1 /*
2 * Copyright (c) 1997, 2019, 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/classLoaderDataGraph.hpp"
27 #include "classfile/metadataOnStackMark.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "code/codeCache.hpp"
30 #include "code/debugInfoRec.hpp"
31 #include "gc/shared/collectedHeap.inline.hpp"
32 #include "interpreter/bytecodeStream.hpp"
33 #include "interpreter/bytecodeTracer.hpp"
34 #include "interpreter/bytecodes.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "interpreter/oopMapCache.hpp"
37 #include "memory/allocation.inline.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 "memory/universe.hpp"
45 #include "oops/constMethod.hpp"
46 #include "oops/constantPool.hpp"
47 #include "oops/method.inline.hpp"
48 #include "oops/methodData.hpp"
49 #include "oops/objArrayKlass.hpp"
50 #include "oops/objArrayOop.inline.hpp"
51 #include "oops/oop.inline.hpp"
52 #include "oops/symbol.hpp"
53 #include "prims/jvmtiExport.hpp"
54 #include "prims/methodHandles.hpp"
55 #include "prims/nativeLookup.hpp"
56 #include "runtime/arguments.hpp"
57 #include "runtime/compilationPolicy.hpp"
58 #include "runtime/frame.inline.hpp"
59 #include "runtime/handles.inline.hpp"
60 #include "runtime/init.hpp"
61 #include "runtime/orderAccess.hpp"
62 #include "runtime/relocator.hpp"
63 #include "runtime/safepointVerifiers.hpp"
64 #include "runtime/sharedRuntime.hpp"
65 #include "runtime/signature.hpp"
66 #include "utilities/align.hpp"
67 #include "utilities/quickSort.hpp"
68 #include "utilities/vmError.hpp"
69 #include "utilities/xmlstream.hpp"
70
71 // Implementation of Method
72
73 Method* Method::allocate(ClassLoaderData* loader_data,
74 int byte_code_size,
75 AccessFlags access_flags,
76 InlineTableSizes* sizes,
77 ConstMethod::MethodType method_type,
78 TRAPS) {
79 assert(!access_flags.is_native() || byte_code_size == 0,
80 "native methods should not contain byte codes");
81 ConstMethod* cm = ConstMethod::allocate(loader_data,
82 byte_code_size,
83 sizes,
84 method_type,
85 CHECK_NULL);
86 int size = Method::size(access_flags.is_native());
87 return new (loader_data, size, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
88 }
89
90 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
91 NoSafepointVerifier no_safepoint;
92 set_constMethod(xconst);
93 set_access_flags(access_flags);
94 set_intrinsic_id(vmIntrinsics::_none);
95 set_force_inline(false);
96 set_hidden(false);
97 set_dont_inline(false);
98 set_has_injected_profile(false);
99 set_method_data(NULL);
100 clear_method_counters();
101 set_vtable_index(Method::garbage_vtable_index);
102
103 // Fix and bury in Method*
104 set_interpreter_entry(NULL); // sets i2i entry and from_int
105 set_adapter_entry(NULL);
106 Method::clear_code(); // from_c/from_i get set to c2i/i2i
107
108 if (access_flags.is_native()) {
109 clear_native_function();
110 set_signature_handler(NULL);
111 }
112
113 NOT_PRODUCT(set_compiled_invocation_count(0);)
114 }
115
116 // Release Method*. The nmethod will be gone when we get here because
117 // we've walked the code cache.
118 void Method::deallocate_contents(ClassLoaderData* loader_data) {
119 MetadataFactory::free_metadata(loader_data, constMethod());
120 set_constMethod(NULL);
121 #if INCLUDE_JVMCI
122 if (method_data()) {
123 FailedSpeculation::free_failed_speculations(method_data()->get_failed_speculations_address());
124 }
125 #endif
126 MetadataFactory::free_metadata(loader_data, method_data());
127 set_method_data(NULL);
128 MetadataFactory::free_metadata(loader_data, method_counters());
129 clear_method_counters();
130 // The nmethod will be gone when we get here.
131 if (code() != NULL) _code = NULL;
132 }
133
134 address Method::get_i2c_entry() {
135 assert(adapter() != NULL, "must have");
136 return adapter()->get_i2c_entry();
137 }
138
139 address Method::get_c2i_entry() {
140 assert(adapter() != NULL, "must have");
141 return adapter()->get_c2i_entry();
142 }
143
144 address Method::get_c2i_unverified_entry() {
145 assert(adapter() != NULL, "must have");
146 return adapter()->get_c2i_unverified_entry();
147 }
148
149 char* Method::name_and_sig_as_C_string() const {
150 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
151 }
152
153 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
154 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
155 }
156
157 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
158 const char* klass_name = klass->external_name();
159 int klass_name_len = (int)strlen(klass_name);
160 int method_name_len = method_name->utf8_length();
161 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
162 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
163 strcpy(dest, klass_name);
164 dest[klass_name_len] = '.';
165 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
166 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
167 dest[len] = 0;
168 return dest;
169 }
170
171 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
172 Symbol* klass_name = klass->name();
173 klass_name->as_klass_external_name(buf, size);
174 int len = (int)strlen(buf);
175
176 if (len < size - 1) {
177 buf[len++] = '.';
178
179 method_name->as_C_string(&(buf[len]), size - len);
180 len = (int)strlen(buf);
181
182 signature->as_C_string(&(buf[len]), size - len);
183 }
184
185 return buf;
186 }
187
188 const char* Method::external_name() const {
189 return external_name(constants()->pool_holder(), name(), signature());
190 }
191
192 void Method::print_external_name(outputStream *os) const {
193 print_external_name(os, constants()->pool_holder(), name(), signature());
194 }
195
196 const char* Method::external_name(Klass* klass, Symbol* method_name, Symbol* signature) {
197 stringStream ss;
198 print_external_name(&ss, klass, method_name, signature);
199 return ss.as_string();
200 }
201
202 void Method::print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature) {
203 signature->print_as_signature_external_return_type(os);
204 os->print(" %s.%s(", klass->external_name(), method_name->as_C_string());
205 signature->print_as_signature_external_parameters(os);
206 os->print(")");
207 }
208
209 int Method::fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS) {
210 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
211 // access exception table
212 ExceptionTable table(mh());
213 int length = table.length();
214 // iterate through all entries sequentially
215 constantPoolHandle pool(THREAD, mh->constants());
216 for (int i = 0; i < length; i ++) {
217 //reacquire the table in case a GC happened
218 ExceptionTable table(mh());
219 int beg_bci = table.start_pc(i);
220 int end_bci = table.end_pc(i);
221 assert(beg_bci <= end_bci, "inconsistent exception table");
222 if (beg_bci <= throw_bci && throw_bci < end_bci) {
223 // exception handler bci range covers throw_bci => investigate further
224 int handler_bci = table.handler_pc(i);
225 int klass_index = table.catch_type_index(i);
226 if (klass_index == 0) {
227 return handler_bci;
228 } else if (ex_klass == NULL) {
229 return handler_bci;
230 } else {
231 // we know the exception class => get the constraint class
232 // this may require loading of the constraint class; if verification
233 // fails or some other exception occurs, return handler_bci
234 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
235 assert(k != NULL, "klass not loaded");
236 if (ex_klass->is_subtype_of(k)) {
237 return handler_bci;
238 }
239 }
240 }
241 }
242
243 return -1;
244 }
245
246 void Method::mask_for(int bci, InterpreterOopMap* mask) {
247 methodHandle h_this(Thread::current(), this);
248 // Only GC uses the OopMapCache during thread stack root scanning
249 // any other uses generate an oopmap but do not save it in the cache.
250 if (Universe::heap()->is_gc_active()) {
251 method_holder()->mask_for(h_this, bci, mask);
252 } else {
253 OopMapCache::compute_one_oop_map(h_this, bci, mask);
254 }
255 return;
256 }
257
258
259 int Method::bci_from(address bcp) const {
260 if (is_native() && bcp == 0) {
261 return 0;
262 }
263 #ifdef ASSERT
264 {
265 ResourceMark rm;
266 assert(is_native() && bcp == code_base() || contains(bcp) || VMError::is_error_reported(),
267 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
268 p2i(bcp), name_and_sig_as_C_string());
269 }
270 #endif
271 return bcp - code_base();
272 }
273
274
275 int Method::validate_bci(int bci) const {
276 return (bci == 0 || bci < code_size()) ? bci : -1;
277 }
278
279 // Return bci if it appears to be a valid bcp
280 // Return -1 otherwise.
281 // Used by profiling code, when invalid data is a possibility.
282 // The caller is responsible for validating the Method* itself.
283 int Method::validate_bci_from_bcp(address bcp) const {
284 // keep bci as -1 if not a valid bci
285 int bci = -1;
286 if (bcp == 0 || bcp == code_base()) {
287 // code_size() may return 0 and we allow 0 here
288 // the method may be native
289 bci = 0;
290 } else if (contains(bcp)) {
291 bci = bcp - code_base();
292 }
293 // Assert that if we have dodged any asserts, bci is negative.
294 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
295 return bci;
296 }
297
298 address Method::bcp_from(int bci) const {
299 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
300 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
301 address bcp = code_base() + bci;
302 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
303 return bcp;
304 }
305
306 address Method::bcp_from(address bcp) const {
307 if (is_native() && bcp == NULL) {
308 return code_base();
309 } else {
310 return bcp;
311 }
312 }
313
314 int Method::size(bool is_native) {
315 // If native, then include pointers for native_function and signature_handler
316 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
317 int extra_words = align_up(extra_bytes, BytesPerWord) / BytesPerWord;
318 return align_metadata_size(header_size() + extra_words);
319 }
320
321
322 Symbol* Method::klass_name() const {
323 return method_holder()->name();
324 }
325
326
327 void Method::metaspace_pointers_do(MetaspaceClosure* it) {
328 log_trace(cds)("Iter(Method): %p", this);
329
330 it->push(&_constMethod);
331 it->push(&_method_data);
332 it->push(&_method_counters);
333 }
334
335 // Attempt to return method oop to original state. Clear any pointers
336 // (to objects outside the shared spaces). We won't be able to predict
337 // where they should point in a new JVM. Further initialize some
338 // entries now in order allow them to be write protected later.
339
340 void Method::remove_unshareable_info() {
341 unlink_method();
342 }
343
344 void Method::set_vtable_index(int index) {
345 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
346 // At runtime initialize_vtable is rerun as part of link_class_impl()
347 // for a shared class loaded by the non-boot loader to obtain the loader
348 // constraints based on the runtime classloaders' context.
349 return; // don't write into the shared class
350 } else {
351 _vtable_index = index;
352 }
353 }
354
355 void Method::set_itable_index(int index) {
356 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
357 // At runtime initialize_itable is rerun as part of link_class_impl()
358 // for a shared class loaded by the non-boot loader to obtain the loader
359 // constraints based on the runtime classloaders' context. The dumptime
360 // itable index should be the same as the runtime index.
361 assert(_vtable_index == itable_index_max - index,
362 "archived itable index is different from runtime index");
363 return; // don’t write into the shared class
364 } else {
365 _vtable_index = itable_index_max - index;
366 }
367 assert(valid_itable_index(), "");
368 }
369
370
371
372 bool Method::was_executed_more_than(int n) {
373 // Invocation counter is reset when the Method* is compiled.
374 // If the method has compiled code we therefore assume it has
375 // be excuted more than n times.
376 if (is_accessor() || is_empty_method() || (code() != NULL)) {
377 // interpreter doesn't bump invocation counter of trivial methods
378 // compiler does not bump invocation counter of compiled methods
379 return true;
380 }
381 else if ((method_counters() != NULL &&
382 method_counters()->invocation_counter()->carry()) ||
383 (method_data() != NULL &&
384 method_data()->invocation_counter()->carry())) {
385 // The carry bit is set when the counter overflows and causes
386 // a compilation to occur. We don't know how many times
387 // the counter has been reset, so we simply assume it has
388 // been executed more than n times.
389 return true;
390 } else {
391 return invocation_count() > n;
392 }
393 }
394
395 void Method::print_invocation_count() {
396 if (is_static()) tty->print("static ");
397 if (is_final()) tty->print("final ");
398 if (is_synchronized()) tty->print("synchronized ");
399 if (is_native()) tty->print("native ");
400 tty->print("%s::", method_holder()->external_name());
401 name()->print_symbol_on(tty);
402 signature()->print_symbol_on(tty);
403
404 if (WizardMode) {
405 // dump the size of the byte codes
406 tty->print(" {%d}", code_size());
407 }
408 tty->cr();
409
410 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
411 tty->print_cr (" invocation_counter: %8d ", invocation_count());
412 tty->print_cr (" backedge_counter: %8d ", backedge_count());
413 #ifndef PRODUCT
414 if (CountCompiledCalls) {
415 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
416 }
417 #endif
418 }
419
420 // Build a MethodData* object to hold information about this method
421 // collected in the interpreter.
422 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
423 // Do not profile the method if metaspace has hit an OOM previously
424 // allocating profiling data. Callers clear pending exception so don't
425 // add one here.
426 if (ClassLoaderDataGraph::has_metaspace_oom()) {
427 return;
428 }
429
430 // Grab a lock here to prevent multiple
431 // MethodData*s from being created.
432 MutexLocker ml(MethodData_lock, THREAD);
433 if (method->method_data() == NULL) {
434 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
435 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
436 if (HAS_PENDING_EXCEPTION) {
437 CompileBroker::log_metaspace_failure();
438 ClassLoaderDataGraph::set_metaspace_oom(true);
439 return; // return the exception (which is cleared)
440 }
441
442 method->set_method_data(method_data);
443 if (PrintMethodData && (Verbose || WizardMode)) {
444 ResourceMark rm(THREAD);
445 tty->print("build_interpreter_method_data for ");
446 method->print_name(tty);
447 tty->cr();
448 // At the end of the run, the MDO, full of data, will be dumped.
449 }
450 }
451 }
452
453 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
454 // Do not profile the method if metaspace has hit an OOM previously
455 if (ClassLoaderDataGraph::has_metaspace_oom()) {
456 return NULL;
457 }
458
459 methodHandle mh(m);
460 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
461 if (HAS_PENDING_EXCEPTION) {
462 CompileBroker::log_metaspace_failure();
463 ClassLoaderDataGraph::set_metaspace_oom(true);
464 return NULL; // return the exception (which is cleared)
465 }
466 if (!mh->init_method_counters(counters)) {
467 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
468 }
469
470 if (LogTouchedMethods) {
471 mh->log_touched(CHECK_NULL);
472 }
473
474 return mh->method_counters();
475 }
476
477 bool Method::init_method_counters(MethodCounters* counters) {
478 // Try to install a pointer to MethodCounters, return true on success.
479 return Atomic::replace_if_null(counters, &_method_counters);
480 }
481
482 int Method::extra_stack_words() {
483 // not an inline function, to avoid a header dependency on Interpreter
484 return extra_stack_entries() * Interpreter::stackElementSize;
485 }
486
487
488 void Method::compute_size_of_parameters(Thread *thread) {
489 ArgumentSizeComputer asc(signature());
490 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
491 }
492
493 BasicType Method::result_type() const {
494 ResultTypeFinder rtf(signature());
495 return rtf.type();
496 }
497
498
499 bool Method::is_empty_method() const {
500 return code_size() == 1
501 && *code_base() == Bytecodes::_return;
502 }
503
504
505 bool Method::is_vanilla_constructor() const {
506 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
507 // which only calls the superclass vanilla constructor and possibly does stores of
508 // zero constants to local fields:
509 //
510 // aload_0
511 // invokespecial
512 // indexbyte1
513 // indexbyte2
514 //
515 // followed by an (optional) sequence of:
516 //
517 // aload_0
518 // aconst_null / iconst_0 / fconst_0 / dconst_0
519 // putfield
520 // indexbyte1
521 // indexbyte2
522 //
523 // followed by:
524 //
525 // return
526
527 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
528 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
529 int size = code_size();
530 // Check if size match
531 if (size == 0 || size % 5 != 0) return false;
532 address cb = code_base();
533 int last = size - 1;
534 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
535 // Does not call superclass default constructor
536 return false;
537 }
538 // Check optional sequence
539 for (int i = 4; i < last; i += 5) {
540 if (cb[i] != Bytecodes::_aload_0) return false;
541 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
542 if (cb[i+2] != Bytecodes::_putfield) return false;
543 }
544 return true;
545 }
546
547
548 bool Method::compute_has_loops_flag() {
549 BytecodeStream bcs(this);
550 Bytecodes::Code bc;
551
552 while ((bc = bcs.next()) >= 0) {
553 switch( bc ) {
554 case Bytecodes::_ifeq:
555 case Bytecodes::_ifnull:
556 case Bytecodes::_iflt:
557 case Bytecodes::_ifle:
558 case Bytecodes::_ifne:
559 case Bytecodes::_ifnonnull:
560 case Bytecodes::_ifgt:
561 case Bytecodes::_ifge:
562 case Bytecodes::_if_icmpeq:
563 case Bytecodes::_if_icmpne:
564 case Bytecodes::_if_icmplt:
565 case Bytecodes::_if_icmpgt:
566 case Bytecodes::_if_icmple:
567 case Bytecodes::_if_icmpge:
568 case Bytecodes::_if_acmpeq:
569 case Bytecodes::_if_acmpne:
570 case Bytecodes::_goto:
571 case Bytecodes::_jsr:
572 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
573 break;
574
575 case Bytecodes::_goto_w:
576 case Bytecodes::_jsr_w:
577 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
578 break;
579
580 default:
581 break;
582 }
583 }
584 _access_flags.set_loops_flag_init();
585 return _access_flags.has_loops();
586 }
587
588 bool Method::is_final_method(AccessFlags class_access_flags) const {
589 // or "does_not_require_vtable_entry"
590 // default method or overpass can occur, is not final (reuses vtable entry)
591 // private methods in classes get vtable entries for backward class compatibility.
592 if (is_overpass() || is_default_method()) return false;
593 return is_final() || class_access_flags.is_final();
594 }
595
596 bool Method::is_final_method() const {
597 return is_final_method(method_holder()->access_flags());
598 }
599
600 bool Method::is_default_method() const {
601 if (method_holder() != NULL &&
602 method_holder()->is_interface() &&
603 !is_abstract() && !is_private()) {
604 return true;
605 } else {
606 return false;
607 }
608 }
609
610 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
611 if (is_final_method(class_access_flags)) return true;
612 #ifdef ASSERT
613 ResourceMark rm;
614 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
615 if (class_access_flags.is_interface()) {
616 assert(is_nonv == is_static() || is_nonv == is_private(),
617 "nonvirtual unexpected for non-static, non-private: %s",
618 name_and_sig_as_C_string());
619 }
620 #endif
621 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
622 return vtable_index() == nonvirtual_vtable_index;
623 }
624
625 bool Method::can_be_statically_bound() const {
626 return can_be_statically_bound(method_holder()->access_flags());
627 }
628
629 bool Method::can_be_statically_bound(InstanceKlass* context) const {
630 return (method_holder() == context) && can_be_statically_bound();
631 }
632
633 bool Method::is_accessor() const {
634 return is_getter() || is_setter();
635 }
636
637 bool Method::is_getter() const {
638 if (code_size() != 5) return false;
639 if (size_of_parameters() != 1) return false;
640 if (java_code_at(0) != Bytecodes::_aload_0) return false;
641 if (java_code_at(1) != Bytecodes::_getfield) return false;
642 switch (java_code_at(4)) {
643 case Bytecodes::_ireturn:
644 case Bytecodes::_lreturn:
645 case Bytecodes::_freturn:
646 case Bytecodes::_dreturn:
647 case Bytecodes::_areturn:
648 break;
649 default:
650 return false;
651 }
652 return true;
653 }
654
655 bool Method::is_setter() const {
656 if (code_size() != 6) return false;
657 if (java_code_at(0) != Bytecodes::_aload_0) return false;
658 switch (java_code_at(1)) {
659 case Bytecodes::_iload_1:
660 case Bytecodes::_aload_1:
661 case Bytecodes::_fload_1:
662 if (size_of_parameters() != 2) return false;
663 break;
664 case Bytecodes::_dload_1:
665 case Bytecodes::_lload_1:
666 if (size_of_parameters() != 3) return false;
667 break;
668 default:
669 return false;
670 }
671 if (java_code_at(2) != Bytecodes::_putfield) return false;
672 if (java_code_at(5) != Bytecodes::_return) return false;
673 return true;
674 }
675
676 bool Method::is_constant_getter() const {
677 int last_index = code_size() - 1;
678 // Check if the first 1-3 bytecodes are a constant push
679 // and the last bytecode is a return.
680 return (2 <= code_size() && code_size() <= 4 &&
681 Bytecodes::is_const(java_code_at(0)) &&
682 Bytecodes::length_for(java_code_at(0)) == last_index &&
683 Bytecodes::is_return(java_code_at(last_index)));
684 }
685
686 bool Method::is_initializer() const {
687 return is_object_initializer() || is_static_initializer();
688 }
689
690 bool Method::has_valid_initializer_flags() const {
691 return (is_static() ||
692 method_holder()->major_version() < 51);
693 }
694
695 bool Method::is_static_initializer() const {
696 // For classfiles version 51 or greater, ensure that the clinit method is
697 // static. Non-static methods with the name "<clinit>" are not static
698 // initializers. (older classfiles exempted for backward compatibility)
699 return name() == vmSymbols::class_initializer_name() &&
700 has_valid_initializer_flags();
701 }
702
703 bool Method::is_object_initializer() const {
704 return name() == vmSymbols::object_initializer_name();
705 }
706
707 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
708 int length = method->checked_exceptions_length();
709 if (length == 0) { // common case
710 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
711 } else {
712 methodHandle h_this(THREAD, method);
713 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
714 objArrayHandle mirrors (THREAD, m_oop);
715 for (int i = 0; i < length; i++) {
716 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
717 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
718 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
719 mirrors->obj_at_put(i, k->java_mirror());
720 }
721 return mirrors;
722 }
723 };
724
725
726 int Method::line_number_from_bci(int bci) const {
727 int best_bci = 0;
728 int best_line = -1;
729 if (bci == SynchronizationEntryBCI) bci = 0;
730 if (0 <= bci && bci < code_size() && has_linenumber_table()) {
731 // The line numbers are a short array of 2-tuples [start_pc, line_number].
732 // Not necessarily sorted and not necessarily one-to-one.
733 CompressedLineNumberReadStream stream(compressed_linenumber_table());
734 while (stream.read_pair()) {
735 if (stream.bci() == bci) {
736 // perfect match
737 return stream.line();
738 } else {
739 // update best_bci/line
740 if (stream.bci() < bci && stream.bci() >= best_bci) {
741 best_bci = stream.bci();
742 best_line = stream.line();
743 }
744 }
745 }
746 }
747 return best_line;
748 }
749
750
751 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
752 if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
753 Thread *thread = Thread::current();
754 Symbol* klass_name = constants()->klass_name_at(klass_index);
755 Handle loader(thread, method_holder()->class_loader());
756 Handle prot (thread, method_holder()->protection_domain());
757 return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
758 } else {
759 return true;
760 }
761 }
762
763
764 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
765 int klass_index = constants()->klass_ref_index_at(refinfo_index);
766 if (must_be_resolved) {
767 // Make sure klass is resolved in constantpool.
768 if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
769 }
770 return is_klass_loaded_by_klass_index(klass_index);
771 }
772
773
774 void Method::set_native_function(address function, bool post_event_flag) {
775 assert(function != NULL, "use clear_native_function to unregister natives");
776 assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
777 address* native_function = native_function_addr();
778
779 // We can see racers trying to place the same native function into place. Once
780 // is plenty.
781 address current = *native_function;
782 if (current == function) return;
783 if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
784 function != NULL) {
785 // native_method_throw_unsatisfied_link_error_entry() should only
786 // be passed when post_event_flag is false.
787 assert(function !=
788 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
789 "post_event_flag mis-match");
790
791 // post the bind event, and possible change the bind function
792 JvmtiExport::post_native_method_bind(this, &function);
793 }
794 *native_function = function;
795 // This function can be called more than once. We must make sure that we always
796 // use the latest registered method -> check if a stub already has been generated.
797 // If so, we have to make it not_entrant.
798 CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
799 if (nm != NULL) {
800 nm->make_not_entrant();
801 }
802 }
803
804
805 bool Method::has_native_function() const {
806 if (is_method_handle_intrinsic())
807 return false; // special-cased in SharedRuntime::generate_native_wrapper
808 address func = native_function();
809 return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
810 }
811
812
813 void Method::clear_native_function() {
814 // Note: is_method_handle_intrinsic() is allowed here.
815 set_native_function(
816 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
817 !native_bind_event_is_interesting);
818 this->unlink_code();
819 }
820
821 address Method::critical_native_function() {
822 methodHandle mh(this);
823 return NativeLookup::lookup_critical_entry(mh);
824 }
825
826
827 void Method::set_signature_handler(address handler) {
828 address* signature_handler = signature_handler_addr();
829 *signature_handler = handler;
830 }
831
832
833 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
834 if (PrintCompilation && report) {
835 ttyLocker ttyl;
836 tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
837 if (comp_level == CompLevel_all) {
838 tty->print("all levels ");
839 } else {
840 tty->print("levels ");
841 for (int i = (int)CompLevel_none; i <= comp_level; i++) {
842 tty->print("%d ", i);
843 }
844 }
845 this->print_short_name(tty);
846 int size = this->code_size();
847 if (size > 0) {
848 tty->print(" (%d bytes)", size);
849 }
850 if (reason != NULL) {
851 tty->print(" %s", reason);
852 }
853 tty->cr();
854 }
855 if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
856 ttyLocker ttyl;
857 xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
858 os::current_thread_id(), is_osr, comp_level);
859 if (reason != NULL) {
860 xtty->print(" reason=\'%s\'", reason);
861 }
862 xtty->method(this);
863 xtty->stamp();
864 xtty->end_elem();
865 }
866 }
867
868 bool Method::is_always_compilable() const {
869 // Generated adapters must be compiled
870 if (is_method_handle_intrinsic() && is_synthetic()) {
871 assert(!is_not_c1_compilable(), "sanity check");
872 assert(!is_not_c2_compilable(), "sanity check");
873 return true;
874 }
875
876 return false;
877 }
878
879 bool Method::is_not_compilable(int comp_level) const {
880 if (number_of_breakpoints() > 0)
881 return true;
882 if (is_always_compilable())
883 return false;
884 if (comp_level == CompLevel_any)
885 return is_not_c1_compilable() || is_not_c2_compilable();
886 if (is_c1_compile(comp_level))
887 return is_not_c1_compilable();
888 if (is_c2_compile(comp_level))
889 return is_not_c2_compilable();
890 return false;
891 }
892
893 // call this when compiler finds that this method is not compilable
894 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
895 if (is_always_compilable()) {
896 // Don't mark a method which should be always compilable
897 return;
898 }
899 print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
900 if (comp_level == CompLevel_all) {
901 set_not_c1_compilable();
902 set_not_c2_compilable();
903 } else {
904 if (is_c1_compile(comp_level))
905 set_not_c1_compilable();
906 if (is_c2_compile(comp_level))
907 set_not_c2_compilable();
908 }
909 CompilationPolicy::policy()->disable_compilation(this);
910 assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
911 }
912
913 bool Method::is_not_osr_compilable(int comp_level) const {
914 if (is_not_compilable(comp_level))
915 return true;
916 if (comp_level == CompLevel_any)
917 return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
918 if (is_c1_compile(comp_level))
919 return is_not_c1_osr_compilable();
920 if (is_c2_compile(comp_level))
921 return is_not_c2_osr_compilable();
922 return false;
923 }
924
925 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
926 print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
927 if (comp_level == CompLevel_all) {
928 set_not_c1_osr_compilable();
929 set_not_c2_osr_compilable();
930 } else {
931 if (is_c1_compile(comp_level))
932 set_not_c1_osr_compilable();
933 if (is_c2_compile(comp_level))
934 set_not_c2_osr_compilable();
935 }
936 CompilationPolicy::policy()->disable_compilation(this);
937 assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
938 }
939
940 // Revert to using the interpreter and clear out the nmethod
941 void Method::clear_code() {
942 // this may be NULL if c2i adapters have not been made yet
943 // Only should happen at allocate time.
944 if (adapter() == NULL) {
945 _from_compiled_entry = NULL;
946 } else {
947 _from_compiled_entry = adapter()->get_c2i_entry();
948 }
949 OrderAccess::storestore();
950 _from_interpreted_entry = _i2i_entry;
951 OrderAccess::storestore();
952 _code = NULL;
953 }
954
955 void Method::unlink_code(CompiledMethod *compare) {
956 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
957 // We need to check if both the _code and _from_compiled_code_entry_point
958 // refer to this nmethod because there is a race in setting these two fields
959 // in Method* as seen in bugid 4947125.
960 // If the vep() points to the zombie nmethod, the memory for the nmethod
961 // could be flushed and the compiler and vtable stubs could still call
962 // through it.
963 if (code() == compare ||
964 from_compiled_entry() == compare->verified_entry_point()) {
965 clear_code();
966 }
967 }
968
969 void Method::unlink_code() {
970 MutexLocker ml(CompiledMethod_lock->owned_by_self() ? NULL : CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
971 clear_code();
972 }
973
974 #if INCLUDE_CDS
975 // Called by class data sharing to remove any entry points (which are not shared)
976 void Method::unlink_method() {
977 _code = NULL;
978
979 assert(DumpSharedSpaces, "dump time only");
980 // Set the values to what they should be at run time. Note that
981 // this Method can no longer be executed during dump time.
982 _i2i_entry = Interpreter::entry_for_cds_method(this);
983 _from_interpreted_entry = _i2i_entry;
984
985 if (is_native()) {
986 *native_function_addr() = NULL;
987 set_signature_handler(NULL);
988 }
989 NOT_PRODUCT(set_compiled_invocation_count(0);)
990
991 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
992 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
993 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
994 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
995
996 set_method_data(NULL);
997 clear_method_counters();
998 }
999 #endif
1000
1001 /****************************************************************************
1002 // The following illustrates how the entries work for CDS shared Methods:
1003 //
1004 // Our goal is to delay writing into a shared Method until it's compiled.
1005 // Hence, we want to determine the initial values for _i2i_entry,
1006 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
1007 //
1008 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
1009 // They also have similar signatures so that they will share the same
1010 // AdapterHandlerEntry.
1011 //
1012 // _adapter_trampoline points to a fixed location in the RW section of
1013 // the CDS archive. This location initially contains a NULL pointer. When the
1014 // first of method A or B is linked, an AdapterHandlerEntry is allocated
1015 // dynamically, and its c2i/i2c entries are generated.
1016 //
1017 // _i2i_entry and _from_interpreted_entry initially points to the same
1018 // (fixed) location in the CODE section of the CDS archive. This contains
1019 // an unconditional branch to the actual entry for "zero_locals", which is
1020 // generated at run time and may be on an arbitrary address. Thus, the
1021 // unconditional branch is also generated at run time to jump to the correct
1022 // address.
1023 //
1024 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1025 // section. This address has enough space for an unconditional branch
1026 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1027 // initialized, and the address for the actual c2i_entry is known, we emit a
1028 // branch instruction here to branch to the actual c2i_entry.
1029 //
1030 // The effect of the extra branch on the i2i and c2i entries is negligible.
1031 //
1032 // The reason for putting _adapter_trampoline in RO is many shared Methods
1033 // share the same AdapterHandlerEntry, so we can save space in the RW section
1034 // by having the extra indirection.
1035
1036
1037 [Method A: RW]
1038 _constMethod ----> [ConstMethod: RO]
1039 _adapter_trampoline -----------+
1040 |
1041 _i2i_entry (same value as method B) |
1042 _from_interpreted_entry (same value as method B) |
1043 _from_compiled_entry (same value as method B) |
1044 |
1045 |
1046 [Method B: RW] +--------+
1047 _constMethod ----> [ConstMethod: RO] |
1048 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1049 |
1050 +-------------------------------+
1051 |
1052 +----> [AdapterHandlerEntry] (allocated at run time)
1053 _fingerprint
1054 _c2i_entry ---------------------------------+->[c2i entry..]
1055 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1056 _from_interpreted_entry | _c2i_unverified_entry | |
1057 | | | |
1058 | | (_cds_entry_table: CODE) | |
1059 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1060 | | (allocated at run time) | |
1061 | | ... [asm code ...] | |
1062 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1063 | | |
1064 | | |
1065 +-[compiled]-------------------------------------------------------------------+ |
1066 |
1067 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1068 [jmp c2i_entry] ------------------------------------------------------+
1069
1070 ***/
1071
1072 // Called when the method_holder is getting linked. Setup entrypoints so the method
1073 // is ready to be called from interpreter, compiler, and vtables.
1074 void Method::link_method(const methodHandle& h_method, TRAPS) {
1075 // If the code cache is full, we may reenter this function for the
1076 // leftover methods that weren't linked.
1077 if (is_shared()) {
1078 address entry = Interpreter::entry_for_cds_method(h_method);
1079 assert(entry != NULL && entry == _i2i_entry,
1080 "should be correctly set during dump time");
1081 if (adapter() != NULL) {
1082 return;
1083 }
1084 assert(entry == _from_interpreted_entry,
1085 "should be correctly set during dump time");
1086 } else if (_i2i_entry != NULL) {
1087 return;
1088 }
1089 assert( _code == NULL, "nothing compiled yet" );
1090
1091 // Setup interpreter entrypoint
1092 assert(this == h_method(), "wrong h_method()" );
1093
1094 if (!is_shared()) {
1095 assert(adapter() == NULL, "init'd to NULL");
1096 address entry = Interpreter::entry_for_method(h_method);
1097 assert(entry != NULL, "interpreter entry must be non-null");
1098 // Sets both _i2i_entry and _from_interpreted_entry
1099 set_interpreter_entry(entry);
1100 }
1101
1102 // Don't overwrite already registered native entries.
1103 if (is_native() && !has_native_function()) {
1104 set_native_function(
1105 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1106 !native_bind_event_is_interesting);
1107 }
1108
1109 // Setup compiler entrypoint. This is made eagerly, so we do not need
1110 // special handling of vtables. An alternative is to make adapters more
1111 // lazily by calling make_adapter() from from_compiled_entry() for the
1112 // normal calls. For vtable calls life gets more complicated. When a
1113 // call-site goes mega-morphic we need adapters in all methods which can be
1114 // called from the vtable. We need adapters on such methods that get loaded
1115 // later. Ditto for mega-morphic itable calls. If this proves to be a
1116 // problem we'll make these lazily later.
1117 (void) make_adapters(h_method, CHECK);
1118
1119 // ONLY USE the h_method now as make_adapter may have blocked
1120
1121 }
1122
1123 address Method::make_adapters(const methodHandle& mh, TRAPS) {
1124 // Adapters for compiled code are made eagerly here. They are fairly
1125 // small (generally < 100 bytes) and quick to make (and cached and shared)
1126 // so making them eagerly shouldn't be too expensive.
1127 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1128 if (adapter == NULL ) {
1129 if (!is_init_completed()) {
1130 // Don't throw exceptions during VM initialization because java.lang.* classes
1131 // might not have been initialized, causing problems when constructing the
1132 // Java exception object.
1133 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1134 } else {
1135 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1136 }
1137 }
1138
1139 if (mh->is_shared()) {
1140 assert(mh->adapter() == adapter, "must be");
1141 assert(mh->_from_compiled_entry != NULL, "must be");
1142 } else {
1143 mh->set_adapter_entry(adapter);
1144 mh->_from_compiled_entry = adapter->get_c2i_entry();
1145 }
1146 return adapter->get_c2i_entry();
1147 }
1148
1149 void Method::restore_unshareable_info(TRAPS) {
1150 assert(is_method() && is_valid_method(this), "ensure C++ vtable is restored");
1151
1152 // Since restore_unshareable_info can be called more than once for a method, don't
1153 // redo any work.
1154 if (adapter() == NULL) {
1155 methodHandle mh(THREAD, this);
1156 link_method(mh, CHECK);
1157 }
1158 }
1159
1160 address Method::from_compiled_entry_no_trampoline() const {
1161 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1162 if (code) {
1163 return code->verified_entry_point();
1164 } else {
1165 return adapter()->get_c2i_entry();
1166 }
1167 }
1168
1169 // The verified_code_entry() must be called when a invoke is resolved
1170 // on this method.
1171
1172 // It returns the compiled code entry point, after asserting not null.
1173 // This function is called after potential safepoints so that nmethod
1174 // or adapter that it points to is still live and valid.
1175 // This function must not hit a safepoint!
1176 address Method::verified_code_entry() {
1177 debug_only(NoSafepointVerifier nsv;)
1178 assert(_from_compiled_entry != NULL, "must be set");
1179 return _from_compiled_entry;
1180 }
1181
1182 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1183 // (could be racing a deopt).
1184 // Not inline to avoid circular ref.
1185 bool Method::check_code() const {
1186 // cached in a register or local. There's a race on the value of the field.
1187 CompiledMethod *code = OrderAccess::load_acquire(&_code);
1188 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1189 }
1190
1191 // Install compiled code. Instantly it can execute.
1192 void Method::set_code(const methodHandle& mh, CompiledMethod *code) {
1193 MutexLocker pl(CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
1194 assert( code, "use clear_code to remove code" );
1195 assert( mh->check_code(), "" );
1196
1197 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1198
1199 // These writes must happen in this order, because the interpreter will
1200 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1201 // which jumps to _from_compiled_entry.
1202 mh->_code = code; // Assign before allowing compiled code to exec
1203
1204 int comp_level = code->comp_level();
1205 // In theory there could be a race here. In practice it is unlikely
1206 // and not worth worrying about.
1207 if (comp_level > mh->highest_comp_level()) {
1208 mh->set_highest_comp_level(comp_level);
1209 }
1210
1211 OrderAccess::storestore();
1212 mh->_from_compiled_entry = code->verified_entry_point();
1213 OrderAccess::storestore();
1214 // Instantly compiled code can execute.
1215 if (!mh->is_method_handle_intrinsic())
1216 mh->_from_interpreted_entry = mh->get_i2c_entry();
1217 }
1218
1219
1220 bool Method::is_overridden_in(Klass* k) const {
1221 InstanceKlass* ik = InstanceKlass::cast(k);
1222
1223 if (ik->is_interface()) return false;
1224
1225 // If method is an interface, we skip it - except if it
1226 // is a miranda method
1227 if (method_holder()->is_interface()) {
1228 // Check that method is not a miranda method
1229 if (ik->lookup_method(name(), signature()) == NULL) {
1230 // No implementation exist - so miranda method
1231 return false;
1232 }
1233 return true;
1234 }
1235
1236 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1237 if (!has_vtable_index()) {
1238 return false;
1239 } else {
1240 Method* vt_m = ik->method_at_vtable(vtable_index());
1241 return vt_m != this;
1242 }
1243 }
1244
1245
1246 // give advice about whether this Method* should be cached or not
1247 bool Method::should_not_be_cached() const {
1248 if (is_old()) {
1249 // This method has been redefined. It is either EMCP or obsolete
1250 // and we don't want to cache it because that would pin the method
1251 // down and prevent it from being collectible if and when it
1252 // finishes executing.
1253 return true;
1254 }
1255
1256 // caching this method should be just fine
1257 return false;
1258 }
1259
1260
1261 /**
1262 * Returns true if this is one of the specially treated methods for
1263 * security related stack walks (like Reflection.getCallerClass).
1264 */
1265 bool Method::is_ignored_by_security_stack_walk() const {
1266 if (intrinsic_id() == vmIntrinsics::_invoke) {
1267 // This is Method.invoke() -- ignore it
1268 return true;
1269 }
1270 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1271 // This is an auxilary frame -- ignore it
1272 return true;
1273 }
1274 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1275 // This is an internal adapter frame for method handles -- ignore it
1276 return true;
1277 }
1278 return false;
1279 }
1280
1281
1282 // Constant pool structure for invoke methods:
1283 enum {
1284 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1285 _imcp_invoke_signature, // utf8: (variable Symbol*)
1286 _imcp_limit
1287 };
1288
1289 // Test if this method is an MH adapter frame generated by Java code.
1290 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1291 bool Method::is_compiled_lambda_form() const {
1292 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1293 }
1294
1295 // Test if this method is an internal MH primitive method.
1296 bool Method::is_method_handle_intrinsic() const {
1297 vmIntrinsics::ID iid = intrinsic_id();
1298 return (MethodHandles::is_signature_polymorphic(iid) &&
1299 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1300 }
1301
1302 bool Method::has_member_arg() const {
1303 vmIntrinsics::ID iid = intrinsic_id();
1304 return (MethodHandles::is_signature_polymorphic(iid) &&
1305 MethodHandles::has_member_arg(iid));
1306 }
1307
1308 // Make an instance of a signature-polymorphic internal MH primitive.
1309 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1310 Symbol* signature,
1311 TRAPS) {
1312 ResourceMark rm;
1313 methodHandle empty;
1314
1315 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1316 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1317 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1318 if (TraceMethodHandles) {
1319 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1320 }
1321
1322 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1323 name->increment_refcount();
1324 signature->increment_refcount();
1325
1326 int cp_length = _imcp_limit;
1327 ClassLoaderData* loader_data = holder->class_loader_data();
1328 constantPoolHandle cp;
1329 {
1330 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1331 cp = constantPoolHandle(THREAD, cp_oop);
1332 }
1333 cp->set_pool_holder(holder);
1334 cp->symbol_at_put(_imcp_invoke_name, name);
1335 cp->symbol_at_put(_imcp_invoke_signature, signature);
1336 cp->set_has_preresolution();
1337
1338 // decide on access bits: public or not?
1339 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1340 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1341 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1342 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1343
1344 methodHandle m;
1345 {
1346 InlineTableSizes sizes;
1347 Method* m_oop = Method::allocate(loader_data, 0,
1348 accessFlags_from(flags_bits), &sizes,
1349 ConstMethod::NORMAL, CHECK_(empty));
1350 m = methodHandle(THREAD, m_oop);
1351 }
1352 m->set_constants(cp());
1353 m->set_name_index(_imcp_invoke_name);
1354 m->set_signature_index(_imcp_invoke_signature);
1355 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1356 assert(m->signature() == signature, "");
1357 ResultTypeFinder rtf(signature);
1358 m->constMethod()->set_result_type(rtf.type());
1359 m->compute_size_of_parameters(THREAD);
1360 m->init_intrinsic_id();
1361 assert(m->is_method_handle_intrinsic(), "");
1362 #ifdef ASSERT
1363 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1364 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1365 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1366 #endif //ASSERT
1367
1368 // Finally, set up its entry points.
1369 assert(m->can_be_statically_bound(), "");
1370 m->set_vtable_index(Method::nonvirtual_vtable_index);
1371 m->link_method(m, CHECK_(empty));
1372
1373 if (TraceMethodHandles && (Verbose || WizardMode)) {
1374 ttyLocker ttyl;
1375 m->print_on(tty);
1376 }
1377
1378 return m;
1379 }
1380
1381 Klass* Method::check_non_bcp_klass(Klass* klass) {
1382 if (klass != NULL && klass->class_loader() != NULL) {
1383 if (klass->is_objArray_klass())
1384 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1385 return klass;
1386 }
1387 return NULL;
1388 }
1389
1390
1391 methodHandle Method::clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
1392 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1393 // Code below does not work for native methods - they should never get rewritten anyway
1394 assert(!m->is_native(), "cannot rewrite native methods");
1395 // Allocate new Method*
1396 AccessFlags flags = m->access_flags();
1397
1398 ConstMethod* cm = m->constMethod();
1399 int checked_exceptions_len = cm->checked_exceptions_length();
1400 int localvariable_len = cm->localvariable_table_length();
1401 int exception_table_len = cm->exception_table_length();
1402 int method_parameters_len = cm->method_parameters_length();
1403 int method_annotations_len = cm->method_annotations_length();
1404 int parameter_annotations_len = cm->parameter_annotations_length();
1405 int type_annotations_len = cm->type_annotations_length();
1406 int default_annotations_len = cm->default_annotations_length();
1407
1408 InlineTableSizes sizes(
1409 localvariable_len,
1410 new_compressed_linenumber_size,
1411 exception_table_len,
1412 checked_exceptions_len,
1413 method_parameters_len,
1414 cm->generic_signature_index(),
1415 method_annotations_len,
1416 parameter_annotations_len,
1417 type_annotations_len,
1418 default_annotations_len,
1419 0);
1420
1421 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1422 Method* newm_oop = Method::allocate(loader_data,
1423 new_code_length,
1424 flags,
1425 &sizes,
1426 m->method_type(),
1427 CHECK_(methodHandle()));
1428 methodHandle newm (THREAD, newm_oop);
1429
1430 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1431 ConstMethod* newcm = newm->constMethod();
1432 int new_const_method_size = newm->constMethod()->size();
1433
1434 // This works because the source and target are both Methods. Some compilers
1435 // (e.g., clang) complain that the target vtable pointer will be stomped,
1436 // so cast away newm()'s and m()'s Methodness.
1437 memcpy((void*)newm(), (void*)m(), sizeof(Method));
1438
1439 // Create shallow copy of ConstMethod.
1440 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1441
1442 // Reset correct method/const method, method size, and parameter info
1443 newm->set_constMethod(newcm);
1444 newm->constMethod()->set_code_size(new_code_length);
1445 newm->constMethod()->set_constMethod_size(new_const_method_size);
1446 assert(newm->code_size() == new_code_length, "check");
1447 assert(newm->method_parameters_length() == method_parameters_len, "check");
1448 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1449 assert(newm->exception_table_length() == exception_table_len, "check");
1450 assert(newm->localvariable_table_length() == localvariable_len, "check");
1451 // Copy new byte codes
1452 memcpy(newm->code_base(), new_code, new_code_length);
1453 // Copy line number table
1454 if (new_compressed_linenumber_size > 0) {
1455 memcpy(newm->compressed_linenumber_table(),
1456 new_compressed_linenumber_table,
1457 new_compressed_linenumber_size);
1458 }
1459 // Copy method_parameters
1460 if (method_parameters_len > 0) {
1461 memcpy(newm->method_parameters_start(),
1462 m->method_parameters_start(),
1463 method_parameters_len * sizeof(MethodParametersElement));
1464 }
1465 // Copy checked_exceptions
1466 if (checked_exceptions_len > 0) {
1467 memcpy(newm->checked_exceptions_start(),
1468 m->checked_exceptions_start(),
1469 checked_exceptions_len * sizeof(CheckedExceptionElement));
1470 }
1471 // Copy exception table
1472 if (exception_table_len > 0) {
1473 memcpy(newm->exception_table_start(),
1474 m->exception_table_start(),
1475 exception_table_len * sizeof(ExceptionTableElement));
1476 }
1477 // Copy local variable number table
1478 if (localvariable_len > 0) {
1479 memcpy(newm->localvariable_table_start(),
1480 m->localvariable_table_start(),
1481 localvariable_len * sizeof(LocalVariableTableElement));
1482 }
1483 // Copy stackmap table
1484 if (m->has_stackmap_table()) {
1485 int code_attribute_length = m->stackmap_data()->length();
1486 Array<u1>* stackmap_data =
1487 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1488 memcpy((void*)stackmap_data->adr_at(0),
1489 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1490 newm->set_stackmap_data(stackmap_data);
1491 }
1492
1493 // copy annotations over to new method
1494 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1495 return newm;
1496 }
1497
1498 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1499 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1500 // because we are not loading from core libraries
1501 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1502 // which does not use the class default class loader so we check for its loader here
1503 const InstanceKlass* ik = InstanceKlass::cast(holder);
1504 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1505 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1506 }
1507
1508 // see if the klass name is well-known:
1509 Symbol* klass_name = ik->name();
1510 return vmSymbols::find_sid(klass_name);
1511 }
1512
1513 void Method::init_intrinsic_id() {
1514 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1515 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1516 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1517 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1518
1519 // the klass name is well-known:
1520 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1521 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1522
1523 // ditto for method and signature:
1524 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1525 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1526 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1527 && name_id == vmSymbols::NO_SID) {
1528 return;
1529 }
1530 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1531 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1532 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1533 && sig_id == vmSymbols::NO_SID) {
1534 return;
1535 }
1536 jshort flags = access_flags().as_short();
1537
1538 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1539 if (id != vmIntrinsics::_none) {
1540 set_intrinsic_id(id);
1541 if (id == vmIntrinsics::_Class_cast) {
1542 // Even if the intrinsic is rejected, we want to inline this simple method.
1543 set_force_inline(true);
1544 }
1545 return;
1546 }
1547
1548 // A few slightly irregular cases:
1549 switch (klass_id) {
1550 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1551 // Second chance: check in regular Math.
1552 switch (name_id) {
1553 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1554 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1555 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1556 // pretend it is the corresponding method in the non-strict class:
1557 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1558 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1559 break;
1560 default:
1561 break;
1562 }
1563 break;
1564
1565 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1566 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1567 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1568 if (!is_native()) break;
1569 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1570 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1571 id = vmIntrinsics::_none;
1572 break;
1573
1574 default:
1575 break;
1576 }
1577
1578 if (id != vmIntrinsics::_none) {
1579 // Set up its iid. It is an alias method.
1580 set_intrinsic_id(id);
1581 return;
1582 }
1583 }
1584
1585 // These two methods are static since a GC may move the Method
1586 bool Method::load_signature_classes(const methodHandle& m, TRAPS) {
1587 if (!THREAD->can_call_java()) {
1588 // There is nothing useful this routine can do from within the Compile thread.
1589 // Hopefully, the signature contains only well-known classes.
1590 // We could scan for this and return true/false, but the caller won't care.
1591 return false;
1592 }
1593 bool sig_is_loaded = true;
1594 Handle class_loader(THREAD, m->method_holder()->class_loader());
1595 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1596 ResourceMark rm(THREAD);
1597 Symbol* signature = m->signature();
1598 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1599 if (ss.is_object()) {
1600 Symbol* sym = ss.as_symbol(CHECK_(false));
1601 Symbol* name = sym;
1602 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1603 protection_domain, THREAD);
1604 // We are loading classes eagerly. If a ClassNotFoundException or
1605 // a LinkageError was generated, be sure to ignore it.
1606 if (HAS_PENDING_EXCEPTION) {
1607 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1608 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1609 CLEAR_PENDING_EXCEPTION;
1610 } else {
1611 return false;
1612 }
1613 }
1614 if( klass == NULL) { sig_is_loaded = false; }
1615 }
1616 }
1617 return sig_is_loaded;
1618 }
1619
1620 bool Method::has_unloaded_classes_in_signature(const methodHandle& m, TRAPS) {
1621 Handle class_loader(THREAD, m->method_holder()->class_loader());
1622 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1623 ResourceMark rm(THREAD);
1624 Symbol* signature = m->signature();
1625 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1626 if (ss.type() == T_OBJECT) {
1627 Symbol* name = ss.as_symbol_or_null();
1628 if (name == NULL) return true;
1629 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1630 if (klass == NULL) return true;
1631 }
1632 }
1633 return false;
1634 }
1635
1636 // Exposed so field engineers can debug VM
1637 void Method::print_short_name(outputStream* st) {
1638 ResourceMark rm;
1639 #ifdef PRODUCT
1640 st->print(" %s::", method_holder()->external_name());
1641 #else
1642 st->print(" %s::", method_holder()->internal_name());
1643 #endif
1644 name()->print_symbol_on(st);
1645 if (WizardMode) signature()->print_symbol_on(st);
1646 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1647 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1648 }
1649
1650 // Comparer for sorting an object array containing
1651 // Method*s.
1652 static int method_comparator(Method* a, Method* b) {
1653 return a->name()->fast_compare(b->name());
1654 }
1655
1656 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1657 // default_methods also uses this without the ordering for fast find_method
1658 void Method::sort_methods(Array<Method*>* methods, bool set_idnums) {
1659 int length = methods->length();
1660 if (length > 1) {
1661 {
1662 NoSafepointVerifier nsv;
1663 QuickSort::sort(methods->data(), length, method_comparator, /*idempotent=*/false);
1664 }
1665 // Reset method ordering
1666 if (set_idnums) {
1667 for (int i = 0; i < length; i++) {
1668 Method* m = methods->at(i);
1669 m->set_method_idnum(i);
1670 m->set_orig_method_idnum(i);
1671 }
1672 }
1673 }
1674 }
1675
1676 //-----------------------------------------------------------------------------------
1677 // Non-product code unless JVM/TI needs it
1678
1679 #if !defined(PRODUCT) || INCLUDE_JVMTI
1680 class SignatureTypePrinter : public SignatureTypeNames {
1681 private:
1682 outputStream* _st;
1683 bool _use_separator;
1684
1685 void type_name(const char* name) {
1686 if (_use_separator) _st->print(", ");
1687 _st->print("%s", name);
1688 _use_separator = true;
1689 }
1690
1691 public:
1692 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1693 _st = st;
1694 _use_separator = false;
1695 }
1696
1697 void print_parameters() { _use_separator = false; iterate_parameters(); }
1698 void print_returntype() { _use_separator = false; iterate_returntype(); }
1699 };
1700
1701
1702 void Method::print_name(outputStream* st) {
1703 Thread *thread = Thread::current();
1704 ResourceMark rm(thread);
1705 st->print("%s ", is_static() ? "static" : "virtual");
1706 if (WizardMode) {
1707 st->print("%s.", method_holder()->internal_name());
1708 name()->print_symbol_on(st);
1709 signature()->print_symbol_on(st);
1710 } else {
1711 SignatureTypePrinter sig(signature(), st);
1712 sig.print_returntype();
1713 st->print(" %s.", method_holder()->internal_name());
1714 name()->print_symbol_on(st);
1715 st->print("(");
1716 sig.print_parameters();
1717 st->print(")");
1718 }
1719 }
1720 #endif // !PRODUCT || INCLUDE_JVMTI
1721
1722
1723 void Method::print_codes_on(outputStream* st) const {
1724 print_codes_on(0, code_size(), st);
1725 }
1726
1727 void Method::print_codes_on(int from, int to, outputStream* st) const {
1728 Thread *thread = Thread::current();
1729 ResourceMark rm(thread);
1730 methodHandle mh (thread, (Method*)this);
1731 BytecodeStream s(mh);
1732 s.set_interval(from, to);
1733 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1734 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1735 }
1736
1737 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1738 _bci = 0;
1739 _line = 0;
1740 };
1741
1742 bool CompressedLineNumberReadStream::read_pair() {
1743 jubyte next = read_byte();
1744 // Check for terminator
1745 if (next == 0) return false;
1746 if (next == 0xFF) {
1747 // Escape character, regular compression used
1748 _bci += read_signed_int();
1749 _line += read_signed_int();
1750 } else {
1751 // Single byte compression used
1752 _bci += next >> 3;
1753 _line += next & 0x7;
1754 }
1755 return true;
1756 }
1757
1758 #if INCLUDE_JVMTI
1759
1760 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1761 BreakpointInfo* bp = method_holder()->breakpoints();
1762 for (; bp != NULL; bp = bp->next()) {
1763 if (bp->match(this, bci)) {
1764 return bp->orig_bytecode();
1765 }
1766 }
1767 {
1768 ResourceMark rm;
1769 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1770 }
1771 return Bytecodes::_shouldnotreachhere;
1772 }
1773
1774 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1775 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1776 BreakpointInfo* bp = method_holder()->breakpoints();
1777 for (; bp != NULL; bp = bp->next()) {
1778 if (bp->match(this, bci)) {
1779 bp->set_orig_bytecode(code);
1780 // and continue, in case there is more than one
1781 }
1782 }
1783 }
1784
1785 void Method::set_breakpoint(int bci) {
1786 InstanceKlass* ik = method_holder();
1787 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1788 bp->set_next(ik->breakpoints());
1789 ik->set_breakpoints(bp);
1790 // do this last:
1791 bp->set(this);
1792 }
1793
1794 static void clear_matches(Method* m, int bci) {
1795 InstanceKlass* ik = m->method_holder();
1796 BreakpointInfo* prev_bp = NULL;
1797 BreakpointInfo* next_bp;
1798 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1799 next_bp = bp->next();
1800 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1801 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1802 // do this first:
1803 bp->clear(m);
1804 // unhook it
1805 if (prev_bp != NULL)
1806 prev_bp->set_next(next_bp);
1807 else
1808 ik->set_breakpoints(next_bp);
1809 delete bp;
1810 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1811 // at same location. So we have multiple matching (method_index and bci)
1812 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1813 // breakpoint for clear_breakpoint request and keep all other method versions
1814 // BreakpointInfo for future clear_breakpoint request.
1815 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1816 // which is being called when class is unloaded. We delete all the Breakpoint
1817 // information for all versions of method. We may not correctly restore the original
1818 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1819 // so these methods won't be used anymore.
1820 if (bci >= 0) {
1821 break;
1822 }
1823 } else {
1824 // This one is a keeper.
1825 prev_bp = bp;
1826 }
1827 }
1828 }
1829
1830 void Method::clear_breakpoint(int bci) {
1831 assert(bci >= 0, "");
1832 clear_matches(this, bci);
1833 }
1834
1835 void Method::clear_all_breakpoints() {
1836 clear_matches(this, -1);
1837 }
1838
1839 #endif // INCLUDE_JVMTI
1840
1841 int Method::invocation_count() {
1842 MethodCounters *mcs = method_counters();
1843 if (TieredCompilation) {
1844 MethodData* const mdo = method_data();
1845 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1846 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1847 return InvocationCounter::count_limit;
1848 } else {
1849 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1850 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1851 }
1852 } else {
1853 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1854 }
1855 }
1856
1857 int Method::backedge_count() {
1858 MethodCounters *mcs = method_counters();
1859 if (TieredCompilation) {
1860 MethodData* const mdo = method_data();
1861 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1862 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1863 return InvocationCounter::count_limit;
1864 } else {
1865 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1866 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1867 }
1868 } else {
1869 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1870 }
1871 }
1872
1873 int Method::highest_comp_level() const {
1874 const MethodCounters* mcs = method_counters();
1875 if (mcs != NULL) {
1876 return mcs->highest_comp_level();
1877 } else {
1878 return CompLevel_none;
1879 }
1880 }
1881
1882 int Method::highest_osr_comp_level() const {
1883 const MethodCounters* mcs = method_counters();
1884 if (mcs != NULL) {
1885 return mcs->highest_osr_comp_level();
1886 } else {
1887 return CompLevel_none;
1888 }
1889 }
1890
1891 void Method::set_highest_comp_level(int level) {
1892 MethodCounters* mcs = method_counters();
1893 if (mcs != NULL) {
1894 mcs->set_highest_comp_level(level);
1895 }
1896 }
1897
1898 void Method::set_highest_osr_comp_level(int level) {
1899 MethodCounters* mcs = method_counters();
1900 if (mcs != NULL) {
1901 mcs->set_highest_osr_comp_level(level);
1902 }
1903 }
1904
1905 #if INCLUDE_JVMTI
1906
1907 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1908 _bci = bci;
1909 _name_index = m->name_index();
1910 _signature_index = m->signature_index();
1911 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1912 if (_orig_bytecode == Bytecodes::_breakpoint)
1913 _orig_bytecode = m->orig_bytecode_at(_bci);
1914 _next = NULL;
1915 }
1916
1917 void BreakpointInfo::set(Method* method) {
1918 #ifdef ASSERT
1919 {
1920 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1921 if (code == Bytecodes::_breakpoint)
1922 code = method->orig_bytecode_at(_bci);
1923 assert(orig_bytecode() == code, "original bytecode must be the same");
1924 }
1925 #endif
1926 Thread *thread = Thread::current();
1927 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1928 method->incr_number_of_breakpoints(thread);
1929 SystemDictionary::notice_modification();
1930 {
1931 // Deoptimize all dependents on this method
1932 HandleMark hm(thread);
1933 methodHandle mh(thread, method);
1934 CodeCache::flush_dependents_on_method(mh);
1935 }
1936 }
1937
1938 void BreakpointInfo::clear(Method* method) {
1939 *method->bcp_from(_bci) = orig_bytecode();
1940 assert(method->number_of_breakpoints() > 0, "must not go negative");
1941 method->decr_number_of_breakpoints(Thread::current());
1942 }
1943
1944 #endif // INCLUDE_JVMTI
1945
1946 // jmethodID handling
1947
1948 // This is a block allocating object, sort of like JNIHandleBlock, only a
1949 // lot simpler.
1950 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1951 // never get rid of it.
1952
1953 static const int min_block_size = 8;
1954
1955 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1956 friend class JNIMethodBlock;
1957 Method** _methods;
1958 int _number_of_methods;
1959 int _top;
1960 JNIMethodBlockNode* _next;
1961
1962 public:
1963
1964 JNIMethodBlockNode(int num_methods = min_block_size);
1965
1966 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1967
1968 void ensure_methods(int num_addl_methods) {
1969 if (_top < _number_of_methods) {
1970 num_addl_methods -= _number_of_methods - _top;
1971 if (num_addl_methods <= 0) {
1972 return;
1973 }
1974 }
1975 if (_next == NULL) {
1976 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1977 } else {
1978 _next->ensure_methods(num_addl_methods);
1979 }
1980 }
1981 };
1982
1983 class JNIMethodBlock : public CHeapObj<mtClass> {
1984 JNIMethodBlockNode _head;
1985 JNIMethodBlockNode *_last_free;
1986 public:
1987 static Method* const _free_method;
1988
1989 JNIMethodBlock(int initial_capacity = min_block_size)
1990 : _head(initial_capacity), _last_free(&_head) {}
1991
1992 void ensure_methods(int num_addl_methods) {
1993 _last_free->ensure_methods(num_addl_methods);
1994 }
1995
1996 Method** add_method(Method* m) {
1997 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1998 if (b->_top < b->_number_of_methods) {
1999 // top points to the next free entry.
2000 int i = b->_top;
2001 b->_methods[i] = m;
2002 b->_top++;
2003 _last_free = b;
2004 return &(b->_methods[i]);
2005 } else if (b->_top == b->_number_of_methods) {
2006 // if the next free entry ran off the block see if there's a free entry
2007 for (int i = 0; i < b->_number_of_methods; i++) {
2008 if (b->_methods[i] == _free_method) {
2009 b->_methods[i] = m;
2010 _last_free = b;
2011 return &(b->_methods[i]);
2012 }
2013 }
2014 // Only check each block once for frees. They're very unlikely.
2015 // Increment top past the end of the block.
2016 b->_top++;
2017 }
2018 // need to allocate a next block.
2019 if (b->_next == NULL) {
2020 b->_next = _last_free = new JNIMethodBlockNode();
2021 }
2022 }
2023 guarantee(false, "Should always allocate a free block");
2024 return NULL;
2025 }
2026
2027 bool contains(Method** m) {
2028 if (m == NULL) return false;
2029 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2030 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2031 // This is a bit of extra checking, for two reasons. One is
2032 // that contains() deals with pointers that are passed in by
2033 // JNI code, so making sure that the pointer is aligned
2034 // correctly is valuable. The other is that <= and > are
2035 // technically not defined on pointers, so the if guard can
2036 // pass spuriously; no modern compiler is likely to make that
2037 // a problem, though (and if one did, the guard could also
2038 // fail spuriously, which would be bad).
2039 ptrdiff_t idx = m - b->_methods;
2040 if (b->_methods + idx == m) {
2041 return true;
2042 }
2043 }
2044 }
2045 return false; // not found
2046 }
2047
2048 // Doesn't really destroy it, just marks it as free so it can be reused.
2049 void destroy_method(Method** m) {
2050 #ifdef ASSERT
2051 assert(contains(m), "should be a methodID");
2052 #endif // ASSERT
2053 *m = _free_method;
2054 }
2055
2056 // During class unloading the methods are cleared, which is different
2057 // than freed.
2058 void clear_all_methods() {
2059 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2060 for (int i = 0; i< b->_number_of_methods; i++) {
2061 b->_methods[i] = NULL;
2062 }
2063 }
2064 }
2065 #ifndef PRODUCT
2066 int count_methods() {
2067 // count all allocated methods
2068 int count = 0;
2069 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2070 for (int i = 0; i< b->_number_of_methods; i++) {
2071 if (b->_methods[i] != _free_method) count++;
2072 }
2073 }
2074 return count;
2075 }
2076 #endif // PRODUCT
2077 };
2078
2079 // Something that can't be mistaken for an address or a markOop
2080 Method* const JNIMethodBlock::_free_method = (Method*)55;
2081
2082 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _top(0), _next(NULL) {
2083 _number_of_methods = MAX2(num_methods, min_block_size);
2084 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2085 for (int i = 0; i < _number_of_methods; i++) {
2086 _methods[i] = JNIMethodBlock::_free_method;
2087 }
2088 }
2089
2090 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2091 ClassLoaderData* cld = loader_data;
2092 if (!SafepointSynchronize::is_at_safepoint()) {
2093 // Have to add jmethod_ids() to class loader data thread-safely.
2094 // Also have to add the method to the list safely, which the cld lock
2095 // protects as well.
2096 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2097 if (cld->jmethod_ids() == NULL) {
2098 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2099 } else {
2100 cld->jmethod_ids()->ensure_methods(capacity);
2101 }
2102 } else {
2103 // At safepoint, we are single threaded and can set this.
2104 if (cld->jmethod_ids() == NULL) {
2105 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2106 } else {
2107 cld->jmethod_ids()->ensure_methods(capacity);
2108 }
2109 }
2110 }
2111
2112 // Add a method id to the jmethod_ids
2113 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2114 ClassLoaderData* cld = loader_data;
2115
2116 if (!SafepointSynchronize::is_at_safepoint()) {
2117 // Have to add jmethod_ids() to class loader data thread-safely.
2118 // Also have to add the method to the list safely, which the cld lock
2119 // protects as well.
2120 MutexLocker ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2121 if (cld->jmethod_ids() == NULL) {
2122 cld->set_jmethod_ids(new JNIMethodBlock());
2123 }
2124 // jmethodID is a pointer to Method*
2125 return (jmethodID)cld->jmethod_ids()->add_method(m);
2126 } else {
2127 // At safepoint, we are single threaded and can set this.
2128 if (cld->jmethod_ids() == NULL) {
2129 cld->set_jmethod_ids(new JNIMethodBlock());
2130 }
2131 // jmethodID is a pointer to Method*
2132 return (jmethodID)cld->jmethod_ids()->add_method(m);
2133 }
2134 }
2135
2136 // Mark a jmethodID as free. This is called when there is a data race in
2137 // InstanceKlass while creating the jmethodID cache.
2138 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2139 ClassLoaderData* cld = loader_data;
2140 Method** ptr = (Method**)m;
2141 assert(cld->jmethod_ids() != NULL, "should have method handles");
2142 cld->jmethod_ids()->destroy_method(ptr);
2143 }
2144
2145 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2146 // Can't assert the method_holder is the same because the new method has the
2147 // scratch method holder.
2148 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2149 == new_method->method_holder()->class_loader() ||
2150 new_method->method_holder()->class_loader() == NULL, // allow Unsafe substitution
2151 "changing to a different class loader");
2152 // Just change the method in place, jmethodID pointer doesn't change.
2153 *((Method**)jmid) = new_method;
2154 }
2155
2156 bool Method::is_method_id(jmethodID mid) {
2157 Method* m = resolve_jmethod_id(mid);
2158 assert(m != NULL, "should be called with non-null method");
2159 InstanceKlass* ik = m->method_holder();
2160 ClassLoaderData* cld = ik->class_loader_data();
2161 if (cld->jmethod_ids() == NULL) return false;
2162 return (cld->jmethod_ids()->contains((Method**)mid));
2163 }
2164
2165 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2166 if (mid == NULL) return NULL;
2167 Method* o = resolve_jmethod_id(mid);
2168 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2169 return NULL;
2170 }
2171 return o;
2172 };
2173
2174 void Method::set_on_stack(const bool value) {
2175 // Set both the method itself and its constant pool. The constant pool
2176 // on stack means some method referring to it is also on the stack.
2177 constants()->set_on_stack(value);
2178
2179 bool already_set = on_stack();
2180 _access_flags.set_on_stack(value);
2181 if (value && !already_set) {
2182 MetadataOnStackMark::record(this);
2183 }
2184 assert(!value || !is_old() || is_obsolete() || is_running_emcp(),
2185 "emcp methods cannot run after emcp bit is cleared");
2186 }
2187
2188 // Called when the class loader is unloaded to make all methods weak.
2189 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2190 loader_data->jmethod_ids()->clear_all_methods();
2191 }
2192
2193 bool Method::has_method_vptr(const void* ptr) {
2194 Method m;
2195 // This assumes that the vtbl pointer is the first word of a C++ object.
2196 return dereference_vptr(&m) == dereference_vptr(ptr);
2197 }
2198
2199 // Check that this pointer is valid by checking that the vtbl pointer matches
2200 bool Method::is_valid_method(const Method* m) {
2201 if (m == NULL) {
2202 return false;
2203 } else if ((intptr_t(m) & (wordSize-1)) != 0) {
2204 // Quick sanity check on pointer.
2205 return false;
2206 } else if (m->is_shared()) {
2207 return MetaspaceShared::is_valid_shared_method(m);
2208 } else if (Metaspace::contains_non_shared(m)) {
2209 return has_method_vptr((const void*)m);
2210 } else {
2211 return false;
2212 }
2213 }
2214
2215 #ifndef PRODUCT
2216 void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
2217 out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2218 }
2219 #endif // PRODUCT
2220
2221
2222 // Printing
2223
2224 #ifndef PRODUCT
2225
2226 void Method::print_on(outputStream* st) const {
2227 ResourceMark rm;
2228 assert(is_method(), "must be method");
2229 st->print_cr("%s", internal_name());
2230 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2231 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2232 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2233 constants()->print_value_on(st); st->cr();
2234 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2235 st->print (" - name: "); name()->print_value_on(st); st->cr();
2236 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2237 st->print_cr(" - max stack: %d", max_stack());
2238 st->print_cr(" - max locals: %d", max_locals());
2239 st->print_cr(" - size of params: %d", size_of_parameters());
2240 st->print_cr(" - method size: %d", method_size());
2241 if (intrinsic_id() != vmIntrinsics::_none)
2242 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2243 if (highest_comp_level() != CompLevel_none)
2244 st->print_cr(" - highest level: %d", highest_comp_level());
2245 st->print_cr(" - vtable index: %d", _vtable_index);
2246 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2247 st->print( " - adapters: ");
2248 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2249 if (a == NULL)
2250 st->print_cr(INTPTR_FORMAT, p2i(a));
2251 else
2252 a->print_adapter_on(st);
2253 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2254 st->print_cr(" - code size: %d", code_size());
2255 if (code_size() != 0) {
2256 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2257 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2258 }
2259 if (method_data() != NULL) {
2260 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2261 }
2262 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2263 if (checked_exceptions_length() > 0) {
2264 CheckedExceptionElement* table = checked_exceptions_start();
2265 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2266 if (Verbose) {
2267 for (int i = 0; i < checked_exceptions_length(); i++) {
2268 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2269 }
2270 }
2271 }
2272 if (has_linenumber_table()) {
2273 u_char* table = compressed_linenumber_table();
2274 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2275 if (Verbose) {
2276 CompressedLineNumberReadStream stream(table);
2277 while (stream.read_pair()) {
2278 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2279 }
2280 }
2281 }
2282 st->print_cr(" - localvar length: %d", localvariable_table_length());
2283 if (localvariable_table_length() > 0) {
2284 LocalVariableTableElement* table = localvariable_table_start();
2285 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2286 if (Verbose) {
2287 for (int i = 0; i < localvariable_table_length(); i++) {
2288 int bci = table[i].start_bci;
2289 int len = table[i].length;
2290 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2291 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2292 int slot = table[i].slot;
2293 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2294 }
2295 }
2296 }
2297 if (code() != NULL) {
2298 st->print (" - compiled code: ");
2299 code()->print_value_on(st);
2300 }
2301 if (is_native()) {
2302 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2303 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2304 }
2305 }
2306
2307 void Method::print_linkage_flags(outputStream* st) {
2308 access_flags().print_on(st);
2309 if (is_default_method()) {
2310 st->print("default ");
2311 }
2312 if (is_overpass()) {
2313 st->print("overpass ");
2314 }
2315 }
2316 #endif //PRODUCT
2317
2318 void Method::print_value_on(outputStream* st) const {
2319 assert(is_method(), "must be method");
2320 st->print("%s", internal_name());
2321 print_address_on(st);
2322 st->print(" ");
2323 name()->print_value_on(st);
2324 st->print(" ");
2325 signature()->print_value_on(st);
2326 st->print(" in ");
2327 method_holder()->print_value_on(st);
2328 if (WizardMode) st->print("#%d", _vtable_index);
2329 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2330 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2331 }
2332
2333 #if INCLUDE_SERVICES
2334 // Size Statistics
2335 void Method::collect_statistics(KlassSizeStats *sz) const {
2336 int mysize = sz->count(this);
2337 sz->_method_bytes += mysize;
2338 sz->_method_all_bytes += mysize;
2339 sz->_rw_bytes += mysize;
2340
2341 if (constMethod()) {
2342 constMethod()->collect_statistics(sz);
2343 }
2344 if (method_data()) {
2345 method_data()->collect_statistics(sz);
2346 }
2347 }
2348 #endif // INCLUDE_SERVICES
2349
2350 // LogTouchedMethods and PrintTouchedMethods
2351
2352 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2353 // the Method may be garbage collected. Let's roll our own hash table.
2354 class TouchedMethodRecord : CHeapObj<mtTracing> {
2355 public:
2356 // It's OK to store Symbols here because they will NOT be GC'ed if
2357 // LogTouchedMethods is enabled.
2358 TouchedMethodRecord* _next;
2359 Symbol* _class_name;
2360 Symbol* _method_name;
2361 Symbol* _method_signature;
2362 };
2363
2364 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2365 static TouchedMethodRecord** _touched_method_table = NULL;
2366
2367 void Method::log_touched(TRAPS) {
2368
2369 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2370 Symbol* my_class = klass_name();
2371 Symbol* my_name = name();
2372 Symbol* my_sig = signature();
2373
2374 unsigned int hash = my_class->identity_hash() +
2375 my_name->identity_hash() +
2376 my_sig->identity_hash();
2377 juint index = juint(hash) % table_size;
2378
2379 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2380 if (_touched_method_table == NULL) {
2381 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2382 mtTracing, CURRENT_PC);
2383 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2384 }
2385
2386 TouchedMethodRecord* ptr = _touched_method_table[index];
2387 while (ptr) {
2388 if (ptr->_class_name == my_class &&
2389 ptr->_method_name == my_name &&
2390 ptr->_method_signature == my_sig) {
2391 return;
2392 }
2393 if (ptr->_next == NULL) break;
2394 ptr = ptr->_next;
2395 }
2396 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2397 my_class->increment_refcount();
2398 my_name->increment_refcount();
2399 my_sig->increment_refcount();
2400 nptr->_class_name = my_class;
2401 nptr->_method_name = my_name;
2402 nptr->_method_signature = my_sig;
2403 nptr->_next = NULL;
2404
2405 if (ptr == NULL) {
2406 // first
2407 _touched_method_table[index] = nptr;
2408 } else {
2409 ptr->_next = nptr;
2410 }
2411 }
2412
2413 void Method::print_touched_methods(outputStream* out) {
2414 MutexLocker ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2415 out->print_cr("# Method::print_touched_methods version 1");
2416 if (_touched_method_table) {
2417 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2418 TouchedMethodRecord* ptr = _touched_method_table[i];
2419 while(ptr) {
2420 ptr->_class_name->print_symbol_on(out); out->print(".");
2421 ptr->_method_name->print_symbol_on(out); out->print(":");
2422 ptr->_method_signature->print_symbol_on(out); out->cr();
2423 ptr = ptr->_next;
2424 }
2425 }
2426 }
2427 }
2428
2429 // Verification
2430
2431 void Method::verify_on(outputStream* st) {
2432 guarantee(is_method(), "object must be method");
2433 guarantee(constants()->is_constantPool(), "should be constant pool");
2434 MethodData* md = method_data();
2435 guarantee(md == NULL ||
2436 md->is_methodData(), "should be method data");
2437 }