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