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