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