1 /*
2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/metadataOnStackMark.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "code/codeCache.hpp"
29 #include "code/debugInfoRec.hpp"
30 #include "gc/shared/collectedHeap.inline.hpp"
31 #include "gc/shared/gcLocker.hpp"
32 #include "gc/shared/generation.hpp"
33 #include "interpreter/bytecodeStream.hpp"
34 #include "interpreter/bytecodeTracer.hpp"
35 #include "interpreter/bytecodes.hpp"
36 #include "interpreter/interpreter.hpp"
37 #include "interpreter/oopMapCache.hpp"
38 #include "memory/heapInspection.hpp"
39 #include "memory/metadataFactory.hpp"
40 #include "memory/metaspaceShared.hpp"
41 #include "memory/oopFactory.hpp"
42 #include "memory/resourceArea.hpp"
43 #include "oops/constMethod.hpp"
44 #include "oops/method.hpp"
45 #include "oops/methodData.hpp"
46 #include "oops/objArrayOop.inline.hpp"
47 #include "oops/oop.inline.hpp"
48 #include "oops/symbol.hpp"
49 #include "oops/valueKlass.hpp"
50 #include "prims/jvmtiExport.hpp"
51 #include "prims/methodHandles.hpp"
52 #include "prims/nativeLookup.hpp"
53 #include "runtime/arguments.hpp"
54 #include "runtime/compilationPolicy.hpp"
55 #include "runtime/frame.inline.hpp"
56 #include "runtime/handles.inline.hpp"
57 #include "runtime/init.hpp"
58 #include "runtime/orderAccess.inline.hpp"
59 #include "runtime/relocator.hpp"
60 #include "runtime/sharedRuntime.hpp"
61 #include "runtime/signature.hpp"
62 #include "utilities/quickSort.hpp"
63 #include "utilities/xmlstream.hpp"
64
65 // Implementation of Method
66
67 Method* Method::allocate(ClassLoaderData* loader_data,
68 int byte_code_size,
69 AccessFlags access_flags,
70 InlineTableSizes* sizes,
71 ConstMethod::MethodType method_type,
72 TRAPS) {
73 assert(!access_flags.is_native() || byte_code_size == 0,
74 "native methods should not contain byte codes");
75 ConstMethod* cm = ConstMethod::allocate(loader_data,
76 byte_code_size,
77 sizes,
78 method_type,
79 CHECK_NULL);
80 int size = Method::size(access_flags.is_native());
81 return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
82 }
83
84 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
85 NoSafepointVerifier no_safepoint;
86 set_constMethod(xconst);
87 set_access_flags(access_flags);
88 set_intrinsic_id(vmIntrinsics::_none);
89 set_force_inline(false);
90 set_hidden(false);
91 set_dont_inline(false);
92 set_has_injected_profile(false);
93 set_method_data(NULL);
94 clear_method_counters();
95 set_vtable_index(Method::garbage_vtable_index);
96
97 // Fix and bury in Method*
98 set_interpreter_entry(NULL); // sets i2i entry and from_int
99 set_adapter_entry(NULL);
100 clear_code(false /* don't need a lock */); // from_c/from_i get set to c2i/i2i
101
102 if (access_flags.is_native()) {
103 clear_native_function();
104 set_signature_handler(NULL);
105 }
106
107 NOT_PRODUCT(set_compiled_invocation_count(0);)
108 }
109
110 // Release Method*. The nmethod will be gone when we get here because
111 // we've walked the code cache.
112 void Method::deallocate_contents(ClassLoaderData* loader_data) {
113 MetadataFactory::free_metadata(loader_data, constMethod());
114 set_constMethod(NULL);
115 MetadataFactory::free_metadata(loader_data, method_data());
116 set_method_data(NULL);
117 MetadataFactory::free_metadata(loader_data, method_counters());
118 clear_method_counters();
119 // The nmethod will be gone when we get here.
120 if (code() != NULL) _code = NULL;
121 }
122
123 address Method::get_i2c_entry() {
124 assert(adapter() != NULL, "must have");
125 return adapter()->get_i2c_entry();
126 }
127
128 address Method::get_c2i_entry() {
129 assert(adapter() != NULL, "must have");
130 return adapter()->get_c2i_entry();
131 }
132
133 address Method::get_c2i_unverified_entry() {
134 assert(adapter() != NULL, "must have");
135 return adapter()->get_c2i_unverified_entry();
136 }
137
138 char* Method::name_and_sig_as_C_string() const {
139 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
140 }
141
142 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
143 return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
144 }
145
146 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
147 const char* klass_name = klass->external_name();
148 int klass_name_len = (int)strlen(klass_name);
149 int method_name_len = method_name->utf8_length();
150 int len = klass_name_len + 1 + method_name_len + signature->utf8_length();
151 char* dest = NEW_RESOURCE_ARRAY(char, len + 1);
152 strcpy(dest, klass_name);
153 dest[klass_name_len] = '.';
154 strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
155 strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
156 dest[len] = 0;
157 return dest;
158 }
159
160 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
161 Symbol* klass_name = klass->name();
162 klass_name->as_klass_external_name(buf, size);
163 int len = (int)strlen(buf);
164
165 if (len < size - 1) {
166 buf[len++] = '.';
167
168 method_name->as_C_string(&(buf[len]), size - len);
169 len = (int)strlen(buf);
170
171 signature->as_C_string(&(buf[len]), size - len);
172 }
173
174 return buf;
175 }
176
177 int Method::fast_exception_handler_bci_for(methodHandle mh, Klass* ex_klass, int throw_bci, TRAPS) {
178 // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
179 // access exception table
180 ExceptionTable table(mh());
181 int length = table.length();
182 // iterate through all entries sequentially
183 constantPoolHandle pool(THREAD, mh->constants());
184 for (int i = 0; i < length; i ++) {
185 //reacquire the table in case a GC happened
186 ExceptionTable table(mh());
187 int beg_bci = table.start_pc(i);
188 int end_bci = table.end_pc(i);
189 assert(beg_bci <= end_bci, "inconsistent exception table");
190 if (beg_bci <= throw_bci && throw_bci < end_bci) {
191 // exception handler bci range covers throw_bci => investigate further
192 int handler_bci = table.handler_pc(i);
193 int klass_index = table.catch_type_index(i);
194 if (klass_index == 0) {
195 return handler_bci;
196 } else if (ex_klass == NULL) {
197 return handler_bci;
198 } else {
199 // we know the exception class => get the constraint class
200 // this may require loading of the constraint class; if verification
201 // fails or some other exception occurs, return handler_bci
202 Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
203 assert(k != NULL, "klass not loaded");
204 if (ex_klass->is_subtype_of(k)) {
205 return handler_bci;
206 }
207 }
208 }
209 }
210
211 return -1;
212 }
213
214 void Method::mask_for(int bci, InterpreterOopMap* mask) {
215
216 Thread* myThread = Thread::current();
217 methodHandle h_this(myThread, this);
218 #if defined(ASSERT) && !INCLUDE_JVMCI
219 bool has_capability = myThread->is_VM_thread() ||
220 myThread->is_ConcurrentGC_thread() ||
221 myThread->is_GC_task_thread();
222
223 if (!has_capability) {
224 if (!VerifyStack && !VerifyLastFrame) {
225 // verify stack calls this outside VM thread
226 warning("oopmap should only be accessed by the "
227 "VM, GC task or CMS threads (or during debugging)");
228 InterpreterOopMap local_mask;
229 method_holder()->mask_for(h_this, bci, &local_mask);
230 local_mask.print();
231 }
232 }
233 #endif
234 method_holder()->mask_for(h_this, bci, mask);
235 return;
236 }
237
238
239 int Method::bci_from(address bcp) const {
240 if (is_native() && bcp == 0) {
241 return 0;
242 }
243 #ifdef ASSERT
244 {
245 ResourceMark rm;
246 assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
247 "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
248 p2i(bcp), name_and_sig_as_C_string());
249 }
250 #endif
251 return bcp - code_base();
252 }
253
254
255 int Method::validate_bci(int bci) const {
256 return (bci == 0 || bci < code_size()) ? bci : -1;
257 }
258
259 // Return bci if it appears to be a valid bcp
260 // Return -1 otherwise.
261 // Used by profiling code, when invalid data is a possibility.
262 // The caller is responsible for validating the Method* itself.
263 int Method::validate_bci_from_bcp(address bcp) const {
264 // keep bci as -1 if not a valid bci
265 int bci = -1;
266 if (bcp == 0 || bcp == code_base()) {
267 // code_size() may return 0 and we allow 0 here
268 // the method may be native
269 bci = 0;
270 } else if (contains(bcp)) {
271 bci = bcp - code_base();
272 }
273 // Assert that if we have dodged any asserts, bci is negative.
274 assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
275 return bci;
276 }
277
278 address Method::bcp_from(int bci) const {
279 assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()),
280 "illegal bci: %d for %s method", bci, is_native() ? "native" : "non-native");
281 address bcp = code_base() + bci;
282 assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
283 return bcp;
284 }
285
286 address Method::bcp_from(address bcp) const {
287 if (is_native() && bcp == NULL) {
288 return code_base();
289 } else {
290 return bcp;
291 }
292 }
293
294 int Method::size(bool is_native) {
295 // If native, then include pointers for native_function and signature_handler
296 int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
297 int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
298 return align_metadata_size(header_size() + extra_words);
299 }
300
301
302 Symbol* Method::klass_name() const {
303 return method_holder()->name();
304 }
305
306
307 // Attempt to return method oop to original state. Clear any pointers
308 // (to objects outside the shared spaces). We won't be able to predict
309 // where they should point in a new JVM. Further initialize some
310 // entries now in order allow them to be write protected later.
311
312 void Method::remove_unshareable_info() {
313 unlink_method();
314 }
315
316 void Method::set_vtable_index(int index) {
317 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
318 // At runtime initialize_vtable is rerun as part of link_class_impl()
319 // for a shared class loaded by the non-boot loader to obtain the loader
320 // constraints based on the runtime classloaders' context.
321 return; // don't write into the shared class
322 } else {
323 _vtable_index = index;
324 }
325 }
326
327 void Method::set_itable_index(int index) {
328 if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
329 // At runtime initialize_itable is rerun as part of link_class_impl()
330 // for a shared class loaded by the non-boot loader to obtain the loader
331 // constraints based on the runtime classloaders' context. The dumptime
332 // itable index should be the same as the runtime index.
333 assert(_vtable_index == itable_index_max - index,
334 "archived itable index is different from runtime index");
335 return; // don’t write into the shared class
336 } else {
337 _vtable_index = itable_index_max - index;
338 }
339 assert(valid_itable_index(), "");
340 }
341
342
343
344 bool Method::was_executed_more_than(int n) {
345 // Invocation counter is reset when the Method* is compiled.
346 // If the method has compiled code we therefore assume it has
347 // be excuted more than n times.
348 if (is_accessor() || is_empty_method() || (code() != NULL)) {
349 // interpreter doesn't bump invocation counter of trivial methods
350 // compiler does not bump invocation counter of compiled methods
351 return true;
352 }
353 else if ((method_counters() != NULL &&
354 method_counters()->invocation_counter()->carry()) ||
355 (method_data() != NULL &&
356 method_data()->invocation_counter()->carry())) {
357 // The carry bit is set when the counter overflows and causes
358 // a compilation to occur. We don't know how many times
359 // the counter has been reset, so we simply assume it has
360 // been executed more than n times.
361 return true;
362 } else {
363 return invocation_count() > n;
364 }
365 }
366
367 void Method::print_invocation_count() {
368 if (is_static()) tty->print("static ");
369 if (is_final()) tty->print("final ");
370 if (is_synchronized()) tty->print("synchronized ");
371 if (is_native()) tty->print("native ");
372 tty->print("%s::", method_holder()->external_name());
373 name()->print_symbol_on(tty);
374 signature()->print_symbol_on(tty);
375
376 if (WizardMode) {
377 // dump the size of the byte codes
378 tty->print(" {%d}", code_size());
379 }
380 tty->cr();
381
382 tty->print_cr (" interpreter_invocation_count: %8d ", interpreter_invocation_count());
383 tty->print_cr (" invocation_counter: %8d ", invocation_count());
384 tty->print_cr (" backedge_counter: %8d ", backedge_count());
385 #ifndef PRODUCT
386 if (CountCompiledCalls) {
387 tty->print_cr (" compiled_invocation_count: %8d ", compiled_invocation_count());
388 }
389 #endif
390 }
391
392 // Build a MethodData* object to hold information about this method
393 // collected in the interpreter.
394 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
395 // Do not profile the method if metaspace has hit an OOM previously
396 // allocating profiling data. Callers clear pending exception so don't
397 // add one here.
398 if (ClassLoaderDataGraph::has_metaspace_oom()) {
399 return;
400 }
401
402 // Grab a lock here to prevent multiple
403 // MethodData*s from being created.
404 MutexLocker ml(MethodData_lock, THREAD);
405 if (method->method_data() == NULL) {
406 ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
407 MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
408 if (HAS_PENDING_EXCEPTION) {
409 CompileBroker::log_metaspace_failure();
410 ClassLoaderDataGraph::set_metaspace_oom(true);
411 return; // return the exception (which is cleared)
412 }
413
414 method->set_method_data(method_data);
415 if (PrintMethodData && (Verbose || WizardMode)) {
416 ResourceMark rm(THREAD);
417 tty->print("build_interpreter_method_data for ");
418 method->print_name(tty);
419 tty->cr();
420 // At the end of the run, the MDO, full of data, will be dumped.
421 }
422 }
423 }
424
425 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
426 // Do not profile the method if metaspace has hit an OOM previously
427 if (ClassLoaderDataGraph::has_metaspace_oom()) {
428 return NULL;
429 }
430
431 methodHandle mh(m);
432 MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
433 if (HAS_PENDING_EXCEPTION) {
434 CompileBroker::log_metaspace_failure();
435 ClassLoaderDataGraph::set_metaspace_oom(true);
436 return NULL; // return the exception (which is cleared)
437 }
438 if (!mh->init_method_counters(counters)) {
439 MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
440 }
441
442 if (LogTouchedMethods) {
443 mh->log_touched(CHECK_NULL);
444 }
445
446 return mh->method_counters();
447 }
448
449 void Method::cleanup_inline_caches() {
450 // The current system doesn't use inline caches in the interpreter
451 // => nothing to do (keep this method around for future use)
452 }
453
454
455 int Method::extra_stack_words() {
456 // not an inline function, to avoid a header dependency on Interpreter
457 return extra_stack_entries() * Interpreter::stackElementSize;
458 }
459
460
461 void Method::compute_size_of_parameters(Thread *thread) {
462 ArgumentSizeComputer asc(signature());
463 set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
464 }
465
466 BasicType Method::result_type() const {
467 ResultTypeFinder rtf(signature());
468 return rtf.type();
469 }
470
471 #ifdef ASSERT
472 // ValueKlass the method is declared to return. This must not
473 // safepoint as it is called with references live on the stack at
474 // locations the GC is unaware of.
475 ValueKlass* Method::returned_value_type(Thread* thread) const {
476 assert(is_returning_vt(), "method return type should be value type");
477 SignatureStream ss(signature());
478 while (!ss.at_return_type()) {
479 ss.next();
480 }
481 Handle class_loader(thread, method_holder()->class_loader());
482 Handle protection_domain(thread, method_holder()->protection_domain());
483 Klass* k = NULL;
484 {
485 NoSafepointVerifier nsv;
486 k = ss.as_klass(class_loader, protection_domain, SignatureStream::ReturnNull, thread);
487 }
488 assert(k != NULL && !thread->has_pending_exception(), "can't resolve klass");
489 return ValueKlass::cast(k);
490 }
491 #endif
492
493 bool Method::is_empty_method() const {
494 return code_size() == 1
495 && *code_base() == Bytecodes::_return;
496 }
497
498
499 bool Method::is_vanilla_constructor() const {
500 // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
501 // which only calls the superclass vanilla constructor and possibly does stores of
502 // zero constants to local fields:
503 //
504 // aload_0
505 // invokespecial
506 // indexbyte1
507 // indexbyte2
508 //
509 // followed by an (optional) sequence of:
510 //
511 // aload_0
512 // aconst_null / iconst_0 / fconst_0 / dconst_0
513 // putfield
514 // indexbyte1
515 // indexbyte2
516 //
517 // followed by:
518 //
519 // return
520
521 assert(name() == vmSymbols::object_initializer_name(), "Should only be called for default constructors");
522 assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
523 int size = code_size();
524 // Check if size match
525 if (size == 0 || size % 5 != 0) return false;
526 address cb = code_base();
527 int last = size - 1;
528 if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
529 // Does not call superclass default constructor
530 return false;
531 }
532 // Check optional sequence
533 for (int i = 4; i < last; i += 5) {
534 if (cb[i] != Bytecodes::_aload_0) return false;
535 if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
536 if (cb[i+2] != Bytecodes::_putfield) return false;
537 }
538 return true;
539 }
540
541
542 bool Method::compute_has_loops_flag() {
543 BytecodeStream bcs(this);
544 Bytecodes::Code bc;
545
546 while ((bc = bcs.next()) >= 0) {
547 switch( bc ) {
548 case Bytecodes::_ifeq:
549 case Bytecodes::_ifnull:
550 case Bytecodes::_iflt:
551 case Bytecodes::_ifle:
552 case Bytecodes::_ifne:
553 case Bytecodes::_ifnonnull:
554 case Bytecodes::_ifgt:
555 case Bytecodes::_ifge:
556 case Bytecodes::_if_icmpeq:
557 case Bytecodes::_if_icmpne:
558 case Bytecodes::_if_icmplt:
559 case Bytecodes::_if_icmpgt:
560 case Bytecodes::_if_icmple:
561 case Bytecodes::_if_icmpge:
562 case Bytecodes::_if_acmpeq:
563 case Bytecodes::_if_acmpne:
564 case Bytecodes::_goto:
565 case Bytecodes::_jsr:
566 if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
567 break;
568
569 case Bytecodes::_goto_w:
570 case Bytecodes::_jsr_w:
571 if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
572 break;
573 }
574 }
575 _access_flags.set_loops_flag_init();
576 return _access_flags.has_loops();
577 }
578
579 bool Method::is_final_method(AccessFlags class_access_flags) const {
580 // or "does_not_require_vtable_entry"
581 // default method or overpass can occur, is not final (reuses vtable entry)
582 // private methods in classes get vtable entries for backward class compatibility.
583 if (is_overpass() || is_default_method()) return false;
584 return is_final() || class_access_flags.is_final();
585 }
586
587 bool Method::is_final_method() const {
588 return is_final_method(method_holder()->access_flags());
589 }
590
591 bool Method::is_default_method() const {
592 if (method_holder() != NULL &&
593 method_holder()->is_interface() &&
594 !is_abstract() && !is_private()) {
595 return true;
596 } else {
597 return false;
598 }
599 }
600
601 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
602 if (is_final_method(class_access_flags)) return true;
603 #ifdef ASSERT
604 ResourceMark rm;
605 bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
606 if (class_access_flags.is_interface()) {
607 assert(is_nonv == is_static() || is_nonv == is_private(),
608 "nonvirtual unexpected for non-static, non-private: %s",
609 name_and_sig_as_C_string());
610 }
611 #endif
612 assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
613 return vtable_index() == nonvirtual_vtable_index;
614 }
615
616 bool Method::can_be_statically_bound() const {
617 return can_be_statically_bound(method_holder()->access_flags());
618 }
619
620 bool Method::is_accessor() const {
621 return is_getter() || is_setter();
622 }
623
624 bool Method::is_getter() const {
625 if (code_size() != 5) return false;
626 if (size_of_parameters() != 1) return false;
627 if (java_code_at(0) != Bytecodes::_aload_0) return false;
628 if (java_code_at(1) != Bytecodes::_getfield) return false;
629 switch (java_code_at(4)) {
630 case Bytecodes::_ireturn:
631 case Bytecodes::_lreturn:
632 case Bytecodes::_freturn:
633 case Bytecodes::_dreturn:
634 case Bytecodes::_areturn:
635 break;
636 default:
637 return false;
638 }
639 return true;
640 }
641
642 bool Method::is_setter() const {
643 if (code_size() != 6) return false;
644 if (java_code_at(0) != Bytecodes::_aload_0) return false;
645 switch (java_code_at(1)) {
646 case Bytecodes::_iload_1:
647 case Bytecodes::_aload_1:
648 case Bytecodes::_fload_1:
649 if (size_of_parameters() != 2) return false;
650 break;
651 case Bytecodes::_dload_1:
652 case Bytecodes::_lload_1:
653 if (size_of_parameters() != 3) return false;
654 break;
655 default:
656 return false;
657 }
658 if (java_code_at(2) != Bytecodes::_putfield) return false;
659 if (java_code_at(5) != Bytecodes::_return) return false;
660 return true;
661 }
662
663 bool Method::is_constant_getter() const {
664 int last_index = code_size() - 1;
665 // Check if the first 1-3 bytecodes are a constant push
666 // and the last bytecode is a return.
667 return (2 <= code_size() && code_size() <= 4 &&
668 Bytecodes::is_const(java_code_at(0)) &&
669 Bytecodes::length_for(java_code_at(0)) == last_index &&
670 Bytecodes::is_return(java_code_at(last_index)));
671 }
672
673 bool Method::is_initializer() const {
674 return is_object_initializer() || is_static_initializer();
675 }
676
677 bool Method::has_valid_initializer_flags() const {
678 return (is_static() ||
679 method_holder()->major_version() < 51);
680 }
681
682 bool Method::is_static_initializer() const {
683 // For classfiles version 51 or greater, ensure that the clinit method is
684 // static. Non-static methods with the name "<clinit>" are not static
685 // initializers. (older classfiles exempted for backward compatibility)
686 return name() == vmSymbols::class_initializer_name() &&
687 has_valid_initializer_flags();
688 }
689
690 bool Method::is_object_initializer() const {
691 return name() == vmSymbols::object_initializer_name();
692 }
693
694 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
695 int length = method->checked_exceptions_length();
696 if (length == 0) { // common case
697 return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
698 } else {
699 methodHandle h_this(THREAD, method);
700 objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
701 objArrayHandle mirrors (THREAD, m_oop);
702 for (int i = 0; i < length; i++) {
703 CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
704 Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
705 assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
706 mirrors->obj_at_put(i, k->java_mirror());
707 }
708 return mirrors;
709 }
710 };
711
712
713 int Method::line_number_from_bci(int bci) const {
714 if (bci == SynchronizationEntryBCI) bci = 0;
715 assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
716 int best_bci = 0;
717 int best_line = -1;
718
719 if (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 clear_code();
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::clear_code(bool acquire_lock /* = true */) {
931 MutexLockerEx pl(acquire_lock ? Patching_lock : NULL, Mutex::_no_safepoint_check_flag);
932 // this may be NULL if c2i adapters have not been made yet
933 // Only should happen at allocate time.
934 if (adapter() == NULL) {
935 _from_compiled_entry = NULL;
936 } else {
937 _from_compiled_entry = adapter()->get_c2i_entry();
938 }
939 OrderAccess::storestore();
940 _from_interpreted_entry = _i2i_entry;
941 OrderAccess::storestore();
942 _code = NULL;
943 }
944
945 #if INCLUDE_CDS
946 // Called by class data sharing to remove any entry points (which are not shared)
947 void Method::unlink_method() {
948 _code = NULL;
949
950 assert(DumpSharedSpaces, "dump time only");
951 // Set the values to what they should be at run time. Note that
952 // this Method can no longer be executed during dump time.
953 _i2i_entry = Interpreter::entry_for_cds_method(this);
954 _from_interpreted_entry = _i2i_entry;
955
956 if (is_native()) {
957 *native_function_addr() = NULL;
958 set_signature_handler(NULL);
959 }
960 NOT_PRODUCT(set_compiled_invocation_count(0);)
961
962 CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
963 constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
964 _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
965 assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
966
967
968 // In case of DumpSharedSpaces, _method_data should always be NULL.
969 assert(_method_data == NULL, "unexpected method data?");
970
971 set_method_data(NULL);
972 clear_method_counters();
973 }
974 #endif
975
976 /****************************************************************************
977 // The following illustrates how the entries work for CDS shared Methods:
978 //
979 // Our goal is to delay writing into a shared Method until it's compiled.
980 // Hence, we want to determine the initial values for _i2i_entry,
981 // _from_interpreted_entry and _from_compiled_entry during CDS dump time.
982 //
983 // In this example, both Methods A and B have the _i2i_entry of "zero_locals".
984 // They also have similar signatures so that they will share the same
985 // AdapterHandlerEntry.
986 //
987 // _adapter_trampoline points to a fixed location in the RW section of
988 // the CDS archive. This location initially contains a NULL pointer. When the
989 // first of method A or B is linked, an AdapterHandlerEntry is allocated
990 // dynamically, and its c2i/i2c entries are generated.
991 //
992 // _i2i_entry and _from_interpreted_entry initially points to the same
993 // (fixed) location in the CODE section of the CDS archive. This contains
994 // an unconditional branch to the actual entry for "zero_locals", which is
995 // generated at run time and may be on an arbitrary address. Thus, the
996 // unconditional branch is also generated at run time to jump to the correct
997 // address.
998 //
999 // Similarly, _from_compiled_entry points to a fixed address in the CODE
1000 // section. This address has enough space for an unconditional branch
1001 // instruction, and is initially zero-filled. After the AdapterHandlerEntry is
1002 // initialized, and the address for the actual c2i_entry is known, we emit a
1003 // branch instruction here to branch to the actual c2i_entry.
1004 //
1005 // The effect of the extra branch on the i2i and c2i entries is negligible.
1006 //
1007 // The reason for putting _adapter_trampoline in RO is many shared Methods
1008 // share the same AdapterHandlerEntry, so we can save space in the RW section
1009 // by having the extra indirection.
1010
1011
1012 [Method A: RW]
1013 _constMethod ----> [ConstMethod: RO]
1014 _adapter_trampoline -----------+
1015 |
1016 _i2i_entry (same value as method B) |
1017 _from_interpreted_entry (same value as method B) |
1018 _from_compiled_entry (same value as method B) |
1019 |
1020 |
1021 [Method B: RW] +--------+
1022 _constMethod ----> [ConstMethod: RO] |
1023 _adapter_trampoline --+--->(AdapterHandlerEntry* ptr: RW)-+
1024 |
1025 +-------------------------------+
1026 |
1027 +----> [AdapterHandlerEntry] (allocated at run time)
1028 _fingerprint
1029 _c2i_entry ---------------------------------+->[c2i entry..]
1030 _i2i_entry -------------+ _i2c_entry ---------------+-> [i2c entry..] |
1031 _from_interpreted_entry | _c2i_unverified_entry | |
1032 | | | |
1033 | | (_cds_entry_table: CODE) | |
1034 | +->[0]: jmp _entry_table[0] --> (i2i_entry_for "zero_locals") | |
1035 | | (allocated at run time) | |
1036 | | ... [asm code ...] | |
1037 +-[not compiled]-+ [n]: jmp _entry_table[n] | |
1038 | | |
1039 | | |
1040 +-[compiled]-------------------------------------------------------------------+ |
1041 |
1042 _from_compiled_entry------------> (_c2i_entry_trampoline: CODE) |
1043 [jmp c2i_entry] ------------------------------------------------------+
1044
1045 ***/
1046
1047 // Called when the method_holder is getting linked. Setup entrypoints so the method
1048 // is ready to be called from interpreter, compiler, and vtables.
1049 void Method::link_method(const methodHandle& h_method, TRAPS) {
1050 // If the code cache is full, we may reenter this function for the
1051 // leftover methods that weren't linked.
1052 if (is_shared()) {
1053 address entry = Interpreter::entry_for_cds_method(h_method);
1054 assert(entry != NULL && entry == _i2i_entry,
1055 "should be correctly set during dump time");
1056 if (adapter() != NULL) {
1057 return;
1058 }
1059 assert(entry == _from_interpreted_entry,
1060 "should be correctly set during dump time");
1061 } else if (_i2i_entry != NULL) {
1062 return;
1063 }
1064 assert( _code == NULL, "nothing compiled yet" );
1065
1066 // Setup interpreter entrypoint
1067 assert(this == h_method(), "wrong h_method()" );
1068
1069 if (!is_shared()) {
1070 assert(adapter() == NULL, "init'd to NULL");
1071 address entry = Interpreter::entry_for_method(h_method);
1072 assert(entry != NULL, "interpreter entry must be non-null");
1073 // Sets both _i2i_entry and _from_interpreted_entry
1074 set_interpreter_entry(entry);
1075 }
1076
1077 // Don't overwrite already registered native entries.
1078 if (is_native() && !has_native_function()) {
1079 set_native_function(
1080 SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
1081 !native_bind_event_is_interesting);
1082 }
1083
1084 // Setup compiler entrypoint. This is made eagerly, so we do not need
1085 // special handling of vtables. An alternative is to make adapters more
1086 // lazily by calling make_adapter() from from_compiled_entry() for the
1087 // normal calls. For vtable calls life gets more complicated. When a
1088 // call-site goes mega-morphic we need adapters in all methods which can be
1089 // called from the vtable. We need adapters on such methods that get loaded
1090 // later. Ditto for mega-morphic itable calls. If this proves to be a
1091 // problem we'll make these lazily later.
1092 (void) make_adapters(h_method, CHECK);
1093
1094 // ONLY USE the h_method now as make_adapter may have blocked
1095
1096 }
1097
1098 address Method::make_adapters(methodHandle mh, TRAPS) {
1099 // Adapters for compiled code are made eagerly here. They are fairly
1100 // small (generally < 100 bytes) and quick to make (and cached and shared)
1101 // so making them eagerly shouldn't be too expensive.
1102 AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1103 if (adapter == NULL ) {
1104 if (!is_init_completed()) {
1105 // Don't throw exceptions during VM initialization because java.lang.* classes
1106 // might not have been initialized, causing problems when constructing the
1107 // Java exception object.
1108 vm_exit_during_initialization("Out of space in CodeCache for adapters");
1109 } else {
1110 THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1111 }
1112 }
1113
1114 if (mh->is_shared()) {
1115 assert(mh->adapter() == adapter, "must be");
1116 assert(mh->_from_compiled_entry != NULL, "must be");
1117 } else {
1118 mh->set_adapter_entry(adapter);
1119 mh->_from_compiled_entry = adapter->get_c2i_entry();
1120 }
1121 return adapter->get_c2i_entry();
1122 }
1123
1124 void Method::restore_unshareable_info(TRAPS) {
1125 assert(is_method() && is_valid_method(), "ensure C++ vtable is restored");
1126
1127 // Since restore_unshareable_info can be called more than once for a method, don't
1128 // redo any work.
1129 if (adapter() == NULL) {
1130 methodHandle mh(THREAD, this);
1131 link_method(mh, CHECK);
1132 }
1133 }
1134
1135 volatile address Method::from_compiled_entry_no_trampoline() const {
1136 nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
1137 if (code) {
1138 return code->verified_entry_point();
1139 } else {
1140 return adapter()->get_c2i_entry();
1141 }
1142 }
1143
1144 // The verified_code_entry() must be called when a invoke is resolved
1145 // on this method.
1146
1147 // It returns the compiled code entry point, after asserting not null.
1148 // This function is called after potential safepoints so that nmethod
1149 // or adapter that it points to is still live and valid.
1150 // This function must not hit a safepoint!
1151 address Method::verified_code_entry() {
1152 debug_only(NoSafepointVerifier nsv;)
1153 assert(_from_compiled_entry != NULL, "must be set");
1154 return _from_compiled_entry;
1155 }
1156
1157 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1158 // (could be racing a deopt).
1159 // Not inline to avoid circular ref.
1160 bool Method::check_code() const {
1161 // cached in a register or local. There's a race on the value of the field.
1162 CompiledMethod *code = (CompiledMethod *)OrderAccess::load_ptr_acquire(&_code);
1163 return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1164 }
1165
1166 // Install compiled code. Instantly it can execute.
1167 void Method::set_code(methodHandle mh, CompiledMethod *code) {
1168 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1169 assert( code, "use clear_code to remove code" );
1170 assert( mh->check_code(), "" );
1171
1172 guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1173
1174 // These writes must happen in this order, because the interpreter will
1175 // directly jump to from_interpreted_entry which jumps to an i2c adapter
1176 // which jumps to _from_compiled_entry.
1177 mh->_code = code; // Assign before allowing compiled code to exec
1178
1179 int comp_level = code->comp_level();
1180 // In theory there could be a race here. In practice it is unlikely
1181 // and not worth worrying about.
1182 if (comp_level > mh->highest_comp_level()) {
1183 mh->set_highest_comp_level(comp_level);
1184 }
1185
1186 OrderAccess::storestore();
1187 #ifdef SHARK
1188 mh->_from_interpreted_entry = code->insts_begin();
1189 #else //!SHARK
1190 mh->_from_compiled_entry = code->verified_entry_point();
1191 OrderAccess::storestore();
1192 // Instantly compiled code can execute.
1193 if (!mh->is_method_handle_intrinsic())
1194 mh->_from_interpreted_entry = mh->get_i2c_entry();
1195 #endif //!SHARK
1196 }
1197
1198
1199 bool Method::is_overridden_in(Klass* k) const {
1200 InstanceKlass* ik = InstanceKlass::cast(k);
1201
1202 if (ik->is_interface()) return false;
1203
1204 // If method is an interface, we skip it - except if it
1205 // is a miranda method
1206 if (method_holder()->is_interface()) {
1207 // Check that method is not a miranda method
1208 if (ik->lookup_method(name(), signature()) == NULL) {
1209 // No implementation exist - so miranda method
1210 return false;
1211 }
1212 return true;
1213 }
1214
1215 assert(ik->is_subclass_of(method_holder()), "should be subklass");
1216 if (!has_vtable_index()) {
1217 return false;
1218 } else {
1219 Method* vt_m = ik->method_at_vtable(vtable_index());
1220 return vt_m != this;
1221 }
1222 }
1223
1224
1225 // give advice about whether this Method* should be cached or not
1226 bool Method::should_not_be_cached() const {
1227 if (is_old()) {
1228 // This method has been redefined. It is either EMCP or obsolete
1229 // and we don't want to cache it because that would pin the method
1230 // down and prevent it from being collectible if and when it
1231 // finishes executing.
1232 return true;
1233 }
1234
1235 // caching this method should be just fine
1236 return false;
1237 }
1238
1239
1240 /**
1241 * Returns true if this is one of the specially treated methods for
1242 * security related stack walks (like Reflection.getCallerClass).
1243 */
1244 bool Method::is_ignored_by_security_stack_walk() const {
1245 if (intrinsic_id() == vmIntrinsics::_invoke) {
1246 // This is Method.invoke() -- ignore it
1247 return true;
1248 }
1249 if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1250 // This is an auxilary frame -- ignore it
1251 return true;
1252 }
1253 if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1254 // This is an internal adapter frame for method handles -- ignore it
1255 return true;
1256 }
1257 return false;
1258 }
1259
1260
1261 // Constant pool structure for invoke methods:
1262 enum {
1263 _imcp_invoke_name = 1, // utf8: 'invokeExact', etc.
1264 _imcp_invoke_signature, // utf8: (variable Symbol*)
1265 _imcp_limit
1266 };
1267
1268 // Test if this method is an MH adapter frame generated by Java code.
1269 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1270 bool Method::is_compiled_lambda_form() const {
1271 return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1272 }
1273
1274 // Test if this method is an internal MH primitive method.
1275 bool Method::is_method_handle_intrinsic() const {
1276 vmIntrinsics::ID iid = intrinsic_id();
1277 return (MethodHandles::is_signature_polymorphic(iid) &&
1278 MethodHandles::is_signature_polymorphic_intrinsic(iid));
1279 }
1280
1281 bool Method::has_member_arg() const {
1282 vmIntrinsics::ID iid = intrinsic_id();
1283 return (MethodHandles::is_signature_polymorphic(iid) &&
1284 MethodHandles::has_member_arg(iid));
1285 }
1286
1287 // Make an instance of a signature-polymorphic internal MH primitive.
1288 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1289 Symbol* signature,
1290 TRAPS) {
1291 ResourceMark rm;
1292 methodHandle empty;
1293
1294 InstanceKlass* holder = SystemDictionary::MethodHandle_klass();
1295 Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1296 assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1297 if (TraceMethodHandles) {
1298 tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1299 }
1300
1301 // invariant: cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1302 name->increment_refcount();
1303 signature->increment_refcount();
1304
1305 int cp_length = _imcp_limit;
1306 ClassLoaderData* loader_data = holder->class_loader_data();
1307 constantPoolHandle cp;
1308 {
1309 ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1310 cp = constantPoolHandle(THREAD, cp_oop);
1311 }
1312 cp->set_pool_holder(holder);
1313 cp->symbol_at_put(_imcp_invoke_name, name);
1314 cp->symbol_at_put(_imcp_invoke_signature, signature);
1315 cp->set_has_preresolution();
1316
1317 // decide on access bits: public or not?
1318 int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1319 bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1320 if (must_be_static) flags_bits |= JVM_ACC_STATIC;
1321 assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1322
1323 methodHandle m;
1324 {
1325 InlineTableSizes sizes;
1326 Method* m_oop = Method::allocate(loader_data, 0,
1327 accessFlags_from(flags_bits), &sizes,
1328 ConstMethod::NORMAL, CHECK_(empty));
1329 m = methodHandle(THREAD, m_oop);
1330 }
1331 m->set_constants(cp());
1332 m->set_name_index(_imcp_invoke_name);
1333 m->set_signature_index(_imcp_invoke_signature);
1334 assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1335 assert(m->signature() == signature, "");
1336 ResultTypeFinder rtf(signature);
1337 m->constMethod()->set_result_type(rtf.type());
1338 m->compute_size_of_parameters(THREAD);
1339 m->init_intrinsic_id();
1340 assert(m->is_method_handle_intrinsic(), "");
1341 #ifdef ASSERT
1342 if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id())) m->print();
1343 assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1344 assert(m->intrinsic_id() == iid, "correctly predicted iid");
1345 #endif //ASSERT
1346
1347 // Finally, set up its entry points.
1348 assert(m->can_be_statically_bound(), "");
1349 m->set_vtable_index(Method::nonvirtual_vtable_index);
1350 m->link_method(m, CHECK_(empty));
1351
1352 if (TraceMethodHandles && (Verbose || WizardMode)) {
1353 ttyLocker ttyl;
1354 m->print_on(tty);
1355 }
1356
1357 return m;
1358 }
1359
1360 Klass* Method::check_non_bcp_klass(Klass* klass) {
1361 if (klass != NULL && klass->class_loader() != NULL) {
1362 if (klass->is_objArray_klass())
1363 klass = ObjArrayKlass::cast(klass)->bottom_klass();
1364 return klass;
1365 }
1366 return NULL;
1367 }
1368
1369
1370 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1371 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1372 // Code below does not work for native methods - they should never get rewritten anyway
1373 assert(!m->is_native(), "cannot rewrite native methods");
1374 // Allocate new Method*
1375 AccessFlags flags = m->access_flags();
1376
1377 ConstMethod* cm = m->constMethod();
1378 int checked_exceptions_len = cm->checked_exceptions_length();
1379 int localvariable_len = cm->localvariable_table_length();
1380 int exception_table_len = cm->exception_table_length();
1381 int method_parameters_len = cm->method_parameters_length();
1382 int method_annotations_len = cm->method_annotations_length();
1383 int parameter_annotations_len = cm->parameter_annotations_length();
1384 int type_annotations_len = cm->type_annotations_length();
1385 int default_annotations_len = cm->default_annotations_length();
1386
1387 InlineTableSizes sizes(
1388 localvariable_len,
1389 new_compressed_linenumber_size,
1390 exception_table_len,
1391 checked_exceptions_len,
1392 method_parameters_len,
1393 cm->generic_signature_index(),
1394 method_annotations_len,
1395 parameter_annotations_len,
1396 type_annotations_len,
1397 default_annotations_len,
1398 0);
1399
1400 ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1401 Method* newm_oop = Method::allocate(loader_data,
1402 new_code_length,
1403 flags,
1404 &sizes,
1405 m->method_type(),
1406 CHECK_(methodHandle()));
1407 methodHandle newm (THREAD, newm_oop);
1408
1409 // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1410 ConstMethod* newcm = newm->constMethod();
1411 int new_const_method_size = newm->constMethod()->size();
1412
1413 memcpy(newm(), m(), sizeof(Method));
1414
1415 // Create shallow copy of ConstMethod.
1416 memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1417
1418 // Reset correct method/const method, method size, and parameter info
1419 newm->set_constMethod(newcm);
1420 newm->constMethod()->set_code_size(new_code_length);
1421 newm->constMethod()->set_constMethod_size(new_const_method_size);
1422 assert(newm->code_size() == new_code_length, "check");
1423 assert(newm->method_parameters_length() == method_parameters_len, "check");
1424 assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1425 assert(newm->exception_table_length() == exception_table_len, "check");
1426 assert(newm->localvariable_table_length() == localvariable_len, "check");
1427 // Copy new byte codes
1428 memcpy(newm->code_base(), new_code, new_code_length);
1429 // Copy line number table
1430 if (new_compressed_linenumber_size > 0) {
1431 memcpy(newm->compressed_linenumber_table(),
1432 new_compressed_linenumber_table,
1433 new_compressed_linenumber_size);
1434 }
1435 // Copy method_parameters
1436 if (method_parameters_len > 0) {
1437 memcpy(newm->method_parameters_start(),
1438 m->method_parameters_start(),
1439 method_parameters_len * sizeof(MethodParametersElement));
1440 }
1441 // Copy checked_exceptions
1442 if (checked_exceptions_len > 0) {
1443 memcpy(newm->checked_exceptions_start(),
1444 m->checked_exceptions_start(),
1445 checked_exceptions_len * sizeof(CheckedExceptionElement));
1446 }
1447 // Copy exception table
1448 if (exception_table_len > 0) {
1449 memcpy(newm->exception_table_start(),
1450 m->exception_table_start(),
1451 exception_table_len * sizeof(ExceptionTableElement));
1452 }
1453 // Copy local variable number table
1454 if (localvariable_len > 0) {
1455 memcpy(newm->localvariable_table_start(),
1456 m->localvariable_table_start(),
1457 localvariable_len * sizeof(LocalVariableTableElement));
1458 }
1459 // Copy stackmap table
1460 if (m->has_stackmap_table()) {
1461 int code_attribute_length = m->stackmap_data()->length();
1462 Array<u1>* stackmap_data =
1463 MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1464 memcpy((void*)stackmap_data->adr_at(0),
1465 (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1466 newm->set_stackmap_data(stackmap_data);
1467 }
1468
1469 // copy annotations over to new method
1470 newcm->copy_annotations_from(loader_data, cm, CHECK_NULL);
1471 return newm;
1472 }
1473
1474 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1475 // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1476 // because we are not loading from core libraries
1477 // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1478 // which does not use the class default class loader so we check for its loader here
1479 const InstanceKlass* ik = InstanceKlass::cast(holder);
1480 if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1481 return vmSymbols::NO_SID; // regardless of name, no intrinsics here
1482 }
1483
1484 // see if the klass name is well-known:
1485 Symbol* klass_name = ik->name();
1486 return vmSymbols::find_sid(klass_name);
1487 }
1488
1489 void Method::init_intrinsic_id() {
1490 assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1491 const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1492 assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1493 assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1494
1495 // the klass name is well-known:
1496 vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1497 assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1498
1499 // ditto for method and signature:
1500 vmSymbols::SID name_id = vmSymbols::find_sid(name());
1501 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1502 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1503 && name_id == vmSymbols::NO_SID) {
1504 return;
1505 }
1506 vmSymbols::SID sig_id = vmSymbols::find_sid(signature());
1507 if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1508 && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1509 && sig_id == vmSymbols::NO_SID) {
1510 return;
1511 }
1512 jshort flags = access_flags().as_short();
1513
1514 vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1515 if (id != vmIntrinsics::_none) {
1516 set_intrinsic_id(id);
1517 if (id == vmIntrinsics::_Class_cast) {
1518 // Even if the intrinsic is rejected, we want to inline this simple method.
1519 set_force_inline(true);
1520 }
1521 return;
1522 }
1523
1524 // A few slightly irregular cases:
1525 switch (klass_id) {
1526 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1527 // Second chance: check in regular Math.
1528 switch (name_id) {
1529 case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1530 case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1531 case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1532 // pretend it is the corresponding method in the non-strict class:
1533 klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1534 id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1535 break;
1536 }
1537 break;
1538
1539 // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1540 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1541 case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1542 if (!is_native()) break;
1543 id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1544 if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1545 id = vmIntrinsics::_none;
1546 break;
1547 }
1548
1549 if (id != vmIntrinsics::_none) {
1550 // Set up its iid. It is an alias method.
1551 set_intrinsic_id(id);
1552 return;
1553 }
1554 }
1555
1556 // These two methods are static since a GC may move the Method
1557 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1558 if (!THREAD->can_call_java()) {
1559 // There is nothing useful this routine can do from within the Compile thread.
1560 // Hopefully, the signature contains only well-known classes.
1561 // We could scan for this and return true/false, but the caller won't care.
1562 return false;
1563 }
1564 bool sig_is_loaded = true;
1565 Handle class_loader(THREAD, m->method_holder()->class_loader());
1566 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1567 ResourceMark rm(THREAD);
1568 Symbol* signature = m->signature();
1569 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1570 if (ss.is_object()) {
1571 Symbol* sym = ss.as_symbol(CHECK_(false));
1572 Symbol* name = sym;
1573 Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1574 protection_domain, THREAD);
1575 // We are loading classes eagerly. If a ClassNotFoundException or
1576 // a LinkageError was generated, be sure to ignore it.
1577 if (HAS_PENDING_EXCEPTION) {
1578 if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1579 PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1580 CLEAR_PENDING_EXCEPTION;
1581 } else {
1582 return false;
1583 }
1584 }
1585 if( klass == NULL) { sig_is_loaded = false; }
1586 }
1587 }
1588 return sig_is_loaded;
1589 }
1590
1591 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1592 Handle class_loader(THREAD, m->method_holder()->class_loader());
1593 Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1594 ResourceMark rm(THREAD);
1595 Symbol* signature = m->signature();
1596 for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1597 if (ss.type() == T_OBJECT) {
1598 Symbol* name = ss.as_symbol_or_null();
1599 if (name == NULL) return true;
1600 Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1601 if (klass == NULL) return true;
1602 }
1603 }
1604 return false;
1605 }
1606
1607 // Exposed so field engineers can debug VM
1608 void Method::print_short_name(outputStream* st) {
1609 ResourceMark rm;
1610 #ifdef PRODUCT
1611 st->print(" %s::", method_holder()->external_name());
1612 #else
1613 st->print(" %s::", method_holder()->internal_name());
1614 #endif
1615 name()->print_symbol_on(st);
1616 if (WizardMode) signature()->print_symbol_on(st);
1617 else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1618 MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1619 }
1620
1621 // Comparer for sorting an object array containing
1622 // Method*s.
1623 static int method_comparator(Method* a, Method* b) {
1624 return a->name()->fast_compare(b->name());
1625 }
1626
1627 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1628 // default_methods also uses this without the ordering for fast find_method
1629 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1630 int length = methods->length();
1631 if (length > 1) {
1632 {
1633 NoSafepointVerifier nsv;
1634 QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1635 }
1636 // Reset method ordering
1637 if (set_idnums) {
1638 for (int i = 0; i < length; i++) {
1639 Method* m = methods->at(i);
1640 m->set_method_idnum(i);
1641 m->set_orig_method_idnum(i);
1642 }
1643 }
1644 }
1645 }
1646
1647 //-----------------------------------------------------------------------------------
1648 // Non-product code unless JVM/TI needs it
1649
1650 #if !defined(PRODUCT) || INCLUDE_JVMTI
1651 class SignatureTypePrinter : public SignatureTypeNames {
1652 private:
1653 outputStream* _st;
1654 bool _use_separator;
1655
1656 void type_name(const char* name) {
1657 if (_use_separator) _st->print(", ");
1658 _st->print("%s", name);
1659 _use_separator = true;
1660 }
1661
1662 public:
1663 SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1664 _st = st;
1665 _use_separator = false;
1666 }
1667
1668 void print_parameters() { _use_separator = false; iterate_parameters(); }
1669 void print_returntype() { _use_separator = false; iterate_returntype(); }
1670 };
1671
1672
1673 void Method::print_name(outputStream* st) {
1674 Thread *thread = Thread::current();
1675 ResourceMark rm(thread);
1676 st->print("%s ", is_static() ? "static" : "virtual");
1677 if (WizardMode) {
1678 st->print("%s.", method_holder()->internal_name());
1679 name()->print_symbol_on(st);
1680 signature()->print_symbol_on(st);
1681 } else {
1682 SignatureTypePrinter sig(signature(), st);
1683 sig.print_returntype();
1684 st->print(" %s.", method_holder()->internal_name());
1685 name()->print_symbol_on(st);
1686 st->print("(");
1687 sig.print_parameters();
1688 st->print(")");
1689 }
1690 }
1691 #endif // !PRODUCT || INCLUDE_JVMTI
1692
1693
1694 void Method::print_codes_on(outputStream* st) const {
1695 print_codes_on(0, code_size(), st);
1696 }
1697
1698 void Method::print_codes_on(int from, int to, outputStream* st) const {
1699 Thread *thread = Thread::current();
1700 ResourceMark rm(thread);
1701 methodHandle mh (thread, (Method*)this);
1702 BytecodeStream s(mh);
1703 s.set_interval(from, to);
1704 BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1705 while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1706 }
1707
1708
1709 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1710 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1711 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1712 // as end-of-stream terminator.
1713
1714 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1715 // bci and line number does not compress into single byte.
1716 // Write out escape character and use regular compression for bci and line number.
1717 write_byte((jubyte)0xFF);
1718 write_signed_int(bci_delta);
1719 write_signed_int(line_delta);
1720 }
1721
1722 // See comment in method.hpp which explains why this exists.
1723 #if defined(_M_AMD64) && _MSC_VER >= 1400
1724 #pragma optimize("", off)
1725 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1726 write_pair_inline(bci, line);
1727 }
1728 #pragma optimize("", on)
1729 #endif
1730
1731 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1732 _bci = 0;
1733 _line = 0;
1734 };
1735
1736
1737 bool CompressedLineNumberReadStream::read_pair() {
1738 jubyte next = read_byte();
1739 // Check for terminator
1740 if (next == 0) return false;
1741 if (next == 0xFF) {
1742 // Escape character, regular compression used
1743 _bci += read_signed_int();
1744 _line += read_signed_int();
1745 } else {
1746 // Single byte compression used
1747 _bci += next >> 3;
1748 _line += next & 0x7;
1749 }
1750 return true;
1751 }
1752
1753 #if INCLUDE_JVMTI
1754
1755 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1756 BreakpointInfo* bp = method_holder()->breakpoints();
1757 for (; bp != NULL; bp = bp->next()) {
1758 if (bp->match(this, bci)) {
1759 return bp->orig_bytecode();
1760 }
1761 }
1762 {
1763 ResourceMark rm;
1764 fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1765 }
1766 return Bytecodes::_shouldnotreachhere;
1767 }
1768
1769 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1770 assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1771 BreakpointInfo* bp = method_holder()->breakpoints();
1772 for (; bp != NULL; bp = bp->next()) {
1773 if (bp->match(this, bci)) {
1774 bp->set_orig_bytecode(code);
1775 // and continue, in case there is more than one
1776 }
1777 }
1778 }
1779
1780 void Method::set_breakpoint(int bci) {
1781 InstanceKlass* ik = method_holder();
1782 BreakpointInfo *bp = new BreakpointInfo(this, bci);
1783 bp->set_next(ik->breakpoints());
1784 ik->set_breakpoints(bp);
1785 // do this last:
1786 bp->set(this);
1787 }
1788
1789 static void clear_matches(Method* m, int bci) {
1790 InstanceKlass* ik = m->method_holder();
1791 BreakpointInfo* prev_bp = NULL;
1792 BreakpointInfo* next_bp;
1793 for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1794 next_bp = bp->next();
1795 // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1796 if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1797 // do this first:
1798 bp->clear(m);
1799 // unhook it
1800 if (prev_bp != NULL)
1801 prev_bp->set_next(next_bp);
1802 else
1803 ik->set_breakpoints(next_bp);
1804 delete bp;
1805 // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1806 // at same location. So we have multiple matching (method_index and bci)
1807 // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1808 // breakpoint for clear_breakpoint request and keep all other method versions
1809 // BreakpointInfo for future clear_breakpoint request.
1810 // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1811 // which is being called when class is unloaded. We delete all the Breakpoint
1812 // information for all versions of method. We may not correctly restore the original
1813 // bytecode in all method versions, but that is ok. Because the class is being unloaded
1814 // so these methods won't be used anymore.
1815 if (bci >= 0) {
1816 break;
1817 }
1818 } else {
1819 // This one is a keeper.
1820 prev_bp = bp;
1821 }
1822 }
1823 }
1824
1825 void Method::clear_breakpoint(int bci) {
1826 assert(bci >= 0, "");
1827 clear_matches(this, bci);
1828 }
1829
1830 void Method::clear_all_breakpoints() {
1831 clear_matches(this, -1);
1832 }
1833
1834 #endif // INCLUDE_JVMTI
1835
1836 int Method::invocation_count() {
1837 MethodCounters *mcs = method_counters();
1838 if (TieredCompilation) {
1839 MethodData* const mdo = method_data();
1840 if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1841 ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1842 return InvocationCounter::count_limit;
1843 } else {
1844 return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1845 ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1846 }
1847 } else {
1848 return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1849 }
1850 }
1851
1852 int Method::backedge_count() {
1853 MethodCounters *mcs = method_counters();
1854 if (TieredCompilation) {
1855 MethodData* const mdo = method_data();
1856 if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1857 ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1858 return InvocationCounter::count_limit;
1859 } else {
1860 return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1861 ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1862 }
1863 } else {
1864 return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1865 }
1866 }
1867
1868 int Method::highest_comp_level() const {
1869 const MethodCounters* mcs = method_counters();
1870 if (mcs != NULL) {
1871 return mcs->highest_comp_level();
1872 } else {
1873 return CompLevel_none;
1874 }
1875 }
1876
1877 int Method::highest_osr_comp_level() const {
1878 const MethodCounters* mcs = method_counters();
1879 if (mcs != NULL) {
1880 return mcs->highest_osr_comp_level();
1881 } else {
1882 return CompLevel_none;
1883 }
1884 }
1885
1886 void Method::set_highest_comp_level(int level) {
1887 MethodCounters* mcs = method_counters();
1888 if (mcs != NULL) {
1889 mcs->set_highest_comp_level(level);
1890 }
1891 }
1892
1893 void Method::set_highest_osr_comp_level(int level) {
1894 MethodCounters* mcs = method_counters();
1895 if (mcs != NULL) {
1896 mcs->set_highest_osr_comp_level(level);
1897 }
1898 }
1899
1900 #if INCLUDE_JVMTI
1901
1902 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1903 _bci = bci;
1904 _name_index = m->name_index();
1905 _signature_index = m->signature_index();
1906 _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1907 if (_orig_bytecode == Bytecodes::_breakpoint)
1908 _orig_bytecode = m->orig_bytecode_at(_bci);
1909 _next = NULL;
1910 }
1911
1912 void BreakpointInfo::set(Method* method) {
1913 #ifdef ASSERT
1914 {
1915 Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1916 if (code == Bytecodes::_breakpoint)
1917 code = method->orig_bytecode_at(_bci);
1918 assert(orig_bytecode() == code, "original bytecode must be the same");
1919 }
1920 #endif
1921 Thread *thread = Thread::current();
1922 *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1923 method->incr_number_of_breakpoints(thread);
1924 SystemDictionary::notice_modification();
1925 {
1926 // Deoptimize all dependents on this method
1927 HandleMark hm(thread);
1928 methodHandle mh(thread, method);
1929 CodeCache::flush_dependents_on_method(mh);
1930 }
1931 }
1932
1933 void BreakpointInfo::clear(Method* method) {
1934 *method->bcp_from(_bci) = orig_bytecode();
1935 assert(method->number_of_breakpoints() > 0, "must not go negative");
1936 method->decr_number_of_breakpoints(Thread::current());
1937 }
1938
1939 #endif // INCLUDE_JVMTI
1940
1941 // jmethodID handling
1942
1943 // This is a block allocating object, sort of like JNIHandleBlock, only a
1944 // lot simpler.
1945 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1946 // never get rid of it.
1947
1948 static const int min_block_size = 8;
1949
1950 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1951 friend class JNIMethodBlock;
1952 Method** _methods;
1953 int _number_of_methods;
1954 int _top;
1955 JNIMethodBlockNode* _next;
1956
1957 public:
1958
1959 JNIMethodBlockNode(int num_methods = min_block_size);
1960
1961 ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1962
1963 void ensure_methods(int num_addl_methods) {
1964 if (_top < _number_of_methods) {
1965 num_addl_methods -= _number_of_methods - _top;
1966 if (num_addl_methods <= 0) {
1967 return;
1968 }
1969 }
1970 if (_next == NULL) {
1971 _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1972 } else {
1973 _next->ensure_methods(num_addl_methods);
1974 }
1975 }
1976 };
1977
1978 class JNIMethodBlock : public CHeapObj<mtClass> {
1979 JNIMethodBlockNode _head;
1980 JNIMethodBlockNode *_last_free;
1981 public:
1982 static Method* const _free_method;
1983
1984 JNIMethodBlock(int initial_capacity = min_block_size)
1985 : _head(initial_capacity), _last_free(&_head) {}
1986
1987 void ensure_methods(int num_addl_methods) {
1988 _last_free->ensure_methods(num_addl_methods);
1989 }
1990
1991 Method** add_method(Method* m) {
1992 for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1993 if (b->_top < b->_number_of_methods) {
1994 // top points to the next free entry.
1995 int i = b->_top;
1996 b->_methods[i] = m;
1997 b->_top++;
1998 _last_free = b;
1999 return &(b->_methods[i]);
2000 } else if (b->_top == b->_number_of_methods) {
2001 // if the next free entry ran off the block see if there's a free entry
2002 for (int i = 0; i < b->_number_of_methods; i++) {
2003 if (b->_methods[i] == _free_method) {
2004 b->_methods[i] = m;
2005 _last_free = b;
2006 return &(b->_methods[i]);
2007 }
2008 }
2009 // Only check each block once for frees. They're very unlikely.
2010 // Increment top past the end of the block.
2011 b->_top++;
2012 }
2013 // need to allocate a next block.
2014 if (b->_next == NULL) {
2015 b->_next = _last_free = new JNIMethodBlockNode();
2016 }
2017 }
2018 guarantee(false, "Should always allocate a free block");
2019 return NULL;
2020 }
2021
2022 bool contains(Method** m) {
2023 if (m == NULL) return false;
2024 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2025 if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
2026 // This is a bit of extra checking, for two reasons. One is
2027 // that contains() deals with pointers that are passed in by
2028 // JNI code, so making sure that the pointer is aligned
2029 // correctly is valuable. The other is that <= and > are
2030 // technically not defined on pointers, so the if guard can
2031 // pass spuriously; no modern compiler is likely to make that
2032 // a problem, though (and if one did, the guard could also
2033 // fail spuriously, which would be bad).
2034 ptrdiff_t idx = m - b->_methods;
2035 if (b->_methods + idx == m) {
2036 return true;
2037 }
2038 }
2039 }
2040 return false; // not found
2041 }
2042
2043 // Doesn't really destroy it, just marks it as free so it can be reused.
2044 void destroy_method(Method** m) {
2045 #ifdef ASSERT
2046 assert(contains(m), "should be a methodID");
2047 #endif // ASSERT
2048 *m = _free_method;
2049 }
2050
2051 // During class unloading the methods are cleared, which is different
2052 // than freed.
2053 void clear_all_methods() {
2054 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2055 for (int i = 0; i< b->_number_of_methods; i++) {
2056 b->_methods[i] = NULL;
2057 }
2058 }
2059 }
2060 #ifndef PRODUCT
2061 int count_methods() {
2062 // count all allocated methods
2063 int count = 0;
2064 for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
2065 for (int i = 0; i< b->_number_of_methods; i++) {
2066 if (b->_methods[i] != _free_method) count++;
2067 }
2068 }
2069 return count;
2070 }
2071 #endif // PRODUCT
2072 };
2073
2074 // Something that can't be mistaken for an address or a markOop
2075 Method* const JNIMethodBlock::_free_method = (Method*)55;
2076
2077 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
2078 _number_of_methods = MAX2(num_methods, min_block_size);
2079 _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
2080 for (int i = 0; i < _number_of_methods; i++) {
2081 _methods[i] = JNIMethodBlock::_free_method;
2082 }
2083 }
2084
2085 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
2086 ClassLoaderData* cld = loader_data;
2087 if (!SafepointSynchronize::is_at_safepoint()) {
2088 // Have to add jmethod_ids() to class loader data thread-safely.
2089 // Also have to add the method to the list safely, which the cld lock
2090 // protects as well.
2091 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2092 if (cld->jmethod_ids() == NULL) {
2093 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2094 } else {
2095 cld->jmethod_ids()->ensure_methods(capacity);
2096 }
2097 } else {
2098 // At safepoint, we are single threaded and can set this.
2099 if (cld->jmethod_ids() == NULL) {
2100 cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2101 } else {
2102 cld->jmethod_ids()->ensure_methods(capacity);
2103 }
2104 }
2105 }
2106
2107 // Add a method id to the jmethod_ids
2108 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2109 ClassLoaderData* cld = loader_data;
2110
2111 if (!SafepointSynchronize::is_at_safepoint()) {
2112 // Have to add jmethod_ids() to class loader data thread-safely.
2113 // Also have to add the method to the list safely, which the cld lock
2114 // protects as well.
2115 MutexLockerEx ml(cld->metaspace_lock(), Mutex::_no_safepoint_check_flag);
2116 if (cld->jmethod_ids() == NULL) {
2117 cld->set_jmethod_ids(new JNIMethodBlock());
2118 }
2119 // jmethodID is a pointer to Method*
2120 return (jmethodID)cld->jmethod_ids()->add_method(m);
2121 } else {
2122 // At safepoint, we are single threaded and can set this.
2123 if (cld->jmethod_ids() == NULL) {
2124 cld->set_jmethod_ids(new JNIMethodBlock());
2125 }
2126 // jmethodID is a pointer to Method*
2127 return (jmethodID)cld->jmethod_ids()->add_method(m);
2128 }
2129 }
2130
2131 // Mark a jmethodID as free. This is called when there is a data race in
2132 // InstanceKlass while creating the jmethodID cache.
2133 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2134 ClassLoaderData* cld = loader_data;
2135 Method** ptr = (Method**)m;
2136 assert(cld->jmethod_ids() != NULL, "should have method handles");
2137 cld->jmethod_ids()->destroy_method(ptr);
2138 }
2139
2140 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2141 // Can't assert the method_holder is the same because the new method has the
2142 // scratch method holder.
2143 assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2144 == new_method->method_holder()->class_loader(),
2145 "changing to a different class loader");
2146 // Just change the method in place, jmethodID pointer doesn't change.
2147 *((Method**)jmid) = new_method;
2148 }
2149
2150 bool Method::is_method_id(jmethodID mid) {
2151 Method* m = resolve_jmethod_id(mid);
2152 assert(m != NULL, "should be called with non-null method");
2153 InstanceKlass* ik = m->method_holder();
2154 ClassLoaderData* cld = ik->class_loader_data();
2155 if (cld->jmethod_ids() == NULL) return false;
2156 return (cld->jmethod_ids()->contains((Method**)mid));
2157 }
2158
2159 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2160 if (mid == NULL) return NULL;
2161 Method* o = resolve_jmethod_id(mid);
2162 if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2163 return NULL;
2164 }
2165 return o;
2166 };
2167
2168 void Method::set_on_stack(const bool value) {
2169 // Set both the method itself and its constant pool. The constant pool
2170 // on stack means some method referring to it is also on the stack.
2171 constants()->set_on_stack(value);
2172
2173 bool already_set = on_stack();
2174 _access_flags.set_on_stack(value);
2175 if (value && !already_set) {
2176 MetadataOnStackMark::record(this);
2177 }
2178 }
2179
2180 // Called when the class loader is unloaded to make all methods weak.
2181 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2182 loader_data->jmethod_ids()->clear_all_methods();
2183 }
2184
2185 bool Method::has_method_vptr(const void* ptr) {
2186 Method m;
2187 // This assumes that the vtbl pointer is the first word of a C++ object.
2188 return dereference_vptr(&m) == dereference_vptr(ptr);
2189 }
2190
2191 // Check that this pointer is valid by checking that the vtbl pointer matches
2192 bool Method::is_valid_method() const {
2193 if (this == NULL) {
2194 return false;
2195 } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2196 // Quick sanity check on pointer.
2197 return false;
2198 } else if (MetaspaceShared::is_in_shared_space(this)) {
2199 return MetaspaceShared::is_valid_shared_method(this);
2200 } else if (Metaspace::contains_non_shared(this)) {
2201 return has_method_vptr((const void*)this);
2202 } else {
2203 return false;
2204 }
2205 }
2206
2207 #ifndef PRODUCT
2208 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
2209 out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2210 }
2211 #endif // PRODUCT
2212
2213
2214 // Printing
2215
2216 #ifndef PRODUCT
2217
2218 void Method::print_on(outputStream* st) const {
2219 ResourceMark rm;
2220 assert(is_method(), "must be method");
2221 st->print_cr("%s", internal_name());
2222 st->print_cr(" - this oop: " INTPTR_FORMAT, p2i(this));
2223 st->print (" - method holder: "); method_holder()->print_value_on(st); st->cr();
2224 st->print (" - constants: " INTPTR_FORMAT " ", p2i(constants()));
2225 constants()->print_value_on(st); st->cr();
2226 st->print (" - access: 0x%x ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2227 st->print (" - name: "); name()->print_value_on(st); st->cr();
2228 st->print (" - signature: "); signature()->print_value_on(st); st->cr();
2229 st->print_cr(" - max stack: %d", max_stack());
2230 st->print_cr(" - max locals: %d", max_locals());
2231 st->print_cr(" - size of params: %d", size_of_parameters());
2232 st->print_cr(" - method size: %d", method_size());
2233 if (intrinsic_id() != vmIntrinsics::_none)
2234 st->print_cr(" - intrinsic id: %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2235 if (highest_comp_level() != CompLevel_none)
2236 st->print_cr(" - highest level: %d", highest_comp_level());
2237 st->print_cr(" - vtable index: %d", _vtable_index);
2238 if (valid_itable_index())
2239 st->print_cr(" - itable index: %d", itable_index());
2240 st->print_cr(" - i2i entry: " INTPTR_FORMAT, p2i(interpreter_entry()));
2241 st->print( " - adapters: ");
2242 AdapterHandlerEntry* a = ((Method*)this)->adapter();
2243 if (a == NULL)
2244 st->print_cr(INTPTR_FORMAT, p2i(a));
2245 else
2246 a->print_adapter_on(st);
2247 st->print_cr(" - compiled entry " INTPTR_FORMAT, p2i(from_compiled_entry()));
2248 st->print_cr(" - code size: %d", code_size());
2249 if (code_size() != 0) {
2250 st->print_cr(" - code start: " INTPTR_FORMAT, p2i(code_base()));
2251 st->print_cr(" - code end (excl): " INTPTR_FORMAT, p2i(code_base() + code_size()));
2252 }
2253 if (method_data() != NULL) {
2254 st->print_cr(" - method data: " INTPTR_FORMAT, p2i(method_data()));
2255 }
2256 st->print_cr(" - checked ex length: %d", checked_exceptions_length());
2257 if (checked_exceptions_length() > 0) {
2258 CheckedExceptionElement* table = checked_exceptions_start();
2259 st->print_cr(" - checked ex start: " INTPTR_FORMAT, p2i(table));
2260 if (Verbose) {
2261 for (int i = 0; i < checked_exceptions_length(); i++) {
2262 st->print_cr(" - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2263 }
2264 }
2265 }
2266 if (has_linenumber_table()) {
2267 u_char* table = compressed_linenumber_table();
2268 st->print_cr(" - linenumber start: " INTPTR_FORMAT, p2i(table));
2269 if (Verbose) {
2270 CompressedLineNumberReadStream stream(table);
2271 while (stream.read_pair()) {
2272 st->print_cr(" - line %d: %d", stream.line(), stream.bci());
2273 }
2274 }
2275 }
2276 st->print_cr(" - localvar length: %d", localvariable_table_length());
2277 if (localvariable_table_length() > 0) {
2278 LocalVariableTableElement* table = localvariable_table_start();
2279 st->print_cr(" - localvar start: " INTPTR_FORMAT, p2i(table));
2280 if (Verbose) {
2281 for (int i = 0; i < localvariable_table_length(); i++) {
2282 int bci = table[i].start_bci;
2283 int len = table[i].length;
2284 const char* name = constants()->printable_name_at(table[i].name_cp_index);
2285 const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2286 int slot = table[i].slot;
2287 st->print_cr(" - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2288 }
2289 }
2290 }
2291 if (code() != NULL) {
2292 st->print (" - compiled code: ");
2293 code()->print_value_on(st);
2294 }
2295 if (is_native()) {
2296 st->print_cr(" - native function: " INTPTR_FORMAT, p2i(native_function()));
2297 st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2298 }
2299 }
2300
2301 void Method::print_linkage_flags(outputStream* st) {
2302 access_flags().print_on(st);
2303 if (is_default_method()) {
2304 st->print("default ");
2305 }
2306 if (is_overpass()) {
2307 st->print("overpass ");
2308 }
2309 }
2310 #endif //PRODUCT
2311
2312 void Method::print_value_on(outputStream* st) const {
2313 assert(is_method(), "must be method");
2314 st->print("%s", internal_name());
2315 print_address_on(st);
2316 st->print(" ");
2317 if (WizardMode) access_flags().print_on(st);
2318 name()->print_value_on(st);
2319 st->print(" ");
2320 signature()->print_value_on(st);
2321 st->print(" in ");
2322 method_holder()->print_value_on(st);
2323 if (WizardMode) st->print("#%d", _vtable_index);
2324 if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2325 if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2326 }
2327
2328 #if INCLUDE_SERVICES
2329 // Size Statistics
2330 void Method::collect_statistics(KlassSizeStats *sz) const {
2331 int mysize = sz->count(this);
2332 sz->_method_bytes += mysize;
2333 sz->_method_all_bytes += mysize;
2334 sz->_rw_bytes += mysize;
2335
2336 if (constMethod()) {
2337 constMethod()->collect_statistics(sz);
2338 }
2339 if (method_data()) {
2340 method_data()->collect_statistics(sz);
2341 }
2342 }
2343 #endif // INCLUDE_SERVICES
2344
2345 // LogTouchedMethods and PrintTouchedMethods
2346
2347 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2348 // the Method may be garbage collected. Let's roll our own hash table.
2349 class TouchedMethodRecord : CHeapObj<mtTracing> {
2350 public:
2351 // It's OK to store Symbols here because they will NOT be GC'ed if
2352 // LogTouchedMethods is enabled.
2353 TouchedMethodRecord* _next;
2354 Symbol* _class_name;
2355 Symbol* _method_name;
2356 Symbol* _method_signature;
2357 };
2358
2359 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2360 static TouchedMethodRecord** _touched_method_table = NULL;
2361
2362 void Method::log_touched(TRAPS) {
2363
2364 const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2365 Symbol* my_class = klass_name();
2366 Symbol* my_name = name();
2367 Symbol* my_sig = signature();
2368
2369 unsigned int hash = my_class->identity_hash() +
2370 my_name->identity_hash() +
2371 my_sig->identity_hash();
2372 juint index = juint(hash) % table_size;
2373
2374 MutexLocker ml(TouchedMethodLog_lock, THREAD);
2375 if (_touched_method_table == NULL) {
2376 _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2377 mtTracing, CURRENT_PC);
2378 memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2379 }
2380
2381 TouchedMethodRecord* ptr = _touched_method_table[index];
2382 while (ptr) {
2383 if (ptr->_class_name == my_class &&
2384 ptr->_method_name == my_name &&
2385 ptr->_method_signature == my_sig) {
2386 return;
2387 }
2388 if (ptr->_next == NULL) break;
2389 ptr = ptr->_next;
2390 }
2391 TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2392 my_class->set_permanent(); // prevent reclaimed by GC
2393 my_name->set_permanent();
2394 my_sig->set_permanent();
2395 nptr->_class_name = my_class;
2396 nptr->_method_name = my_name;
2397 nptr->_method_signature = my_sig;
2398 nptr->_next = NULL;
2399
2400 if (ptr == NULL) {
2401 // first
2402 _touched_method_table[index] = nptr;
2403 } else {
2404 ptr->_next = nptr;
2405 }
2406 }
2407
2408 void Method::print_touched_methods(outputStream* out) {
2409 MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2410 out->print_cr("# Method::print_touched_methods version 1");
2411 if (_touched_method_table) {
2412 for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2413 TouchedMethodRecord* ptr = _touched_method_table[i];
2414 while(ptr) {
2415 ptr->_class_name->print_symbol_on(out); out->print(".");
2416 ptr->_method_name->print_symbol_on(out); out->print(":");
2417 ptr->_method_signature->print_symbol_on(out); out->cr();
2418 ptr = ptr->_next;
2419 }
2420 }
2421 }
2422 }
2423
2424 // Verification
2425
2426 void Method::verify_on(outputStream* st) {
2427 guarantee(is_method(), "object must be method");
2428 guarantee(constants()->is_constantPool(), "should be constant pool");
2429 guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2430 MethodData* md = method_data();
2431 guarantee(md == NULL ||
2432 md->is_methodData(), "should be method data");
2433 }