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 is_object_initializer() || 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 bool Method::is_object_initializer() const {
647 return name() == vmSymbols::object_initializer_name();
648 }
649
650 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
651 int length = method->checked_exceptions_length();
652 if (length == 0) { // common case
653 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
654 } else {
655 methodHandle h_this(THREAD, method);
656 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
657 objArrayHandle mirrors (THREAD, m_oop);
658 for (int i = 0; i < length; i++) {
659 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
660 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
661 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
662 mirrors->obj_at_put(i, k->java_mirror());
663 }
664 return mirrors;
665 }
666 };
667
668
669 int Method::line_number_from_bci(int bci) const {
670 if (bci == SynchronizationEntryBCI) bci = 0;
671 assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
672 int best_bci = 0;
673 int best_line = -1;
674
675 if (has_linenumber_table()) {
676 // The line numbers are a short array of 2-tuples [start_pc, line_number].
677 // Not necessarily sorted and not necessarily one-to-one.
678 CompressedLineNumberReadStream stream(compressed_linenumber_table());
679 while (stream.read_pair()) {
680 if (stream.bci() == bci) {
681 // perfect match
682 return stream.line();
683 } else {
684 // update best_bci/line
685 if (stream.bci() < bci && stream.bci() >= best_bci) {
686 best_bci = stream.bci();
687 best_line = stream.line();
688 }
689 }
690 }
691 }
692 return best_line;
693 }
694
695
696 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
697 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
698 Thread *thread = Thread::current();
699 Symbol* klass_name = constants()->klass_name_at(klass_index);
700 Handle loader(thread, method_holder()->class_loader());
701 Handle prot (thread, method_holder()->protection_domain());
702 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
703 } else {
704 return true;
705 }
706 }
707
708
709 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
710 int klass_index = constants()->klass_ref_index_at(refinfo_index);
711 if (must_be_resolved) {
712 // Make sure klass is resolved in constantpool.
713 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
714 }
715 return is_klass_loaded_by_klass_index(klass_index);
716 }
717
718
719 void Method::set_native_function(address function, bool post_event_flag) {
720 assert(function != NULL, "use clear_native_function to unregister natives");
721 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
722 address* native_function = native_function_addr();
723
724 // We can see racers trying to place the same native function into place. Once
725 // is plenty.
726 address current = *native_function;
727 if (current == function) return;
728 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
729 function != NULL) {
730 // native_method_throw_unsatisfied_link_error_entry() should only
731 // be passed when post_event_flag is false.
732 assert(function !=
733 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
734 "post_event_flag mis-match");
735
736 // post the bind event, and possible change the bind function
737 JvmtiExport::post_native_method_bind(this, &function);
738 }
739 *native_function = function;
740 // This function can be called more than once. We must make sure that we always
741 // use the latest registered method -> check if a stub already has been generated.
742 // If so, we have to make it not_entrant.
743 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
744 if (nm != NULL) {
745 nm->make_not_entrant();
746 }
747 }
748
749
750 bool Method::has_native_function() const {
751 if (is_method_handle_intrinsic())
752 return false; // special-cased in SharedRuntime::generate_native_wrapper
753 address func = native_function();
754 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
755 }
756
757
758 void Method::clear_native_function() {
759 // Note: is_method_handle_intrinsic() is allowed here.
760 set_native_function(
761 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
762 !native_bind_event_is_interesting);
763 clear_code();
764 }
765
766 address Method::critical_native_function() {
767 methodHandle mh(this);
768 return NativeLookup::lookup_critical_entry(mh);
769 }
770
771
772 void Method::set_signature_handler(address handler) {
773 address* signature_handler = signature_handler_addr();
774 *signature_handler = handler;
775 }
776
777
778 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
779 if (PrintCompilation && report) {
780 ttyLocker ttyl;
781 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
782 if (comp_level == CompLevel_all) {
783 tty->print("all levels ");
784 } else {
785 tty->print("levels ");
786 for (int i = (int)CompLevel_none; i <= comp_level; i++) {
787 tty->print("%d ", i);
788 }
789 }
790 this->print_short_name(tty);
791 int size = this->code_size();
792 if (size > 0) {
793 tty->print(" (%d bytes)", size);
794 }
795 if (reason != NULL) {
796 tty->print(" %s", reason);
797 }
798 tty->cr();
799 }
800 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
801 ttyLocker ttyl;
802 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
803 os::current_thread_id(), is_osr, comp_level);
804 if (reason != NULL) {
805 xtty->print(" reason=\'%s\'", reason);
806 }
807 xtty->method(this);
808 xtty->stamp();
809 xtty->end_elem();
810 }
811 }
812
813 bool Method::is_always_compilable() const {
814 // Generated adapters must be compiled
815 if (is_method_handle_intrinsic() && is_synthetic()) {
816 assert(!is_not_c1_compilable(), "sanity check");
817 assert(!is_not_c2_compilable(), "sanity check");
818 return true;
819 }
820
821 return false;
822 }
823
824 bool Method::is_not_compilable(int comp_level) const {
825 if (number_of_breakpoints() > 0)
826 return true;
827 if (is_always_compilable())
828 return false;
829 if (comp_level == CompLevel_any)
830 return is_not_c1_compilable() || is_not_c2_compilable();
831 if (is_c1_compile(comp_level))
832 return is_not_c1_compilable();
833 if (is_c2_compile(comp_level))
834 return is_not_c2_compilable();
835 return false;
836 }
837
838 // call this when compiler finds that this method is not compilable
839 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
840 if (is_always_compilable()) {
841 // Don't mark a method which should be always compilable
842 return;
843 }
844 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
845 if (comp_level == CompLevel_all) {
846 set_not_c1_compilable();
847 set_not_c2_compilable();
848 } else {
849 if (is_c1_compile(comp_level))
850 set_not_c1_compilable();
851 if (is_c2_compile(comp_level))
852 set_not_c2_compilable();
853 }
854 CompilationPolicy::policy()->disable_compilation(this);
855 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
856 }
857
858 bool Method::is_not_osr_compilable(int comp_level) const {
859 if (is_not_compilable(comp_level))
860 return true;
861 if (comp_level == CompLevel_any)
862 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
863 if (is_c1_compile(comp_level))
864 return is_not_c1_osr_compilable();
865 if (is_c2_compile(comp_level))
866 return is_not_c2_osr_compilable();
867 return false;
868 }
869
870 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
871 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
872 if (comp_level == CompLevel_all) {
873 set_not_c1_osr_compilable();
874 set_not_c2_osr_compilable();
875 } else {
876 if (is_c1_compile(comp_level))
877 set_not_c1_osr_compilable();
878 if (is_c2_compile(comp_level))
879 set_not_c2_osr_compilable();
880 }
881 CompilationPolicy::policy()->disable_compilation(this);
882 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
883 }
884
885 // Revert to using the interpreter and clear out the nmethod
886 void Method::clear_code() {
887
888 // this may be NULL if c2i adapters have not been made yet
889 // Only should happen at allocate time.
890 if (adapter() == NULL) {
891 _from_compiled_entry = NULL;
892 } else {
893 _from_compiled_entry = adapter()->get_c2i_entry();
894 }
895 OrderAccess::storestore();
896 _from_interpreted_entry = _i2i_entry;
897 OrderAccess::storestore();
898 _code = NULL;
899 }
900
901 #if INCLUDE_CDS
902 // Called by class data sharing to remove any entry points (which are not shared)
903 void Method::unlink_method() {
904 _code = NULL;
905
906 assert(DumpSharedSpaces, "dump time only");
907 // Set the values to what they should be at run time. Note that
908 // this Method can no longer be executed during dump time.
909 _i2i_entry = Interpreter::entry_for_cds_method(this);
910 _from_interpreted_entry = _i2i_entry;
911
912 if (is_native()) {
913 *native_function_addr() = NULL;
914 set_signature_handler(NULL);
915 }
916 NOT_PRODUCT(set_compiled_invocation_count(0);)
917
918 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
919 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
920 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
921 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
922
923
924 // In case of DumpSharedSpaces, _method_data should always be NULL.
925 assert(_method_data == NULL, "unexpected method data?");
926
927 set_method_data(NULL);
928 clear_method_counters();
929 }
930 #endif
931
932 // Called when the method_holder is getting linked. Setup entrypoints so the method
933 // is ready to be called from interpreter, compiler, and vtables.
934 void Method::link_method(const methodHandle& h_method, TRAPS) {
935 // If the code cache is full, we may reenter this function for the
936 // leftover methods that weren't linked.
937 if (is_shared()) {
938 if (adapter() != NULL) return;
939 } else {
940 if (_i2i_entry != NULL) return;
941
942 assert(adapter() == NULL, "init'd to NULL" );
943 }
944 assert( _code == NULL, "nothing compiled yet" );
945
946 // Setup interpreter entrypoint
947 assert(this == h_method(), "wrong h_method()" );
948 address entry;
949
950 if (this->is_shared()) {
951 entry = Interpreter::entry_for_cds_method(h_method);
952 } else {
953 entry = Interpreter::entry_for_method(h_method);
954 }
955 assert(entry != NULL, "interpreter entry must be non-null");
956 if (is_shared()) {
957 assert(entry == _i2i_entry && entry == _from_interpreted_entry,
958 "should be correctly set during dump time");
959 } else {
960 // Sets both _i2i_entry and _from_interpreted_entry
961 set_interpreter_entry(entry);
962 }
963
964 // Don't overwrite already registered native entries.
965 if (is_native() && !has_native_function()) {
966 set_native_function(
967 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
968 !native_bind_event_is_interesting);
969 }
970
971 // Setup compiler entrypoint. This is made eagerly, so we do not need
972 // special handling of vtables. An alternative is to make adapters more
973 // lazily by calling make_adapter() from from_compiled_entry() for the
974 // normal calls. For vtable calls life gets more complicated. When a
975 // call-site goes mega-morphic we need adapters in all methods which can be
976 // called from the vtable. We need adapters on such methods that get loaded
977 // later. Ditto for mega-morphic itable calls. If this proves to be a
978 // problem we'll make these lazily later.
979 (void) make_adapters(h_method, CHECK);
980
981 // ONLY USE the h_method now as make_adapter may have blocked
982
983 }
984
985 address Method::make_adapters(methodHandle mh, TRAPS) {
986 // Adapters for compiled code are made eagerly here. They are fairly
987 // small (generally < 100 bytes) and quick to make (and cached and shared)
988 // so making them eagerly shouldn't be too expensive.
989 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
990 if (adapter == NULL ) {
991 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
992 }
993
994 if (mh->is_shared()) {
995 assert(mh->adapter() == adapter, "must be");
996 assert(mh->_from_compiled_entry != NULL, "must be"); // FIXME, the instructions also not NULL
997 } else {
998 mh->set_adapter_entry(adapter);
999 mh->_from_compiled_entry = adapter->get_c2i_entry();
1000 }
1001 return adapter->get_c2i_entry();
1002 }
1003
1004 void Method::restore_unshareable_info(TRAPS) {
1005 // Since restore_unshareable_info can be called more than once for a method, don't
1006 // redo any work. If this field is restored, there is nothing to do.
1007 if (_from_compiled_entry == NULL) {
1008 // restore method's vtable by calling a virtual function
1009 restore_vtable();
1010
1011 methodHandle mh(THREAD, this);
1012 link_method(mh, CHECK);
1013 }
1014 }
1015
1016 volatile address Method::from_compiled_entry_no_trampoline() const {
1017 nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
1018 if (code) {
1019 return code->verified_entry_point();
1020 } else {
1021 return adapter()->get_c2i_entry();
1022 }
1023 }
1024
1025 // The verified_code_entry() must be called when a invoke is resolved
1026 // on this method.
1027
1028 // It returns the compiled code entry point, after asserting not null.
1029 // This function is called after potential safepoints so that nmethod
1030 // or adapter that it points to is still live and valid.
1031 // This function must not hit a safepoint!
1032 address Method::verified_code_entry() {
1033 debug_only(NoSafepointVerifier nsv;)
1034 assert(_from_compiled_entry != NULL, "must be set");
1035 return _from_compiled_entry;
1036 }
1037
1038 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1039 // (could be racing a deopt).
1040 // Not inline to avoid circular ref.
1041 bool Method::check_code() const {
1042 // cached in a register or local. There's a race on the value of the field.
1043 CompiledMethod *code = (CompiledMethod *)OrderAccess::load_ptr_acquire(&_code);
1044 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1045 }
1046
1047 // Install compiled code. Instantly it can execute.
1048 void Method::set_code(methodHandle mh, CompiledMethod *code) {
1049 assert( code, "use clear_code to remove code" );
1050 assert( mh->check_code(), "" );
1051
1052 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1053
1054 // These writes must happen in this order, because the interpreter will
1055 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1056 // which jumps to _from_compiled_entry.
1057 mh->_code = code; // Assign before allowing compiled code to exec
1058
1059 int comp_level = code->comp_level();
1060 // In theory there could be a race here. In practice it is unlikely
1061 // and not worth worrying about.
1062 if (comp_level > mh->highest_comp_level()) {
1063 mh->set_highest_comp_level(comp_level);
1064 }
1065
1066 OrderAccess::storestore();
1067 #ifdef SHARK
1068 mh->_from_interpreted_entry = code->insts_begin();
1069 #else //!SHARK
1070 mh->_from_compiled_entry = code->verified_entry_point();
1071 OrderAccess::storestore();
1072 // Instantly compiled code can execute.
1073 if (!mh->is_method_handle_intrinsic())
1074 mh->_from_interpreted_entry = mh->get_i2c_entry();
1075 #endif //!SHARK
1076 }
1077
1078
1079 bool Method::is_overridden_in(Klass* k) const {
1080 InstanceKlass* ik = InstanceKlass::cast(k);
1081
1082 if (ik->is_interface()) return false;
1083
1084 // If method is an interface, we skip it - except if it
1085 // is a miranda method
1086 if (method_holder()->is_interface()) {
1087 // Check that method is not a miranda method
1088 if (ik->lookup_method(name(), signature()) == NULL) {
1089 // No implementation exist - so miranda method
1090 return false;
1091 }
1092 return true;
1093 }
1094
1095 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1096 assert(ik->vtable() != NULL, "vtable should exist");
1097 if (!has_vtable_index()) {
1098 return false;
1099 } else {
1100 Method* vt_m = ik->method_at_vtable(vtable_index());
1101 return vt_m != this;
1102 }
1103 }
1104
1105
1106 // give advice about whether this Method* should be cached or not
1107 bool Method::should_not_be_cached() const {
1108 if (is_old()) {
1109 // This method has been redefined. It is either EMCP or obsolete
1110 // and we don't want to cache it because that would pin the method
1111 // down and prevent it from being collectible if and when it
1112 // finishes executing.
1113 return true;
1114 }
1115
1116 // caching this method should be just fine
1117 return false;
1118 }
1119
1120
1121 /**
1122 * Returns true if this is one of the specially treated methods for
1123 * security related stack walks (like Reflection.getCallerClass).
1124 */
1125 bool Method::is_ignored_by_security_stack_walk() const {
1126 if (intrinsic_id() == vmIntrinsics::_invoke) {
1127 // This is Method.invoke() -- ignore it
1128 return true;
1129 }
1130 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1131 // This is an auxilary frame -- ignore it
1132 return true;
1133 }
1134 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1135 // This is an internal adapter frame for method handles -- ignore it
1136 return true;
1137 }
1138 return false;
1139 }
1140
1141
1142 // Constant pool structure for invoke methods:
1143 enum {
1144 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1145 _imcp_invoke_signature, // utf8: (variable Symbol*)
1146 _imcp_limit
1147 };
1148
1149 // Test if this method is an MH adapter frame generated by Java code.
1150 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1151 bool Method::is_compiled_lambda_form() const {
1152 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1153 }
1154
1155 // Test if this method is an internal MH primitive method.
1156 bool Method::is_method_handle_intrinsic() const {
1157 vmIntrinsics::ID iid = intrinsic_id();
1158 return (MethodHandles::is_signature_polymorphic(iid) &&
1159 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1160 }
1161
1162 bool Method::has_member_arg() const {
1163 vmIntrinsics::ID iid = intrinsic_id();
1164 return (MethodHandles::is_signature_polymorphic(iid) &&
1165 MethodHandles::has_member_arg(iid));
1166 }
1167
1168 // Make an instance of a signature-polymorphic internal MH primitive.
1169 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1170 Symbol* signature,
1171 TRAPS) {
1172 ResourceMark rm;
1173 methodHandle empty;
1174
1175 KlassHandle holder = SystemDictionary::MethodHandle_klass();
1176 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1177 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1178 if (TraceMethodHandles) {
1179 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1180 }
1181
1182 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1183 name->increment_refcount();
1184 signature->increment_refcount();
1185
1186 int cp_length = _imcp_limit;
1187 ClassLoaderData* loader_data = holder->class_loader_data();
1188 constantPoolHandle cp;
1189 {
1190 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1191 cp = constantPoolHandle(THREAD, cp_oop);
1192 }
1193 cp->set_pool_holder(InstanceKlass::cast(holder()));
1194 cp->symbol_at_put(_imcp_invoke_name, name);
1195 cp->symbol_at_put(_imcp_invoke_signature, signature);
1196 cp->set_has_preresolution();
1197
1198 // decide on access bits: public or not?
1199 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1200 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1201 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1202 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1203
1204 methodHandle m;
1205 {
1206 InlineTableSizes sizes;
1207 Method* m_oop = Method::allocate(loader_data, 0,
1208 accessFlags_from(flags_bits), &sizes,
1209 ConstMethod::NORMAL, CHECK_(empty));
1210 m = methodHandle(THREAD, m_oop);
1211 }
1212 m->set_constants(cp());
1213 m->set_name_index(_imcp_invoke_name);
1214 m->set_signature_index(_imcp_invoke_signature);
1215 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1216 assert(m->signature() == signature, "");
1217 ResultTypeFinder rtf(signature);
1218 m->constMethod()->set_result_type(rtf.type());
1219 m->compute_size_of_parameters(THREAD);
1220 m->init_intrinsic_id();
1221 assert(m->is_method_handle_intrinsic(), "");
1222 #ifdef ASSERT
1223 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1224 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1225 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1226 #endif //ASSERT
1227
1228 // Finally, set up its entry points.
1229 assert(m->can_be_statically_bound(), "");
1230 m->set_vtable_index(Method::nonvirtual_vtable_index);
1231 m->link_method(m, CHECK_(empty));
1232
1233 if (TraceMethodHandles && (Verbose || WizardMode)) {
1234 ttyLocker ttyl;
1235 m->print_on(tty);
1236 }
1237
1238 return m;
1239 }
1240
1241 Klass* Method::check_non_bcp_klass(Klass* klass) {
1242 if (klass != NULL && klass->class_loader() != NULL) {
1243 if (klass->is_objArray_klass())
1244 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1245 return klass;
1246 }
1247 return NULL;
1248 }
1249
1250
1251 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1252 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1253 // Code below does not work for native methods - they should never get rewritten anyway
1254 assert(!m->is_native(), "cannot rewrite native methods");
1255 // Allocate new Method*
1256 AccessFlags flags = m->access_flags();
1257
1258 ConstMethod* cm = m->constMethod();
1259 int checked_exceptions_len = cm->checked_exceptions_length();
1260 int localvariable_len = cm->localvariable_table_length();
1261 int exception_table_len = cm->exception_table_length();
1262 int method_parameters_len = cm->method_parameters_length();
1263 int method_annotations_len = cm->method_annotations_length();
1264 int parameter_annotations_len = cm->parameter_annotations_length();
1265 int type_annotations_len = cm->type_annotations_length();
1266 int default_annotations_len = cm->default_annotations_length();
1267
1268 InlineTableSizes sizes(
1269 localvariable_len,
1270 new_compressed_linenumber_size,
1271 exception_table_len,
1272 checked_exceptions_len,
1273 method_parameters_len,
1274 cm->generic_signature_index(),
1275 method_annotations_len,
1276 parameter_annotations_len,
1277 type_annotations_len,
1278 default_annotations_len,
1279 0);
1280
1281 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1282 Method* newm_oop = Method::allocate(loader_data,
1283 new_code_length,
1284 flags,
1285 &sizes,
1286 m->method_type(),
1287 CHECK_(methodHandle()));
1288 methodHandle newm (THREAD, newm_oop);
1289
1290 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1291 ConstMethod* newcm = newm->constMethod();
1292 int new_const_method_size = newm->constMethod()->size();
1293
1294 memcpy(newm(), m(), sizeof(Method));
1295
1296 // Create shallow copy of ConstMethod.
1297 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1298
1299 // Reset correct method/const method, method size, and parameter info
1300 newm->set_constMethod(newcm);
1301 newm->constMethod()->set_code_size(new_code_length);
1302 newm->constMethod()->set_constMethod_size(new_const_method_size);
1303 assert(newm->code_size() == new_code_length, "check");
1304 assert(newm->method_parameters_length() == method_parameters_len, "check");
1305 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1306 assert(newm->exception_table_length() == exception_table_len, "check");
1307 assert(newm->localvariable_table_length() == localvariable_len, "check");
1308 // Copy new byte codes
1309 memcpy(newm->code_base(), new_code, new_code_length);
1310 // Copy line number table
1311 if (new_compressed_linenumber_size > 0) {
1312 memcpy(newm->compressed_linenumber_table(),
1313 new_compressed_linenumber_table,
1314 new_compressed_linenumber_size);
1315 }
1316 // Copy method_parameters
1317 if (method_parameters_len > 0) {
1318 memcpy(newm->method_parameters_start(),
1319 m->method_parameters_start(),
1320 method_parameters_len * sizeof(MethodParametersElement));
1321 }
1322 // Copy checked_exceptions
1323 if (checked_exceptions_len > 0) {
1324 memcpy(newm->checked_exceptions_start(),
1325 m->checked_exceptions_start(),
1326 checked_exceptions_len * sizeof(CheckedExceptionElement));
1327 }
1328 // Copy exception table
1329 if (exception_table_len > 0) {
1330 memcpy(newm->exception_table_start(),
1331 m->exception_table_start(),
1332 exception_table_len * sizeof(ExceptionTableElement));
1333 }
1334 // Copy local variable number table
1335 if (localvariable_len > 0) {
1336 memcpy(newm->localvariable_table_start(),
1337 m->localvariable_table_start(),
1338 localvariable_len * sizeof(LocalVariableTableElement));
1339 }
1340 // Copy stackmap table
1341 if (m->has_stackmap_table()) {
1342 int code_attribute_length = m->stackmap_data()->length();
1343 Array<u1>* stackmap_data =
1344 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1345 memcpy((void*)stackmap_data->adr_at(0),
1346 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1347 newm->set_stackmap_data(stackmap_data);
1348 }
1349
1350 // copy annotations over to new method
1351 newcm->copy_annotations_from(cm);
1352 return newm;
1353 }
1354
1355 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1356 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1357 // because we are not loading from core libraries
1358 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1359 // which does not use the class default class loader so we check for its loader here
1360 const InstanceKlass* ik = InstanceKlass::cast(holder);
1361 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1362 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1363 }
1364
1365 // see if the klass name is well-known:
1366 Symbol* klass_name = ik->name();
1367 return vmSymbols::find_sid(klass_name);
1368 }
1369
1370 void Method::init_intrinsic_id() {
1371 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1372 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1373 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1374 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1375
1376 // the klass name is well-known:
1377 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1378 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1379
1380 // ditto for method and signature:
1381 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1382 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1383 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1384 && name_id == vmSymbols::NO_SID) {
1385 return;
1386 }
1387 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1388 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1389 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1390 && sig_id == vmSymbols::NO_SID) {
1391 return;
1392 }
1393 jshort flags = access_flags().as_short();
1394
1395 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1396 if (id != vmIntrinsics::_none) {
1397 set_intrinsic_id(id);
1398 if (id == vmIntrinsics::_Class_cast) {
1399 // Even if the intrinsic is rejected, we want to inline this simple method.
1400 set_force_inline(true);
1401 }
1402 return;
1403 }
1404
1405 // A few slightly irregular cases:
1406 switch (klass_id) {
1407 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1408 // Second chance: check in regular Math.
1409 switch (name_id) {
1410 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1411 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1412 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1413 // pretend it is the corresponding method in the non-strict class:
1414 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1415 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1416 break;
1417 }
1418 break;
1419
1420 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1421 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1422 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1423 if (!is_native()) break;
1424 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1425 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1426 id = vmIntrinsics::_none;
1427 break;
1428 }
1429
1430 if (id != vmIntrinsics::_none) {
1431 // Set up its iid. It is an alias method.
1432 set_intrinsic_id(id);
1433 return;
1434 }
1435 }
1436
1437 // These two methods are static since a GC may move the Method
1438 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1439 if (!THREAD->can_call_java()) {
1440 // There is nothing useful this routine can do from within the Compile thread.
1441 // Hopefully, the signature contains only well-known classes.
1442 // We could scan for this and return true/false, but the caller won't care.
1443 return false;
1444 }
1445 bool sig_is_loaded = true;
1446 Handle class_loader(THREAD, m->method_holder()->class_loader());
1447 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1448 ResourceMark rm(THREAD);
1449 Symbol* signature = m->signature();
1450 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1451 if (ss.is_object()) {
1452 Symbol* sym = ss.as_symbol(CHECK_(false));
1453 Symbol* name = sym;
1454 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1455 protection_domain, THREAD);
1456 // We are loading classes eagerly. If a ClassNotFoundException or
1457 // a LinkageError was generated, be sure to ignore it.
1458 if (HAS_PENDING_EXCEPTION) {
1459 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1460 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1461 CLEAR_PENDING_EXCEPTION;
1462 } else {
1463 return false;
1464 }
1465 }
1466 if( klass == NULL) { sig_is_loaded = false; }
1467 }
1468 }
1469 return sig_is_loaded;
1470 }
1471
1472 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
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.type() == T_OBJECT) {
1479 Symbol* name = ss.as_symbol_or_null();
1480 if (name == NULL) return true;
1481 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1482 if (klass == NULL) return true;
1483 }
1484 }
1485 return false;
1486 }
1487
1488 // Exposed so field engineers can debug VM
1489 void Method::print_short_name(outputStream* st) {
1490 ResourceMark rm;
1491 #ifdef PRODUCT
1492 st->print(" %s::", method_holder()->external_name());
1493 #else
1494 st->print(" %s::", method_holder()->internal_name());
1495 #endif
1496 name()->print_symbol_on(st);
1497 if (WizardMode) signature()->print_symbol_on(st);
1498 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1499 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1500 }
1501
1502 // Comparer for sorting an object array containing
1503 // Method*s.
1504 static int method_comparator(Method* a, Method* b) {
1505 return a->name()->fast_compare(b->name());
1506 }
1507
1508 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1509 // default_methods also uses this without the ordering for fast find_method
1510 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1511 int length = methods->length();
1512 if (length > 1) {
1513 {
1514 NoSafepointVerifier nsv;
1515 QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1516 }
1517 // Reset method ordering
1518 if (set_idnums) {
1519 for (int i = 0; i < length; i++) {
1520 Method* m = methods->at(i);
1521 m->set_method_idnum(i);
1522 m->set_orig_method_idnum(i);
1523 }
1524 }
1525 }
1526 }
1527
1528 //-----------------------------------------------------------------------------------
1529 // Non-product code unless JVM/TI needs it
1530
1531 #if !defined(PRODUCT) || INCLUDE_JVMTI
1532 class SignatureTypePrinter : public SignatureTypeNames {
1533 private:
1534 outputStream* _st;
1535 bool _use_separator;
1536
1537 void type_name(const char* name) {
1538 if (_use_separator) _st->print(", ");
1539 _st->print("%s", name);
1540 _use_separator = true;
1541 }
1542
1543 public:
1544 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1545 _st = st;
1546 _use_separator = false;
1547 }
1548
1549 void print_parameters() { _use_separator = false; iterate_parameters(); }
1550 void print_returntype() { _use_separator = false; iterate_returntype(); }
1551 };
1552
1553
1554 void Method::print_name(outputStream* st) {
1555 Thread *thread = Thread::current();
1556 ResourceMark rm(thread);
1557 st->print("%s ", is_static() ? "static" : "virtual");
1558 if (WizardMode) {
1559 st->print("%s.", method_holder()->internal_name());
1560 name()->print_symbol_on(st);
1561 signature()->print_symbol_on(st);
1562 } else {
1563 SignatureTypePrinter sig(signature(), st);
1564 sig.print_returntype();
1565 st->print(" %s.", method_holder()->internal_name());
1566 name()->print_symbol_on(st);
1567 st->print("(");
1568 sig.print_parameters();
1569 st->print(")");
1570 }
1571 }
1572 #endif // !PRODUCT || INCLUDE_JVMTI
1573
1574
1575 void Method::print_codes_on(outputStream* st) const {
1576 print_codes_on(0, code_size(), st);
1577 }
1578
1579 void Method::print_codes_on(int from, int to, outputStream* st) const {
1580 Thread *thread = Thread::current();
1581 ResourceMark rm(thread);
1582 methodHandle mh (thread, (Method*)this);
1583 BytecodeStream s(mh);
1584 s.set_interval(from, to);
1585 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1586 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1587 }
1588
1589
1590 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1591 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1592 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1593 // as end-of-stream terminator.
1594
1595 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1596 // bci and line number does not compress into single byte.
1597 // Write out escape character and use regular compression for bci and line number.
1598 write_byte((jubyte)0xFF);
1599 write_signed_int(bci_delta);
1600 write_signed_int(line_delta);
1601 }
1602
1603 // See comment in method.hpp which explains why this exists.
1604 #if defined(_M_AMD64) && _MSC_VER >= 1400
1605 #pragma optimize("", off)
1606 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1607 write_pair_inline(bci, line);
1608 }
1609 #pragma optimize("", on)
1610 #endif
1611
1612 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1613 _bci = 0;
1614 _line = 0;
1615 };
1616
1617
1618 bool CompressedLineNumberReadStream::read_pair() {
1619 jubyte next = read_byte();
1620 // Check for terminator
1621 if (next == 0) return false;
1622 if (next == 0xFF) {
1623 // Escape character, regular compression used
1624 _bci += read_signed_int();
1625 _line += read_signed_int();
1626 } else {
1627 // Single byte compression used
1628 _bci += next >> 3;
1629 _line += next & 0x7;
1630 }
1631 return true;
1632 }
1633
1634 #if INCLUDE_JVMTI
1635
1636 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1637 BreakpointInfo* bp = method_holder()->breakpoints();
1638 for (; bp != NULL; bp = bp->next()) {
1639 if (bp->match(this, bci)) {
1640 return bp->orig_bytecode();
1641 }
1642 }
1643 {
1644 ResourceMark rm;
1645 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1646 }
1647 return Bytecodes::_shouldnotreachhere;
1648 }
1649
1650 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1651 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1652 BreakpointInfo* bp = method_holder()->breakpoints();
1653 for (; bp != NULL; bp = bp->next()) {
1654 if (bp->match(this, bci)) {
1655 bp->set_orig_bytecode(code);
1656 // and continue, in case there is more than one
1657 }
1658 }
1659 }
1660
1661 void Method::set_breakpoint(int bci) {
1662 InstanceKlass* ik = method_holder();
1663 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1664 bp->set_next(ik->breakpoints());
1665 ik->set_breakpoints(bp);
1666 // do this last:
1667 bp->set(this);
1668 }
1669
1670 static void clear_matches(Method* m, int bci) {
1671 InstanceKlass* ik = m->method_holder();
1672 BreakpointInfo* prev_bp = NULL;
1673 BreakpointInfo* next_bp;
1674 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1675 next_bp = bp->next();
1676 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1677 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1678 // do this first:
1679 bp->clear(m);
1680 // unhook it
1681 if (prev_bp != NULL)
1682 prev_bp->set_next(next_bp);
1683 else
1684 ik->set_breakpoints(next_bp);
1685 delete bp;
1686 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1687 // at same location. So we have multiple matching (method_index and bci)
1688 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1689 // breakpoint for clear_breakpoint request and keep all other method versions
1690 // BreakpointInfo for future clear_breakpoint request.
1691 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1692 // which is being called when class is unloaded. We delete all the Breakpoint
1693 // information for all versions of method. We may not correctly restore the original
1694 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1695 // so these methods won't be used anymore.
1696 if (bci >= 0) {
1697 break;
1698 }
1699 } else {
1700 // This one is a keeper.
1701 prev_bp = bp;
1702 }
1703 }
1704 }
1705
1706 void Method::clear_breakpoint(int bci) {
1707 assert(bci >= 0, "");
1708 clear_matches(this, bci);
1709 }
1710
1711 void Method::clear_all_breakpoints() {
1712 clear_matches(this, -1);
1713 }
1714
1715 #endif // INCLUDE_JVMTI
1716
1717 int Method::invocation_count() {
1718 MethodCounters *mcs = method_counters();
1719 if (TieredCompilation) {
1720 MethodData* const mdo = method_data();
1721 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1722 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1723 return InvocationCounter::count_limit;
1724 } else {
1725 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1726 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1727 }
1728 } else {
1729 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1730 }
1731 }
1732
1733 int Method::backedge_count() {
1734 MethodCounters *mcs = method_counters();
1735 if (TieredCompilation) {
1736 MethodData* const mdo = method_data();
1737 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1738 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1739 return InvocationCounter::count_limit;
1740 } else {
1741 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1742 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1743 }
1744 } else {
1745 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1746 }
1747 }
1748
1749 int Method::highest_comp_level() const {
1750 const MethodCounters* mcs = method_counters();
1751 if (mcs != NULL) {
1752 return mcs->highest_comp_level();
1753 } else {
1754 return CompLevel_none;
1755 }
1756 }
1757
1758 int Method::highest_osr_comp_level() const {
1759 const MethodCounters* mcs = method_counters();
1760 if (mcs != NULL) {
1761 return mcs->highest_osr_comp_level();
1762 } else {
1763 return CompLevel_none;
1764 }
1765 }
1766
1767 void Method::set_highest_comp_level(int level) {
1768 MethodCounters* mcs = method_counters();
1769 if (mcs != NULL) {
1770 mcs->set_highest_comp_level(level);
1771 }
1772 }
1773
1774 void Method::set_highest_osr_comp_level(int level) {
1775 MethodCounters* mcs = method_counters();
1776 if (mcs != NULL) {
1777 mcs->set_highest_osr_comp_level(level);
1778 }
1779 }
1780
1781 #if INCLUDE_JVMTI
1782
1783 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1784 _bci = bci;
1785 _name_index = m->name_index();
1786 _signature_index = m->signature_index();
1787 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1788 if (_orig_bytecode == Bytecodes::_breakpoint)
1789 _orig_bytecode = m->orig_bytecode_at(_bci);
1790 _next = NULL;
1791 }
1792
1793 void BreakpointInfo::set(Method* method) {
1794 #ifdef ASSERT
1795 {
1796 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1797 if (code == Bytecodes::_breakpoint)
1798 code = method->orig_bytecode_at(_bci);
1799 assert(orig_bytecode() == code, "original bytecode must be the same");
1800 }
1801 #endif
1802 Thread *thread = Thread::current();
1803 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1804 method->incr_number_of_breakpoints(thread);
1805 SystemDictionary::notice_modification();
1806 {
1807 // Deoptimize all dependents on this method
1808 HandleMark hm(thread);
1809 methodHandle mh(thread, method);
1810 CodeCache::flush_dependents_on_method(mh);
1811 }
1812 }
1813
1814 void BreakpointInfo::clear(Method* method) {
1815 *method->bcp_from(_bci) = orig_bytecode();
1816 assert(method->number_of_breakpoints() > 0, "must not go negative");
1817 method->decr_number_of_breakpoints(Thread::current());
1818 }
1819
1820 #endif // INCLUDE_JVMTI
1821
1822 // jmethodID handling
1823
1824 // This is a block allocating object, sort of like JNIHandleBlock, only a
1825 // lot simpler.
1826 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1827 // never get rid of it.
1828
1829 static const int min_block_size = 8;
1830
1831 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1832 friend class JNIMethodBlock;
1833 Method** _methods;
1834 int _number_of_methods;
1835 int _top;
1836 JNIMethodBlockNode* _next;
1837
1838 public:
1839
1840 JNIMethodBlockNode(int num_methods = min_block_size);
1841
1842 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1843
1844 void ensure_methods(int num_addl_methods) {
1845 if (_top < _number_of_methods) {
1846 num_addl_methods -= _number_of_methods - _top;
1847 if (num_addl_methods <= 0) {
1848 return;
1849 }
1850 }
1851 if (_next == NULL) {
1852 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1853 } else {
1854 _next->ensure_methods(num_addl_methods);
1855 }
1856 }
1857 };
1858
1859 class JNIMethodBlock : public CHeapObj<mtClass> {
1860 JNIMethodBlockNode _head;
1861 JNIMethodBlockNode *_last_free;
1862 public:
1863 static Method* const _free_method;
1864
1865 JNIMethodBlock(int initial_capacity = min_block_size)
1866 : _head(initial_capacity), _last_free(&_head) {}
1867
1868 void ensure_methods(int num_addl_methods) {
1869 _last_free->ensure_methods(num_addl_methods);
1870 }
1871
1872 Method** add_method(Method* m) {
1873 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1874 if (b->_top < b->_number_of_methods) {
1875 // top points to the next free entry.
1876 int i = b->_top;
1877 b->_methods[i] = m;
1878 b->_top++;
1879 _last_free = b;
1880 return &(b->_methods[i]);
1881 } else if (b->_top == b->_number_of_methods) {
1882 // if the next free entry ran off the block see if there's a free entry
1883 for (int i = 0; i < b->_number_of_methods; i++) {
1884 if (b->_methods[i] == _free_method) {
1885 b->_methods[i] = m;
1886 _last_free = b;
1887 return &(b->_methods[i]);
1888 }
1889 }
1890 // Only check each block once for frees. They're very unlikely.
1891 // Increment top past the end of the block.
1892 b->_top++;
1893 }
1894 // need to allocate a next block.
1895 if (b->_next == NULL) {
1896 b->_next = _last_free = new JNIMethodBlockNode();
1897 }
1898 }
1899 guarantee(false, "Should always allocate a free block");
1900 return NULL;
1901 }
1902
1903 bool contains(Method** m) {
1904 if (m == NULL) return false;
1905 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1906 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
1907 // This is a bit of extra checking, for two reasons. One is
1908 // that contains() deals with pointers that are passed in by
1909 // JNI code, so making sure that the pointer is aligned
1910 // correctly is valuable. The other is that <= and > are
1911 // technically not defined on pointers, so the if guard can
1912 // pass spuriously; no modern compiler is likely to make that
1913 // a problem, though (and if one did, the guard could also
1914 // fail spuriously, which would be bad).
1915 ptrdiff_t idx = m - b->_methods;
1916 if (b->_methods + idx == m) {
1917 return true;
1918 }
1919 }
1920 }
1921 return false; // not found
1922 }
1923
1924 // Doesn't really destroy it, just marks it as free so it can be reused.
1925 void destroy_method(Method** m) {
1926 #ifdef ASSERT
1927 assert(contains(m), "should be a methodID");
1928 #endif // ASSERT
1929 *m = _free_method;
1930 }
1931
1932 // During class unloading the methods are cleared, which is different
1933 // than freed.
1934 void clear_all_methods() {
1935 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1936 for (int i = 0; i< b->_number_of_methods; i++) {
1937 b->_methods[i] = NULL;
1938 }
1939 }
1940 }
1941 #ifndef PRODUCT
1942 int count_methods() {
1943 // count all allocated methods
1944 int count = 0;
1945 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1946 for (int i = 0; i< b->_number_of_methods; i++) {
1947 if (b->_methods[i] != _free_method) count++;
1948 }
1949 }
1950 return count;
1951 }
1952 #endif // PRODUCT
1953 };
1954
1955 // Something that can't be mistaken for an address or a markOop
1956 Method* const JNIMethodBlock::_free_method = (Method*)55;
1957
1958 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
1959 _number_of_methods = MAX2(num_methods, min_block_size);
1960 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
1961 for (int i = 0; i < _number_of_methods; i++) {
1962 _methods[i] = JNIMethodBlock::_free_method;
1963 }
1964 }
1965
1966 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
1967 ClassLoaderData* cld = loader_data;
1968 if (!SafepointSynchronize::is_at_safepoint()) {
1969 // Have to add jmethod_ids() to class loader data thread-safely.
1970 // Also have to add the method to the list safely, which the cld lock
1971 // protects as well.
1972 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
1973 if (cld->jmethod_ids() == NULL) {
1974 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
1975 } else {
1976 cld->jmethod_ids()->ensure_methods(capacity);
1977 }
1978 } else {
1979 // At safepoint, we are single threaded and can set this.
1980 if (cld->jmethod_ids() == NULL) {
1981 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
1982 } else {
1983 cld->jmethod_ids()->ensure_methods(capacity);
1984 }
1985 }
1986 }
1987
1988 // Add a method id to the jmethod_ids
1989 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
1990 ClassLoaderData* cld = loader_data;
1991
1992 if (!SafepointSynchronize::is_at_safepoint()) {
1993 // Have to add jmethod_ids() to class loader data thread-safely.
1994 // Also have to add the method to the list safely, which the cld lock
1995 // protects as well.
1996 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
1997 if (cld->jmethod_ids() == NULL) {
1998 cld->set_jmethod_ids(new JNIMethodBlock());
1999 }
2000 // jmethodID is a pointer to Method*
2001 return (jmethodID)cld->jmethod_ids()->add_method(m);
2002 } else {
2003 // At safepoint, we are single threaded and can set this.
2004 if (cld->jmethod_ids() == NULL) {
2005 cld->set_jmethod_ids(new JNIMethodBlock());
2006 }
2007 // jmethodID is a pointer to Method*
2008 return (jmethodID)cld->jmethod_ids()->add_method(m);
2009 }
2010 }
2011
2012 // Mark a jmethodID as free. This is called when there is a data race in
2013 // InstanceKlass while creating the jmethodID cache.
2014 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2015 ClassLoaderData* cld = loader_data;
2016 Method** ptr = (Method**)m;
2017 assert(cld->jmethod_ids() != NULL, "should have method handles");
2018 cld->jmethod_ids()->destroy_method(ptr);
2019 }
2020
2021 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2022 // Can't assert the method_holder is the same because the new method has the
2023 // scratch method holder.
2024 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2025 == new_method->method_holder()->class_loader(),
2026 "changing to a different class loader");
2027 // Just change the method in place, jmethodID pointer doesn't change.
2028 *((Method**)jmid) = new_method;
2029 }
2030
2031 bool Method::is_method_id(jmethodID mid) {
2032 Method* m = resolve_jmethod_id(mid);
2033 assert(m != NULL, "should be called with non-null method");
2034 InstanceKlass* ik = m->method_holder();
2035 ClassLoaderData* cld = ik->class_loader_data();
2036 if (cld->jmethod_ids() == NULL) return false;
2037 return (cld->jmethod_ids()->contains((Method**)mid));
2038 }
2039
2040 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2041 if (mid == NULL) return NULL;
2042 Method* o = resolve_jmethod_id(mid);
2043 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2044 return NULL;
2045 }
2046 return o;
2047 };
2048
2049 void Method::set_on_stack(const bool value) {
2050 // Set both the method itself and its constant pool. The constant pool
2051 // on stack means some method referring to it is also on the stack.
2052 constants()->set_on_stack(value);
2053
2054 bool already_set = on_stack();
2055 _access_flags.set_on_stack(value);
2056 if (value && !already_set) {
2057 MetadataOnStackMark::record(this);
2058 }
2059 }
2060
2061 // Called when the class loader is unloaded to make all methods weak.
2062 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2063 loader_data->jmethod_ids()->clear_all_methods();
2064 }
2065
2066 bool Method::has_method_vptr(const void* ptr) {
2067 Method m;
2068 // This assumes that the vtbl pointer is the first word of a C++ object.
2069 // This assumption is also in universe.cpp patch_klass_vtble
2070 return dereference_vptr(&m) == dereference_vptr(ptr);
2071 }
2072
2073 // Check that this pointer is valid by checking that the vtbl pointer matches
2074 bool Method::is_valid_method() const {
2075 if (this == NULL) {
2076 return false;
2077 } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2078 // Quick sanity check on pointer.
2079 return false;
2080 } else if (!is_metaspace_object()) {
2081 return false;
2082 } else {
2083 return has_method_vptr((const void*)this);
2084 }
2085 }
2086
2087 #ifndef PRODUCT
2088 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
2089 out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2090 }
2091 #endif // PRODUCT
2092
2093
2094 // Printing
2095
2096 #ifndef PRODUCT
2097
2098 void Method::print_on(outputStream* st) const {
2099 ResourceMark rm;
2100 assert(is_method(), "must be method");
2101 st->print_cr("%s", internal_name());
2102 // get the effect of PrintOopAddress, always, for methods:
2103 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2104 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2105 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2106 constants()->print_value_on(st); st->cr();
2107 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2108 st->print (" - name: "); name()->print_value_on(st); st->cr();
2109 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2110 st->print_cr(" - max stack: %d", max_stack());
2111 st->print_cr(" - max locals: %d", max_locals());
2112 st->print_cr(" - size of params: %d", size_of_parameters());
2113 st->print_cr(" - method size: %d", method_size());
2114 if (intrinsic_id() != vmIntrinsics::_none)
2115 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2116 if (highest_comp_level() != CompLevel_none)
2117 st->print_cr(" - highest level: %d", highest_comp_level());
2118 st->print_cr(" - vtable index: %d", _vtable_index);
2119 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2120 st->print( " - adapters: ");
2121 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2122 if (a == NULL)
2123 st->print_cr(INTPTR_FORMAT, p2i(a));
2124 else
2125 a->print_adapter_on(st);
2126 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2127 st->print_cr(" - code size: %d", code_size());
2128 if (code_size() != 0) {
2129 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2130 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2131 }
2132 if (method_data() != NULL) {
2133 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2134 }
2135 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2136 if (checked_exceptions_length() > 0) {
2137 CheckedExceptionElement* table = checked_exceptions_start();
2138 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2139 if (Verbose) {
2140 for (int i = 0; i < checked_exceptions_length(); i++) {
2141 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2142 }
2143 }
2144 }
2145 if (has_linenumber_table()) {
2146 u_char* table = compressed_linenumber_table();
2147 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2148 if (Verbose) {
2149 CompressedLineNumberReadStream stream(table);
2150 while (stream.read_pair()) {
2151 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2152 }
2153 }
2154 }
2155 st->print_cr(" - localvar length: %d", localvariable_table_length());
2156 if (localvariable_table_length() > 0) {
2157 LocalVariableTableElement* table = localvariable_table_start();
2158 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2159 if (Verbose) {
2160 for (int i = 0; i < localvariable_table_length(); i++) {
2161 int bci = table[i].start_bci;
2162 int len = table[i].length;
2163 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2164 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2165 int slot = table[i].slot;
2166 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2167 }
2168 }
2169 }
2170 if (code() != NULL) {
2171 st->print (" - compiled code: ");
2172 code()->print_value_on(st);
2173 }
2174 if (is_native()) {
2175 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2176 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2177 }
2178 }
2179
2180 void Method::print_linkage_flags(outputStream* st) {
2181 access_flags().print_on(st);
2182 if (is_default_method()) {
2183 st->print("default ");
2184 }
2185 if (is_overpass()) {
2186 st->print("overpass ");
2187 }
2188 }
2189 #endif //PRODUCT
2190
2191 void Method::print_value_on(outputStream* st) const {
2192 assert(is_method(), "must be method");
2193 st->print("%s", internal_name());
2194 print_address_on(st);
2195 st->print(" ");
2196 name()->print_value_on(st);
2197 st->print(" ");
2198 signature()->print_value_on(st);
2199 st->print(" in ");
2200 method_holder()->print_value_on(st);
2201 if (WizardMode) st->print("#%d", _vtable_index);
2202 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2203 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2204 }
2205
2206 #if INCLUDE_SERVICES
2207 // Size Statistics
2208 void Method::collect_statistics(KlassSizeStats *sz) const {
2209 int mysize = sz->count(this);
2210 sz->_method_bytes += mysize;
2211 sz->_method_all_bytes += mysize;
2212 sz->_rw_bytes += mysize;
2213
2214 if (constMethod()) {
2215 constMethod()->collect_statistics(sz);
2216 }
2217 if (method_data()) {
2218 method_data()->collect_statistics(sz);
2219 }
2220 }
2221 #endif // INCLUDE_SERVICES
2222
2223 // LogTouchedMethods and PrintTouchedMethods
2224
2225 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2226 // the Method may be garbage collected. Let's roll our own hash table.
2227 class TouchedMethodRecord : CHeapObj<mtTracing> {
2228 public:
2229 // It's OK to store Symbols here because they will NOT be GC'ed if
2230 // LogTouchedMethods is enabled.
2231 TouchedMethodRecord* _next;
2232 Symbol* _class_name;
2233 Symbol* _method_name;
2234 Symbol* _method_signature;
2235 };
2236
2237 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2238 static TouchedMethodRecord** _touched_method_table = NULL;
2239
2240 void Method::log_touched(TRAPS) {
2241
2242 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2243 Symbol* my_class = klass_name();
2244 Symbol* my_name = name();
2245 Symbol* my_sig = signature();
2246
2247 unsigned int hash = my_class->identity_hash() +
2248 my_name->identity_hash() +
2249 my_sig->identity_hash();
2250 juint index = juint(hash) % table_size;
2251
2252 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2253 if (_touched_method_table == NULL) {
2254 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2255 mtTracing, CURRENT_PC);
2256 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2257 }
2258
2259 TouchedMethodRecord* ptr = _touched_method_table[index];
2260 while (ptr) {
2261 if (ptr->_class_name == my_class &&
2262 ptr->_method_name == my_name &&
2263 ptr->_method_signature == my_sig) {
2264 return;
2265 }
2266 if (ptr->_next == NULL) break;
2267 ptr = ptr->_next;
2268 }
2269 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2270 my_class->set_permanent(); // prevent reclaimed by GC
2271 my_name->set_permanent();
2272 my_sig->set_permanent();
2273 nptr->_class_name = my_class;
2274 nptr->_method_name = my_name;
2275 nptr->_method_signature = my_sig;
2276 nptr->_next = NULL;
2277
2278 if (ptr == NULL) {
2279 // first
2280 _touched_method_table[index] = nptr;
2281 } else {
2282 ptr->_next = nptr;
2283 }
2284 }
2285
2286 void Method::print_touched_methods(outputStream* out) {
2287 MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2288 out->print_cr("# Method::print_touched_methods version 1");
2289 if (_touched_method_table) {
2290 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2291 TouchedMethodRecord* ptr = _touched_method_table[i];
2292 while(ptr) {
2293 ptr->_class_name->print_symbol_on(out); out->print(".");
2294 ptr->_method_name->print_symbol_on(out); out->print(":");
2295 ptr->_method_signature->print_symbol_on(out); out->cr();
2296 ptr = ptr->_next;
2297 }
2298 }
2299 }
2300 }
2301
2302 // Verification
2303
2304 void Method::verify_on(outputStream* st) {
2305 guarantee(is_method(), "object must be method");
2306 guarantee(constants()->is_constantPool(), "should be constant pool");
2307 guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2308 MethodData* md = method_data();
2309 guarantee(md == NULL ||
2310 md->is_methodData(), "should be method data");
2311 }