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