has_method_vptr(const void* ptr) {
2197 Method m;
2198 // This assumes that the vtbl pointer is the first word of a C++ object.
2199 return dereference_vptr(&m) == dereference_vptr(ptr);
2200 }
2201
2202 // Check that this pointer is valid by checking that the vtbl pointer matches
2203 bool Method::is_valid_method() const {
2204 if (this == NULL) {
2205 return false;
2206 } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2207 // Quick sanity check on pointer.
2208 return false;
2209 } else if (MetaspaceShared::is_in_shared_space(this)) {
2210 return MetaspaceShared::is_valid_shared_method(this);
2211 } else if (Metaspace::contains_non_shared(this)) {
2212 return has_method_vptr((const void*)this);
2213 } else {
2214 return false;
2215 }
2216 }
2217
2218 #ifndef PRODUCT
2219 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
2220 out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2221 }
2222 #endif // PRODUCT
2223
2224
2225 // Printing
2226
2227 #ifndef PRODUCT
2228
2229 void Method::print_on(outputStream* st) const {
2230 ResourceMark rm;
2231 assert(is_method(), "must be method");
2232 st->print_cr("%s", internal_name());
2233 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2234 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2235 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2236 constants()->print_value_on(st); st->cr();
2237 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2238 st->print (" - name: "); name()->print_value_on(st); st->cr();
2239 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2240 st->print_cr(" - max stack: %d", max_stack());
2241 st->print_cr(" - max locals: %d", max_locals());
2242 st->print_cr(" - size of params: %d", size_of_parameters());
2243 st->print_cr(" - method size: %d", method_size());
2244 if (intrinsic_id() != vmIntrinsics::_none)
2245 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2246 if (highest_comp_level() != CompLevel_none)
2247 st->print_cr(" - highest level: %d", highest_comp_level());
2248 st->print_cr(" - vtable index: %d", _vtable_index);
2249 if (valid_itable_index())
2250 st->print_cr(" - itable index: %d", itable_index());
2251 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2252 st->print( " - adapters: ");
2253 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2254 if (a == NULL)
2255 st->print_cr(INTPTR_FORMAT, p2i(a));
2256 else
2257 a->print_adapter_on(st);
2258 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2259 st->print_cr(" - code size: %d", code_size());
2260 if (code_size() != 0) {
2261 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2262 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2263 }
2264 if (method_data() != NULL) {
2265 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2266 }
2267 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2268 if (checked_exceptions_length() > 0) {
2269 CheckedExceptionElement* table = checked_exceptions_start();
2270 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2271 if (Verbose) {
2272 for (int i = 0; i < checked_exceptions_length(); i++) {
2273 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2274 }
2275 }
2276 }
2277 if (has_linenumber_table()) {
2278 u_char* table = compressed_linenumber_table();
2279 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2280 if (Verbose) {
2281 CompressedLineNumberReadStream stream(table);
2282 while (stream.read_pair()) {
2283 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2284 }
2285 }
2286 }
2287 st->print_cr(" - localvar length: %d", localvariable_table_length());
2288 if (localvariable_table_length() > 0) {
2289 LocalVariableTableElement* table = localvariable_table_start();
2290 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2291 if (Verbose) {
2292 for (int i = 0; i < localvariable_table_length(); i++) {
2293 int bci = table[i].start_bci;
2294 int len = table[i].length;
2295 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2296 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2297 int slot = table[i].slot;
2298 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2299 }
2300 }
2301 }
2302 if (code() != NULL) {
2303 st->print (" - compiled code: ");
2304 code()->print_value_on(st);
2305 }
2306 if (is_native()) {
2307 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2308 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2309 }
2310 }
2311
2312 void Method::print_linkage_flags(outputStream* st) {
2313 access_flags().print_on(st);
2314 if (is_default_method()) {
2315 st->print("default ");
2316 }
2317 if (is_overpass()) {
2318 st->print("overpass ");
2319 }
2320 }
2321 #endif //PRODUCT
2322
2323 void Method::print_value_on(outputStream* st) const {
2324 assert(is_method(), "must be method");
2325 st->print("%s", internal_name());
2326 print_address_on(st);
2327 st->print(" ");
2328 if (WizardMode) access_flags().print_on(st);
2329 name()->print_value_on(st);
2330 st->print(" ");
2331 signature()->print_value_on(st);
2332 st->print(" in ");
2333 method_holder()->print_value_on(st);
2334 if (WizardMode) st->print("#%d", _vtable_index);
2335 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2336 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2337 }
2338
2339 #if INCLUDE_SERVICES
2340 // Size Statistics
2341 void Method::collect_statistics(KlassSizeStats *sz) const {
2342 int mysize = sz->count(this);
2343 sz->_method_bytes += mysize;
2344 sz->_method_all_bytes += mysize;
2345 sz->_rw_bytes += mysize;
2346
2347 if (constMethod()) {
2348 constMethod()->collect_statistics(sz);
2349 }
2350 if (method_data()) {
2351 method_data()->collect_statistics(sz);
2352 }
2353 }
2354 #endif // INCLUDE_SERVICES
2355
2356 // LogTouchedMethods and PrintTouchedMethods
2357
2358 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2359 // the Method may be garbage collected. Let's roll our own hash table.
2360 class TouchedMethodRecord : CHeapObj<mtTracing> {
2361 public:
2362 // It's OK to store Symbols here because they will NOT be GC'ed if
2363 // LogTouchedMethods is enabled.
2364 TouchedMethodRecord* _next;
2365 Symbol* _class_name;
2366 Symbol* _method_name;
2367 Symbol* _method_signature;
2368 };
2369
2370 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2371 static TouchedMethodRecord** _touched_method_table = NULL;
2372
2373 void Method::log_touched(TRAPS) {
2374
2375 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2376 Symbol* my_class = klass_name();
2377 Symbol* my_name = name();
2378 Symbol* my_sig = signature();
2379
2380 unsigned int hash = my_class->identity_hash() +
2381 my_name->identity_hash() +
2382 my_sig->identity_hash();
2383 juint index = juint(hash) % table_size;
2384
2385 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2386 if (_touched_method_table == NULL) {
2387 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2388 mtTracing, CURRENT_PC);
2389 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2390 }
2391
2392 TouchedMethodRecord* ptr = _touched_method_table[index];
2393 while (ptr) {
2394 if (ptr->_class_name == my_class &&
2395 ptr->_method_name == my_name &&
2396 ptr->_method_signature == my_sig) {
2397 return;
2398 }
2399 if (ptr->_next == NULL) break;
2400 ptr = ptr->_next;
2401 }
2402 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2403 my_class->set_permanent(); // prevent reclaimed by GC
2404 my_name->set_permanent();
2405 my_sig->set_permanent();
2406 nptr->_class_name = my_class;
2407 nptr->_method_name = my_name;
2408 nptr->_method_signature = my_sig;
2409 nptr->_next = NULL;
2410
2411 if (ptr == NULL) {
2412 // first
2413 _touched_method_table[index] = nptr;
2414 } else {
2415 ptr->_next = nptr;
2416 }
2417 }
2418
2419 void Method::print_touched_methods(outputStream* out) {
2420 MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2421 out->print_cr("# Method::print_touched_methods version 1");
2422 if (_touched_method_table) {
2423 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2424 TouchedMethodRecord* ptr = _touched_method_table[i];
2425 while(ptr) {
2426 ptr->_class_name->print_symbol_on(out); out->print(".");
2427 ptr->_method_name->print_symbol_on(out); out->print(":");
2428 ptr->_method_signature->print_symbol_on(out); out->cr();
2429 ptr = ptr->_next;
2430 }
2431 }
2432 }
2433 }
2434
2435 // Verification
2436
2437 void Method::verify_on(outputStream* st) {
2438 guarantee(is_method(), "object must be method");
2439 guarantee(constants()->is_constantPool(), "should be constant pool");
2440 guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2441 MethodData* md = method_data();
2442 guarantee(md == NULL ||
2443 md->is_methodData(), "should be method data");
2444 }